TAK1 activation for cytokine synthesis and proliferation of endometriotic cells.
ABSTRACT Endometriosis causes pelvic pain and infertility in women of reproductive age. We explored TNFalpha-induced specific signaling pathways and gene expressions in endometriotic stromal cells (ESCs). Based on the data of the pathway specific cDNA array, we analyzed the role of TAK1, which is believed to work as a common mediator for NF-kappaB and MAPK pathways. Using the NF-kappaB pathway array, we found that TNFalpha upregulated ICAM-3, IL-6, IL-8, TAK1, JNK2, RelA, and TLR4 expressions. TNFalpha augmented the phosphorylation of TAK1. By transfection of TAK1 siRNA, TNFalpha-induced phosphorylation of IkappaBalpha, JNK1/2, and p38MAPK, as well as IL-6 or IL-8 expression, were repressed. TAK1 silencing in TNFalpha-pretreated ESCs caused a decrease in the proportion of cells in S-phase, and reduced TNFalpha-promoted BrdU incorporation. We provide the first evidence that TNFalpha and its downstream TAK1, which are key mediators for NF-kappaB and MAPK pathways, may be involved in the pathogenesis of endometriosis.
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ABSTRACT: Transforming growth factor-β (TGF-β) is believed to play a major role in the aetiology of peritoneal endometriosis. We aimed to determine if the peritoneum is a source of TGF-β and if peritoneal TGF-β expression, reception or target genes are altered in women with endometriosis. Peritoneal fluid, peritoneal bushings and peritoneal biopsies were collected from women with and without endometriosis. TGF-β1, 2 and 3 protein concentrations were measured in the peritoneal fluid. TGF-β1 was measured in mesothelial cell conditioned media. Control peritoneum and peritoneum prone to endometriosis (within Pouch of Douglas) from women without disease (n = 16) and peritoneum distal and adjacent to endometriosis lesions in women with endometriosis (n = 15) and were analysed for TGF-β expression, reception and signalling by immunohistochemistry, qRT-PCR and a TGF-β signalling PCR array. TGF-β1 was increased in the peritoneal fluid of women with endometriosis compared to those without disease (P<0.05) and peritoneal mesothelial cells secrete TGF-β1 in-vitro. In women with endometriosis, peritoneum from sites adjacent to endometriosis lesions expressed higher levels of TGFB1 mRNA when compared to distal sites (P<0.05). The TGF-β-stimulated Smad 2/3 signalling pathway was active in the peritoneum and there were significant increases (P<0.05) in expression of genes associated with tumorigenesis (MAPK8, CDC6), epithelial-mesenchymal transition (NOTCH1), angiogenesis (ID1, ID3) and neurogenesis (CREB1) in the peritoneum of women with endometriosis. In conclusion, the peritoneum, and in particular, the peritoneal mesothelium, is a source of TGF-β1 and this is enhanced around endometriosis lesions. The expression of TGF-β-regulated genes is altered in the peritoneum of women with endometriosis and this may promote an environment favorable to lesion formation.PLoS ONE 09/2014; 9(9):e106773. · 3.53 Impact Factor
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ABSTRACT: B cell development and activation are regulated by combined signals mediated by the B cell receptor (BCR), receptors for the B-cell activating factor of the tumor necrosis factor family (BAFF-R) and the innate receptor, Toll-like receptor 9 (TLR9). However, the underlying mechanisms by which these signals cooperate in human B cells remain unclear. Our aim was to elucidate the key signaling molecules at the crossroads of BCR, BAFF-R and TLR9 mediated pathways and to follow the functional consequences of costimulation.Therefore we stimulated purified human B cells by combinations of anti-Ig, B-cell activating factor of the tumor necrosis factor family (BAFF) and the TLR9 agonist, CpG oligodeoxynucleotide. Phosphorylation status of various signaling molecules, B cell proliferation, cytokine secretion, plasma blast generation and the frequency of IgG producing cells were investigated. We have found that BCR induced signals cooperate with BAFF-R- and TLR9-mediated signals at different levels of cell activation. BCR and BAFF- as well as TLR9 and BAFF-mediated signals cooperate at NFκB activation, while BCR and TLR9 synergistically costimulate mitogen activated protein kinases (MAPKs), ERK, JNK and p38. We show here for the first time that the MAP3K7 (TGF beta activated kinase, TAK1) is responsible for the synergistic costimulation of B cells by BCR and TLR9, resulting in an enhanced cell proliferation, plasma blast generation, cytokine and antibody production. Specific inhibitor of TAK1 as well as knocking down TAK1 by siRNA abrogates the synergistic signals. We conclude that TAK1 is a key regulator of receptor crosstalk between BCR and TLR9, thus plays a critical role in B cell development and activation.PLoS ONE 01/2014; 9(5):e96381. · 3.53 Impact Factor