By KYW Medical Editor Brian McDonough

PHILADELPHIA (CBS) – The generic diabetes drug Metformin, which has been around for years, is being studied as a possible wonder drug in the battle against cancer.

The drug Metformin is an effective medication used to fight against diabetes. It’s taken by millions of Americans.

Now there’s new information reported at the American Association for Cancer Research in Chicago that suggests that Metformin can fight against certain forms of cancer. In particular, there have been successes against prostate cancer as well as pancreatic cancer.

No one is sure why this is the case and certainly they say before people start taking it to fight cancer, we need more information. One theory is that Metformin not only decreases blood sugar level, but it also seems to have an effect on the development of cancer, perhaps by reducing the amount of circulating insulin in the blood.

Insulin can fuel the growth of prostate cancer cells.