Hoechst 33342-induced autophagy protected HeLa cells from caspase-independent cell death with the participation of ROS.

Zheng, Fang; Yang, Wen-Jun; Sun, Ke-Jing; Wan, Xiao-Mei; Man, Na; Wen, Long-Ping

Autophagy, an evolutionarily-conserved intracellular organelle and protein degradation process, may exhibit drastically different effects on cell survival depending on the particular environmental and culturing conditions. Hoechst 33342 (HO), a fluorescent dye widely used for staining DNA, has been reported to induce apoptosis in mammalian cells. Here we showed that, in addition to caspase-independent cell death, HO also induced autophagy in HeLa cells, as evidenced by the accumulation of autophagosomes, LC3 form conversion and LC3 puncta formation in a cell line stably expressing GFP-LC3. HO treatment led to generation of reactive oxygen species (ROS), and inhibition of ROS with N-acetyl- l-cysteine (NAC) abrogated both autophagy and caspase-independent cell death. Finally, autophagy played a protective role against caspase-independent cell death, as cell death induced by HO was enhanced under pharmacological and siRNA-mediated genetic inhibition of autophagy.

AUTOPHAGY; HELA cells; CASPASES; REACTIVE oxygen species; SPECIES; CELL death; HOECHST 33258

Free Radical Research, 2012, Vol 46, Issue 6, p740

1071-5762

Academic Journal

10.3109/10715762.2012.670701