Genetic analyses with microchips will improve diagnosis and prognosis in breast cancer, explained Dr. Jeffrey Green at the Center for Applied Medical Research (CIMA) of the University of Navarra. The director of the area of Transgenic Laboratory Techniques for Cellular Regulation and Carcinogenesis of the National Institutes of Health (NIH) of the U.S.A took part in a seminar in the area of Oncology of the CIMA. He spoke about his research, based on the development of genetically modified mice, in order to study breast tumors.

The expert noted that "genetic analyses are beginning to be used in very sophisticated techniques, such as biochips, which can study the profile of each patient. This has permitted us to understand that breast cancer has many varieties, despite the fact that the various types of tumors may look alike under the microscope. Thanks to these techniques, we can classify patients into subgroups. The additional use of bioinformatics makes it possible to handle all this vast amount of information in order to discover new ways by which altered genes can produce these specific types of cancer."

In his opinion, better classifications of patients according to the genetic profile of their tumors will provide improvements in their diagnosis, prognosis, and therefore in the application of more specific therapies.

A long process prior to application in patients

Dr. Jeffrey Green outlined the steps of the research: "First, we must identify key altered genes for this type of cancer, which will constitute new therapeutic targets. Afterwards, we must design drugs in order to correct the function of the altered gene in the tumor. One must perform biochemical studies with these potential drugs, and later test them in animals, measuring their toxicity, and finally evaluating their anti-tumor activity in patients."

The researcher from the NIH recognizes, on the one hand, the necessity to employ animal models in the fight against cancer in humans, and, on the other hand, notes the limits which are caused by testing in animals which are different from humans: "We will be able to find out in which concrete aspects they are similar and in which they are different. When we know which genes are altered in a similar fashion, we will be able to test more effectively the new drugs designed to work against these genes. Up to now, the most-used technique has been that of cells cultivated in vitro, but it has already been proven that this is not sufficient for predicting the response in patients."