同位素标记相对与绝对定量技术筛选出Vinculin蛋白在进展期胃癌组织中低表达及其预后意义

 目的 应用同位素标记相对与绝对定量蛋白组学（isobaric tags for relative and absolute quantification，iTRAQ）技术鉴定和筛选进展期胃癌复发转移相关的差异蛋白；检测筛选出的目标蛋白Vinculin表达水平及其预后意义。方法 应用iTRAQ技术在正常胃黏膜组织组、胃癌复发组和胃癌未复发组，检测差异表达的蛋白。然后选取差异性表达显著的Vinculin蛋白，采用免疫组织化学（immunohistochemistry，IHC）技术在110例人胃癌组织标本中检测其表达情况，并统计分析Vinculin蛋白表达量与临床病理学指标的关系；采用Kaplan-Meier生存曲线分析，探究Vinculin蛋白表达与胃癌患者生存期的关系。结果 Vinculin蛋白主要表达于细胞质中近胞膜处；在110例人胃癌组织标本中，Vinculin蛋白阳性表达46例（41.8%），缺失表达64例（58.2%）。统计结果显示，Vinculin蛋白缺失表达与淋巴结转移（P=0.018）、肿瘤TNM分期（P=0.022）、血管侵袭（P=0.002）显著正相关。Kaplan-Meier生存曲线分析结果显示，Vinculin缺失表达与胃癌患者不良预后正相关（P=0.011）。结论 Vinculin蛋白缺失表达与肿瘤转移和预后不良相关，提示其表达可以作为预测胃癌侵袭转移的潜在指标。

The expression of Vinculin screened by isobaric tags for relative and absolute quantification in advanced gastric cancer is decreaesd and its prognostic significance

Objective To identify and screen differential proteins related to recurrence and metastasis of advanced gastric cancer by isobaric tags for relative and absolute quantification (iTRAQ) and to evaluate the expression of Vinculin in gastric cancer and its prognostic significance. MethodsThe differentially expressed protein Vinculin was detected by iTRAQ in normal gastric mucosa,recurrent gastric cancer and non-recurrent gastric cancer.Then,the differentially expressed Vinculin protein was detected in 110 human gastric cancer tissue samples using immunohistochemistry (IHC) technology,and the relationship between Vinculin protein expression and clinicopathological indicators was statistically analyzed.Kaplan-Meier survival curve analysis was used to explore the relationship between Vinculin protein expression and survival time of gastric cancer patients.Results Vinculin protein mainly existed in the cytoplasm near the cell membrane.Among 110 human gastric cancer tissue specimens,Vinculin showed positive staining in 46 cases (41.8%) and negative staining in 64 cases (58.2%).Statistics showed that the expression deficiency of Vinculin had a significant positive correlation with lymph node metastasis (P=0.018),tumor TNM staging (P=0.022),and vascular invasion (P=0.002).Kaplan-Meier survival curve analysis showed that the expression deficiency of Vinculin was correlated with the poor prognosis of patients with gastric cancer (P=0.011).Conclusion The expression deficiency of Vinculin is significantly correlated with tumor metastasis and poor prognosis,suggesting that its expression can be used as a potential clinical indicator for predicting the invasion and metastasis of gastric cancer.