Lactate inhibits NK cell activity and immune function through a dual mechanism: on the one hand, the accumulation of lactic acid diminishes the cytotoxic and secretory functions by downregulation expression of activated receptors such as NKp46, CD107a and NKG2D of NK cells, thereby blocking tumor recognition signals [144, 145, 146]. The gene discussed is KLRK1; the disease is neoplasm.