This section focuses on current breakthroughs in the biology of the abovementioned cytokines (IL-2, IL-15, IL-7, IL-21, IL-10, IL-12, IL-18, IFNs and TNF-α), as well as engineering approaches and competitive landscapes aimed at resurrecting cytokine immunotherapy and promoting their clinical translation for the treatment of cancer. This evidence concerns the gene IL15 and cancer.