| VOL. 23, NO. 9||NOVEMBER 14, 1997 |
Genetic Mutations Can Increase Breast Cancer
utations in the gene P-TEN can increase a woman's risk of breast cancer, according to scientists at Columbia's College of Physicians & Surgeons.
The findings identify the third breast cancer susceptibility gene; the other two such genes are BRCA1 and BRCA2.
The discovery could lead to better tests for early detection and more effective treatments. The study, published in the Nov. 1 issue of the American Journal of Human Genetics, was a collaboration between Columbia scientist Monica Peacocke and Myriad Genetics in Salt Lake City, Utah.
The P-TEN gene, also called MMAC1, is located on chromosome 10. The role of this chromosome in the development of various sporadic cancers has been investigated for nearly a decade. Peacocke and colleagues made their discovery while searching for the genetic basis of Cowden's syndrome, a little-known dermatological disorder.
The autosomal dominant syndrome, which affects mainly women, causes skin rashes, tiny wart-like bumps, thyroid disease, andbeginning in the teen-age yearssevere benign fibrocystic disease. By their 40s, 50 to 75 percent of women with Cowden's syndrome develop breast cancer.
"Cowden's syndrome is an under-recognized and under-diagnosed disorder. The identification of this gene will allow us to develop screening tests so that these women can follow early detection and prevention strategies and get prompt treatment of breast cancer," says Peacocke, associate professor of medicine and dermatology at Columbia-Presbyterian Medical Center.
Cowden's syndrome may also increase a woman's risk of endometrial cancer. Therefore, women with the genetic mutation who also have breast cancer might not be candidates for treatment with tamoxifen, which itself can increase the risk of endometrial cancer.
Researchers are not sure of the exact incidence of Cowden's syndrome. Most cases of breast cancer are the result of sporadic, as opposed to inherited, mutations.
The study's other authors were Hui C. Tsou, David H.-F. Teng, Xiao Li Ping, Valeria Brancolini, Thaylon Davis, Rong Hu, Xiao Xun Xie, Alexandra C. Gruener, Carolina A. Schrager, Angela M. Christiano, Charis Eng, Peter Steck, Jurg Ott and Sean V. Tavtigian.
The study was funded by the National Cancer Institute and the National Institute on Aging.
Written by the Office of External Relations, Health Sciences Division.