Search Results (2,065)

Background/Objectives: Despite the clinical success of immune checkpoint blockade (ICB), its efficacy remains limited in immunologically “cold” tumors, primarily due to poor immunogenicity and an immunosuppressive tumor microenvironment (TME). Chemo-immunotherapy offers a potential strategy to enhance ICB response, yet its application is often hindered by inadequate tumor-targeted delivery and systemic immunosuppressive side effects. Biomimetic nanotechnology represents a promising approach to overcoming these limitations by improving drug delivery and facilitating effective combination regimens. Methods: We developed a biomimetic nanosystem (NVs@DOX) through genetic engineering of cellular membranes and optimized nanoformulation techniques, enabling co-delivery of doxorubicin (DOX) and ICB agents. This design aims to maximize synergistic antitumor effects while minimizing adverse impacts. Results: In vitro studies demonstrated the potent cytotoxicity of NVs@DOX, including significant inhibition of cancer cell proliferation and complete suppression of colony formation. In a 4T1 murine breast cancer model, NVs@DOX treatment led to substantial tumor growth inhibition (approximately 72%) without notable body weight loss, underscoring a favorable safety profile alongside enhanced therapeutic efficacy. Conclusions: The NVs@DOX platform effectively integrates doxorubicin with ICB within a biomimetic nanocarrier, significantly improving chemo-immunotherapy outcomes. This strategy highlights the potential of genetically engineered cellular nanoparticles as a promising combinatorial approach for the treatment of breast cancer. Full article

Background/Objectives: Breast cancer cells rely on both mitochondrial metabolism and proteostatic mechanisms for cell fitness. The mitochondrial enzyme IDH2 supports redox balance and biosynthesis, while the ubiquitin-proteasome system (UPS) preserves protein quality. This study aimed to determine whether inhibiting IDH2 enhances sensitivity to proteasome-targeting agents across breast cancer subtypes. Methods: A panel of human and murine breast cancer cell lines was treated with the IDH2 inhibitor AGI-6780, alone or in combination with the proteasome inhibitor carfilzomib (CFZ) or the E1 ubiquitin-activating enzyme inhibitor TAK-243. Synergy was evaluated using Bliss scoring. Apoptosis, clonogenicity, and pathway modulation were assessed through Western blotting, colony-formation assays, and reverse-phase protein array (RPPA) profiling. Results: We observed that co-targeting IDH2 and the UPS produced strong synergistic cytotoxicity in multiple breast cancer models, including in triple-negative MDA-MB-231 and 4T1 cells (Bliss > 25). Combination treatments led to pronounced apoptosis, evidenced by cleaved PARP-1 and Caspase-3 cleavage, and a marked loss of clonogenic potential. RPPA analysis revealed significant alterations in key survival and stress-response pathways, including NF-κB, PI3K-p85, Src, and p38-MAPK. Conclusions: Inhibition of IDH2 markedly enhances the cytotoxic effects of proteasome-targeting by disrupting metabolic–proteostatic balance and promoting apoptotic cell death. These findings identify a growth-inhibitory effect that may be leveraged to improve functional dependency in breast cancer, particularly in triple-negative breast cancer, which currently lacks efficient drug treatments. Full article

