Chuanjie Yang1, Yanling Wang2, Chun Hao1, Zengqiang Yuan3, Xiaodan Liu4, Fen Yang1, Huiqing Jiang1, Xiaoyu Jiang1, Pingkun Zhou4, Kuke Ding5. 1. Department of Gastroenterology, The Second Hospital of Hebei Medical UniversityShijiazhuang 050000, China; Hebei Key Laboratory of Gastroenterology, Hebei Institute of GastroenterologyShijiazhuang 050000, China. 2. Department of Gastroenterology, The Second Hospital of Hebei Medical UniversityShijiazhuang 050000, China; Hebei Key Laboratory of Gastroenterology, Hebei Institute of GastroenterologyShijiazhuang 050000, China; Cirrhosis Diagnosis and Treatment Center, 302 Military Hospital of ChinaBeijing 100039, China. 3. Institute of Biophysics, The Chinese Academy of Sciences Beijing 100101, China. 4. Department of Radiation Toxicology and Oncology, Beijing Institute of Radiation Medicine Beijing 100850, China. 5. National Institute for Radiological Protection, Chinese Center for Disease Control and PreventionBeijing 100088, China; Key Laboratory of Radiological Protection and Nuclear Emergency, Chinese Center for Disease Control and PreventionBeijing 100088, China.
Abstract
PURPOSE: To elucidate the mechanisms of the immediate-early response gene 5 (IER5) effect on the apoptosis induced by irradiation and cisplatin (CDDP) in human hepatocellular carcinoma (HepG2) cells. METHODS: We generated IER5 overexpression stable cells (HepG2/IER5) using Lipofectamine 2000 transfection HepG2 cells. Cell apoptosis was induced by irradiation and cisplatin treatments, and cell proliferation (viability) and apoptosis were evaluated by MTT and flow cytometry assays. Protein expression was determined by Western blot. RESULTS: The growth of the IER5 overexpression cells was significantly inhibited after six days of (60)Co γ-irradiation exposure (p<0.01) compared with the cell growth of vector control cells. Furthermore, the HepG2/IER5 cells were arrested at the G2/M phases. We also found that the expression of phospho-Akt was reduced, and the levels of cleaved caspase-3 and PARP were increased after the treatment of HepG2/IER5 cells with γ-irradiation and cisplatin. CONCLUSION: Our results suggest that the overexpression of IER5 can inhibit cell growth and enhance the cell apoptosis induced by exposure to radiation or cisplatin. The overexpression of IER5 can be utilized as a targeting strategy to improve the outcomes of radiotherapy used for the treatment of patients with liver cancer.
PURPOSE: To elucidate the mechanisms of the immediate-early response gene 5 (IER5) effect on the apoptosis induced by irradiation and cisplatin (CDDP) in humanhepatocellular carcinoma (HepG2) cells. METHODS: We generated IER5 overexpression stable cells (HepG2/IER5) using Lipofectamine 2000 transfection HepG2 cells. Cell apoptosis was induced by irradiation and cisplatin treatments, and cell proliferation (viability) and apoptosis were evaluated by MTT and flow cytometry assays. Protein expression was determined by Western blot. RESULTS: The growth of the IER5 overexpression cells was significantly inhibited after six days of (60)Co γ-irradiation exposure (p<0.01) compared with the cell growth of vector control cells. Furthermore, the HepG2/IER5 cells were arrested at the G2/M phases. We also found that the expression of phospho-Akt was reduced, and the levels of cleaved caspase-3 and PARP were increased after the treatment of HepG2/IER5 cells with γ-irradiation and cisplatin. CONCLUSION: Our results suggest that the overexpression of IER5 can inhibit cell growth and enhance the cell apoptosis induced by exposure to radiation or cisplatin. The overexpression of IER5 can be utilized as a targeting strategy to improve the outcomes of radiotherapy used for the treatment of patients with liver cancer.
Entities:
Keywords:
IER5; apoptosis; cisplatin; human hepatocellular carcinoma; γ-irradiation