Diethyl (6-amino-9H-purin-9-yl) methylphosphonate induces apoptosis and cell cycle arrest in hepatocellular carcinoma BEL-7402 cells: Role of reactive oxygen species

Abstract

The primary purpose of this work was to study the mechanism of the anti-proliferation activity of compound diethyl (6-amino-9H-purin-9-yl) methylphosphonate (DaMP), a novel acyclic nucleoside phosphonate. Using cell survival MTT assay, flow cytometry analysis, DNA laddering, DCF fluorescence detection and caspases assays, this study investigated the effects of this compound on cell apoptosis, cell cycle regulation and reactive oxygen species in human hepatocarcinoma BEL-7402 cell lines. Exposure to DaMP at 80 μM for 24 h, BEL-7402 cells displayed a marked retardation of S-phase progression, leading to a severe perturbation of normal cell cycle. In addition, DaMP also significantly inhibited cell proliferation by inducing apoptosis, disrupting DNA synthesis and increasing the activities of caspase-3 and -9, while the antioxidants could significantly inhibit these effects. This study was the first to demonstrate that DaMP could induce apoptosis and cell cycle arrest by producing reactive oxygen species and activating caspase-3 and -9.

Keywords::

• Acyclic nucleoside phosphonate
• reactive oxygen species (ROS)
• oxidative stress
• apoptosis
• vitamin C

Acknowledgements

We thank Professor Yukun Yuan from Michigan State University, USA, Dr Alan Payne from Curtin University of Technology, Australia and Dr Philip E. Lyon from Troy University, USA for their critical reviews and corrections.

Declaration of interest: This work was supported by the Natural Science Foundation of Shandong Province (Y2008B32). The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

This paper was first published online on Early Online on 4 June 2010.