Researchers from the Indiana University School of Medicine and colleagues at the University of Texas Southwestern and Case Western University have determined how the protein Mdm2, which is elevated in late-stage cancers, disables genes that suppress the growth of tumors. The finding may lead to the development of new drugs for late stage breast cancer and other difficult to treat malignancies.
The investigators have identified a critical pathway that stimulates the production of Mdm2 causing an increase in the level of protein that bind to p53, the most common tumor suppressor, as well as other tumor suppressors, and extinguishes tumor suppression activity. The study appears in the January 2010 issue of the Journal of Clinical Investigation.
Principal investigator Lindsey Mayo, Ph.D., assistant professor of pediatrics at the Herman B Wells Center for Pediatric Research at the IU School of Medicine and an Indiana University Melvin and Bren Simon Cancer Center member, says that keeping Mdm2 inactive and preventing the destruction of the tumor suppressor that Mdm2 targets, is critical to preventing cancer from spreading within the body.
To explain the role of Mdm2 and how the newly identified pathways function, Dr. Mayo uses the analogy of a florescent ceiling fixture in which Mdm2 is the fluorescent bulb. "Initially, it was only known that the light was on, not how it was turned on. We discovered the wall switch and wires that connect to the light fixture to turn on the fluorescent light."