Jan. 20, 2005 -- Scientists have a new lead on colon cancer: a protein called avB6 integrin. The protein can help predict colon cancer survival and the disease's aggressiveness. It might inspire new treatments.
Colon cancer is the third most common cancer found in U.S. men and women, according to the American Cancer Society (ACS). This year, there will be almost 105,000 new colon cancer cases, more than 40,000 rectal cancer cases, and more than 56,000 colorectal cancer deaths in the U.S., predicts the ACS.
Researchers are hunting for ways to get an edge against colon cancer. From a patient's perspective, routine screening is the best bet, since early detection can make a big difference. Beginning at age 50, both men and women should start
Cancer starts in the inner lining of the colon and can grow through some or all of the other layers.
Now, scientists have more information about how colon cancer can spread.
Integrin apparently encourages cells lining the colon to become more aggressive, allowing cells to penetrate into deeper layers, new research shows.
The scientists who studied integrin included Richard Bates of Boston's Beth Israel Deaconess Medical Center and Harvard Medical School. Their findings appear in the online edition of The Journal of Clinical Investigation.
Ordinarily, cells that line the colon (and other body cavities) pretty much stay "as is." But when a wound needs healing or embryonic development is under way, the cells can change shape and function. Usually, that process goes smoothly. But if something goes wrong, healthy epithelial cells can become tumor cells.
The researchers wanted to see if integrin had anything to do with that. They measured integrin levels in 488 human colon cancer samples. Integrin turned up in 37% of the samples. Those samples happened to be the most aggressive colon cancers with the shortest survival rates.
High integrin levels cut five-year survival by 28%, compared to patients with little or no integrin. The association was most predictive in patients with early stages of the disease.
The findings suggest that the integrin could help predict patient survival. It may also become the target of new treatments for aggressive colon cancer, say the researchers.