Research Uncovers Mechanism in Metformin
A common diabetes drug may have another use in the treatment of cancer. Usually used to manage insulin, metformin may have the potential to help patients with cancer by delaying tumor growth.
Many people use metformin to treat type II diabetes. Recent studies have suggested that the anti-diabetic drug prevents cancer progression, but how metformin diminishes tumor growth is not fully understood. When used to treat diabetes, metformin decreases insulin in the blood, so some scientists believe this effect may be what is responsible for slowing tumor growth.
To further understand the mechanism that could inhibit the development of cancer, Northwestern Medicine scientists studied the effects of metformin on cancer cells. Using tissue cultures and mouse models, a team led by Navdeep S. Chandel, PhD, professor in Medicine-Pulmonary and Cell and Molecular Biology, measured oxygen consumption and tumor growth.
Chandel and his collaborators showed that metformin acts through mitochondrial complex I, a compound that is central to energy production in cells. When metformin disrupts mitochondrial complex I, it prevents the necessary insulin energy from reaching the cancer cells and slows tumor growth. The scientists discovered that the drug worked specifically through pathways meant to help cells survive low-oxygen conditions. As a result, metformin has the ability to slow down cancer development when too much glucose is present. Ultimately, the drug can kill cancer cells entirely when they are deprived of glucose.
The Northwestern Medicine team’s findings suggest that metformin may be able to slow down tumor progression when used alongside other therapies. The study has effectively provided a tool to explore how the diabetes drug may be able to work in combination with other cancer treatments.