Editor's Choice Articles

Editor’s Choice articles are based on recommendations by the scientific editors of MDPI journals from around the world. Editors select a small number of articles recently published in the journal that they believe will be particularly interesting to authors, or important in this field. The aim is to provide a snapshot of some of the most exciting work published in the various research areas of the journal.

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Article
Multi-Omics Data Analysis of Gene Expressions and Alterations, Cancer-Associated Fibroblast and Immune Infiltrations, Reveals the Onco-Immune Prognostic Relevance of STAT3/CDK2/4/6 in Human Malignancies
Cancers 2021, 13(5), 954; https://doi.org/10.3390/cancers13050954 - 25 Feb 2021
Cited by 18
Abstract
Signal transducer and activator of transcription 3 (STAT3)/Cyclin-dependent kinases are multifunctional proteins that play an important implicative role in cancer initiations, progression, drug resistance, and metastasis, and has been extensively explored in cancer therapy. However, the genetic alterations of STAT3/CDK2/4/6 and its role [...] Read more.
Signal transducer and activator of transcription 3 (STAT3)/Cyclin-dependent kinases are multifunctional proteins that play an important implicative role in cancer initiations, progression, drug resistance, and metastasis, and has been extensively explored in cancer therapy. However, the genetic alterations of STAT3/CDK2/4/6 and its role in predicting immune infiltration and immunotherapeutic response are yet to be well exploited. In this study, we use in silico methods to analyze differential expression, prognostic value, genetic and epigenetic alterations, association with tumor-infiltrating immune cells, and cancer-associated fibroblast (CAF) infiltrations of STAT3/CDK2/4/6 in multiple cancer types. Our results revealed that the expression of STAT3/CDK2/4/6 was altered in various cancers and is associated with poor overall and disease-free survival of the cohorts. Moreover, genetic alterations in STAT3/CDK2/4/6 co-occurred with a number of other genetic alterations and are associated with poorer prognoses of the cohorts. The protein-protein interaction (PPI) network analysis suggests CDK2/4/6/STAT3 may directly interact with factors that promote tumorigenesis and immune response. We found that STAT3/CDK2/4/6 expressions were associated with infiltrations of CAF and the various immune cells in multiple cancers and it’s associated with poor response to immunotherapy. Collectively, our study suggested that STAT3/CDK2/4/6 are important onco-immune signatures that play central roles in tumor immune invasion, poor prognoses and, immune therapy response. Findings from the present study may therefore be clinically useful in prognosis assessment and follow-up management of immunotherapy. Full article
(This article belongs to the Collection The Biomarkers for the Diagnosis and Prognosis in Cancer)
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Article
Prognostic Significance of Gene Expression and DNA Methylation Markers in Circulating Tumor Cells and Paired Plasma Derived Exosomes in Metastatic Castration Resistant Prostate Cancer
Cancers 2021, 13(4), 780; https://doi.org/10.3390/cancers13040780 - 13 Feb 2021
Cited by 25
Abstract
Liquid biopsy, based on the analysis of circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA), provides non-invasive real-time monitoring of tumor evolution and therapeutic efficacy. We performed for the first time a direct comparison study on gene expression and DNA methylation markers [...] Read more.
Liquid biopsy, based on the analysis of circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA), provides non-invasive real-time monitoring of tumor evolution and therapeutic efficacy. We performed for the first time a direct comparison study on gene expression and DNA methylation markers in CTCs and paired plasma-derived exosomes and evaluated their prognostic significance in metastatic castration resistant prostate cancer. This prospective liquid biopsy (LB) study was based on a group of 62 metastatic castration resistant prostate cancer (mCRPC) patients and 10 healthy donors (HD) as controls. Identical blood draws were used to: (a) enumerate CTC and tumor-derived extracellular vesicles (tdEVs) using CellSearch (CS) and (b) analyze CTCs and paired plasma-derived exosomes at the gene expression and DNA methylation level. CTCs were enumerated using CellSearch in 57/62 patients, with values ranging from 5 to 854 cells/7.5 mL PB. Our results revealed for the first time a significantly higher positivity of gene expression markers (CK-8, CK-18, TWIST1, PSMA, AR-FL, AR-V7, AR-567 and PD-L1 mRNA) in EpCAM-positive CTCs compared to plasma-derived exosomes. GSTP1, RASSF1A and SCHLAFEN were methylated both in CTC and exosomes. In CTCs, Kaplan–Meier analysis revealed that CK-19 (p = 0.009), PSMA (p = 0.001), TWIST1 (p = 0.001) expression and GSTP1 (p = 0.001) methylation were correlated with OS, while in exosomes GSTP1 (p = 0.007) and RASSF1A (p = 0.001) methylation was correlated with OS. Our direct comparison study of CTCs and exosomes at gene expression and DNA methylation level, revealed for the first time a significantly higher positivity in EpCAM-positive CTCs compared to plasma-derived exosomes. Future perspective of this study should be the evaluation of clinical utility of molecular biomarkers in CTCs and exosomes on independent multicentric cohorts with mCRPC patients. Full article
(This article belongs to the Special Issue Tumor Evolution: Progression, Metastasis and Therapeutic Response)
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Article
Soluble PD-L1 Is an Independent Prognostic Factor in Clear Cell Renal Cell Carcinoma
Cancers 2021, 13(4), 667; https://doi.org/10.3390/cancers13040667 - 07 Feb 2021
Cited by 12
Abstract
(1). Background: Immunohistochemical (IHC) evaluation of programmed death-1 (PD-1) and its ligand (PD-L1) is being used to evaluate advanced malignancies with potential response to immune checkpoint inhibitors. We evaluated both plasma and tissue expression of PD-1 and PD-L1 in the same cohort [...] Read more.
(1). Background: Immunohistochemical (IHC) evaluation of programmed death-1 (PD-1) and its ligand (PD-L1) is being used to evaluate advanced malignancies with potential response to immune checkpoint inhibitors. We evaluated both plasma and tissue expression of PD-1 and PD-L1 in the same cohort of patients, including non-metastatic and metastatic clear cell renal cell carcinoma (CCRCC). Concomitant plasma and tissue expression of PD-1 and PD-L1 was evaluated with emphasis on diagnostic and prognostic implications. (2) Methods: we analyzed PD-1 and PD-L1 IHC expression in tumor tissues and soluble forms (sPD-1 and sPD-L1) in plasma from 89 patients with CCRCC, of which 23 were metastatic and 16 received systemic therapy. The primary endpoint was evaluation of overall survival using Kaplan-Meier analysis and the Cox regression model. Plasma samples from healthy volunteers were also evaluated. (3) Results: Interestingly, sPD-1 and sPD-L1 levels were lower in cancer patients than in controls. sPD-1 and sPD-L1 levels and their counterpart tissue expression both at the tumor center and infiltrating front were not associated. Higher expression of both PD-1 and PD-L1 were associated with tumor grade, necrosis and tumor size. PD-1 was associated to tumor stage (pT) and PD-L1 to metastases. sPD-1 and sPD-L1 were not associated with clinico-pathological parameters, although both were higher in patients with synchronous metastases compared to metachronous ones and sPD-L1 was also higher for metastatic patients compared to non-metastatic patients. sPD-1 was also associated with the International Metastatic Renal Cell Cancer Database Consortium (IMDC) prognostic groups in metastatic CCRCC and also to the Morphology, Attenuation, Size and Structure (MASS) response criteria in metastatic patients treated with systemic therapy, mainly tyrosine-kinase inhibitors. Regarding prognosis, PD-L1 immunostaining at the tumor center with and without the tumor front was associated with worse survival, and so was sPD-L1 at a cut-off >793 ng/mL. Combination of positivity at both the tissue and plasma level increased the level of significance to predict prognosis. (4) Conclusions: Our findings corroborate the role of PD-L1 IHC to evaluate prognosis in CCRCC and present novel data on the usefulness of plasma sPD-L1 as a promising biomarker of survival in this neoplasia. Full article
(This article belongs to the Collection Clear Cell Renal Cell Carcinoma)
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Article
Radiomics-Derived Data by Contrast Enhanced Magnetic Resonance in RAS Mutations Detection in Colorectal Liver Metastases
Cancers 2021, 13(3), 453; https://doi.org/10.3390/cancers13030453 - 25 Jan 2021
Cited by 27
Abstract
Purpose: To assess the association of RAS mutation status and radiomics-derived data by Contrast Enhanced-Magnetic Resonance Imaging (CE-MRI) in liver metastases. Materials and Methods: 76 patients (36 women and 40 men; 59 years of mean age and 36–80 years as range) [...] Read more.
Purpose: To assess the association of RAS mutation status and radiomics-derived data by Contrast Enhanced-Magnetic Resonance Imaging (CE-MRI) in liver metastases. Materials and Methods: 76 patients (36 women and 40 men; 59 years of mean age and 36–80 years as range) were included in this retrospective study. Texture metrics and parameters based on lesion morphology were calculated. Per-patient univariate and multivariate analysis were made. Wilcoxon-Mann-Whitney U test, receiver operating characteristic (ROC) analysis, pattern recognition approaches with features selection approaches were considered. Results: Significant results were obtained for texture features while morphological parameters had not significant results to classify RAS mutation. The results showed that using a univariate analysis was not possible to discriminate accurately the RAS mutation status. Instead, considering a multivariate analysis and classification approaches, a KNN exclusively with texture parameters as predictors reached the best results (AUC of 0.84 and an accuracy of 76.9% with 90.0% of sensitivity and 67.8% of specificity on training set and an accuracy of 87.5% with 91.7% of sensitivity and 83.3% of specificity on external validation cohort). Conclusions: Texture parameters derived by CE-MRI and combined using multivariate analysis and patter recognition approaches could allow stratifying the patients according to RAS mutation status. Full article
(This article belongs to the Special Issue Radiology and Imaging of Cancer)
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Article
Senolytic Targeting of Bcl-2 Anti-Apoptotic Family Increases Cell Death in Irradiated Sarcoma Cells
Cancers 2021, 13(3), 386; https://doi.org/10.3390/cancers13030386 - 21 Jan 2021
Cited by 14
Abstract
Radiotherapy (RT) is a key component of cancer treatment. Most of the time, radiation is given after surgery but for soft-tissue sarcomas (STS), pre-surgical radiation is commonly utilized. However, despite improvements in RT accuracy, the rate of local recurrence remains high and is [...] Read more.
Radiotherapy (RT) is a key component of cancer treatment. Most of the time, radiation is given after surgery but for soft-tissue sarcomas (STS), pre-surgical radiation is commonly utilized. However, despite improvements in RT accuracy, the rate of local recurrence remains high and is the major cause of death for patients with STS. A better understanding of cell fates in response to RT could provide new therapeutic options to enhance tumour cell killing by RT and facilitate surgical resection. Here, we showed that irradiated STS cell cultures do not die but instead undergo therapy-induced senescence (TIS), which is characterized by proliferation arrest, senescence-associated β-galactosidase activity, secretion of inflammatory cytokines and persistent DNA damage. STS-TIS was also associated with increased levels of the anti-apoptotic Bcl-2 family of proteins which rendered cells targetable using senolytic Bcl-2 inhibitors. As oppose to radiation alone, the addition of senolytic agents Venetoclax (ABT-199) or Navitoclax (ABT-263) after irradiation induced a rapid apoptotic cell death in STS monolayer cultures and in a more complex three-dimensional culture model. Together, these data suggest a new promising therapeutic approach for sarcoma patients who receive neoadjuvant RT. The addition of senolytic agents to radiation treatments may significantly reduce tumour volume prior to surgery and thereby improve the clinical outcome of patients. Full article
(This article belongs to the Special Issue Sarcomas: New Biomarkers and Therapeutic Strategies)
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Article
Enhanced DNA Repair Pathway is Associated with Cell Proliferation and Worse Survival in Hepatocellular Carcinoma (HCC)
Cancers 2021, 13(2), 323; https://doi.org/10.3390/cancers13020323 - 17 Jan 2021
Cited by 20
Abstract
Hepatocellular carcinoma (HCC) is one of the most common malignancies and a leading cause of cancer-related deaths worldwide. In this study, a total of 749 HCC patients from 5 cohorts were studied to examine the relationships between enhancement of DNA repair and cancer [...] Read more.
