Expression of α smooth muscle actin (αSMA) is associated with subsets of “activated” (ie, profibrotic) fibroblasts in a variety of fibrotic pathologies and cancer types.38–40 Interestingly, in oral carcinoma, a subtype of CAFs with low αSMA expression was recently found to have an inhibitory effect on tumor proliferation and cancer cell self-renewal in vitro.41 Such results suggest a dual role for fibroblasts in tumors, with certain subpopulations encouraging tumor proliferation and other subpopulations involved in limiting it, both of which may be clinically targetable. Here, ACTA1 is linked to cancer.