GZMB and neoplasm: Although it leads to a significant block of tumor progression, it affects the function of NK cells including proliferation (due to the blocking of the PI3K/AKT pathway), production of effector molecules (such as perforin and granzyme B), cytokines (including TNF-α and IFN-γ) and NK-cell mediated cytotoxicity in response to tumor targets, due to impaired ERK phosphorylation [183].