Clinical significance of serum miR-25 as a diagnostic and prognostic biomarker in human gastric cancer.

Background and objective: MicroRNAs (miRNAs) are under investigation as novel diagnostic and prognostic biomarkers in several malignancies, including gastric cancer (GC). miR-25 was overexpressed in GC tissues, and higher miR-25 expression was statistically correlated with aggressive clinicopathological characteristics. In our study, we investigate the associations of serum miR-25 level with the clinicopathological characteristics, diagnosis and prognosis of GC patients.

Methods: Serum samples from 184 GC patients, 56 gastritis patients and 78 healthy controls were subjected to real-time quantitative polymerase chain reaction (RT-qPCR), and the relationship between micR-25 level and cliniopathological characteristics including diagnosis and prognosis was explored.

Results: Compared with the gastritis and healthy patients, serum miR-25 level was significantly up-regulated in patients with GC. Using a cut-off of 0.042, the level of miR-25 was significantly increased in serum samples from cancer patients; Using this test cancer patients were identified with 67.3-69.4% sensitivity and 80.4%-81.0% specificity. High serum miR-25 level was significantly associated with depth of invasion, lymph node metastasis and stage of disease. In univariate and multivariate analyses, miR-25 was an independent prognostic factor for overall survival (OS). Moreover, high serum miR-25 level was correlated with poor prognosis in patients subgroups stratified by tumor size, depth of invasion and lymph node metastasis. Serum miR-25 level was increased in both prominent serosal invasion group and lymph node metastasis group. Furthermore, stratified analysis showed that the TNM stage I-VI patients with high serum miR-25 level had poor prognosis than those with low serum miR-25 level.

Conclusions: Serum levels of miR-25 could improve gastric cancer screening, and as the better diagnostic and prognostic marker of gastric cancer.