ACTA1 and colonic neoplasm: Interestingly, cultured α-SMA+ CAFs from colon tumor and melanoma carcinoma, as well as human fibroblast-specific 112 kDa surface molecule+(Thy1)α-SMA+FAP+ CAFs from lung cancer, have been reported to express immune checkpoint molecule programmed death 1 ligand 1/2(PDL-1 /2), which strongly induce T cell exhaustion [87–89].