Background: Triple-negative breast cancers (TNBCs) are among the most aggressive breast tumors, due not only to the absence of clinically functional biomarkers used in other molecular subtypes, but also their marked heterogeneity and pronounced migratory and invasive behavior. The search for new molecules of interest for risk prediction, diagnosis and therapy stems from the class of long non-coding RNAs (lncRNAs), which often display context-dependent (“dual”) functions and tissue specificity. Among them, lncRNA LINC01133 stands out for its dysregulation across cancer, although its molecular role in TNBC remains unclear. Methods: In the present study, we used the human TNBC cell line Hs578T to generate a cell panel comprising the parental line (Hs578T_wt), the control line (Hs578T_ctr), and the LINC01133 knockout line (Hs578T_ko). Subsequently, we performed bulk RNA-Seq to identify KO-associated Differentially Expressed Genes (DEGs) using ko_vs_ctr as the primary contrast. Functional interpretation was achieved by Over-Representation Analysis (ORA) using Gene Ontology. We then conducted a comparative patient-cohort analysis using TCGA-BRCA Basal-like/TNBC cases (TCGA/BRCA n = 1098; Basal-like/TNBC n = 199), classified with the AIMS algorithm, and evaluated concordance between KO-associated signatures and patient tumor expression patterns via trend-based analyses across the LINC01133 expression levels and associated genes. Results: A total of 265 KO-dominant DEGs were identified in Hs578T_ko, reflecting transcriptional changes consistent with tumor progression, with enrichment of pathways associated with LINC01133 knockout including cell adhesion, cell–cell interactions, epithelial–mesenchymal transition (EMT), and extracellular matrix (ECM) remodeling. The main DEGs included ITIH5, GLUL, CACNB2, PDX1, ASPN, PTGER3, MFAP4, PI15, EPHB6, and CPA3 with additional candidates, such as KAZN and the lncRNA gene SSC4D, which have been implicated in migration/invasion, ECM remodeling, or signaling across multiple tumor contexts. Translational analyses in TCGA-BRCA basal-like tumors suggested a descriptive association in which lower LINC01133 levels were accompanied by shifts in the expression trends of genes linked to ECM/EMT programs and modulation of genes related to cell adhesion and protease inhibition. Conclusions: These results suggest a transcriptional model in which LINC01133 is associated with TNBC-related gene expression programs in a concentration-dependent manner, with loss of LINC01133 being associated with a transcriptomic shift toward pro-migratory/ECM remodeling signatures. While functional validation is required to establish causality, these data support LINC01133 as a molecule of interest in breast cancer research. Full article

Background/Objectives: Triple negative breast cancer (TNBC) is an aggressive subtype treated primarily with chemotherapy, which often leads to drug resistance (DR) and reduced effectiveness. Phytochemicals, including anthocyanins from dark sweet cherry (ACN), have emerged as potential adjuvants to overcome DR, though mechanisms remain unclear. This study examines ACN effects on canonical and non-canonical antioxidant pathways (Nrf2-Keap1 and p62) as a mechanism to overcome DR in 4T1 TNBC cells with acquired DR. Methods: Two conditions were tested: ACN with basal doxorubicin (DOX) as resistance-maintaining conditions and ACN with DOX at IC₅₀ to induce oxidative stress (OS). Results: Under resistance-maintaining conditions, ACNs activated the canonical Nrf2-Keap1 pathway at high doses, which can potentially contribute to DR development due to its cellular protection effects. However, at a low dose, ACN did not trigger an antioxidant response linked to GST and GGT enzyme activities and instead impaired autophagy, increasing OS. Under OS, ACN activated the non-canonical antioxidant pathway mediated by p62 while deactivating Nrf2, leading to autophagy-induced cell death and further impairing autophagy at a low dose. Notably, inflammation persisted at both treatment levels without being relieved, keeping stress signaling active. At both conditions, ACN at doses likely attainable under physiological conditions effectively impaired autophagy and elevated OS, resulting in cell death. Conclusions: These results underscore the context-dependent dual function of polyphenols in cancer therapy, demonstrating their potential to enhance cellular sensitivity to chemotherapy and providing guidance for their strategic use as adjuvants in treating TNBC and overcoming DR. However, this study was limited to a single cell line derived from a murine model. Future research should include comparative studies using human TNBC cell lines to validate these findings and better assess their translational relevance. Full article

Background: Triple-negative breast cancer (TNBC) represents the most aggressive breast cancer subtype, characterized by high genomic instability, metabolic stress, and limited therapeutic options. Ferroptosis, an iron-dependent form of regulated cell death, has emerged as a promising vulnerability in TNBC, yet its subtype-specific regulatory landscape remains insufficiently defined. Methods: Using transcriptomic (METABRIC, TCGA, GEO) and proteomic (CPTAC) datasets, ferroptosis-related genes were profiled across PAM50 breast cancer subtypes. Differential expression, univariate Cox regression, LASSO modeling, survival analyses, GSEA, and dimensionality reduction (PCA, t-SNE) were applied. A Ferroptosis Index (FI) was calculated using β-coefficients from the Cox/LASSO regression model. Single-cell RNA-seq data was used to map ferroptosis-associated signature across tumor and microenvironmental compartments. Results: Basal-like tumors exhibited the strongest ferroptosis-associated transcriptional shift, characterized by upregulation of ACSL4 and EZH2 and downregulation of AR, GPX4, and CIRBP. Sixteen ferroptosis-related genes were associated with overall survival, forming a ferroptosis-associated signature. The FI was significantly higher in Basal-like tumors, indicating elevated ferroptosis-associated transcriptional state. GSEA revealed enrichment of cell cycle, mitotic, cytoskeletal, and metabolic stress pathways. Single-cell analysis demonstrated expression of ferroptosis markers across cancer epithelial, stromal, and myeloid populations. Conclusions: Basal-like tumors harbor a distinct ferroptosis-associated transcriptional state linked to tumor aggressiveness and poor prognosis. These findings provide a biologically grounded framework for ferroptosis-related stratification and support future functional and translational studies targeting ferroptosis vulnerabilities in aggressive breast cancer. Full article

