Search Results (894)

Background: Oral squamous cell carcinoma (OSCC) remains a major public health challenge, particularly in South Asian populations where environmental exposures such as tobacco and areca nut consumption contribute significantly to disease burden. Although genomic studies have improved understanding of oral cancer biology, population-specific genomic data from high-risk Indian populations remain limited. This study aimed to characterize the genomic landscape of OSCC using whole-exome sequencing (WES) of fresh biopsy specimens obtained from patients residing along the southwest coast of Karnataka, India. Methods: Paired tumor and adjacent normal tissues from ten OSCC samples (total n = 20 samples) were subjected to WES to identify somatic and germline-associated variants. Matched tumor–normal comparative analysis, variant annotation, and population frequency assessment using established genomic databases, including gnomAD, were performed to characterize the mutational profile. The findings were further compared with a previously analyzed regional cohort comprising 66 OSCC patients to evaluate recurrence patterns and population relevance. Results: The analysis identified a broad background of recurrent germline-associated variants alongside a comparatively limited number of tumor-specific somatic mutations, consistent with the expected predominance of constitutional genetic variation relative to acquired coding alterations in tumor samples. Recurrent variants were observed in genes associated with DNA repair, immune signaling, inflammatory responses, and pharmacogenomic pathways, including XRCC1, ITPKB, ABCB1, and OPRM1, whereas somatic alterations were primarily detected in established cancer-associated genes such as TP53, CDKN2A, and TERT. Conclusions: Several recurrent variants demonstrated high frequencies in South Asian populations, suggesting that they may represent recurrent population-associated variants of potential biological or pharmacogenomic relevance that require validation in larger cohorts. KEGG pathway enrichment analysis identified pathways related to cancer, chemical carcinogenesis, metabolic regulation, and xenobiotic response. Overall, these findings provide preliminary insights into the population-specific genomic characteristics of OSCC in this regional cohort and highlight the need for larger validation studies to determine the biological significance and reproducibility of these findings. Full article

Background/Objectives: Chronic microenvironment stress contributes to the progression of melanoma, yet practical tools for quantifying tumor stress adaptation remain limited. Methods: Using disulfiram as a system-level probe, we identified shared regulatory modules between disulfiram-related targets and melanoma-associated genes, which are integrated into pathways regulating apoptosis and hypoxia/oxidative stress. From these modules, we devised a stress adaptation score (BiScore) based on hallmark gene characteristics and assessed its prognostic significance in melanoma cohorts. Results and Conclusions: In the TCGA-SKCM dataset, a higher binuclear score correlated with poorer overall survival and remained an independent prognostic factor even after adjusting for clinical covariates. This observation was externally validated for distant metastasis-free survival rate in the GSE65904 cohort. Tumors with high binuclear expression consistently exhibited reduced immune infiltration and were weakly associated with mutation load, suggesting that the stress adaptation axis operates independently of gene mutation burden. Single-cell analyses demonstrated that stress-related signals were distributed across both malignant and stress-responsive microenvironmental compartments. In melanoma cell lines, hypoxia induces HIF-1α expression and shifts apoptosis-related proteins towards an anti-apoptotic state, and NAC attenuated CoCl₂-induced ROS accumulation. In conclusion, these findings establish BiScore as a quantitative framework for capturing stress adaptation states linked to adverse outcomes in melanoma. Full article

