Old drug, new trick: Repurposing metformin for gynecologic cancers?

Numerous clinical studies have reported an association between metformin use by diabetic patients and improved outcomes in gynecologic cancers. In addition, pre-clinical reports have identified plausible biological mechanisms to explain the molecular mechanism of action of metformin in cancer. However, the most important question remains unanswered: Will metformin be effective against cancer in patients without diabetes? Until this question is answered with prospective clinical testing, the role of metformin in the treatment or prevention of gynecologic malignancies remains theoretical and the clinical use of metformin as a cancer therapeutic is experimental.