Expression of the CD117, COX-2 and HSP90 antigens and cell proliferation in fine-needle-aspirated cells from metastatic melanomas

BACKGROUND

Blocking therapies aimed at COX-2, HSP90 and CD117 have been described recently. The objective of the study was to analyze expression of these antigens and the proliferation rate in metastatic melanomas.

MATERIALS AND METHODS

Fine-needle aspirates from 30 patients were analyzed. Immunocytochemical methods were applied to assess COX-2, HSP-90 and CD117. Cell proliferation was analysed using expression of Ki-67. Findings were compared with histopathological parameters.

RESULTS

All cases expressed COX-2 and HSP90. CD117 was expressed in 46% of cases. The proliferation index ranged between 7% and 54%. No correlation was found between histological properties of the primary tumours and expression of CD117, COX-2 and HSP90 in their metastases. An inverse correlation was found between HSP90 and MIB-1 index.

CONCLUSION

A large proportion of metastatic melanomas expressed COX-2 and HSP90. This may have a clinical implication for blocking therapy of the corresponding molecules. Expression of CD117 antigen was observed in only 5/30 melanoma cases. We hypothesize that such melanomas may benefit from targeted therapy with kinase inhibitors.

Characterization of Gaucher disease bone marrow mesenchymal stromal cells reveals an altered inflammatory secretome

Gaucher disease causes pathologic skeletal changes that are not fully explained. Considering the important role of mesenchymal stromal cells (MSCs) in bone structural development and maintenance, we analyzed the cellular biochemistry of MSCs from an adult patient with Gaucher disease type 1 (N370S/L444P mutations). Gaucher MSCs possessed a low glucocerebrosidase activity and consequently had a 3-fold increase in cellular glucosylceramide. Gaucher MSCs have a typical MSC marker phenotype, normal osteocytic and adipocytic differentiation, growth, exogenous lactosylceramide trafficking, cholesterol content, lysosomal morphology, and total lysosomal content, and a marked increase in COX-2, prostaglandin E2, interleukin-8, and CCL2 production compared with normal controls. Transcriptome analysis on normal MSCs treated with the glucocerebrosidase inhibitor conduritol B epoxide showed an up-regulation of an array of inflammatory mediators, including CCL2, and other differentially regulated pathways. These cells also showed a decrease in sphingosine-1-phosphate. In conclusion, Gaucher disease MSCs display an altered secretome that could contribute to skeletal disease and immune disease manifestations in a manner distinct and additive to Gaucher macrophages themselves.

Tumor necrosis factor-alpha-induced cyclooxygenase-2 overexpression in eutopic endometrium of women with endometriosis by stromal cell culture through nuclear factor-kappaB activation

OBJECTIVE

To investigate the role of NF-kappaB during the induction of COX-2 by TNF-alpha in the eutopic endometrium of women with and without endometriosis using stromal cell culture.

STUDY DESIGN

Experimental study in cultured stromal cells of the eutopic endometrium of women with and without endometriosis in the presence of TNF-alpha.

RESULTS

Within 5-20 minutes of stimulation with TNF-alpha, p-IkappaB was clearly observed in the eutopic endometrium of women with endometriosis and in that of women without endometriosis. COX-2 protein was significantly induced by treatment with TNF-alpha in both eutopic endometrial stromal cells of women with and without endometriosis (p < 0.05), but the degree of induction was significantly increased in eutopic endometrial stromal cells of women with endometriosis than those of women without endometriosis (p < 0.05).

CONCLUSION

Overexpression of COX-2 by TNF-alpha in the eutopic endometrium of women with endometriosis may play a critical role in such pathophysiologic processes as endometriosis formation.

