British Journal of Cancer

BackgroundMesonephric-like adenocarcinoma has been recently classified as a rare type of ovarian carcinoma. Description of these tumours have been rare and mostly covered in case reports. In some cases, molecular characterization by sequencing has been employed for guided therapy recommendations, however, functional chemosensitivity testing of targetable pathways using advanced in vitro cellular models such as organoids has not been reported so far. Here, we report on a case of ovarian cancer that was later identified as mesonephric-like adenocarcinoma at an advanced stage. MethodsThe tumour was characterized by molecular techniques including immunohistochemistry and whole-exome sequencing. At the same time, ovarian cancer organoids were established by adapting existing protocols for high-grade serous ovarian carcinoma. The organoids were subsequently used for functional in vitro chemosensitivity testing by treatment with standard-of-care chemotherapeutics cisplatin, paclitaxel, and the Poly (ADP-Ribose) Polymerase 1-inhibitor olaparib. Based on molecular characteristics, we also applied the inhibitor binimetinib, to target Mitogen-Activated Protein Kinase downstream of the KRAS Proto-Oncogene. Additionally, chemotoxicity testing with healthy fallopian tube organoids and high-grade ovarian cancer organoids was applied to determine the therapeutic window. ResultsImmunohistochemical analysis showed characteristic PAX8+, GATA3+, TFF1+, ER-, PR-, WT1- staining while the sequencing revealed mutations in 31 genes of which KRAS G12V and DYNC1H1 G4072S were annotated as (likely) pathogenic. The tumour was mismatch-repair proficient. Tumour-derived organoids proved to be highly resistant to standard-of-care chemotherapeutics cisplatin, paclitaxel, and olaparib, but sensitive to inhibition by binimetinib, which aligned well with the molecular characteristics. Direct comparison to healthy fallopian tube organoids and high-grade ovarian cancer organoids confirmed low cytotoxic potential underlining a feasible therapeutic window for binimetinib. ConclusionsFor the first time, we show that existing protocols for high-grade serous ovarian carcinoma can be used for the generation of organoids derived from mesonephric-like adenocarcinoma. These organoids could be used as an essential tool for functional precision medicine purposes. This functional data could be applied as an additional layer for molecular tumour boards diagnostics by supporting molecular datasets and even identify targetable pathways beyond genetic variations, thus offering novel therapeutic options particularly for rare and aggressive tumours.

BackgroundEpidermal Growth Factor Receptor (EGFR) inhibitors, while effective in oncology, are associated with under-characterized ocular adverse events (AEs). Prior studies have been limited in scope, lacking a comprehensive, class-wide analysis of the full spectrum of ocular toxicity, particularly for newer agents. MethodsWe conducted a disproportionality analysis of the FDA Adverse Event Reporting System (FAERS) (2001-2025). Twelve EGFR-targeted agents were evaluated against a pre-specified set of ocular MedDRA Preferred Terms. To ensure robust signal detection, a significant association was defined by [&ge;]3 co-reported cases, a Proportional Reporting Ratio (PRR) [&ge;]2.0, and a false-discovery-rate adjusted p-value <0.05. ResultsAmong 6,976,462 drug-event combinations, 20 met all signal criteria for Eyelash Abnormalities, Ocular Surface Disease, or Vision-Threatening and Intraocular Events. Trichomegaly demonstrated extreme disproportionality (e.g., panitumumab PRR= 465.3, 95% Confidence Interval [CI], 247.7-874.3). A consistent pattern of ocular surface toxicity (conjunctivitis, keratitis, blepharitis) was observed across multiple tyrosine kinase inhibitors and monoclonal antibodies, indicating a class-wide effect. Signals for serious events included corneal perforation (erlotinib, n= 7, PRR=13.9, 95% CI= 6.6-29.4) and optic neuropathy (erlotinib, n= 6, PRR= 2.9, 95% CI= 1.3-6.4). ConclusionThis analysis confirms a strong, class-wide signal for ocular toxicity across the spectrum of EGFR inhibitors, from characteristic eyelid changes to sight-threatening complications. These findings underscore the necessity for proactive ophthalmologic monitoring, including baseline assessment, in patients receiving these therapies to preserve vision and maintain quality of life during cancer treatment.

BackgroundLynch syndrome (LS) is a cancer susceptibility syndrome caused by germline pathogenic variants in DNA mismatch repair (MMR) genes. Due to increased risk of colorectal cancer (CRC), enhanced colonoscopic surveillance is recommended for heterozygote MMR-carriers. ObjectiveUsing a registry of English LS patients linked to digital National Health Service records, we aimed to assess adherence of MMR-carriers to national surveillance guidelines, and to determine the impact of surveillance on CRC incidence and mortality. DesignWe described the frequency of colonoscopies in 4,732 MMR-carriers and used logistic regression to determine predictors of surveillance adherence. For MMR-carriers with a record of surveillance and those without, we: estimated age-specific annual CRC incidence rates (AS-AIRs) and cumulative lifetime risks, assessed for stage-shift by comparing CRC stage distributions and stage-specific AS-AIRs, and estimated risks of death from CRC and any cause using Kaplan-Meier methods and Cox Proportional Hazards regression. ResultsSurveillance at a mean interval of [&le;] 3 years (n=3028) was associated with a decrease in CRC-specific and all-cause mortality, without an associated change in total CRC incidence, even after multivariate adjustment. No strong evidence of stage-shift was observed. Colonoscopic surveillance at a mean interval of [&le;] 2 years (n=1569) was associated with an increase in total CRC incidence. Incidence of early-stage cancers was also higher, with no corresponding decrease in late-stage cancers, which may reflect the short follow-up period or the impact of overdiagnosis. ConclusionThe observed reduction in all-cause mortality amongst regularly-surveilled MMR-carriers may indicate an impact of surveillance on CRC-specific mortality, though in the context of a non-randomised study likely reflects the influence of selection bias. KEY MESSAGES OF ARTICLEO_ST_ABSWhat is already known on this topicC_ST_ABSRegular surveillance colonoscopy is recommended in Lynch syndrome, though evidence to support this remains mixed. We searched PubMed for articles published from inception to 01/05/2024 using the terms "Lynch syndrome", "HNPCC", "colonoscopy", "sigmoidoscopy", "surveillance", and "screening". We found one controlled trial and several small analytical studies dating from the early 2000s which compared surveilled and non-surveilled populations and found surveillance to be associated with reduced colorectal cancer (CRC) incidence and improved survival. More recent longitudinal observational studies, most without comparator groups, found a high incidence of CRC in LS populations despite being resident in countries where surveillance was recommended. A small number of studies directly assessed time since last colonoscopy against CRC incidence and stage with mixed findings. Finally, cross-sectional comparisons between countries of CRC incidence rates and surveillance interval recommendations found no relationship between the two1,2. What this study addsHere, we conduct an observational cohort study on a large national cohort of MMR germline pathogenic variant (GPV) carriers (MMR-carriers) in England (n=4,732), comparing CRC incidence and mortality in individuals with a record of regular surveillance to those without. Through linkage of the English National Lynch Syndrome Registry to Hospital Episodes Statistics data, we are uniquely able to study a comprehensive national population of MMR-carriers and identify the dates on which colonoscopies were undertaken over time, allowing assessment of adherence to national surveillance guidelines and the impact this has on CRC outcomes. Notably, receipt of regular colonoscopy was strongly associated with deprivation as well as ethnicity. The results show that regular surveillance at an average interval of 3 years (or less) is not associated with a reduction in CRC incidence when compared to less frequent surveillance, but an apparent decrease in both CRC-specific and overall mortality is observed, even after adjustment for confounding variables. Conversely, regular surveillance at an average interval of 2 years (or less) is associated with an increase in CRC incidence when compared to less frequent surveillance, which may suggest increased diagnosis of early-stage cancers or, due to the absence of a reduction in late-stage cancers, overdiagnosis. The observed impact of surveillance on overall mortality may demonstrate the impact of surveillance on CRC-specific mortality, or, in the context of an observational (non-randomised) study, indicate that the results are subject to selection bias. How this study might affect research, practice, or policyEvidence for the benefit of surveillance colonoscopy remains mixed. Whilst polypectomy would be anticipated to prevent CRC development (thus reducing CRC incidence), several studies have observed increased frequency of CRCs in MMR-carriers undergoing frequent surveillance colonoscopy, which may reflect overdiagnosis. The selection bias inherent to observational studies of surveillance renders mortality outcomes challenging to interpret. Randomised controlled trials of colonoscopic surveillance in MMR-carriers are required for effectiveness of this intervention to be accurately assessed. Given ethical and feasibility challenges, randomised controlled trials might be complemented by quasi-experimental designs using advanced observational methods for assessing effectiveness.

