Analysis of plasma MicroRNAs to identifying early diagnostic molecule for gastric cancer.

Gastric cancer (GC) remains the second leading cause of cancer-related death worldwide. Owing to the lack of early diagnostic techniques, GC is often diagnosed at advanced stage and that leading to low survival rate. Growing evidences have been suggesting that circulating microRNAs play an important role in earlier diagnostic of disease. In the present study, we analyze the circulating miRNAs expression in plasma of volunteers with/without GC aiming to identifying early diagnostic biomarkers. Plasma samples were collected form 6 volunteers including 3 early patients with GC and 3 healthy adults. And then miRNAs microarrays were performed to detect the expression profile of miRNAs in these plasma samples. For further validate the results from miRNAs microarray, qRT-PCR was performed. Finally, target genes of miRNAs were predicted by bioinformatic means. Compared to control plasma, 11 up-regulated and 13 down-regulated miRNAs were detected in the plasma from earlier patients with GC (fold change ≥ 2, P < 0.05). Then, 5 differential expression miRNAs (miR-223, miR-19b-2*, miR-194*, miR-141, miR-1233) were chose to confirm by qRT-PCR. The result is nearly consistent with previous data from miRNAs microarray. Finally, 53 target genes of the 5 miRNAs are predicted by bioinformatics. These differential expression miRNAs may be used as biomarker candidates for minimally invasive diagnosis of early patients with GC in the future.