Using CD167a staining to outline metastatic cancer cells, and α-SMA to outline ASMCs, we identified prevalent metastatic foci localized within COL3-rich ASMCs from the T24-LungMet model (Fig. 4j–m), as well as the spontaneous lung metastatic model of human PDX (Fig. 4n–q). Here, ACTA1 is linked to cancer.