Effects of Epigallocatechin-3-galate on growth inhibition of Reh cell line and methylation of RUNX3 gene

Abstract

Abstract: AIM: To investigate the effects of epigallocatechin-3-gallate on the proliferation and the methylation status of Reh cells,and to explore the mechanism of the silencing of tumor suppressor gene RUNX3 and the regulating effect of EGCG on RUNX3 gene expression. METHODS: The cultured Reh cells were incubated with EGCG for different concentrations of 5, 10, 15 and 20 μg/mL, MTT assay was used to analyse the inhibition of cell proliferation by EGCG, cell apoptosis index was examined by flow cytometry, methylation-specific PCR (MSP) analysis was evaluated for the promoter region methylation status of the RUNX3 gene in Reh cell line. The mRNA and protein level of RUNX3 was detected by RT-PCR and western blot. RESULTS: EGCG of different concentrations could significantly inhibit proliferation and increase the apoptosis index of Reh cells in dose-and-time dependent manners. After treated with EGCG, the promoter region methylation status of the RUNX3 gene representing partial demethylation could be detected in Reh cells.RT-PCR and western blot also showed the mRNA level of RUNX3 was increased in dose-and-time dependent manner. CONCLUSION: EGCG could depress the proliferation rate of Reh. The possible mechanism might be its reversing the hypermethylation of RUNX3 gene and activiting the expression of RUNX3 gene.

Key words: Epigallocatechin-3-gallate, RUNX3, Methylation

CLC Number:

R965.2

WU Ming-cai, WEI Zhong-ling, JIANG Ming, FANG Ji-yong, BI Fu-yong. Effects of Epigallocatechin-3-galate on growth inhibition of Reh cell line and methylation of RUNX3 gene[J]. Chinese Journal of Clinical Pharmacology and Therapeutics, 2012, 17(6): 609-615.

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