两歧双歧杆菌胞外多糖对胃癌细胞及端粒酶逆转录酶的影响  

Effect of exopolysaccharide from Bifidobacterium bifidum on cell of gastric cancer and human telomerase reverse transcriptase

作　　者：陈旭[1] 江虹锐[1] 杨艳梅[2] 刘宁[1] 

机构地区：[1]东北农业大学食品学院,乳品科学教育部重点实验室,哈尔滨150030 [2]哈尔滨医科大学肿瘤研究所,哈尔滨150040

出　　处：《微生物学报》2009年第1期117-122,共6页Acta Microbiologica Sinica

基　　金：国家自然科学基金(30371055)~~

摘　　要：【目的】研究从双歧杆菌属两歧双歧杆菌(Bifidobacterium bifidum)提取的细胞表面成分胞外多糖(Exopolysaccharide,B.EPS)对人胃癌细胞BGC-823的生长抑制作用及对端粒酶限速因子hTERT活性的影响。【方法】将3种不同浓度B.EPS体外作用于胃癌细胞BGC-823,MTT法检测细胞生长抑制率并辅以形态学观察;异硫氰酸盐(FITC)联合PI染色,通过流式细胞术检测肿瘤细胞初期调亡情况;肿瘤细胞端粒酶限速因子hTERT mRNA经RT-PCR检测B.EPS对端粒酶活性抑制作用;通过荧光分光光度计显示B.EPS对胃癌细胞作用后胞内Ca2+含量变化。【结果】经过检测发现,B.EPS对人胃癌细胞BGC823的生长显著抑制(P<0.05)呈剂量时间反应关系;细胞中hTERT mRNA在B.EPS的作用下表达降低(P<0.05),有一定剂量效应关系;随着B.EPS对肿瘤细胞的抑制,细胞内Ca2+含量显著增加(P<0.05)。【结论】B.EPS诱导人胃癌细胞BGC-823调亡的机制可能与改变肿瘤细胞端粒酶限速因子hTERT mRNA表达量和细胞内钙离子浓度有关。[ Objective ] To study the inhibition of human gastric cancer cell line BGC-823 by exopolysaecharide （ B. EPS） extracted from Bifidobacterium bifidum and the effect on the activity of telomerase rate-limiting factor human telomerase reverse transcriptase （hTERT） . [ Methods] In vitro human gastric cancer cell line BGC-823 were treated by three concentrations of B. EPS. The inhibition rate of gastric cancer cell line BGC-823, the morphology changes of cells and the apoptosis in the initial stage of cell was observed respectively by MTT, inverted fluorescent microscope and the Annexin V-FITC/PI flow cytometry. In addition, the effect of B. EPS on cell telomerase rate-limiting factor hTERT mRNA was tested by RT-PCR; the changes in the concentration of calcium ions inside the cytoplasm were detected by spectrofluorometer. [ Results] B. EPS inhibited the growth of gastric cancer cell BGC-823 （P 〈 0.05）, the inhibition rate increased and the concentration of B. EPS showed dose-time response relation. The expression of cell telomerase rate-limiting factor hTERT mRNA decrease after effected by B. EPS （ P 〈 0.05）, and showed dose-effect relation with B. EPS. The concentration of calcium ion in cytoplasm was higher than the control apparently （ P 〈 0.05）. [ Conclusion] The apoptosis mechanism of human gastric cancer cell line BGC-823 induced by B. EPS might be relevant with the changes of the hTERT mRNA expression and the calcium ions concentration in cytoplasm.

关 键 词：两歧双歧杆菌 胞外多糖 胃癌 细胞凋亡 HTERT 

分 类 号：R735.2[医药卫生—肿瘤]