Cancer Requires Support From Immune System To Develop

Who would have ever thought that cancer would require the aid of cells in the immune system to grow? At UT-Southwestern Medical School, a research team led by Dr. Luis Parada, are investigating cases of exactly that. Instead of injecting laboratory mice with drugs that attack the tumor, they are concentrating the drug therapy on immune cells surrounding the tumor. The results were a reduction in size and a slowing of the metabolism of the tumor. The research was focused around tumors known as plexiform neurofibromas, which are typically located around peripheral nerves. Due to their location and complexity, these tumors are extremely difficult to remove, and therefore are typically non-curable.

The initial alterations of the mice’s genetic structure provided a lot of information essential to this discovery. They noticed that in order for the tumors to develop in the mice, the Schwann cells had to have two mutated copies of the Nf1 gene, and the other cells had to have at least one copy of the mutated Nf1 gene. In addition, it was noted that before the tumors would even form, mast cells would migrate to the area. This migration indicated the importance of the mast cells, part of the immune system, in the tumor’s formation. The mast cells contain “c-kit”, a molecule on the cell’s membrane that primarily controls cell migration and proliferation. In their experiments, they treated these genetically engineered mice with Gleevac, a drug used in the treatment of other cancers, for its ability to inhbit this “c-kit” molecule. Using PET scans, the results showed that metabolism of the tumor cells had been cut by half, and the size of the tumors had decreased in comparison to the control group of mice.

I found this article extremely interesting, as it deals with both genetics and investigations/treatments of cancers. It also incorporates the nervous system and immune system, both of which we have been talking about recently. Such success in these lab mice is paving the way for clinical trials towards potential human treatment. They were also able to test the effects of Gleevac on a girl suffering from neurofibramitosis-1, and found that the tumor shrank by 70%, left no side effects, and remained dormant for six months after the treatment. With this knowledge, researchers may be able to take a new approach in finding suitable treatments for previously untreatable cancer ailments and tumors.

http://www.sciencedaily.com/releases/2008/10/081030123945.htm

Shawn Schepel
VTPP 434-502