Hormone replacement therapy (HRT) with oestrogen and progestogen is a common medical treatment for alleviating symptoms of menopause. Since 2015, its use has been increasing in the UK. Unscheduled bleeding can be a symptom of endometrial cancer, and guidelines state that women experiencing this should have an urgent referral for suspected endometrial cancer. However, unscheduled bleeding is also common in women taking HRT, particularly in the first few months after starting HRT or if there is a change in regimen. Current guidelines may result in women on HRT receiving referrals that are not necessary and undergoing unpleasant and invasive tests such as hysteroscopy. However, there is a lack of current information to guide recommendations. This protocol describes a cohort study in the ORCHID-e database of anonymised patient records from English primary care. We will use a cohort of women aged over 40 years starting on HRT with oestrogen and progestogen, age matched to women who have not started HRT. Exposure will be a prescription for oestrogen containing HRT with no previous prescription for oestrogen containing HRT in the previous year. Index date in each matched set will be the date of this prescription. Prescriptions for progestogen containing drugs will not be used to define the exposure, but this information will be extracted to describe the study population and for sensitivity analyses. Outcomes will be consultations for unscheduled bleeding, urgent referrals for suspected endometrial cancer, and diagnosis of endometrial cancer. Women will be followed up until they change exposure status or are otherwise censored. Women who start taking HRT in follow-up will re-enter the cohort in the exposed group. We will describe proportions of women with a code for consulting with unscheduled bleeding, proportions of those women referred for further investigation on the pathway for suspected endometrial cancer, and proportions diagnosed with endometrial cancer within one year of referral. We will investigate the diagnostic accuracy of unscheduled bleeding for endometrial cancer separately for women on HRT and those not on HRT. Analyses will be done by 6-month categories of time since index, age, calendar year, sociodemographic variables, risk factors for endometrial cancer, type of HRT. Lay SummaryMenopause is when a womans periods stop for good. This usually happens between the ages of 45 and 55, but it can happen earlier. During menopause, the level of the hormone oestrogen falls, which can cause symptoms such as hot flushes, night sweats, poor sleep, low mood and vaginal dryness. For some women these symptoms are mild, but for others they can be very difficult and affect daily life. Many women use hormone replacement therapy (HRT) to help manage symptoms of the menopause by replacing some of the hormones their body no longer makes. The use of HRT has been increasing, including higher doses, starting at younger and finishing at older ages. Bleeding is a common side effect in women starting on HRT. It is also a symptom of womb cancer. Current guidelines for womb cancer are that women who have unscheduled bleeding after the menopause should have an urgent referral for further tests for possible cancer. However, these guidelines were written when fewer women were taking HRT. Some women on HRT might be undergoing unnecessary investigations for suspected womb cancer. Right now, doctors do not have enough clear information to know if current guidance needs to change. In this study, we will use safely stored health records where no one can be identified. We will look at women aged 40 and over who have recently started HRT, and compare them with women of the same age who are not using HRT. By following this information over time, we can see what happens to them. We will look atHow often women and other people with a womb contact their GP because of unscheduled bleeding. How often they are then sent for urgent tests that check for cancer. How often cancer is found within a year of these tests. How useful unscheduled bleeding is as a warning sign of cancer for people using HRT. If there is enough information, we will also look at whether results are different for people depending on factors such as how long they have been using HRT, their age, the type of HRT they take, their background, where they live, their general health, and their social class. The results will help us to understand how women on HRT with unscheduled bleeding are referred for further investigations on the suspected cancer pathway. They will provide evidence for the development of new guidelines for unexpected bleeding and cancer of the womb that are more relevant to women on HRT.

