Published online Feb 14, 2022. doi: 10.3748/wjg.v28.i6.653
Peer-review started: September 13, 2021
First decision: November 16, 2021
Revised: November 19, 2021
Accepted: January 19, 2022
Article in press: January 19, 2022
Published online: February 14, 2022
Processing time: 148 Days and 14.2 Hours
Gastric cancer (GC) is one of the most frequently diagnosed tumor globally. In most cases, GC develops in a stepwise manner from chronic gastritis or atrophic gastritis (AG) to cancer. One of the major issues in clinical settings of GC is diagnosis at advanced disease stages resulting in poor prognosis. MicroRNAs (miRNAs) are small noncoding molecules that play an essential role in a variety of fundamental biological processes. However, clinical potential of miRNA profiling in the gastric cancerogenesis, especially in premalignant GC cases, remains unclear.
To evaluate the AG and GC tissue miRNomes and identify specific miRNAs’ potential for clinical applications (e.g., non-invasive diagnostics).
Study included a total of 125 subjects: Controls (CON), AG, and GC patients. All study subjects were recruited at the Departments of Surgery or Gastroenterology, Hospital of Lithuanian University of Health Sciences and divided into the profiling (n = 60) and validation (n = 65) cohorts. Total RNA isolated from tissue samples was used for preparation of small RNA sequencing libraries and profiled using next-generation sequencing (NGS). Based on NGS data, deregulated miRNAs hsa-miR-129-1-3p and hsa-miR-196a-5p were analyzed in plasma samples of independent cohort consisting of CON, AG, and GC patients. Expression level of hsa-miR-129-1-3p and hsa-miR-196a-5p was determined using the quantitative real-time polymerase chain reaction and 2-ΔΔCt method.
Results of tissue analysis revealed 20 differentially expressed miRNAs in AG group compared to CON group, 129 deregulated miRNAs in GC compared to CON, and 99 altered miRNAs comparing GC and AG groups. Only 2 miRNAs (hsa-miR-129-1-3p and hsa-miR-196a-5p) were identified to be step-wise deregulated in healthy-premalignant-malignant sequence. Area under the curve (AUC)-receiver operating characteristic analysis revealed that expression level of hsa-miR-196a-5p is significant for discrimination of CON vs AG, CON vs GC and AG vs GC and resulted in AUCs: 88.0%, 93.1% and 66.3%, respectively. Compar-ing results in tissue and plasma samples, hsa-miR-129-1-3p was significantly down-regulated in GC compared to AG (P = 0.0021 and P = 0.024, tissue and plasma, respectively). Moreover, analysis revealed that hsa-miR-215-3p/5p and hsa-miR-934 were significantly deregulated in GC based on Helicobacter pylori (H. pylori) infection status [log2 fold change (FC) = -4.52, P-adjusted = 0.02; log2FC = -4.00, P-adjusted = 0.02; log2FC = 6.09, P-adjusted = 0.02, respectively].
Comprehensive miRNome study provides evidence for gradual deregulation of hsa-miR-196a-5p and hsa-miR-129-1-3p in gastric carcinogenesis and found hsa-miR-215-3p/5p and hsa-miR-934 to be significantly deregulated in H. pylori carrying GC patients.
Core Tip: In this research we aimed to evaluate microRNAs profiles of premalignant and malignant stages of gastric cancer (GC). To date this is the first study analyzing atrophic gastritis (AG) and GC tissue miRNomes in the subjects of European origin using next-generation sequencing approach. We showed that hsa-miR-196a-5p expression in tissue is significant for discrimination between controls and AG or GC, while hsa-miR-129-1-3p is potential candidate for non-invasive GC diagnostic. This study provides novel insights into complex GC pathogenesis cascade and might be highly significant for future studies of new AG or GC associated epigenetic markers or even diagnostic targets.