These new findings could potentially guide researchers as they continue to explore the use of existing medications to treat new or different diseases.
Metformin's Many UsesMetformin is a commonly prescribed drug to treat diabetes. Earlier studies have shown it may be effective for other cancers and the currently study verifies this hypothesis.
Research presented earlier this year at the American Association for Cancer Research Meeting 2012, revealed that metformin can successfully increase survival rates for patients with early-stage pancreatic cancer, slow prostate cancer growth, and help prevent primary liver cancer.. The presenters noted that metformin's anti-cancer properties may also benefit patients with oral cancer, as well as those with some forms of melanoma.
A study led by researchers at the Spanish National Cancer Research Centre in Madrid, showed metformin combined with chemotherapy eliminated cancer stem cells as well as more differentiated cancer cells that form the majority of the tumors in pancreatic cancer patients. The research team found support for their findings through an experiment using mice with patient-derived tumors as subjects, finding when treated with a combination of metformin and chemotherapy, the mice had decreased tumors and showed a reduction in relapse in comparison to the group of mice who received different therapy.
In regards to lung cancer, research from 2010 showed that metformin can inhibit the progression, improve survival rates, and even reduce risk for advanced stage lung cancer in patients with diabetes and lung cancer. The study also revealed that metformin may even be more effective than TZDs (thiazolidinediones) and could eventually be made a part of standard treatment for lung cancer.
Similar Findings for Ovarian CancerThe investigators, headed by the Mayo Clinic, analyzed the survival rates of 61 patients with ovarian cancer taking metformin, and 178 patients who did not take metformin. Of the participants who took metformin, sixty-seven percent of them continued to live after five years. On the other hand, only forty-seven percent of the participants who did not take metformin survived.
Factors taken under consideration included:
- body mass index
- type of chemotherapy
- the severity of the cancer
- quality of surgery
Co-author Sanjeev Kumar, M.B.B.S., a Mayo Clinic gynecologic oncology fellow says:
"Our study demonstrated improved survival in women with ovarian cancer that were taking metformin. The results are encouraging, but as with any retrospective study, many factors cannot be controlled for us to say if there is a direct cause and effect. Rather, this is further human evidence for a potential beneficial effect of a commonly used drug which is relatively safe in humans. These findings should provide impetus for prospective clinical trials in ovarian cancer."
The findings may lead the way for using metformin in bigger, randomized studies of ovarian cancer. Because of the increased rate of death for ovarian cancer, the authors explain that there is a strong requirement to come up with new therapies to treat this cancer. Metformin could be one of these choices.