Hepatocellular carcinoma (HCC) is one of the most common malignancies and a leading cause of cancer-related deaths worldwide. In this study, a total of 749 HCC patients from 5 cohorts were studied to examine the relationships between enhancement of DNA repair and cancer aggressiveness, tumor immune microenvironment, and patient survival in HCC, utilizing a DNA repair pathway score. Our findings suggest that the DNA repair pathway was not only enhanced by the stepwise carcinogenic process of HCC, but also significantly enhanced in grade 3 HCC compared with grade 1 and 2 tumors. DNA repair high HCC was associated with worse survival, elevated intratumor heterogeneity, and mutation load, but not with the fraction of immune cell infiltration nor immune response. HCC tumors with a DNA repair high score enriched the cell proliferation- and other cancer aggressiveness-related gene sets. Interestingly, these features were more pronounced in grade 1 and 2 HCC compared to grade 3 HCC. To our knowledge, this is the first study to use DNA repair pathway-related gene set expression data to examine and validate the clinical relevance of DNA repair pathway activity in HCC. The DNA repair score may be used to better understand and predict prognosis in HCC. Full article
(This article belongs to the Special Issue DNA Damage and Repair in Cancers)
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Article
Lidocaine Suppresses Viability and Migration of Human Breast Cancer Cells: TRPM7 as a Target for Some Breast Cancer Cell Lines
Cancers 2021, 13(2), 234; https://doi.org/10.3390/cancers13020234 - 10 Jan 2021
Cited by 17
Abstract
Background: The local anesthetic lidocaine suppresses some cancer cell lines but the mechanism is unclear. The melastatin-like transient receptor potential 7 (TRPM7) ion channel is aberrantly expressed in some cancers and may play a role in the disease. Hence, we suggested that lidocaine [...] Read more.
Background: The local anesthetic lidocaine suppresses some cancer cell lines but the mechanism is unclear. The melastatin-like transient receptor potential 7 (TRPM7) ion channel is aberrantly expressed in some cancers and may play a role in the disease. Hence, we suggested that lidocaine affects the viability and migration of breast cancer cells by regulating TRPM7. Methods: We measured the effects of lidocaine on TRPM7 function in HEK293 with exogenous TRPM7 expression (HEK-M7) using whole-cell patch-clamp and fura-2AM-based quench assay. We measured the effect of lidocaine on TRPM7 function, cell viability, and migration in TRPM7 expressing human breast cancer cell lines using fura-2AM-based quench, MTT, and wound-healing assays respectively. We compared cell viability and migration of wild type HEK293 cells (WT-HEK) with HEK-M7 and wild type MDA-MB-231 (WT-231) with TRPM7 knockout MDA-MB-231 (KO-231). Results: Lidocaine (1–3 mM) inhibited the viability and migration of all of these breast cancer cell lines. Functional evidence for TRPM7 was confirmed in the MDA-MB-231, AU565, T47D, and MDA-MB-468 cell lines where lidocaine at 0.3–3 mM suppressed the TRPM7 function. Lidocaine preferentially suppressed viability and migration of HEK-M7 over WT-HEK and WT-231 over KO-231. Conclusions: Lidocaine differentially reduced the viability and migration of human breast cancer cell lines tested. TRPM7 is one of the potential targets for the effects of lidocaine on viability and migration in MDA-MB-231, AU565, T47D, and MDA-MB-468. Full article
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Article
Alterations of NK Cell Phenotype in the Disease Course of Multiple Myeloma
Cancers 2021, 13(2), 226; https://doi.org/10.3390/cancers13020226 - 10 Jan 2021
Cited by 13
Abstract
Accumulating evidence demonstrates important roles for natural killer (NK) cells in controlling multiple myeloma (MM). A prospective flow cytometry-based analysis of NK cells in the blood and bone marrow (BM) of MM patient subgroups was performed (smoldering (SMM), newly diagnosed (ND), relapsed/refractory, (RR) [...] Read more.
Accumulating evidence demonstrates important roles for natural killer (NK) cells in controlling multiple myeloma (MM). A prospective flow cytometry-based analysis of NK cells in the blood and bone marrow (BM) of MM patient subgroups was performed (smoldering (SMM), newly diagnosed (ND), relapsed/refractory, (RR) and post-stem cell transplantation (pSCT)). Assessments included the biomarker expression and function of NK cells, correlations between the expression of receptors on NK cells with their ligands on myeloma cells, and comparisons between MM patient subgroups and healthy controls. The most striking differences from healthy controls were found in RR and pSCT patients, in which NK cells were less mature and expressed reduced levels of the activating receptors DNAM-1, NKG2D, and CD16. These differences were more pronounced in the BM than in blood, including upregulation of the therapeutic targets TIM3, TIGIT, ICOS, and GITR. Their expression suggests NK cells became exhausted upon chronic encounters with the tumor. A high expression of SLAMF7 on blood NK cells correlated with shorter progression-free survival. This correlation was particularly evident in ND patients, including on mature CD56dim NK cells in the BM. Thus, our NK cell analysis identified possible therapeutic targets in MM and a biomarker with prognostic potential for disease progression. Full article
(This article belongs to the Special Issue Tumor Microenvironment and Exacerbation Mechanism in Multiple Myeloma)
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Article
Presenting Features and Early Mortality from SARS-CoV-2 Infection in Cancer Patients during the Initial Stage of the COVID-19 Pandemic in Europe
Cancers 2020, 12(7), 1841; https://doi.org/10.3390/cancers12071841 - 08 Jul 2020
Cited by 42
Abstract
We describe the outcomes in cancer patients during the initial outbreak of the COVID-19 in Europe from the retrospective, multi-center observational OnCovid study. We identified 204 cancer patients from eight centers in the United Kingdom, Italy, and Spain aged >18 (mean = 69) [...] Read more.
We describe the outcomes in cancer patients during the initial outbreak of the COVID-19 in Europe from the retrospective, multi-center observational OnCovid study. We identified 204 cancer patients from eight centers in the United Kingdom, Italy, and Spain aged >18 (mean = 69) and diagnosed with COVID-19 between 26 February and 1 April 2020. A total of 127 (62%) were male, 184 (91%) had a diagnosis of solid malignancy, and 103 (51%) had non-metastatic disease. A total of 161 (79%) had >1 co-morbidity. A total of 141 (69%) patients had >1 COVID-19 complication. A total of 36 (19%) were escalated to high-dependency or intensive care. A total of 59 (29%) died, 53 (26%) were discharged, and 92 (45%) were in-hospital survivors. Mortality was higher in patients aged >65 (36% vs. 16%), in those with >2 co-morbidities (40% vs. 18%) and developing >1 complication from COVID-19 (38% vs. 4%, p = 0.004). Multi-variable analyses confirmed age > 65 and >2 co-morbidities to predict for patient mortality independent of tumor stage, active malignancy, or anticancer therapy. During the early outbreak of SARS-CoV-2 infection in Europe co-morbid burden and advancing age predicted for adverse disease course in cancer patients. The ongoing OnCovid study will allow us to compare risks and outcomes in cancer patients between the initial and later stages of the COVID-19 pandemic. Full article
(This article belongs to the Section Cancer Epidemiology and Prevention)
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Article
The Dynamic Relationship of Breast Cancer Cells and Fibroblasts in Fibronectin Accumulation at Primary and Metastatic Tumor Sites
Cancers 2020, 12(5), 1270; https://doi.org/10.3390/cancers12051270 - 17 May 2020
Cited by 50
Abstract
In breast cancer (BC), tissue stiffening via fibronectin (FN) and collagen accumulation is associated with advanced disease progression at both the primary tumor and metastatic sites. Here, we evaluate FN production in 15 BC cell lines, representing a variety of subtypes, phenotypes, metastatic [...] Read more.
In breast cancer (BC), tissue stiffening via fibronectin (FN) and collagen accumulation is associated with advanced disease progression at both the primary tumor and metastatic sites. Here, we evaluate FN production in 15 BC cell lines, representing a variety of subtypes, phenotypes, metastatic potentials, and chemotherapeutic sensitivities. We demonstrate that intracellular and soluble FN is initially lost during tumorigenic transformation but is rescued in all lines with epithelial-mesenchymal plasticity (EMP). Importantly, we establish that no BC cell line was able to independently organize a robust FN matrix. Non-transformed mammary epithelial cells were also unable to deposit FN matrices unless transglutaminase 2, a FN crosslinking enzyme, was overexpressed. Instead, BC cells manipulated the FN matrix production of fibroblasts in a phenotypic-dependent manner. In addition, varied accumulation levels were seen depending if the fibroblasts were conditioned to model paracrine signaling or endocrine signaling of the metastatic niche. In the former, fibroblasts conditioned by BC cultures with high EMP resulted in the largest FN matrix accumulation. In contrast, mesenchymal BC cells produced extracellular vesicles (EV) that resulted in the highest levels of matrix formation by conditioned fibroblasts. Overall, we demonstrate a dynamic relationship between tumor and stromal cells within the tumor microenvironment, in which the levels and fibrillarization of FN in the extracellular matrix are modulated during the particular stages of disease progression. Full article
(This article belongs to the Special Issue A Special Issue on Tumor Stroma )
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Article
A Novel 4-gene Score to Predict Survival, Distant Metastasis and Response to Neoadjuvant Therapy in Breast Cancer
Cancers 2020, 12(5), 1148; https://doi.org/10.3390/cancers12051148 - 02 May 2020
Cited by 37
Abstract
We generated a 4-gene score with genes upregulated in LM2-4, a metastatic variant of MDA-MB-231 (DOK 4, HCCS, PGF, and SHCBP1) that was strongly associated with disease-free survival (DFS) in TCGA cohort (hazard ratio [HR]>1.2, p < 0.02). The 4-gene score correlated with [...] Read more.
We generated a 4-gene score with genes upregulated in LM2-4, a metastatic variant of MDA-MB-231 (DOK 4, HCCS, PGF, and SHCBP1) that was strongly associated with disease-free survival (DFS) in TCGA cohort (hazard ratio [HR]>1.2, p < 0.02). The 4-gene score correlated with overall survival of TCGA (HR = 1.44, p < 0.001), which was validated with DFS and disease-specific survival of METABRIC cohort. The 4-gene score was able to predict worse survival or clinically aggressive tumors, such as high Nottingham pathological grade and advanced cancer staging. High score was associated with worse survival in the hormonal receptor (HR)-positive/Her2-negative subtype. High score enriched cell proliferation-related gene sets in GSEA. The score was high in primary tumors that originated, in and metastasized to, brain and lung, and it predicted worse progression-free survival for metastatic tumors. Good tumor response to neoadjuvant chemotherapy or hormonal therapy was accompanied by score reduction. High scores were also predictive of response to neoadjuvant chemotherapy for HR-positive/Her2-negative subtype. High score tumors had increased expression of T cell exhaustion marker genes, suggesting that the score may also be a biomarker for immunotherapy response. Our novel 4-gene score with both prognostic and predictive values may, therefore, be clinically useful particularly in HR-positive breast cancer. Full article
(This article belongs to the Collection Novel Biomarkers and Molecular Targets in Cancer)
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Article
Characterization of Human NK Cell-Derived Exosomes: Role of DNAM1 Receptor in Exosome-Mediated Cytotoxicity against Tumor
Cancers 2020, 12(3), 661; https://doi.org/10.3390/cancers12030661 - 12 Mar 2020
Cited by 41
Abstract
Despite the pivotal role of natural killer (NK) cells in defenses against tumors, their exploitation in cancer treatment is still limited due to their reduced ability to reaching tumor sites and the inhibitory effects of tumor microenvironment (TME) on their function. In this [...] Read more.
