Search Results (101)

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with high recurrence rates even after curative resection and adjuvant chemotherapy. Although immunotherapeutic approaches, such as immune checkpoint blockade (ICB), have revolutionized the treatment of some solid tumor malignancies, this has not been the case for PDAC. Several characteristics of PDAC, including its distinctive desmoplastic tumor microenvironment (TME), intratumor heterogeneity, and poor antigenicity and immune cell infiltration, contribute to its dismal immunotherapeutic landscape. Cancer vaccines offer one approach to overcoming these barriers, particularly in the resectable or borderline resectable settings, where tumor burden is low and immunosuppression is less pronounced. Various vaccination platforms have been tested in the clinical setting, from off-the-shelf peptide-based vaccines (e.g., AMPLFIFY-201 study, where over 80% of participants exhibited T-cell and biomarker responses) to personalized neoantigen mRNA vaccine approaches (e.g., autogene cevumeran, with significant responders experiencing longer median recurrence-free survival (RFS)). The key considerations for enhancing the efficacy of vaccination include combinations with chemotherapy, radiotherapy, and/or ICBs, as well as selecting appropriate immunomodulators or adjuvants. Recent results suggest that with continued mechanistic advancement and novel therapeutic development, cancer vaccines may finally be poised for clinical success in PDAC. Full article

Background/Objective: Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer death and tumors with an extremely poor prognosis. In the present study, novel biomarker candidates useful for the early diagnosis and prognosis of human invasive PDAC were investigated. Methods: Biomarker candidates were first selected based on the proteomic/bioinformatic and clinico-pathological analyses of 10 and 100 patients with PDAC, respectively, operated at Osaka Metropolitan University Hospital (Exp. 1). Next, the expression and secretion of the target protein and its EV mRNA were investigated in pancreatic cancer cells in vitro and in a Balb/c nude mouse model. In addition, the protein and EV mRNA levels of candidate molecules were measured in the blood serum of 36 PDAC and 10 IPMN patients, and diagnostic significance was assessed (Exp. 2). Results: A significant elevation of peroxiredoxin 3 (PRX3), a mitochondrial matrix protein, was found in PDAC via LC-Ms/Ms analysis. In Exp. 1, PRX3 overexpression was found in PDAC and PanIN lesions and was associated with a tumor infiltrative growth pattern (INFc) and poor overall 1-year patient survival. The prognostic value was significantly improved when PRX3 was combined with serum SPan-1 and DUPAN-2 markers in survival analyses. Furthermore, the PRX3 protein and its extracellular vesicle (EV: exosome and oncosome)-incorporated mRNA were secreted at detectable levels from PANC-1, MIAPaCa-2, and SW1990 cells into the blood of Balb/c nude mice bearing tumors. The overexpression of PRX3 was positively correlated with that of cancer stem cell marker CD44 variant 9 (CD44v9), P-Nrf2, and FOXO3a, as well as the generation of reactive oxygen species. In Exp. 2, a significant increase in PRX3 protein and EV mRNA was detected in the blood serum of PDAC subjects compared to IPMN patients and healthy controls. Significantly higher PRX3 protein levels were found in the IPMN group. The elevation of PRX3 EV mRNA was significantly associated with poor patient survival. Conclusions: These results indicate that PRX3 may become a novel early biomarker for PDAC diagnosis and prognosis. Full article

