Cancer-associated fibroblast-derived MMP11 promotes tumor progression in pancreatic cancer

Matrix metalloproteinase 11 (MMP11), a zinc-dependent endopeptidase involved in extracellular matrix degradation and remodeling, has been identified as a tumor promoter in multiple cancer types. However, its expression pattern and role in pancreatic ductal adenocarcinoma (PDAC) remain unclear. In this study, elevated MMP11 expression was identified in PDAC tissues and was associated with diminished survival. Integrated single-cell RNA sequencing and co-immunofluorescence staining revealed that MMP11 was predominantly expressed in cancer-associated fibroblasts (CAFs). Mechanistically, cancer cell-derived TGF-β1 mediated CAF activation via the pSmad2/3 pathway and accompanied by MMP11 production. Additionally, MMP11 knockdown in CAFs impaired the proliferative and invasive abilities of AsPC-1 and BxPC-3 cells in vitro; which could be rescued by adding recombinant MMP11. Similarly, co-injection of AsPC-1 cells with MMP11-knockdown CAFs into nude mice significantly suppressed tumor growth and liver metastasis compared with tumors bearing unmodified CAFs. Furthermore, we confirmed that CAF-derived MMP11 may drive the epithelial-mesenchymal transition process of PDAC cells to promote tumor invasion via the PI3K/AKT pathway rather than extracellular matrix remodeling. Collectively, we uncovered a crosstalk between cancer cells and CAFs mediated by TGF-β1 and MMP11 that drives the progression of PDAC.