Differential expression of microRNAs in patients with gastric cancer: a potential marker for gastric cancer recurrence screening

Objective To screen and establish specific miRNAs diagnostic fingerprint of gastric cancer recurrence. Methods Fifty gastric cancer patients with postoperative local recurrence and 50 gastric cancer patients with postoperative recurrence were selected after radical gastrectomy. The tumor tissues, paired para-cancerous normal tissues and preoperative serum specimens from these gastric cancer patients were collected. At the same time, serum from 50 cases with sex- and age-matched healthy controls was collected. Real-time quantitative polymerase chain reaction (Real-time PCR) technique was adopted to detect the expression of specific miRNAs and the relationship between specific miRNA and clinical pathological features of patients was analyzed. The expression of specific miRNAs was detected by Real-time PCR, and its relationship with clinicopathological characteristics of patients was analyzed. Results Five specific miRNAs of gastric cancer recurrence were screened, including miR-10b, miR-21, miR-183, miR-371-5p and miR-378. The expression of five kinds of miRNAs in serum was significantly correlated with the expression in tumor tissues (r=0.995, 0.988, 0.966, 0.985, 0.981; all P=0.000). The expression levels of five kinds of miRNAs in tumor tissues were significantly correlated with the depth of tumor invasion, lymph node staging, distant metastasis and clinical stage, respectively (all P=0.000). The postoperative recurrence time in patients with five highly expressed miRNAs was significantly shorter than in those with five normally or low expressed miRNAs (Log-rank=104.216, 100.260, 50.842, 98.185 and 92.136 respectively; all P=0.000). Conclusion The specific miRNAs fingerprint can predict the recurrence of patients with gastric cancer after radical gastrectomy. Key words: Gastric cancer; MicroRNAs; Recurrence; Prognosis