Flow Cytometric Analysis of Bhrf1 Expression Prohibiting Apoptosis Induced by Radiation

Abstract

The Epstein-Barr virus gene BHRF1 has homology with proto-oncogene bcl-2, which can protect cells from apoptosis. In order to investigate the effect of BHRF1 expression on the anti-apoptotic ability of nasopharyngeal carcinoma (NPC) cells after irradiation, a high—BHRF1 expression vector was constructed and transfected into the NPC cell line CNE₂. Then, the alteration of proliferation and apoptosis in the cells was tested by flow cytometry after cobalt 60 irradiation. The results showed that BHRF1 expression could increase G₁ delay and decrease the cell percentage in S phase before irradiation, and reduce the apoptotic rate of CNE₂ cells and increase the cell percentage in S phase after irradiation. The results suggest that BHRF1 expression is able to alter the cell cycle and protect CNE₂ cells from apoptosis induced by radiation.

Keywords

apoptosis BHRF1 gene radiation

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