From Science Daily: Researchers at the University Of South Florida Health Sciences Center have unlocked at least part of the mystery of how tumors flourish undetected by keeping their presence a secret from sentries of the body’s immune system. “Flying beneath the radar” is how Nature Reviews Cancer labels the mechanism of tumors evading capture.
The tumor’s activation of Stat3 (from the STAT family of proteins that regulates genes) secretes factors that inhibit the body’s immune responses by keeping dendritic cells from maturing. The activation also blocks expression of inflammatory mediators required to trigger the immune system. This discovery shows that cancer is allowed to wreak havoc on the body’s immune system because it knows how to fool the body’s defensive arsenal. It opens the way for new treatments to help flush the cancer cells into the open, so the body’s armies against disease can destroy them.