DNA double-strand breaks (DSBs) that occur during mitosis are primarily repaired by Polθ-mediated microhomology-mediated end joining (MMEJ). The CIP2A–TOPBP1 complex has been shown to tether broken chromatin at mitotic DSBs, but whether it coordinates with or functions independently of Polθ remains unknown. Here, we show that the CIP2A–TOPBP1 complex is recruited to mitotic DSB sites, where it directly interacts with Polθ and corecruits Polθ to chromatin. CIP2A sustains Polθ phosphorylation by inhibiting PP2A, thereby prolonging Polθ chromatin retention and enabling efficient repair. Upon repair completion, the CIP2A–TOPBP1 complex dissociates, PP2A dephosphorylates Polθ, and Polθ is released from chromatin. Loss of CIP2A impairs tumor growth, while disruption of CIP2A–Polθ binding leads to persistent DNA damage, micronucleus formation, and synthetic lethality in BRCA1/2-deficient cells. These findings uncover a cooperative mechanism by which CIP2A–TOPBP1 dynamically regulates Polθ in mitotic DSB repair and provide insights into the synthetic lethal interaction of CIP2A with BRCA1/2 under radiotherapy.
TNK1 is a targetable JAK-independent driver of STAT signaling and inflammation
Deregulated inflammatory signaling via STAT family transcription factors, particularly STAT1, underlies a variety of immune-related diseases, including inflammatory bowel disease. Whereas activation of STATs by JAKs via canonical receptor-driven JAK–STAT signaling is well understood, little is known about JAK-independent mechanisms of STAT activation. Here, we identify the understudied nonreceptor tyrosine kinase TNK1 as a therapeutically targetable, JAK-independent activator of STAT signaling. Using a multiomics approach, we mapped a network of TNK1 substrates associated with protein condensates and proinflammatory signaling, including STAT1. We found that TNK1, but not its sister kinase ACK1, directly phosphorylates STATs at well described STAT-activating JAK sites. In cells, TNK1-mediated STAT1 phosphorylation and activation occurs independently of JAKs. Imaging and interactomics data suggest that TNK1 interacts with STAT1 in cytosolic condensates, which likely compartmentalize TNK1-substrate interactions. We show that an intrinsically disordered proline-rich region in TNK1, which includes a 14-3-3 docking phosphorylation site, is required for the formation of kinase-active TNK1 condensates and STAT1 phosphorylation. Mutations within the proline-rich region that eliminate 14-3-3 binding increase formation of TNK1 condensates, suggesting a model in which 14-3-3 acts as a clamp that constrains the flexible PRR to inhibit condensate formation and STAT1 activation. Finally, we show that TNK1 is a targetable driver of STAT1-mediated inflammation in the gut as inhibition of TNK1 reduces active STAT1 in the colon and ameliorates colitis symptoms in mice.
Effect of time to palliative epilepsy surgery on outcomes
Abstract Objective Epilepsy duration is a modifiable risk factor in the outcome of definitive epilepsy surgery; however, an analogous effect in palliative procedures has not been shown. We reviewed the Pediatric Epilepsy Surgery Database data for an association between epilepsy duration and seizure reduction in palliative procedures. Methods Patients enrolled between January 2018 and April 2025 who underwent their first epilepsy surgery with palliative intent with 6 months of follow‐up were included. Procedures included neuromodulation, corpus callosotomy, hemispherotomy, lesionectomy, and lobectomy where surgical intent was not seizure freedom. Outcomes of seizure freedom, 90% seizure reduction, and 50% seizure reduction were considered at 6–12 months and >12 months from surgery. Duration from epilepsy onset to surgery was compared for patients above and below each outcome threshold at each time point. Logistic regression analysis for the association between epilepsy duration and seizure reduction adjusted for potential confounders including procedure type, etiology, and other clinical factors. Logistic regression analysis was performed on the overall cohort and subgroups of patients with each procedure. Results A total of 588 patients were included. Initial univariate analysis suggested that epilepsy duration at time of surgery was significantly associated with seizure freedom and 90% seizure reduction at both 6–12 months and >12 months. After adjusting for confounders, only seizure freedom at >12 months was significantly associated with duration of epilepsy. When individual procedures were considered, only lobectomy was sensitive to duration of epilepsy in multivariate analysis, with significant impacts on >50% and >90% seizure reduction at >12 months. Lesional epilepsy predicted seizure freedom at >12 months. Neuromodulation and corpus callosotomy were less likely to achieve seizure reduction than other procedures. Significance We did not find an association between early epilepsy surgery and seizure reduction. This reflects the heterogeneity of our population, including different types of surgical procedures and lesional and nonlesional epilepsies.
