IKKb/IKBKB (IkB kinase beta), also designated as IKK2, was named after its function of phosphorylating IkB molecules, the inhibitors of NF-kB transcription factors. The kinase activity of IKKb targets two adjacent serine residues of IkB leading to ubiquitination and proteasomal degradation of the inhibitor, followed by release and activation of NF-kB. Many signaling pathways that activate NF-kB...

Current understanding of nuclear factor-kB (NF-kB) activation is derived mostly from in vitro studies, and in vivo human data are limited. This study provides first evidence showing that physical exercise (80% maximal O2 consumption, 1 h) may trigger NF-kB activation, as determined by electrophoretic mobility shift assay, in peripheral blood lymphocytes of physically fit young men. Supershift a...

BACKGROUND Nuclear factor-kappaB (NF-kB), a transcription factor, is abundantly expressed in prostate cancer and regulates many tumor-related genes. Given the important roles of these genes in tumor control, the present study was conducted to test the hypothesis that there was different expression of NF-kB in androgen- dependent or androgen-independent prostate cancer cells. In addition NF-kB d...

Inhibitor-kB kinase « (IKK«) was only recently identified as an enzyme with high homology to the classical I-kB kinase subunits, IKKa and IKKb. Despite this similarity, it is mainly discussed as a repressor of viral infections by modulating type I IFNs. However, in vitro studies also showed that IKK« plays a role in the regulation of NF-kB activity, but the distinct mechanisms of IKK«-mediated ...

The ubiquitin-editing protein A20 limits the duration of NF-kB activation and is essential to control inflammatory responses. Recent experiments have established that A20 mediates its inhibitory function in a complex with two other proteins, TAX1BP1 and the E3 ligase Itch. In a paper published in this issue, it is shown that RNF11 is also a critical component of the A20 ubiquitin-editing comple...

Pregnane X receptor (PXR) activation exhibits anti-inflammatory effects via repressing nuclear factor-kB (NF-kB); however, its overactivation may disrupt homeostasis of various enzymes and transporters. Here we found that ginsenosides restore PXR/NFkB signaling in inflamed conditions without disrupting PXR function in normal conditions. The effects and mechanisms of ginsenosides in regulating P...

We hypothesized that a redox-sensitive transcription factor, redox factor-1 (Ref-1) (HAP1, APE, and APEX), was critical in the regulation of endothelial cell survival in response to hypoxia and cytokines, including tumor necrosis factor (TNF)-a. Hypoxia resulted in a significant decrease in Ref-1 protein expression in both human umbilical vein endothelial cells and calf pulmonary artery endothe...

We hypothesized that a redox-sensitive transcription factor, redox factor-1 (Ref-1) (HAP1, APE, and APEX), was critical in the regulation of endothelial cell survival in response to hypoxia and cytokines, including tumor necrosis factor (TNF)-a. Hypoxia resulted in a significant decrease in Ref-1 protein expression in both human umbilical vein endothelial cells and calf pulmonary artery endothe...

N-(4-hydroxyphenyl) retinamide [4-HPR], a synthetic retinoid, has been shown to inhibit tumor cell growth, invasion, and metastasis by a mechanism that is not fully understood. Because the nuclear factor-KB (NF-KB) has also been shown to regulate proliferation, invasion, and metastasis of tumor cells, we postulated that 4-HPR modulates the activity of NF-KB. To test this postulate, we examined ...

The Rel/nuclear factor (NF)-kB family of transcription factors are important intracellular conveyors of extracellular signals in a number of systems. However, little is known of their roles in the specialized, hormonally regulated environment of the mammalian testis. In this study NF-kB p50 and p65 proteins were found to be constitutively present and active in the nucleus of Sertoli cells cultu...