Researchers have identified a genetic signature that can predict an improved clinical outcome in patients with breast cancer, and which could help in the development of new targeted therapies, they reported at the IMPAKT Breast Cancer Conference in Brussels.

An international research team led by Dr Sherene Loi from the Jules Bordet Institute in Brussels studied a molecular pathway, known as the PI3K pathway, which is deregulated in several cancer types using genomic profiling.

By analysing the expression of different genes induced by a specific mutation in a molecule called PIK3CA, a critical part of the pathway commonly deregulated in breast cancer, they found that these genes were correlated with an improved clinical outcome in over 1500 women with the disease.

Cancer researchers have become particularly interested in the PIK3CA gene in recent times. Drug companies are currently developing targeted drugs aimed at inhibiting specific forms of the protein PIK3CA codes for, called P110-alpha. The new findings could have important implications for designing those drugs, the researchers say.

"This is a hot area of research. This pathway is important for the development of new targeted therapies in breast cancer," said Professor Jose Baselga, co-chair of the IMPAKT Breast Cancer Conference, who was not involved in the research. "Dissecting the molecular pathway and its biological mechanisms is an important step in that process."

Professor Baselga said doctors could eventually test for specific mutations in the PI3K pathway before treating their cancer. "Similarly to the way we currently test for HER2 expression levels, we may need to check for these other mutations up front because they will provide specific opportunities for targeted treatments."

The IMPAKT conference is designed to present and discuss advances in translational research and ways to quickly transform laboratory discoveries into tools that clinicians can use to help make decisions about the way they treat patients in their daily practice.