摘要
为了探讨羟甲基戊二酸单酰辅酶A(HMG CoA)还原酶抑制剂对多发性骨髓瘤 (MM)细胞增殖与凋亡的调控作用及机制 ,应用MTT比色法、光镜形态学观察、流式细胞术、DNA凝胶电泳及RT PCR研究了美伐他汀(mevastatin )对MM细胞系U2 6 6细胞体外增殖与凋亡的影响。结果显示 ,美伐他汀以剂量及时间依赖方式抑制U2 6 6细胞增殖 ;细胞周期分析显示美伐他汀诱导U2 6 6细胞G0 -G1 期阻滞 ,但对 p2 7蛋白及mRNA的表达无影响 ;在美伐他汀作用下U2 6 6细胞出现核染色质凝聚、核固缩、核碎裂等凋亡形态改变 ,PI- AnnexinⅤ + 细胞增多 ,线粒体跨膜电位 (△ψm)下降 ,DNA凝胶电泳出现梯形条带 ,bcl 2mRNA表达下调。加入外源性甲羟戊酸 (meva lonate,MVA)可完全逆转美伐他汀对U2 6 6细胞增殖与凋亡的效应。结论 :美伐他汀可通过MVA途径 ,诱导G0-G1 期阻滞抑制增殖、下调bcl 2表达及降低线粒体膜电位触发U2 6 6细胞凋亡。
In order to investigate the anti-tumor activity of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors and the mechanism underlying the cell proliferation and apoptosis modulated in myeloma cells,the effects of mevastatin,an HMG-CoA reductase inhibitor,on cell growth,cell cycle progression and apoptosis in U266 human multiple myeloma (MM) cell line in vitro were explored by MTT colorimetric assay,morphologic observation,flow cytometry,DNA gel electrophoresis,and RT-PCR. The results demonstrated that mevastatin inhibited the growth of U266 cells in time- and dose-dependent manners. Cell cycle analysis showed that U266 cells underwent G 0/G 1 arrest under exposure to mevastatin,but it did not affect p27 expression at both mRNA and protein level. Morphologic observations revealed cytoplasm shrinkage,nuclear condensation and fragmentation in mevastatin-treated cells,and fraction of annexinⅤ+PI- cells increased significantly in the presence of the agent as determined by flow cytometric assay. In addition,mevastatin caused the collapse of mitochondrial transmembrane potential (Δψm),induced DNA fragmentation,and down-regulated the mRNA expression of bcl-2. The growth-inhibitory,cell cycle arresting,and proapoptotic effects of mevastatin in U266 cells could be effectively reversed by the addition of mevalonate (MVA),the immediate endproduct of the reaction catalyzed by HMG-CoA reductase. It is concluded that mevastatin suppresses proliferation by inducing G 0/G 1 phase arrest and triggering apoptosis via down-regulation of bcl-2 and reduction of Δψm,which may be attributed to the inhibition of MVA pathway by mevastatin. Statins including mevastatin may find their future application in the treatment of MM.
出处
《中国实验血液学杂志》
CAS
CSCD
2004年第3期340-345,共6页
Journal of Experimental Hematology
