Now a virus or bacteria sets up alarms in the immune system, which enables it to fight many diseases. Unfortunately, the immune system will overlook a cancer cell, perceiving it to be nothing more than a regular cell. So a cancer cell is like that obnoxious jerk that crashes your party, gets you drunk, starts a fight, and before leaving destroys your toilet in the most sickening ways imaginable. But that's okay ladies and gentlemen, because IRT is the bouncer. It enables the immune system to recognize cancer cells as unwanted party guests and the ability to destroy the cancer.