CASP8 and colonic neoplasm: Conversely, depletion of DR5 using siRNA transfection reduced significant cytotoxicity by EGCG and TRAIL co-treatment in in SW480 and HCT116 cells and also blocked the apoptotic effects of EGCG and TRAIL co-treatment to increase sub-G1 population and PARP cleavages in SW480 cells, indicating that EGCG sensitizes colon cancer cells to TRAIL mediated apoptosis via activation of caspase 8 and upregulation of DR5.