Despite the pivotal role of natural killer (NK) cells in defenses against tumors, their exploitation in cancer treatment is still limited due to their reduced ability to reaching tumor sites and the inhibitory effects of tumor microenvironment (TME) on their function. In this study, we have characterized the exosomes from IL2- or IL15-cultured human NK cells. Both cytokines induced comparable amounts of exosomes with similar cargo composition. Analysis of molecules contained within or exposed at the exosome surface, allowed the identification of molecules playing important roles in the NK cell function including IFN-γ, Lymphocyte Function-Associated Antigen (LFA-1), DNAX Accessory Molecule-1 (DNAM1) and Programmed Cell Death Protein (PD-1). Importantly, we show that DNAM1 is involved in exosome-mediated cytotoxicity as revealed by experiments using blocking antibodies to DNAM1 or DNAM1 ligands. In addition, antibody-mediated inhibition of exosome cytotoxicity results in a delay in target cell apoptosis. We also provide evidence that NK-exosomes may exert their cytolytic activity after short time interval and even at low concentrations. Regarding their possible use in immunotherapy, NK exosomes, detectable in peripheral blood, can diffuse into tissues and exert their cytolytic effect at tumor sites. This property offers a clue to integrate cancer treatments with NK exosomes. Full article
(This article belongs to the Special Issue Targeting Innate Immunity Cells in Cancer)
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Article
Predictive Value of Soluble PD-1, PD-L1, VEGFA, CD40 Ligand and CD44 for Nivolumab Therapy in Advanced Non-Small Cell Lung Cancer: A Case-Control Study
Cancers 2020, 12(2), 473; https://doi.org/10.3390/cancers12020473 - 18 Feb 2020
Cited by 34
Abstract
A large interindividual variability has been observed in anti Programmed cell Death 1 (anti-PD1) therapies efficacy. The aim of this study is to assess the correlation of soluble PD-1 (sPD-1), soluble Programmed cell Death Ligand 1 (sPD-L1), Vascular Endothelial Growth Factor A (VEGFA), [...] Read more.
A large interindividual variability has been observed in anti Programmed cell Death 1 (anti-PD1) therapies efficacy. The aim of this study is to assess the correlation of soluble PD-1 (sPD-1), soluble Programmed cell Death Ligand 1 (sPD-L1), Vascular Endothelial Growth Factor A (VEGFA), soluble CD40 ligand (sCD40L) and soluble CD44 (sCD44), with survival in nivolumab-treated metastatic non-small cell lung cancer (NSCLC) patients. Plasma biomarkers were assayed at baseline and after two cycles of nivolumab. A cut-off of positivity for sPD-1, sPD-L1 and sCD40L expressions was defined as a plasma level above the lower limit of quantification. Baseline sPD-1 and sPD-L1 levels were subsequently analyzed in a control group of EGFR-mutated (Epidermal Growth Factor Receptor) NSCLC patients. Association between survival and biomarkers was investigated using Cox proportional hazard regression model. Eighty-seven patients were included (51 nivolumab-treated patients, 36 in EGFR-mutated group). In nivolumab group, baseline sPD-1, sPD-L1 and sCD40L were positive for 15(29.4%), 27(52.9%) and 18(50%) patients, respectively. We defined a composite criteria (sCombo) corresponding to sPD-1 and/or sPD-L1 positivity for each patient. In nivolumab group, baseline sCombo positivity was associated with shorter median progression-free survival (PFS) (78 days 95%CI (55–109) vs. 658 days (222-not reached); HR: 4.12 (1.95–8.71), p = 0.0002) and OS (HR: 3.99(1.63–9.80), p = 0.003). In multivariate analysis, baseline sCombo independently correlated with PFS (HR: 2.66 (1.17–6.08), p = 0.02) but not OS. In EGFR-mutated group, all patients were baseline sCombo positive; therefore this factor was not associated with survival. After two cycles of nivolumab, an increased or stable sPD-1 level independently correlated with longer PFS (HR: 0.49, 95%CI (0.30–0.80), p = 0.004) and OS (HR: 0.39, 95%CI (0.21–0.71), p = 0.002). VEGFA, sCD40L and sCD44 did not correlate with survival. We propose a composite biomarker using sPD-1and sPDL-1 to predict nivolumab efficacy in NSCLC patients. A larger validation study is warranted. Full article
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Article
Venetoclax, a BCL-2 Inhibitor, Enhances the Efficacy of Chemotherapeutic Agents in Wild-Type ABCG2-Overexpression-Mediated MDR Cancer Cells
Cancers 2020, 12(2), 466; https://doi.org/10.3390/cancers12020466 - 18 Feb 2020
Cited by 33
Abstract
Previous studies have shown that small-molecule BCL-2 inhibitors can have a synergistic interaction with ABCG2 substrates in chemotherapy. Venetoclax is a potent and selective BCL-2 inhibitor, approved by the FDA in 2016 for the treatment of patients with chronic lymphocytic leukemia (CLL). This [...] Read more.
Previous studies have shown that small-molecule BCL-2 inhibitors can have a synergistic interaction with ABCG2 substrates in chemotherapy. Venetoclax is a potent and selective BCL-2 inhibitor, approved by the FDA in 2016 for the treatment of patients with chronic lymphocytic leukemia (CLL). This study showed that, at a non-toxic concentration, venetoclax at 10 µM significantly reversed multidrug resistance (MDR) mediated by wild-type ABCG2, without significantly affecting MDR mediated by mutated ABCG2 (R482G and R482T) and ABCB1, while moderate or no reversal effects were observed at lower concentrations (0.5 to 1 µM). The results showed that venetoclax increased the intracellular accumulation of chemotherapeutic agents, which was the result of directly blocking the wild-type ABCG2 efflux function and inhibiting the ATPase activity of ABCG2. Our study demonstrated that venetoclax potentiates the efficacy of wild-type ABCG2 substrate drugs. These findings may provide useful guidance in combination therapy against wild-type ABCG2-mediated MDR cancer in clinical practice. Full article
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Article
Multicenter External Validation of the Liverpool Uveal Melanoma Prognosticator Online: An OOG Collaborative Study
Cancers 2020, 12(2), 477; https://doi.org/10.3390/cancers12020477 - 18 Feb 2020
Cited by 18
Abstract
Uveal melanoma (UM) is fatal in ~50% of patients as a result of disseminated disease. This study aims to externally validate the Liverpool Uveal Melanoma Prognosticator Online V3 (LUMPO3) to determine its reliability in predicting survival after treatment for choroidal melanoma when utilizing [...] Read more.
Uveal melanoma (UM) is fatal in ~50% of patients as a result of disseminated disease. This study aims to externally validate the Liverpool Uveal Melanoma Prognosticator Online V3 (LUMPO3) to determine its reliability in predicting survival after treatment for choroidal melanoma when utilizing external data from other ocular oncology centers. Anonymized data of 1836 UM patients from seven international ocular oncology centers were analyzed with LUMPO3 to predict the 10-year survival for each patient in each external dataset. The analysts were masked to the patient outcomes. Model predictions were sent to an independent statistician to evaluate LUMPO3’s performance using discrimination and calibration methods. LUMPO3’s ability to discriminate between UM patients who died of metastatic UM and those who were still alive was fair-to-good, with C-statistics ranging from 0.64 to 0.85 at year 1. The pooled estimate for all external centers was 0.72 (95% confidence interval: 0.68 to 0.75). Agreement between observed and predicted survival probabilities was generally good given differences in case mix and survival rates between different centers. Despite the differences between the international cohorts of patients with primary UM, LUMPO3 is a valuable tool for predicting all-cause mortality in this disease when using data from external centers. Full article
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Article
Extracellular Vesicle microRNAs Contribute to the Osteogenic Inhibition of Mesenchymal Stem Cells in Multiple Myeloma
Cancers 2020, 12(2), 449; https://doi.org/10.3390/cancers12020449 - 14 Feb 2020
Cited by 32
Abstract
Osteolytic bone disease is the major complication associated with the progression of multiple myeloma (MM). Recently, extracellular vesicles (EVs) have emerged as mediators of MM-associated bone disease by inhibiting the osteogenic differentiation of human mesenchymal stem cells (hMSCs). Here, we investigated a correlation [...] Read more.
Osteolytic bone disease is the major complication associated with the progression of multiple myeloma (MM). Recently, extracellular vesicles (EVs) have emerged as mediators of MM-associated bone disease by inhibiting the osteogenic differentiation of human mesenchymal stem cells (hMSCs). Here, we investigated a correlation between the EV-mediated osteogenic inhibition and MM vesicle content, focusing on miRNAs. By the use of a MicroRNA Card, we identified a pool of miRNAs, highly expressed in EVs, from MM cell line (MM1.S EVs), expression of which was confirmed in EVs from bone marrow (BM) plasma of patients affected by smoldering myeloma (SMM) and MM. Notably,we found that miR-129-5p, which targets different osteoblast (OBs) differentiation markers, is enriched in MM-EVs compared to SMM-EVs, thus suggesting a selective packaging correlated with pathological grade. We found that miR-129-5p can be transported to hMSCs by MM-EVs and, by the use of miRNA mimics, we investigated its role in recipient cells. Our data demonstrated that the increase of miR-129-5p levels in hMSCs under osteoblastic differentiation stimuli inhibited the expression of the transcription factor Sp1, previously described as a positive modulator of osteoblastic differentiation, and of its target the Alkaline phosphatase (ALPL), thus identifying miR-129-5p among the players of vesicle-mediated bone disease. Full article
(This article belongs to the Special Issue Recent Advances on the Pathobiology and Treatment of Multiple Myeloma)
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Article
Expression of Tryptophan 2,3-Dioxygenase in Metastatic Uveal Melanoma
Cancers 2020, 12(2), 405; https://doi.org/10.3390/cancers12020405 - 10 Feb 2020
Cited by 24
Abstract
Uveal melanoma (UM) is the most common primary eye malignancy in adults and up to 50% of patients subsequently develop systemic metastasis. Metastatic uveal melanoma (MUM) is highly resistant to immunotherapy. One of the mechanisms for resistance would be the immune-suppressive tumor microenvironment. [...] Read more.
Uveal melanoma (UM) is the most common primary eye malignancy in adults and up to 50% of patients subsequently develop systemic metastasis. Metastatic uveal melanoma (MUM) is highly resistant to immunotherapy. One of the mechanisms for resistance would be the immune-suppressive tumor microenvironment. Here, we have investigated the role of tryptophan 2,3-dioxygenase (TDO) in UM. Both TDO and indoleamine 2,3-dioxygenase (IDO) catalyze tryptophan and produce kynurenine, which could cause inhibition of T cell immune responses. We first studied the expression of TDO on tumor tissue specimens obtained from UM hepatic metastasis. High expression of TDO protein was confirmed in all hepatic metastasis. TDO was positive in both normal hepatocytes and the tumor cells with relatively higher expression in tumor cells. On the other hand, IDO protein remained undetectable in all of the MUM specimens. UM cell lines established from metastasis also expressed TDO protein and increasing kynurenine levels were detected in the supernatant of MUM cell culture. In TCGA database, higher TDO2 expression in primary UM significantly correlated to BAP1 mutation and monosomy 3. These results indicate that TDO might be one of the key mechanisms for resistance to immunotherapy in UM. Full article
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Article
Early Detection of Hyperprogressive Disease in Non-Small Cell Lung Cancer by Monitoring of Systemic T Cell Dynamics
Cancers 2020, 12(2), 344; https://doi.org/10.3390/cancers12020344 - 04 Feb 2020
Cited by 40
Abstract
Hyperprogressive disease (HPD) is an adverse outcome of immunotherapy consisting of an acceleration of tumor growth associated with prompt clinical deterioration. The definitions based on radiological evaluation present important technical limitations. No biomarkers have been identified yet. In this study, 70 metastatic NSCLC [...] Read more.