The expression and function of IGFBP-3 in normal and malignant breast tissue

The mitogenic and anti-apoptotic effects of insulin-like growth factor-I (IGF-I) are regulated by a family of insulin-like growth factor binding proteins (IGFBPs), particularly IGFBP-3. Little is known about the IGF-independent role of IGFBP-3 in breast cancer and the mechanisms regulating its production. The expression of IGFBP-3 in paired malignant and adjacent normal (n=53), and healthy normal (n=17) breast tissue samples was investigated using RT-PCR, immunohistochemistry and ELISA. We compared IGFBP-3 expression with other members of the IGF-I axis, other known tumorigenic genes and clinicopathological parameters. We also developed a novel tissue explant system using fresh normal and malignant breast tissue, with which we examined the in vitro effects of IGFBP-3 alone and in combination with known apoptotic agent, doxorubicin (n=6), on tissue viability and apoptosis. We demonstrated a high level of expression of IGFBP-3 mRNA in all samples. 96% of samples also expressed IGFBP-3 protein. No significant correlation was seen between IGFBP-3 expression and other clinicopathological parameters. The in vitro tissue explant system demonstrated that IGFBP-3 had little effect by itself on apoptosis. However, when used in combination with doxorubicin, increased apoptosis was seen in tumours. In contrast, less apoptosis was seen in normal tissue suggesting a protective effect. These divergent effects suggest a potential novel chemotherapeutic approach in the treatment of breast cancer. These findings suggest that IGFBP-3 may play a role in tumorigenesis, and that IGFBP-3 levels could be used in the future in cancer risk assessment/prevention or as markers of response to cancer treatments.

Cyclin-mediated G1 arrest by celecoxib differs in low-versus high-grade bladder cancer

BACKGROUND

Celecoxib and other non-steroidal anti-inflammatory drugs (NSAIDs) are being evaluated in the prevention of bladder and other cancers. Here we investigate molecular effects of celecoxib independent of cyclooxygenase (COX)-2 expression levels in urothelial carcinoma of the bladder.

MATERIALS AND METHODS

Low-grade RT-4 and high-grade UM-UC-3 bladder cancer cells were treated with 0-50 muM celecoxib. Growth, cell cycle and apoptosis were measured by crystal violet elution and flow cytometry. Western analysis was performed for COX-2, Rb, cyclin B1/D1, and phospho-cyclin B1/D1. COX-2 induction was achieved with phorbol ester.

RESULTS

Celecoxib inhibited growth of RT-4 and UM-UC-3, with G(1) cell cycle arrest and altered cyclin B1/D1 expression in RT-4, whereas Rb up-regulation occurred in UM-UC-3. Apoptosis occurred in both cell lines.

CONCLUSION

Celecoxib induces G(1) cell cycle arrest in low- and high-grade bladder cancer by different pathways. This heterogeneous molecular response supports combination approaches to prevention and treatment.

Involvement of cyclooxygenase 2 and prostagladin E(2) in the effects of insulin on gastric emptying in male rats

Delayed gastric emptying in patients with both type 1 and type 2 diabetes mellitus (DM) occurs in approximately 50% of these patients. However, the role and the action mechanism of insulin on gastrointestinal (GI) motility are still unclear. The purpose of the present study was to investigate the involvement of cyclooxygenase-2 (COX-2) and prostaglandin E(2) in the effects of insulin on gastric emptying in male rats. The normal and streptozotocin (STZ)-pretreated rats were injected intraperitoneally with or without insulin, atropine and specific muscarinic receptor antagonists before examination of measurement of gastric emptying, spontaneous contractile activity of smooth muscle strips, plasma cholecystokinin (CCK), and prostaglandin E(2) (PGE(2)) analysis. Protein expression of COX-2 and insulin receptors (IRs) were analyzed by the technique of western blot. Acute different doses of insulin accelerated gastric emptying. Atropine interrupted the insulin effect on gastric emptying, and muscarnic M1/M3 receptor antagonists interrupted the insulin-reversed gastric emptying in normal and DM rats. Besides, we observed the expression of (IRs) in GI and found that IR was changed under the insulin and DM treatment, and was also different between STZ-pretreated rats and hyperglycemic rats. Expression of COX-2 in stomach was decreased in DM rats but restored by insulin. The COX inhibitor, indomethacin, decreased the gastric emptying which was induced or reversed by insulin in normal and DM rats, respectively. PGE(2) production in stomach corresponded to the COX-2 expression. The contraction of GI smooth muscle stimulated by PGE(2) was increased in insulin-pretreated normal and DM rats. We conclude that insulin changed the expression of IRs in stomach in DM rats. The delayed GI motility in diabetes was at least in part due to the COX-2 and PGE(2) pathway which associated with decreasing COX-2 and diminishing PGE(2) production in stomach. The attenuation of PGE(2) production was employed for the index of the reduction of smooth muscle contraction in stomach in diabetes. Insulin stimulated the smooth muscle contraction through the IRs and COX-2 expression plus PGE(2) production in rat stomach as well as reversed the delayed gastric emptying via the nervous actions of muscarinic M1 and M3 receptors in DM rats.

