PDGFRA and neoplasm: We then co-stained for PKMYT1, TGF-α, SFRP1 and SFRP2 with the fibroblast markers: Collagen IVα1, PDGFR-α and α-SMA, which were respectively associated with ECM remodeling, immune modulation/M2 polarization and tumor proliferation/immune suppression (12–14).