Disclosed are means, methods, and compositions of matter useful for generation of cancer inhibitory effector cells producing interleukin-17 (IL-17). In one embodiment a cellular population is obtained, said cellular population is exposed to agents capable of inhibiting NR2F6, whereby said inhibition of NR2F6 results in upregulation of IL-17 production, said upregulation of IL-17 production associated with acquisition of anti-tumor activity.