B-RAF基因特异的siRNA干扰对胃癌BGC823细胞的影响

为探讨B-RAF基因特异的siRNA干扰对胃癌BGC823细胞的增殖和凋亡的影响, 设计并合成B-RAF小分子干扰RNA(B-RAF-siRNA)和阴性对照siRNA, 用TransMessenger介导转染胃癌BGC823细胞, RT-PCR分析检测胃癌BGC823细胞中B-RAF基因以及Bcl-2基因的表达; MTT检测胃癌BGC823细胞增殖情况; 流式细胞仪检测细胞凋亡情况, 并与对照组进行比较。TransMessenger能够有效介导B-RAF-siRNA和阴性对照siRNA转染胃癌BGC823细胞, TransMessenger介导的B-RAF-siRNA有效地抑制胃癌BGC823细胞B-RAF以及Bcl-2基因的表达, 与对照组相比, 抑制率达90.0%以上, 最高达100%; 同时明显抑制胃癌BGC823细胞增殖; 促进胃癌BGC823细胞的凋亡(P < 0.01)。B-RAF基因特异的siRNA干扰能有效地抑制胃癌BGC823细胞中B-RAF基因以及Bcl-2基因的表达, 同时促进胃癌细胞凋亡和抑制胃癌细胞增殖。     

胃癌中APC基因I1307K突变及蛋白质表达

为探讨肿瘤抑制基因APC结构及表达异常与胃癌发生、发展的关系,采用ARMS PCR检测胃癌中APC基因I1307K突变存在与否,免疫组织化学方法分析胃癌中APC蛋白表达水平。结果表明,在 62例胃癌高发区易感人群血液标本及45例胃癌中未检测到I1307K突变;胃癌（早期、进展期）中APC蛋白表达阳性率显著低于正常黏膜,进展期胃癌中APC蛋白表达阳性率显著低于早期胃癌,淋巴结转移阳性的胃癌中APC蛋白表达阳性率显著低于淋巴结转移阴性者。因此认为I1307K突变可能与国人胃癌发生无明显相关;APC蛋白低表达与胃癌发生、进展及淋巴结转移密切相关。 Abstract:In order to explore the correlation of the abnormalities of tumor suppressor gene APC with the carcinogenesis and progression of gastric cancer.The I1307K mutation of APC gene in gastric cancer was analysed using Amplification Refractory Mutation System PCR(ARMS ,PCR),also the expression of APC protein in gastric cancer of different stages was detected by immunohistochemical method.We found that there wasn't I1307K mutation of APC gene in 62 cases of blood samples of susceptible population in high incidence areas of gastric cancer and 45 cases of gastric cancer tissues.The positive rates of APC protein in gastric cancer (both early and progressive gastric cancer) were significantly lower than that in normal mucosa,the positive rates of APC protein in progressive gastric cancer were significantly lower than that in early gastric cancer,the positive rates of APC protein in gastric cancer with lymph node metastasis were significantly lower than that in gastric cancer without lymph node metastasis.So it was thought that there might be no correlation between the I1307K mutation of APC gene and carcinogenesis of gastric cancer in China,but the decreased expression of APC protein was closely related to the carcinogenesis,progression and lymph node metastasisof gastric cancer.     

低氧模拟剂氯化钴对胃癌细胞BGC823中S100A4基因表达的影响

摘要: S100A4基因是肿瘤侵袭转移相关的重要基因, 该基因高表达与胃癌浸润、淋巴结转移及胃癌细胞体外侵袭力密切相关。为探讨S100A4基因高表达的机制, 文章应用低氧模拟剂氯化钴处理胃癌细胞BGC823, RT-PCR、免疫组化、免疫荧光及Western blotting方法分别检测BGC823细胞中S100A4 mRNA及蛋白表达情况。结果显示, 氯化钴处理胃癌BGC823细胞后, S100A4 mRNA及蛋白表达明显增加。提示低氧模拟剂氯化钴可促进胃癌细胞BGC823中S100A4 基因表达。