Search Results (1,678)

Poly(ADP-ribose) polymerase inhibitors (PARPi) have reshaped therapy for advanced prostate cancer, yet durable benefit remains concentrated in BRCA1/2-altered tumors, especially BRCA2, and most responders eventually relapse. Here, we frame PARPi response and resistance through a unifying model in which DNA damage response (DDR) rewiring (e.g., homologous recombination repair (HRR) restoration, fork protection, checkpoint tolerance, and altered drug handling) converges with treatment-induced dormancy and quiescent therapy-tolerant residual states that sustain minimal residual disease (MRD) under androgen receptor pathway inhibition (ARPI) and PARP blockade. We synthesize clinical and translational evidence for PARPi monotherapy and PARPi-based combinations across disease states. In first-line metastatic castration-resistant prostate cancer (mCRPC), PARPi plus ARPI consistently prolongs radiographic progression-free survival, with the greatest benefit in HRR-altered tumors, and emerging overall-survival signals in selected subgroups. In later-line settings, monotherapy activity is most robust in BRCA2-mutated disease, whereas non-BRCA HRR alterations show heterogeneous and often modest responses, underscoring the need for biomarkers beyond gene panels. We also discuss combination strategies with DDR-targeting agents, radioligand therapies, and immunotherapy, and summarize ongoing phase III programs in metastatic castration-sensitive prostate cancer (mCSPC). Finally, we outline practical considerations for biomarker-informed patient selection, monitoring, sequencing, and toxicity management, with particular emphasis on intercepting MRD and resistance evolution. Full article

Hereditary cancer syndromes (HCSs), including BRCA 1/2-associated hereditary breast and ovarian cancer (HBOC) and Lynch syndrome (LS), confer substantial lifetime cancer risks, yet adherence to recommended risk-management strategies remains variable. This population-based retrospective cohort study examined cancer prevention practices, outcomes, and predictors of cancer occurrence among 476 BRCA and LS carriers identified through the Provincial Medical Genetics Program in Newfoundland and Labrador, Canada (2001–2022). Linked genetic, surgical, screening, and cancer registry data were evaluated, with adherence assessed during two intervals (2018–2020 and 2020–2022) based on NCCN guidelines. Participants were predominantly female (69%), with a mean age of 48.5 years at genetic testing; nearly 70% of primary cancers were already diagnosed at the time of testing. BRCA carriers demonstrated higher uptake of breast MRI (58–61%) and risk-reducing salpingo-oophorectomy (63–66%) compared with LS carriers’ colonoscopy uptake (42–44%). In univariate analyses, non-adherence during 2018–2020 was associated with increased odds of cancer after testing (OR ≈ 4.43, p < 0.001); this remained significant in the multivariate model (OR = 8.70; p = 0.0004). Individuals who did not follow recommended risk-management guidelines had nearly nine times greater odds of developing cancer after genetic testing than those who fully adhered to guidelines. Older age at referral (OR = 1.07/year, p < 0.001) also increased the odds of developing cancer. Study findings indicate that late referral and pre-existing cancers diminish the preventive impact of guideline-based risk management. System-level initiatives to promote earlier genetic testing, enhance cascade outreach, and strengthen surveillance pathways are needed to optimize cancer prevention and earlier cancer detection in high-risk populations. Full article

Upstream binding transcription factor (UBTF) is a nuclear transcription factor implicated in ribosome biogenesis, yet its pancancer relevance and immunological associations remain incompletely understood. We integrated datasets from The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), Human Protein Atlas (HPA), Cancer Cell Line Encyclopedia (CCLE), and cBioPortal databases to characterize UBTF expression, genomic alterations, and prognostic value across 33 cancer types. Immune microenvironment analyses were performed using ESTIMATE and multiple deconvolution algorithms. CRISPR-Cas9–mediated UBTF depletion was conducted in breast invasive carcinoma (BRCA) cell lines to evaluate functional roles. UBTF was broadly upregulated in multiple tumors with recurrent copy number gains. Survival analyses revealed cancer type–dependent prognostic associations. UBTF expression correlated with immune/stromal contexture, checkpoint features, and predicted immunotherapy response. In BRCA, UBTF depletion reduced proliferation and migration while increasing apoptosis. A UBTF-related prognostic signature effectively stratified patient outcomes and was associated with immune infiltration and predicted immunotherapy response. UBTF represents a pancancer biomarker linked to tumor immunity, with validated functional significance in BRCA and potential utility for risk stratification. Full article

