胃癌组织中Livin、Smac的表达及两者的相关性研究

Study of the expression and correlation of Livin and Smac in gastric carcinoma

目的本研究检测Livin、Smac在胃癌组织中的表达,观察其表达水平与胃癌各临床病理因素的关系。方法应用实时荧光定量逆转录PCR SYBR Green荧光染料法检测42例胃癌组织及20例癌旁正常胃组织中Livin两种转录变体(Livinα和Livinβ)及Smac/DIABLO mRNA的表达,免疫组化SP法检测两种蛋白的表达。结果癌旁正常组织中Livinα和LivinβmRNA相对表达量分别为(1.11+0.13)和(0.97+0.14);胃癌组织中Livinα和LivinβmRNA的表达显著上调,相对表达量分别为(7.05+2.66)和(6.19+2.54),差别均有显著的统计学意义(P<0.01)。低分化胃癌组Livin的表达显著高于中高分化胃癌组(χ2=5.54,P<0.05),有淋巴结转移组Livin的表达显著高于无淋巴结转移组(χ2=5.09,P<0.05),TNMⅢ+Ⅳ组Livin的表达显著高于TNMⅠ+Ⅱ组(χ2=4.40,P<0.05),而与年龄、性别及肿瘤大小无关,Livin mRNA与蛋白的表达结果基本一致;胃癌组织中Smac mRNA的相对表达量(0.69+0.26)低于癌旁正常组织(0.98+0.15),且差异有显著的统计学意义(P<0.01)。Smac在TNMⅠ+Ⅱ组的表达显著高于TNMⅢ+Ⅳ组(χ2=6.18,P<0.05),其表达与年龄、性别、肿瘤大小、淋巴结转移及分化程度无关。Smac蛋白表达与mRNA表达基本一致。结论 Livin与Smac在不同阶段胃癌中的表达及相关性存在差异,Livin基因高表达与胃癌的发生及分化转移密切相关。

【Objective】The proapoptotic gene Smac interacts with inhibitor of apoptosis protein Livin,which may contribute to regulating the impetus and progression of canceration.This study was to investigate the expression of Livin and Smac and their correlations to the clinicopathological features in gastric carcinomas.【Methods】The expression levels of 2 Livin splicing variants（Livin α and Livin β） and Smac mRNA in 42 gastric carcinoma specimens,and 20 para-cancerous normal gastric tissues were detected by the SYBR green real-time fluorescent quantitative reverse transcription PCR.The protein expression of Livin and Smac were measured by immunohisto-chemistry（SP method）.【Results】The expression of Livin α and Livin β mRNA was significantly upregulated in gastric carcinomas（7.05 ＋ 2.66;6.19 ＋ 2.54） compared with para-cancerous normal gastric tissues（1.11 ＋ 0.13;0.97 ＋ 0.14）,（P0.01）.The expression of Livin was higher in poorly differentiated gastric carcinomas,carcinomas with lymph node metastases and TNM stageⅢ＋Ⅳ than in highly differentiated gastric carcinomas,carcinomas without lymph node metastases and TNM stage Ⅰ＋Ⅱ（χ2= 5.54,P 0.05;χ25.09,P 0.05;χ2=4.40,P 0.05）.The expression of Livin had no correlation to age,gender,and tumor site（P 0.05）.The protein expression of Livin was consistant with that of its mRNA expression.The expression level of Smac mRNA was lower in gastric carcinomas（0.69±0.26） than in para-cancerous normal gastric tissues（0.98±0.15）,and there was significant difference（P 0.01）.The expression of Smac was higher in TNM stage Ⅰ＋Ⅱthan TNM stage Ⅲ＋Ⅳ（χ2=5.40,P 0.05）.The expression of Smac had nocorrelation to age,gender,tumor site,lymph node metastases and differentiated gastric carcinomas.The protein expression of Smac was consistent with that of its mRNA expression.【Conclusion】The expression and correlation ofLivin and Smac vary in different stages of gastric carcinoma.Overexpression of Livin is closely related to differentiation and metastases of gastric carcinoma.