Nonetheless, evidence for β-AR-dependent increase of NK cytotoxicity has been obtained in rats treated with amphetamine (Glac et al., 2006) and more recently it has been shown that also repeated social disruption in mice “primes” NK cells in the spleen and lung to be more proficient in their cytolytic and anti-viral/tumor effecter functions through β-AR activation (Tarr et al., 2012). This evidence concerns the gene ADRB2 and neoplasm.