The Value of MicroRNA-155 as a Prognostic Factor for Survival in Non-Small Cell Lung Cancer: A Meta-Analysis

Background
Recent studies have shown that miR-155 play a positive role in the development of carcinoma. This meta-analysis aimed to identify the role of miR-155 in the survival of non-small cell lung cancer patients.
Methodology
Eligible studies were identified through database searches. Relevant data were extracted from each eligible study to assess the correlation between miR-155 expression and survival in lung carcinoma patients. The hazard ratios (HRs) and 95% confidence intervals (CIs) of the patients’ outcomes in relation to miR-155 were calculated. A total of 6 studies were included for this meta-analysis. For overall survival (OS), recurrence-free survival (RFS), disease-free survival (DFS), and cancer-specific survival (CSS), the combined HRs and 95% CIs were not statistically significant. Additionally, in Asian and America subgroups, greater expression levels of miR-155 were related to poor prognoses for lung cancer (HR 1.71 95% CI: 1.22–2.40, P = 0.002, HR 2.35 95% CI: 1.42–3.89 P = 0.001), while no significant relationship was present in a Europe subgroup (HR 0.75 95%CI: 0.27–2.10, P = 0.587).
Conclusions
These results suggest that miR-155 expression is not significantly related to non-small cell lung cancer patients except in patients from Asian and America.