The differential expression of two closelyassociated cyclooxygenase isozymes, COX-1 and COX-2, exhibited functions beyond eicosanoid metabolism. We hypothesized that COX-1 or COX-2 knockout lung fibroblasts may displa...The differential expression of two closelyassociated cyclooxygenase isozymes, COX-1 and COX-2, exhibited functions beyond eicosanoid metabolism. We hypothesized that COX-1 or COX-2 knockout lung fibroblasts may display altered protein profiles which may allow us to further differentiate the functional roles of these isozymes at the molecular level. Proteomic analysis shows constitutive production of macrophage migration inhibitory factor （MIF） in lung fibroblasts derived from COX-2 / but not wild-type （WT） or COX-1-/- mice. MIF was spontaneously released in high levels into the extracellular milieu of COX2 /- fibroblasts seemingly from the pre- formed intracellular stores, with no change in the basal gene expression of MIF. The secretion and regulation of MIF in COX-2-/- was ＂prostaglandin-independent.＂ GO analysis showed that concurrent with upregulation of MIF, there is a significant surge in expression of genes related to fibroblast growth, FK506 binding proteins, and isomerase activity in COX-2 ! cells. Furthermore, COX-2-/- fibroblasts also exhibit a significant increase in transcriptional activity of various regu- lators, antagonists, and co-modulators of p53, as well as in the expression of oncogenes and related transcripts. Integrative Oncogenomics Cancer Browser （IntroGen） analysis shows downregulation of COX-2 and amplification of MIF and/or p53 activity during development of glioblastomas, ependymoma, and colon adenomas. These data indicate the functional role of the MIF-COX- p53 axis in inflammation and cancer at the genomic and proteomie levels in COX-2-ablated cells. This systematic analysis not only shows the proinflammatory state but also unveils a molecular signature of a pro-oncogenic state of COX-1 in COX-2 ablated cells.展开更多
The constitutively-expressed cyclooxygenase 1（COX-1） and the inducible COX-2 are both involved in the conversion of arachidonic acid（AA） to prostaglandins（PGs）.However,the functional roles of COX-1 at the cellul...The constitutively-expressed cyclooxygenase 1（COX-1） and the inducible COX-2 are both involved in the conversion of arachidonic acid（AA） to prostaglandins（PGs）.However,the functional roles of COX-1 at the cellular level remain unclear.We hypothesized that by comparing differential gene expression and eicosanoid metabolism in lung fibroblasts from wild-type（WT） mice and COX-2^（-/-） or COX-1^（-/-） mice may help address the functional roles of COX-1 in inflammation and other cellular functions.Compared to WT,the number of specifically-induced transcripts were altered descendingly as follows：COX-2^（-/-） 〉 COX-1^（-/-） 〉 WT ＋ IL-1β.COX-1^（-/-） or COX-2^（-/-） cells shared about 50%of the induced transcripts with WT cells treated with IL-1β,respectively.An interactive ＂anti-inflammatory,proinflammatory,and redox-activated＂ signature in the protein-protein interactome map was observed in COX-2^（-/-） cells.The augmented COX-1mRNA（in COX-2^（-/-） cells） was associated with the upregulation of mRNAs for glutathione S-transferase（GST）,superoxide dismutase（SOD）,NAD（P）H dehydrogenase quinone 1（NQO1）,aryl hydrocarbon receptor（AhR）,peroxiredoxin,phospholipase,prostacyclin synthase,and prostaglandin E synthase,resulting in a significant increase in the levels of PGE2,PGD2,leukotriene B4（LTB4）,PGF（1α）,thromboxane B2（TXB2）,and PGF（2α）.The COX-1 plays a dominant role in shifting AA toward the LTB4 pathway and anti-inflammatory activities.Compared to WT,the upregulated COX-1 mRNA in COX-2^（-/-） cells generated an ＂eicosanoid storm＂.The genomic characteristics of COX-2^（-/-） is similar to that of proinflammatory cells as observed in IL-1β induced WT cells.COX-1^（-/-） and COX-2^（-/-） cells exhibited compensation of various eicosanoids at the genomic and metabolic levels.展开更多
