Effect of EZH2 Inhibition on Colorectal Cancer Cells: an In Vitro Study

Document Type: Research Article


1 Department of Biology, Damghan Branch, Islamic Azad University, Damghan, Iran

2 Department of Biology, Hakim Sabzevari University, Sabzevar, Iran

3 Department of Medicine, The University of Kansas Medical School

4 Cellular and Molecular Research Center, Sabzevar University of Medical Sciences, Sabzevar, Iran


Recently, the epigenetic modifications have been recognized as a regulator of gene expression in various cancers. EZH2 gene is one the most important component of the PRC2 complex. Overexpression of EZH2 was identified in multiple cancers that considered more attractive the EZH2 role as an oncogene. Some studies report that EZH2 contributes to various aspects of colorectal cancer (CRC). However accurate evaluation of the role of EZH2 in the CRC cancer requires more extensive study. In this study, we treated HCT116 cells with the transduction of EZH2-shRNA. Here we observed that the expression level of EZH2 was lower in the treatment cell groups compared to control cells groups. We also found that inhibiting ezh2 induced caspase-3 gene expression, while no significant change was observed in the expression of BAX gene. Caspase-3 and BAX play a central role in the cell apoptosis. In addition, we found that downregulation of the Ezh2 gene decreased cell proliferation in CRC cells. Collectively, our results suggest that the reduced expression of Ezh2 altered the caspase-3 gene expression that could indicate the increase of apoptosis in HCT116 cells, which we suggest to direct effect on decreased cell growth. Meanwhile, suggest that EZH2 can be a useful target for therapy and poor prognosis in cancer.


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