TGFB1 and neoplasm: Although the tumor-associated macrophages by themselves are not the active producers of ECM components, these stromal cells secrete TGFβ and FGF and hence participate in the TGFβ- and FGF-mediated recruitment, proliferation, and functional stimulation of CAFs being the ECM-producers; this is the indirect involvement of stromal macrophages in the overproduction of intratumoral ECM.