Gastric cancer (GC) is the second most common
cancer in China and the second leading cause of
cancer-related death in the world. Identifying circulating
biomarkers is helpful to improve
theranostics of
gastric cancer. Herein, we are for the first time to report miR-16-5p and miR-19b-3p were identified to be the novel potential plasma
biomarkers to detect
gastric cancer. Differentially expressed
miRNAs were initially screened out by genome-wide
miRNA profiling microarrays between 16 plasma samples of
gastric cancer and 18 matched normal controls, and then were quantified and validated by quantitative reverse transcription-PCR method between 155
gastric cancer cases and 111 normal controls. Additionally, 30 plasma samples from precancerous lesions and 18 paired samples from
gastric cancer patients with
gastrectomy were further detected. Results showed that based on two normalization methods, miR-16-5p and miR-19b-3p in plasma were found to be capable of distinguishing normal population from GC cases with different TNM stages and differentiation grades, particularly including the early
cancer cases (P<0.05). And the two
miRNAs were down-regulated in GC cases (FC<0.5). Especially, the down-regulation degree was correlated with the progression of the GC cases from the early stage to the advanced stage (0.2< r s<0.3, P<0.01). And the same weak down-regulation of the two
biomarkers as the early GC occurred initially in the precancerous diseases (P<0.05). The corresponding performance of the two
miRNAs to detect GC in ROC analysis gradually performed better with the
disease progression from the earlier stages or lower grades to the advanced stages (TNM Ⅳ stage: AUC=0.832 for miR-16-5p; TNM Ⅲ stage: AUC=0.822 for miR-19b-3p) or high grade (Poorly differentiated: AUC=0.801, 0.791 respectively for miR-16-5p and miR-19b-3p). Additionally, miR-19b-3p remained down-regulated in patient plasma within 9 days after
gastrectomy. In conclusion, miR-19b-3p and miR-16-5p maybe prospective
biomarkers to detect
gastric cancer and indicate its progression, and thus may own great potential in applications such as early screening and progression evaluation of
gastric cancer in the near future.