Related Experiment Video
Updated: Sep 26, 2025
Bacterial Delivery of RNAi Effectors: Transkingdom RNAi
Published on: August 18, 2010
miR-205 Reverses MDR-1 Mediated Doxorubicin Resistance via PTEN in Human Liver Cancer HepG2 Cells
Mei Li1, Z Hubin Li1, Juanrong Song1
1Department of Minimally Invasive Intervention, Shaanxi Provincial Cancer Hospital, Xi'an, Shaanxi, China.
Objective:
The aim of the recent study was to investigate the effects of miR-205 on reversing Doxorubicin (DOX) resistance, as chemotherapeutic agents through up-regulation of PTEN in human liver cancer HepG2 cells.
Materials And Methods:
In this experimental study, the drug resistance in liver cancer cells via drug efflux inhibition and enhancing apoptosis by the regulation of PTEN and multi-drug resistance/ P-glycoprotein (MDR/P-gp) expression was revealed. Using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, effect of DOX on cell proliferation was evaluated after miR-205 transfection in HepG2 and HepG2/DOX cells. Activity of P-gp on drug efflux was measured by the Rhodamine 123 (Rho-123) assay. PTEN mRNA expression levels were measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and flow cytometry was used to measure the apoptotic ratio of HepG2/DOX cells.
Results:
miR-205 overexpression considerably inhibited the HepG2/DOX cells viability (P<0.05). qRT-PCR results revealed that PTEN is a pivotal regulator in PI3K/Akt/P-gp axis. Overexpression miR-205 resulted in up-regulation PTEN and ultimately down-regulation of P-gp. This inhibits drug resistance, proliferation and induces apoptosis in HepG2/DOX cells (P<0.05). Whilst, treatment with 10 μM of special inhibitors, including LY294002 (PI3K) or PD098059 (MAPK), increased Rho 123-associated MFI, treatment with 10 μM of SF1670 (PTEN) almost abolished the effect of miR-205 overexpression (P<0.05). Finally, we found that miR-205 was down-regulated in HepG2/DOX cells, and its overexpression led to enhancing apoptosis with re-sensitization of HepG2/DOX cell lines to DOX through PTEN/PI3K/ Akt/MDR1 pathway.
Conclusion:
These findings may introduce miR-205 as a predictive biomarker and a potential treatment target for liver cancer therapy during MDR.
Insights
MicroRNA-205 (miR-205) can reverse Doxorubicin resistance in liver cancer by up-regulating PTEN, inhibiting P-glycoprotein, and enhancing apoptosis. This study highlights miR-205 as a potential therapeutic target for overcoming multi-drug resistance in liver cancer.
Area of Science:
- Oncology
- Molecular Biology
- Biochemistry
Background:
- Hepatocellular carcinoma (HCC) is a major global health concern with limited treatment options.
- Doxorubicin (DOX) is a common chemotherapeutic agent, but its efficacy is often limited by the development of multi-drug resistance (MDR).
- Understanding the molecular mechanisms underlying DOX resistance is crucial for developing effective cancer therapies.
Purpose of the Study:
- To investigate the role of microRNA-205 (miR-205) in reversing Doxorubicin resistance in human liver cancer HepG2 cells.
- To explore the potential of miR-205 as a therapeutic agent by examining its effects on PTEN, P-glycoprotein (P-gp), and apoptosis.
- To elucidate the molecular pathway involved in miR-205-mediated reversal of drug resistance.
Main Methods:
- Cell viability was assessed using the MTT assay in HepG2 and HepG2/DOX cells following miR-205 transfection.
- Drug efflux activity of P-gp was measured using the Rhodamine 123 (Rho-123) assay.
- PTEN mRNA expression was quantified using qRT-PCR, and apoptosis was analyzed by flow cytometry.
Main Results:
- Overexpression of miR-205 significantly inhibited HepG2/DOX cell viability and induced apoptosis.
- miR-205 overexpression led to increased PTEN expression and decreased P-gp expression, thereby inhibiting drug efflux.
- The PTEN/PI3K/Akt/MDR1 pathway was identified as the key mechanism through which miR-205 re-sensitizes liver cancer cells to DOX.
Conclusions:
- miR-205 plays a critical role in overcoming Doxorubicin resistance in liver cancer by targeting the PTEN/PI3K/Akt/MDR1 pathway.
- Down-regulation of miR-205 was observed in DOX-resistant HepG2 cells.
- miR-205 holds promise as a predictive biomarker and a potential therapeutic target for liver cancer patients with multi-drug resistance.
More Related Videos
14:51Pooled shRNA Library Screening to Identify Factors that Modulate a Drug Resistance Phenotype
Published on: June 17, 2022
10:59Conditional Knockdown of Gene Expression in Cancer Cell Lines to Study the Recruitment of Monocytes/Macrophages to the Tumor Microenvironment
Published on: November 23, 2017