Hyperprogressive disease (HPD) is an adverse outcome of immunotherapy consisting of an acceleration of tumor growth associated with prompt clinical deterioration. The definitions based on radiological evaluation present important technical limitations. No biomarkers have been identified yet. In this study, 70 metastatic NSCLC patients treated with anti-PD-1/PD-L1 immunotherapy after progression to platinum-based therapy were prospectively studied. Samples from peripheral blood were obtained before the first (baseline) and second cycles of treatment. Peripheral blood mononuclear cells (PBMCs) were isolated and differentiation stages of CD4 lymphocytes quantified by flow cytometry and correlated with HPD as identified with radiological criteria. A strong expansion of highly differentiated CD28 CD4 T lymphocytes (CD4 THD) between the first and second cycle of therapy was observed in HPD patients. After normalizing, the proportion of posttreatment/pretreatment CD4 THD was significantly higher in HPD when compared with the rest of patients (median 1.525 vs. 0.990; p = 0.0007), and also when stratifying by HPD, non-HPD progressors, and responders (1.525, 1.000 and 0.9700 respectively; p = 0.0025). A cut-off value of 1.3 identified HPD with 82% specificity and 70% sensitivity. An increase of CD28 CD4 T lymphocytes ≥ 1.3 (CD4 THD burst) was significantly associated with HPD (p = 0.008). The tumor growth ratio (TGR) was significantly higher in patients with expansion of CD4 THD burst compared to the rest of patients (median 2.67 vs. 0.86, p = 0.0049), and also when considering only progressors (median 2.67 vs. 1.03, p = 0.0126). A strong expansion of CD28 CD4 lymphocytes in peripheral blood within the first cycle of therapy is an early differential feature of HPD in NSCLC treated with immune-checkpoint inhibitors. The monitoring of T cell dynamics allows the early detection of this adverse outcome in clinical practice and complements radiological evaluation. Full article
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Article
Targeting CD47 as a Novel Immunotherapy for Multiple Myeloma
Cancers 2020, 12(2), 305; https://doi.org/10.3390/cancers12020305 - 28 Jan 2020
Cited by 31
Abstract
Multiple myeloma (MM) remains to be incurable despite recent therapeutic advances. CD47, an immune checkpoint known as the “don’t eat me” signal, is highly expressed on the surface of various cancers, allowing cancer cells to send inhibitory signals to macrophages and impede phagocytosis [...] Read more.
Multiple myeloma (MM) remains to be incurable despite recent therapeutic advances. CD47, an immune checkpoint known as the “don’t eat me” signal, is highly expressed on the surface of various cancers, allowing cancer cells to send inhibitory signals to macrophages and impede phagocytosis and immune response. In this study, we hypothesized that blocking the “don’t eat me” signaling using an anti-CD47 monoclonal antibody will induce killing of MM cells. We report that CD47 expression was directly correlated with stage of the disease, from normal to MGUS to MM. Moreover, MM cells had remarkably higher CD47 expression than other cell populations in the bone marrow. These findings indicate that CD47 is specifically expressed on MM and can be used as a potential therapeutic target. Further, blocking of CD47 using an anti-CD47 antibody induced immediate activation of macrophages, which resulted in induction of phagocytosis and killing of MM cells in the 3D-tissue engineered bone marrow model, as early as 4 hours. These results suggest that macrophage checkpoint immunotherapy by blocking the CD47 “don’t eat me” signal is a novel and promising strategy for the treatment of MM, providing a basis for additional studies to validate these effects in vivo and in patients. Full article
(This article belongs to the Special Issue Recent Advances on the Pathobiology and Treatment of Multiple Myeloma)
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Article
Cancer Stem Cell Marker DCLK1 Correlates with Tumorigenic Immune Infiltrates in the Colon and Gastric Adenocarcinoma Microenvironments
Cancers 2020, 12(2), 274; https://doi.org/10.3390/cancers12020274 - 22 Jan 2020
Cited by 27
Abstract
Immunotherapy that has proven efficacy in several solid cancers plays a partial role in improving clinical outcomes of advanced gastrointestinal (GI) cancers. There is an unmet need to find new immune-related therapeutic targets. Doublecortin-like kinase 1 (DCLK1) marks tuft cells which are recognized [...] Read more.
Immunotherapy that has proven efficacy in several solid cancers plays a partial role in improving clinical outcomes of advanced gastrointestinal (GI) cancers. There is an unmet need to find new immune-related therapeutic targets. Doublecortin-like kinase 1 (DCLK1) marks tuft cells which are recognized as cancer-initiating cells and regulators of the type II immune response, and has been studied for its role in many cancers including colon and gastric cancers, but its role in tumor immunity remains unexplored. In the current study, we analyzed colon and gastric cancer RNA sequencing data from 283 and 415 patients, respectively, from The Cancer Genome Atlas (TCGA). High DCLK1 expression predicted the worse clinical outcomes in colon and gastric cancer patients and correlated with increased immune and stromal components. Further analysis indicated that DCLK1 was strongly linked to infiltration of multiple immune cell types, especially TAMs and Treg, and strongly correlated with increased CD8+ T cell inhibitors TGFB1 and CXCL12 and their receptors, suggesting it may contribute to TAM-mediated inhibition of CD8+ T cells. Interestingly, we found that DCLK1 was a prognostic biomarker in left-sided colon cancer, which has worse outcomes and demonstrates a reduced response to existing immunotherapies. In conclusion, our results demonstrate that DCLK1 is linked with functional regulation of the tumor microenvironment and may have potential as a prognostic biomarker and adjuvant target to promote immunotherapy sensitivity in colon and gastric cancer patients. Full article
(This article belongs to the Collection Mechanism of Immunotherapy in Cancers)
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Article
Metformin as Potential Therapy for High-Grade Glioma
Cancers 2020, 12(1), 210; https://doi.org/10.3390/cancers12010210 - 15 Jan 2020
Cited by 27
Abstract
Metformin (MET), 1,1-dimethylbiguanide hydrochloride, is a biguanide drug used as the first-line medication in the treatment of type 2 diabetes. The recent years have brought many observations showing metformin in its new role. The drug, commonly used in the therapy of diabetes, may [...] Read more.
Metformin (MET), 1,1-dimethylbiguanide hydrochloride, is a biguanide drug used as the first-line medication in the treatment of type 2 diabetes. The recent years have brought many observations showing metformin in its new role. The drug, commonly used in the therapy of diabetes, may also find application in the therapy of a vast variety of tumors. Its effectiveness has been demonstrated in colon, breast, prostate, pancreatic cancer, leukemia, melanoma, lung and endometrial carcinoma, as well as in gliomas. This is especially important in light of the poor options offered to patients in the case of high-grade gliomas, which include glioblastoma (GBM). A thorough understanding of the mechanism of action of metformin can make it possible to discover new drugs that could be used in neoplasm therapy. Full article
(This article belongs to the Special Issue Recent Advances in Glioblastoma)
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Article
Polyphyllin VI Induces Caspase-1-Mediated Pyroptosis via the Induction of ROS/NF-κB/NLRP3/GSDMD Signal Axis in Non-Small Cell Lung Cancer
Cancers 2020, 12(1), 193; https://doi.org/10.3390/cancers12010193 - 13 Jan 2020
Cited by 74
Abstract
Trillium tschonoskii Maxim (TTM), a traditional Chinese medicine, has been demonstrated to have a potent anti-tumor effect. Recently, polyphyllin VI (PPVI), a main saponin isolated from TTM, was reported by us to significantly suppress the proliferation of non-small cell lung cancer (NSCLC) via [...] Read more.
Trillium tschonoskii Maxim (TTM), a traditional Chinese medicine, has been demonstrated to have a potent anti-tumor effect. Recently, polyphyllin VI (PPVI), a main saponin isolated from TTM, was reported by us to significantly suppress the proliferation of non-small cell lung cancer (NSCLC) via the induction of apoptosis and autophagy in vitro and in vivo. In this study, we further found that the NLRP3 inflammasome was activated in PPVI administrated A549-bearing athymic nude mice. As is known to us, pyroptosis is an inflammatory form of caspase-1-dependent programmed cell death that plays an important role in cancer. By using A549 and H1299 cells, the in vitro effect and action mechanism by which PPVI induces activation of the NLRP3 inflammasome in NSCLC were investigated. The anti-proliferative effect of PPVI in A549 and H1299 cells was firstly measured and validated by MTT assay. The activation of the NLRP3 inflammasome was detected by using Hoechst33324/PI staining, flow cytometry analysis and real-time live cell imaging methods. We found that PPVI significantly increased the percentage of cells with PI signal in A549 and H1299, and the dynamic change in cell morphology and the process of cell death of A549 cells indicated that PPVI induced an apoptosis-to-pyroptosis switch, and, ultimately, lytic cell death. In addition, belnacasan (VX-765), an inhibitor of caspase-1, could remarkably decrease the pyroptotic cell death of PPVI-treated A549 and H1299 cells. Moreover, by detecting the expression of NLRP3, ASC, caspase-1, IL-1β, IL-18 and GSDMD in A549 and h1299 cells using Western blotting, immunofluorescence imaging and flow cytometric analysis, measuring the caspase-1 activity using colorimetric assay, and quantifying the cytokines level of IL-1β and IL-18 using ELISA, the NLRP3 inflammasome was found to be activated in a dose manner, while VX-765 and necrosulfonamide (NSA), an inhibitor of GSDMD, could inhibit PPVI-induced activation of the NLRP3 inflammasome. Furthermore, the mechanism study found that PPVI could activate the NF-κB signaling pathway via increasing reactive oxygen species (ROS) levels in A549 and H1299 cells, and N-acetyl-L-cysteine (NAC), a scavenger of ROS, remarkably inhibited the cell death, and the activation of NF-κB and the NLRP3 inflammasome in PPVI-treated A549 and H1299 cells. Taken together, these data suggested that PPVI-induced, caspase-1-mediated pyroptosis via the induction of the ROS/NF-κB/NLRP3/GSDMD signal axis in NSCLC, which further clarified the mechanism of PPVI in the inhibition of NSCLC, and thereby provided a possibility for PPVI to serve as a novel therapeutic agent for NSCLC in the future. Full article
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Article
Tivantinib, A c-Met Inhibitor in Clinical Trials, Is Susceptible to ABCG2-Mediated Drug Resistance
Cancers 2020, 12(1), 186; https://doi.org/10.3390/cancers12010186 - 12 Jan 2020
Cited by 25
Abstract
Tivantinib, also known as ARQ-197, is a potent non-ATP competitive selective c-Met inhibitor currently under phase 3 clinical trial evaluation for liver and lung cancers. In this study, we explored factors that may lead to tivantinib resistance, especially in regards to its interaction [...] Read more.
Tivantinib, also known as ARQ-197, is a potent non-ATP competitive selective c-Met inhibitor currently under phase 3 clinical trial evaluation for liver and lung cancers. In this study, we explored factors that may lead to tivantinib resistance, especially in regards to its interaction with ATP-binding cassette super-family G member 2 (ABCG2). ABCG2 is one of the most important members of the ATP-binding cassette (ABC) transporter family, a group of membrane proteins that play a critical role in mediating multidrug resistance (MDR) in a variety of cancers, including those of the liver and lung. Tivantinib received a high score in docking analysis, indicating a strong interaction between tivantinib and ABCG2, and an ATPase assay indicated that tivantinib stimulated ABCG2 ATPase activity in a concentration-dependent manner. An MTT assay showed that ABCG2 overexpression significantly desensitized both the cancer cells and ABCG2 transfected-HEK293 cells to tivantinib and that this drug resistance can be reversed by ABCG2 inhibitors. Furthermore, tivantinib upregulated the protein expression of ABCG2 without altering the cell surface localization of ABCG2, leading to increased resistance to substrate drugs, such as mitoxantrone. Altogether, these data demonstrate that tivantinib is a substrate of ABCG2, and, therefore, ABCG2 overexpression may decrease its therapeutic effect. Our study provides evidence that the overexpression of ABCG2 should be monitored in clinical settings as an important risk factor for tivantinib drug resistance. Full article
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Article
Predictors of Response and Survival in Immune Checkpoint Inhibitor-Treated Unresectable Hepatocellular Carcinoma
Cancers 2020, 12(1), 182; https://doi.org/10.3390/cancers12010182 - 11 Jan 2020
Cited by 36
Abstract
Immune checkpoint inhibitors (ICIs) with nivolumab and pembrolizumab are promising agents for advanced hepatocellular carcinoma (HCC) but lack of effective biomarkers. We aimed to investigate the potential predictors of response and factors associated with overall survival (OS) for ICI treatment in unresectable HCC [...] Read more.
