CASP3 and cancer: Interestingly, Jurkat cells co-cultured with MLN4924-pretreated cancer cells underwent apoptosis, although the effect is minor, as evidenced by minor increased levels of cleaved-PARP and cleaved caspase-3 (Figs. 4A and S5A), suggesting that PD-L1 induction by MLN4924 in cancer cells indeed triggers the killing of co-cultured Jurkat cells.