GLI1 and colorectal adenocarcinoma: To elucidate the mechanism of p,p′-DDE in promoting colorectal adenocarcinoma cell proliferation, both Wnt/β-catenin and Hedgehog/Gli1 signalings were examined after cells treated with p,p′-DDE (10−10, 10−9 and 10−8 M) for 96 h.