Agressive Cancers Co-Opt Fat Cells To Do Their Dirty Work
Though they are not exactly hit men, certain enzymes in fat cells have been found aiding and abetting the spread of the most aggressive cancer cells. The guilty enzymes are the monoacylglycerol lipase (MAGL) enzymes, which put cancer cells into overdrive when they come in contact.
In the January 8, 2010 issue of Cell, researchers from Scripps Research Department of Chemical Physiology and Harvard Medical School, report how they discovered the fatty offenders. In attempting to learn why some cancers are more aggressive than others, they compared changes in the non-aggressive cancer cells to those in the aggressive cancer cells.
As if they were profiling a crime, Benjamin Cravatt, Chair of the Scripps program, and postdoctoral candidate, Daniel Nomura, used a Scripps-pioneered "activity-based protein profiling," which allows researchers to tag and see all of certain members of a family of enzymes at once. Once tagged, the pair sought to watch the activity of cells in the serine hydrolases family, which had been implicated in cancer and other diseases.
What they found was that MAGL, a lipase enzyme that breaks down stored fats, or lipids, was the culprit actually capable of converting less aggressive cancer cells into more aggressive cancer cells, by producing fatty acids. Fatty acids communicate with other cells and encourage more cell growth, in this case more cancer growth.
This finding may be a link between obesity and cancer, because people who eat high fat foods are actually feeding themselves free fatty acids. When cancer cells make contact with free fatty acids, they co-opt their communication system to create more cancer cells.
Sounds just like a science fiction thriller. It's just possible that the hero may be a new medication that inhibits MAGL's activity. One bright spot is that MAGL is not needed for cell survival!