基金supported by the National Institutes of Health of the United States(Grant Nos.NS051715,AR 47206-03,and AG030539)Yamanuchi[Astellas]Pharmaceuticals,Japan
文摘The differential expression of two closelyassociated cyclooxygenase isozymes, COX-1 and COX-2, exhibited functions beyond eicosanoid metabolism. We hypothesized that COX-1 or COX-2 knockout lung fibroblasts may display altered protein profiles which may allow us to further differentiate the functional roles of these isozymes at the molecular level. Proteomic analysis shows constitutive production of macrophage migration inhibitory factor （MIF） in lung fibroblasts derived from COX-2 / but not wild-type （WT） or COX-1-/- mice. MIF was spontaneously released in high levels into the extracellular milieu of COX2 /- fibroblasts seemingly from the pre- formed intracellular stores, with no change in the basal gene expression of MIF. The secretion and regulation of MIF in COX-2-/- was ＂prostaglandin-independent.＂ GO analysis showed that concurrent with upregulation of MIF, there is a significant surge in expression of genes related to fibroblast growth, FK506 binding proteins, and isomerase activity in COX-2 ! cells. Furthermore, COX-2-/- fibroblasts also exhibit a significant increase in transcriptional activity of various regu- lators, antagonists, and co-modulators of p53, as well as in the expression of oncogenes and related transcripts. Integrative Oncogenomics Cancer Browser （IntroGen） analysis shows downregulation of COX-2 and amplification of MIF and/or p53 activity during development of glioblastomas, ependymoma, and colon adenomas. These data indicate the functional role of the MIF-COX- p53 axis in inflammation and cancer at the genomic and proteomie levels in COX-2-ablated cells. This systematic analysis not only shows the proinflammatory state but also unveils a molecular signature of a pro-oncogenic state of COX-1 in COX-2 ablated cells.
文摘The constitutively-expressed cyclooxygenase 1（COX-1） and the inducible COX-2 are both involved in the conversion of arachidonic acid（AA） to prostaglandins（PGs）.However,the functional roles of COX-1 at the cellular level remain unclear.We hypothesized that by comparing differential gene expression and eicosanoid metabolism in lung fibroblasts from wild-type（WT） mice and COX-2^（-/-） or COX-1^（-/-） mice may help address the functional roles of COX-1 in inflammation and other cellular functions.Compared to WT,the number of specifically-induced transcripts were altered descendingly as follows：COX-2^（-/-） 〉 COX-1^（-/-） 〉 WT ＋ IL-1β.COX-1^（-/-） or COX-2^（-/-） cells shared about 50%of the induced transcripts with WT cells treated with IL-1β,respectively.An interactive ＂anti-inflammatory,proinflammatory,and redox-activated＂ signature in the protein-protein interactome map was observed in COX-2^（-/-） cells.The augmented COX-1mRNA（in COX-2^（-/-） cells） was associated with the upregulation of mRNAs for glutathione S-transferase（GST）,superoxide dismutase（SOD）,NAD（P）H dehydrogenase quinone 1（NQO1）,aryl hydrocarbon receptor（AhR）,peroxiredoxin,phospholipase,prostacyclin synthase,and prostaglandin E synthase,resulting in a significant increase in the levels of PGE2,PGD2,leukotriene B4（LTB4）,PGF（1α）,thromboxane B2（TXB2）,and PGF（2α）.The COX-1 plays a dominant role in shifting AA toward the LTB4 pathway and anti-inflammatory activities.Compared to WT,the upregulated COX-1 mRNA in COX-2^（-/-） cells generated an ＂eicosanoid storm＂.The genomic characteristics of COX-2^（-/-） is similar to that of proinflammatory cells as observed in IL-1β induced WT cells.COX-1^（-/-） and COX-2^（-/-） cells exhibited compensation of various eicosanoids at the genomic and metabolic levels.
