MicroRNA-218 Increases the Sensitivity of Bladder Cancer to Cisplatin by Targeting Glut1
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.
Insights
MicroRNA-218 enhances bladder cancer chemo-sensitivity to cisplatin by targeting Glut1. Restoring miR-218 and repressing Glut1 may improve treatment strategies.
Area of Science:
- Oncology
- Molecular Biology
- Biochemistry
Background:
- MicroRNA-218 (miR-218) is frequently downregulated in various cancers.
- Its role in bladder cancer chemo-sensitivity and underlying mechanisms remain unclear.
Purpose of the Study:
- To investigate the role of miR-218 in bladder cancer chemo-sensitivity to cisplatin.
- To elucidate the precise molecular mechanism involving miR-218 and its targets.
Main Methods:
- Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) for miR-218 and Glut1 expression.
- Cell viability assays (CCK-8) and IC50 calculation.
- Western blotting, luciferase reporter assays, and measurement of intracellular GSH and ROS levels.
Main Results:
- Overexpression of miR-218 increased cisplatin chemo-sensitivity in bladder cancer cells.
- Glut1 was identified as a direct target of miR-218, mediating glucose uptake and GSH levels.
- Modulating Glut1 expression inversely affected chemo-resistance, confirming its role in the miR-218 pathway.
Conclusions:
- MiR-218 enhances bladder cancer chemo-sensitivity to cisplatin by directly targeting Glut1.
- Restoring miR-218 or repressing Glut1 presents a potential therapeutic strategy for overcoming chemo-resistance.