Background: Therapeutic resistance following cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) plus endocrine therapy (ET) represents a key unmet need in hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR+/HER2−) metastatic breast cancer (mBC). Treatment paradigms have advanced from non-targeted options, such as fulvestrant monotherapy or everolimus-based combinations, to precision medicine strategies, including inhibitors of the PI3K/AKT pathway, oral selective estrogen receptor degraders (SERDs), and novel ER-modulating agents, often guided by biomarkers and molecular surveillance. Methods: This narrative review synthesizes evidence from randomized clinical trials, real-world studies, and biomarker-driven analyses published from 2010 to 2026, with emphasis on next-generation sequencing (NGS)-guided genomic profiling, targeted pathway therapies, and circulating tumor DNA (ctDNA)-based proactive interventions in the post-CDK4/6i setting. This review was conducted and reported in accordance with the SANRA recommendations for narrative reviews. Results: Early second-line standards, including fulvestrant and alpelisib for PIK3CA-mutated tumors, established the basis for biomarker-guided treatment in hormone receptor–positive, HER2-negative metastatic breast cancer. With the widespread use of CDK4/6 inhibitors in the first-line setting, the optimal post-progression strategy has shifted toward molecularly selected combination approaches rather than single-agent endocrine therapy, as endocrine monotherapy has shown limited efficacy in acquired resistance. Multiple randomized studies have demonstrated that adding targeted agents to endocrine therapy improves progression-free survival compared with hormonal therapy alone, supporting combination regimens as the preferred strategy after CDK4/6 inhibitor progression, except in carefully selected patients with low disease burden, indolent biology, or frailty where tolerability is a major concern. Precision-based trials have further refined this approach. Elacestrant improved progression-free survival in ESR1-mutated disease in the EMERALD trial, capivasertib plus fulvestrant demonstrated significant benefit in tumors harboring AKT/PIK3CA/PTEN pathway alterations in CAPItello-291, and inavolisib plus palbociclib and fulvestrant achieved both progression-free and overall survival improvement in PIK3CA-mutated patients with early relapse in INAVO120. Real-world analyses further support the effectiveness of these biomarker-directed strategies across diverse clinical subgroups. Comprehensive genomic profiling has identified multiple resistance mechanisms, including ESR1 mutations, PI3K/AKT/mTOR pathway activation, RB1 loss, and FGFR alterations, which may co-occur and reduce sensitivity to endocrine monotherapy. While ESR1 and PI3K pathway alterations now guide approved therapies, FGFR alterations remain investigational targets, with ongoing trials evaluating selective FGFR inhibitors. Proactive switching approaches evaluated in SERENA-6 and PADA-1 demonstrate that serial circulating tumor DNA (ctDNA) monitoring can detect emergent ESR1 mutations before radiographic progression, providing a clinically actionable lead time for early therapeutic modification and extending endocrine-based disease control by approximately 5 to 7 months. Conclusions: Post-CDK4/6i management increasingly relies on NGS-guided precision approaches, integrating pathway-specific therapies and ctDNA surveillance to tailor sequencing based on resistance profiles, prior ET response, and tumor heterogeneity. Future investigations into novel ER degraders and multi-targeted combinations hold potential to further optimize algorithms, extend non-chemotherapy options, and enhance survival in HR+/HER2− mBC. Full article

Background: Cutaneous melanoma (CM) is a highly immunogenic malignant neoplasm. It features high mutational burden and intense lymphocytic infiltration, supporting the use of immunotherapies, especially inhibitors of the programmed cell death protein 1 (PD-1) checkpoint. Despite advances with anti-PD-1 therapies, such as nivolumab and pembrolizumab, many patients still experience resistance. This result highlights additional immunosuppressive mechanisms within the tumor microenvironment (TME) that limit T-lymphocyte-mediated responses. Objectives: The aim was to discuss the immunologic and metabolic bases of PD-1- and CD73-mediated pathways and evidence that CD73 inhibition can boost PD-1 inhibitor efficacy by acting on convergent immunosuppressive pathways. Methods: We conducted a narrative literature review focusing on tumor immunosuppression, purinergic signaling and checkpoint inhibitor-based immunotherapy. Results: The purinergic pathway, mediated by the ectonucleotidase CD73, is a critical regulator of tumor immunosuppression. CD73 converts extracellular adenosine monophosphate (AMP) into adenosine. This adenosine accumulates in the hypoxic and inflamed TME, exerting immunosuppressive effects. Adenosine acts as a “metabolic brake,” inhibiting proliferation, cytokine production, and cytotoxic activity of CD8⁺ T lymphocytes and natural killer (NK) cells. It also promotes the expansion of regulatory T cells (Tregs) and tumor progression. This axis may limit responses to PD-1 blockade, suggesting that complementary pathways are active. Conclusions: Integration of PD-1 and CD73 pathways suggests that CD73 inhibition may enhance PD-1 blockade by targeting convergent immunosuppressive mechanisms. This supports the exploration of combination strategies to broaden the benefits of immunotherapy in CM. Full article