Immune checkpoint inhibitors (ICIs) with nivolumab and pembrolizumab are promising agents for advanced hepatocellular carcinoma (HCC) but lack of effective biomarkers. We aimed to investigate the potential predictors of response and factors associated with overall survival (OS) for ICI treatment in unresectable HCC patients. Ninety-five patients who received nivolumab or pembrolizumab for unresectable HCC were enrolled for analyses. Radiologic evaluation was based on RECIST v1.1. Factors associated with outcomes were analyzed. Of 90 patients with evaluable images, the objective response rate (ORR) was 24.4%. Patients at Child–Pugh A or received combination treatment had higher ORR. Early alpha-fetoprotein (AFP) >10% reduction (within 4 weeks) was the only independent predictor of best objective response (odds ratio: 7.259, p = 0.001). For patients with baseline AFP ≥10 ng/mL, significantly higher ORR (63.6% vs. 10.2%, p < 0.001) and disease control rate (81.8% vs. 14.3%, p < 0.001) were observed in those with early AFP reduction than those without. In addition, early AFP reduction and albumin-bilirubin (ALBI) grade or Child–Pugh class were independent factors associated with OS in different models. In conclusion, a 10-10 rule of early AFP response can predict objective response and survival to ICI treatment in unresectable HCC. ALBI grade and Child–Pugh class determines survival by ICI treatment. Full article
(This article belongs to the Special Issue Immunotherapy in Hepatocellular Carcinoma)
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Article
The Role of Transient Receptor Potential Melastatin 7 (TRPM7) in Cell Viability: A Potential Target to Suppress Breast Cancer Cell Cycle
Cancers 2020, 12(1), 131; https://doi.org/10.3390/cancers12010131 - 04 Jan 2020
Cited by 27
Abstract
The divalent cation-selective channel transient receptor potential melastatin 7 (TRPM7) channel was shown to affect the proliferation of some types of cancer cell. However, the function of TRPM7 in the viability of breast cancer cells remains unclear. Here we show that TRPM inhibitors [...] Read more.
The divalent cation-selective channel transient receptor potential melastatin 7 (TRPM7) channel was shown to affect the proliferation of some types of cancer cell. However, the function of TRPM7 in the viability of breast cancer cells remains unclear. Here we show that TRPM inhibitors suppressed the viability of TRPM7-expressing breast cancer cells. We first demonstrated that the TRPM7 inhibitors 2-aminoethyl diphenylborinate (2-APB), ginsenoside Rd (Gin Rd), and waixenicin A preferentially suppressed the viability of human embryonic kidney HEK293 overexpressing TRPM7 (HEK-M7) cells over wildtype HEK293 (WT-HEK). Next, we confirmed the effects of 2-APB on the TRPM7 channel functions by whole-cell currents and divalent cation influx. The inhibition of the viability of HEK-M7 cells by 2-APB was not mediated by the increase in cell death but by the interruption of the cell cycle. Similar to HEK-M7 cells, the viability of TRPM7-expressing human breast cancer MDA-MB-231, AU565, and T47D cells were also suppressed by 2-APB by arresting the cell cycle in the S phase. Furthermore, in a novel TRPM7 knock-out MDA-MB-231 (KO-231) cell line, decreased divalent influx and reduced proliferation were observed compared to the wildtype MDA-MB-231 cells. 2-APB and Gin Rd preferentially suppressed the viability of wildtype MDA-MB-231 cells over KO-231 by affecting the cell cycle in wildtype but not KO-231 cells. Our results suggest that TRPM7 regulates the cell cycle of breast cancers and is a potential therapeutic target. Full article
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Article
High-Throughput Label-Free Isolation of Heterogeneous Circulating Tumor Cells and CTC Clusters from Non-Small-Cell Lung Cancer Patients
Cancers 2020, 12(1), 127; https://doi.org/10.3390/cancers12010127 - 03 Jan 2020
Cited by 31
Abstract
(1) Background: Circulating tumor cell (CTC) clusters are emerging as clinically significant harbingers of metastases in solid organ cancers. Prior to engaging these CTC clusters in animal models of metastases, it is imperative for technology to identify them with high sensitivity. These clusters [...] Read more.
(1) Background: Circulating tumor cell (CTC) clusters are emerging as clinically significant harbingers of metastases in solid organ cancers. Prior to engaging these CTC clusters in animal models of metastases, it is imperative for technology to identify them with high sensitivity. These clusters often present heterogeneous surface markers and current methods for isolation of clusters may fall short. (2) Methods: We applied an inertial microfluidic Labyrinth device for high-throughput, biomarker-independent, size-based isolation of CTCs/CTC clusters from patients with metastatic non-small-cell lung cancer (NSCLC). (3) Results: Using Labyrinth, CTCs (PanCK+/DAPI+/CD45−) were isolated from patients (n = 25). Heterogeneous CTC populations, including CTCs expressing epithelial (EpCAM), mesenchymal (Vimentin) or both markers were detected. CTCs were isolated from 100% of patients (417 ± 1023 CTCs/mL). EpCAM− CTCs were significantly greater than EpCAM+ CTCs. Cell clusters of ≥2 CTCs were observed in 96% of patients—of which, 75% were EpCAM−. CTCs revealed identical genetic aberrations as the primary tumor for RET, ROS1, and ALK genes using fluorescence in situ hybridization (FISH) analysis. (4) Conclusions: The Labyrinth device recovered heterogeneous CTCs in 100% and CTC clusters in 96% of patients with metastatic NSCLC. The majority of recovered CTCs/clusters were EpCAM−, suggesting that these would have been missed using traditional antibody-based capture methods. Full article
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Article
Switching to Immune Checkpoint Inhibitors upon Response to Targeted Therapy; The Road to Long-Term Survival in Advanced Melanoma Patients with Highly Elevated Serum LDH?
Cancers 2019, 11(12), 1940; https://doi.org/10.3390/cancers11121940 - 04 Dec 2019
Cited by 20
Abstract
The prognosis of patients with advanced melanoma has improved dramatically. However, the clinical outcomes of patients with highly elevated serum lactate dehydrogenase (LDH) remain very poor. The aim of this study was to explore whether patients with normalized LDH after targeted therapy could [...] Read more.
The prognosis of patients with advanced melanoma has improved dramatically. However, the clinical outcomes of patients with highly elevated serum lactate dehydrogenase (LDH) remain very poor. The aim of this study was to explore whether patients with normalized LDH after targeted therapy could benefit from subsequent treatment with immune checkpoint inhibitors (ICI). Data from all patients with BRAF-mutant metastatic melanoma with a highly elevated serum LDH at baseline (≥2× upper limit of normal) receiving first-line targeted therapy between 2012 and 2019 in the Netherlands were collected. Patients were stratified according to response status to targeted therapy and change in LDH at start of subsequent treatment with ICI. Differences in overall survival (OS) between the subgroups were compared using log-rank tests. After a median follow-up of 35.1 months, median OS of the total study population (n = 360) was 4.9 months (95% CI 4.4–5.4). Of all patients receiving subsequent treatment with ICI (n = 113), survival from start of subsequent treatment was significantly longer in patients who had normalized LDH and were still responding to targeted therapy compared to those with LDH that remained elevated (median OS 24.7 vs. 1.1 months). Our study suggests that introducing ICI upon response to targeted therapy with normalization of LDH could be an effective strategy in obtaining long-term survival in advanced melanoma patients with initial highly elevated serum LDH. Full article
(This article belongs to the Special Issue Advanced Melanoma)
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Article
Hyperprogressive Disease during Anti-PD-1 (PDCD1) / PD-L1 (CD274) Therapy: A Systematic Review and Meta-Analysis
Cancers 2019, 11(11), 1699; https://doi.org/10.3390/cancers11111699 - 01 Nov 2019
Cited by 48
Abstract
Hyperprogressive disease (HPD) is a recently acknowledged pattern of rapid tumor progression after the initiation of immune checkpoint inhibitors. HPD has been observed across various types of tumors and has been associated with poor survival. We performed a meta-analysis to identify baseline (i.e., [...] Read more.
Hyperprogressive disease (HPD) is a recently acknowledged pattern of rapid tumor progression after the initiation of immune checkpoint inhibitors. HPD has been observed across various types of tumors and has been associated with poor survival. We performed a meta-analysis to identify baseline (i.e., prior to programmed cell death 1 [PD-1, PDCD1] / programmed cell death 1 ligand 1 [PD-L1, CD274] inhibitor therapy) patient factors associated with risks of developing HPD during PD-1/PD-L1 inhibitor therapy. We searched eight databases until 6 June 2019. We calculated the summary odds ratio (OR) and its 95% confidence interval (CI) using the random-effects model and explored between-study heterogeneity and small-study effects. A total of nine articles was eligible (217 HPD cases, 1519 cancer patients) for meta-analysis. There was no standard definition of HPD, and the incidence of HPD ranged from 1 to 30%. We identified twenty-three baseline patient factors, of which five factors were statistically significantly associated with HPD. These were serum lactate dehydrogenase (LDH) above the upper normal limit (OR = 1.89, 95% CI = 1.02–3.49, p = 0.043), more than two metastatic sites (OR = 1.86, 1.34–2.57, p < 0.001), liver metastases (OR = 3.33, 2.07–5.34, p < 0.001), Royal Marsden Hospital prognostic score of 2 or above (OR = 3.33, 1.96–5.66, p < 0.001), and positive PD-L1 expression status that was inversely correlated with HPD (OR = 0.60, 0.36–0.99, p = 0.044). Between-study heterogeneity was low. Evidence of small-study effect was found in one association (PD-L1 expression). Subset analyses of patients with non-small cell lung cancer showed similar results. Future studies are warranted to identify underlying molecular mechanisms and to test their roles as predictive biomarkers of HPD. Full article
(This article belongs to the Special Issue Cancer Biomarkers)
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Article
Comprehensive Metabolomic Search for Biomarkers to Differentiate Early Stage Hepatocellular Carcinoma from Cirrhosis
Cancers 2019, 11(10), 1497; https://doi.org/10.3390/cancers11101497 - 06 Oct 2019
Cited by 29
Abstract
The established biomarker for hepatocellular carcinoma (HCC), serum α-fetoprotein (AFP), has suboptimal performance in early disease stages. This study aimed to develop a metabolite panel to differentiate early-stage HCC from cirrhosis. Cross-sectional metabolomic analyses of serum samples were performed for 53 and 47 [...] Read more.
