Genes May Point to Aggressive Breast Cancers
New tool might someday help doctors tailor therapies to patients
FRIDAY, April 22, 2005 (HealthDay News) -- Researchers say they're working on a promising gene-based method of identifying whether breast cancer has spread beyond the breast.
The finding is a key first step in research that could help doctors better tailor treatment to each patient's particular type of malignancy.
Previous studies have investigated patterns of genes that are active in primary tumors, but not active in breast cancers that have spread beyond the primary site. However, individual patient genetic differences have often made it difficult to interpret those results.
This new technique analyzes variations in gene activity between different cancer cell lines. Even though they come from the same human breast cancer, these lines often have different capabilities when it comes to spreading to other areas of the body, the researchers said.
In this study with mice, researchers used a gene chip of 22,000 genes to determine which genes were switched "on" and "off" in metastatic (spreading) versus primary tumors.
Researcher Dr. David Tarin, of the University of California, San Diego, said that "further work using this strategy will identify collections of marker genes (signatures) that predict the future behavior of a given human cancer from samples taken from the patient. The purpose is to find signatures of malignancy that indicate whether a cancer is more or less aggressive. The aim is to minimize over-treatment of those who do not need it and avoid under-treatment of those patients who do."
This study identified several candidate genes that may help researchers better understand cancer metastasis. However, the findings can't be directly extrapolated to human tumors, the study authors said. Even so, this study provides an important first step for future research that may lead to improved cancer diagnosis and treatment, they said.
The study appears in the May issue of the American Journal of Pathology.
The American Cancer Society has more about breast cancer.