Chuck it out

摘要

Take a peek at the stuff pushed towards the back of your refrigerator shelves. Go ahead, look. Not a pretty sight, is it? Green fur on the lemon yogurt. Slightly slimy salad. A certain, ahem, "bouquet" about the fish left from last Monday's dinner. Time to clean up before things get out of hand. Your body's cells face a similar chore. Just as you need to toss out leftovers when they turn bad, your cells have to get rid of proteins that have begun to do more harm than good. When cells need to stop dividing, for example, they must destroy the proteins that trigger growth. If they fail to do this, the unchecked cell division becomes cancer.