Introduction: Lung cancer, the leading cause of cancer-related mortality worldwide, is a heterogeneous malignancy comprising distinct histological and molecular subtypes, with non-small cell lung cancer (NSCLC) accounting for approximately 85% of cases and adenocarcinoma (ADC) representing the most prevalent histotype. An emerging pathological feature of NSCLC, spread through air spaces (STAS)—defined as the extension of tumor cells into the lung parenchyma beyond the main tumor margin—has been associated with worse disease-free and overall survival and has been proposed as a possible predictor of recurrence to guide surgical extent. Concurrently, recent comprehensive genomic profiling of early-stage NSCLC has highlighted the need to interpret multi-omics data and their relationship with pathological variables, including IASLC histological subtypes, to better personalize treatment strategies. In this context, we investigated the overall distribution of STAS and its association with tumor mutational profiles and IASLC histological subtypes in a large real-world cohort of lung adenocarcinoma patients from the LANTERN project. Materials and Methods: In a prospective, multicenter observational study (March 2023–December 2024), 271 NSCLC patients were enrolled, and clinicopathological, immunohistochemical, and genomic data were collected; comprehensive genomic profiling was performed using the TruSight Oncology 500 assay to analyze 523 cancer-related genes, tumor mutational burden (TMB), and microsatellite instability; and STAS was assessed according to IASLC criteria. Adenocarcinoma accounted for roughly 90% of the cases, with a median age of 69 years and a predominance of stage IV disease (49.5%). STAS was evaluable in 162 cases and was detected in 17.9% of tumors. Results: STAS-positive tumors showed a higher trend towards locally advanced and advanced disease; no differences were observed in sex, age, smoking status, tumor mutational burden, or PD-L1 expression. Additionally, STAS-positive tumors showed a higher association with micropapillary, mucinous, and papillary patterns, whereas the acinar pattern was more frequent in STAS-negative tumors. The most frequently mutated genes were TP53, KRAS, EGFR, and STK11, with no significant differences between groups; ROS1 alterations were absent in STAS-negative tumors but detected more frequently in STAS-positive cases. Conclusions: Overall, these findings indicate that STAS positivity is associated with high-risk histological subtypes and advanced disease, suggesting its importance as a marker of tumor aggressiveness and emphasizing the need for its systematic evaluation in lung adenocarcinoma to better guide surgical planning and patient risk assessment. Full article

The therapeutic armamentarium for colorectal cancer (CRC) has been significantly expanded with the introduction of immunotherapy, particularly immune checkpoint inhibitors (ICIs). However, the response to immunotherapy is strongly dependent on microsatellite instability (MSI) status. Tumors with high MSI (MSI-H) and/or mismatch repair deficiency (dMMR) exhibit high tumor mutational burden (TMB), increased neoantigen load, and enhanced immunogenicity, leading to improved responses to ICIs compared with microsatellite-stable (MSS) and/or mismatch repair-proficient (pMMR) tumors. This has changed the treatment landscape of this small subgroup of metastatic CRC (mCRC), including the approval of pembrolizumab as a first-line option. In contrast, most mCRC cases are MSS/pMMR and are resistant or poorly responsive to ICIs, with no established standard immunotherapy strategy. Therefore, current approaches aim to convert these “cold” tumors into “hot,” immunologically active tumors. This review summarizes the distinct molecular basis of MSI phenotypes and their interaction with the tumor microenvironment, and provides relevant insights into current clinical evidence for prognostic and predictive biomarkers beyond MSI status, as well as novel therapeutic strategies to overcome resistance in MSS disease. Full article

