Background: Muscle-invasive bladder cancer (MIBC) is a highly aggressive disease with a poor prognosis. B cells are crucial factors in tumor suppression, and tertiary lymphoid structures (TLSs) facilitate immune cell recruitment to the tumor microenvironment (TME). However, the function and mechanisms of tumor-infiltrating B cells and TLSs in MIBC need to be explored further. Methods: We performed single-cell RNA sequencing analysis of 11,612 B cells and 55,392 T cells from 12 bladder cancer patients and found naïve B cells, proliferating B cells, plasma cells, interferon-stimulated B cells and germinal center-associated B cells, and described the phenotype, gene enrichment, cell–cell communication, biological processes. We utilized immunohistochemistry (IHC) and immunofluorescence (IF) to describe TLSs morphology in MIBC. Results: The interferon-stimulated B-cell subtype (B-ISG15) and germinal center-associated B-cell subtypes (B-LMO2, B-STMN1) were significantly enriched in MIBC. TLSs in MIBC exhibited a distinct follicular structure characterized by a central region of B cells resembling a germinal center surrounded by T cells. CellChat analysis showed that CXCL13 + T cells play a pivotal role in recruiting CXCR5 + B cells. Cell migration experiments demonstrated the chemoattraction of CXCL13 toward CXCR5 + B cells. Importantly, the infiltration of the interferon-stimulated B-cell subtype and the presence of TLSs correlated with a more favorable prognosis in MIBC. Conclusions: The study revealed the heterogeneity of B-cell subtypes in MIBC and suggests a pivotal role of TLSs in MIBC outcomes. Our study provides novel insights that contribute to the precision treatment of MIBC.

Muscle-invasive bladder cancer (MIBC) is characterized by a complex tumor microenvironment (TME) that drives aggressive progression and treatment resistance. Previous studies have highlighted the roles of cancer-associated fibroblasts (CAFs) and exhausted T (Tex) cells in MIBC, but their interactive mechanisms remain poorly understood. Here, single-cell RNA sequencing of 19 tissue samples from 12 patients—7 MIBC, 3 non-muscle-invasive bladder cancer (NMIBC), and 9 normal tissue samples—identified 13 transcriptionally distinct fibroblast clusters and 10 functionally heterogeneous T-cell subsets. Two interferon (IFN)-responsive fibroblast populations, F-ISG15 (inflammatory CAFs) and F-POSTN (myofibroblastic CAFs), were shown to predominate in the MIBC TME. In vivo experiments demonstrated that IFN-γ secreted by Tex cells polarizes CAFs to secrete CXCL12, which recruits CXCR4-expressing T cells via the CXCL12-CXCR4 chemotactic axis. Spatial analysis revealed a bidirectional loop: Tex-derived IFN-γ sustains CAF activation, whereas CAF-secreted CXCL12 amplifies Tex infiltration. Clinically, activated CAF signatures correlate with advanced disease stages and reduced patient survival in MIBC. These findings establish CXCL12 and IFN signaling as critical therapeutic targets, offering new strategies to disrupt immunosuppressive TME crosstalk and improve outcomes for MIBC patients.

Objective: Idiopathic membranous nephropathy (IMN) is a leading cause of nephrotic syndrome in middle-aged and elderly populations. Early intervention can delay disease progression and improve patient outcomes. This study aims to identify urinary biomarkers for IMN and investigate their association with disease progression, offering new insights for precise diagnosis and treatment.Methods: This study began with RNA sequencing of three urine sample types (first-void morning urine, second-void morning urine, and random urine), combined with single-cell RNA sequencing of renal tissues. Bioinformatics analyses—including differential gene expression screening, machine learning, and molecular function annotation—were employed to identify potential IMN biomarkers. Furthermore, we established both a siRNA-mediated gene silencing model and a lentivirus transfection-mediated gene overexpression model in HK-2 cells. Subsequently, we investigated the functional mechanisms of the candidate biomarkers through qRT-PCR, Western blot, immunohistochemistry, and immunofluorescence assays.Results: SPP1 was identified as a promising biomarker for IMN, demonstrating a critical role in promoting fibrosis and inflammatory responses associated with the disease. These findings suggest its potential as a novel therapeutic target for IMN intervention.

Objective: Idiopathic membranous nephropathy (IMN) is the leading cause of nephrotic syndrome in adults. Given the limited diagnostic options currently available, we performed RNA sequencing (RNA-seq) of urinary cells to identify potential urinary biomarkers for IMN and to investigate its underlying disease mechanisms.Methods: We conducted RNA-seq analysis on cells isolated from both first-void and second-void morning urine samples. By integrating these data with single-cell RNA sequencing (scRNA-seq) data from IMN and healthy kidney tissues, we performed comprehensive analyses including: Inflammatory index assessment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, Gene Ontology (GO) functional annotation, Gene Set Enrichment Analysis (GSEA) enrichment analysis, Protein-Protein Interaction (PPI) network construction. Candidate differentially expressed genes (DEGs) were further validated using urinary cell RNA-seq data. Key genes were ultimately identified through Weighted Gene Co-expression Network Analysis (WGCNA) and subsequently verified by immunohistochemical and Quantitative Real-Time PCR (qRT-PCR) experiments of tissue expression patterns.Results: Our findings demonstrate that the CALR gene is significantly associated with IMN pathogenesis and progression. Functionally, CALR plays crucial roles in both immune response (particularly in antigen presentation) and physiological processes (notably in hemoglobin production).

Pyroptosis, a form of programmed cell death driven by the NLRP3 inflammasome, is a key contributor to inflammation in various diseases. This study aimed to investigate the anti-inflammatory mechanisms of cordycepin, focusing on its role in macrophage pyroptosis. Molecular docking analysis was performed to evaluate the binding affinity of cordycepin to key pyroptosis-related proteins, including NLRP3, Caspase-1, and GSDMD. RAW264.7 cells were pre-treated with cordycepin to assess its effects on pyroptosis. Key measurements included reactive oxygen species (ROS) levels, xanthine oxidase (XO) activity, and the expression of NLRP3, Caspase-1, and GSDMD. Additionally, lactate dehydrogenase (LDH) release, interleukin (IL)-1β and IL-18 levels in the culture supernatant, and macrophage cell death rates were evaluated using Hoechst 33342/PI dual staining. The results demonstrated that cordycepin exhibits strong binding affinity for NLRP3, Caspase-1, and GSDMD. Cordycepin pre-treatment significantly reduced ROS levels and XO activity, inhibited the expression of NLRP3, cleaved-Caspase-1, and cleaved-GSDMD, and decreased pyroptosis-associated inflammatory cytokines IL-1β and IL-18, along with Caspase-1 activity. Furthermore, cordycepin reduced the macrophage pyroptosis rate. In conclusion, cordycepin inhibits macrophage pyroptosis by reducing XO activity, suppressing ROS production, and regulating the expression of key molecules in the NLRP3/Caspase-1/GSDMD pathway. These findings provide a strong experimental basis for the potential development of cordycepin as a novel anti-inflammatory agent.

Objective: Investigating the interaction between Mast cells (MCs) and Mononuclear Phagocytes (MPs) in the tumor microenvironment (TME) of blader cancer (BCa) to uncover potential immunotherapeutic targets.