BackgroundChemo-resistance remains a major clinical challenge in Oral Squamous Cell Carcinoma (OSCC), attributed to the intrinsically resistant cells. Although tumour-derived extracellular vesicles (EVs) have been implicated in cell-cell communication, their role in propagating chemo-resistance remains poorly defined. This study aims to identify salivary EV-associated miRNAs capable of predicting chemoresistance and to delineate the role of miR-1307-5p in modulating CSC-driven therapeutic refractoriness. MethodsSalivary EV-derived expression profile of miR-1307-5p was assessed by qPCR in chemo resistant OSCC patients and further validated in TCGA small RNA sequencing datasets. Expression was validated by qPCR and correlated with clinicopathological outcomes. Functional assays including cell-cycle analysis, apoptosis, migration/invasion, 3D spheroids, angiogenesis, and CAM assays were performed in miR-1307-5p inhibited CD44 CSC subpopulation compared to its vehicular control. Transcriptomic profiling cross-referencing with TCGA was conducted to identify potential novel targets of miR-1307-5p. Chemo-sensitisation was assessed by treating the knockdown chemo resistant cells with low dose cisplatin and validating it using in-vitro functional assays and orthotopic xenograft model. ResultsmiR-1307-5p was significantly elevated in salivary EVs of chemo resistant OSCC patients and correlated with poor overall survival (p = 0.03). The miRNA was markedly enriched in endogenously resistant CD44 CSCs. Silencing of miR-1307-5p induced G2/M arrest, triggered apoptosis, impaired invasion, and reduced angiogenesis both in-vitro and in ex-vivo assays. Transcriptomic profiling, TCGA validation, and integrative pathway analysis identified key oncogenic hubs which converge on PI3K-AKT, MAPK/ERK, and YAP signalling pathways governing EMT. Inhibition of miR-1307-5p restored cisplatin sensitivity in resistant CSCs, with low-dose cisplatin producing substantial tumour suppression in-vitro and in-vivo. Reduced CD44 expression in xenograft models confirmed CSC reprogramming. EVs from anti-miR-treated cells confer chemo sensitisation upon uptake by resistant CSCs. Xenograft models substantiated that EVs can initiate tumour formation and that EV-mediated delivery of anti-miR-1307-5p drives significant tumour regression. ConclusionThis study identifies salivary EV-derived miR-1307-5p as a clinically relevant biomarker of chemoresistance in OSCC and reveals its mechanistic role in sustaining CSC-driven therapeutic failure. Targeting miR-1307-5p offers a promising avenue for restoring cisplatin sensitivity and developing exosome-based therapeutic strategies. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=150 SRC="FIGDIR/small/709730v1_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@19f88e0org.highwire.dtl.DTLVardef@d36b95org.highwire.dtl.DTLVardef@3c2579org.highwire.dtl.DTLVardef@c04ef5_HPS_FORMAT_FIGEXP M_FIG C_FIG

Background and AimsA major goal of personalised liver oncology is the ability to make targeted predictions about cancer-specific toxicity, however there are limited methods available. To address this, we validated the performance of our bioinformatics framework, TARGET-SL, through ex vivo drug screening. MethodsUsing TARGET-SL we predicted gain of function (GOF), loss of function (LOF) and synthetic lethal (SL) genetic events, and corresponding drug candidates. We validated drug predictions across hepatocellular carcinoma (HCC) cell lines, and a cohort of HCC and cholangiocarcinoma (CCA) patient-derived organoids (PDOs). ResultsFor HCC cells and PDOs we found 37.5% and 25% of the respective selected compounds induced unique target-specific growth inhibition based on genetic biomarkers, suggesting novel biomarker-driven drug sensitivities. ConclusionsOur analyses demonstrate TARGET-SLs potential to enhance personalized drug screening for liver cancer, by focusing on genetically informed targets. This will reduce experimental costs and accelerate the pace of therapeutic discovery. Impact and ImplicationsPrimary liver cancer (PLC) is a cancer with poor prognosis, and current therapies increase survival only for a minority of patients. Through the application of TARGET-SL we can predict, for each patient, the essential genes and corresponding small molecule inhibitors. These data support further investigation in larger patient cohorts and offer the possibility to specify new small molecule inhibitors and to repurpose current drugs for PLC treatment. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=81 SRC="FIGDIR/small/725819v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@10cb252org.highwire.dtl.DTLVardef@8f3049org.highwire.dtl.DTLVardef@ab4467org.highwire.dtl.DTLVardef@17f9d3_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LITARGET-SL can predict gene and drug sensitivities for cell lines and patient-derived organoids C_LIO_LIThis may reduce drug screening costs and accelerate the pace of therapeutic discovery. C_LIO_LITARGET-SL may assist in the repurposing of current drugs and their rapid translation for primary liver cancer C_LIO_LITARGET-SL is tumour-type agnostic, and therefore may have application in other cancers with poor prognosis C_LI

PurposeProgastrin, aberrantly expressed in colorectal cancer (CRC), is an established trophic factor for tumour epithelial cells. Whether it also promotes CRC progression by reprogramming stromal fibroblasts remains unclear. We investigated progastrin-induced colonic fibroblast activation and its functional consequences on CRC cell migration. MethodsFibroblast activation was assessed in the colonic mucosa of hGAS mice and in the human normal colonic fibroblast line CCD18Co exposed to synthetic progastrin. The impact of tumour-derived progastrin on epithelial cell motility was analysed using HCT116 cells expressing a control shRNA (shLuc) or a progastrin-targeting shRNA (shPG) in transwell migration assays performed with or without fibroblasts. Candidate paracrine mediators were evaluated by RT-qPCR, ELISA and neutralization experiments, and signalling was interrogated using the PI3K inhibitor LY294002. ResultsColonic fibroblasts from hGAS mice displayed stromal FAP and SMA expression, indicating fibroblast activation in vivo. In CCD18Co cells, progastrin increased FAP and SMA protein levels. Fibroblasts enhanced HCT116 cell migration. This effect was stronger when tumour cells expressed progastrin or when fibroblasts were preconditioned by progastrin-producing HCT116 cells. Progastrin induced CXCL12/SDF-1 and CXCL8/IL-8 expression and secretion by fibroblasts, and neutralization of either chemokine abrogated the additional migratory effect conferred by progastrin-activated fibroblasts. Progastrin triggered sustained Akt phosphorylation in fibroblasts, while PI3K inhibition suppressed CXCL12 and CXCL8 secretion and abolished fibroblast-dependent tumour cell migration. ConclusionThese data identify a stromal dimension of progastrin signalling in CRC and support a model in which tumour-derived progastrin activates colonic fibroblasts and elicits a PI3K/Akt-dependent paracrine programme that enhances CRC cell migration.

