TGFB1 and colorectal carcinoma: Furthermore, Nodal, which is a TGF-β superfamily member, critical for endomesodermal induction, is associated with α-smooth muscle actin (α-SMA) positive expression in CRC tissues and contributes to the transition of resident fibroblasts into CAFs through the activation of TGF-β/Smad/Snail pathway [14].