GEOapplication/xmlftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE318nnn/GSE318657/primaryOK200TranscriptomicsHomo sapiensExpression profiling by high throughput sequencinghttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE318657GEOGSEfalseIntegrated Single-Cell, Proteomic, and Tissue-Level Analysis Defines Cancer-Associated Fibroblast Programs in Pseudomyxoma PeritoneiPseudomyxoma peritonei (PMP) is an ultra-rare mucinous neoplasm with extensive stromal remodeling, yet the role of cancer-associated fibroblasts (CAFs) remains poorly defined. CAF are abundantly present in fibrous septae containing the mucin and regions of inflammation. We established PMP-derived CAF cultures and characterized them through multiple omics and phenotypic assays. Single-cell transcriptomic profiling revealed two distinct CAF populations: fibroblast-derived CAFs enriched for characteristic CAF functionalities and mesothelial-derived CAFs expressing mesothelial markers and pathways linked to metabolism and motility, consistent with mesothelial-to-mesenchymal transition. PMP CAFs exhibit baseline invasive and contractile properties and acquire an inflammatory CAF-like phenotype upon TNF-α/IL-1β stimulation, accompanied by altered proteomic and secretome profiles. Conditioned media from PMP CAFs further promoted macrophage polarization, highlighting their role in shaping the immune microenvironment. In conclusion, our findings reveal a previously uncharacterized role for CAF in PMP, highlighting their contribution to immune modulation in this extremely scarce peritoneal malignancy.2026/07/03GSE318657GSM950004624676318657Homo sapiens