TGFB1 and neoplasm: TGFβ secreted by several cell types is a key external signal of EMT with a complex biphasic function of opposing effects depending on tumor microenvironment (Zavadil and Bottinger, 2005; Massague, 2012; Aykul and Martinez-Hackert, 2016; Derynck et al., 2021; Liu et al., 2021).