Background: Lung adenocarcinoma (LUAD) remains a leading cause of cancer-related mortality worldwide. Although the lipid metabolism-associated gene PTGDS has been implicated in tumorigenesis, its functional significance and regulatory mechanisms in LUAD are poorly understood. Methods: We integrated multi-omics data from TCGA and GEO cohorts to evaluate PTGDS expression and its clinicopathological relevance. Functional characterization was performed using gain-of-function models in LUAD cell lines and a xenograft mouse model, assessing proliferation, migration, invasion, and immune microenvironment alterations. Results: PTGDS expression is markedly reduced in LUAD tissues and correlates strongly with advanced disease stage and unfavorable prognosis. Clinically, low PTGDS expression is associated with specific driver mutations and reduced tumor mutation burden. Notably, PTGDS levels correlate with enhanced cytotoxic T-cell infiltration and suppressed M2 macrophage polarization, suggesting immunomodulatory functions. Ectopic expression of PTGDS significantly suppressed malignant behaviors in vitro and tumor growth in vivo. Mechanistically, PTGDS overexpression was associated with reduced expression of CDK1 and PLK1 and increased expression of p21 and p27. Conclusions: Our findings establish PTGDS as a novel tumor suppressor in LUAD that restrains tumor progression through cell cycle modulation and immune microenvironment remodeling, highlighting its potential as both a prognostic biomarker and a therapeutic target. Full article

Background: Osteosarcoma remains a biologically complex and clinically challenging malignancy, with survival gains plateauing despite decades of multimodal therapy incorporating surgery and cytotoxic chemotherapy. Unlike cancers in which mutation-centric precision oncology has yielded transformative advances, osteosarcoma is characterized by profound structural variation, copy number alteration dominance, and dynamic clonal evolution, limiting the effectiveness of single-target approaches. These realities motivate alternative strategy-level frameworks that better align treatment selection with evolving disease behavior. Methods: This narrative educational review synthesizes contemporary evidence from osteosarcoma biology, radiobiology, and translational oncology to propose a state-based framework for integrating radiotherapy—particularly stereotactic body radiotherapy (SBRT/SABR) and spatially fractionated radiotherapy (SFRT)—into osteosarcoma management and clinical trial design. Rather than relying solely on static anatomic stage, this framework emphasizes clinically actionable, time-varying state variables, including disease burden patterns (localized, oligometastatic, polymetastatic), tempo of progression, prior systemic response, and feasibility of complete local control. Results: Within this context, radiotherapy is presented not only as a local control modality but also as a hypothesis-generating biologic intervention, capable of perturbing tumor vasculature, inflammatory signaling, innate DNA-sensing pathways, and immune/myeloid programs in a dose-, fractionation-, and spatial-distribution-dependent manner. The review critically examines both the potential opportunities (e.g., local eradication, immune modulation) and limitations (e.g., rarity of abscopal responses, risk of unintended systemic signaling) of radiobiotherapy combinations, emphasizing the need for cautious interpretation and prospective validation. Conclusions: Finally, the article outlines practical implications for state-stratified, biomarker-embedded clinical trials, highlighting endpoints beyond conventional response criteria, including circulating tumor DNA dynamics, immune and myeloid signatures, and long-term patterns of disease progression. Overall, this review frames radiobiotherapy as an educational and investigational paradigm intended to support rational hypothesis generation, multidisciplinary decision-making, and learning-oriented trial designs in osteosarcoma, rather than as definitive clinical guidance. Full article