Background/Objectives: Decision making for contralateral prophylactic mastectomy in patients with breast cancer involves complex risk–benefit trade-offs that may lead to decisional conflict. Understanding factors associated with decisional conflict, particularly for patients with pathogenic variants in BRCA genes, is critical for developing tailored decisional support. This study examined decisional conflict, shared decision making, and decisional role preferences in Korean patients with breast cancer considering contralateral prophylactic mastectomy, focusing on factors associated with clinically significant decisional conflict and differences by BRCA status. Methods: A cross-sectional, internet-based survey was conducted between August and October 2024. Independent t-tests, univariate, and multivariate logistic regression analyses identified factors associated with clinically significant decisional conflict. Results: The sample included 167 Korean patients with breast cancer (90 BRCA carriers and 77 non-carriers). Most patients (76%) experienced clinically significant decisional conflict. Non-carriers reported higher decisional conflict (44.2 vs. 29.3, p < 0.001) and lower shared decision making than BRCA carriers (44.6 vs. 61.9, p < 0.001). Role preferences were similarly distributed across groups (50.3% active, 24.0% collaborative, 25.7% passive). In multivariable analysis, clinically significant decisional conflict in the total sample was associated with non-carrier status (OR = 2.98) and lower shared decision-making scores (OR = 0.94) (p < 0.05), explaining 28% of the variance. Among BRCA carriers, clinically significant decisional conflict was associated with lower shared decision-making scores (OR = 0.92) and passive role preferences (vs. active) (OR = 4.88). No variables were significantly associated with decisional conflict among non-carriers. Conclusions: Findings suggest that decisional conflict is influenced by genetic risk and the quality of the decision-making process. Improving patient engagement by identifying preferred decisional roles, understanding the reasons behind these preferences, and encouraging shared decision making may help reduce decisional conflict, particularly among BRCA carriers. Further research is needed to better understand factors associated with decisional conflict among non-carriers. Full article

Background: Urothelial bladder cancer (UBC) is a molecularly heterogeneous disease, and most sequencing studies have relied on bladder-specific or solid tumor-restricted panels. Whether broader pan-cancer assays provide additional clinically relevant information remains unclear. Methods: We performed targeted next-generation sequencing using an extended gene panel on tumor samples from 100 patients with UBC treated at a tertiary center. Somatic single-nucleotide variants, small insertions/deletions, copy-number alterations, and gene co-occurrence patterns were analyzed and correlated with clinicopathological features, disease-free survival (DFS), and overall survival (OS). Results: Recurrent alterations were identified in FGFR3 (≈50%), TP53 (≈35%), STAG2 (≈25%), and PIK3CA (≈20%), consistent with established molecular pathways in UBC. Less frequent but potentially actionable alterations, including mutations in BRCA1 and ALK, were also detected, reflecting the extended coverage of the panel. TP53 mutations were independently associated with worse OS, whereas STAG2 alterations were associated with improved OS, particularly in tumors without concurrent TP53 mutations. FGFR3 mutations showed a favorable but non-independent trend. No gene retained independent prognostic significance for DFS. Co-occurrence analysis revealed an FGFR3/PIK3CA-associated pathway and relative mutual exclusivity between FGFR3 and TP53. Copy-number alterations were modest overall. Comparison with TCGA data demonstrated a higher frequency of FGFR3 alterations in our cohort, likely reflecting the larger proportion of non–muscle-invasive tumors. Conclusions: Pan-cancer targeted sequencing provided a comprehensive genomic landscape of UBC, capturing canonical drivers and additional alterations that may be overlooked by bladder-restricted assays. The identification of TP53 and STAG2 as prognostic markers highlights the potential value of broader genomic profiling for biologically informed risk stratification in urothelial bladder cancer. Full article

