ACTA2 and cancer: Pericytes/smooth muscle cells, important regulators of angiogenesis and vascular integrity expressed ACTA2/α-SMA, COL4A1, and MYH11 (Supplementary Fig. 5.2c, Supplementary Table S14), markers previously implicated in T-cell exclusion by cancer-associated fibroblasts (CAFs) in early-stage lung adenocarcinoma89.