高压氧和三氧化二砷对K562细胞增殖抑制及相关机制研究

Effects of Hyperbaric Oxygenation Combined with As_2O_3 on Proliferation of K562 Cells and Associated Mechanism

本研究旨在探讨高压氧联合三氧化二砷(As2O3)对K562细胞增殖、凋亡及低氧诱导因子-1a(HIF-1a)、血管内皮生长因子(VEGF)及caspase-3 mRNA表达的影响。用MTT法检测各组K562细胞在药物作用各时间点(24、48、72 h)的增殖率;AnnexinⅤ/PI荧光标记法检测K562细胞的凋亡率;实时荧光定量PCR检测K562细胞HIF-1a、VEGF、caspase-3 mRNA的表达。结果表明:与单用As2O3比较,As2O3联合高压氧可使K562细胞的增殖抑制率增加,凋亡作用明显加强,并可明显下调HIF-1a、VEGF的表达,上调caspase-3的表达,两者联用具有协同作用,效果明显优于单用As2O3(P<0.05)。结论:高压氧联合As2O3对K562细胞抑制增殖及加速凋亡的作用优于单独应用As2O3;二者联合后HIF-1a、VEGF mRNA的表达减弱,而Caspase-3 mRNA的表达增强。HIF-1a、VEGF、caspase-3mRNA表达的变化可能是As2O3与高压氧联合产生抗白血病细胞协同作用的分子机制之一。

This study was aimed to explore the effects of hyperbaric oxygenation （HBO） alone or combined with As2O3 on proliferation, apoptosis and expression of HIF-1a, VEGF, caspase-3 mRNA of K562 ceils, and the molecular mechanism of As2O3 enhancing the anti-leukemic effect of HBO so as to provide a scientific basis for clinical treatment of chronic myeloid leukemia. The effects of drugs on proliferation of K562 cells was assayed by MTT method, the apop- tosis rate of K562 cells was detected by flow cytometry with Annexin V/PI doubie staining, the expressions of HIF-1a, VEGF, caspase-3 mRNA of K562 cells were determined by real-time quantitative PCR. The results showed that as com- pared with As2O3 alone, HBO combined with As2O3 could increase inhibitory rate of K562 cell proliferation, and en- hance apoptotic effect, obviously down-regulate expressions of HIF-1a and VEGF mRNA, up-regulate expression of caspase-3 mRNA. The effect of HBO combined with As2O3 was higher then effect of As2O3 alone, and their effects were synergistic （ P 〈 0.05 ）. It is concluded that HBO combined with As2 O3 can increase the expression of caspase 3 mRNA and decrease the expression of HIF-1a and VEGF mRNA, which may be one of molecular mechanisms underly- ing their synergisticc antileukemia efficacy.