Triple-negative breast cancer (TNBC) cells with intact homologous recombination (HR) repair mechanism can survive treatment with Olaparib, which further limits the clinical application of PARP1/2 inhibitors. Previous studies have demonstrated that inhibition of indoleamine 2,3-dioxygenase (IDO) can enhance the sensitivity of human tumor cells to PARP1/2 inhibitors. However, the mechanisms underlying their synergistic effects in the treatment of TNBC remain unclear. Herein, we demonstrate that the combination of Olaparib and Epacadostat significantly reduces the proliferation of BRCA-proficient MDA-MB-231 and MDA-MB-468 cells compared to either monotherapy. Mechanistically, Epacadostat reduces intracellular kynurenine and NAD⁺ levels, thereby sensitizing TNBCs to PARP1/2 inhibition and significantly amplifying Olaparib-induced DNA damage. Furthermore, Epacadostat and Olaparib synergistically increase cellular reactive oxygen species (ROS), leading to DNA oxidative damage and apoptosis. In vivo, Epacadostat and Olaparib significantly suppressed MDA-MB-468 tumor growth compared to the monotherapy groups, while promoting an increase in phosphorylated H2AX. Notably, the dual inhibition of IDO1 and PARP1/2 specifically reduced the expression of HR core genes and proteins, such as BRCA1 and RAD51, which may contribute to impaired DNA-damage repair and increased sensitivity to Olaparib. In summary, targeting both IDO1 and PARP1/2 represents a promising combination therapy for BRCA-proficient TNBC. Full article

Objectives: Talazoparib (TZL) is a potent PARP inhibitor but suffers from poor aqueous solubility, dissolution-limited absorption, and dose-limiting systemic toxicities, which together restrict its antitumor efficacy in some breast cancer settings. This study aimed to develop a stearic acid-based nanoemulsion (SANE) to improve the delivery of TZL and enhance its antitumor activity and preliminarily explore its impact on DNA damage response-related pathways. Methods: SANE-TZL was prepared using a high-pressure homogenization method, and its physicochemical properties were characterized. MCF-7 and MDA-MB-231 breast cancer cells were used to evaluate cellular uptake, cytotoxicity, and changes in key DNA damage response markers. In vivo therapeutic efficacy and safety were assessed in an MDA-MB-231 xenograft mouse model. Results: SANE-TZL exhibited a uniform particle size of approximately 118 nm with excellent stability. In MCF-7 cells, SANE-TZL significantly enhanced drug internalization, resulting in an 8.4-fold reduction in IC₅₀ compared to free TZL. Consistently, in MDA-MB-231 cells, SANE-TZL also showed markedly increased antiproliferative activity. At the molecular level, SANE-TZL modulated the expression of several DNA damage response-related genes, including BRCA1, RAD51, and SLFN11, in a manner consistent with impaired DNA repair capacity. In vivo, high-dose SANE-TZL achieved a tumor growth inhibition (TGI) rate of 58.55%, which was higher than that of the free TZL group (41.86%) and the blank eSANE group (17.59%). No evident hematological or organ toxicities were observed in the SANE-TZL-treated groups. Conclusions: SANE-TZL markedly improves the delivery efficiency and antitumor activity of TZL in breast cancer models while maintaining a favorable safety profile. By combining a functional stearic acid carrier with TZL, this nanoemulsion formulation represents a safe and potent strategy to enhance PARP inhibitor-based chemotherapy in breast cancer, and it may provide a basis for further mechanistic studies on DNA damage response modulation. Full article

Background: Pancreatic cancer is a highly lethal malignancy, with a 5-year survival rate of approximately 8%. Roughly 10% of cases occur in individuals with familial pancreatic cancer or identified high-risk germline mutations, including STK11, CDKN2A, BRCA1/2, MLH1, and MSH2. Aim: We aimed to evaluate the risk of pancreatic cancer associated with inherited genetic mutations and to characterize these genetic syndromes. Methods: A systematic search of the PubMed database up to 2024 identified 1500 articles, of which 90 met the criteria for inclusion in this review. Results: High-risk individuals were defined as those with at least a 10-fold increased risk, moderate risk as 5–10-fold and low risk as under 5-fold. High-risk individuals included those with Peutz–Jeghers syndrome (132–140-fold risk), hereditary pancreatitis (50–87-fold risk), Familial Atypical Multiple Mole Melanoma syndrome (up to 48-fold risk), hereditary breast and ovarian cancer with BRCA2 mutation (up to 22-fold risk), and familial pancreatic cancer with at least three affected relatives (up to 32-fold risk). Moderate-risk patients had BRCA1, MLH1, MSH2, MSH6, p53, and ATM mutations, as well as familial pancreatic cancer with 1–2 affected kindred. Low-risk patients had familial adenomatous polyposis. Conclusions: Identifying high-risk individuals is crucial for effective genetic counseling, testing, and potential screening programs to facilitate early diagnosis and improve outcomes. Future research should prioritize large prospective cohorts, screening programs, and the integration of emerging technologies, such as AI-assisted imaging. Full article

