三氧化二砷联合抗坏血酸对肝癌细胞增殖和凋亡的影响

Combination of arsenic trioxide and ascorbic acid inhibits proliferation and induces apoptosis in human hepatoma cell line

目的:研究三氧化二砷(As2O3)联合抗坏血酸(AA)对肝癌HepG2细胞增殖和凋亡的影响,并探讨其细胞内谷胱甘肽(GSH)水平.方法:As2O3和AA不同组合孵育细胞HepG2,采用台盼蓝染色实验检测药物对细胞生长的影响,流式细胞仪检测亚二倍体凋亡峰,AnnexinV染色检测细胞凋亡率,GSH实验检测细胞内GSH水平.结果:100μmol/L的AA单独作用与对照组相比在细胞增殖和凋亡都无显著性差异;低剂量(2μmol/L)和高剂量(5μmol/L)的As2O3都能抑制细胞增殖活性和诱导细胞凋亡,联合AA作用后,比相应浓度的单独As2O3作用更为显著;AA和As2O3分别处理都能明显消减细胞GSH含量,两种药物联合作用后与相应单独As2O3作用相比GSH水平显著性降低.结论:GSH在As2O3对肝癌细胞抑制增殖和诱导凋亡作用机制中起到重要的作用,高低剂量的As2O3联合AA通过降低GSH水平均可以增强As2O3对肝癌细胞抑制生长及其诱导凋亡作用的敏感性.

AIM: To study the synergistic effect of ascorbic acid (AA) and arsenic trioxide (As 2O 3) on the inhibition of proliferation and the induction of apoptosis in hepatoma cell line and to explore the effect of cellular glutathione (GSH) level on As 2O 3. METHODS: HepG2 cells were treated with As 2O 3 alone or in combination with AA. The viability of cells was determined by Trypan-blue assay and sub-G1 cells were detected by flow cytometry (FCM). The apoptosis rate was assessed by AnnexinV-PI staining and the GSH content was detected by GSH assay. RESULTS: 100 μmol/L AA had no influence on the proliferation and apoptosis in HepG2 cells. With As 2O 3 at the dosage of 2 μmol/L and 5 μmol/L, the combination of As 2O 3 and AA effectively enhanced the growth inhibition, compared to separate use of either alone. The cells treated by the two agents potentiated the apoptosis rate, compared with that of As 2O 3 alone. When cells were treated with AA or As 2O 3, the intracellular GSH content decreased markedly. The intracellular GSH content decreased significantly in cells treated with two agents, compared with that of As 2O 3 alone. CONCLUSION: The intracellular GSH content plays an important role in As 2O 3. Combined use of AA and As 2O 3 can made HepG2 cells more sensitive to As 2O 3 by decreasing the GSH level.