Abstract:

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.