Previous studies have shown that metformin has some anti-proliferative activity against multiple types of cancer cells. Moreover, clinical meta-analysis studies on cancer patients who already take metformin to treat diabetes have hinted that the drug may boost their survival and prevent the emergence of new tumors.
‘Metformin, was found to have an anti-proliferative effect on widely studied breast cancer cell line MCF7, including cells that were also resistant to the common chemotherapeutic Doxorubicin’
Arnason and colleagues probed the effect of metformin on the widely studied breast cancer cell line MCF7. Metformin, they found, had an anti-proliferative effect on MCF7, including cells that were resistant to the common chemotherapeutic Doxorubicin.
When cells were pre-treated with metformin, the development of drug resistance was prevented or delayed. In addition, experiments conducted in both cell cultures and mouse models of aggressive breast cancer revealed that metformin reversed protein markers associated with MDR after its onset.
These findings establish that metformin has the potential to both reverse MDR in cell lines and prevent its onset. Future research will need to extend the timeline of the study to follow cancer cells for many months and determine if the effect of metformin is permanent or short-lived.