Introduction: The addition of immunotherapy to neoadjuvant treatment for early triple-negative breast cancer (TNBC) has been adopted in clinical practice in France since March 2022, with little real-world data published on the topic. The aim of this study was to evaluate real-world data on treatment feasibility, efficacy, and related toxicities, with a specific focus on immune-related adverse events (irAEs). Methods: We conducted a retrospective analysis of patients who completed at least the neoadjuvant sequence of pembrolizumab combined with chemotherapy for early-stage TNBC at Montpellier Cancer Institute from April 2022 to July 2024. Adverse events were graded according to the Common Terminology Criteria for Adverse Events (CTCAE) v5.0. The pathological complete response (pCR) was defined as the absence of residual invasive disease in the breast and axillary lymph nodes (ypT0/Tis ypN0). Results: We reviewed data from 92 patient records. The median age at diagnosis was 50 years (range: 27–76). The history of autoimmune disease was noted in 3.2% of patients. Grade 3–4 irAEs were observed in 20% of patients and included hepatitis (8.6%), colitis (3.3%), skin toxicity (2.1%), myocarditis (2%), arthralgia (1%), autoimmune hemolytic anemia (1%), hypothyroidism (1%), and adrenal insufficiency (1%). No treatment-related deaths were reported. Immunotherapy was discontinued due to irAEs in 29.3% of patients in the study population. The pCR rate was 61,1%, with no significant association between the number of neoadjuvant pembrolizumab cycles and the pCR rate (p = 0.7). Patients experiencing grade 3–4 irAEs had a pCR rate of 80%, compared to 56.7% in those without such toxicities (p = 0.079). Initial positivity of antinuclear antibodies (ANA) was not associated with an increased incidence of irAEs. Conclusions: The immune-related adverse events and efficacy data observed in our cohort were broadly comparable to those reported in the KEYNOTE-522 trial, with no treatment-related deaths. Patients with grade 3–4 irAEs tended to have higher pCR rates. Full article

Heterocyclic compounds have enormous pharmacological potential and therefore play a key role in the design of new drugs. Dipyridothiazines, both heterocyclic compounds and phenothiazine derivatives, exhibit promising anticancer, immunostimulatory, and antioxidant activities. The aim of this study was to design, synthesize, and evaluate the cytotoxicity of new 10-heteroaryl dipyridothiazines based on 2,7- and 3,6-diazaphenothiazine cores. The structural characterization of the new compounds was confirmed by spectroscopic methods. Cytotoxicity analysis was performed using the MTT assay against human keratinocytes (HaCaT) and two types of cancer cell lines: breast cancer (MDA-MB-231), lung carcer (A-549). The reference drugs used in the study were doxorubicin and cisplatin. The group of derivatives studied included active compounds as well as inactive derivatives. In order to explain differences in an activity level, molecular modelling supported by molecular dynamics was performed on histone deacetylase 6 (HDAC6), a known therapeutic target associated with oncogenic transformation and cancer metastasis. Molecular docking indicated that the derivative formed on the 2,7-diazaphenothiazine core is a more potent HDAC6 inhibitor, characterized by more stable binding and more favourable complex energy, despite minimal structural differences compared to the compound formed on the 3,6-diazaphenothiazine core. A preliminary SAR analysis was performed. Full article

