( s says co-author Dr. François Robert ...)Scientists discover genetic pathway responsible for breast cancer cell growth

Of particular importance was the discovery of a gene called FOXA1, known as a transcription factor. "FOXA1 can be viewed as a facilitator of estrogen action on cancer cells," says Josée Laganière, a graduate student at the MUHC and principal author of the paper. "It is found in breast cancer tumours that express the estrogen receptor." In their study, the researchers found that the FOXA1 gene was required for the estrogen receptor to activate the growth of breast cancer cells.

"By inactivating the FOXA1 gene in laboratory cell cultures, we were able to block the growth-inducing effect of estogen, and thus halt the growth of breast cancer cells," says Dr. Giguère. In FOXA1 researchers have found a new target that affects the development of breast cancer. In practical terms, efforts can now be focused on developing a more precise cure/treatment for cancer based on this gene. "The problem with cancer drugs in general has been that they are often untargeted, which is why patients experience side effects," notes Dr. Giguère. "The more focused the drugs the less side effects and the more chance you have to cure the disease."

"Research targeting individual molecules associated with pathogenesis of cancer has led to positive clinical results," says Dr. Joseph Ragaz, Director of MUHC Oncology Program. "Evidence-based data on agents such as Gleevac in leukemia, Avastin in colorectal cancer, and more recently with Herceptin for breast cancer, confirm that the efforts of researchers like Dr. Giguere and his team save lives and money. These connections between research and health care are one of the strengths of academic hospitals like the MUHC."