ACTA1 and cancer: We next studied CAF migration by tracing cell motility owing to the following reasons: 1) TGF‐β is a potent growth factor for fibroblasts by stimulating cell proliferation and migration; 2) α‐SMA positive signals that represented myofibroblasts are markedly increased in Bmal1−/− CAFs, which should be highly motile; 3) CAF motility is highly associated with cancer metastasis.[28] Expectedly, Bmal1−/− CAFs exhibited increased motility relative to Bmal1+/+ CAFs (Figure 3D), supporting a myofibroblast phenotype.