FSTL1 and pachyonychia congenita: In conclusion, our study successfully identified a module of six key genes—GFPT2, MFAP5, CTSK, MMP2, FSTL1, and PRRX1—through Weighted Gene Co-expression Network Analysis (WGCNA) to assess cancer-associated fibroblast (CAF) infiltration in pancreatic cancer (PC).