Bcl-xL可能介导组织蛋白酶D相关的K562细胞凋亡  

Role of Bcl-xL in the Cathepsin D-Associated Apoptosis of K562 cells

作　　者：朴瑛[1] 刘丽梅[2] 陈协群[1] 梁蓉[1] 黄高昇[3] 乔岩[4] 王爱勤[4] 王哲[3] 

机构地区：[1]第四军医大学西京医院血液内科,西安710032 [2]沈阳军区总医院血液内科,沈阳110016 [3]第四军医大学病理学教研室,西安710032 [4]中国科学院兰州化学物理研究所,兰州730000

出　　处：《中国实验血液学杂志》2005年第3期379-382,共4页Journal of Experimental Hematology

基　　金：国家自然科学基金资助项目(No.30000198)

摘　　要：组织蛋白酶(cathepsin)D在氨基葡萄糖硫酸盐(glucosaminesulfate,GS)诱导的慢性髓系白血病K562细胞凋亡过程中为激活线粒体途径的可能的中介分子。为了探讨BclxL在氨基葡萄糖硫酸盐诱导慢性髓系白血病K562细胞凋亡中的可能作用,在倒置显微镜下动态观察细胞生长变化,采用瑞氏-姬姆萨染色观察细胞加药前后的形态学改变,间接免疫荧光法观察GS诱导K562细胞凋亡过程中cathepsinD和细胞色素(cytochrome)C的转位情况,Westernblot检测K562细胞凋亡过程中BclxL、Bax、Bid蛋白的表达变化。结果表明:5mmol/L氨基葡萄糖硫酸盐作用于K562细胞72小时后,细胞增殖受到明显抑制,胞浆出现空泡化;荧光显微镜显示cathepsinD和cytochromeC的荧光信号由颗粒状趋向弥散;BclxL蛋白在GS加药组中表达减低,甚至消失,但在抑胃酶肽(pepstatin)A预处理后的加药组中表达没有明显改变,Bax和Bid蛋白表达在凋亡前后没有明显变化。结论:BclxL蛋白在GS诱导白血病K562细胞凋亡过程中可能介导cathepsinD与线粒体途径之间的联系。The purpose of study was to explore the possible functions of Bcl-xL in the glucosamine sulfate-induced apoptosis of chronic myeloid leukemia K562 cells. Light microscopy and Wright-Giemsa staining were used to investigate the morphologic evidences for apoptosis of K562 cells induced by glucosamine sulfate (GS); immunofluorescence was used to observe the translocation of cathepsin D and cytochrome C during the apoptosis; Western blot was performed to detect the expression of Bcl-xL,Bid,Bax in K562 cells treated by GS. The results showed that many vacuoles were observed in the cytoplasma of the K562 cells treated by GS; fluorescent signals of cathepsin D and cytochrome were fransformed from granules to disperse form by using immunofluorescene; the expression of Bcl-xL was found down-regulated in K562 cells treated by GS, but not in the cells pre-treated with pepstatin A; the significant changes were not detected in expression of Bax and Bid protein before or after apoptosis. It is concluded that Bcl-xL protein may mediate relationship between cathepsin D and mitochondia pathway, Cathepsin D may play an important role in the GS inducing apoptosis of K562 cells through downregulation of Bcl-xL expression.

关 键 词：氨基葡萄糖硫酸盐 K562细胞 细胞凋亡 CATHEPSIND BCL-2家族 BCL-XL 

分 类 号：R733.7[医药卫生—肿瘤]