Pancreatic ductal adenocarcinoma (PDAC) typically exhibits asymptomatic clinical features, with most patients diagnosed at an advanced metastatic stage. Current treatment options are limited to cytotoxic standard therapies, primarily FOLFIRINOX or modified FOLFIRINOX regimens. This highlights a critical need for targeted therapies to improve efficacy and reduce toxicity. We have sought to identify potential biomarkers based on DNA methylation profiles to identify patient groupings with improved overall survival (OS) based on the Transforming Growth Factor Beta (TGFB) gene complex, and the interferon-related pathway gene, IFI27, using the TCGA dataset for PDAC patients. We employed a multivariate Cox proportional hazards model to directly compare hazard ratios for TGFB1/2/3 and IFI27 methylation impacting OS. We also controlled for age at diagnosis, sex, and TGFB2 gene methylation by examining the statistical interactions between the marker gene mRNA expression and the TGFB2 gene. Genes were filtered based on the tumor-specific expression patterns and Cox models with highly significant interaction terms to identify mRNA expression of genes that amplified the impact of TGFB2 methylation. The effect of the TGFB2 gene methylation in the context of marker gene mRNA expression was analyzed using Kaplan–Meier (KM) analysis. Marker genes were correlated to T-cell enrichment patterns using the deconvolution algorithms provided by the TIMER 2.0 database. Methylation of TGFB2, TGFB3 and IFI27 genes using median cut-off values for KM plots showed significant improvements in median overall survival of 5.7 (p = 0.044), 5.2 (p = 0.036), and 3.7 (p = 0.028) months for high methylation levels for TGFB2, IFI27, and TGFB3 genes, respectively. In contrast, high levels of TGFB1 methylation exhibited a shorter 4.7 (p = 0.016) month median OS time. The impact of TGFB2 methylation was amplified at low expressions of marker genes that were highly correlated with CD8⁺ T-cell infiltration. Patients with high levels of TGFB2 methylation when compared to low levels of TGFB2 methylation showed median overall survival (OS) improvements at low mRNA expression levels: 54.2 months for CD3D (p < 0.0001); 54 months for LCK (p = 0.0009); 54.9 months for HLA-DRA (p = 0.0001); and 9 months for RAC2 mRNA expression (p = 0.0057). TGFB2 gene methylation drives TGFB2 mRNA expression to achieve clinical impact, as high levels of TGFB2 mRNA, at low levels of the marker genes, resulted in worse median OS times. TGFB2 methylation is a prognostic marker for PDAC patients within an immunosuppressed tumor microenvironment characterized by low CD8⁺ T-cell infiltration. This correlation is functionally associated with TGFB2 mRNA production, suggesting that targeting TGFB2 mRNA through knockdown can potentially enhance PDAC prognosis. Full article

Background: Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer with poor prognosis, and its progression is driven by epithelial plasticity and tumor microenvironment remodeling. Finding biomarkers that are responsible for the turning point from the early stage to the aggressive phase would facilitate clinical management. Method: In this study, we employed single-cell RNA sequencing to characterize a distinct subpopulation of highly proliferative epithelial cells undergoing a transitional phase during PDAC progression. By linking to cell cycle dysregulation, epithelial differentiation, and clinical staging, we constructed a gene-based risk score model using Lasso Cox regression. The expression of selected genes within the model was further validated using qPCR. Results: The model demonstrated robust predictive power for patient prognosis, TNM staging, and chemotherapy sensitivity. Further analysis of the tumor microenvironment revealed intensified crosstalk between a specific fibroblast subpopulation and transitional epithelial cells, mediated largely by collagen signaling. This stromal–epithelial interaction was found to contribute to the fibrotic barrier characteristic of PDAC. Additionally, immune profiling uncovered altered infiltration patterns, particularly involving natural killer (NK) cells in high-risk patients, suggesting mechanisms of immune tolerance and inhibition. Conclusions: These findings offer potential avenues for early detection, risk stratification, and targeted therapeutic strategies in PDAC. Full article

Background and Clinical Significance: Pancreatic cancer was the third leading cause of cancer-related mortality in the United States in 2020 after lung and colorectal cancers. The prevalence of pancreatic cancer has been increasing and is projected to continue rising through 2040, with an estimated 355,317 additional cases expected. We present the case of an 81-year-old patient with metastatic pancreatic ductal adenocarcinoma (PDAC) who tolerated NALIRIFOX for a year with grade 1 adverse events. Case presentation: An 81-year-old Asian male presented with abdominal pain associated with weight loss and fatigue. An abdominal computed tomography (CT) scan showed a mass in the body of the pancreas measuring 3.5 cm with an infiltrative appearance invading the retroperitoneum and encasing the splenic artery. A biopsy confirmed poorly differentiated PDAC. The patient received 13 cycles of NALIRIFOX in a palliative setting over the course of one year, demonstrating excellent tolerance aside from minor toxicities, including worsening of pre-existing macrocytic anemia, treatment-related grade 1 neuropathy, diarrhea, and thrombocytopenia. A subsequent CT scan revealed disease progression, and the patient was switched to second-line therapy. However, per his preference, the patient was referred to hospice care and passed away a few days later. Conclusions: This case highlights the excellent tolerability of NALIRIFOX in an elderly patient, with minimal adverse events observed, which is uncommon among similar patient populations. Full article

