Cancer cells send out 'drones' to battle immune system from afar

Checkpoint inhibitor therapies have made metastatic melanoma and other cancers a survivable condition for 20 to 30 percent of treated patients, but clinicians have had very limited ways of knowing which patients will respond. Researchers have uncovered a novel mechanism by which tumors suppress the immune system. Their findings also usher in the possibility that a straightforward blood test could predict and monitor cancer patients' response to immunotherapy.