高压氧和三氧化二砷对K562细胞增殖抑制及相关机制研究

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。

Effects of hyperbaric oxygenation combined with As(2)O(3) on proliferation of K562 cells and associated mechanism

This study was aimed to explore the effects of hyperbaric oxygenation (HBO) alone or combined with As(2)O(3) on proliferation, apoptosis and expression of HIF-1a, VEGF, caspase-3 mRNA of K562 cells, and the molecular mechanism of As(2)O(3) 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 apoptosis rate of K562 cells was detected by flow cytometry with Annexin V/PI double 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 compared with As(2)O(3) alone, HBO combined with As(2)O(3) could increase inhibitory rate of K562 cell proliferation, and enhance 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 As(2)O(3) was higher then effect of As(2)O(3) alone, and their effects were synergistic (P < 0.05). It is concluded that HBO combined with As(2)O(3) 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 underlying their synergistic antileukemia efficacy.