Breast cancer remains one of the leading causes of cancer-related mortality among women worldwide. Although cisplatin is widely used in chemotherapy, its clinical efficacy is often limited by adverse effects and resistance. Thus, natural bioactive compounds are gaining attention as complementary therapeutic agents. This study aimed to evaluate the anti-tumor effects of Annona muricata leaf extract on murine breast cancer 4T1 cells, used alone or in combination with cisplatin. Cisplatin induced intrinsic apoptosis through mitochondrial membrane disruption, up-regulation of the Bax gene and inhibition of the PI3K/AKT/mTOR signaling pathway. Cisplatin also promoted hypoxia by HIF1α gene expression, inflammation by TNFα and IL-6 gene expression, and induced cell cycle arrest at the sub-G1 phase by down-regulation of cyclin D1 and cyclin E1 genes. Annona muricata leaf extract triggered autophagy-mediated 4T1 cell death through mainly mTOR down-regulation and increased expression of Beclin1 and LC3 genes. It also induced cell cycle arrest at sub-G1 and S phases in a concentration- and time-dependent manner. When, combined with cisplatin, Annona muricata extract shifts the cell death pathway from intrinsic apoptosis toward autophagy by reduced caspase-3 gene expression and activity and enhanced LC3-I to LC3-II conversion. Moreover, Annona muricata extract attenuated cisplatin-induced inflammation by inhibiting TNFα and IL-6 gene expression and reinforced cell cycle arrest through suppression of the cyclin D1 gene. In conclusion, our results suggest that Annona muricata leaf extract exerts significant anti-tumor activity in breast cancer cells and may enhance cisplatin efficacy by shifting the signaling pathway from intrinsic apoptosis toward autophagy, and attenuating inflammation-related effects, supporting its potential use as a complementary therapeutic strategy. Full article

Adipose tissue plays a crucial role in breast cancer (BC) progression by actively modulating the tumor microenvironment. We investigated how tumor proximity modifies adipose tissue by analyzing selected adipose-related and prognosis-associated markers in explants from BC patients and healthy donors. Explants were categorized by proximity to the tumor as adjacent (less than 2 cm), distant (over 2 cm), alongside normal explants (controls). FABP4 and vimentin expression was increased in proximity to the tumor, while caveolin-1, CD44, MMP9, and adiponectin showed minimal or no changes. Conditioned media (CM) from adjacent and normal explants were then assessed for their effects on tumorigenic traits in hormone-receptor-positive breast cancer (HR+ BC) and triple-negative breast cancer (TNBC) cell lines. Adjacent-CM enhanced migration, induced cytoskeletal remodeling, reduced adhesion, and promoted an elongated, motile phenotype in T47D cells. Poor-prognosis markers (caveolin-1, vimentin, CD44) were upregulated in at least one HR+ BC model, whereas Nanog and KLF4 showed modest variation. In TNBC cells, both normal- and adjacent-CM partially shifted MDA-MB-231 morphology toward a more epithelial-like state, decreasing caveolin-1 levels, while adjacent-CM increased MMP9 expression. Overall, these results reveal that adipose tissue-derived soluble factors exert significant and subtype-dependent effects on BC tumorigenicity. Full article

Background/Objectives: Male breast cancer (MBC) is rare, accounting for less than 1% of all breast cancers. Given its low incidence, male breast cancer (MBC) remains understudied; this 33-year Serbian cohort was assessed for clinicopathological features, therapeutic approaches, genetic alterations, and survival. Methods: We retrospectively analyzed MBC patients diagnosed between 1991 and 2024 at the Institute for Oncology and Radiology of Serbia. Data included demographics, tumor characteristics, and stage, treatment, hormone receptor and HER2 status, Ki-67 index, genetic testing, and survival. Results: A total of 191 patients were identified (median age 66). Family history was negative in 91% and positive in 5.8%. T2 tumors were most frequent (36%), and 96% presented without metastasis. Mastectomy with axillary or sentinel lymph node dissection was performed in 78.5%. Neoadjuvant chemotherapy and radiotherapy were administered in 5.8% and 8.4%. Estrogen receptor positivity was 72%, progesterone receptor 88%, HER2 overexpression 11.0%, and triple-negative tumors 2.6% (40% with axillary involvement). High Ki-67 (≥15%) was recorded in 28.8%. Adjuvant chemotherapy, radiotherapy, and hormone therapy were given in 36%, 58%, and 68%. Among 37 genetically tested patients, seven had pathogenic variants (BRCA1, BRCA2, CHEK2, PALB2). Disease recurrence occurred in 30%. Median follow-up was 53 months. Median disease-free survival (DFS) was 82 months (1-, 2-, 5-, 10-year DFS: 87%, 73%, 57%, 39%). Median overall survival (OS) 131 months (1-, 2-, 5-, 10-year OS: 95%, 93%, 73%, 53%). Conclusions: This long-term cohort highlights the predominance of hormone-receptor positivity, the infrequency of germline mutations, and moderate survival rates, informing patient management and guiding future studies. Full article

