MicroRNA-218 Increases the Sensitivity of Bladder Cancer to Cisplatin by Targeting Glut1

Cell Physiol Biochem. 2017;41(3):921-932. doi: 10.1159/000460505. Epub 2017 Feb 20.


Background/aims: MicroRNA-218 (miR-218) is down-regulated in many malignancies that have been implicated in the regulation of diverse processes in cancer cells. However, the involvement of miR-218 in chemo-sensitivity to cisplatin and the precise mechanism of this action remained unknown in bladder cancer.

Methods: qRT-PCR was used to detect miR-218 and its target Glut1 expression in bladder cancer cell lines T24 and EJ. CCK-8 method was utilized to measure the cell viability. IC 50 was calculated via a probit regression model. Glut1 was detected by western blotting for analysis of potential mechanism. Luciferase reporter assay was utilized to validate Glut1 as a direct target gene of miR-218. The intracellular level of GSH and ROS were determined using a commercial colorimetric assay kit and 2', 7'-dichlorodihydro-fluorescein diacetate, respectively.

Results: Over-expression of miR-218 significantly reduced the rate of glucose uptake and total level of GSH and enhanced the chemo-sensitivity of bladder cancer to cisplatin. Mechanistically, Glut1 was found to be a direct and functional target of miR-218. Up-regulation of Glut1 could restore chemo-resistance in T24 and EJ cells. On the contrary, knockdown of Glut1 could generate a similar effect as up-regulating the expression of miR-218.

Conclusions: MiR-218 increases the sensitivity of bladder cancer to cisplatin by targeting Glut1. Restoration of miR-218 and repression of glut1 may provide a potential strategy to restore chemo-sensitivity in bladder cancer.

Keywords: Bladder cancer; Chemo-sensitivity; Cisplatin; Glut1; MiR-218.

MeSH terms

  • Antineoplastic Agents / pharmacology*
  • Base Sequence
  • Binding Sites
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Cisplatin / pharmacology*
  • Epithelial Cells / drug effects*
  • Epithelial Cells / metabolism
  • Epithelial Cells / pathology
  • Gene Expression Regulation, Neoplastic*
  • Genes, Reporter
  • Glucose / antagonists & inhibitors
  • Glucose / metabolism
  • Glucose Transporter Type 1 / antagonists & inhibitors
  • Glucose Transporter Type 1 / genetics*
  • Glucose Transporter Type 1 / metabolism
  • Glutathione / agonists
  • Glutathione / metabolism
  • Humans
  • Inhibitory Concentration 50
  • Luciferases / genetics
  • Luciferases / metabolism
  • MicroRNAs / agonists
  • MicroRNAs / genetics*
  • MicroRNAs / metabolism
  • Signal Transduction
  • Urinary Bladder / drug effects
  • Urinary Bladder / metabolism
  • Urinary Bladder / pathology


  • Antineoplastic Agents
  • Glucose Transporter Type 1
  • MIRN218 microRNA, human
  • MicroRNAs
  • SLC2A1 protein, human
  • Luciferases
  • Glutathione
  • Glucose
  • Cisplatin