Continuous Glucose Monitoring in Type 2 Diabetes and Beyond
Importance Continuous glucose monitoring (CGM), initially recommended primarily for people with type 1 diabetes, has rapidly expanded to patients with type 2 diabetes and, more recently, even to individuals without diabetes. This broadening use underscores the importance of critically examining the evidence supporting CGM across populations, clarifying where benefits are established, where they are modest, and where they remain uncertain. Observations We reviewed systematic reviews and meta-analyses of randomized trials and clinical guidelines evaluating CGM use beyond type 1 diabetes, with particular attention to glycemic outcomes, hypoglycemia, patient-reported outcomes, and potential unintended consequences in nonpregnant adults. In adults with type 2 diabetes, evidence from randomized trials consistently demonstrated that CGM use was associated, on average, with a modest yet consistent reduction in hemoglobin A 1c of approximately 0.3% compared with finger-stick monitoring or usual care; some patients benefited considerably more. Only limited and indirect evidence supported the adoption of CGM in people with type 2 diabetes not receiving glucose-lowering therapy or in those with prediabetes or obesity. Conclusions and Relevance CGM should be deployed in response to a specific patient problem rather than as a default intervention. Deliberate, equitable deployment of CGM that is aligned with patient goals, clinical context, and system capacity will be necessary to ensure that those most likely to benefit are not left behind, while avoiding overuse in populations for whom benefit remains unproven.
Addition of High-Dose Vitamin D
3
to Standard Treatment in Patients With Metastatic Colorectal Cancer
Importance In a phase 2 randomized clinical trial, high-dose vitamin D 3 added to standard treatment improved progression-free survival (PFS) compared with standard-dose vitamin D 3 in patients with metastatic colorectal cancer (mCRC). Objective To determine if high-dose vitamin D 3 added to standard chemotherapy improves outcomes in patients with previously untreated mCRC. Design, Setting, and Participants Double-blind phase 3 randomized clinical trial enrolling 455 patients with previously untreated mCRC, conducted in the US through the National Clinical Trials Network from October 2019 to December 2022 (database freeze: July 15, 2024). Interventions mFOLFOX6 (modified FOLFOX6 [5-fluorouracil, leucovorin, oxaliplatin]) or FOLFIRI (5-fluorouracil, leucovorin, irinotecan) plus bevacizumab every 2 weeks with either high-dose vitamin D 3 (8000 IU daily × 14 days as loading dose followed by 4000 IU daily) or standard-dose vitamin D 3 (400 IU daily) until disease progression, intolerable toxicity, or withdrawal of consent. Main Outcomes and Measures The primary end point was PFS assessed by the unstratified log-rank test. Secondary end points included objective response rate, overall survival, and toxicity. Prespecified subgroup analyses of PFS were performed according to known prognostic factors. Results Among 455 randomized patients (median age, 59 years; 181 [40%] female) with median follow-up 20 months, the median PFS for high-dose vitamin D 3 (n = 228) was 11.8 months (95% CI, 10.3-13.3) vs 10.3 months (95% CI, 9.4-12.2) for standard-dose vitamin D 3 (n = 227) (1-sided log-rank P = .25). There were no significant differences in objective response rate between high-dose and standard-dose vitamin D 3 (51% [95% CI, 44%-58%] vs 44% [95% CI, 37%-50%], respectively; P = .12), or in overall survival (median, 25.6 vs 27.0 months; 1-sided log-rank P = .66). There were no clinically meaningful differences in the most common grade 3 or greater adverse events between the high- and standard-dose groups, including neutropenia (n = 67 [32%] vs n = 62 [30%]) and hypertension (n = 42 [20%] vs n = 49 [23%]) or in incidence of vitamin D–associated toxicities. Conclusions and Relevance Among patients with previously untreated mCRC, addition of high-dose vitamin D 3 , vs standard-dose vitamin D 3 , to standard chemotherapy plus bevacizumab did not improve PFS. Trial Registration ClinicalTrials.gov Identifier: NCT04094688