Effect of mineral trioxide aggregate on rat clonal dental pulp cells: expression of cyclooxygenase-2 mRNA and inflammation-related protein via nuclear factor kappa B signaling system

INTRODUCTION

Recently, mineral trioxide aggregate (MTA) has been routinely used for endodontic treatment. It is well-known that MTA induced secondary dentin formation in pulp cavity when it was applied to dentin, whereas its cytotoxicities were unclear. The purpose of this study was to evaluate the effect of MTA on rat clonal dental pulp cells, RPC-C2A.

METHODS

This study was conducted to observe the response of RPC-C2A cells on MTA with reverse-transcriptase polymerase chain reaction, Western blot analysis, and enzyme immunoassay. Data were compared by analysis of variance. Statistical significance was established at P <.01.

RESULTS

MTA significantly caused an up-regulation of cyclooxygenase-2 (COX-2) and inducible form of nitric oxide synthase (iNOS) mRNA expression. Furthermore, MTA caused inhibitory kappa B (IkappaB) phosphorylation and translocation of nuclear factor-kappa B (NF-kappaB) subunits to nucleus. Curucumin, an inhibitor of NF-kappaB activation, suppressed MTA-induced COX-2 and iNOS mRNA expressions. In addition, MTA increased the production of prostaglandin E(2) in comparison with the controls.

CONCLUSIONS

MTA induces inflammation via NF-kappaB signaling system.

Anti-inflammatory effect of Streblus asper leaf extract in rats and its modulation on inflammation-associated genes expression in RAW 264.7 macrophage cells

AIM OF THIS STUDY

Streblus asper is a medicinal plant from Thailand used in folk medicine for the treatment of several inflammatory diseases. In this study, we investigated the anti-inflammatory effect of Streblus asper leaf ethanolic extract (SAE).

MATERIALS AND METHODS

The experimental carrageenan-induced paw edema in rats was performed in which the SAE at doses of 125, 250, 500 mg/kg body weight was intraperitoneally administered to the rats. Then, reverse transcriptive polymerase chain reaction (RT-PCR) technique was also performed to determine the effect of SAE on the expression of inflammation-associated genes in RAW 264.7 macrophage cells stimulated with lipopolysaccharide (LPS).

RESULTS

The SAE at all given doses caused a significant dose-dependent inhibition of edema (p<0.05). Moreover, the significant and dose-dependent LPS-induced cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) mRNA expressions were demonstrated in RAW 264.7 cells treated with SAE. The inhibition is selective, since COX-1 mRNA expression did not change in the presence of SAE.

CONCLUSION

The results of this study are the first scientific evidence on the molecular effects of Streblus asper as a potential anti-inflammatory agent, which supports the fact that the plant is employed in traditional remedies.

