CASP3 and colonic neoplasm: To investigate whether thalidezine exhibits potent cytotoxic effects towards apoptosis-resistant cells, a panel of apoptosis-defective MEF cells (caspase 3, 7, 8 KO, 3/8 DKO, and Bax-Bak DKO) and DLD-1 BAX-BAK DKO colon cancer cells were used.