Diabetes drug could reduce risk of breast cancer

A new study has provided further evidence that the type 2 diabetes drug metformin could help to reduce the risk of breast cancer in older women.
Researchers found that the commonly prescribed drug, which works to raise insulin sensitivity and improve the control of blood sugar levels, could reduce the chances of post-menopausal diabetic women developing invasive breast cancer.
The study, which was reported in the Journal of Clinical Oncology, examined the link between diabetes, metformin and breast cancer for more than 68,000 women aged between 50 and 79, showing that the incidence of invasive breast cancer was 25 per cent less for diabetic women who took metformin than for those who didn’t take the drug.
Rowan Chlebowski from the Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, who co-authored the study, said that metformin “may inhibit the master regulator of the cell, mTOR, changing critical pathways involved in cancer.” This pathway can be affected by a variety of cellular signals, such as hormones including insulin.
However, the scientists involved admit that there is still insufficient evidence to alter clinical practice and see metformin as a cancer prevention drug, as they hadn’t proved a causal relationship, despite other studies finding that metformin may also be able to reduce the risk of cancers of the pancreas, liver and prostate.