胃癌组织与血清miR-126的表达及临床意义

目的：分析胃癌患者癌组织与血清miR-126的表达水平，探讨胃癌组织与血清miR-126在胃癌诊断中的价值。方法：收集42对胃癌组织及其对应的远癌对照组织（距离癌组织5 cm以上）为实验组，60例年龄相近的健康人群作对照组，标本系胃癌根治术后新鲜标本，采集患者术前、术后1周及健康对照组人群的外周血各5 mL，采用实时定量PCR法检测miR-126在癌组织和患者血清中的表达情况，另采集患者术前、术后1周的外周血各5 mL送检验科做癌胚抗原（CEA）检测。根据组织及血清中miR-126检测结果和CEA值作ROC曲线判断诊断效率。结果：胃癌组织miR-126的相对表达水平低于远癌对照组织（t=7.276，P < 0.05）；miR-126在癌组织中的表达与肿瘤大小、临床分期、组织分化程度有关；在胃癌患者血清中，术前血清miR-126的相对表达水平低于术后（t=6.316，P < 0.05）；术后血清中的相对表达水平低于健康对照者（t=4.338，P < 0.05）；miR-126在血清中的表达与肿瘤临床分期、组织分化程度有关；胃癌组织miR-126的诊断效率ROC曲线下面积（AUC）为0.823，血清AUC为0.776，CEA的诊断效率AUC为0.537。Pearson相关分析显示，胃癌患者癌组织与术前血清中miR-126的相对表达水平呈正相关（r=0.484，P < 0.01）。结论：胃癌组织和血清中miR-126表达下调；血清miR-126可以作为评估胃癌患者病情严重程度的标志之一；血清miR-126的表达对胃癌具有较好的诊断价值，优于血清CEA；胃癌组织和血清miR-126的表达水平呈正相关，有望成为诊断早期胃癌和监测胃癌复发的生物学标志物。

Expression and clinical significance of miR-126 in tissues and serum of gastric cancer

OBJECTIVE:To analyze expression of miR-126 in the tissues and serum of gastric cancer as diagnostic biomarkers.METHODS:Subjects for the study group were 42 cases of gastric cancer patients. The control group were 60 healthy individuals of similar age and gender. Fresh surgical specimens were collected after radical gastrectomy. Blood samples were collected from controls and from the patients before and at one week after the operation. miR-126 expression in tissues and serum were analyzed using quantitative real-time PCR and CEA test in the lab. RESULTS:For gastric cancer tissues,miR-126 expression,which was related to tumor size,clinical stage and differentiation degree,was significantly lower in the cancer tissues than in the distal cancerous contrast tissues, t=7.276,P<0.05. miR-126 expression in the pre-operative serum,which was related to tumor clinical stage and differentiation degree,was significantly lower than that in the post-operative serum,t=6.316,P<0.05;and the miR-126 expression in the post-operative serum was significantly lower than that in the healthy control group,t=4.338, P<0.05. The AUC of the ROC Curve of diagnostic efficiency of miR-126 expression was 0.823 in gastric cancer tissues and 0.776 in serum. The AUC of CEA diagnostic efficiency was 0.537,P>0.05. Pearson correlation analysis showed positive correlation coefficient of miR-126 expression in tissues and pre-operative serum of gastric cancer at 0.484. CONCLUSION:miR-126 expression was down-regulated in gastric cancer tissues and serum. miR-126 expressions in the serum can possibly be used as an indicator for the severity of gastric cancer. miR-126 expressions in serum had desirable diagnostic values of gastric cancer,better than the serum CEA test. miR-126 expression levels in tissues and serum were positively related,therefore it may become valuable biomarkers for diagnosing early stage of gastric cancer and monitoring of recurrence.