维生素K_2对MDS细胞株SKM-1增殖抑制和诱导凋亡作用的研究

Study on the Proliferated-inhibition and Apoptosis of Myelodysplastic Syndrome Cell Line SKM-1 Treated with Vitamin K_2

目的研究维生素K2(VK2)对骨髓增生异常综合征(MDS)细胞株SKM-1的增殖抑制和诱导凋亡作用并探讨其可能机制。方法 (1)应用四甲基偶氮唑蓝(MTT)比色法测定VK2对SKM-1细胞增殖的抑制作用;(2)通过Annexin-V/PI标记VK2作用后的SKM-1细胞,用流式细胞术分析其凋亡情况;(3)通过流式细胞术检测SKM-1细胞线粒体膜电位(ΔΨm)的变化;(4)应用RT-PCR检测凋亡抑制基因Survivin的表达,分析VK2诱导SKM-1细胞凋亡的机制。结果 (1)5、10、20、40μmol/L VK2分别作用于SKM-1细胞24、48、72 h后,细胞增殖抑制明显(均P<0.05),生长抑制率的增加呈剂量依赖性(P<0.05);(2)不同浓度VK2处理后48h,SKM-1细胞发生凋亡(均P<0.01),细胞凋亡率的增加呈剂量依赖性(P<0.05);(3)不同浓度VK2作用后24 h,SKM-1细胞线粒体膜电位降低明显(均P<0.01),且呈剂量依赖性(P<0.01);(4)不同浓度VK2处理后48 h,SKM-1细胞Survivin基因表达随着VK2浓度的增大而明显下调(均P<0.05)。结论 (1)VK2对SKM-1细胞增殖有抑制作用,呈剂量依赖性;(2)VK2可诱导SKM-1细胞早期凋亡,呈剂量依赖性;(3)在此凋亡过程中,SKM-1细胞线粒体膜电位降低、凋亡抑制基因Survivin表达下调;(4)Survivin基因的表达下调可能是VK2诱导SKM-1细胞凋亡的机制之一。

Objective To study the proliferated-inhibition and apoptosis of myelodysplastic syndrome cell line SKM-1 treated with Vitamin K2（VK2） and explore their possible mechanism.Methods（1） MTT assay was used to observe the proliferated inhibition of SKM-1 cells treated with VK2.（2） The flow cytometry was used to analyze Annexin-V＋/PI-apoptotic rate.（3） The flow cytometry was used to detect the mitochondrial transmembrane potential.（4） The expression of apoptosis-inhibited gene Survivin was detected by reverse transcription-polym erase chain reaction（RT-PCR）.Results（1） VK2（5~40 μmol/L） could obviously inhibit the proliferation of SKM-1 cells after 24,48,72 hours（P0.05）,and the rate of growth inhibition increased in dose dependence（P0.05）.（2） SKM-1 cells could be significantly induced apoptosis by VK2after 48 hours（P0.01）,and the apoptotic rate increased in dose dependence（P0.05）.（3） The mitochondrial transmembrane potential decreased obviously after 24hours in dose dependence（P0.01）.（4） The expression of Survivin was significantly down-regulated by VK2 after 48 hours（P0.05）.Conclusions（1） VK2 can inhibit the proliferation of SKM-1 cells in dose dependence.（2） VK2 can induce apoptosis of SKM-1 cells in dose dependence.（3） In the process of apoptosis,the mitochondrial transmembrane potential loses and the expression of survivin is down.（4） Low-expression of Survivin gene may be the mechanism of apoptosis induced by VK2.