BackgroundMulticancer early detection tests could be used for cancer screening, but may lead to harms, including false positive results and overdiagnosis of indolent tumours that would not have become clinically evident during that persons lifetime. We assessed the potential for these screening harms in the context of future population-based screening with a multicancer early detection test. MethodsWe used a microsimulation model to assess potential population-level impacts of screening at ages 50-75 years with a multicancer early detection test in Canada. We assumed high test specificity (97-99.1%) and test sensitivity increasing with cancer stage. The model includes latent indolent cancers that would not be diagnosed within that persons lifetime but can be overdiagnosed through screen-detection. We calculated the yearly and cumulative lifetime probabilities of screening overdiagnosis and false positive test results, assuming a range of preclinical screen-detectable periods (2-5 years). ResultsAn estimated 2.1-6.0% of all yearly screen-detected cancers with a multicancer screening test were predicted to be overdiagnoses across scenarios. The proportion of overdiagnosis varied by site, and strongly increased with age, going from 1% at age 50 to over 10% of screen-detected cancers by age 75. The test positive predictive value ranged from 15.9%-77.6%, meaning that there could be 0.3-5.3 false positives with no underlying cancer for every true cancer case detected by the test. ConclusionPopulation-level multicancer screening with a multicancer early detection test would likely not lead to substantial screen-related overdiagnosis. Healthcare systems should consider how screening false positives may increase their diagnostic service caseload.

ObjectiveThe purpose of the present study is to describe the survival outcomes of patients with low-grade serous ovarian cancer (LGSOC) in the post-operative setting from a tertiary gynecologic oncology referral centre in Quebec, including evaluation of patient characteristics, clinical outcomes and prognostic factors. MethodsThe study included 25 patients: 1) with a post-surgical histopathologic diagnosis of a low-grade serous tumour of the ovary, 2) underwent primary cytoreductive surgery prior to adjuvant therapy, and 3) for whom clinical data was available. Clinical and demographic features were characterized by descriptive statistics. Clinical endpoints of progression-free survival (PFS) and overall survival (OS) were assessed, utilizing the Kaplan-Meier method for estimating survival probabilities. ResultsThe median age of this cohort was 61 years (range, 26-81). Median OS was 140.6 months in patients with no residual disease (R0), 71 months in patients with microscopic residual disease (R1), and 27.7 months in patients with macroscopic residual disease (R2) (p=.001). Residual disease was also found to significantly impact PFS (p=.008). Administration of adjuvant chemotherapy failed to improve survival outcomes altogether (PFS, p = .270; OS, p = .300). ConclusionsThis study supports the shifting consensus that optimal cytoreductive surgery, where feasible, is paramount for successful treatment of LGSOC. Furthermore, treatment with adjuvant chemotherapy may lead to worse survival outcomes.

Purpose: High-quality population-based cancer registration data is crucial for cancer research. We describe the methodology that the National Disease Registration Service (NDRS) established to accelerate provision of cancer registration data in England to support timely analysis of the NHS-Galleri trial (NCT05611632), assessing the clinical utility of a multi-cancer early detection test for population screening. Methods: NDRS established two accelerated cancer registration products for trial participants: Expedited Core (providing complete stage data 6 months after diagnosis) and Expedited Comprehensive (providing [&ge;]6 months of follow-up clinical pathway data 11 months after diagnosis). NDRS used pre-existing data sources and methodology, plus enhanced dedicated data liaison support. Timeliness and concordance of accelerated data was assessed 6, 11, and [&ge;]19 months after diagnosis. Results: At 6-10 months after diagnosis, most (98.0%) registrations achieved Expedited Core status; at >10 months, all (100%) registrations were Expedited Comprehensive. For fact of malignant cancer and stage III/IV diagnoses, concordance between registrations at 6 and [&ge;]19 months was 96.7% and 95.6%, respectively. Conclusions: NDRS delivered staged cancer registration data 6 months after diagnosis. High concordance at 6, 11, and 19 months provides confidence in the accelerated data. This supports reporting NHS-Galleri findings more promptly than possible via routine data.

Although the retinoblastoma protein (pRB) is functionally inactivated by hyperphosphorylation in the majority of colorectal cancers (CRC) - with RB1 rarely mutated and even amplified at the genomic level - three critical gaps remain unaddressed: no study has systematically compared which first-line chemotherapeutic agent best synergizes with CDK4/6 inhibition using head-to-head quantitative analysis; functional differences between palbociclib and abemaciclib in chemotherapy combinations have not been characterized in CRC; and direct genetic evidence of RB dependency in this combinatorial context is lacking. Here, we addressed these gaps by evaluating palbociclib and abemaciclib combined with oxaliplatin, 5-fluorouracil, and SN-38 in HCT116 CRC cells, with validation in SW480 cells, RB1-silenced HCT116 cells (shRNA-RB), and non-tumoral intestinal epithelial cells (IEC-6), using quantitative drug interaction analysis (Chou-Talalay), cell cycle profiling, apoptosis assessment, and pRB phosphorylation measurement. Oxaliplatin was the most consistently synergistic partner for both CDK4/6 inhibitors (CI < 1 across all tested concentrations), while combinations with SN-38 yielded variable results and 5-FU combinations approached additivity. The oxaliplatin combination reinforced G1 arrest and enhanced cell death, with abemaciclib producing more pronounced apoptotic induction than palbociclib - an effect not explained by differential pRB target engagement (both inhibitors reduced pRB Ser807/811 phosphorylation by [~]50%), likely reflecting abemaciclibs broader kinase inhibitory profile. shRNA-mediated RB1 silencing partially attenuated the combinatorial effect, providing direct genetic evidence that the synergy is RB-dependent. Importantly, the combination did not significantly potentiate oxaliplatin cytotoxicity in non-tumoral IEC-6 intestinal epithelial cells, in contrast to the pronounced enhancement observed in tumor cells, and synergistic benefit was preserved at sub-cytotoxic inhibitor concentrations. These findings identify oxaliplatin as the optimal chemotherapeutic partner for CDK4/6 inhibition in CRC, with a mechanism involving RB-dependent potentiation of apoptosis that is preferentially active against tumor cells and maintained at clinically relevant inhibitor doses.

