NF-B signaling in neoplastic transition from epithelial to mesenchymal phenotype

NF-kappa B transcription factors are critical regulators of innate and adaptive immunity and major mediators of inflammatory signaling. The NF-kappa B signaling is dysregulated in a significant number of cancers and drives malignant transformation through maintenance of constitutive pro-survival signaling and downregulation of apoptosis. Overactive NF-kappa B signaling results in overexpression of pro-inflammatory cytokines, chemokines and/or growth factors leading to accumulation of proliferative signals together with activation of innate and select adaptive immune cells. This state of chronic inflammation is now thought to be linked to induction of malignant transformation, angiogenesis, metastasis, subversion of adaptive immunity, and therapy resistance. Moreover, accumulating evidence indicates the involvement of NF-kappa B signaling in induction and maintenance of invasive phenotypes linked to epithelial to mesenchymal transition (EMT) and metastasis. In this review we summarize reported links of NF-kappa B signaling to sequential steps of transition from epithelial to mesenchymal phenotypes. Understanding the involvement of NF-kappa B in EMT regulation may contribute to formulating optimized therapeutic strategies in cancer.