Myeloid-derived suppressor cells (MDSCs) play a crucial role in T cell dysfunction, which is related to poor outcome in patients with severe trauma. Cyclooxygenase-2 (Cox-2) contributes to immune disorder in trauma and infection via production of prostaglandin E2. However, the role of Cox-2 in the accumulation and function of MDSCs after traumatic stress has not been fully elucidated. In the present study, we treated murine trauma model with NS398, a selective Cox-2 inhibitor. Then the percentages of CD11b+/Gr-1+ cells, proliferation and apoptosis of CD4+ T cells were determined. Arginase activity and arginase-1 (Arg-1) protein expression of splenic CD11b+/Gr-1+ cells, and delayed-type hypersensitivity (DTH) response were analyzed. The results showed that Cox-2 blockade significantly decreased the percentages of CD11b+/Gr-1+ cells in the spleen and bone marrow 48 and 72 h after traumatic stress. NS398 inhibited arginase activity and down-regulated the Arg-1 expression of splenic CD11b+/Gr-1+ cells. Moreover, NS398 could promote proliferation and inhibit apoptosis of CD4+ T cells. It also restored DTH response of traumatic mice. Taken together, our data revealed that Cox-2 might play a pivotal role in the accumulation and function of MDSC after traumatic stress.
Animals ; Apoptosis ; drug effects ; Arginase ; biosynthesis ; CD11b Antigen ; biosynthesis ; CD4-Positive T-Lymphocytes ; drug effects ; metabolism ; Cell Proliferation ; drug effects ; Cyclooxygenase 2 ; biosynthesis ; Cyclooxygenase 2 Inhibitors ; administration & dosage ; Gene Expression Regulation ; drug effects ; Humans ; Mice ; Myeloid Progenitor Cells ; metabolism ; pathology ; Nitrobenzenes ; administration & dosage ; Stress Disorders, Traumatic ; drug therapy ; genetics ; pathology ; Sulfonamides ; administration & dosage

OBJECTIVE: To investigate the significance of expression of COX-2, p21, Ki67 and HPV in nasal inverted papilloma. METHOD: Detecting COX-2, p21, Ki-67 in 30 cases of nasal inverted papilloma (NIP), 20 cases of nasal polyps (NP) and 10 cases of normal nasal mucosa (NM) by two step immunohistochemical method, and HPV virus by flow-through hybridization method. RESULT: The positive expression rate of COX-2 and Ki-67 in NIP, NP and NM group was decreased in turn, COX-2 had significant difference in the groups(χ2 = 30.00, P< 0. 05); the positive expression rate of Ki-67 had significant differences between NIP and NM group (χ2 = 8. 533, P<0. 05). The expression of COX-2 in NIP tissues was positively correlate with that of Ki-67 by using Spearman rank correlation analysis (r=0.78, P<0.05). Expression of p21 were not observed in NIP group. The positive rate of HPV was 26. 67% in 30 cases of NIP, all of HPV16 type. CONCLUSION COX-2, Ki-67 and HPV infection have certain correlation with the occurrence of NIP. The occurrence of NIP has relationship with inflammatory reaction mediated by COX-2. Ki-67 can well reflect the proliferation activity of tumor cells, and can be used to measure the proliferation rate of nasal inverted papilloma. The COX-2 and Ki-67 have a synergistic role in the pathogenesis of NIP. p21 has no significant relationship with the incidence of NIP. HPV infection is related to the pathogenesis of NIP, but not as a;major factor in the pathogenesis of NIP.
Case-Control Studies ; Cyclin-Dependent Kinase Inhibitor p21 ; biosynthesis ; Cyclooxygenase 2 ; biosynthesis ; Humans ; Ki-67 Antigen ; biosynthesis ; Nasal Mucosa ; Nasal Polyps ; Nose Neoplasms ; genetics ; virology ; Papilloma, Inverted ; genetics ; virology ; Papillomavirus Infections

BACKGROUNDMechanical stress plays an important role in the maintenance of bone homeostasis. Current hypotheses suggest that interstitial fluid flow is an important component of the system by which tissue level strains are amplified in bone. This study aimed to test the hypothesis that the short-term and appropriate fluid shear stress (FSS) is expected to promote the terminal differentiation of pre-osteoblasts and detect the expression profile of microRNAs in the FSS-induced osteogenic differentiation in MC3T3-E1 cells.