CD47 regulates collagen I-induced cyclooxygenase-2 expression and intestinal epithelial cell migration

Increased epithelial cell expression of the cyclooxgenase-2 (COX-2) enzyme is a characteristic event of both inflammatory bowel disease and colon cancer. We here report the novel findings that collagen I-induced de novo synthesis of COX-2 in intestinal epithelial cells is inhibited by pertussis toxin (PTX) and by an inhibitory peptide selective for the heterotrimeric Gα_i3-protein. These findings could be explained by a regulatory involvement of the G-protein-dependent integrin-associated protein CD47. In support of this notion, we observed a collagen I-induced association between CD47 and α2 integrins. This association was reduced by a blocking anti-CD47 antibody but not by PTX or a control anti-β2 antibody. Furthermore, a blocking antibody against CD47, dominant negative CD47 or specific siRNA knock down of CD47, significantly reduced collagen I-induced COX-2 expression. COX-2 has previously been shown to regulate intestinal epithelial cell adhesion and migration. Morphological analysis of intestinal cells adhering to collagen I revealed a co-localisation of CD47 and α2 integrins to non-apoptotic membrane blebs enriched in Rho A and F-actin. The blocking CD47 antibody, PTX and a selective COX-2 inhibitor, dramatically inhibited the formation of these blebs. In accordance, migration of these cells on a collagen I-coated surface or through a collagen I gel were significantly reduced by the CD47 blocking antibody, siRNA knock down of CD47 and the COX-2 inhibitor NS-398. In conclusion, we present novel data that identifies the G-protein-dependent CD47 protein as a key regulator of collagen I-induced COX-2 expression and a promoter of intestinal epithelial cell migration.

Cyclo-oxygenase-2 mediates hyperbaric oxygen preconditioning-induced neuroprotection in the mouse model of surgical brain injury

BACKGROUND AND PURPOSE

We investigated the role of cyclo-oxygenase-2 (COX-2) in mechanisms of hyperbaric oxygen preconditioning (HBO-PC) in the mouse model of surgical brain injury (SBI).

METHODS

C57BL mice were administered 100% oxygen for 1 hour at 2.5 atmosphere absolute for 5 consecutive days and subjected to SBI. Neurological status and brain edema were evaluated at 24 hours and 72 hours after the brain insult. Fluorescent immunostaining and Western blotting were performed to study hypoxia-inducible factor-1alpha and COX-2, respectively. Two doses of COX-2 inhibitor, NS398 (3 mg/kg and 10 mg/kg) were used to verify the role of COX-2 signaling pathway in the mechanism of HBO-PC.

RESULTS

HBO-PC improved neurological status and decreased brain edema at 24 hours and 72 hours after SBI. HBO-PC by itself and SBI independently increased COX-2 levels by 2-fold and 4-fold, respectively. HBO-PC, however, reduced increase in hypoxia-inducible factor-1alpha and COX-2 expression after SBI. The HBO-PC-induced improvement in neurological status and brain edema was reversed by a suboptimal dose of the COX-2 inhibitor, NS398 (10 mg/kg intraperitoneally; 1/4th of dose shown to provide neuroprotection), which itself had no effect on investigated end points.

CONCLUSIONS

HBO-PC attenuates postoperative brain edema and improves neurological outcomes after SBI. The HBO-PC-induced neuroprotection is mediated through COX-2 signaling pathways.

Cardiospermum halicacabum ethanol extract inhibits LPS induced COX-2, TNF-alpha and iNOS expression, which is mediated by NF-kappaB regulation, in RAW264.7 cells

AIM OF THIS STUDY

Cardiospermum halicacabum L. is well known for its anti-inflammatory, analgesic and antipyretic activities. It has been used in Ayurveda and folk medicine for the treatment of rheumatism, fever and earache. But its mechanism of anti-inflammatory and analgesic action is still unclear, hence in this context, the objective of our study is to reveal the mechanism of anti-inflammatory and analgesic activity of Cardiospermum halicacabum L. which would form an additional proof to the traditional knowledge of Cardiospermum halicacabum L.

