双歧杆菌完整肽聚糖对实验性胃癌增殖及凋亡的影响  

Effect of whole peptidoglycan of bifidobacterium on proliferation and apoptosis in experimental gastric cancer

作　　者：杨平[1,2] 刘宁[1,2] 张春燕[3] 杨悦[3] 

机构地区：[1]东北农业大学乳品科学教育部重点实验室 [2]食品学院,黑龙江哈尔滨150030 [3]哈尔滨医科大学肿瘤研究所,黑龙江哈尔滨150081

出　　处：《中华肿瘤防治杂志》2007年第19期1441-1444,共4页Chinese Journal of Cancer Prevention and Treatment

基　　金：国家自然科学基金(30371055)

摘　　要：目的:探讨双歧杆菌完整肽聚糖(whole peptidoglycan,WPG)对实验性胃癌增殖及凋亡的影响。方法:用胃癌MKN-45细胞裸鼠皮下移植瘤模型,观察不同浓度WPG与5-氟尿嘧啶(5-FU)移植瘤的生长情况,原位末端标记(TUNEL)法检测肿瘤细胞凋亡情况,免疫组化法检测bcl-2和bax及增殖细胞核抗原(PC-NA)的表达。结果:连续灌胃100、300及500μg的WPG后,移植瘤的生长速度明显减慢。实验结束时,各组瘤质量明显低于对照组,P<0.01。但与5-FU组相比差异无统计学意义,P>0.05。WPG各组及5-FU组的凋亡指数显著高于对照组,P<0.01。免疫组化结果显示,WPG各组移植瘤的bcl-2与PCNA表达率及与对照组相比均有所降低,P<0.05;bax的表达情况相反,WPG各组中的bax表达显著高于对照组,P<0.01。结论:WPG对人胃癌裸鼠移植瘤的生长具有明显的抑制作用,其机制可能与降低肿瘤细胞的增殖活性及增强bax的蛋白表达、下调bcl-2的蛋白表达、诱导肿瘤细胞凋亡有关。OBJECTIVE： To explore the effects of whole peptidoglycan（WPG） from bifidobacterium on proliferation and apoptosis in experimental gastric cancer in vivo. METHODS： Thirty nude mice subcutaneously transplanted with MKN-45 human gastric cancer cells were administered with different doses of WPG and 5-FU by intraperitoneal injection when the tumors were palpable. The weights of the tumors and inhibitory rates were observed. TUNEL staining was used to detect the apoptosis of transplanted tumor cells. The immunohistochemical staining was used to detect the expression of bcl-2, bax and proliferating cell nuclear antigen （PCNA） in the transplanted tumor. RESULTS： The growth rates of the tumors in vivo were obviously slower when intragastrie administration of WPG, and the tumor weights were significantly lower than those in the NS group when the study was over, P〈0.01. But not significantly different from 5-FU group, P〉0. 05. The apoptosis indexes in the three WPG groups and 5-FU group were significantly higher than that in the normal saline group, P 〈0.01. The immunohistochemical staining showed that the expression rate of bcl-2 protein and proliferating cell nuclear antigen were significantly lowed down in the WPG group compared with the normal saline group （P〈0.05）, while the expression of apoptosis-inducing protein and bax was just the opposite. It was greatly up-regulated by WPG, P〈0.01. CONCLUSIONS： The whole peptidoglycan of bifidobacterium exerts an inhibiting effect on the growth of human gastric cancer in nude mice. The possible antitumor mechanisms are to decrease the proliferating activity of tumor cells or the expression of bcl-2 gene and increase the expression of bax gene, which can induce the apoptosis of the tumor cells.

关 键 词：多糖类/药理学 胃肿瘤/药物疗法 细胞凋亡 小鼠 裸 

分 类 号：R735.2[医药卫生—肿瘤]