胃癌中硒结合蛋白-1的表达及其临床病理学意义

Expression and clinical significance of selenium binding protein 1 in gastric cancer

目的 检测硒结合蛋白1（SBP1）在胃癌细胞系SGC7901、BGC823、正常胃黏膜上皮细胞系GES-1、胃癌组织以及正常胃黏膜组织中的表达水平,分析其表达变化与胃癌临床病理因素之间的联系,探讨其作为胃癌标记物的可能性.方法 回顾性分析2006年至2007年武汉大学中南医院收治的135例胃癌患者的临床资料,利用免疫组织化学染色法对胃癌组织及16例正常胃黏膜组织中SBP1蛋白表达部位及水平进行测定,并进行半定量评分.Western blot和RT-PCR检测细胞系SGC7901、BGC823、GES-1中SBP1蛋白和mRNA的表达水平.组间比较采用单因素方差分析,SBP1表达强度与临床病理因素的关系采用x2检验.结果 SBP1 mRNA在胃癌细胞系BGC823、SGC7901中的表达分别为0.120±0.020、0.133±0.015,显著低于其在正常胃黏膜上皮细胞系GES-1中的表达（0.907±0.015）（F=2106.462,P＜0.05）.胃癌细胞系BGC823、SGC7901中的SBP1蛋白表达分别为0.253±0.015、0.273±0.015,显著低于其在正常胃黏膜上皮细胞系GES-1中的表达水平（0.877±0.025）（F=1026.758,P＜0.05）.3例胃癌组织中SBP1呈强免疫反应,而16例正常胃黏膜中SBP1呈强免疫反应.SBP1蛋白表达减少与胃癌患者临床分期相关（x2=12.629,P＜0.05）,而与患者的性别、年龄、肿瘤组织学分型、分化程度、浸润深度以及淋巴结转移无关（x2=2.142,0.860,1.838,5.001,4.858,1.994,P＞0.05）.结论 SBP1表达减少可以作为一种胃癌诊断的新指标.SBP1下调在胃癌发生及进展中可能发挥着重要作用.

Objective To detect the expression of selenium binding protein 1 （ SBP1 ） in gastric cancer cell line SGC7901, BGC823, normal gastric epithelial cell line GES-1, gastric cancer tissues and normal gastric tissues, explore the relationship between SBP1 and pathologic features, and discuss the feasibility of SBP1 as an diagnostic marker of gastric cancer. Methods The clinical data of 135 patients with gastric cancer who were admitted to Zhongnan Hospital of Wuhan University from 2006 to 2007 were retrospectively analyzed. The expression of SBP1 in the gastric cancer tissues and 16 cases of normal gastric tissues were detected by immunohistochemistry. The mRNA and protein expressions of SBP1 of SGC7901, BGC823 and GES-1 were determined by Western blot and RT-PCR. All data were analyzed by using chi-square test and one-way analysis of variance.Results The mRNA expressions of SBP1 in BGC823 and SGC7091 were 0. 120 ± 0. 020 and 0. 133 ± 0. 015,respectively, which were significantly lower than 0. 907 ± 0. 015 in GES-1 （ F = 2106. 462, P 〈 0.05 ）. The protein expression of SBP1 in BGC823 and SGC7901 were 0.253 ±0.015 and 0.273 ±0.015 ,respectively, which were significantly lower than 0.877 ±0.025 in GES-1 （ F = 1026. 758, P 〈0.05 ）. A strong positive reaction of SBP1 was observed in 3 cases of gastric cancer tissues and 16 cases of normal gastric tissues. The decrease of the protein expression of SBP1 was correlated with clinical stages of the patients （ x2 = 12. 629, P 〈 0.05 ）, rather than the sexes, ages, tumor histological types, tumor differentiation, infiltration depths and lymph node metastasis （x2 =2. 142, 0.860, 1.838, 5.001,4.858, 1.994, P〉0. 05）. Conclusions The decrease of SBP1 expression could be used as a marker in diagnosing gastric cancer. Down-regulation of SBP1 expression may play an important role in the genesis and prognosis of gastric cancer.