New gene identified in breast cancer

Researchers at the Research Institute of the McGill University Health Centre and McMaster University have identified a new player in breast cancer. This gene, beta1-integrin, has been shown to be critical in the initiation of tumour growth and development in a mouse model of cancer. Furthermore, when this gene is blocked, cancerous tumours cease to grow.

"We are the first to demonstrate the requirement for beta1-integrin in the induction of breast cancer in genetically engineered mice," says senior author Dr. William Muller, an MUHC researcher and professor of Medicine and Biochemistry at McGill University. "Our findings show that blocking the function of this gene halts tumour proliferation. We also show that in our model of breast cancer, tumour cells do not grow without beta1-integrin. These results demonstrate the importance of this gene in tumour biology. The next step is to look for therapeutics which block this gene in humans."

Dr. Muller and his colleagues from the Departments of Biochemistry and Biomedical Sciences at McMaster University, Dr. John Hassel, Natasza Kurpios and Don White, used breast-cancer-prone mice to demonstrate the role of beta1-integrin. They initially showed that removing this gene did not affect the normal mammary development of the mice. They then went on to show that if the gene was removed from already growing tumours, the tumours would cease to grow.

"This is an exciting time in breast cancer research," says McMaster University and McGill University graduate student and first author of the study, Don White. "The more players we identify, the more likely we are to cure this disease."

The findings are published in the August 23 issue of Cancer Cell and are currently available online at www.cancercell.org/.

This research was funded by the Canadian Breast Cancer Research Alliance (CBCRA) and National Cancer Institute (NCI) PO1-CA099031.