After transient transfection with Hint1 by plasmids, human SW480 colon cancer cells and human MCF-7 breast carcinoma cells underwent apoptosis as analyzed by the expression of pro-caspase-3 and poly (ADP-ribose) polymerase cleavage (Weiske and Huber, 2006). The gene discussed is HINT1; the disease is malignant colon neoplasm.