CASP3 and colorectal carcinoma: TRAIL addition to cultures of SW620 CRC cells shows an IC50 value of 423.5 ng/mL, whereas this parameter is reduced to only 121.1 ng/mL in the presence of 2 μM celastrol during 72 h, due to apoptosis induction via caspase 3; therefore, celastrol shows a synergistic effect in combination with TRAIL (Zhu et al., 2010).