The established biomarker for hepatocellular carcinoma (HCC), serum α-fetoprotein (AFP), has suboptimal performance in early disease stages. This study aimed to develop a metabolite panel to differentiate early-stage HCC from cirrhosis. Cross-sectional metabolomic analyses of serum samples were performed for 53 and 47 patients with early HCC and cirrhosis, respectively, and 50 matched healthy controls. Results were validated in 82 and 80 patients with early HCC and cirrhosis, respectively. To retain a broad spectrum of metabolites, technically distinct analyses (global metabolomic profiling using gas chromatography time-of-flight mass spectrometry and targeted analyses using liquid chromatography with tandem mass spectrometry) were employed. Multivariate analyses classified distinct metabolites; logistic regression was employed to construct a prediction model for HCC diagnosis. Five metabolites (methionine, proline, ornithine, pimelylcarnitine, and octanoylcarnitine) were selected in a panel. The panel distinguished HCC from cirrhosis and normal controls, with an area under the receiver operating curve (AUC) of 0.82; this was significantly better than that of AFP (AUC: 0.75). During validation, the panel demonstrated significantly better predictability (AUC: 0.94) than did AFP (AUC: 0.78). Defects in ammonia recycling, the urea cycle, and amino acid metabolism, demonstrated on enrichment pathway analysis, may reliably distinguish HCC from cirrhosis. Compared with AFP alone, the metabolite panel substantially improved early-stage HCC detection. Full article
(This article belongs to the Special Issue Human Hepatocellular Carcinoma (HCC))
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Article
STAT3 Activity Promotes Programmed-Death Ligand 1 Expression and Suppresses Immune Responses in Breast Cancer
Cancers 2019, 11(10), 1479; https://doi.org/10.3390/cancers11101479 - 01 Oct 2019
Cited by 34
Abstract
Signal transducer and activator of transcription 3 (STAT3) is an oncogene and multifaceted transcription factor involved in multiple cellular functions. Its role in modifying anti-tumor immunity has been recently recognized. In this study, the biologic effects of STAT3 on immune checkpoint expression and [...] Read more.
Signal transducer and activator of transcription 3 (STAT3) is an oncogene and multifaceted transcription factor involved in multiple cellular functions. Its role in modifying anti-tumor immunity has been recently recognized. In this study, the biologic effects of STAT3 on immune checkpoint expression and anti-tumor responses were investigated in breast cancer (BC). A transcriptional signature of phosphorylated STAT3 was positively correlated with PD-L1 expression in two independent cohorts of early BC. Pharmacologic inhibition and gene silencing of STAT3 led to decreased Programmed Death Ligand 1 (PD-L1) expression levels in vitro, and resulted as well in reduction of tumor growth and decreased metastatic dissemination in a mammary carcinoma mouse model. The hampering of tumor progression was correlated to an anti-tumoral macrophage phenotype and accumulation of natural-killer cells, but also in reduced accrual of cytotoxic lymphocytes. In human BC, pro-tumoral macrophages correlated to PD-L1 expression, proliferation status and higher grade of malignancy, indicating a subset of patients with immunosuppressive properties. In conclusion, this study provides evidence for STAT3-mediated regulation of PD-L1 and modulation of immune microenvironment in BC. Full article
(This article belongs to the Special Issue Targeting STAT3 and STAT5 in Cancer)
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Article
Increased Plasmatic Levels of PSA-Expressing Exosomes Distinguish Prostate Cancer Patients from Benign Prostatic Hyperplasia: A Prospective Study
Cancers 2019, 11(10), 1449; https://doi.org/10.3390/cancers11101449 - 27 Sep 2019
Cited by 33
Abstract
Prostate Specific Antigen (PSA) fails to discriminate between benign prostatic hyperplasia (BPH) and Prostate Cancer (PCa), resulting in large numbers of unnecessary biopsies and missed cancer diagnoses. Nanovesicles called exosomes are directly detectable in patient plasma and here we explore the potential use [...] Read more.
Prostate Specific Antigen (PSA) fails to discriminate between benign prostatic hyperplasia (BPH) and Prostate Cancer (PCa), resulting in large numbers of unnecessary biopsies and missed cancer diagnoses. Nanovesicles called exosomes are directly detectable in patient plasma and here we explore the potential use of plasmatic exosomes expressing PSA (Exo-PSA) in distinguishing healthy individuals, BPH, and PCa. Exosomes were obtained from plasma samples of 80 PCa, 80 BPH, and 80 healthy donors (CTR). Nanoparticle Tracking Analysis (NTA), immunocapture-based ELISA (IC-ELISA), and nanoscale flow-cytometry (NSFC), were exploited to detect and characterize plasmatic exosomes. Statistical analysis showed that plasmatic exosomes expressing both CD81 and PSA were significantly higher in PCa as compared to both BPH and CTR, reaching 100% specificity and sensitivity in distinguishing PCa patients from healthy individuals. IC-ELISA, NSFC, and Exo-PSA consensus score (EXOMIX) showed 98% to 100% specificity and sensitivity for BPH-PCa discrimination. This study outperforms the conventional PSA test with a minimally invasive widely exploitable approach. Full article
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Article
CD8+ and Regulatory T cells Differentiate Tumor Immune Phenotypes and Predict Survival in Locally Advanced Head and Neck Cancer
Cancers 2019, 11(9), 1398; https://doi.org/10.3390/cancers11091398 - 19 Sep 2019
Cited by 31
Abstract
Background: The tumor immune status “inflamed”, “immune excluded”, and “desert” might serve as a predictive parameter. We studied these three cancer immune phenotypes while using a simple immunohistochemical algorithm. Methods: Pre-treatment tissue samples of 280 patients with locally advanced HNSCC treated with radiochemotherapy [...] Read more.
Background: The tumor immune status “inflamed”, “immune excluded”, and “desert” might serve as a predictive parameter. We studied these three cancer immune phenotypes while using a simple immunohistochemical algorithm. Methods: Pre-treatment tissue samples of 280 patients with locally advanced HNSCC treated with radiochemotherapy were analyzed. A double staining of CD8+ cytotoxic T cells (CTL) and FoxP3+ (Treg) was performed and the cell density was evaluated in the intraepithelial and stromal compartment of the tumor. Results: The classification of tumors as “immune desert” when stromal CTL were ≤ 50 cells/mm2, “inflamed” when intraepithelial CTL were > 500 cells/mm2, and as “excluded” when neither of these definitions met these cut off values allowed the best discrimination regarding overall survival. These groups had median OS periods of 37, 61, and 85 months, respectively. In “immune desert” and “immune excluded” tumors high Treg tended to worsen OS, but in “inflamed” tumors high Treg clearly improved OS. Conclusions: We propose that, in locally advanced HNSCC, the tumor immune state “inflamed”, “immune excluded”, and “immune desert” can be defined by intraepithelial and stromal CTL. Tregs can further subdivide these groups. The opposing effects of Tregs in the different groups might be the reason for the inconsistency of Tregs prognostic values published earlier. Full article
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Article
Mir526b and Mir655 Promote Tumour Associated Angiogenesis and Lymphangiogenesis in Breast Cancer
Cancers 2019, 11(7), 938; https://doi.org/10.3390/cancers11070938 - 04 Jul 2019
Cited by 39
Abstract
MicroRNAs (miRNAs) are small endogenously produced RNAs, which regulate growth and development, and oncogenic miRNA regulate tumor growth and metastasis. Tumour-associated angiogenesis and lymphangiogenesis are processes involving the release of growth factors from tumour cells into the microenvioronemnt to communicate with endothelial cells [...] Read more.
MicroRNAs (miRNAs) are small endogenously produced RNAs, which regulate growth and development, and oncogenic miRNA regulate tumor growth and metastasis. Tumour-associated angiogenesis and lymphangiogenesis are processes involving the release of growth factors from tumour cells into the microenvioronemnt to communicate with endothelial cells to induce vascular propagation. Here, we examined the roles of cyclo-oxygenase (COX)-2 induced miR526b and miR655 in tumour-associated angiogenesis and lymphangiogenesis. Ectopic overexpression of miR526b and miR655 in poorly metastatic estrogen receptor (ER) positive MCF7 breast cancer cells resulted in upregulation of angiogenesis and lymphangiogenesis markers vascular endothelial growth factor A (VEGFA); VEGFC; VEGFD; COX-2; lymphatic vessel endothelial hyaluronan receptor-1 (LYVE1); and receptors VEGFR1, VEGFR2, and EP4. Further, miRNA-high cell free conditioned media promoted migration and tube formation by human umbilical vein endothelial cells (HUVECs), and upregulated VEGFR1, VEGFR2, and EP4 expression, showing paracrine stimulation of miRNA in the tumor microenvironment. The miRNA-induced migration and tube formation phenotypes were abrogated with EP4 antagonist or PI3K/Akt inhibitor treatments, confirming the involvement of the EP4 and PI3K/Akt pathway. Tumour supressor gene PTEN was found to be downregulated in miRNA high cells, confirming that it is a target of both miRNAs. PTEN inhibits hypoxia-inducible factor-1 (HIF1α) and the PI3K/Akt pathway, and loss of regulation of these pathways through PTEN results in upregulation of VEGF expression. Moreover, in breast tumors, angiogenesis marker VEGFA and lymphangiogenesis marker VEGFD expression was found to be significantly higher compared with non-adjacent control, and expression of miR526b and miR655 was positively correlated with VEGFA, VEGFC, VEGFD, CD31, and LYVE1 expression in breast tumour samples. These findings further strengthen the role of miRNAs as breast cancer biomarkers and EP4 as a potential therapeutic target to abrogate miRNA-induced angiogenesis and lymphangiogenesis in breast cancer. Full article
(This article belongs to the Special Issue Role of miRNAs in Cancer—Analysis of Their Targetome)
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Gene Expression Comparison between the Lymph Node-Positive and -Negative Reveals a Peculiar Immune Microenvironment Signature and a Theranostic Role for WNT Targeting in Pancreatic Ductal Adenocarcinoma: A Pilot Study
Cancers 2019, 11(7), 942; https://doi.org/10.3390/cancers11070942 - 04 Jul 2019
Cited by 59
Abstract
Over the past several years there has been much debate with regards to the prognostic and clinical significance of pancreatic ductal adenocarcinoma (PDAC) with lymph nodes metastasis. The PDAC gene expression knowledge and the biologic alterations underlying the lymph node involvement convey a [...] Read more.
Over the past several years there has been much debate with regards to the prognostic and clinical significance of pancreatic ductal adenocarcinoma (PDAC) with lymph nodes metastasis. The PDAC gene expression knowledge and the biologic alterations underlying the lymph node involvement convey a clinical implication in dealing with the theranostic window. To this end, we provide an original bioinformatic dissection of the gene expression differences of PDAC according to the nodal involvement from a large public available dataset. Comprehensive transcriptomic analysis from 143 RNA-seq patient’s derived samples indicated that WNT increased activation and a peculiar immune microenvironment identify subjects with nodal involvement. In frame of this thinking, we validated the WNT pathway role in increasing the likelihood of lymphatic dissemination in vitro. Moreover, we demonstrated for the first time in a PDAC model the potential therapeutic window that XAV-939—a specific WNT pathway inhibitor—has in re-educating a tumor-permissive immune system. Finally, we outline the potential implication on bystander molecular drivers exerted by WNT molecular inhibition, providing a picture of the proteomic oncogenic landscape changes elicited by XAV-939 on PDAC cells and their clinical implication. Our findings hold the promise to identify novel immune-based therapeutic strategies targeting WNT to enhance PDAC cytotoxicity and restore anti-PDAC immunity in node-positive disease. Full article
(This article belongs to the Special Issue Advances in Pancreatic Cancer Research)
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Article
Determination of PD-L1 Expression in Circulating Tumor Cells of NSCLC Patients and Correlation with Response to PD-1/PD-L1 Inhibitors
Cancers 2019, 11(6), 835; https://doi.org/10.3390/cancers11060835 - 17 Jun 2019
Cited by 67
Abstract
Circulating tumor cells (CTCs) hold great potential to answer key questions of how non-small cell lung cancer (NSCLC) evolves and develops resistance upon anti-PD-1/PD-L1 treatment. Currently, their clinical utility in NSCLC is compromised by a low detection rate with the established, Food and [...] Read more.
