Furthermore, we determined after short-term in vitro leptin stimulation the phosphorylation of JAK2, downstream target of the intracellular signaling cascade of the leptin receptor, by Western Blotting and numbers of NK-cell-tumor-cell-conjugates as well as Granzyme+ and IFN-γ+ NK cells by flow cytometry. The gene discussed is LEPR; the disease is neoplasm.