Many drivers feel the urge to floor the accelerator on a crisp sunny day when the highway ahead seems to stretch straight to eternity. But only the most foolish would cut the brake line while pushing the pedal to the metal.
Yet one of the body's most potent cancer-causing genes does precisely that inside a cell, scientists at the University of Rochester Medical Center have found. The result of the unfettered molecular joy ride is, oftentimes, cancer. Details of the research are in the October issue of the Journal of the European Molecular Biology Organization (EMBO).
Scientists have long recognized that the protein produced by a gene known as myc spurs a cell to grow. Just like pushing the accelerator makes a car move forward, producing more myc makes a cell grow and divide. Too much myc spells an invitation to cancer, where cells grow uncontrollably and invade other tissues.
Now scientists have found that myc is even more powerful than they anticipated: The gene also has a role in disabling the molecular signals, the "brakes," that cells rely on to slow growth. When myc is out of control, not only is the accelerator floored but the brakes are out. It's no wonder that the gene plays a role in many human cancers, including those in the lung, colon, breast, bladder, and brain.
"Myc is central to our cells' ability to grow, divide, and even die when they should," says Hartmut Land, Ph.D., director of the University's Center for Cancer Biology and lead investigator of the EMBO study. "Basically, myc is like the starter of an engine; it's responsible for making the whole cell go. It's a very potent gene, but one that's been slow to yield its secrets. Myc has been a conundrum."
Land's team showed that myc controls another protein, cyclin D, known to
play a big role in making cells grow; the EMBO paper marks the first time
scientists have identified the "brains" behind cyclin D's actions. Land's team
also found that
Contact: Tom Rickey
University of Rochester