NEW YORK (Reuters Health) - Treatment with gefitinib, an orally active epidermal growth factor receptor (EGRF) inhibitor, may help prevent human breast cancer, findings from an animal study suggest.
In the new study, treatment with the drug delayed tumor onset by more than 80 days in mice engineered to develop ER-negative breast cancer. Such a therapy could fill an important gap as current chemopreventive agents are only directed against ER-positive tumors, the report indicates.
Currently, gefitinib, which is marketed by AstraZeneca as Iressa, is approved by the FDA for the treatment for non-small-cell lung cancers after the failure of both platinum-based and docetaxel chemotherapies.
Dr. Powel H. Brown, from Baylor College of Medicine in Houston, and colleagues assessed the ability of gefitinib to block signal transduction in normal and malignant breast cells. In addition, the drug’s effects were evaluated in a murine model of ER-negative breast cancer.
The researchers’ findings are reported in the December 17th issue of the Journal of the National Cancer Institute.
The authors found that gefitinib did suppress signal transduction in both normal and malignant breast cells. Moreover, in control mice the median time to tumor onset was 230 days, whereas in gefitinib-treated mice, it took at least 310 days for tumors to occur (p < 0.001).
“That amount of delay could potentially be clinically meaningful in humans,” Dr. Brown told Reuters Health. “Also, at the end of the study when all of the control mice had developed cancer, only about 25% in the gefitinib group had cancer.”
“In the current study, we were looking at gefitinib as way to prevent breast cancer,” Dr. Brown noted. Although clinical trials have studied the drug as a treatment for breast cancer, “so far, no primary prevention trials have been conducted. Before bringing it to clinical use we need to better understand its toxicity profile,” he emphasized.
In a related editorial, Dr. Dennis J. Slamon, from the University of California at Los Angeles, and colleagues echo this concern, noting that there is no long-term data on gefitinib’s safety. Most of the side effects seen with the drug are mild, but interstitial lung disease, a potentially life threatening effect, has been reported in up to 2% of patients.
Source: J Natl Cancer Inst 2003;95:1813-1815,1825-1833. [ Google search on this article ]
MeSH Headings:Breast Neoplasms: Membrane Proteins: Neoplasms: Neoplasms by Site: Receptors, Cell Surface: Receptor, Epidermal Growth Factor: Receptors, Gastrointestinal Hormone: Receptors, Growth Factor: Receptors, Peptide: DiseasesCopyright © 2002 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.
