Effect of Dioscorea extract on Bax and Bcl-2 gene expression in MCF-7 and HFF cell lines

Abstract

BackgroundIn cancer cells, the balance between proliferation and apoptosis is disturbed. There is a direct relationship between gene expression and the process of apoptosis. The two genes involved in apoptosis are Bax and Bcl-2, and it is now well established that some plant compounds can alter the expression of genes. The aim of this study is to determine the rate of change in the expression of these genes in the cell line MCF-7 treated with Dioscorea extract for 24, 48 and 72 h. For this purpose, the plant extract was prepared by Soxhlet method and diluted in different concentrations. MCF-7 and HFF cell lines were treated in three replicates with different concentrations of the extract at intervals of 24, 48, and 72 h. To evaluate the toxicity of the extract, the MTT assay was performed and the IC50 value was calculated. Both cell types were cultured at IC50 concentration with three treatments and three replicates. RNA extraction, cDNA synthesis and real-time PCR were then performed. Flow cytometry was performed to further confirm apoptosis.ResultsMTT results showed that 72 h treatment with Dioscorea extract in IC50 concentration had the greatest effect on the death of MCF-7 cancer cells, while the cells of the control cell line remained healthy. The results of the study of gene expression changes showed that when treated with the plant extract for 24 h, the increase in Bax gene expression and the decrease in Bcl-2 gene expression were not statistically significant. At 48-h treatment, the decrease in Bcl-2 expression was not statistically significant, whereas the increase in Bax expression, which was 2.1 times, was statistically significant. When treated with the plant extract for 72 h, Bax expression increased 2.72 times and Bcl-2 gene expression decreased 0.67 times. Flow cytometry showed that 72-h treatment with plant extract at a concentration of 438.35 µg/ml was the most effective treatment for MCF-7 cancer cell death.ConclusionsThe expression ratio of Bax gene to Bcl-2 is equal to 4.06, which indicates the induction of more apoptosis by treatment with plant extract.