Researchers from the University of Michigan Comprehensive Cancer Center have identified a gene that is overexpressed in 90 percent of pancreatic cancers, the most deadly type of cancer.
Expression of the gene, Ataxia Telangiectasia Group D Complementing gene, called ATDC, is on average 20 times higher in pancreatic cancer cells than in cells from a normal pancreas. What's more, the gene appears to make pancreatic cancer cells resistant to current therapies.
"One of the challenges in pancreatic cancer is that it is biologically aggressive and it does not respond well to chemotherapy or radiation. We found that ATDC not only causes the cancer cells to grow faster and be more aggressive, but it also makes the cancer cells particularly resistant to chemotherapy and radiation. By targeting this gene, we may be able to make cancer cells more sensitive to the therapies we already have in hand," says senior study author Diane Simeone, M.D., director of the Multidisciplinary Pancreatic Cancer Clinic at the U-M Comprehensive Cancer Center.
Results of the study appear in the March issue of Cancer Cell.
The researchers injected into mice tumor cells expressing ATDC and compared that to a separate group of mice injected with tumor cells in which ATDC was suppressed. In the ATDC-expressing group, tumors grew in all the samples and were significantly larger and starting to metastasize, or spread. In the group in which ATDC was not expressed, only minimal signs of tumor growth were seen after 60 days.
"This particular gene promotes the biologic aggressiveness of the cancer," says Simeone, who is also Lazar J. Greenfield Professor of Surgery and Molecular & Integrative Physiology at the U-M Medical School.
In addition, the researchers found that ATDC is most highly expressed at the point when pre-cancerous cells become malignant. ATDC was also linked to increased levels of a signaling protein called beta-catenin, which is known to play a key role in cancer development.