Background/Objectives: CAR T cell therapy, as a rapidly advancing immuno-oncology modality, has achieved significant success in the treatment of leukaemia and lymphoma. However, its application in solid tumours remains limited. The challenges include the heterogeneity of tumours, local immunosuppression, poor trafficking and infiltration, life-threatening toxicity and the lack of precise representative immunocompetent research models. Considering its typically dense and immunosuppressive tumour microenvironment (TME) and early metastasis, pancreatic ductal adenocarcinoma (PDAC) was employed as a model to address the challenges that hinder CAR T cell therapies against solid tumours and to expand immunotherapeutic options for advanced disease. Methods: A novel murine A20FMDV2 (A20) CAR T cell targeting integrin αvβ6 (mA20CART) was developed, demonstrating efficient and specific on-target cytotoxicity. The mA20CART cell as a monotherapy for orthotopic pancreatic cancer in an immunocompetent model demonstrated modest efficacy. Therefore, a novel triple therapy regimen, combining mA20CART cells with oncolytic vaccinia virus encoding IL-21 and a TGF-β-blocking antibody was evaluated in vivo. Results: The triple therapy improved overall survival, improved the safety profile of the CAR T cell therapy, attenuated metastasis and enhanced T cell infiltration. Notably, the potency of mA20CART was dependent on IL-2 supplementation. Conclusions: This study presents an αvβ6-targeting murine CAR T cell, offering a novel approach to developing CAR T cell technologies for solid tumours and a potential adjuvant therapy for pancreatic cancer. Full article

The high heterogeneity between patients can complicate the diagnosis and treatment of pancreatic ductal adenocarcinoma (PDAC). Here, we explored the association of universally differentially expressed genes (UDEGs) with resistance to chemotherapy and immunotherapy in the context of pancreatic cancer. In this work, sixteen up-regulated and three down-regulated genes that were dysregulated in more than 85% of 102 paired and 5% of 521 unpaired PDAC samples were identified and defined as UDEGs. A single-cell level analysis further validated the high expression levels of the up-UDEGs and the low levels of the down-UDEGs in cancer-related ductal cells, which could represent the malignant changes seen in pancreatic cancer. Based on a drug sensitivity analysis, we found that ANLN, GPRC5A and SERPINB5 are closely related to the resistance mechanism of PDAC, and their high expression predicted worse survival for PDAC patients. This suggests that targeting these genes could be a potential way to reduce drug resistance and improve survival. Based on the immune infiltration analysis, the abnormal expression of the UDEGs was found to be related to the formation of an immunosuppressive tumor microenvironment. In conclusion, these UDEGs are common features of PDAC and could be involved in the resistance of pancreatic cancer and might serve as novel drug targets to guide research into drug repurposing. Full article

Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer-related mortality in the United States, with poor overall survival across all stages. Less than 20% of patients are eligible for curative surgical resection at diagnosis, and despite adjuvant chemotherapy, most will experience disease recurrence within two years. The incorporation of immune-based strategies in the adjuvant setting remains an area of intense investigation with unrealized promise. It offers the potential of providing durable disease control for micro-metastatic disease following curative intent surgery and enabling personalized treatments based on mutational neoantigen profiles derived from resected specimens. However, most of these attempts have failed to demonstrate significant clinical success, likely due to the immunosuppressive tumor microenvironment (TME) and individual genetic heterogeneity. Despite these challenges, immune-based strategies, such as therapeutic vaccines targeted towards neoantigens, have demonstrated promise via immune activation and induction of T-cell tumor infiltration. In this review, we will highlight the foundational lessons learned from previous clinical trials of adjuvant immunotherapy, discussing the knowledge gained from analyses of trials with disappointing results. In addition, we will discuss how these data have been incorporated to design new agents and study concepts that are proving to be exciting in more recent trials, such as shared antigen vaccines and combination therapy with immune-checkpoint inhibitors and chemotherapy. This review will evaluate novel approaches in ongoing and future clinical studies and provide insight into how these immune-based strategies might evolve to address the unique challenges for treatment of PDAC in the adjuvant setting. Full article

