Gene Targeted for Therapy in Fighting Colon Cancer

Researchers may have targeted a gene for therapy to fight colon cancer, according to two reports published in the journal Nature Cell Biology.

The gene, called APC (adenomatous polyposis coli), normally acts as a tumor suppressor and mutations in the gene can be inherited or occur randomly, said researchers at Leiden University in the Netherlands.

The gene mutations may lead to instability of the chromosome, causing some cells to have too many chromosomes and others not to have enough, said the researchers. An abnormal chromosome number, which usually occurs during cell division, is a common factor in cancer cells.

Colorectal tumors with chromosome instability have a poor prognosis, said Dr. Riccardo Fodde of Leiden University and co-author of one of the studies. The cause of the instability has been unknown.

Researchers studied mouse embryos, finding that APC normally plays a role in regulating chromosome stability by ensuring that the appropriate number of chromosomes are in each newly divided cell. Stem cells with defective APC genes displayed extensive chromosome instability in the studies.

A second study detected a link between mutations in APC and chromosome instability in embryonic stem cells that had a shortened version of the APC gene. These studies show the first molecular link between chromosome instability and the APC protein that is commonly mutated in colon cancer, especially in the early stages.

Reversing changes induced by the loss of normal APC early by targeting the most vital mechanism would prevent malignant colon cancer in patients, an approach that would be especially helpful in patients with hereditary colon cancer caused by mutations in APC, according to the researchers.

Other sources: Nature Cell Biology, Reuters