Macrophages are a type of white blood cell that are among the body's first line of defense against infection. In addition to killing harmful microorganisms, macrophages typically can initiate a response against tumors. However, macrophages, like other cells, can enter a state called senescence, which is linked to aging, disease and multiple physiological problems.
When cells become senescent, they stop dividing, but they do not die and are not always eliminated from the body. They can linger and accumulate in tissues and may secrete molecules that are harmful. This is why senescent cells have been called "zombie cells." The reason why healthy cells become senescent is not well understood.
In a new Cancer Cell study, researchers discovered senescent macrophages in the lung that not only lingered but also promoted tumor growth.
"Conceptually, the idea that a macrophage can become senescent and be tumor-promoting is unexpected," says Darren Baker, Ph.D., a Mayo Clinic senescent cell biologist and senior author of the study. "This finding brings us one step closer to better understanding how tumors and cancer form at the cellular level."
Read the rest of the article on the Discovery's Edge blog.
Other Mayo Clinic medical research websites: