Indeed, reciprocal crosstalk between CAFs (and other immune cells in CCA) promotes tumor progression, tissue invasion and metastasis by stimulating the expression of inflammatory and pro-tumorigenic factors, immunosuppressive cytokines and the activation of stemness pathways [39], the latter likely through the 5-LO/LTB4-BLT2 axis and TGF-β signaling [30,31,32,33,34,35,36,37,38,39,40]. Here, TGFB1 is linked to cholangiocarcinoma.