Protopine (52) suppressed dose–dependently the proliferation of colon cancer HCT116 cells, activated caspase 3/7 (CASP3/7), which subsequently catalyzed poly ADP–ribose polymerase (PARP) cleavage and increased the number of annexin V–FITC–positive cells. This evidence concerns the gene CASP3 and colonic neoplasm.