TGFB1 and neoplasm: High-resolution atomic force microscopy (hrAFM) has demonstrated TGF-β1 and COMP complexes containing one to three COMP and multiple TGF-β1 molecules; such multivalent presentation of growth factors may explain COMP’s unique properties in growth factor presentation and the activation of receptors operative in chondrogenesis, osteogenesis, tissue fibrosis and tumor biology [32,33,34,35,36,37,38].