IGF1 and neoplasm: The ability of proliferation, migration and formation of tube-like structures of HUVECs is significantly enhanced in tumor-conditioned medium (TCM) of CD147-expressing SMMC-7721 cells with IGF-I, but when IGF-I is removed from TCM or the cells are transfected with specific CD147 siRNA, the inductive effect on HUVECs is decreased [18].