Circulating tumor DNA in colorectal cancer: assay selection, clinical applications, and practical integration for gastroenterologists
Background Circulating tumor DNA (ctDNA) has rapidly evolved from a research tool to a clinically applicable biomarker in colorectal cancer (CRC), transforming the assessment of minimal residual disease (MRD) and recurrence risk. The growing availability of commercial assays has complicated test selection and interpretation, particularly for gastroenterologists who increasingly encounter ctDNA data in postoperative and surveillance settings. Methods We conducted a narrative review of the literature using PubMed, Embase, and Cochrane databases from January 2015 through March 2026, prioritizing randomized controlled trials, prospective cohort studies, and clinical practice guidelines relevant to ctDNA applications in CRC. The search employed predefined keyword combinations applied independently to each database. Two authors (A.S. and S.M.) independently screened titles and abstracts against the prespecified inclusion criteria, with disagreements resolved by discussion. Results Tumor-informed assays that analyze patient-specific mutations exhibit high specificity for MRD detection, with serial sampling sensitivity reaching 88% compared to 59% for tumor-agnostic approaches, based on a 2026 systematic review and diagnostic accuracy meta-analysis that pooled data across multiple platforms and settings; the authors note substantial study-level heterogeneity in platform design and patient populations, and results should be interpreted accordingly, but require tissue access and extended processing times. Tumor-agnostic tests are more rapid and accessible, incorporating genomic and epigenomic signals, though they exhibit site-specific sensitivity variations ranging from 100% for liver metastases to 40% for peritoneal recurrence and remain vulnerable to biological confounders such as clonal hematopoiesis (CH). Importantly, ctDNA interpretation is subject to additional biological limitations including tumor shedding variability by anatomical site and disease burden, the timing of sample collection relative to surgery or chemotherapy, platform-specific detection thresholds, and pre-analytical variables such as hemolysis and delayed plasma processing. Randomized evidence supports ctDNA-guided de-escalation of adjuvant therapy in stage II colon cancer, with 5-year follow-up from the DYNAMIC trial demonstrating comparable recurrence-free survival (88% vs. 87%) and overall survival (93.8% vs. 93.3%) despite reduced chemotherapy use. In stage III disease, ctDNA is strongly prognostic, but chemotherapy intensification based solely on molecular positivity has not improved outcomes. This review additionally addresses underexplored areas including ctDNA in rectal cancer and neoadjuvant therapy, the influence of microsatellite instability (MSI) status on assay performance, and disparities in ctDNA access across racial, socioeconomic, and geographic populations. Conclusions For gastroenterologists encountering ctDNA results in postoperative and surveillance settings, three principles should guide practice (i): match assay selection to clinical intent - tumor-informed platforms for MRD-directed adjuvant decisions, tumor-agnostic platforms when tissue is unavailable (ii); interpret results within biological and technical context, accounting for platform-specific sensitivity limitations, biological confounders, and quantitative VAF trajectory rather than binary thresholds; and (iii) integrate ctDNA findings into multidisciplinary pathways - de-escalation is supported by high-quality randomized evidence in stage II disease (Grade A; Level I), while chemotherapy escalation based solely on ctDNA positivity in stage III disease is not supported outside clinical trials (Grade C; Level I). Standardization of assay performance benchmarks and equitable access to testing remain critical unmet needs.
