GZMB and neoplasm: This effect can be blocked by treatment with propranolol or via using β2-receptor knockout mice, thus resulting in the restoration of anti-tumor immunity as evidenced by increased expression of markers of effector function (T-bet, IFNγ, and GzmB) and a significantly increased ratio of IFNγ+ CD8+: Treg cells indicative of an inflammatory tumor microenvironment (TME).