In the context of cancer, while it is conceivable that various group 1 ILC subsets play an anti-cancer effector function due to their IFNγ production, caution is needed since the modulation of the immune cell response might occur in the tumor microenvironment, thus changing the role of these cells from anti- to pro-tumor phenotype as reported for other immune cell types (55, 56). The gene discussed is CCL27; the disease is cancer.