Circulating tumor cells (CTCs) hold great potential to answer key questions of how non-small cell lung cancer (NSCLC) evolves and develops resistance upon anti-PD-1/PD-L1 treatment. Currently, their clinical utility in NSCLC is compromised by a low detection rate with the established, Food and Drug Administration (FDA)-approved, EpCAM-based CellSearch® System. We tested an epitope-independent method (ParsortixTM system) and utilized it to assess PD-L1 expression of CTCs from NSCLC patients. We prospectively collected 127 samples, 97 of which were analyzed with the epitope-independent system in comparison to the CellSearch system. CTCs were determined by immunocytochemistry as intact, nucleated, CD45, pankeratins (K)+ cells. PD-L1 status of CTCs was evaluated from 89 samples. With the epitope-independent system, ≥1 CTC per blood sample was detected in 59 samples (61%) compared to 31 samples (32%) with the EpCAM-based system. Upon PD-L1 staining, 47% of patients harbored only PD-L1+CTCs, 47% had PD-L1+ and PD-L1CTCs, and only 7% displayed exclusively PD-L1CTCs. The percentage of PD-L1+CTCs did not correlate with the percentage of PD-L1+ in biopsies determined by immunohistochemistry (p = 0.179). Upon disease progression, all patients showed an increase in PD-L1+CTCs, while no change or a decrease in PD-L1+CTCs was observed in responding patients (n = 11; p = 0.001). Our data show a considerable heterogeneity in the PD-L1 status of CTCs from NSCLC patients. An increase of PD-L1+CTCs holds potential to predict resistance to PD-1/PD-L1 inhibitors. Full article
(This article belongs to the Special Issue Liquid Biopsy for Cancer)
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Article
Taxol-Loaded MSC-Derived Exosomes Provide a Therapeutic Vehicle to Target Metastatic Breast Cancer and Other Carcinoma Cells
Cancers 2019, 11(6), 798; https://doi.org/10.3390/cancers11060798 - 09 Jun 2019
Cited by 90
Abstract
MSC-derived exosomes display, among others, an efficient biocompatibility and a reduced intrinsic immunogenicity, representing a valuable vehicle for drug delivery in a tumor-therapeutic approach. Following treatment of several human mesenchymal stroma/stem-like cell (MSC) populations with sub-lethal concentrations of taxol for 24 h, exosomes [...] Read more.
MSC-derived exosomes display, among others, an efficient biocompatibility and a reduced intrinsic immunogenicity, representing a valuable vehicle for drug delivery in a tumor-therapeutic approach. Following treatment of several human mesenchymal stroma/stem-like cell (MSC) populations with sub-lethal concentrations of taxol for 24 h, exosomes were isolated and applied to different human cancer populations including A549 lung cancer, SK-OV-3 ovarian cancer, and MDA-hyb1 breast cancer cells. While MSC control exosomes revealed little if any growth inhibition on the tumor cells, exposure to taxol-loaded MSC-derived exosomes was associated with 80–90% cytotoxicity. A similar application of taxol-loaded exosomes from HuVEC displayed much fewer effects. Quantification by LC-MS/MS analysis demonstrated a 7.6-fold reduced taxol concentration in MSC exosomes when compared to equivalent cytotoxic in vitro effects achieved with taxol substances, indicating a specific and more efficient tumor-targeting property. Consequently, MSC-derived taxol exosomes were tested in vivo. Highly metastatic MDA-hyb1 breast tumors were induced in NODscid mice, and systemic intravenous application of MSC-derived taxol exosomes revealed a more than 60% reduction of subcutaneous primary tumors. Moreover, the amount of distant organ metastases observed at least in lung, liver, spleen, and kidney was reduced by 50% with MSC taxol exosomes, similar to the effects observed with taxol, although the concentration of taxol in exosomes was about 1000-fold reduced. Together, these findings in different cancer cell populations and in vivo provide promising future perspectives for drug-loaded MSC-derived exosomes in efficiently targeting primary tumors and metastases by reducing side effects. Full article
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CAR T-Cells Targeting the Integrin αvβ6 and Co-Expressing the Chemokine Receptor CXCR2 Demonstrate Enhanced Homing and Efficacy against Several Solid Malignancies
Cancers 2019, 11(5), 674; https://doi.org/10.3390/cancers11050674 - 14 May 2019
Cited by 70
Abstract
Despite the unprecedented clinical success of chimeric antigen receptors (CAR) T-cells against haematological malignancy, solid tumors impose a far greater challenge to success. Largely, this stems from an inadequate capacity of CAR T-cells that can traffic and maintain function within a hostile microenvironment. [...] Read more.
Despite the unprecedented clinical success of chimeric antigen receptors (CAR) T-cells against haematological malignancy, solid tumors impose a far greater challenge to success. Largely, this stems from an inadequate capacity of CAR T-cells that can traffic and maintain function within a hostile microenvironment. To enhance tumor-directed T-cell trafficking, we have engineered CAR T-cells to acquire heightened responsiveness to interleukin (IL)-8. Circulating IL-8 levels correlate with disease burden and prognosis in multiple solid tumors in which it exerts diverse pathological functions including angiogenesis, support of cancer stem cell survival, and recruitment of immunosuppressive myeloid cells. To harness tumor-derived IL-8 for therapeutic benefit, we have co-expressed either of its cognate receptors (CXCR1 or CXCR2) in CAR T-cells that target the tumor-associated αvβ6 integrin. We demonstrate here that CXCR2-expressing CAR T-cells migrate more efficiently towards IL-8 and towards tumor conditioned media that contains this cytokine. As a result, these CAR T-cells elicit superior anti-tumor activity against established αvβ6-expressing ovarian or pancreatic tumor xenografts, with a more favorable toxicity profile. These data support the further engineering of CAR T-cells to acquire responsiveness to cancer-derived chemokines in order to improve their therapeutic activity against solid tumors. Full article
(This article belongs to the Special Issue The Role of Integrins in Cancer)
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Article
Head and Body/Tail Pancreatic Carcinomas Are Not the Same Tumors
Cancers 2019, 11(4), 497; https://doi.org/10.3390/cancers11040497 - 08 Apr 2019
Cited by 39
Abstract
The association between pancreatic ductal adenocarcinoma (PDAC) location (head vs. Body/Tail (B/T)) and clinical outcome remains controversial. We collected clinicopathological and gene expression data from 249 resected PDAC samples from public data sets, and we compared data between 208 head and 41 B/T [...] Read more.
The association between pancreatic ductal adenocarcinoma (PDAC) location (head vs. Body/Tail (B/T)) and clinical outcome remains controversial. We collected clinicopathological and gene expression data from 249 resected PDAC samples from public data sets, and we compared data between 208 head and 41 B/T samples. The 2-year overall survival (OS) was better for the head than for the B/T PDACs (44 vs. 27%, p = 0.043), especially when comparing tumors with similar TNM classification (T3/4N0M0: 67% vs. 17%, p = 0.002) or from the same molecular class (squamous subtype: 31% vs. 0%, p < 0.0001). Bailey’s molecular subtypes were differentially distributed within the two groups, with the immunogenic subtype being underrepresented in the “B/T” group (p = 0.005). Uni- and multivariate analyses indicated that PDAC anatomic location was an independent prognostic factor. Finally, the supervised analysis identified 334 genes differentially expressed. Genes upregulated in the “head” group suggested lymphocyte activation and pancreas exocrine functions. Genes upregulated in the “B/T” group were related to keratinocyte differentiation, in line with the enrichment for squamous phenotype. We identified a robust gene expression signature (GES) associated with B/T PDAC location, suggesting that head and B/T PDAC are different. This GES could serve as an indicator for differential therapeutic management based on PDAC location. Full article
(This article belongs to the Special Issue Advances in Pancreatic Cancer Research)
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Article
The Flavonoid Metabolite 2,4,6-Trihydroxybenzoic Acid Is a CDK Inhibitor and an Anti-Proliferative Agent: A Potential Role in Cancer Prevention
Cancers 2019, 11(3), 427; https://doi.org/10.3390/cancers11030427 - 26 Mar 2019
Cited by 25
Abstract
Flavonoids have emerged as promising compounds capable of preventing colorectal cancer (CRC) due to their anti-oxidant and anti-inflammatory properties. It is hypothesized that the metabolites of flavonoids are primarily responsible for the observed anti-cancer effects owing to the unstable nature of the parent [...] Read more.
Flavonoids have emerged as promising compounds capable of preventing colorectal cancer (CRC) due to their anti-oxidant and anti-inflammatory properties. It is hypothesized that the metabolites of flavonoids are primarily responsible for the observed anti-cancer effects owing to the unstable nature of the parent compounds and their degradation by colonic microflora. In this study, we investigated the ability of one metabolite, 2,4,6-trihydroxybenzoic acid (2,4,6-THBA) to inhibit Cyclin Dependent Kinase (CDK) activity and cancer cell proliferation. Using in vitro kinase assays, we demonstrated that 2,4,6-THBA dose-dependently inhibited CDKs 1, 2 and 4 and in silico studies identified key amino acids involved in these interactions. Interestingly, no significant CDK inhibition was observed with the structurally related compounds 3,4,5-trihydroxybenzoic acid (3,4,5-THBA) and phloroglucinol, suggesting that orientation of the functional groups and specific amino acid interactions may play a role in inhibition. We showed that cellular uptake of 2,4,6-THBA required the expression of functional SLC5A8, a monocarboxylic acid transporter. Consistent with this, in cells expressing functional SLC5A8, 2,4,6-THBA induced CDK inhibitory proteins p21Cip1 and p27Kip1 and inhibited cell proliferation. These findings, for the first time, suggest that the flavonoid metabolite 2,4,6-THBA may mediate its effects through a CDK- and SLC5A8-dependent pathway contributing to the prevention of CRC. Full article
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Article
The Small Molecule Ephrin Receptor Inhibitor, GLPG1790, Reduces Renewal Capabilities of Cancer Stem Cells, Showing Anti-Tumour Efficacy on Preclinical Glioblastoma Models
Cancers 2019, 11(3), 359; https://doi.org/10.3390/cancers11030359 - 13 Mar 2019
Cited by 25
Abstract
Therapies against glioblastoma (GBM) show a high percentage of failure associated with the survival of glioma stem cells (GSCs) that repopulate treated tumours. Forced differentiation of GSCs is a promising new approach in cancer treatment. Erythropoietin-producing hepatocellular (Eph) receptors drive tumourigenicity and stemness [...] Read more.
Therapies against glioblastoma (GBM) show a high percentage of failure associated with the survival of glioma stem cells (GSCs) that repopulate treated tumours. Forced differentiation of GSCs is a promising new approach in cancer treatment. Erythropoietin-producing hepatocellular (Eph) receptors drive tumourigenicity and stemness in GBM. We tested GLPG1790, a first small molecule with inhibition activity versus inhibitor of various Eph receptor kinases, in preclinical GBM models using in vitro and in vivo assays. GLPG1790 rapidly and persistently inhibited Ephrin-A1-mediated phosphorylation of Tyr588 and Ser897, completely blocking EphA2 receptor signalling. Similarly, this compound blocks the ephrin B2-mediated EphA3 and EphB4 tyrosine phosphorylation. This resulted in anti-glioma effects. GLPG1790 down-modulated the expression of mesenchymal markers CD44, Sox2, nestin, octamer-binding transcription factor 3/4 (Oct3/4), Nanog, CD90, and CD105, and up-regulated that of glial fibrillary acidic protein (GFAP) and pro-neural/neuronal markers, βIII tubulin, and neurofilaments. GLPG1790 reduced tumour growth in vivo. These effects were larger compared to radiation therapy (RT; U251 and T98G xenografts) and smaller than those of temozolomide (TMZ; U251 and U87MG cell models). By contrast, GLPG1790 showed effects that were higher than Radiotherapy (RT) and similar to Temozolomide (TMZ) in orthotopic U87MG and CSCs-5 models in terms of disease-free survival (DFS) and overall survival (OS). Further experiments were necessary to study possible interactions with radio- and chemotherapy. GLPG1790 demonstrated anti-tumor effects regulating both the differentiative status of Glioma Initiating Cells (GICs) and the quality of tumor microenvironment, translating into efficacy in aggressive GBM mouse models. Significant common molecular targets to radio and chemo therapy supported the combination use of GLPG1790 in ameliorative antiglioma therapy. Full article
(This article belongs to the Special Issue Glioblastoma: State of the Art and Future Perspectives)
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Article
CAFs and TGF-β Signaling Activation by Mast Cells Contribute to Resistance to Gemcitabine/Nabpaclitaxel in Pancreatic Cancer
Cancers 2019, 11(3), 330; https://doi.org/10.3390/cancers11030330 - 07 Mar 2019
Cited by 58
Abstract
Tumor–stroma interactions are of key importance for pancreatic ductal adenocarcinoma (PDAC) progression. Our aim was to investigate whether cancer associated fibroblasts (CAFs) and mast cells (MC) affected the sensitivity of PDAC cells to gemcitabine/nabpaclitaxel (GEM/NAB). For this purpose, the combination cytotoxicity and the [...] Read more.