ObjectivesTo estimate current, and 5- and 10-year projected, number of cases of cancer per year in transgender and gender diverse (TGD) people in England, overall and by tumour type, accounting for uptake of gender affirming care (GAC). DesignPopulation-based epidemiological modelling study using an age-stratified Monte Carlo simulations approach and the NORDPRED method for predictions. SettingModels estimating cancer case numbers for TGD people in England based on publicly available 2023 cancer surveillance data and survey-based 2025 GAC access, and predicted at 5 and 10 years hence. ParticipantsTGD people aged 15 years and above. Main outcome measuresPrimary cancer cases per year overall, by gender, age group, tumour type, and current and planned GAC. ResultsThe estimated TGD population size in England is 441547 (95% uncertainty interval (UI) 429207- 452890). Total cases per year of cancer in TGD people is expected to be 966 (95% UI 882-1069) excluding non-melanoma skin. Most cases are expected to occur in people aged 60-64. The top 5 expected cancers in TGD people are breast (19%, n = 187, 95% UI 149-241), colorectal (12%, n = 117, 95% UI 106-129), lung (11%, n = 108, 95% UI 96-122), melanoma (7.1%, n = 69, 95% UI 64-74) and urinary (6.2%, n = 60, 95% UI 54-67). Total cases of cancer in TGD people are estimated to be 1740 (95% UI 1584-1934) in 5 years and 2258 (95% UI 2066-2507) in 10 years (excluding non-melanoma skin). If TGD people were able to access their planned level of GAC, this would reduce these figures to 1555 (95% CI 1386-1766) and 2012 (95% CI 1797-2282) respectively. ConclusionsThis study provides prediction of cancer cases in TGD people in England, supporting the planning of service provision and training. This is vital, as with increasing disclosure, and long wait times for GAC, cancer cases in TGD people are predicted to increase. Summary BoxesO_ST_ABSWhat is already known on this topicC_ST_ABSThe annual number of cases of cancer in transgender and gender diverse (TGD) people in England is currently unknown as gender incongruence is not collected as part of the National Cancer Registration and Analysis Service. Some gender-affirming care (GAC) interventions are known to modulate cancer risk. Use of testosterone and chest reconstruction for transmasculine people is known to reduce their incidence of breast cancer compared to cisgender women. Use of oestradiol alongside medical or surgical androgen suppression has been shown to reduce the incidence of prostate cancer in transfeminine people while increasing their risk of breast cancer, compared to cisgender men. What this study addsThis study found that there are likely to be approximately 966 cases of cancer (excluding non-melanoma skin) in TGD people per year in the UK. Though total annual cases of cancer in TGD people are expected to be 2258 in 10 years, improved access to gender-affirming care could reduce total cases to 2012 (a 11% reduction). These figures provide additional justification for funding to improve access to GAC via the National Health Service (NHS), as well as for training on the oncological needs of this population.

BackgroundOpportunistic nutrient uptake is a hallmark of cancer metabolism. Cancer cells upregulate macropinocytosis to acquire extracellular nutrients to support growth and stress adaptation. We previously showed that extracellular ATP (eATP) is internalized by macropinocytosis and promotes multiple cancer phenotypes. Here, we tested whether eATP uptake is prevalent across cancers and whether eATP also induces senescence through purinergic receptor (PR) signaling. MethodsIntracellular ATP (iATP) levels were measured following eATP exposure across multiple cancer cell lines. eATP internalization was visualized in vitro and in vivo using a non-hydrolyzable fluorescent ATP analog together with high-molecular-weight dextran as a macropinocytosis marker. Senescence was quantified using three SA-{beta}-galactosidase assays and flow cytometry. Pharmacologic inhibitors of macropinocytosis and purinergic receptors were used to define pathway dependence. Combination treatments with the glucose transporter inhibitor DRB18 and the senolytic navitoclax were evaluated for antiproliferative effects. ResultseATP produced dose- and time-dependent increases in iATP across diverse cancer cell types. Imaging demonstrated widespread macropinocytic internalization of ATP in vitro and in tumor xenografts. eATP induced senescence in NSCLC cells, confirmed by multiple {beta}-gal assays and flow cytometry. PR inhibition significantly reduced senescence, whereas macropinocytosis inhibition had minimal effect on senescence induction. ConclusionseATP acts through dual pathways in cancer cells: macropinocytic internalization that elevates iATP and PR signaling that drives senescence. Targeting metabolic uptake together with senolytic therapy may offer a novel anticancer strategy.

BackgroundAppendiceal adenocarcinoma (AA) is a rare cancer with limited treatment options. KRAS is the most commonly mutated gene in AA and a promising therapeutic target, but its preclinical and translational relevance in AA remains unclear. MethodsWe evaluated KRASG12D-specific (MRTX1133) and pan-KRAS inhibitor (RMC-6236) in KRASmut organoid and orthotopic PDX models of AA. Tumor-intrinsic and microenvironmental responses were characterized using multi-omics profiling. Clinical outcomes were also assessed in six heavily pre-treated AA patients treated with KRAS inhibitors. ResultsMRTX1133 was highly effective for KRASG12D organoids (IC50=4.1 nM); both KRASG12D and KRASG12V organoids were sensitive to RMC-6236 (IC50=4.4 nM vs 0.5 nM, respectively). In orthotopic PDX models of peritoneal carcinomatosis from AA, MRTX1133 significantly reduced tumor growth in the KRASG12D model TM00351, and RMC-6236 reduced tumor growth in KRASG12V model AAPDX-16. Pathologic evaluation showed dramatically reduced tumor cellularity, proliferation, and pERK expression as well as induction of apoptosis. Gene Sets Enrichment Analysis (GSEA) revealed significant downregulations of E2F targets (NES=-1.9, p-adj=0.06) and the newly developed RAS/ERK (NES=-2.3, p-adj=0.06) gene set, consistent with the observed decrease in cell proliferation. There was marked upregulation of EMT (NES=2.7, FDR<0.001) and TGF-{beta} signaling (NES=2.3, FDR=0.004) in remaining tumor cells, suggesting these pathways could confer resistance. scRNA-seq analysis of TME showed dramatic shifts in cancer-associated fibroblasts (CAFs), with KRAS inhibition driving a shift from normal fibroblasts to inflammatory CAFs, and upregulation of interferon alpha and gamma pathways, suggesting that KRAS inhibition can activate innate immune response in the setting of peritoneal metastases. In a cohort of 6 heavily pre-treated patients with AA treated with KRAS inhibitors (1 G12D, 3 G12C, 2 pan-KRAS), all had biochemical response based on CEA/Ca19-9 or ctDNA and clinical benefit by RECIST criteria (1 CR, 1 PR, 4 SD). ConclusionsWhile effective suppression of RAS/ERK signaling by KRAS inhibitors reduces tumor growth, adaptive activation of EMT and TGF-{beta} pathways may mediate resistance in KRASmut AA. Additionally, KRAS inhibition remodels TME and may enhance innate immune signaling. These findings support continued clinical development of KRAS inhibitors in AA and provide a rationale for combination strategies targeting resistance pathways and stromal remodeling.

