Fig. 5: Proteasome inhibitors induce endogenous ChaC1 and enhance AUR-induced cell death in HCC cells.

A Huh7 cells were treated with 50 nM BTZ, 100 nM IXZ, 100 nM DLZ or 100 nM CFZ for 12 h. The protein expression levels of ChaC1, ATF4, ATF3 and Nrf2 were determined by western blotting. B, C ATF4 knockout Huh7 cells and their control cells were treated with BTZ, IXZ, DLZ or CFZ for 12 h. The mRNA levels of ChaC1 were measured by qRT-PCR (B). The protein expression levels of ChaC1, ATF4 and Nrf2 were determined by western blotting (C). D, E Hep3B (D) and PLC/PRF/5 (E) cells were treated with BTZ, IXZ, DLZ or CFZ for 12 h. The expression levels of ChaC1, ATF4 and ATF3 were measured by western blotting. F Huh7 cells were treated with 1 µM AUR with or without BTZ, IXZ, DLZ or CFZ for 12 h. The expression levels of DDIT4, ChaC1, ATF4, ATF3 and Nrf2 were determined by western blotting.