ABSTRACT The recent inclusion of the Merlin clinicopathologic–gene expression profile (CP‐GEP) assay in the National Comprehensive Cancer Network (NCCN) Melanoma Guidelines represents an important milestone in the clinical integration of molecular testing for cutaneous melanoma. Unlike earlier melanoma gene expression profile (GEP) assays, which focused primarily on prognostic risk stratification, CP‐GEP was specifically developed to predict sentinel lymph node (SLN) metastasis risk by identifying early metastatic competence within primary melanomas, with additional prognostic utility. This review discusses the biological evidence supporting CP‐GEP and examines how unbiased transcriptomic discovery converged with established insights from cancer cell biology, integrin signaling, focal adhesions, and extracellular matrix (ECM) remodeling to shape its conceptual framework. We further discuss how CP‐GEP captures a transformation‐associated biological state centered on an integrin‐ and TGF‐β–dependent signaling axis ( ITGB3 , TGFBR1 ) that promotes pericellular proteolysis and ECM remodeling ( PLAT , SERPINE2 , LOXL4 ), inflammatory and angiogenic signaling ( CXCL8 , GDF15 ), and melanocytic lineage identity ( MLANA ). Collectively, these genes identify a dissemination‐competent phenotype that is detectable within primary tumors before clinically apparent metastasis. Overall, the biological framework supporting CP‐GEP reinforces the concept that altered adhesion signaling and ECM remodeling are central drivers of early melanoma metastasis and represent clinically actionable biomarkers for individualized melanoma management. image
Small-Data Deep Learning for Alzheimer-Spectrum Classification from Structural MRI: A Feasibility Study Using OASIS
Accurate estimation of Alzheimer’s disease (AD) severity from structural magnetic resonance imaging (MRI) remains difficult, as disease-associated anatomical alterations are often subtle and publicly available datasets are typically too small to support robust deep learning model training. This feasibility study sought to determine how much Alzheimer’s disease spectrum-related information could be extracted from a small structural MRI cohort using a deliberately lightweight two-dimensional convolutional neural network (2D CNN), and whether transfer learning improves model performance. This study was intended as a methodological proof of concept rather than the development of a clinically deployable diagnostic tool. Structural scans and Clinical Dementia Rating (CDR) labels from the OASIS-1 dataset were filtered to 214 subjects: 124 cognitively normal (CN), 65 with mild cognitive impairment (MCI; CDR = 0.5), and 25 with AD-level impairment (CDR ≥ 1). A compact 2D CNN trained from scratch and a transfer learning model (frozen ImageNet MobileNetV2 features) were evaluated on four binary tasks (CN vs. AD, MCI vs. AD, CN vs. MCI, and CN vs. any impairment) under identical pre-processing and subject-level repeated 5-fold cross-validation (10 repeats), with the decision threshold tuned only on an inner split. Discrimination was summarized by ROC-AUC with 95% confidence intervals (CIs), permutation tests against chance, and per-task sensitivity and specificity. The from-scratch CNN recovered only a broad normal-versus-impaired signal (CN vs. any impairment AUC 0.59) and was at chance on adjacent-stage tasks (MCI vs. AD 0.41; CN vs. MCI 0.51). Transfer learning improved every task: CN vs. AD AUC 0.745 (95% CI 0.730–0.763), CN vs. any impairment 0.642, CN vs. MCI 0.601, and MCI vs. AD 0.599. On an independent OASIS-2 cohort, the transfer learning CN vs. AD model retained AUC 0.748. In this small-data regime, transfer learning recovers substantially more Alzheimer-spectrum signals than a from-scratch CNN, but performance remains modest because it is bounded by CDR-based, non-biomarker-confirmed labels, suggesting the model separates CDR-defined cognitive-status groups rather than detecting AD pathology.