Background and aimsTherapeutic outcomes for advanced hepatocellular carcinoma remain inadequate, despite recent advances using immunotherapy. Long-term effectiveness of systemic therapies, including second-line multi-tyrosine kinase inhibitor sorafenib, is limited by resistance mechanisms and adverse effects. Upregulated deubiquitinase UCH-L1 is frequently correlated with poor prognosis in cancers. Here, we investigated the therapeutic potential of combining pharmacological UCH-L1-inhibition with sorafenib in HCC. MethodsUCH-L1 expression was analysed in TCGA-LIHC data and patient-derived HCC tissues. Sorafenib and LDN57444 effects were evaluated in vitro in cytotoxicity and invasion assays. Gene and protein expression were examined by RT-qPCR, Western blotting and immunohistochemistry. In vivo efficacy of drug synergy was assessed in an orthotopic xenograft mouse HCC model. ResultsIn silico data-analysis revealed significantly higher UCH-L1 levels in patient HCC tumours versus non-tumour, associated with reduced overall survival. Low-dose sorafenib upregulated UCH-L1 in HCC cell line Hep3B. Paradoxically, this also promoted invasiveness and sustained MEK1/2-ERK1/2-pathway activation. Combining low-dose sorafenib with LDN57444 produced strong synergistic cytotoxicity in vitro, reverted MAPK-activation and suppressed invasion. Consistently, at low sorafenib dose co-treatment with LDN57444 completely inhibited tumour growth of Hep3B xenografts and enhanced sorafenib efficacy. ConclusionLDN57444 sensitises HCC cells to low-dose sorafenib by reverting drug-induced pro-oncogenic signalling and thereby strongly synergises with sorafenib to enhance anti-tumour efficacy in a HCC mouse model. This presents UCH-L1 as a player in treatment-induced adaptive response and supports further exploring UCH-L1-targeting in combination with sorafenib as therapeutic avenue for advanced HCC. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=144 SRC="FIGDIR/small/725527v1_ufig1.gif" ALT="Figure 1"> View larger version (37K): org.highwire.dtl.DTLVardef@176dc91org.highwire.dtl.DTLVardef@8acae8org.highwire.dtl.DTLVardef@f71bborg.highwire.dtl.DTLVardef@1f3c5aa_HPS_FORMAT_FIGEXP M_FIG C_FIG Lay summaryThis study explores a new treatment approach for hepatocellular carcinoma (HCC) by combining two drugs: LDN57444, which blocks the enzyme UCH-L1, and sorafenib, a FDA-approved multi-tyrosine kinase inhibitor. We evaluated the effect of this drug combination in vitro using a HCC cell line and in an mouse HCC-model. The drug combination displayed strong, synergy in lowering HCC cell viability, and greatly reduced invasiveness and in vivo tumour growth. LDN57444 sensitised HCC cells to low doses of sorafenib by preventing UCH-L1-mediated activation of pro-oncogenic signalling. These findings highlight the potential of this new drug combination for treating advanced HCC thereby potentially reducing side-effects and countering drug resistance. Impact and implicationsOur preclinical research introduces a novel combination strategy against advanced HCC that holds potential to improve existing therapies, particularly the second-line multi-tyrosine kinase inhibitor sorafenib. The proposed combination of sorafenib with an inhibitor of the deubiquitinase UCH-L1 not only enhances sorafenib efficacy but present promise to also counter resistance mechanisms. Moreover, because effective responses are achieved at lower drug doses, this may in addition reduce therapy-associated adverse effects further increasing potential impact. While sorafenib is FDA-approved, the UCH-L1 inhibitor LDN57444 needs further (clinical) development to bring our promising findings to full translational potential for HCC patients and physicians.

Background and objectiveHighrisk nonmuscleinvasive bladder cancer (HRNMIBC) is treated with transurethral resection and intravesical BCG instillations, yet {approx}50% recur and 20% progress to invasive disease. Although molecular subtyping, e.g., BCG-response-subtype (BRS), is associated with progression risk and may aid risk stratification, yet is costly and time-consuming. Intratumoral heterogeneity complicates accurate subtyping. To address these challenges, we developed a deep-learning model that predicts BRS from routine hematoxylin-eosin-stained images. We verified the models area-by-area predictions against tissue-level gene-expression maps. Methods and participantsHematoxylin-eosin-stained images from 231 HR-NMIBC patients with known BRS were used to develop a deep-learning model through cross-validation, then validated in 83 independent samples. The models spatial predictions were assessed using spatial transcriptomics to map gene expression to tissue locations in five HR-NMIBC tumors. Outcome measurements and statistical analysisDiscriminative ability for BRS3 vs. BRS1/2 was measured by AUC. Spatial alignment was assessed by calculating Pearson and Spearman correlation coefficients between model predictions and BRS fractions; significance was assessed through permutation analysis. Key findings and limitationsThe trained algorithm achieved AUC of 0.79 (development) and 0.71 (external) to detect BRS3 vs BRS1/2. Tile-level correlation between model output and molecular labels was significant (Pearson r = 0.33-0.44; p [&le;] 0.002). Limitations include retrospective sampling and limited spatial transcriptomic cases. Conclusions and clinical implicationsOur trained algorithm showed potential to stratify HRNMIBC patients by clinically relevant BCGresponse subtypes using routine hematoxylin-eosin-stained images and showed predicted spatial heterogeneity comparable to molecular profiling. Prospective validation is required before any clinical implementation. Patient summaryStandard pathology images contain hidden details related to tumors molecular subtype. We trained an AI model to read these routine images and identify specific bladder cancer subtypes associated with poor response to BCG therapy. This approach may help reveal molecular subtype-associated information from routine pathology images, without additional laboratory procedures.

PurposePDPK1 functions downstream of PI3K and is essential for activating AKT and other AGC kinases. Although PDPK1 has a central role in the PI3K/AKT/mTOR signaling pathway, there has been limited evaluation of it as a target for cancer therapy. Anaplastic thyroid cancer (ATC) has one of the highest mortality rates of all human malignancies. Although combined BRAF and MEK inhibition in BRAF V600E-mutant ATC (45% of cases) results in response, resistance is common, and there is no curative treatment. The majority (up to 95.8%) of ATC cases have activation in the PI3K/AKT/mTOR and RAS/RAF/MEK/MAPK pathways due to genetic alterations (including driver mutations and genomic gains/losses), involved in these pathways. In this study, we investigated PDPK1 as a therapeutic target for ATC. Experimental designWe used in vitro, ex vivo, and in vivo ATC models to evaluate the effect of targeting PDPK1 (BX795) alone and in combination with mutated BRAF V600E inhibition (dabrafenib), and the mechanism of action that resulted in ATC cell death. ResultsBX795 monotherapy significantly reduced ATC cell proliferation, invasion, colony formation, and spheroid size. The combination of BX795 with dabrafenib produced strong synergistic antitumor activity in BRAF V600E-mutant ATC models. Dual inhibition led to simultaneous and sustained suppression of PDPK1/AKT and MAPK signaling, preventing the compensatory pathway reactivation observed with single-agent treatment. This integrated blockade induced pronounced oxidative stress, DNA damage, and G2-phase cell-cycle arrest, accompanied by mitochondrial dysfunction and robust activation of apoptotic cascades. These effects translated into marked tumor regression in in vitro, ex vivo, and in vivo experimental systems. ConclusionsOur findings identify PDPK1 as a critical and therapeutically tractable vulnerability in anaplastic thyroid cancer. Co-targeting PDPK1 and BRAF V600E produces potent synergistic antitumor activity by shutting down convergent oncogenic signaling nodes and amplifying apoptotic stress responses. These data support PDPK1 inhibition--alone and in combination with BRAF blockade acts as a promising strategy to improve outcomes for patients with BRAF V600E-mutant ATC.

