ACTA1 and neoplasm: We observed that ADAM12+ MSCs (expressing GFP) localized specifically at the tumor margin, a transition zone enriched in stromal cells expressing various levels of PDPN and smooth muscle actin alpha 2 (αSMA+), collagenous ECM, T cells, CD206+ TAMs and blood vessels (Fig. 1a,b and Extended Data Fig. 1a,b).