"There are an increasing number of outbreaks of cancer, especially blood cancer, in which the hyperactivity of Tyk2 is the cause“, explained Mathias Müller of the Institute of Animal Breeding and Genetics at the University of Veterinary Medicine in Vienna. The signal conveyors can also trigger excessive immune reactions.
For this reason, substances are being developed which inhibit the previously known function of Tyk2 (or "kinase"). Signals are transmitted by attaching a “flag” (phosphate residue) to other proteins. Such medicines would be helpful in the fight against cancer and inflammation-related illnesses, the researchers say.
However, complications could arise in light of the fact that Tyk2 makes a considerable contribution to the maturing and activation of “natural killer cells”.
In fact, mice in which completely lacked Tyk2 had killer cells which were baldy prepared, and could no longer control cancer growth. However, in animals in which Tyk2 was present but its kinase activity was inactivated, cancer growth was strongly suppressed and the natural killer cells retained their ability to effectively kill the cancer cells.
"Medicines aiming to inhibit kinase activity do not damage the work of the immune system“, explained Birgit Strobl of the Department for Molecular Genetics at the University of Veterinary Medicine in Vienna. Instead, they are more promising for cancer therapy than was originally thought.