Tumor–stroma interactions are of key importance for pancreatic ductal adenocarcinoma (PDAC) progression. Our aim was to investigate whether cancer associated fibroblasts (CAFs) and mast cells (MC) affected the sensitivity of PDAC cells to gemcitabine/nabpaclitaxel (GEM/NAB). For this purpose, the combination cytotoxicity and the effect on tumor invasion and angiogenesis were evaluated with or without a conditioned medium from the mast cell line HMC-1 (human mast cell line-1 cells) and CAFs. Beside the clinical outcome of a homogenous population of PDAC patients, receiving GEM/NAB, was correlated to the circulating levels of mast cell tryptase and to a panel of inflammatory and immunosuppressive cytokines. CAFs neither affected drugs’ cytotoxicity nor the inhibition of angiogenesis, but promoted tumor cell invasion. The MC instead, caused resistance to drugs by reducing apoptosis, by activating the TGF-β signalling and by promoting tumor invasion. Indeed, the inhibition of TβRI serine/threonine kinase activity by galunisertib restored drugs cytotoxicity. Moreover, MC induced the release of TGF-β1, and increased expression of PAR-2, ERK1/2 and Akt activation. Accordingly, TGF-β1, tryptase and other pro-inflammatory and immunosuppressive cytokines increased in the unresponsive patients. In conclusion, MC play a pivotal role in the resistance to GEM/NAB. A correlation between high level of circulating pro-inflammatory/ immunosuppressive cytokines and unresponsiveness was found in PDAC patients. Full article
(This article belongs to the Special Issue Advances in Pancreatic Cancer Research)
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Article
Pan-Cancer Analyses Reveal Genomic Features of FOXM1 Overexpression in Cancer
Cancers 2019, 11(2), 251; https://doi.org/10.3390/cancers11020251 - 21 Feb 2019
Cited by 70
Abstract
FOXM1 is frequently overexpressed in cancer, but this has not been studied in a comprehensive manner. We utilized genotype-tissue expression (GTEx) normal and The Cancer Genome Atlas (TCGA) tumor data to define FOXM1 expression, including its isoforms, and to determine the genetic alterations [...] Read more.
FOXM1 is frequently overexpressed in cancer, but this has not been studied in a comprehensive manner. We utilized genotype-tissue expression (GTEx) normal and The Cancer Genome Atlas (TCGA) tumor data to define FOXM1 expression, including its isoforms, and to determine the genetic alterations that promote FOXM1 expression in cancer. Additionally, we used human fallopian tube epithelial (FTE) cells to dissect the role of Retinoblastoma (Rb)-E2F and Cyclin E1 in FOXM1 regulation, and a novel human embryonic kidney cell (HEK293T) CRISPR FOXM1 knockout model to define isoform-specific transcriptional programs. FOXM1 expression, at the mRNA and protein level, was significantly elevated in tumors with FOXM1 amplification, p53 inactivation, and Rb-E2F deregulation. FOXM1 expression was remarkably high in testicular germ cell tumors (TGCT), high-grade serous ovarian cancer (HGSC), and basal breast cancer (BBC). FOXM1 expression in cancer was associated with genomic instability, as measured using aneuploidy signatures. FTE models confirmed a role for Rb-E2F signaling in FOXM1 regulation and in particular identified Cyclin E1 as a novel inducer of FOXM1 expression. Among the three FOXM1 isoforms, FOXM1c showed the highest expression in normal and tumor tissues and cancer cell lines. The CRISPR knockout model demonstrated that FOXM1b and FOXM1c are transcriptionally active, while FOXM1a is not. Finally, we were unable to confirm the existence of a FOXM1 auto-regulatory loop. This study provides significant and novel information regarding the frequency, causes, and consequences of elevated FOXM1 expression in human cancer. Full article
(This article belongs to the Special Issue Fox Proteins and Cancers: Old Proteins with Emerging New Tales)
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Article
Capture of Circulating Tumour Cell Clusters Using Straight Microfluidic Chips
Cancers 2019, 11(1), 89; https://doi.org/10.3390/cancers11010089 - 14 Jan 2019
Cited by 56
Abstract
Circulating tumour cells (CTCs) are the metastatic precursors to distant disease in head and neck cancers (HNCs). Whilst the prognostic and predictive value of single CTCs have been well documented, the role of CTC clusters, which potentially have a higher metastatic capacity are [...] Read more.
Circulating tumour cells (CTCs) are the metastatic precursors to distant disease in head and neck cancers (HNCs). Whilst the prognostic and predictive value of single CTCs have been well documented, the role of CTC clusters, which potentially have a higher metastatic capacity are limited. In this study, the authors used a novel straight microfluidic chip to focus and capture CTCs. The chip offers high cell recoveries with clinically relevant numbers (10–500 cells/mL) without the need for further purification. Single CTCs were identified in 10/21 patient samples (range 2–24 CTCs/mL), CTC clusters in 9/21 patient samples (range 1–6 CTC clusters/mL) and circulating tumour microemboli (CTM) in 2/21 samples. This study demonstrated that CTC clusters contain EGFR amplified single CTCs within the cluster volume. This novel microfluidic chip demonstrates the efficient sorting and preservation of single CTCs, CTC clusters and CTMs. The authors intend to expand this study to a larger cohort to determine the clinical implication of the CTC subsets in HNC. Full article
(This article belongs to the Special Issue Liquid Biopsy for Cancer)
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Article
Spectrum of Epithelial-Mesenchymal Transition Phenotypes in Circulating Tumour Cells from Early Breast Cancer Patients
Cancers 2019, 11(1), 59; https://doi.org/10.3390/cancers11010059 - 09 Jan 2019
Cited by 31
Abstract
Circulating tumour cells (CTCs) can provide valuable prognostic information in a number of epithelial cancers. However, their detection is hampered due to their molecular heterogeneity, which can be induced by the epithelial-mesenchymal transition (EMT) process. Therefore, current knowledge about CTCs from clinical samples [...] Read more.
Circulating tumour cells (CTCs) can provide valuable prognostic information in a number of epithelial cancers. However, their detection is hampered due to their molecular heterogeneity, which can be induced by the epithelial-mesenchymal transition (EMT) process. Therefore, current knowledge about CTCs from clinical samples is often limited due to an inability to isolate wide spectrum of CTCs phenotypes. In the current work, we aimed at isolation and molecular characterization of CTCs with different EMT status in order to establish their clinical significance in early breast cancer patients. We have obtained CTCs-enriched blood fraction from 83 breast cancer patients in which we have tested the expression of epithelial, mesenchymal and general breast cancer CTCs markers (MGB1/HER2/CK19/CDH1/CDH2/VIM/PLS3), cancer stem cell markers (CD44, NANOG, ALDH1, OCT-4, CD133) and cluster formation gene (plakoglobin). We have shown that in the CTCs-positive patients, epithelial, epithelial-mesenchymal and mesenchymal CTCs markers were detected at a similar rate (in 28%, 24% and 24%, respectively). Mesenchymal CTCs were characterized by the most aggressive phenotype (significantly higher expression of CXCR4, uPAR, CD44, NANOG, p < 0.05 for all), presence of lymph node metastases (p = 0.043), larger tumour size (p = 0.023) and 7.33 higher risk of death in the multivariate analysis (95% CI 1.06–50.41, p = 0.04). Epithelial-mesenchymal subtype, believed to correspond to highly plastic and aggressive state, did not show significant impact on survival. Gene expression profile of samples with epithelial-mesenchymal CTCs group resembled pure epithelial or pure mesenchymal phenotypes, possibly underlining degree of EMT activation in particular patient’s sample. Molecular profiling of CTCs EMT phenotype provides more detailed and clinically informative results, proving the role of EMT in malignant cancer progression in early breast cancer. Full article
(This article belongs to the Special Issue Circulating Tumor Cells (CTCs))
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Article
Oxymatrine Attenuates Tumor Growth and Deactivates STAT5 Signaling in a Lung Cancer Xenograft Model
Cancers 2019, 11(1), 49; https://doi.org/10.3390/cancers11010049 - 07 Jan 2019
Cited by 57
Abstract
Oxymatrine (OMT) is a major alkaloid found in radix Sophorae flavescentis extract and has been reported to exhibit various pharmacological activities. We elucidated the detailed molecular mechanism(s) underlying the therapeutic actions of OMT in non-small cell lung cancer (NSCLC) cells and a xenograft [...] Read more.
Oxymatrine (OMT) is a major alkaloid found in radix Sophorae flavescentis extract and has been reported to exhibit various pharmacological activities. We elucidated the detailed molecular mechanism(s) underlying the therapeutic actions of OMT in non-small cell lung cancer (NSCLC) cells and a xenograft mouse model. Because the STAT5 signaling cascade has a significant role in regulating cell proliferation and survival in tumor cells, we hypothesized that OMT may disrupt this signaling cascade to exert its anticancer effects. We found that OMT can inhibit the constitutive activation of STAT5 by suppressing the activation of JAK1/2 and c-Src, nuclear localization, as well as STAT5 binding to DNA in A549 cells and abrogated IL-6-induced STAT5 phosphorylation in H1299 cells. We also report that a sub-optimal concentration of OMT when used in combination with a low dose of paclitaxel produced significant anti-cancer effects by inhibiting cell proliferation and causing substantial apoptosis. In a preclinical lung cancer mouse model, OMT when used in combination with paclitaxel produced a significant reduction in tumor volume. These results suggest that OMT in combination with paclitaxel can cause an attenuation of lung cancer growth both in vitro and in vivo. Full article
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Article
Effects of SAHA and EGCG on Growth Potentiation of Triple-Negative Breast Cancer Cells
Cancers 2019, 11(1), 23; https://doi.org/10.3390/cancers11010023 - 27 Dec 2018
Cited by 37
Abstract
Triple-negative breast cancer comprises approximately 15–20% of all breast cancers diagnosed and is nearly twice as common in black women than white women in the United States. We evaluated the effects of two epigenetic-modifying compounds on markers of growth potential in several triple-negative [...] Read more.
Triple-negative breast cancer comprises approximately 15–20% of all breast cancers diagnosed and is nearly twice as common in black women than white women in the United States. We evaluated the effects of two epigenetic-modifying compounds on markers of growth potential in several triple-negative breast cancer cell lines. Suberoylanilide hydroxamic acid (SAHA), a histone deacetylase (HDAC) inhibitor currently used in the treatment of cutaneous T cell lymphoma, was administered to triple-negative breast cancer cells alone or in combination with epigallocatechin-3-gallate (EGCG), a DNA methyltransferase (DNMT) inhibitor isolated from green tea. The compounds affected the expression of oncogenic miR-221/222 and tumor suppressors, p27 and PTEN, in addition to estrogen receptor alpha (ERα). E-cadherin expression was increased while N-cadherin was decreased, indicating a more epithelial phenotype. In addition, the activity of DNMTs was diminished with the treatments, and there was a significant enrichment of AcH3 within the promoter of p27 and PTEN, suggesting a role of epigenetic mechanisms for the aforementioned changes. These results translated to reduced migration of the triple-negative breast cancer cells with the treatments. Together, these findings support the role of SAHA and EGCG in limiting growth and proliferation of breast cancer cells. Full article
(This article belongs to the Special Issue Epigenetic Influence on Cancer Metastasis and/or Treatment Resistance)
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