Plasma microRNAs serve as novel potential biomarkers for early detection of gastric cancer

Recent studies have shown that microRNAs can be stably detected in human plasma and have the potential as non-invasive biomarkers for the diagnosis of cancers. This study evaluates the potential application of plasma microRNAs for the early detection of gastric cancer (GC). We first measured the plasma expression levels of 15 selected microRNAs (miR-1, -106a, -106b, -17-5p, -20a, -21, -221, -27a, -34, -376c, -378, -423-5p, -451, -486, -744) in 30 GC patients and 30 age-and gender-matched healthy controls and then validated those microRNAs that differentiating GC and controls in another 60 GC patients and 60 matched controls using quantitative reverse transcription-polymerase chain reaction. The areas under the receiver operating characteristic (ROC) curves were used to test the sensitivity and specificity of GC diagnosis using these identified plasma microRNAs. Three plasma microRNAs, miR-106b, miR-20a, and miR-221, were significantly elevated in GC patients than in healthy controls (P < 0.05). Furthermore, the areas under the ROC curves using miR-106b, miR-20a, and miR-221 for GC diagnosis were 0.7733 (95 % CI, 0.7758-0.8409), 0.8593 (95 % CI, 0.8046-0.9139), and 0.7960 (95 % CI, 0.7256-0.8664), respectively. Furthermore, these three microRNAs had a statistically significant elevation in GC patients compared with healthy controls at each of the four stages. However, there were no significant differences in the plasma levels of the three microRNAs among the four TNM stages (P > 0.05). Plasma miR-106b, miR-20a, and miR-221 have the potential as novel, non-invasive biomarkers for the early detection of GC.