METHODSMC3T3-E1 cells were subjected to 1 hour of FSS at 12 dyn/cm(2) using a parallel plate flow system. After FSS treatment, cytoskeleton immunohistochemical staining and microRNAs (miRNAs) were detected immediately. Osteogenic gene expression and immunohistochemical staining for collagen type I were tested at the 24th hour after treatment, alkaline phosphatase (ALP) activity assay was performed at 24th, 48th, and 72 th hours after FSS treatment, and Alizarin Red Staining was checked at day 12.

RESULTSOne hour of FSS at 12 dyn/cm(2) induced actin stress fiber formation and rearrangement, up-regulated osteogenic gene expression, increased ALP activity, promoted synthesis and secretion of type I collagen, enhanced nodule formation, and promoted terminal differentiation in MC3T3-E1 cells. During osteogenic differentiation, expression levels of miR-20a, -21, -19b, -34a, -34c, -140, and -200b in FSS-induced cells were significantly down-regulated.

CONCLUSIONThe short-term and appropriate FSS is sufficient to promote terminal differentiation of pre-osteoblasts and a group of miRNAs may be involved in FSS-induced pre-osteoblast differentiation.

Actins ; chemistry ; Alkaline Phosphatase ; metabolism ; Animals ; Cell Differentiation ; Cells, Cultured ; Collagen Type I ; biosynthesis ; Core Binding Factor Alpha 1 Subunit ; genetics ; Cyclooxygenase 2 ; genetics ; Gene Expression Profiling ; Mice ; MicroRNAs ; physiology ; Osteoblasts ; cytology ; Osteogenesis ; Stress, Mechanical ; Stress, Physiological

The effect of extracellular beta-(1-->3), (1-->6)-glucan, produced by Paenibacillus polymyxa JB115, on nitric oxide (NO) production in RAW264.7 macrophages was investigated. beta-glucan induced the production of NO by RAW264.7 macrophages in a concentration- and time-dependent manner. Moreover, beta-glucan stimulation increased the mRNA expression of iNOS, COX-2 and IL-6 in RAW264.7 macrophages in a concentration-dependent manner.
Animals ; Bacillus/*metabolism ; Cell Line ; Cyclooxygenase 2/biosynthesis/genetics ; Interleukin-6/biosynthesis/genetics ; Lipopolysaccharides/pharmacology ; Macrophages/*drug effects/enzymology/immunology ; Mice ; Nitric Oxide/*biosynthesis/immunology ; Nitric Oxide Synthase Type II/biosynthesis/genetics/metabolism ; RNA, Messenger/biosynthesis/genetics ; Reverse Transcriptase Polymerase Chain Reaction ; beta-Glucans/metabolism/*pharmacology

Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) is a tumor suppressor. Although it is well known to have various physiological roles in cancer, its inhibitory effect on inflammation remains poorly understood. In the present study, a human PTEN gene was fused with PEP-1 peptide in a bacterial expression vector to produce a genetic in-frame PEP-1-PTEN fusion protein. The expressed and purified PEP-1-PTEN fusion protein were transduced efficiently into macrophage Raw 264.7 cells in a time- and dose- dependent manner when added exogenously in culture media. Once inside the cells, the transduced PEP-1-PTEN protein was stable for 24 h. Transduced PEP-1-PTEN fusion protein inhibited the LPS-induced cyclooxygenase 2 (COX-2) and iNOS expression levels in a dose-dependent manner. Furthermore, transduced PEP-1-PTEN fusion protein inhibited the activation of NF-kappa B induced by LPS. These results suggest that the PEP-1-PTEN fusion protein can be used in protein therapy for inflammatory disorders.
Animals ; Cell Line ; Cyclooxygenase 2/*metabolism ; Cysteamine/*analogs & derivatives ; Enzyme Activation ; Humans ; Lipopolysaccharides/*pharmacology ; Macrophages/*metabolism ; Mice ; NF-kappa B/metabolism ; Nitric Oxide/*biosynthesis ; Nitric Oxide Synthase Type II/metabolism ; PTEN Phosphohydrolase/*genetics ; Peptides/*genetics ; Recombinant Fusion Proteins/*biosynthesis/genetics ; Signal Transduction

