EtBr-induced selective degradation of mitochondria occurs via autophagy

Luo,Yan; Hu,Yide; Zhang,Minghui; Xiao,Yu; Song,Zongchang; Xu,Yu

doi:10.3892/or.2013.2590

EtBr-induced selective degradation of mitochondria occurs via autophagy

Authors:
- Yan Luo
- Yide Hu
- Minghui Zhang
- Yu Xiao
- Zongchang Song
- Yu Xu
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Affiliations: Department of Oncology, The Second Affiliated Hospital, Third Military Medical University, Chongqing 400037, P.R. China
Published online on: July 4, 2013 https://doi.org/10.3892/or.2013.2590
Pages: 1201-1208

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Abstract

Recent studies have implicated autophagy in numerous cellular responses to stress. During the establishment of human lung cancer cell lines without mitochondrial DNA, a significant depopulation of mitochondria occurred that was accompanied by the loss of the mitochondrial membrane potential. Notably, we observed autophagy in ethidium bromide (EtBr)-induced mitochondrial degradation. In the present study, we confirmed the involvement of autophagy in mitochondrial degradation after exposure to a low concentration of EtBr. Lung cancer cells undergoing mitochondrial autophagy exhibited a slower growth rate in vitro and in vivo. Furthermore, the degradation was mediated by the class III phosphatidylinositol 3-kinase (PI3K)-Beclin-1 complex. These findings indicate that autophagy is responsible for EtBr‑induced mitochondrial degradation via the PI3K‑Beclin-1 signaling pathway.

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