HMOX1 and neoplasm: The effect observed when we employed the HO-1 inhibitor on IFN-γ and TNF-α production in CD107a + NK-92 cells co-cultured with CCC was important because IFN-γ and TNF-α produced by NK cells can induce apoptosis in tumor cells by means of interaction with localized cell-death receptors in tumor cells or through stimulation of cytotoxicity activity in CD8+ cells, in addition to helping to differentiate CD4+ T cells toward a Th1 response to promote CD8+ cell differentiation and to promote antitumor antibody production by B cells [47-50].