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Xu Zhang

Publications and source records attributed to Xu Zhang.

9 recordsLinked to original sources
PubMed2026

Cooccurrence of Homologous Recombination Deficiency and Mismatch Repair Deficiency in Colorectal Cancer.

Homologous recombination deficiency (HRD) in colorectal cancer (CRC) remains largely unexplored. In contrast, mismatch repair deficiency (dMMR) occurs in ∼15% of patients with CRC. Although HRD and dMMR have historically been regarded as mutually exclusive, emerging evidence suggests that this mutual exclusivity may not be absolute. Here, we conducted a retrospective cohort study utilizing genomic and transcriptomic data to define HRD status in a Chinese dMMR CRC cohort (n = 99). Multiple machine learning approaches were employed to analyze the expression profiles of these tumors and to develop a classifier distinguishing HRD from homologous recombination proficiency (HRP) in dMMR CRCs. In the Chinese dMMR CRC cohort, 66% of tumors were classified as HRD. Compared with the HRP group, the HRD group had a significantly higher tumor mutational burden and better outcomes. The derived expression signature, comprising eight genes, successfully predicted HRD status in dMMR tumors with high accuracy in the training set (AUC = 0.88, Naïve Bayes) and the test set (AUC = 0.87). In this study, a subset of dMMR CRC tumors with co-occurring HRD was identified, which may have potential implications for patient stratification and the application of targeted therapies, such as PARP inhibitors, in this molecular subgroup.

colorectal cancer↗
PubMed2026

Methane and carbon dioxide emissions from wastewater treatment units linked to DOM stabilization and phosphonate-scavenging microbiomes.

Municipal wastewater treatment plants (WWTPs) are major engineered facilities for urban carbon removal, yet methane (CH4) formation and source mechanisms in downstream stages after aeration and biological nutrient removal remain poorly resolved. Process resolved monitoring at a full-scale WWTP showed that CH4 emissions were concentrated upstream, while measurable fluxes persisted in downstream sedimentation and denitrification units. Dissolved CH4 profiles showed strong attenuation of influent derived CH4 during upstream treatment, followed by a local increase after secondary clarification. Carbon dioxide (CO2) emissions peaked in the biochemical tank, consistent with rapid oxidation of labile organic carbon. Fluorescence and molecular analyses revealed a shift in dissolved organic matter (DOM) from protein like to more humic and processed molecules, while community assembly remained predominantly deterministic despite greater stochasticity in later stages. The C-P lyase catalytic core was enriched in these units, accompanied by higher phnJ transcript abundance, candidate organophosphonate features, and genomic potential. Together with BES insensitive CH4 formation in independent microcosms, these observations supported C-P lyase mediated organophosphonate utilization as a contributing pathway to local CH4 formation. Integrated evidence indicated that DOM stabilization, deterministic community filtering, potential succinate mediated cross feeding, and phosphonate scavenging jointly shaped this process. These findings show that advanced treatment units are not CH4 hotspots, but neither are they CH4 inactive zones; process resolved GHG assessments should therefore consider persistent local CH4 generation and its association with substrate restructuring and alternative phosphorus acquisition.

Dissolved organic matter↗
PubMed2026

Integrative genetic and transcriptomic analyses prioritize CDC16 as a candidate marker for gastric cancer.

BackgroundGastric cancer (GC) remains a major cause of cancer-related mortality, and biomarkers for early detection are needed.MethodsStomach and blood expression quantitative trait loci were integrated with two GC genome-wide association studies using Mendelian randomization (MR), Bayesian colocalization, and summary-data-based MR/heterogeneity in dependent instruments (SMR/HEIDI) testing. Bulk and single-cell transcriptomic analyses characterized candidate expression and lesion-associated patterns. CDC16 protein expression was evaluated by immunohistochemistry in 53 paired GC and non-neoplastic tissues, followed by paired and exploratory receiver operating characteristic analyses.ResultsMR prioritized PILRB, CDC16, and GABPB1-AS1; SMR/HEIDI provided complementary support, while colocalization for CDC16 and GABPB1-AS1 was suggestive and model-dependent. Bulk-tissue CDC16 abundance was higher in GC, but the modest TCGA-STAD tumor-normal difference (log2FC = 0.210, FDR = 0.019) was attenuated after proliferation adjustment (log2FC = -0.002, FDR = 0.987), indicating close coupling with proliferative activity. Single-cell analysis localized CDC16 predominantly to epithelial populations, and the proportion of CDC16-detectable epithelial cells increased across lesion categories (&#x3c1; = 0.735; permutation P = 0.031). CDC16 H-scores were higher in GC than in paired non-neoplastic tissues (161.15 &#xb1; 45.11 vs 102.15 &#xb1; 54.50; P < 0.001), with higher cancer-tissue scores in 41 of 53 cases. Exploratory AUC was 0.794 (95% CI, 0.704-0.874; sensitivity, 66.0%; specificity, 79.2%).ConclusionsConvergent genetic, transcriptomic, and protein-level evidence prioritizes CDC16 as a GC-associated candidate tissue marker whose expression is closely linked to proliferative activity. Prospective validation in independent cohorts, including appropriate disease controls and blood-based evaluation, is warranted.

Stomach Neoplasms↗
PubMed2026

Single-cell profiling of mitochondrial phenotyping-coupled mtDNA genotyping.

