Related Experiment Videos
Drug resistance modification using pulsing electromagnetic field stimulation for multidrug resistant mouse
M Hirata1, K Kusuzaki, H Takeshita
1Department of Orthopaedic Surgery, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto, Japan.
Abstract:
Multidrug resistance (MDR) is one of the major problems in osteosarcoma chemotherapy. Therefore, methods of overcoming MDR are urgently needed. In this study, we investigated the effects of pulsing electromagnetic field stimulation (PEMFs) on a MDR murine osteosarcoma cell line which strongly expresses P-glycoprotein (P-gp). To assess the reversal effects of PEMFs on doxorubicin (DOX) resistance, MTT assay was applied. Viable cells were assessed by the trypan blue exclusion test. Fluorescence intensity of DOX binding to nuclear DNA of each cell was measured using a cytofluorometer. Changes in P-gp expression in each cell were detected by the indirect immunofluorescence method using an antibody to Pgp. PEMFs increased DOX binding ability to nuclear DNA and inhibited cell growth, although it had no significant effect on P-gp expression. These findings indicated that PEMFs reversed the DOX resistance of the MOS/ADR1 cells by inhibiting P-gp function. The results suggested that PEMFs may be useful as a local treatment for MDR osteosarcoma.
Insights
Pulsing electromagnetic fields (PEMFs) can overcome doxorubicin resistance in osteosarcoma by inhibiting P-glycoprotein (P-gp) function, not expression. This suggests PEMFs may be a novel local treatment for multidrug-resistant osteosarcoma.
Area of Science:
- Oncology
- Biophysics
- Biochemistry
Background:
- Multidrug resistance (MDR) poses a significant challenge in osteosarcoma chemotherapy.
- P-glycoprotein (P-gp) is a key mediator of MDR in osteosarcoma, limiting treatment efficacy.
- Novel strategies are needed to overcome P-gp-mediated drug resistance.
Purpose of the Study:
- To investigate the potential of pulsing electromagnetic field stimulation (PEMFs) to reverse doxorubicin (DOX) resistance in a MDR osteosarcoma cell line.
- To determine the effect of PEMFs on P-gp expression and function in osteosarcoma cells.
- To assess the impact of PEMFs on DOX uptake and cytotoxicity.
Main Methods:
- Utilized a P-gp overexpressing MDR murine osteosarcoma cell line (MOS/ADR1).
- Assessed cell viability and proliferation using MTT assay and trypan blue exclusion test.
- Quantified intracellular DOX fluorescence intensity using flow cytometry.
- Detected P-gp expression levels via indirect immunofluorescence.
Main Results:
- PEMFs significantly increased the binding ability of DOX to nuclear DNA in MDR osteosarcoma cells.
- PEMFs demonstrated an inhibitory effect on the proliferation of MDR osteosarcoma cells.
- PEMFs did not significantly alter the expression levels of P-gp.
- PEMFs effectively reversed DOX resistance by inhibiting P-gp function, not by reducing P-gp expression.
Conclusions:
- PEMFs can overcome doxorubicin resistance in osteosarcoma cells by modulating P-gp function.
- PEMFs represent a promising therapeutic approach for enhancing chemotherapy efficacy in multidrug-resistant osteosarcoma.
- Further research into PEMFs as a local treatment modality for MDR osteosarcoma is warranted.