In Vitro Effect of the Histone Deacetylase Inhibitor Valproic Acid on Viability and Apoptosis of the PLC/PRF5 Human Hepatocellular Carcinoma Cell Line

Abstract

The nucleosome is the fundamental building block of eukaryotic chromatin formed by DNA and histone proteins.<br />Chromatin modifications such as acetylation, methylation, and phosphorylation are necessary for protection,<br />replication, and gene transcription. Histone deacetylases (HDACs) are a group of enzymes that remove acetyl groups<br />to re-establish positive charges on histones and aberrant deacetylation may lead to tumorigenesis in different tissues.<br />Histone deacetylase inhibitors (HDACIs) are a class of chemotherapeutic agent that can reactivate gene expression<br />and inhibit the growth of tumor cells by histone deacetylase inhibition. HDACI valproic acid (VPA) has shown potent<br />anticancer effects in vitro and in vivo. Previously, we reported that VAP can inhibit the growth and induce apoptosis<br />of human colon carcinoma HT 29 and hepatocellular carcinoma HepG 2 cells. The aim of the present study was to<br />access the effect of VPA on proliferation and apoptosis of the human hepatocellular carcinoma (HCC) PLC/PRF5 cell<br />line. Materials and Methods: PLC/PRF5 cells were treated with VPA and then MTT and flow cytometry assays were<br />used to determine the effects on viability and apoptosis, respectively. Results: VPA inhibited cell growth and induced<br />apoptosis in PLC/PRF5 cells significantly. Discussion: Our results clearly demonstrated that VPA has inhibitory and<br />apoptotic effects. Conclusion: VPA can significantly inhibit the growth of HCC cells and play a significant role in<br />apoptosis induction.