Lombardi Cancer Center researchers pinpoint abnormalities on cancer-fighting gene

WASHINGTON, D.C. – Researchers at Lombardi Cancer Center at Georgetown University Medical Center have identified several key mutations on the cancer-fighting gene known as p53—allowing them to study this gene more closely than was previously possible and giving new insights into how cancer treatment may be customized down the road. These developments will be presented at the 92nd annual meeting of the American Association for Cancer Research, to be held March 24-28 in New Orleans.

The Lombardi team has encoded a biochip, or microarray, with a complete, normal p53 gene —known as the “guardian of the genome” because it stops the abnormal cell growth that leads to cancer. Scientists then amplified a copy of a flawed p53 gene extracted from a cancer patient, and overlaid it onto the model of the normal p53 gene. A laser then screened the entire chip for abnormalities to identify precisely where on the gene they occur. So far, the researchers have found five specific “hotspot” sites on the p53 gene where mutations are more likely to occur.

“While we still have a long way to go toward finding out the cause for cancer, our research is an important step in that journey,” said Shiva Krishnan, research associate. “Before you can fix something, you have to know what went wrong in the first place. Now that we have identified these specific abnormalities on the p53 gene, we are in a better position to find ways of fixing it.”

The Lombardi researchers are studying approximately 500 women in Buffalo, N.Y., who were diagnosed with breast cancer between 1985 and 1995, and a smaller control group who have never had breast cancer.

The research is being funded by a Department of Defense breast cancer grant.

Georgetown University Medical Center includes a biomedical research enterprise, and the nationally ranked School of Medicine and School of Nursing and Health Studies. Lombardi Cancer Center, an integral component of Georgetown University Medical Center, is one of only 38 Comprehensive Cancer Centers in the United States—and the only one in the Washington, D.C. area—designated by the National Cancer Institute.