miRNA27a is a biomarker for predicting chemosensitivity and prognosis in metastatic or recurrent gastric cancer.

We previously identified five miRNAs (miR-1, miR-20a, miR-27a, miR-34a, and miR-423-5p) that are up-regulated in gastric cancer. The goal of this study was to investigate the value of these miRNAs as potential biomarkers for predicting chemosensitivity and prognosis in metastatic or recurrent gastric cancer patients who received first-line chemotherapy. A total of 82 patients with metastatic or recurrent GC receiving first-line chemotherapy were included in our study. The expression levels of the five miRNAs were evaluated using hydrolysis probe-based stem-loop quantitative reverse transcription polymerase chain reaction (qRT-PCR) in individual samples before first-line chemotherapy. Patients receiving first-line chemotherapy with fluoropyrimidine combined with oxaliplatin or paclitaxel were chosen for the chemosensitivity analysis. The relationships between expression of the five-miRNAs and clinicopathological parameters, response to chemotherapy and prognosis were analyzed statistically. Patients with higher miRNA1 expression levels tended to have a higher rate of liver metastasis, and higher miRNA34a expression levels occurred more frequently in males (P = 0.022). The expression of the remaining three miRNAs showed no obvious relationship to any of the clinicopathological features. The partial response rates of the patients with high miRNA1 expression and low miRNA1 expression were 11.1% and 23.1%, respectively (P = 0.048). Similar results were observed for miRNA27a (the partial response rate was 7.7% vs. 25.9%, P = 0.018). Patients with up-regulated miRNA27a expression had a significantly worse overall survival (OS) than patients with lower miRNA27a expression (P = 0.024). In patients with MRGC, miRNA27a is a potential biomarker for predicting resistance to fluoropyrimidine-based chemotherapy and a novel prognostic marker for gastric cancer.