Non-small cell lung cancer (NSCLC) is the leading cause of lung cancer deaths, with resistance to targeted therapies posing a major clinical challenge. Drug-tolerant persister (DTP) cells are key contributors to resistance, and targeting them offers new strategies to enhance existing treatments. MicroRNAs (miRNAs), particularly the tumour-suppressive miR-15/107 family, offer promise due to their ability to target multiple oncogenic pathways. This study evaluated a synthetic consensus miRNA mimic, conmiR-15/107, in NSCLC cell line models. Dose–response assays showed robust, dose-dependent growth inhibition in both EGFR-mutant (PC9) and KRAS-mutant (H358 and A549) lung adenocarcinoma cells, but not in the human bronchial epithelial cell line BEAS-2B. When combined with EGFR inhibitors (osimertinib and gefitinib) in PC9 cells, the mimics showed a higher rate of growth inhibition compared with the controls and reduced IC₅₀ values. Similarly, conmiR-15/107 enhanced growth inhibition by the KRAS inhibitors sotorasib and adagrasib in H358 cells. RT-qPCR confirmed downregulation of conmiR-15/107 targets, including MEK1, BCL2 and BRCA1, suggesting a multi-target mechanism of action. Long-term assays showed that the mimics reduced the survival and delayed the proliferation of DTPs in osimertinib-treated PC9 cells as well as sotorasib-treated H358 cells. These findings support conmiR-15/107 as a potential adjunct to targeted therapy, capable of enhancing treatment efficacy and delaying resistance in lung adenocarcinoma. Full article

Sensitive quantitative detection of breast cancer gene synthetic sequences is crucial for related biosensing research. To address the limitations of traditional sensors for detecting ultra-low concentrations, this study developed a novel fiber-optic biosensor by combining nanomaterial sensitization with nanoparticle signal amplification strategies. A fiber optic sensor based on single-mode fiber-thin-core fiber-multimode fiber-single-mode fiber structure was fabricated and functionalized with black phosphorus (BP) nano-interface. The Au@cDNA complex was prepared by covalently immobilizing sulfhydryl-modified complementary DNA (cDNA) on the surface of gold nanoparticles (AuNPs). The complex specifically hybridized with the probe DNA (pDNA) immobilized on the surface of the sensor. The experimental results show that this sensor has a sensitivity of 0.793 nm/lgM and a detection limit of 20.27 fM in the concentration range of 100 fM to 100 nM. Specifically, the BP-functionalized sensor exhibits superior dynamic range, higher sensitivity, and lower detection limits for detecting Au@cDNA. The synergistic effect of interfacial sensitization by BP and signal amplification by AuNPs significantly enhances detection performance, providing a promising platform for ultra-sensitive biosensing applications. Full article

Papillary thyroid cancer (PTC) is the most common endocrine malignancy with especially high incidence in Middle Eastern populations. While classical hereditary syndromes explain a minority of cases, the broader germline landscape of non-syndromic PTC remains unclear. Whole-exome sequencing was performed on 245 unselected Saudi PTC patients to identify germline pathogenic or likely pathogenic variants (PVs/LPVs) in cancer predisposition genes. Clinical and molecular characteristics, and family history were integrated to assess phenotypic correlations. Eleven patients (4.5%) harbored germline PVs/LPVs in cancer susceptibility genes including STK11, TP53, BRCA1, BRCA2, FANCA, SLX4, RAD50, MSH6, POLD1 and NF1. Four patients (36.4%) carried PVs/LPVs in canonical FA pathway genes; this increased to five patients (45.5%) when RAD50 was included. Two unrelated patients harbored the same STK11 variant (p.R304Q) without classical Peutz–Jeghers syndrome features. A TP53 hotspot mutation (p.R175H) was identified in a patient with a personal history of gastric cancer, a malignancy associated with Li–Fraumeni syndrome. Notably, the BRCA1 PV detected matches a known Saudi founder mutation in hereditary breast cancer, now observed in PTC. Most germline positive cases lacked syndromic manifestations, underscoring limitations of phenotype or family history-driven genetic testing strategies. These findings suggest that a small subset of non-syndromic PTC cases may carry germline PVs/LPVs in cancer predisposition genes, highlighting the need for broader genetic screening frameworks. Unbiased whole-exome analysis in unselected cohorts can uncover under-recognized genetic risk and guide screening strategies to address the unique hereditary landscape of thyroid cancer in underrepresented populations. Full article

