Prognostic Value of Candidate MicroRNAs in Gastric Cancer: A Validation Study

Background: Studies have reported the prognostic value of dysregulated microRNAs (miRNAs) in gastric cancer (GC). However, the results demonstrated so far are inconsistent.

Objective: To better understand the miRNAs with prognostic relevance.

Methods: Evaluable miRNAs were selected based on our selection criteria and further analyzed in formalin-fixed paraffin-embedded (FFPE) tissue samples of 169 GC patients using quantitative real-time polymerase chain reaction (qRT-PCR).

Results: A total of 19 miRNAs were selected as candidate miRNAs. Among those miRNAs identified, high expression of miR-21-5p was related to poor overall survival (OS) and disease free survival (DFS) and was identified as an independent prognostic factor. Cases with high level of miR-200c-3p showed poor DFS. Subgroup analysis revealed that high expression of miR-21-5p and miR-222-3p was associated with poor OS and DFS in GC patients not received adjuvant chemotherapy. In male patients, high expression level of miR-21-5p was related to poor OS and DFS.

Conclusions: The present study confirmed that elevated level of miR-21-5p could serve as an independent predictor for poor OS and DFS of GC patients. Moreover, miR-200c-3p, miR-222-3p might also play important roles in the prognosis of GC patients. Further studies are warranted to validate our findings and identify the functions and mechanisms of these miRNAs.