Related Experiment Video
Updated: Jul 15, 2025
Studying Pancreatic Cancer Stem Cell Characteristics for Developing New Treatment Strategies
Published on: June 20, 2015
The Effect of Different Glucose Concentrations on the Antiproliferative Activity of Metformin in MCF-7 Breast Cancer
Sholpan Nurzhan1,2, Zhibek Bekezhankyzy1,2, Hong Ding3
1Department of Biomedical Sciences, School of Medicine, Nazarbayev University, Astana Z05H0P9, Kazakhstan.
Abstract:
The glucose-lowering drug metformin has been reported to have anticancer properties through unknown mechanisms. Other unknown factors that may influence its anticancer potential include the glycemic status of the patient. Therefore, the objective of this study is to determine the effect of different glucose environments on the antiproliferative potency and the cellular mechanism of action of metformin. Human breast cancer cells, MCF-7, were incubated in low, normal, elevated, and high glucose environments and treated with metformin. The antiproliferative potential of metformin and its effect on protein expression as well as its ability to induce cellular apoptosis and autophagy under different glucose environments, were determined using different molecular techniques. Metformin significantly inhibited cellular proliferation in a time- and glucose-concentration-dependent manner. In comparison to elevated glucose, low normal glucose alone induced a significant level of autophagy that was further increased in the presence of metformin. While glucose concentration did not appear to have an effect on the antiproliferative potency of metformin, the cellular basis of action was shown to be glucose-dependent. The antiproliferative mechanism of action of metformin in elevated and low normal glucose environments is mTOR-dependent, whereas, in the high glucose environment, the antiproliferative mechanism is independent of mTOR. This is the first study to report that both the antiproliferative potency and the cellular mechanism of action aredependent on the concentration of glucose.
Insights
Metformin
Area of Science:
- Oncology
- Endocrinology
- Molecular Biology
Background:
- Metformin, a glucose-lowering drug, exhibits anticancer properties via unknown mechanisms.
- Patient glycemic status may influence metformin's anticancer potential.
- The precise cellular mechanisms underlying metformin's effects require further elucidation.
Purpose of the Study:
- To investigate the impact of varying glucose concentrations on metformin's antiproliferative efficacy.
- To determine how different glucose environments affect metformin's cellular mechanism of action.
- To explore the relationship between glucose levels, autophagy, apoptosis, and mTOR signaling in response to metformin.
Main Methods:
- Incubation of human breast cancer cells (MCF-7) in distinct glucose environments (low, normal, elevated, high).
- Treatment of cells with metformin and assessment of antiproliferative effects.
- Analysis of protein expression, apoptosis, and autophagy induction using molecular techniques.
- Investigation of the mechanistic role of mTOR signaling pathway.
Main Results:
- Metformin demonstrated significant inhibition of cancer cell proliferation in a time- and glucose-dependent manner.
- Low and normal glucose environments, particularly with metformin, significantly induced autophagy.
- Metformin's antiproliferative potency was not significantly affected by glucose concentration.
- The cellular mechanism of action was glucose-dependent, involving mTOR in elevated/normal glucose but not in high glucose.
Conclusions:
- Glucose concentration plays a critical role in modulating the cellular mechanisms of metformin's antiproliferative action.
- Metformin's anticancer effects are influenced by the cellular glucose environment, impacting pathways like mTOR.
- This study highlights the glucose-dependent nature of both metformin's potency and its mechanism, offering insights for cancer therapy.