Five rare variants in BRIP1/FANCJ, initially identified in ovarian cancer (OC) or breast cancer (BC) cases by the adult hereditary cancer clinics, were investigated for their candidacy as clinically relevant variants. These variants were investigated genetically in a population exhibiting genetic drift and molecularly assayed for biological impact. Using in silico tools, population-based genetic databases and other resources, three of the five reported BRIP1 variants were likely to be damaging: c.797C>T; p.Thr266Met, c.2087C>T; p.Pro696Leu and c.2990_2993delCAAA; p.Thr997ArgfsTer61. The carrier frequencies ranged from 0 to 0.7% in ancestry-defined cancer groups comprising 47 OC families, 49 hereditary breast and ovarian cancer syndrome families, 142 hereditary breast cancer syndrome families, 435 sporadic OC cases and 563 sporadic BC cases and 0–0.2% in 1025 population-matched controls. Multiple carriers of the these variants were identified in additional population-matched cancer cases. Of the five reported BRIP1 variants, p.Thr266Met, p.Pro696Leu and c.2990_2993delCAAA; p.Thr997ArgfsTer61, which were predicted to be damaging, conferred cellular sensitivity to mitomycin C and cisplatin unlike p.Ser139Ala and p.Ala406Ser. Collectively, our investigation implicates BRIP1 c.797C>T; p.Thr266Met, c.2087C>T; p.Pro696Leu and c.2990_2993delCAAA; p.Thr997ArgfsTer61 as deleterious variants in OC and BC. Full article

Background and Objectives: Sentinel lymph node (LN) biopsy (SLNB) remains to be the standard approach for surgical axillary staging of breast cancer (BC) patients. The aim of this study was to investigate the factors that affect axillary LN involvement in early BC patients. Materials and Methods: Clinically node negative early stage (cT1-2N0) BC patients having undergone breast conserving surgery (BCS) between February 2021 and January 2024 were included. During axillary exploration of all cases, sentinel LNs were excised and reserved for permanent section pathological examination (PS) only. Historical records of patients including clinicopathological features, surgical outcomes as well as pathological results were recorded and analyzed retrospectively. p < 0.05 indicated statistically significant results. Results: The study group consisted of 150 women with cT1-2N0 BC having undergone BCS with a median age of 59 (range: 25–81) years. According to the PS results of the sentinel LNs, the need for reoperation to complete axillary lymph node dissection was present in three (2%) patients. Tumors of the Luminal B subtype were significantly associated with increased sentinel LN positivity (p = 0.014). The risk of sentinel LN metastasis was found to be 5.2 times greater in patients with a Ki-67 ≥ %14 [OR: 5.224 (%95 CI:1.73–15.82, p = 0.003)] and the Ki-67 proliferation index was determined as an independent risk factor. Conclusions: In early-stage BC patients, PS of the excised sentinel LN offers sufficient axillary LN staging. On the other hand, a more careful clinical assessment is necessary for early BC patients harboring tumors with an elevated Ki-67 index and/or tumors of the Luminal B subtype. Full article

