CD4 and lung cancer: In addition, CD8+ T cells of ibrutinib-treated mice displayed increased production of Granzyme B (Fig. 5d, h), which is perhaps not surprising as activated CD8+ T cells produce Granzyme B36 to suppress metastasis in breast and lung cancers.37 We also found that CD4+ T cells from ibrutinib-treated mice produce more IL-2 and IFN-γ compared to controls, but the differences were statistically not significant (data are not shown).