To further validate the significance of NK cells’ secreted cytokines and/or rhIFN-γ and rhTNF-α in inducing differentiation in lung cancer, we treated tumors with antibodies against both IFN-γ and TNF-α to determine if we can block the NK cell- or rIFN-γ- and rTNF-α-induced differentiation of hA549. Here, TNF is linked to lung cancer.