Starving Out Colon Cancer
Reported April 29, 2010
(Ivanhoe Newswire) New research shows that many of the colon cancer cells that form tumors can be killed by inhibiting the cells’ ability to absorb a key nutrient.
Normal adult stem cells are able to renew themselves by dividing almost without limit. Cancer stem cells, or CSCs, are believed to be the result of mutations of normal stem cells. When CSCs divide, they can develop into new CSCs or into any type of cancer cell. CSCs play an important role in the recurrence of tumors following chemotherapy.
Traditional chemotherapy is good at killing most tumor cells, but is not as effective with CSCs. This means that even when tumors shrink or disappear with chemotherapy, the CSCs survive, replicating themselves and eventually producing new tumor cells.
CSCs have properties similar to normal stem cells, so researchers had to find a way to attack them while keeping the adult stem cells alive. To do that, the research team inactivated the insulin-like growth factor receptor (IGF-1R), which is a receptor found in increased amounts in colon cancer cells. They found that colon cancer CSCs needed more IGF to live than other cells, and could not function without the IGF receptor. By lowering or inhibiting the IGF receptor, a new treatment strategy for colon cancer could be developed.
Further research is necessary to determine whether reducing the number of CSCs can actually reduce the recurrence rate of colon cancer.
Colorectal cancer remains the third deadliest cancer in the U.S. According to the American Cancer Society, there are 147,000 new cases of colorectal cancer each year, and 49,920 deaths. About half of all cancers, including colon cancer, reoccur within five years of treatment.
Source: Federation of American Societies for Experimental Biology, April 28, 2010