Background/Objectives: Immunotherapy has shown promising results in some cancers, but its efficacy remains limited in pancreatic ductal adenocarcinoma (PDAC). Vaccines in nanoparticle form (nanovaccines) can incorporate immunostimulating components to induce a potent immune response. As mesothelin (MSLN) is a tumor-associated antigen overexpressed in PDAC, we evaluated the effect of MSLN nanovaccine in a syngeneic orthotopic KPC-PDAC mouse model. Methods: An MSLN peptide combining three MSLN epitopes and two adjuvants, poly I:C and R848, was encapsulated in PLGA–chitosan nanoparticles to generate the nanovaccine. Results: The MSLN nanovaccine was successfully taken up by dendritic cells in vitro and was found in inguinal lymph nodes 24 h after subcutaneous injection into C57BL/6 mice. Nanovaccine re-stimulation of splenocytes from vaccinated mice led to increased levels of interferon-γ in vitro compared to unstimulated splenocytes. Higher levels of MSLN-specific IgM and IgG antibodies were detected in the serum of vaccinated mice compared to that of control mice. Three vaccination regimens were tested: a prophylactic scheme that included vaccination before tumor induction and two therapeutic schemes involving early and late vaccination after tumor cell inoculation. MSLN nanovaccination inhibited KPC tumor progression and metastasis and induced higher CD8⁺ T cell infiltration in the tumor that developed in response to prophylactic and early therapeutic schedules but not in response to a later vaccination approach. Although the nanovaccine treatment elicited higher humoral and cellular antigen-specific responses in tumor-bearing mice for both vaccination strategies, the therapeutic vaccination also increased the expression of exhaustion markers in CD8⁺ T cells. Conclusions: Our results support the relevance of an MSLN-based nanovaccine as a new immunotherapy treatment for PDAC and propose an innovative method of vaccine delivery using NPs. Full article

Pancreatic cancer has the lowest 5-year survival rate (13%) among major cancers and is the third leading cause of cancer-related deaths in the United States. The high lethality of this cancer is attributed to its insidious onset, late-stage diagnosis, rapid progression, and limited treatment options. Addressing these challenges requires a deeper understanding of the complex tumor microenvironment to identify novel therapeutic targets. Newer approaches like adoptive cell therapy have shown remarkable success in treating hematological malignancies, but their application in solid tumors, particularly pancreatic cancer, is still in the early stages of development. ACT broadly involves isolating immune cells (T lymphocytes, Natural Killer cells, and macrophages) from the patient, followed by genetic engineering to enhance and mount a specific anti-tumor response. Various ACT modalities are under investigation for pancreatic cancer, including chimeric antigen receptor T cells (CAR-T), chimeric antigen receptor NK cells (CAR-NK), tumor-infiltrating lymphocytes (TIL), T-cell receptor (TCR)-engineered T cells, and cytokine-induced killer cells (CIK). Major hurdles have been identifying actionable tumor antigens and delivering focused cellular therapies to overcome the immunosuppressive and dense fibrotic stroma surrounding the pancreatic cancer. Further studies are needed to explore the limitations faced by cellular therapy in pancreatic cancer and identify novel combination treatment approaches in order to improve clinical outcomes. Full article

Background/Objectives: Pancreatic ductal adenocarcinoma (PDA) is one of the most malignant solid cancers. KRAS mutation accounts for over 90% of cases. p21-activated kinases (PAKs) act downstream of KRAS and are involved in tumorigenesis. The inhibition of PAK4 suppresses PDA by stimulating the tumor infiltration of cytotoxic T cells. The major histocompatibility complex class I (MHC I) is a key in presenting antigens to cytotoxic T cells. MHC I degradation via autophagy promotes the immune evasion of pancreatic cancer. We investigated the effect of PAK4 inhibition on MHC I expression and autophagy. Methods: In this study, using proteomic analysis, fluorescence-activated cell sorting (FACS), and immunoblotting, we examined the effect of PAK4 knockout (KO) in human PDA cells on the expression of MHC I and autophagy to identify the mechanism involved in the stimulation of cytotoxic T cells by PAK4 inhibition. Results: We found that PAK4 KO increased MHC I expression in two human PDA cell lines: MiaPaCa-2 and PANC-1. PAK4 KO also increased cancer cell autophagy. However, the inhibition of autophagy by chloroquine (CQ) did not affect the effect of PAK4 KO on apoptosis and cell death. More importantly, the inhibition of autophagy by CQ did not alter the expression of MHC I stimulated by PAK4 KO, indicating that PAK4 KO stimulated MHC I expression via an autophagy-independent pathway. Conclusions: We identified a role of PAK4 in MHC I expression by PDA cells, which is independent of autophagy. Full article