Cyclooxygenase-2 (COX-2) is known to modulate bone metabolism, including bone formation and resorption. Because cartilage serves as a template for endochondral bone formation and because cartilage development is initiated by the differentiation of mesenchymal cells into chondrocytes (Ahrens et al., 1977; Sandell and Adler, 1999; Solursh, 1989), it is of interest to know whether COX-2 expression affect chondrocyte differentiation. Therefore, we investigated the effects of COX-2 protein on differentiation in rabbit articular chondrocyte and chick limb bud mesenchymal cells. Overexpression of COX-2 protein was induced by the COX-2 cDNA transfection. Ectopic expression of COX-2 was sufficient to causes dedifferentiation in articular chondrocytes as determined by the expression of type II collagen via Alcian blue staining and Western blot. Also, COX-2 overexpression caused suppression of SOX-9 expression, a major transcription factor that regulates type II collagen expression, as indicated by the Western blot and RT-PCR. We further examined ectopic expression of COX-2 in chondrifying mesenchymal cells. As expected, COX-2 cDNA transfection blocked cartilage nodule formation as determined by Alcian blue staining. Our results collectively suggest that COX-2 overexpression causes dedifferentiation in articular chondrocytes and inhibits chondrogenic differentiation of mesenchymal cells.
Animals ; Cartilage, Articular/cytology ; Cell Differentiation ; Cells, Cultured ; Chick Embryo ; Chondrocytes/*cytology/enzymology ; Chondrogenesis ; Collagen Type II/metabolism ; Cyclooxygenase 2/*biosynthesis/genetics ; Interleukin-1beta/pharmacology ; Mesenchymal Stem Cells/*cytology/enzymology ; Rabbits ; SOX9 Transcription Factor/metabolism

OBJECTIVETo determine the levels of MMP-2 and COX-2 mRNA in bladder transitional cell carcinoma tissues and explore their relationship.

METHODSWe enrolled in this study 42 patients with bladder transitional cell carcinoma, including Ta-T1 (n = 18), T2-T4 (n = 24), G1 (n = 12), G2 (n = 19), G3 (n = 11), metastasis (n =26) and non-metastasis (n = 16). Another 5 cases of normal bladder tissues were taken as controls, and the levels of MMP-2 and COX-2 mRNA were detected by RT-PCR.

RESULTSThe relative expressions of COX-2 mRNA were 1.038 +/- 0. 484 in Ta-T1, 1.489 +/- 0.584 in T2-T4, 0.920 +/- 0.442 in G1, 1.338 +/- 0.584 in G2 and 1.632 +/- 0.515 in G3, all significantly higher than that of the controls (0.460 +/- 0.224, P < 0.05). And the corresponding relative levels of MMP-2 mRNA were 1.107 +/- 0.384, 1.604 +/- 0.425, 0.971 +/- 0.370, 1.445 +/- 0.378 and 1.755 +/- 0.387, also significantly higher than that of the latter group (0.423 +/- 0.227, P < 0.05). The COX-2 and MMP-2 mRNA levels in the tumor tissues with and without metastasis were 1.591 +/- 0.455 vs 0.815 +/- 0.430 and 1.676 +/- 0.339 vs 0.927 +/- 0.228, (P < 0.01), respectively, with a positive correlation between the mRNA level of COX-2 and that of MMP-2 (r = 0. 703, P < 0.01).

CONCLUSIONMMP-2 and COX-2 mRNA are highly expressed in bladder transitional cell carcinoma tissues and their expressions are positively correlated with the degree of malignancy. MMP-2 and COX-2 might play a synergetic role in the pathogenesis and progression of bladder transitional cell carcinoma.

Adult ; Aged ; Carcinoma, Transitional Cell ; metabolism ; pathology ; Cyclooxygenase 2 ; biosynthesis ; genetics ; Female ; Humans ; Matrix Metalloproteinase 2 ; biosynthesis ; genetics ; Middle Aged ; Neoplasm Staging ; RNA, Messenger ; genetics ; Urinary Bladder Neoplasms ; metabolism ; pathology

OBJECTIVETo investigate the effects of cyclooxygenase inhibitor diclofenac on the proliferation and cyclooxygenase-2 (COX-2) mRNA expression of cultured hepatocellular carcinoma cell lines HepG2, Hep3B and human hepatocellular cell line QSG-7701.

