PDGFRB and cholangiocarcinoma: To determine whether targeting the PDGF-BB/PDGFR paracrine signaling axis could inhibit tumor growth and LNM, we first assessed the effects of PDGF-BB blocking antibodies and the PDGFR inhibitor STI571 on CCA cell migration, invasion, TrEM, and clonal formation, as well as on HLEC migration and lymph vessel formation induced by CAF supernatants.