COX2, HB-EGF and ST6GALNAC5 are the three genes that have been discovered to help direct breast cancer to spread to the brain. The first two are genes that help move the cancer cell and make it more evasive and the third gene provides the cancer cells a way to exit the blood circulation through bursting capillaries. The cancer cells seem to make it to the brain after the initial tumour has been removed. This shows that they lack the capability to enter the brain yet, due to network of capillaries that form a blood-brain barrier.
The project is led by investigators at Memorial Sloan-Kettering Cancer Center (MSKCC). The genes were discovered by comparing the genomes of cancer cells that had invaded patient’s brains with those that haven’t. ST6GALNAC5 is an enzyme that coats the breast cancer cells with a coating that allows it’s infiltration to the brain. It also seems that the COX2 and HB-EGF genes, which prepare the cell for entrance into the brain, are also present in cancer cells that have infiltrated the lungs.
Other research has also shown that there are three genes involved in breast cancer cells metastasising, or moving from their original tumour site. Experiments by Joan Massagué and his colleagues at the Memorial Sloan-Kettering Cancer Center in New York City have shown this by injecting human breast cancer cells into arteries of mice. Of those who developed brain cancer, these three genes were expressed.
This new discovery presents possibly remedies as drugs can be developed to attach the coating on cancer cells, which is just now being discovered as to being the cause of cancer cells invasion to other parts of the body.
Resources:
http://www.newscientist.com/article/mg20227074.700-cancers-oneway-ticket-to-the-brain.html
http://www.sciencedaily.com/releases/2009/05/090506144305.htm
