Abstract
The immune microenvironment and prognosis of bladder cancer (BLCA) remain ongoing challenges in its treatment. This study aimed to establish predictive prognostic indicators and investigate the immune microenvironment to enhance clinical treatment strategies. A single-cell transcriptional atlas was constructed using single-cell RNA-seq data from patients with bladder cancer, focusing on fibroblast-related gene expression, intercellular communication, metabolic pathways inferred by single-cell flux estimation analysis, and transcription factor networks. Fibroblast-associated prognostic gene signatures were validated using data from The Cancer Genome Atlas, and a prognostic model was developed to stratify patients with bladder cancer into high- and low-risk groups. Analysis of three para-carcinoma single-cell samples revealed the presence of 3,603 fibroblasts and 500 fibroblast-associated marker genes. Notably, key fibroblast-specific transcription factors, including MAF, TWIST1, and TCF21, were identified through SCENIC analysis. The incorporation of comprehensive RNA sequencing data enabled the discovery of prognostic markers associated with fibroblasts. Using this classification model, patient survival could be stratified into high- and low-risk categories based on the model. The results of our study highlight the prognostic genetic signatures associated with the fibroblast component of the immune microenvironment in BLCA, offering preliminary insights into prognostic assessment and potential therapeutic implications.
Data availability
RNA sequencing data used in this study are available in the Gene Expression Omnibus (GEO) under accession code GSE129845.
Abbreviations
- BLCA:
-
Bladder cancer
- TME:
-
Tumour microenvironment
- CAFs:
-
Cancer-associated fibroblasts
- TCGA:
-
The Cancer Genome Atlas
- GEO:
-
Gene Expression Omnibus
- PCA:
-
Principal component analysis
- DEGs:
-
Differentially expressed genes
- GO:
-
Gene ontology
- GRNs:
-
Genetic regulatory networks
- RAS:
-
Regulon activity score
- SEEK:
-
Search-based exploration of expression
- LASSO:
-
Least absolute shrinkage and selection operator
- GC:
-
Gastric cancer
- ROC:
-
Receiver operating characteristic
- MAF:
-
Mutation annotation format
- TMB:
-
Tumor mutation burden
- GTEx:
-
Genotype-tissue expression
- scFEA:
-
Single-cell flux estimation analysis
- EMT:
-
Epithelial-mesenchymal transition
- ECM:
-
Extracellular matrix
- TGF-β:
-
Transforming growth factor-beta
- BMPs:
-
Bone morphogenetic proteins
- AUC:
-
Area under the curve
- FBN1:
-
Fibrillin-1
- PID1 :
-
Phosphotyrosine interaction domain-containing 1
- PRELP :
-
Proline/arginine-rich end leucine-rich repeat protein
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Acknowledgements
We thank the funding support. And thank all of the authors participate in the study and the time that they devoted to the study.
Funding
This work was supported by grants from the Natural Science Foundation of Hubei Province (2025AFD054), Shiyan Municipal Science and Technology Bureau Project (25Y132), and Innovative Research Program for Graduates of Basic Medical College, Hubei University of Medicine (NO. JC2024007).
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Conceptualization: Yan Tan, Lei Xi and Peng Duan; Data curation: Xiaojuan Tang and Ling Liu; Methodology: Xiaojuan Tang, Ling Liu and Min Gao; Funding acquisition: Peng Duan and Lei Xi; Formal analysis and investigation: Xiaojuan Tang, Lei Xi and Sheng Li; Project administration: Yan Tan and Peng Duan; Writing original draft: Xiaojuan Tang and Ling Liu; Writing – review & editing: Min Gao, Lei Xi, Sheng Li, Zilong Yuan and Qiang Xia; All authors read and approved the final manuscript.
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All procedures were performed in compliance with relevant laws and institutional guidelines and have been approved by the Professional Committee of Scientific Research and Academic Ethics of Shiyan People’s Hospital, consent was obtained for experimentation with human subjects. The date and reference number of the ethical approval(s) obtained: May 19, 2025; SYRMYY-2025-059.
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Tang, X., Liu, L., Gao, M. et al. Single-cell transcriptomics identifies fibroblast associated immune heterogeneity and prognostic signatures in bladder cancer. Sci Rep (2026). https://doi.org/10.1038/s41598-026-38219-x
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DOI: https://doi.org/10.1038/s41598-026-38219-x