August 2012 NUI Galway Scientists Identify Novel Role for Small RNA Molecules in Breast Cancer

The research labs of Professor Charles Spillane (Genetics and Biotechnology Lab, NUI Galway) and Professor Michael J Kerin (National Breast Cancer Research Institute, Galway) have discovered a new genetic control system implicated in breast cancer. Their research findings have been published in the latest issue of the Journal of Biological Chemistry, which is considered the 7th most important scientific journal worldwide by the Eigenfactor ranking system.

Professor Kerin highlighted that “Breast cancer is the most frequent cancer worldwide in women and while treatments and outcome are improving there is a compelling need for continued research into its cause and treatment. About 2700 new cases of breast cancer are diagnosed in Ireland each year. Advances in cancer biosciences research provide the basis for earlier diagnosis and new treatment regimes for breast cancer.”

Both research labs are collaborating to investigate a new class of genes called microRNAs which produce small RNA molecules that can switch off other genes in normal and cancer cells.  Professor Spillane indicated that “There are over 1500 different types of these small microRNA genes identified so far in human cells and it is a major scientific challenge for us to understand which ones can make the difference between a normal and a cancer cell”. Working closely with Professor Spillane and Professor Kerin, molecular biologist Dr S. Duygu Selcuklu made the discovery that a particular microRNA gene called miR-9 acts to suppress tumour growth of breast cancer cells.

In the project, the team also identified a new gene involved in breast cancer called MTHFD2 whose levels are kept down by the small RNA miR-9. However, when miR-9 levels go down in a cancer cell, levels of MTHFD2 go up and promote cancer cell development. Dr S. Duygu Selcuklu indicated that “Our findings are important as they show that high levels of miR-9 in cancer cells slows down tumour cell growth by down-regulating cancer promoting genes (oncogenes) such as MTHFD2. Measuring the levels of miR-9 and MTHFD2 in patient samples holds promise for use in the clinic as a novel biomarker in breast cancer diagnostics.”

The research was funded by the Irish Cancer Society, the Health Research Board and the National Breast Cancer Research Institute (NBCRI) in Galway.

ENDS