Cyclooxygenase‐2 is acutely induced by CCAAT/enhancer‐binding protein β to produce prostaglandin E₂ and F_2α following gonadotropin stimulation in Leydig cells

Abstract

Cyclooxygenase 2 (COX‐2) is an inducible rate‐limiting enzyme for prostanoid production. Because COX‐2 represents one of the inducible genes in mouse mesenchymal stem cells upon differentiation into Leydig cells, we investigated COX‐2 expression and production of prostaglandin (PG) in Leydig cells. Although COX‐2 was undetectable in mouse testis, it was transiently induced in Leydig cells by human chorionic gonadotropin (hCG) administration. Consistent with the finding that Leydig cells expressed aldo‐keto reductase 1B7 (PGF synthase) and PGE synthase 2, induction of COX‐2 by hCG caused a marked increase in testicular PGF 2α and PGE 2 levels. Using mouse Leydig cell tumor‐derived MA‐10 cells as a model, it was indicated by reporter assays and electron mobility shift assays that transcription of the COX‐2 gene was activated by CCAAT/enhancer‐binding protein β (C/EBPβ) with cAMP‐stimulation. C/EBPβ expression was induced by cAMP‐stimulation, whereas expression of C/EBP homolog protein (CHOP) was robustly downregulated. Transfection of CHOP expression plasmid inhibited cAMP‐induced COX‐2 promoter activity. In addition, CHOP reduced constitutive COX‐2 expression in other mouse Leydig cell tumor‐derived TM3 cells. These results indicate that COX‐2 is induced in Leydig cells by activation of C/EBPβ via reduction of CHOP expression upon gonadotropin‐stimulation to produce PGF 2α and PGE 2.

Integrative analysis reveals an indirect connection between COX-2/PTGS2 and extracellular matrix proteins in Ch11q-deleted neuroblastoma

“…Although molecular connections among such elements have not been shown for NB yet, other biological models demonstrate their correlation (Supplemental Figure S3). CEBPB andEP300 genes that codify for the C/EBPβ and p300 proteins, respectively, are both activators of PTGS2 transcription 40,41 . IL-1β protein, generated predominantly by tumor-infiltrating macrophages within the tumor microenvironment (TME), has a more functional regulatory role in COX-2 activation, regulating the expression of MMPs 42 , as reported for breast 43 and colorectal cancers 44 .…”

Profiles of 5α-Reduced Androgens in Humans and Eels: 5α-Dihydrotestosterone and 11-Ketodihydrotestosterone Are Active Androgens Produced in Eel Gonads

“…At 24 h or 2 days post-transfection, the cells were treated with vehicle (EtOH) or androgens. Luciferase activity was determined using a dual luciferase reporter assay system ( 29 , 40 ). Measurements were made using a MiniLumat LB9506 (Berthold Systems, Aliquippa, PA, USA) in a single tube, with the first assay involving the firefly luciferase, followed by the Renilla luciferase assay.…”

“…Data are presented as the mean ± SEM. Differences between groups ( P < 0.05) were assessed by the Student’s t -test, one-way ANOVA followed by Tukey’s multiple comparison tests and two-way ANOVA followed by Tukey’s multiple comparison tests using SigmaPlot 14 (Systat Software Inc., CA, USA) and EZR (Saitama Medical Center, Jichi Medical University, Saitama, Japan) which is a graphical user interface for R (The R Foundation for Statistical Computing, Vienna, Austria) as described ( 40 ).…”

“…Total RNA from eel tissues was extracted using TRIsure reagent (Bioline, Luckenwalde, Germany). RT-PCR and qPCR were performed as described (40,42,43). The cDNA was synthesized from total RNA of each tissue using SuperScript III Reverse Transcriptase (Thermo Fisher Scientific).…”

Expression of Chrna9 is regulated by Tbx3 in undifferentiated pluripotent stem cells

“…RT-PCR and qPCR were performed as described. [56][57][58] The RT-PCR products were subjected to electrophoresis on 1.5% (w/v) agarose gels, and the resulting bands were visualized by staining with ethidium bromide. In qPCR, each gene was measured via real-time PCR using the LightCycler 480 (Roche Diagnostics, Mannheim, Germany).…”