Six Serum-Based miRNAs as Potential Diagnostic Biomarkers for Gastric Cancer.

BACKGROUND: Circulating miRNAs in serum may serve as promising diagnostic biomarkers for patients with gastric cancer.

METHODS: Using qRT-PCR-based Exiqon panel, we identified 58 differentially expressed miRNAs from three gastric cancer pool samples and one normal control (NC) pool in the initial screening phase. Identified miRNAs were further validated in the training (49 gastric cancer vs. 47 NCs) and validation phases (154 gastric cancer vs. 120 NCs) using qRT-PCR. The expression levels of the miRNAs were also determined in tissues, arterial serum, and exosomes.

RESULTS: Consequently, six serum miRNAs (miR10b-5p, miR132-3p, miR185-5p, miR195-5p, miR-20a3p, and miR296-5p) were significantly overexpressed in gastric cancer compared with NCs. The areas under the receiver operating characteristic curve of the six-miRNA panel were 0.764 and 0.702 for the training and validation phases, respectively. miR10b-5p and miR296-5p were significantly upregulated in gastric cancer tissues (n = 188). In addition, patients who did not receive adjuvant chemotherapy with high expression of miR10b-5p or miR296-5p in tissues tended to suffer worse overall survival. Furthermore, the expression levels of miR10b-5p, miR195-5p, miR20a-3p, and miR296-5p were significantly elevated in exosomes from gastric cancer serum samples (n = 30).

CONCLUSIONS: We identified a six-miRNA panel in serum for the detection of gastric cancer.

IMPACT: Our findings provide a novel serum miRNA signature for gastric cancer diagnosis, and will serve as the basis of the application of circulating miRNAs in clinical for the detection of gastric cancer in the future. Cancer Epidemiol Biomarkers Prev; 26(2); 188-96. ©2016 AACR.