MATERIALS AND METHODS

In this study the ethanolic extract of the whole plant was used to evaluate the anti-inflammatory action in mouse macrophage cell line RAW264.7 cells. The expression levels of cyclooxygenase (COX)-1, COX-2, tumor necrosis factor-alpha (TNF-alpha), inducible nitric oxide synthase (iNOS) and COX-2 protein expression by semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and western blot and nuclear factor kappa-B (NF-kappaB) binding activity by electrophoretic mobility shift assay (EMSA).

RESULTS

We found that the ethanol extract dose dependently inhibit mRNA expression of COX-2, TNF-alpha, iNOS and COX-2 protein expression. But the extract did not affect the expression of COX-1 mRNA expression. Furthermore, Cardiospermum halicacabum L. ethanol extract inhibited the TNF-alpha induced DNA binding activity of NF-kappaB, which was associated with decreased p65 protein level in the nucleus in Jurkat cells.

CONCLUSION

These results enabled to understand the mechanisms behind the anti-inflammatory and analgesic activity of Cardiospermum halicacabum L.

Nitro-aspirin inhibits MCF-7 breast cancer cell growth: effects on COX-2 expression and Wnt/beta-catenin/TCF-4 signaling

There is current evidence implicating the Wnt/beta-catenin/TCF pathway in breast cancer. We investigated the effect of para- and meta-positional isomers of nitric oxide-releasing aspirin (NO-ASA), and aspirin (ASA) on MCF-7 human breast cancer cell growth and beta-catenin/TCF signaling. The p- and m-NO-ASA isomers strongly inhibited cell growth and beta-catenin/TCF transcriptional activity compared to ASA; the IC50s for growth inhibition were 57+/-4, 193+/-10 and >5000microM, and for transcriptional inhibition they were 12+/-1.8, 75+/-6.5 and >5000microM for p-, m-NO-ASA and ASA, respectively. p-NO-ASA reduced the expression of Wnt/beta-catenin downstream target gene cyclin D1, and total cellular beta-catenin levels. COX-2 expression was induced by p-NO-ASA, protein kinase C inhibitors reversed this induction. p-NO-ASA blocked the cell cycle transition at S to G2/M phase. These studies suggest a targeted chemopreventive/chemotherapeutic potential for NO-ASA against breast cancer.

Expression of pro-inflammatory protein, iNOS, VEGF and COX-2 in oral squamous cell carcinoma (OSCC), relationship with angiogenesis and their clinico-pathological correlation

One main etiology for oral squamous cell carcinoma (OSCC) is inflammation. Inducible nitric oxide synthase (iNOS), vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2) are the important molecules showing close relation to not only inflammation but also carcinogenesis and angiogenesis. Angiogenesis is defined as the formation of new blood vessels from existing vasculature. It is necessary for tumor growth and progression and also involved in metastasis. The objective of this research was to study the expression and relationship among iNOS, VEGF, COX-2, angiogenesis and their clinico-pathological correlation in OSCC. In this study, standard indirect immunohistochemical technique using polyclonal antibodies specific to human iNOS, VEGF, COX-2 and CD31 was performed in formalin-fixed paraffin-embedded tissue sections of 66 OSCC samples. The staining patterns and intensity are measured and analyzed statistically. The results showed that epithelial components of squamous cell carcinomas demonstrated moderate to intense staining for iNOS, VEGF and COX-2. iNOS shows correlation with cervical lymph node metastasis and tumor staging (TNM) of the patients and angiogenesis. VEGF shows correlation with tumor grading, tumor staging and angiogenesis. COX-2 shows correlation with cervical lymph node metastasis. In conclusion, the expression of iNOS, VEGF and COX-2 exists in OSCC. The data provided show the expression of these chemical mediators associated with carcinogenesis and angiogenesis in OSCC. It can be the primary database before using angiogenesis drug against these mediators for OSCC treatment.

