Serum exosomal miR-122-5p, GAS, and PGR in the non-invasive diagnosis of CAG

OBJECTIVE: The aim of this study was to integrate the serum exosomal miRNA miR-122-5p with canonical serological biomarkers for the non-invasive screening of chronic atrophic gastritis (CAG) patients. METHODS: miR-122-5p and U6 were amplified by the quantitative reverse transcription polymerase chain reaction (RT-qPCR), gastrin (GAS), pepsinogen I (PG-I), and PG-II and were measured by ELISA. The area under the receiver operating characteristic (ROC) curves and their correlation were analyzed. RESULTS: In the present study, GAS level and PG-I/PG-II ratio (PGR) were increased in CAG group, but there was no significant difference in PG-I or PG-II levels between CAG group and chronic non-atrophic gastritis (CNAG) group. Only GAS level and PG-I/PG-II ratio were significantly correlated with atrophy, and not any other clinicopathologic factors. Expression of hsa-miR-122-5p positively correlated with GAS level, PG-I level, and PGR, while it negatively correlated with PG-II level; however, none of them had significant difference. The combination of GAS, PGR, and hsa-miR-122-5p presented as a better model for non-invasive screening of CAG compared to others. CONCLUSION: These results suggested that serum exosomal hsa-miR-122-5p combined with GAS and PGR would elevate accuracy and specificity in non-invasive screening of CAG.