The most established CAF classification in PDAC was proposed by Tuveson et al., who categorized CAFs into three subsets: myofibroblastic CAFs (myCAFs), which robustly express α-smooth muscle actin (α-SMA); inflammatory CAFs (iCAFs), which produce inflammatory cytokines such as interleukin (IL)-6; and antigen-presenting CAFs (apCAFs), which have recently displayed the potential to induce regulatory T cells and suppress anti-tumor immunity [22,23,24] (Figure 2). Here, ACTA1 is linked to neoplasm.