Regulation of NF-kB in multiple myeloma: therapeutic implications.

The nuclear factor kappa B (NF-kappaB) family of transcription factors plays a major role in inflammation, immune and stress responses, oncogenesis, cell migration, and angiogenesis. Aberrant activation of NF-kappaB has also been shown to contribute to intrinsic and inducible drug resistance in numerous cancers, including multiple myeloma. The expression of NF-kappaB-responsive targets will vary depending on the cellular context and type of inducer. The regulation of NF-kappaB activity occurs at multiple levels involving the IkappaB kinase (IKK) complex, members of the IkappaB family, recruitment of heterologous transcription factors and coactivators by NF-kappaB, and post-translational modifications of p65. This article highlights regulatory mechanisms responsible for constitutive NF-kappaB activation and provides justification for target-based therapy for NF-kappaB in multiple myeloma.