METHODSAfter exposure to diclofenac at various concentrations (10-200 micromol/L) for 24, 48 and 72 h, the cell proliferation was analyzed by Cell Counting Kit-8 (CCK-8) assay and mRNA expression determined by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR).

RESULTSDiclofenac exposure for 24, 48 and 72 h significantly inhibited HepG2 and Hep3B cell proliferation in a concentration-dependent manner, with inhibition rate of 40.47% and 54.49% after 48 h exposure to 50 micromol/L diclofenac and IC50 of 70.54 and 48.39 micromol/L, respectively. A much weaker antiproliferative effect on QSG-7701 cells was shown, with IC50 of 189.91 micromol/L after 48-hour exposure to diclofenac. RT-PCR detected COX-2 mRNA in HepG2 and Hep3B cells, but hardly in QSG-7701 cells. Treatment with diclofenac or 5-Fu resulted in elevated COX-2 mRNA expression both in HepG2 and Hep3B cells.

CONCLUSIONDiclofenac can specifically inhibit the proliferation of COX-2-expressing HepG2 and Hep3B cells, and induce up-regulation of COX-2 mRNA expression, which indicates the important role of COX-2 in the proliferation of hepatoma cells.

Carcinoma, Hepatocellular ; enzymology ; genetics ; pathology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cyclooxygenase 2 ; genetics ; Cyclooxygenase Inhibitors ; pharmacology ; Diclofenac ; pharmacology ; Gene Expression Regulation, Enzymologic ; drug effects ; Humans ; Liver Neoplasms ; enzymology ; genetics ; pathology ; RNA, Messenger ; biosynthesis ; genetics ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo investigate cyclooxygenase-2 (COX-2) expression of in colorectal carcinoma cell lines and tissues and its clinical implications.

METHODSSP immunohistochemistry was used to detect COX-2 protein in SW480 and SW620 cell lines and 50 primary colorectal carcinoma and 50 lymphoma metastasis carcinoma specimens. Real-time PCR was used to detect COX-2 mRNA expression in SW480 and SW620 cell lines.

RESULTSSW480 and SW620 cell lines both highly expressed COX-2. The positive expression levels of COX-2 increased significantly in lymph node metastatic carcinoma in comparison with primary colorectal carcinoma (P<0.05). The expression COX-2 mRNA in SW620 cell line was higher than that of SW480 cell line, showing a mean expression increment of 2.268 folds in SW620 cell line relative to SW480.

CONCLUSIONElevated COX-2 expression may be associated with lymph node metastases of colorectal carcinoma.

Cell Line, Tumor ; Colorectal Neoplasms ; enzymology ; pathology ; Cyclooxygenase 2 ; biosynthesis ; genetics ; Gene Expression Regulation, Enzymologic ; Gene Expression Regulation, Neoplastic ; Humans ; Immunohistochemistry ; Lymphatic Metastasis ; RNA, Messenger ; biosynthesis ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo observe the changes in gene expression of cyclooxygenase (COX) during spontaneous recovery from stress ulcer in rats exposed to water immersion and restraint stress (WRS).

METHODSA rat model of stress ulcer was established by means of WRS, in which the changes in COX expression were detected with immunohistochemistry and reverse transcription (RT)-PCR.

RESULTSVery low levels of COX-2 expression were detected in the gastric mucosa of the control rats, and the expression increased significantly during the healing process of the stress ulcer (P<0.05). COX-1 expression in the gastric mucosa showed no significant difference between the control group and the stress ulcer groups during healing (P>0.05).

CONCLUSIONCOX-1 and COX-2 expressions in rat gastric mucosa during the recovery from stress ulcer participate in the recovery of the damaged mucosa possibly by mediating prostaglandin secretion.

Animals ; Cyclooxygenase 1 ; biosynthesis ; genetics ; Cyclooxygenase 2 ; biosynthesis ; genetics ; Gastric Mucosa ; enzymology ; Male ; Prostaglandin-Endoperoxide Synthases ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Remission, Spontaneous ; Stomach Ulcer ; enzymology ; Stress, Physiological ; complications