Objectives: The molecular characterization of male breast cancer (MaBC) has long been understudied, primarily due to its rare occurrence. Clinical management of MaBC remains profoundly challenging, with current therapeutic strategies largely extrapolated from female breast cancer protocols. Methods: Through panel-based sequencing targeting BRCA1, BRCA2, and PALB2 variants, we delineated the genomic landscape of 96 MaBC cases. Subsequent whole-exome sequencing (WES) of 84 BRCA1/2- and PALB2-mutation-negative MaBC patients, compared against 4480 healthy controls, revealed compelling findings. Results: Pathogenic variants in BRCA1/2 and PALB2 were identified in 14.6% (14/96) of MaBC cases, with BRCA2 mutations predominating at 12.5% (n = 12). Notably, one patient harbored the BRCA1 c.4015G > T stop-gained mutation, while another exhibited the PALB2 c.481_482dupGA alteration. Our analysis further uncovered 170 pathogenic/likely pathogenic mutations, with RAD50, DMD, ARSA, and ABCC6 demonstrating recurrent mutations in MaBC. Conclusions: As the inaugural germline genomic investigation of MaBC in a Han Chinese population, this work reveals clinically actionable alterations with diagnostic and therapeutic implications. These discoveries not only advance our understanding of MaBC’s molecular architecture but also underscore the critical need for dedicated research into this malignancy. Full article

Breast cancer is a significant cause of death worldwide. Recent research has focused on identifying natural compounds for developing effective cancer treatments. Resiniferatoxin, a transient receptor potential vanilloid 1 (TRPV1) agonist, is a common diterpene in Euphorbia bicolor Engelm. & A. Gray (Euphorbiaceae), a plant native to the southern United States that has not been studied before. We investigated the antiproliferative activities and mechanisms of action of E. bicolor xylene extract in estrogen receptor-positive T47D and triple-negative MDA-MB-231 cell lines. The extract significantly reduced the viability of T47D and MDA-MB-231 cells in a dose-dependent manner. In MDA-MB-231 cells, the extract induced apoptosis via intracellular calcium overload, triggered by TRPV1 activation. This effect was diminished by the TRPV1 antagonist capsazepine and the calcium chelator BAPTA-AM. Intracellular calcium influx was confirmed through Fura-2 AM staining, revealing that E. bicolor phytochemicals activated TRPV1 in MDA-MB-231 cells. Treatment of T47D cells with E. bicolor xylene extract resulted in apoptosis associated with reactive oxygen species (ROS) generation (10-fold higher in T47D cells than in MDA-MB-231 cells) and mitochondrial calcium overload. These effects were significantly blocked when cells were pretreated with N-acetyl-l-cysteine (NAC), a ROS inhibitor. Both cell lines underwent apoptosis via multiple mitochondrial- and endoplasmic reticulum stress–mediated pathways. This was supported by the activation of caspases 3, 8, and 9; increased expression of FAS, XBP1s, and CHOP; upregulation of BAX; and downregulation of BCL-2. In addition, PI3K, AKT, and pAKT protein expressions were also reduced in both cell lines, indicating downregulation of PI3K/Akt signaling pathway. Phytochemicals in E. bicolor xylene extract could become promising ingredients for developing breast cancer therapeutics. Full article

Chimeric antigen receptor (CAR) T cell therapy has demonstrated clinical success in hematologic malignancies but has limited efficacy in solid tumors due to tumor microenvironment (TME) barriers that impede CAR T cell recognition, infiltration, and sustained function. Traditional 2D assays inadequately recapitulate these constraints, necessitating improved in vitro models. This study validated a 3D tumor spheroid platform using an agarose microwell system to generate uniform B7-H3-positive spheroids from multiple solid tumor cell lines, enabling the evaluation of CAR T cell activity. TME-relevant immune modulation under 3D conditions was analyzed by flow cytometry for B7-H3, MHC I/II, and antigen processing machinery (APM), followed by co-culture with B7-H3 CAR T cells to assess cytotoxicity, spheroid integrity, tumor viability, and CAR T cell activation, exhaustion, and cytokine production. Two human cancer-cell-line-derived spheroids, DU 145 (prostate cancer) and SUM159 (breast cancer), retained B7-H3 expression, while MC38 (mouse colon cancer)-derived spheroids served as a B7-H3 negative control. Under 3D culture conditions, DU 145 and SUM159 spheroids acquire TME-like immune evasion characteristics and specifically downregulated MHC-I and APM (TAP1, TAP2, LMP7) with concurrent upregulation of MHC-II and calreticulin. Co-culture showed effective spheroid infiltration, cytotoxicity, and structural disruption, with infiltrating CAR T cells displaying higher CD4⁺ fraction, activation, exhaustion, effector/terminal differentiation, and IFN-γ/TNF-α production. This 3D platform recapitulates critical TME constraints and provides a cost-effective, feasible preclinical tool to assess CAR T therapies beyond conventional 2D assays. Full article