Background: Muscle-invasive bladder cancer (MIBC) is an aggressive disease with heterogeneous responses to neoadjuvant chemotherapy and emerging chemo-immunotherapy combinations. Reliable biomarkers to predict treatment responsiveness before therapy initiation are needed to guide patient selection. Objective: The objective of this study was to identify genomic and immune-related features associated with immune-active tumor phenotypes in MIBC using The Cancer Genome Atlas bladder cancer cohort (TCGA-BLCA). Methods: A retrospective bioinformatics analysis of TCGA-BLCA data was performed, evaluating gene expression, somatic mutations, tumor mutational burden (TMB), DNA damage response (DDR) gene status, and immune infiltration signatures. Immune enrichment metrics were derived from transcriptomic data. In the absence of direct treatment response data, a surrogate immune response classification was applied. Associations were analyzed using descriptive statistics and Firth’s penalized logistic regression. Results: Tumors classified as immune-high phenotype group based on immune-related features exhibited significantly higher global immune infiltration, including increased ImmuneScore and enrichment of cytotoxic and innate immune cells. In multivariable analysis, ImmuneScore was the only independent predictor of inferred responsiveness (p = 0.003). Conclusions: Global immune infiltration showed the strongest association with immune-active tumor phenotypes among the features examined in this TCGA-based analysis. These exploratory findings suggest that immune profiling may warrant further investigation as a component of tumor characterization in MIBC, pending validation in cohorts with clinical treatment and outcome data. Full article

TP53 is the most frequently altered tumor-suppressor gene in human cancer, yet efforts to therapeutically target p53 have yielded limited and inconsistent clinical success. We argue that this gap reflects not a lack of druggable biology, but an oversimplified conceptual framework that treats p53 as a binary wild-type versus mutant entity. Here, we synthesize emerging evidence supporting a model in which p53 operates across a spectrum of functional states defined by mutation class, allelic burden, isoform composition, aggregation propensity, post-translational regulation, and cellular context. These states shape distinct biological outputs, including transcriptional activity, dominant-negative and gain-of-function effects, immune modulation, and checkpoint dependency, which collectively determine therapeutic vulnerability. We review current strategies targeting the p53 pathway, including mutant p53 reactivation, targeted degradation, anti-aggregation approaches, immune-directed therapies, restoration of wild-type pathway activity, gene replacement, and synthetic lethal targeting of DNA damage response dependencies. Clinical and preclinical evidence highlights key limitations of each approach, including stoichiometric constraints, mutation specificity, context-dependent efficacy, and adaptive resistance. Notably, emerging evidence from preclinical and correlative clinical studies suggests that therapeutic outcomes may be more closely associated with p53 functional state than with TP53 mutation status alone. We further emphasize the emerging roles of p53 isoforms and the tumor immune microenvironment as critical modifiers of p53 activity and determinants of treatment response. Collectively, these insights support a paradigm shift toward mechanism-matched, biomarker-stratified strategies that align therapeutic modality with the operative p53 network. Future progress will depend on integrating multi-parameter diagnostics with rational combination therapies to fully exploit p53 as a central vulnerability in cancer. Full article

Background: While Immune Checkpoint Inhibitors (ICIs) have significantly improved outcomes in lung cancer (LC), clinical responses remain heterogeneous. Static tissue biomarkers, like PD-L1, and tumor mutational burden (TMB) are limited by intratumoral heterogeneity and the inability to track temporal changes. This review aims to evaluate the current state and future potential of liquid biopsy as a dynamic tool for patient selection, treatment monitoring, and the identification of resistance mechanisms in LC immunotherapy. Methods: A literature search was conducted in the PubMed database up to March 2026. We identified 65 eligible publications, including clinical trials, observational studies, and systematic reviews, focusing on liquid biopsy analytes such as circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), exosomes, and soluble immune mediators. Results: Liquid biopsy provides a “pooled” representation of the total tumor burden, overcoming the spatial limitations of tissue biopsy. Key findings include that dynamic changes in ctDNA and bTMB can predict molecular progression weeks before radiological assessment; blood-based PD-L1 monitoring (soluble, exosomal, or on CTCs) correlates with survival outcomes and offers a real-time readout of immune checkpoint activity; novel markers like tumor-macrophage fusion (TMF) cells and cytokine signatures provide unique insights into the systemic immune microenvironment. Conclusions: Liquid biopsy is evolving from a complementary diagnostic tool into a central pillar of precision immuno-oncology. Although technical standardization remains a challenge, the integration of multi-omic blood-based biomarkers represents the future of personalized lung cancer management. Full article