Establishment of sister chromatid cohesion N-acetyltransferase 2 (ESCO2) is an acetyltransferase involved in sister chromatid cohesion. Here we demonstrated that ESCO2 has a new role in telomere maintenance through its binding with telomeric repeat-binding factor TRF1 and TRF2. Loss of ESCO2 induces aberrant DNA damage at telomeres and leads to dramatic telomere shortening. ESCO2 associates with several proteins involved in DNA replication and repair, including BLM, WRN, TopBP1, BRIP1, BRCA1, and MUS81. Moreover, we show that ESCO2 acts in epistasis with BLM in promoting telomere stability. Taken together, our data suggest that ESCO2 is required for the maintenance of telomere stability, presumably by coordinating multiple replication and repair factors to facilitate telomere replication and protection. Full article

Therapeutic resistance remains a major obstacle to durable cancer control, with functional reprogramming of the DNA damage response (DDR) network playing a central role. The poly(ADP-ribose) polymerase (PARP) family, particularly PARP1 and PARP2, is crucial for maintaining genomic integrity. By exploiting synthetic lethality, PARP inhibitors (PARPi) selectively target tumors with homologous recombination deficiency (HRD) and are integral to precision therapy in ovarian, breast, and prostate cancers. However, over 40% of patients with BRCA1/2 alterations develop resistance, and patient eligibility remains limited by the low prevalence of HRD mutations. In this review, we summarize the molecular mechanisms of PARPi action, resistance pathways, and emerging combination strategies. PARPi resistance arises through HR restoration (e.g., BRCA1/2 reversion mutations), replication fork protection, RAD51-mediated strand invasion, and metabolic reprogramming. Combination therapies, integrating PARPi with histone deacetylase inhibitors, cyclin-dependent kinase inhibitors, immune checkpoint blockade, or radiation, enhance efficacy by converging on DNA repair pathways and the tumor immune microenvironment. A deeper understanding of coordinated DDR regulation and rationally designed combination regimens will be essential for overcoming PARPi resistance and advancing adaptive, precision-based therapeutic strategies. Full article

Ovarian cancer is a devastating disease that is often diagnosed in the late stages. The typical therapeutic approach includes surgery plus cytotoxic drugs such as carboplatin and paclitaxel. In recent years, the advent of poly ADP-ribose polymerase (PARP) inhibitors such as olaparib has offered additional treatment opportunities for patients with BRCA mutations or homologous recombination deficiencies. Nevertheless, resistance to therapy usually occurs, leading to poor overall survival. Therefore, novel treatments are needed for this disease. One of the obstacles to successful treatment is the highly immunosuppressive nature of the ovarian cancer microenvironment. Recent strategies for the treatment of ovarian cancer and other types of cancer involve targeting the metabolism of cancer cells and other cells of the tumor microenvironment. One drug that has been investigated both in preclinical studies and clinical trials as an antitumor agent is metformin. This drug, typically used for the treatment of type-2 diabetes for its capability to lower blood glucose, can directly affect cancer cell growth and survival by activating the AMPK (adenosine monophosphate-activated protein kinase) pathway. Furthermore, it can affect the phenotype of other cells of the tumor microenvironment such as macrophages and T cells. In this review, we summarize the main characteristics of ovarian cancer and describe preclinical studies and clinical trials involving metformin as a therapeutic agent for this disease. Full article

Chemotherapy has significantly improved survival in breast cancer and, in the neoadjuvant setting, contributes to tumor downstaging and increased rates of breast-conserving surgery while enabling in vivo assessment of tumor biology and chemosensitivity. Pathological complete response (pCR) is a key endpoint associated with favorable outcomes; however, tumor heterogeneity highlights the need for reliable predictive biomarkers. This study evaluated the mRNA expression of 13 candidate genes in relation to molecular subtypes and pathological response to neoadjuvant chemotherapy (NAC) to identify potential predictive and prognostic markers. Pretreatment core biopsies from 92 patients receiving NAC were analyzed by quantitative RT-PCR. Molecular subtypes were determined by immunohistochemistry (ER, PR, HER2, Ki67), and pathological response was classified using the Miller–Payne scale as good (MP 4/5) or poor (MP 1–3). Multivariate logistic regression assessed associations between gene expression, subtype, and pCR. Hormone receptor-positive tumors showed significantly higher expression of AXL, FGFR1, RAP80, GAS6, BTRCP, and ZNF217. Significant associations with pCR were observed for AXL, FGFR1, YAP, and BRCA1. Low AXL and BRCA1 expression levels were independently associated with pCR. In addition, their combined low expression was associated most strongly with breast pCR in this cohort. These findings should be interpreted as exploratory and require validation in independent cohorts. Full article