Print this page 
Trial tests diabetes drug on breast tissue
Posted 20 September 2010
In a new clinical trial researchers at Prince Henry's Institute (PHI) in Melbourne are testing the effect of a commonly used diabetes drug on breast tissue. The findings will be important in addressing how much potential the drug Metformin has for treating or even preventing breast cancer.
Dr Kristy Brown, Terry Fox Foundation Fellow, at PHI will present the latest research findings on 25 September at an international scientific meeting to be held in Edinburgh, Scotland.
"This research may lead to safer and cheaper breast cancer therapies and even a prevention approach which would involve women at risk taking a simple daily medication" says Dr Brown.
One in nine women is affected by breast cancer during their lives.
The new clinical study builds upon the discovery last year by PHI researchers of a new and "critical link" between obesity, the hormone oestrogen and breast cancer. The team is now exploring several drug candidates that would shut down hormone production specifically in breast tissue.
One drug showing particular promise in reducing breast cancer risk is Metformin, which is already commonly used to treat Type 2 diabetes. The patent on the drug was lifted in 2000. There is now major interest amongst researchers and clinicians in the potential of this common and cheap drug to treat or prevent some cancers.
In July 2010 the SEMB trial (Study on the Effects of Metformin on Breast tissue) commenced, a collaboration with researchers from Monash University. The randomised study will involve up to 60 Victorian women. Participants in the study will already have elected to undergo breast reduction and they will take the Metformin medication each day for a month prior to surgery.
Now that recruitment for the study has commenced the PHI researchers expect to soon begin their analysis of the breast tissue exposed to Metformin. The team will examine in detail how Metformin affects the links with hormones in the breast.
There are several retrospective studies which have found an apparent reduced breast cancer risk in women with diabetes who take Metformin as opposed to women who received other treatments for diabetes.
"The existing evidence by itself would not yet support widespread use of Metformin to treat or prevent breast cancer however our studies are helping answer this key question" says Professor Evan Simpson who leads the research group at PHI. The group receives major support from the Victorian Breast Cancer Research Consortium, a Victorian Government funded "institute without walls".
The real test and evidence for using Metformin in breast cancer prevention or treatment will come through well designed large-scale randomised controlled clinical trials, often described as the gold standard in testing a drug. The researchers at PHI are already busy planning and collaborating towards what they hope will be a major step forward in breast cancer prevention and treatment.
About Prince Henry's Institute
PHI is an independent not-for-profit medical research institute based at Monash Medical Centre in Victoria, Australia. The Institute has over 160 staff and students and our vision is to improve quality of life through the investigation of hormones in the fields of reproductive health, cancer, diabetes, obesity, bone health and cardiovascular disease. Research at PHI includes fundamental laboratory research understanding human biology, translational studies focussed upon developing better diagnostics and new treatments and clinical programs to improve patient care.