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with poor outcomes due to frequent recurrence, metastasis, and resistance to treatment. A major contributor to this resistance is the tumor’s ability to suppress natural killer (NK) cells, which are key players in the immune system’s fight against cancer. In PDAC, the tumor microenvironment (TME) creates conditions that impair NK cell function, including reduced proliferation, weakened cytotoxicity, and limited tumor infiltration. This review examines how interactions between tumor-derived factors, NK cells, and the TME contribute to tumor progression and treatment resistance. To address these challenges, we propose a new “Triple NK Cell Biomarker Approach”. This strategy focuses on identifying biomarkers from three critical areas: tumor characteristics, TME factors, and NK cell suppression mechanisms. This approach could guide personalized treatments to enhance NK cell activity. Additionally, we highlight the potential of combining NK cell-based therapies with conventional treatments and repurposed drugs to improve outcomes for PDAC patients. While progress has been made, more research is needed to better understand NK cell dysfunction and develop effective therapies to overcome these barriers. Full article

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with limited effective therapeutic options. Due to a variety of cancer cell-intrinsic factors, including KRAS mutations, chemokine production, and other mechanisms that elicit a dysregulated host immune response, PDAC is often characterized by poor immune infiltration and an immune-privileged fibrotic stroma. As understanding of the tumor microenvironment (TME) evolves, novel therapies are being developed to target immunosuppressive mechanisms. Immune checkpoint inhibitors have limited efficacy when used alone or with radiation. Combinations of immune therapies, along with chemotherapy or chemoradiation, have demonstrated promise in preclinical and early clinical trials. Despite dismal response rates for immunotherapy for metastatic PDAC, response rates with neoadjuvant immunotherapy are somewhat encouraging, suggesting that incorporation of immunotherapy in the treatment of PDAC should be earlier in the disease course. Precision therapy for PDAC may be informed by advances in transcriptomic sequencing that can identify immunophenotypes, allowing for more appropriate treatment selection for each individual patient. Personalized and antigen-specific therapies are an increasing topic of interest, including adjuvant immunotherapy using personalized mRNA vaccines to prevent recurrence. Further development of personalized immune therapies will need to balance precision with generalizability and cost. Full article

Associations between inflammation and cancer were first discovered approximately 160 years ago by Rudolf Virchow, who observed that tumors were infiltrated with inflammatory cells, and defined inflammation as a pathological condition. Inflammation has now emerged as one of the key mediators in oncogenesis and tumor progression, including pancreatic ductal adenocarcinoma (PDAC). However, the role of inflammatory processes in cancers is complicated and controversial, and the detailed regulatory mechanisms are still unclear. This review elucidates the dynamic interplay between inflammation and immune regulation, microenvironment alteration, metabolic reprogramming, and microbiome risk factors in PDAC, committing to exploring a deeper understanding of the role of crucial inflammatory pathways and molecules for providing insights into therapeutic strategies. Full article

Pancreatic cancer comprises different subtypes, where most cases include ductal adenocarcinoma (PDAC). It is one of the deadliest tumor types, with a poor prognosis. In the majority of patients, the disease has already spread by the time of diagnosis, making full recovery unlikely and increasing mortality risk. Despite developments in its detection and management, including chemotherapy, radiotherapy, and targeted therapies as well as advances in immunotherapy, only in about 13% of PDAC patients does the overall survival exceed 5 years. This may be attributed, at least in part, to the highly desmoplastic tumor microenvironment (TME) that acts as a barrier limiting perfusion, drug delivery, and immune cell infiltration and contributes to the establishment of immunologically ‘cold’ conditions. Therefore, there is an urgent need to unravel the complexity of the TME that promotes PDAC progression and decipher the mechanisms of pancreatic tumors’ resistance to immunotherapy. In this review, we provide an overview of the major cellular and non-cellular components of PDAC TME, as well as their biological interplays. We also discuss the current state of PDAC therapeutic treatments and focus on ongoing and future immunotherapy efforts and multimodal treatments aiming at remodeling the TME to improve therapeutic efficacy. Full article