IGF1 and colorectal cancer: In vitro studies on human colon cancer cells showed cells proliferation promotion by IGF-I, an overexpression of IGF-IR, and inhibition of tumor cell growth using its monoclonal antibody [71]; moreover IGF-I serum levels are increased in patients with locally advanced colorectal cancer (pT3 and pT4), in comparison to less advanced (pT2) [72].