Background and Clinical Significance: SWI/SNF chromatin remodeling complex-deficient malignancies constitute an aggressive group of undifferentiated tumors defined by inactivation of core subunits including SMARCA4 (BRG1) or SMARCB1 (INI1). In the head and neck, these tumors predominate in the sinonasal tract; oral cavity presentations are exceedingly rare, with reported cases predominantly representing metastatic disease. Peri-implant gingival masses in clinical practice are overwhelmingly reactive, but their occasional malignant nature mandates timely biopsy and thorough pathologic workup. We report the first comprehensively molecularly characterized case of a peri-implant gingival SWI/SNF complex-deficient tumor with confirmed biallelic SMARCA4 inactivation. Case Presentation: A 75-year-old man presented with a one-week history of a rapidly enlarging exophytic erythematous peri-implant gingival mass in the right posterior mandible (region 44–47). Incisional biopsy demonstrated an undifferentiated high-grade tumor with epithelioid, plasmablastoid, and focally rhabdoid morphology with necrosis. Immunohistochemistry showed complete loss of BRG1 (SMARCA4) with retained INI1 (SMARCB1), EMA positivity, Ki-67 of approximately 100%, and negativity across all lineage-specific markers (hematolymphoid, epithelial, melanocytic, endothelial, squamous). Comprehensive next-generation sequencing (Oncomine Comprehensive Assay Plus) confirmed biallelic SMARCA4 inactivation via a truncating nonsense mutation (p.Trp1346Ter; VAF 73.85%) combined with copy number loss, establishing the molecular mechanism underlying BRG1 protein loss. Co-occurring alterations included homozygous CDKN2A/CDKN2B deletion, MTAP loss (9p21.3), clonal TP53 and KEAP1 mutations, and intermediate–high tumor mutational burden (13.3 mutations/Mb) with microsatellite stability. The patient initiated carboplatin–paclitaxel and achieved a partial response at one month with further shrinkage by four months. This case illustrates a rare oral cavity manifestation of SWI/SNF complex deficiency arising in a peri-implant location, with a diagnostic workup that required integration of immunohistochemistry and molecular profiling for definitive characterization. The MTAP deletion co-occurring with homozygous CDKN2A/B loss identifies a potentially actionable synthetic lethal vulnerability to MAT2A and PRMT5 inhibitors currently under clinical investigation. An occult primary site could not be fully excluded due to absence of a dedicated staging workup. Conclusions: Rapidly enlarging peri-implant gingival masses should prompt timely biopsy and SWI/SNF marker testing when histology is high-grade and lineage-ambiguous. NGS-based molecular profiling confirms diagnosis, elucidates mechanism, and reveals actionable targets in this rare tumor class. Full article

Neuroblastomas (NBs) are aggressive, therapy-resistant embryonal tumors of neural crest origin, which despite low mutational burdens exhibit high intra-tumoral heterogeneity characterized by adrenergic, noradrenergic, mesenchymal and cancer stem cell (CSC)-like subpopulations. These phenotypes exhibit interconverting plasticity that reflect both stage of transformation during sympathoadrenal development and conditions within the tumor microenvironment. Chemotherapeutic agents promote adrenergic-to-mesenchymal conversion in NBs, which underpins drug resistance, post-therapeutic relapse, metastatic progression, and the plateauing of responses to advances in multimodal therapy. Improved understanding of the molecular mechanisms that regulate NB phenotypic plasticity is essential for identifying novel prognostic markers and potential therapeutic targets. In this article, following introductions into NB, molecular regulation of NB phenotypic plasticity, and the NF-Y transcription factor and its role in development and differentiation, we focus on alternative NF-YAl, NF-YAs and NF-YAx splicing of the NF-Y subunit, NF-YA, and the potential influence that different NF-YA isoforms have on NF-Y function and the NF-Y-transcription factor networks that impact NB cell phenotypes. Particular attention is paid to the novel extra short-form NF-YAx isoform, originally detected as the exclusive NF-YA isoform in a non-MYCN amplified advanced stage 3 NB. This isoform is also induced by doxorubicin in non-Myc amplified SH-SY5Y NB cells and is involved in doxorubicin cytotoxicity. Despite high cytotoxicity, however, NF-YAx selects a resistant subpopulation with mesenchymal/neural crest stem cell-like identity, unveiling a doxorubicin-induced NF-YAx-dependent resistance mechanism, with potential to influence post-therapeutic relapse and disease progression. Therefore, evaluating alternative NF-YA splicing, and especially NF-YAx expression, in advanced stage and post-therapeutic relapsed NBs, may be of both prognostic and therapeutic significance. Full article

