It makes sense that tapping into the body's immune system would lend itself to good therapies. 

See also:

Steve Cara in an examination room at Memorial Sloan Kettering Cancer Center. Mr. Cara learned two years ago that he had advanced lung cancer, but immunotherapy drugs called checkpoint inhibitors have helped wipe out the disease.

http://mobile.nytimes.com/2016/07/31/health/harnessing-the-immune-system-to-fight-cancer.html