Differential induction of autophagy in caspase-3/7 down-regulating and Bcl-2 overexpressing recombinant CHO cells subjected to sodium butyrate treatment

Previous research showed that co-down-regulation of caspase-3/7 in rCHO cells, unlike Bcl-2 overexpression, did not effectively block apoptotic cell death induced by 3 mM sodium butyrate (NaBu). Here, it is found that the control of autophagy is also related to this different response to NaBu treatment. With NaBu treatment, co-down-regulation of caspase-3/7 enhanced autophagy induction, whereas Bcl-2 overexpression delayed onset of autophagy induction in a Beclin-1 independent manner. The blockage of autophagy showed a detrimental effect on cell viability even in the Bcl-2 overexpressing cells, which suggests the importance of autophagy control for successful anti-cell death engineering of rCHO cells.

► Caspase-3/7 down-regulation did not inhibit NaBu-induced cell death in rCHO cells.
► Bcl-2 overexpression inhibited NaBu-induced cell death in rCHO cells effectively.
► Caspase-3/7 down-regulation enhanced autophagy induction upon NaBu treatment.
► Bcl-2 overexpression delayed onset of autophagy induction upon NaBu treatment.
► The blockage of autophagy decreased viability in the Bcl-2 overexpressing cells.