NFKB1 and breast cancer: Second, TG2 reportedly facilitates the nuclear translocation of NF-κB, regardless of its enzymatic activity in breast cancer cells.27 In contrast to this report, our data show that the expression of enzymatically inactive TG2 failed to increase the expression of proinflammatory cytokines after UV irradiation, demonstrating that the transamidation activity of TG2 is required for UV-induced NF-κB activation.