Prognostic value of low microRNA-34a expression in human gastrointestinal cancer: a systematic review and meta-analysis

BMC Cancer. 2021 Jan 14;21(1):63. doi: 10.1186/s12885-020-07751-y.


Background: Mounting evidence shows that microRNA-34a (miR-34a) is involved in cancer prognosis. Therefore, we summarize the predictive role of miR-34a for survival in patients with gastrointestinal cancers (GICs).

Methods: All eligible studies were found by searching PubMed, Web of Science and EMBASE, and survival results were extracted. Then, the hazard ratio (HR) with the corresponding 95% confidence interval (CI) was calculated to evaluate the prognostic role of miR-34a in GICs. The association between miR-34a expression and clinicopathological characteristics was estimated by odds ratios (ORs) and 95% CIs.

Results: A total of 20 studies were included in this meta-analysis. For overall survival (OS), lower miR-34a expression could probably predict poorer outcome in GICs, with a pooled HR of 1.86 (95% CI: 1.52-2.28, P < 0.01). For disease-free survival (DFS), progression-free survival (PFS), and recurrence-free survival (RFS), lower miR-34a expression was related to worse DFS/PFS/RFS with a pooled HR of 1.86 (95% CI: 1.31-2.63, P < 0.01). A significant relation of differentiation/TNM stage/lymphatic metastasis and the expression level of miR-34a was identified.

Conclusion: This meta-analysis revealed that lower miR-34a expression is significantly connected with worse OS and DFS/PFS/RFS in GIC patients. In addition, the miR-34a expression level is relatively lower in patients with lymph node metastasis than in patients without lymph node metastasis, and decreased miR-34a expression levels are linked to poor tumour differentiation and late TNM stage. MiR-34a may become a new factor for the prognosis prediction and progression of GICs.

Keywords: Gastrointestinal cancer; Meta-analysis; Prognosis; microRNA-34a.

Publication types

  • Meta-Analysis
  • Systematic Review

MeSH terms

  • Biomarkers, Tumor / genetics*
  • Biomarkers, Tumor / metabolism
  • Gastrointestinal Neoplasms / genetics
  • Gastrointestinal Neoplasms / metabolism
  • Gastrointestinal Neoplasms / pathology*
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • MicroRNAs / genetics*
  • MicroRNAs / metabolism
  • Prognosis


  • Biomarkers, Tumor
  • MIRN34 microRNA, human
  • MicroRNAs