Three broadly defined CAF subpopulations were first described in pancreatic ductal adenocarcinoma (PDAC) and referred to as myofibroblastic CAFs (myCAFs, high α-SMA), inflammatory CAFs (iCAFs, low α-SMA, and high inflammatory cytokines) and antigen-presenting CAFs (apCAFs, high MHC II–related genes)33. Here, ACTA1 is linked to pancreatic ductal adenocarcinoma.