Metformin May Lower Risk for Oral Cancer Development
New findings published in Cancer Prevention Research, a journal of the American Association for Cancer Research, suggest that metformin may protect against oral cancer.
J. Silvio Gutkind, Ph.D., chief of the Oral and Pharyngeal Cancer Branch of the National Institute of Dental and Craniofacial Research at the National Institutes of Health, and colleagues induced premalignant lesions in laboratory mice and studied the effect of metformin on progression of these lesions to oral cancers.
“We saw strong activity against mTORC1 (mammalian target of rapamycin complex 1), which we know contributes to oral cancers, so this is strong preclinical information that there is a protective effect,” said Gutkind.
Metformin is the most widely used treatment for patients with type 2 diabetes, and scientists have started to notice a trend toward cancer reduction in a number of organ sites.
Gutkind and colleagues found that administration of metformin reduced the size and number of carcinogen-induced oral tumoral lesions in mice and significantly reduced the development of squamous cell carcinomas by about 70 to 90 percent.
They found that metformin inhibited mTORC1 function in the basal layer of oral premalignancies and prevented their spontaneous development into head and neck squamous cell carcinomas.
- A diabetes medication used by millions is now showing promise against a variety of different cancers.
Two new clinical studies to be presented Saturday at the annual meeting of the American Association for Cancer Research, in Chicago, found that metformin (also known by the brand name Glucophage, among others), appeared linked to a slowing in the rate of prostate cancer growth in certain patients, and in prolonging life for early-stage pancreatic cancer patients.
Other studies, done either in the lab or in animals, also hint that the drug might have an effect against liver or oral tumors, as well as certain forms of melanoma.
“We clearly saw a direct effect on premalignant lesions,” said Gutkind.
About the AACR
Founded in 1907, the American Association for Cancer Research (AACR) is the world’s first and largest professional organization dedicated to advancing cancer research and its mission to prevent and cure cancer. AACR’s membership includes 34,000 laboratory, translational and clinical researchers; population scientists; other health care professionals; and cancer advocates residing in more than 90 countries. The AACR marshals the full spectrum of expertise of the cancer community to accelerate progress in the prevention, biology, diagnosis and treatment of cancer by annually convening more than 20 conferences and educational workshops, the largest of which is the AACR Annual Meeting with more than 18,000 attendees. In addition, the AACR publishes seven peer-reviewed scientific journals and a magazine for cancer survivors, patients and their caregivers. The AACR funds meritorious research directly as well as in cooperation with numerous cancer organizations. As the Scientific Partner of Stand Up To Cancer, the AACR provides expert peer review, grants administration and scientific oversight of individual and team science grants in cancer research that have the potential for patient benefit. The AACR actively communicates with legislators and policy makers about the value of cancer research and related biomedical science in saving lives from cancer.
After an average treatment time of 41 days, men taking metformin showed a slowing in the growth of cancer cells in the prostate after it had been removed versus in the earlier biopsy samples, said study lead author Dr. Anthony Joshua, a staff medical oncologist with Princess Margaret Hospital/University Health Network in Toronto.
Not surprisingly, metformin also decreased blood sugar levels, insulin growth factor and body mass index (BMI, a measure of obesity).
None of the men in the study had diabetes, said Joshua, so “it remains to be seen who would benefit the most from metformin.” The most appropriate patients may be those with diabetes, those who are at risk for the disease or those whose tumors are sensitive to metformin.
It’s unclear exactly how metformin exerts its effect but it may reduce the amount of circulating insulin in the blood, and insulin can fuel the growth of prostate cancer cells, explained Joshua.
The drug may also interfere with a specific pathway linked to cancer growth, he added.
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Source: American Association for Cancer Research (AACR)