To verify the binding of miR-455 to 3 ‘-UTR of GREM1 mRNA, we co-transfected miR-455 mimic with GREM1 wild-type 3’-UTR or GREM1 mutant 3’-UTR in human colorectal cancer cells, and then measured and calculated luciferase ability. The gene discussed is GREM1; the disease is colorectal cancer.