Researchers are hopeful that the oral anti-diabetic metformin (biguanide),
a safe and low cost drug, is showing positive signs of being used in the treatment of cancer.
Biguanides are commonly prescribed for the treatment of hyperglycemia and type 2 diabetes. The potential of metformin in cancer treatment was first established in epidemiological studies of diabetic patients who had cancer. In the recent studies, it was demonstrated that metformin may also target and inhibit cancer-initiating cells in the tumor.
The anticancer effects of biguanide are associated with both indirect (insulin-dependent)
and direct (insulin independent)
actions of the drug.
In a recent study lead by Dr Ryan J O Dowling of Ontario Cancer Institute at University Health Network, Canada, the epidemiological, preclinical, and clinical evidences all gives a green signal for the use of metformin as an anticancer drug.
The competence of metformin to lower the circulating insulin can be important for the treatment of cancers (such as those originating from the of the breast and colon). which are known to be associated with hyper- insulinemia (increasd insulin secretion) However, there is also a probability of metformin exhibiting direct inhibitory effects on cancerous cells by suppressing mammalian target of rapamycin (mTOR) signaling and protein synthesis.
Overall the clinical safety, a dependable pharmaco-dynamic profile, and low cost of metformin make it an ideal candidate to be developed as a potential anticancer agent. Reference