Constitutive activation of the canonical NF-κB signaling pathway in EBV-associated gastric carcinoma.

EBV-associated gastric carcinoma (EBVaGC) is a specific subgroup of gastric carcinoma, and the multifunctional transcriptional factor NF-κB may contribute to its tumorigenesis. In this study, we comprehensively characterized NF-κB signaling in EBVaGC using qRT-PCR, western blot, immunofluorescence assays, ELISA, and immunohistochemistry staining. NF-κB-signaling inhibitors may inhibit the growth of EBVaGC cells and induce significant apoptosis. IκBα is a key regulatory molecule, and repression of IκBα can contribute to aberrant NF-κB activation. Overexpression of LMP1 and LMP2A in the EBV-negative GC cell line SGC7901 could inhibit the expression of IκBα and induce NF-κB activation. These findings indicate that the canonical NF-κB signal is constitutively activated and plays an important role in EBVaGC tumorigenesis.