DIAGNOSTIC AND PROGNOSTIC POTENTIAL OF CIRCULATING microRNAS miR-1301-3p, miR-106A-5p, miR-129-5p, miR-3613-3p, miR-647 IN GASTRIC CANCER

Gastric cancer (GC) is one of the most common malignant tumors worldwide and ranks fifth in the structure of cancer mortality. MicroRNAs are involved in the pathogenesis and progression of GC as epigenetic factors, and are considered as potential noninvasive markers. We selected microRNAs involved in the regulation of epigenetic mechanisms in GC (miR-1301-3p, miR-106a-5p, miR-129-5p, miR-3613-3p, miR-647) and analyzed their expression in plasma of GC patients. To assess their diagnostic and prognostic potential, we estimated correlations of differential expression with the clinical and pathological characteristics of GC tumors. The study included 65 plasma samples from GC patients and 48 plasma samples obtained from individuals without tumor lesions, which were used as a control group. The expression was analyzed by using the reverse transcription polymerase chain reaction (RT-PCR) method. When comparing the expression levels of selected microRNAs in the plasma of GC patients and the control group, significant differences were found for miR-1301-3p (p = 0.04), miR-106a-5p (p = 0.029), miR-129-5p (p < 0.0001), miR-647 (p < 0.0001). MiR-129-5p expression was significantly associated with the prevalence of a primary tumor (p = 0.002), with the development of metastases to regional lymph nodes (p = 0.003) and distant metastases (p = 0.003), as well as a late clinical stage (p = 0.003). There was a significant correlation between miR-3613-3p expression and the clinical stage of GC (p = 0.049). ROC analysis revealed that combining miR-106a-5p, miR-129-5p, miR-1301-3p and miR-647 improves the diagnostic and prognostic properties of a potential panel of markers.