MiR-218 produces anti-tumor effects on cervical cancer cells in vitro

World J Surg Oncol. 2018 Oct 12;16(1):204. doi: 10.1186/s12957-018-1506-3.


Background: As indoleamine-2,3-dioxygenase 1 (IDO1) is critical in tumor immune escape, we determined to study the regulatory mechanism of miR-218 on IDO1 in cervical cancer.

Methods: Real-time PCR (RT-qPCR) was carried out to measure the expression of miR-218. RT-qPCR and Western blot were performed to detect the expression of IDO1 in cervical cancer. Dual-luciferase reporter assay was used to determine the binding of miR-218 on the IDO1 3'UTR. Cell viability, apoptosis, and related factors were determined using cell counting kit-8 (CCK-8), Annexin-V/PI (propidium) assay, enzyme-linked immunosorbnent assay (ELISA), RT-qPCR, and Western blot assays after miR-218 mimics has been transfected to HeLa cervical cancer cells.

Results: MiR-218 was downregulated in cervical cancer. The expression of miR-218 was negatively correlated with IDO1 in cervical cancer tissues and cells. IDO1 is a direct target of miR-218. MiR-218 overexpression was found to inhibit cell viability and promoted apoptosis via activating the expression of Cleaved-Caspase-3 and to inhibit the expression of Survivin, immune factors (TGF-β, VEGF, IL-6, PGE2, COX-2), and JAK2/STAT3 pathway.

Conclusion: MiR-218 inhibits immune escape of cervical cancer cells by direct downregulating IDO1.

Keywords: Apoptosis; Cervical cancer; IDO1; Immune escape; JAK2/STAT3; MiR-218.

MeSH terms

  • Adult
  • Apoptosis*
  • Cell Proliferation
  • Female
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • In Vitro Techniques
  • Indoleamine-Pyrrole 2,3,-Dioxygenase / genetics
  • Indoleamine-Pyrrole 2,3,-Dioxygenase / metabolism*
  • MicroRNAs / genetics*
  • Middle Aged
  • Prognosis
  • Tumor Cells, Cultured
  • Uterine Cervical Neoplasms / genetics
  • Uterine Cervical Neoplasms / metabolism
  • Uterine Cervical Neoplasms / pathology*
  • Young Adult


  • IDO1 protein, human
  • Indoleamine-Pyrrole 2,3,-Dioxygenase
  • MIRN218 microRNA, human
  • MicroRNAs