Moreover, like other cytokines, new engineering approaches are currently tested in cancer immunotherapy, including IL-7 combination with the Fc domain of different antibodies (e.g., anti-PDL1) (WO2019144945A1), antibody fragments (Pasche et al., 2011) or other cytokines (e.g., GM-CSF, IL-15) (Fig. 1) (Hsieh et al., 2015; Song et al., 2016). This evidence concerns the gene IL15 and cancer.