Cytokines, JAK-STAT Signaling and Radiation-Induced DNA Repair in Solid Tumors: Novel Opportunities for Radiation Therapy

A number of solid tumors are treated with radiation therapy (RT) as a curative modality. At the same time, for certain types of cancers the applicable doses of RT are not high enough to result in a successful eradication of cancer cells. This is often caused by limited pharmacological tools and strategies to selectively sensitize tumors to RT while simultaneously sparing normal tissues from RT. We present an outline of a novel strategy for RT sensitization of solid tumors utilizing Jak inhibitors. Here, recently published pre-clinical data are reviewed which demonstrate the promising role of Jak inhibition in sensitization of tumors to RT. A wide number of currently approved Jak inhibitors for non-malignant conditions are summarized including Jak inhibitors currently in clinical development. Finally, intersection between Jak/Stat and the levels of serum cytokines are presented and discussed as they relate to susceptibility to RT.