@article{APS4522,
author = {Peng-xing He and Jie Zhang and Yong-sheng Che and Qiao-jun He and Yi Chen and Jian Ding},
title = {G226, a new epipolythiodioxopiperazine derivative, triggers DNA damage and apoptosis in human cancer cells in vitro via ROS generation},
journal = {Acta Pharmacologica Sinica},
volume = {35},
number = {12},
year = {2016},
keywords = {},
abstract = {Peng-xing HE1, #, Jie ZHANG3, #, Yong-sheng CHE2, Qiao-jun HE1, Yi CHEN3, *, Jian DING3, *
1Institute of Pharmacology and Toxicology, School of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China; 2Beijing Institute of Pharmacology & Toxicology, Beijing 100190, China; 3Division of Anti-tumor Pharmacology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
Aim: G226 is a novel derivative of epipolythiodioxopiperazines with potent inhibitory activity against cancer cells. Here, we sought to identify potential targets involved in the anti-cancer activity of G226.
Methods: Cell proliferation assay was conducted in a panel of 12 human cancer cell lines. The activities of topoisomerase I (Topo I) and Topo II were studied using supercoiled pBR322 DNA relaxation and kDNA decatenation assays. ROS production was assessed with probes DCFH-DA and H&E. Western blot analysis and flow cytometry were used to examine DNA damage, apoptosis and cell cycle changes.
Results: G226 displayed potent cytotoxicity in the 12 human cancer cell lines with a mean IC50 value of 92.7 nmol/L. This compound (1–100 µmol/L) selectively inhibited the activity of Topo II, and elevated the expression of phosphorylated-H2AX in a dose-dependent manner. In Topo II-deficient HL60/MX2 cells, however, G226-induced DNA damage, apoptosis and cytotoxicity were only partially reduced, suggesting that Topo II was not essential for the anti-tumor effects of G226. Furthermore, G226 (0.125–2 µmol/L) dose-dependently elevated the intracellular levels of H2O2 and O2¯ · in the cancer cells, and pretreatment with GSH, NAC or DTT not only blocked G226-induced intracellular accumulation of ROS, but also abrogated G226-mediated phosphorylation of H2AX, apoptosis and cytotoxicity.
Conclusion: G226-mediated ROS production contributes to the anti-cancer activity of this compound.
Keywords: G226; epipolythiodioxopiperazine; 11′-deoxyverticillin A; anti-cancer agent; Topo II; DNA damage; apoptosis; ROS; antioxidant
The project was supported by the National Natural Science Foundation of China (81273545) and the National Basic Research Program Grant of China (2013CB932503).
# These authors contributed equally to this work.
* To whom correspondence should be addressed.
E-mail jding@simm.ac.cn (Jian DING); ychen@simm.ac.cn (Yi CHEN)
Received 2014-05-15 Accepted 2014-08-29},
issn = {1745-7254}, url = {http://www.chinaphar.com/article/view/4522}
}