FRIDAY, Nov. 3, 2006 (HealthDay News) -- Multiple copies of a gene called uPAR are associated with the spread of early-stage breast cancer, U.S. researchers report.
The gene offers a promising target for drugs to slow or halt the progression of the disease, says a team from the University of Texas Southwestern Medical Center at Dallas. It could also serve as a screening tool for determining which kinds of drugs a breast cancer patient will respond to, the researchers said.
The study was published in this week's issue of the Proceedings of the National Academy of Sciences.
The researchers analyzed individual tumor cells from 72 patients with advanced breast cancer. They found that about 20 percent to 25 percent of breast cancer patients carry too many copies of the uPAR gene, which starts a process that allows cancer cells to escape into the bloodstream and to adjacent tissues.
"The uPAR system probably plays a role in metastases in many of the common solid tumors," study senior author Dr. Jonathan Uhr, a professor in the Cancer Immunobiology Center, said in a prepared statement.
He and his colleagues also found that uPAR may amplify the effects of the breast cancer-causing gene HER-2.
"This gene, uPAR, is an important oncogene, and that is why we determined whether or not it is amplified. Unexpectedly, it is usually amplified in the same tumor cell with HER-2 gene amplification. This has significant implications for treatment with targeting agents," Uhr said. "Moreover, we stress the value of individual tumor cell analysis for providing information that cannot be obtained by conventional pathological examination."
The U.S. National Cancer Institute has more about breast cancer.