High-Grade Serous Ovarian Cancer (HGSOC) is the most lethal gynecological malignancy due to aggressive growth, widespread metastases, and high intra-tumoral heterogeneity. Poor prognosis is largely due to late diagnosis, hence there is an urgent need to identify novel biomarkers for screening, diagnosis, and monitoring. Here, we propose the voltage-dependent calcium channel hCaV1.2 encoded by CACNA1C as a potential biomarker and therapeutic target in HGSOC. Using IHC analysis for ten ovarian cancer patients, cytotoxicity assay, TCGA gene expression and survival analyses, homology modeling, molecular docking, Calcium channel membrane assembly and molecular dynamics simulations, we tested CACNA1Cs role in HGSOC progression and the effect of blocking on cancer cell survival. We show that nifedipine (NIFE), a calcium channel blocker (CCB), had a tumor suppressive effect based on binding models predicted by three-dimensional computer assisted molecular modeling and in vitro validation using human HGSOC cell line. Using The Cancer Genome Atlas ovarian public cohort, we found CACNA1C mRNA expression strongly correlated with poor patient survival for late-stage and metastasis than primary. We also show strong correlation of CACNA1C protein expression using immunohistochemistry correlating with COH ovarian carcinomas patients disease progression. This research demonstrates that targeting HGSOC via CCBs may be therapeutically beneficial. By establishing further in vitro, in vivo, and clinical trials using FDA approved NIFE may be repurposed to target CACNA1C for HGSOC. Novelty and ImpactHigh-grade serous ovarian cancer (HGSOC) remains lethal due to late diagnosis and drug resistance. This study identifies CACNA1C (Cav1.2) as a novel prognostic biomarker and therapeutic target in HGSOC, showing that elevated expression correlates with metastatic/recurrent disease and poor survival. Using molecular dynamics and in vitro models, we demonstrate that the FDA-approved calcium channel blocker nifedipine binds stably to Cav1.2 and suppresses tumor cell growth more effectively than cisplatin. These findings support repurposing nifedipine for biomarker-driven HGSOC therapy. Translational RelevanceLate diagnosis and progressive relapses significantly contribute to the poor prognosis of ovarian cancer. Identification of a tumor biomarker that can be used for screening, diagnosis, and monitoring is critical for improving clinical outcome. Our findings demonstrate that CACNA1C is a viable diagnostic marker for HGSOC and that its blockade with CCBs reduces tumor progression, highlighting their therapeutic potential.