Immune checkpoint receptors (ICRs) play a pivotal role in modulating antitumor immunity and have become central targets in the immunotherapy of genitourinary (GU) malignancies. This review provides a comprehensive overview of the fundamental mechanisms of ICR signaling, the expression and pathophysiological roles of these receptors in GU cancers (kidney, bladder, prostate, testicular, and penile), and the evolving therapeutic landscape. Key ICRs, including PD-1, CTLA-4, LAG-3, TIM-3, and TIGIT, orchestrate complex signaling cascades that can lead to T-cell exhaustion and tumor immune evasion. Their expression varies significantly across GU cancer types, histological subtypes, and tumor stages, influencing prognosis and therapeutic response. Immune checkpoint inhibitors (ICIs) reinvigorate antitumor immunity by disrupting these inhibitory pathways and remodeling the tumor microenvironment (TME); however, resistance mechanisms (primary, adaptive, and acquired) and immune-related adverse events (irAEs) pose significant clinical challenges. Established biomarkers such as PD-L1 expression, tumor mutational burden (TMB), and microsatellite instability (MSI)/deficient mismatch repair (dMMR) status guide ICI use, but their predictive power has limitations. Consequently, emerging tissue-based (e.g., immune cell signatures, multiplex IHC/IF, spatial transcriptomics), liquid biopsy-based (e.g., ctDNA, CTCs, exosomes), and imaging-based (radiomics, AI-driven analysis) biomarkers are under active investigation to refine patient selection and monitor treatment efficacy. The therapeutic armamentarium is rapidly expanding with novel ICIs targeting new receptors, bispecific antibodies, and innovative combination strategies involving ICIs with chemotherapy, targeted therapies, radiotherapy, and other immunotherapies. Furthermore, ICIs are increasingly explored in neoadjuvant, adjuvant, and maintenance settings. This review highlights the dynamic progress in understanding ICR biology and its clinical translation, emphasizing the ongoing efforts to develop more personalized and effective immunotherapeutic strategies for patients with genitourinary tumors. Full article

A circulating tumor DNA (ctDNA) assay is an emerging non-invasive diagnostic approach providing real-time insights into the heterogeneous tumor molecular landscape of advanced prostate cancer, overcoming the limitations of traditional tissue biopsies and PSA. Detection methods include droplet digital PCR, next-generation sequencing, and new epigenomic and fragmentomic strategies (investigational) designed to improve sensitivity in cases of low ctDNA shedding. While ctDNA’s role in localized prostate cancer is limited, it offers significant prognostic value in metastatic cases, where high ctDNA levels correlate with shorter survival. Additionally, longitudinal ctDNA monitoring can predict treatment response and identify emerging resistance mechanisms, including androgen receptor alterations associated with androgen receptor pathway inhibitor therapy and BRCA reversion mutations linked to PARP inhibitors. Importantly, liquid biopsy enables genomic characterization to inform treatment decision-making, particularly in clinical scenarios where tissue biopsy is challenging, such as bone-only disease. However, the widespread clinical implementation of ctDNA analysis is hindered by several analytical challenges, including low sensitivity in localized disease and low disease burden, and the risk of false positives due to clonal hematopoiesis. Furthermore, greater efforts are required to standardize pre-analytical workflows and post-analytical data interpretation and reporting across institutions. This review aims to summarize the evolving role of cfDNA technologies in localized and advanced prostate cancer, highlighting their prognostic and predictive value and their role in uncovering mechanisms of treatment resistance. Full article