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Inan, Mehmet Sait, Veronica Tolmacheva, Qiang-Shu Wang, Daniel W. Rosenberg, and Charles Giardina. Transcription factor NF-[Kappa]B participates in regulation of epithelial cell turnover in the colon. Am J Physiol Gastrointest Liver Physiol 279: G1282-G1291, 2000.--The transcription factor nuclear factor (NF)-[Kappa]B regulates the expression of genes that can influence cell proliferation and death. Here we analyze the contribution of NF-[Kappa]B to the regulation of epithelial cell turnover in the colon. Immunohistochemical, immunoblot, and DNA binding analyses indicate that NF-[Kappa]B complexes change as colonocytes mature: p65-p50 complexes predominate in proliferating epithelial cells of the colon, whereas the p50-p50 dimer is prevalent in mature epithelial cells. NF-[Kappa]B1 (p50) knockout mice were used to study the role of NF-[Kappa]B in regulating epithelial cell turnover. Knockout animals lacked detectable NF-[Kappa]B DNA binding activity in isolated epithelial cells and had significantly longer crypts with a more extensive proliferative zone than their wild-type counterparts (as determined by proliferating cell nuclear antigen staining and in vivo bromodeoxyuridine labeling). Gene expression profiling reveals that the NF-[Kappa]B1 knockout mice express the potentially growth-enhancing tumor necrosis factor (TNF)-[Alpha]. and nerve growth factor-[Alpha], genes at elevated levels, with in situ hybridization localizing some of the TNF-[Alpha]. expression to epithelial cells. TNF-[Alpha]. is NF-[Kappa]B regulated, and its upregulation in NF-[Kappa]B1 knockouts may result from an alleviation of p50-p50 repression. NF-[Kappa]B complexes may therefore influence cell proliferation in the colon through their ability to selectively activate and/or repress gene expression. nuclear factor-[Kappa]B; cell proliferation; tumor necrosis factor-[Alpha] nerve growth factor-[Alpha]

Empty follicle syndrome (EFS) is characterized by the absence of oocytes after apparently normal follicular development and the pathogenesis of this syndrome is not well characterized. The aim of this study was to analyse whole gene expression of granulosa cells (GC) from a patient with recurrent EFS by using Affymetrix GeneChip. A total of 160 genes were identified as being differentially expressed (by at least two-fold) between EFS GC and the control GC. Most of the differentially expressed genes were involved in cell growth and death. Among these were MAPK3, which plays an important role in the inhibition of apoptosis, was down-regulated 2.3-fold in EFS GC. Moreover, secretory phospholipase A2 and transforming growth factor receptor H, key regulators of cell death pathway, were down-regulated 3.54- and 2.82-fold respectively in EFS. Gene expression of granulosa cells from the EFS patient was significantly altered. The absence of the oocytes might be due to the increased apoptotic gene expression and the reduction of transcripts whose products are responsible for healthy follicular growth. Gene expression analyses might be a useful technique in identifying markers to follow a healthy follicular maturation and understanding the events that lead to EFS. [ABSTRACT FROM AUTHOR]

Analyzes the contribution of transcription factor nuclear factor-kappa B to the regulation of epithelial cell turnover in the colon. Protein expression and nuclear factor-kappa B activity in isolated populations of colonic epithelial cells; Expression of nuclear factor-kappa B subunits p50 and p65 in isolated epithelial cells.

Objective: To investigate the expression of the novel Ets transcription factor ESE-1 in rheumatoid synovium and in cells derived from joint tissues, and to analyze the role of nuclear factor kappaB (NF-kappaB) as one of the central downstream targets in mediating the induction of ESE-1 by proinflammatory cytokines., Methods: ESE-1 protein expression was analyzed by immunohistochemistry using antibodies in synovial tissues from patients with rheumatoid arthritis (RA) and osteoarthritis (OA). ESE-1 messenger RNA (mRNA) levels were analyzed by reverse transcriptase-polymerase chain reaction or Northern blotting in human chondrocytes, synovial fibroblasts, osteoblasts, and macrophages, before and after exposure to interleukin-1beta (IL-1beta), tumor necrosis factor alpha (TNFalpha), or lipopolysaccharide (LPS) with or without prior infection with an adenovirus encoding the inhibitor of nuclear factor kappaB (IkappaB). The wild-type ESE-1 promoter and the ESE-1 promoter mutated in the NF-kappaB site were cloned into a luciferase reporter vector and analyzed in transient transfections. Electrophoretic mobility shift assays (EMSAs) and supershift assays with antibodies against members of the NF-kappaB family were conducted using the NF-kappaB site from the ESE-1 promoter as a probe., Results: Immunohistochemical analysis showed specific expression of ESE-1 in cells of the synovial lining layer and in some mononuclear and endothelial cells in RA and OA synovial tissues. ESE-1 mRNA expression could be induced by IL-1beta and TNFalpha in cells such as synovial fibroblasts, chondrocytes, osteoblasts, and monocytes. Transient transfection experiments and EMSAs showed that induction of ESE-1 gene expression by IL-1beta requires activation of NF-kappaB and binding of p50 and p65 family members to the NF-kappaB site in the ESE-1 promoter. Overexpression of IkappaB using an adenoviral vector blocked IL-1beta-induced ESE-1 mRNA expression. Chromatin immunoprecipitation further confirmed that NF-kappaB binds to the ESE-1 promoter in vivo., Conclusion: ESE-1 is expressed in synovial tissues in RA and, to a variable extent, in OA, and is specifically induced in synovial fibroblasts, chondrocytes, osteoblasts, and monocyte/macrophages by IL-1beta, TNFalpha, or LPS. This induction relies on the translocation of the NF-kappaB family members p50 and p65 to the nucleus and transactivation of the ESE-1 promoter via a high-affinity NF-kappaB binding site. ESE-1 may play a role in mediating some effects of proinflammatory stimuli in cells at sites of inflammation.