Simultaneously profiling mitochondrial DNA (mtDNA) heteroplasmy and phenotypic variability at the single-cell level remains a challenge due to the absence of integrated methods that map mitochondrial genotypes alongside their functional states. We introduce human single-cell mitochondrial phenotype-coupled mtDNA sequencing (scMPCDS), a platform that quantifies mtDNA mutations and heteroplasmy together with mitochondrial membrane potential and reactive oxygen species within individual cells. Unlike bulk sequencing or separate single-omics techniques, scMPCDS directly correlates mitochondrial genomic instability with functional outcomes. Using this approach, we demonstrate that DdCBE-mediated mtDNA editing induces cell-specific off-target mutations in the mitochondrial genome, which coincide with diverse phenotypic changes. Applying scMPCDS to HeLa cells and clear cell renal cell carcinoma tissues, we identify single-cell subpopulations exhibiting distinct mtDNA mutation burdens and altered bioenergetic profiles, implicating potential mitochondrial heterogeneity-driven tumor evolution. Overall, scMPCDS serves as a versatile tool to unravel mitochondrial genotype-phenotype relationships at the single-cell level in both normal and disease states, thereby advancing precise mitochondrial diagnostics and therapeutics.

Humans↗
PubMed2026

Bibliometric analysis of retinoblastoma research over the past decade.

BACKGROUND: Retinoblastoma (RB), the most prevalent primary intraocular malignancy in children, has emerged as a model disease for exploring the molecular underpinnings of pediatric cancer. Over the past decade, research in this field has accelerated, propelled by advances in genomics, diagnostic imaging, targeted therapies, and global scientific collaboration. METHODS: This study systematically retrieved RB-related publications from 2015 to 2024 using the Web of Science Core Collection. A total of 4990 articles were included. CiteSpace and VOSviewer were employed to perform bibliometric and visual analyses across multiple dimensions, including countries, institutions, authors, journals, and thematic evolution. RESULTS: The United States and China were identified as the leading contributors, jointly accounting for over 40.55% of all publications. US-based journals led in both publication volume and citation impact, underscoring their global influence. Cluster analysis revealed 4 major research domains: clinical diagnosis, treatment, and prognosis; molecular mechanisms and signaling pathways; gene and protein function studies; and research methodologies and experimental models. CONCLUSION: RB research is transitioning into an era of precision oncology, characterized by molecular subtyping, novel therapeutic targets, and individualized treatment approaches. While diagnostic and therapeutic outcomes have markedly improved in high-income countries, significant disparities persist in low- and middle-income regions due to limited access to early detection and comprehensive care. Future priorities should include the refinement of preclinical models, investigation of drug resistance mechanisms, and promotion of international collaboration to standardize diagnostic and therapeutic strategies. These efforts are critical to improving global outcomes for children with RB.

Retinoblastoma↗
PubMed2026

Single-nucleotide transcription start sites profiling via Nascent Strand-Specific RNA sequencing uncovers IFN-&#x3b3;-induced promoter dynamics.

Transcriptional regulation is a highly dynamic process in which nascent RNAs provide the most immediate readout of transcriptional activity. Precise mapping of transcription start sites (TSSs) is therefore critical for understanding promoter architecture and gene regulation, yet remains technically challenging. Here, we introduce Nascent Strand-Specific RNA sequencing (NSS-seq), a robust and streamlined method for genome-wide profiling of the capped 5' ends of nascent RNAs. By directly capturing transcription initiation events, NSS-seq overcomes the temporal delay inherent to conventional RNA-seq and enables time-resolved interrogation of transcriptional dynamics. Applied to interferon-&#x3b3; (IFN-&#x3b3;)-stimulation, NSS-seq uncovers previously unrecognized IFN-&#x3b3;-responsive genes and transient transcription factor activation patterns underlying interferon-mediated tumor-suppressive functions. Together, NSS-seq provides a cost-effective and technically accessible platform for dissecting promoter-level regulatory dynamics during cellular responses.

Promoter Regions, Genetic↗
PubMed2025

Cholesterol Metabolism-related Characteristics Predict Therapeutic Response and Survival in Esophageal Cancer.

INTRODUCTION: Cholesterol homeostasis has been identified as an essential downstream pathway of mutations in TP53. Esophageal cancer is one of the most prevalent malignancies exhibiting the mutation. OBJECTIVES: To explore the significance of cholesterol metabolism-related characteristics in tumor phenotype and treatment outcomes of esophageal cancer. METHODS: We established a cholesterol metabolism-related gene set (CMGs) and performed Lasso-Cox analysis to identify prognostic signatures. Nomogram-based risk scores and clinical stages afterwards were constructed and evaluated. We simultaneously identified two metabolic subtypes based on the distinct features of the CMGs. We annotated the functional and pathway characteristics of differentially expressed genes between the clusters and compared the differences in clinical and immune characteristics. Finally, we assessed the prognostic value of signatures in the GSE53625 and two clinical cohorts using whole-exon sequencing and multiplex immunofluorescence. RESULTS: Our study identified five cholesterol prognosis-related genes (CRGs) that demonstrated superior prognostic efficacy in the training set compared to clinical staging, validated in independent public databases and two clinical cohorts. According to the different expression patterns of the signatures, patients were divided into two subtypes. The C1 group demonstrated poorer overall survival, response to immunotherapy, and downregulation of the p53 pathway. In the immune correlation analysis, we found that the risk score based on 5-signature model was significantly positively correlated with the abundance of suppressive immune cells and the immune checkpoints. Finally, we explored the impact of expression and genomic polymorphism of the signatures on the prognosis at the pan-cancer level. CONCLUSIONS: Our findings underscore the distinct expression patterns of CRGs in esophageal cancer. These signatures are efficient to serve as prognostic indicators and assess the effectiveness of immunotherapy. They may also represent promising targets in other TP53 mutant malignancies.

Humans↗