1.Study questionDo singletons conceived by medically assisted reproduction (MAR) experience an elevated incidence of childhood cancers and are they at a greater risk of such cancers compared to naturally-conceived singletons? Summary answerWe found no strong evidence the adjusted risk of childhood cancers is increased for MAR-conceived singletons. What is known alreadyThere is longstanding concern children conceived via MAR may be at increased risk of childhood cancer. Current epidemiological evidence does not support such a relationship. Study design, size, durationWe conducted a retrospective population-based cohort study of 5,104,121 singletons born in Australia between 1991 and 2019. Median follow-up time varied from 4 to 10 years depending on mode of conception. Participants/materials, setting, methodsWe linked birth records to public medical insurance data of the mother to ascertain MAR conception. We classified treatment as ovulation induction/intrauterine insemination (OI/IUI) or assisted reproductive technology (ART; IVF/ICSI), with ART coded as either fresh embryo transfer or frozen embryo transfer. The cohort included 4,924,354 naturally-conceived singletons and 179,767 singletons conceived via MAR. We calculated standardised incidence ratios (SIRs) to ascertain differences in population incidence of childhood cancer, and generated hazard ratios (HRs) using flexible parametric survival models controlling for key confounders. We report absolute incidence and risk differences for both statistical approaches. Main results and the role of chanceThere was no increase in the incidence or risk of all childhood cancers combined for singletons conceived via MAR, either any MAR or specific MAR types. There was some evidence the incidence of leukemias, myeloproliferative diseases, and myelodysplastic diseases was increased after ART compared to the general population (SIR: 1.32, 95% CI 1.02-1.68; equating to 2.09, 95% CI 0.13-4.44 extra cancers per 100,000 person-years), but no increased risk after adjusting for available confounders (HR: 1.04, 95% CI 0.73-1.46). These cancers showed increased incidence and risk for those conceived via IVF (SIR: 1.54, 95% CI 1.01-2.26; HR: 1.77, 95% CI 1.06-2.95), but not ICSI (SIR: 1.27, 95% CI 0.83-1.85; HR: 0.76, 95% CI 0.48-1.22). Incidence of renal tumours was elevated after IVF (SIR: 2.37, 95% CI 1.02-4.67; equating to 1.83, 95% CI 0.03-3.99 extra cancers per 100,000 person-years) and frozen transfer ART (SIR: 2.52, 95% CI 1.09-4.97; equating to 2.12, 95%CI 0.12-5.53 extra cancers per 100,000 person-years), however risk was not elevated after adjusting for available confounders (HR: 1.06, 95% CI 0.47-2.38; and HR: 1.63, 95% CI 0.73-3.61 respectively). Limitations, reasons for cautionWe did not have information on parental cause of infertility, which could be a confounder for childhood cancer, although we did adjust for parental history of cancer. For many specific cancer types, fewer than 50 cases were observed in total. Given the number of comparisons reported and closeness of the lower-bound confidence interval to 1, we cannot exclude that a significant association between conception via IVF and leukemias, myeloproliferative diseases, and myelodysplastic diseases reflects a type I error. Wider implications of the findingsOur findings align generally with published meta-analyses on the risk of childhood cancers following MAR conception and reinforce the need for very large studies to increase confidence. Parents who have conceived via MAR and their offspring can be reassured there is not strong evidence the treatments increase the overall incidence or risk of childhood cancer. Study funding/competing interest(s)This work was funded by the National Health and Medical Research Council (NHMRC: APP1164852). Dr ARW declares that their involvement in this work was supported by employment at UNSW Sydney. Prof CMV declares payment to their institution from the National Health and Medical Research Council (APP1164852). Prof NH declares payment to their institution from the National Health and Medical Research Council (APP1164852); royalties and licenses for Berek and Hackets Gynecologic Oncology (Walters Kluwer); royalties and licenses for Hacker and Moores Essentials of Obstetrics and Gynecology (Elsevier); consulting fees from Darwin Hospital and Gold Coast University Hospital; support for attending the British Gynaecological Cancer Society meeting in Aberdeen, UK, Jun 2023; support for attending the Symposium on Gynaecological Cancer in Budapest, Hungary, Nov 2023; support for attending the International conference of the Rajiv Gandhi Cancer Centre in Delhi, India, Mar 2025; and membership of the Medical Advisory Committee for TruScreen (Australia and New Zealand). A/Prof SO declares that they received payment to their institution from the National Health and Medical Research Council (APP1164852); they received a grant from the European Society for Human Reproduction and Embryology (Open call 2022) including payment to their institution; and that they are a member of the Advisory Board of the Cervical Screening Program in Norway through The Norwegian Institute of Public Health (NIPH), for which they were reimbursed travel expenses to their institution. Prof MC declares support for Theramex European Society for Human Reproduction and Embryology registration and Fertility Society of Australia and New Zealand registration and accommodation. A/Prof USD declares that her involvement in this work was supported via an Early Career Fellowship from the Cancer Institute NSW (ID: 2020/ECF1163) and employment at UNSW Sydney. A/Prof USD also declares payment to their institution from the National Health and Medical Research Council (APP2035240) and the Medical Research Future Fund (APP2032214; APP2038377), and the Australian Research Council (DP240100072) as well as current grants from NSW Health, Prince of Wales Hospital Foundation, and unpaid involvement as an Associate Editor for the "Journal of Psycho-Oncology Research and Practice". Prof LJ declares payment to their institution from the National Health and Medical Research Council (APP1164852). Prof RJN declares they are the Chair of the Clinical Advisory Committee, Westmead Fertility; External mentor at VinMec hospital; Editorial Editor at the journal "Fertility and Sterility"; and has received funding from the National Health and Medical Research Council (NHMRC) for the NHMRC Centre for Research Excellence in Womens Health in Reproductive Life (CRE WHiRL). A/Prof CS declares stock or stock options associated with CSL Ltd, Sigma Healthcare Ltd, Resmed Inc, Medical Developments International Ltd, Vitrafy Life Sciences Ltd, Intuitive Surgical, and Steris PLC. Prof GMC declares payment to their institution from the National Health and Medical Research Council (APP1164852). Prof CV declares payment to their institution from the National Health and Medical Research Council (APP1164852); research grants receive from Merck KGaA and Ferring; payments for honoraria from Merk Ltd, Merk Sharpe & Dohme, Ferring, Organon, Gedeon-Richter for being an invited lecturer in scientific meetings/conferences on multiple occasions as well as member of advisory boards for these companies who have a commercial portfolio in the field of assisted reproduction technology (ART); and speaking fees from IBSA, Vianex, Sonapharm; travel support for their participation in scientific meetings/conferences both nationally and internationally, usually as an invited speaker for the following companies - Merck Ltd, Merck Sharpe & Dohme, Ferring, Organon, Gedeon-Richter; unpaid involvement as a Board member of the Hellenic Society of Fertility and Sterility, Member of the Editorial Board of the journal "Human Reproduction", Senior Deputy of the Coordination Committee of the Special Interest Group "Reproductive Endocrinology" of the European Society for Human Reproduction and Embryology, Member of the Editorial Board of the journal "F&S Reviews", Member of the Editorial Board of the journal "RBM Online", Member of the Editorial Board of the journal "Reproductive Biology & Endocrinology", Member of the Editorial Board of the journal "Frontiers in Endocrinology", and Member of the Editorial Board of the journal "Reproductive Sciences". SubjectReproductive epidemiology

Background and ObjectivesIntravesical gemcitabine/docetaxel (Gem/Doce) is an effective therapy for Bacillus Calmette- Guerin (BCG)-unresponsive non-muscle-invasive bladder cancer (NMIBC), achieving 50% complete responses at 2 years. However, the genomic determinants underlying response and resistance to Gem/Doce remain poorly defined. Our objective was to define the mutational landscape of BCG-unresponsive NMIBC and nominate genomic features associated with response or resistance Gem/Doce. MethodsPatients with BCG-unresponsive NMIBC treated with Gem/Doce were classified as responders (recurrence-free survival [RFS] >12 months) or non-responders (RFS <12 months). Whole-exome sequencing was performed on tumors prior to Gem/Doce treatment (n=23). Single nucleotide variants were identified and annotated using a Cancer Genome Analysis pipeline. Copy number alterations were inferred with ABSOLUTE, and clonal architecture was reconstructed using PhylogicNDT. Key Findings and LimitationsResponders demonstrated significantly prolonged time to high-grade recurrence (3.5 vs 42 months, p<0.001) and cystectomy compared with non-responders (9.5 months vs not reached; p<0.001). Non-responders exhibited higher tumor mutational burden (13.66 vs 8.71; p=0.02) and more frequent whole-genome doubling (2/2 non-responders vs 0/1 responders; p=0.33). Phylogenetic analyses revealed clonal BAP1 and subclonal BRCA2 mutations in responders, whereas non-responders harbored clonal FGFR3 mutations. Limitations include small sample size and retrospective design. Conclusions and Clinical ImplicationsDistinct genomic features underlie differential response to Gem/Doce in BCG-unresponsive NMIBC. In responders, alterations in DNA repair pathways (e.g., BRCA2) may sensitize tumors to chemotherapy, while non-responders with FGFR3 mutations may benefit from alternative targeted strategies. These findings warrant validation in larger cohorts and support the development of biomarker-driven clinical trials. Patient summaryIn this report we analyzed bladder tumors and found that some tumors respond well to treatment because they have defects in repairing DNA, making them more vulnerable to chemotherapy. In contrast, tumors that do not respond to chemotherapy harbor different genetic changes that help them survive and grow. These findings may help physicians choose more effective and personalized treatments in the future.