G6PD缺陷抑制人黑色素瘤细胞裸鼠移植瘤的生长  

G6PD Defect Inhibits the Growth of Nude Mice Xenograft Tumor in Human Melanoma Cells

作　　者：胡滔[1,2] 陈龙[1] 张春华[1,3] 唐琼玲[1,4] 李波[1] 张正[1] 蔡天池 朱月春[1] 

机构地区：[1]昆明医科大学生物化学与分子生物学系,昆明650500 [2]云南省第三人民医院,昆明650011 [3]云南省妇幼保健院,昆明650051 [4]深圳市罗湖区妇幼保健院,深圳518020

出　　处：《中国生物化学与分子生物学报》2012年第11期1018-1025,共8页Chinese Journal of Biochemistry and Molecular Biology

基　　金：国家自然科学基金(No.81160246;30860322);云南省后备人才培养基金(No.2007PY01-13)~~

摘　　要：敲减葡糖6-磷酸脱氢酶(G6PD)表达的人黑色素瘤A375细胞(A375-G6PDΔ)呈现生长增殖抑制和凋亡率升高.为明确G6PD缺陷对裸鼠体内成瘤的影响及其可能机制,用A375-WT与A375-G6PDΔ细胞制作裸鼠荷瘤模型,观察体内瘤体生长,real-time PCR、免疫组织化学染色与紫外分光光度法分别检测瘤体组织G6PD mRNA、G6PD蛋白及酶活性,Western印迹分析凋亡相关蛋白,分光光度法测定NADPH和GSH/GSSG水平.结果显示,A375-G6PDΔ细胞注射组的裸鼠成瘤时间延长,瘤体生长明显减慢,瘤体的体积与质量显著低于A375-WT细胞注射组(P<0.01);与A375-WT细胞注射组相比,A375-G6PDΔ细胞注射组的裸鼠瘤体组织中G6PD mRNA表达、G6PD阳性细胞数与G6PD活性分别降低了87.10%、77.20%与75.77%(P<0.01),G6PD、p53和Bcl-2的表达分别降低了67.92%、65.54%和62.32%(P<0.01),Fas升高了86.38%(P<0.01),NADPH和GSH/GSSG分别降低了74.37%和86.02%(P<0.01).结果提示,G6PD缺陷可能通过减少核酸等合成的原料、改变细胞内氧化还原状态及凋亡相关蛋白表达抑制裸鼠瘤体生长与增殖,这为黑色素瘤发生和治疗研究提供了新的线索.Human melanoma A375 cells with glucose-6-phosphate dehydrogenase（G6PD） knock-down（A375-G6PDΔ） were characterized by a reduced proliferation and an increase of apoptotic rate.To elucidate the effect and mechanism of G6PD deficiency on xenograft tumor in vivo,the nude mice xenograft model of human melanoma was established using A375-WT and A375-G6PDΔ cells and the growth of xenograft was observed.G6PD mRNA,G6PD protein and activities in the xenograft tumor tissue were checked by real-time PCR,immunohistochemistry staining and ultraviolet spectrophotometry method,respectively,accompanied by detecting expression of apoptosis-related proteins with Western blotting and levels of NADPH and GSH/GSSG with spectrophotometry method.In comparison with the injection of A375-WT cells,the nude mice bearing-melanoma of A375-G6PDΔ-treated group displayed an extended tumorigenic time and a slower growth,in keeping with the significantly less volume and weight of tumor（P0.01）.Further study showed that the expressions of G6PD mRNA and G6PD protein in the xenograft tumor tissues of A375-G6PDΔ cells decreased by 87.10% and 67.92%%（both P0.01）,respectively,with a 75.77% reduction of G6PD activity（P0.01）.Simultaneously,p53 and Bcl-2 expression decreased by 65.54% and 62.32%（both P0.01）,respectively,with an 86.38% increase of Fas（P0.01）,a 74.37% descent of NADPH（P0.01） and an 86.02% drop of GSH/GSSG ratio（P0.01）,as those of A375-WT-treated group.The results indicate that G6PD inhibits the growth of the nude mice xenograft of human melanoma through a reduction of materials in nucleic acid synthesis,a change of redox status and a regulation of apoptosis-related proteins expression,which may be a new clue in the study of melanoma tumorigenesis and therapy.

关 键 词：葡糖6-磷酸脱氢酶 黑色素瘤 裸鼠 凋亡蛋白 氧化还原 

分 类 号：R730.22[医药卫生—肿瘤] Q554[医药卫生—临床医学]