The immune system is constantly on the alert for cells that have sustained DNA damage. When a cell divides its DNA molecules are, to varying degrees, usually damaged. Yet researchers have not been able to determine how these damaged cells are able to “slip under the radar” and are not caught by the vigilant immune system.

Then in the course of conducting their research, Dr. Gupta and his team at the UNC Lineberger Cancer Centre discovered why and how the cGAS/STING pathway is unlocked.

The new findings were published in MedicalXpress, and recently appeared in the journal Nature.

While conducting their research, the team discovered the elusive enzyme called cyclic GMP-AMP synthase (cGAS) that releases the cGAS/STRING (stimulator of interferon genes) pathway. The pathway, which functions as a messenger for the immune system, is usually turned off in order to prevent a buildup of cancer formation in healthy organs.

About Inflammation

Inflammation is the immune system’s response when it is threatened by harmful pathogens or damaged cells. The pathway is released, the damage is detected, and the harmful stimuli is removed.

Dr. Gupta and associates suspect that the absence of this pathway may be the reason that breast cancer cells can withstand such high levels of DNA damage and not be recognized by the immune system.

Herpes simplex, chickenpox, and other double-stranded DNA viruses, as well as DNA-damaged cells, are considered threats to the body. When the damaged cells are identified, the immune system locates the threat and eliminates it.

In 2020, research teams from UNCs Department of Biophysics and Biochemistry were one of the first teams to announce discovery of cGAS. In this instance their paper was published in Science and explains how cGAS is captured.

Their paper described cGAS as being able to prevent the body from releasing an inflammatory immune response unless it was an absolute necessity.