Metformin - a new star in cancer treatment?

Metformin, an oral biguanide antidiabetic drug, is the most widely prescribed agent for treatment of type 2 diabetes. The drug mainly

works by lowering glucose production by the liver, and thus lowering fasting blood glucose. Metformin acts as an insulin sensitizer,

which leads to inhibition of gluconeogenesis in the liver, and has been found to be beneficial especially in overweight patients with

diabetes. Metformin use has been postulated to contribute to a reduced risk of pancreatic, prostate, ovarian, and breast cancers. Metformin‘

s mechanism of action was examined recently and determined to be initiated by metformins role as an adenosine 5‘-mono-phosphate–

activated protein kinase (AMPK) activator through a tumor suppressor protein kinase known as LKB-1, which regulates AMPK

levels. Activation of AMPK has been shown to suppress the mammalian target of the rapamycin (mTOR) signaling pathway, leading to

antiproliferative and antiangiogenic effects.

Keywords: cancer, diabetes mellitus, metformin, mTOR, AMPK