Consistent with its function as the major STAT protein downstream of IL-7, IL-2, and IL-15, Gotthardt et al. reported STAT5 role in tumour angiogenesis showing that Stat5Δ/ΔNcr1-iCreTg-Vav-Bcl2 mice displayed an increased tumour growth compared with wild-type mice [51]. The gene discussed is IL15; the disease is neoplasm.