Importantly, induction of autophagy through ATF4 has been proposed as a relevant resistance mechanism to Bortezomib treatment in breast cancer cells40 and we have previously reported strong up-regulation of ATF4, and mostly CHOP, in MCF7 but not in MCF10A cells, 24 hours after proteasome inhibition24. The gene discussed is DDIT3; the disease is breast carcinoma.