Angiotensin II-induced cyclooxygenase 2 expression in rat aorta vascular smooth muscle cells does not require heterotrimeric G protein activation

Angiotensin II (AngII) initiates cellular effects via its G protein-coupled angiotensin 1 (AT(1)) receptor (AT(1)R). Previously, we showed that AngII-induced expression of the prostanoid-producing enzyme cyclooxygenase 2 (COX-2) was dependent upon nuclear trafficking of activated AT(1)R. In the present study, mastoparan (an activator of G proteins), suramin (an inhibitor of G proteins), 1-[6-[[17beta-methoxyestra-1,3,5(10)-trien-17-yl]amino]hexyl]-1H-pyrrole-2,5-dione (U73122; a specific inhibitor of phospholipase C), and sarcosine(1)-Ile(4)-Ile(8)-AngII (SII-AngII; a G protein-independent AT(1)R agonist) were used to determine the involvement of G proteins and AT(1A)R trafficking in AngII-stimulated COX-2 protein expression in human embryonic kidney-293 cells stably expressing AT(1A)/green fluorescent protein receptors and cultured vascular smooth muscle cells, respectively. Mastoparan alone stimulated release of intracellular calcium and increased COX-2 expression. Preincubation with mastoparan inhibited AngII-induced calcium signaling without altering AngII-induced AT(1A)R trafficking, p42/44 extracellular signal-regulated kinase (ERK) activation, or COX-2 expression. Suramin or U73122 had no significant effect on their own; they did not inhibit AngII-induced AT(1A)R trafficking, p42/44 ERK activation, or COX-2 expression; but they did inhibit AngII-induced calcium responses. SII-AngII stimulated AT(1A)R trafficking and increased COX-2 protein expression without activating intracellular calcium release. These data suggest that G protein activation results in increased COX-2 protein expression, but AngII-induced COX-2 expression seems to occur independently of G protein activation.

Prognostic significance of tumor iNOS and COX-2 in stage III malignant cutaneous melanoma

PURPOSE

New prognostic markers are needed for malignant melanoma. Inducible nitric oxide synthase (iNOS) and cyclooxygenase type 2 (COX-2) have been described to correlate with progression of melanoma. Moreover, activating mutations in BRAF/NRAS oncogenes are often detected in melanoma. The BRAF/NRAS mutation status and expression of COX-2 and iNOS were examined to compare their prognostic value for overall survival (OS) in stage III malignant cutaneous melanoma.

EXPERIMENTAL DESIGN

The expression of iNOS and COX-2 in metastatic lymph nodes from 21 rapidly progressing (OS from date of diagnosis of stage III disease < or =14 months) and 17 slowly progressing (OS > or =60 months) stage III cutaneous melanoma patients was examined by immunohistochemistry. The presence of BRAF/NRAS mutations was analyzed using direct DNA sequencing. Chi2 exact trend test and logistic regression analysis were used for statistical analysis.

RESULTS

Both iNOS (P = 0.002) and COX-2 (P = 0.048) alone significantly predicted OS. The BRAF/NRAS mutation status did not significantly differ between patient groups, although iNOS significantly (P = 0.013) correlated with BRAF mutation frequency. Furthermore, the odds ratio (OR) with respect to OS of iNOS (OR = 10.4) was higher than that of COX-2 (OR = 5.6) and was stable in the multivariate analysis of OS together with disease stage IIIB/C, ulceration, number of metastatic lymph nodes, and Breslow tumor thickness.

CONCLUSION

Our data show that iNOS is an independent and stronger prognostic factor for OS in stage III malignant cutaneous melanoma than COX-2.

Imaging cyclooxygenase-2 (Cox-2) gene expression in living animals with a luciferase knock-in reporter gene

The cyclooxygenase-2 (Cox-2) gene plays a role in a variety of normal and pathophysiological conditions. Expression of the Cox-2 gene is induced in a broad range of cells, in response to many distinct stimuli. The ability to monitor and quantify Cox-2 expression noninvasively in vivo may facilitate a better understanding of the role of Cox-2, both in normal physiology and in different diseases. We generated a "knock-in" mouse in which the firefly luciferase reporter enzyme is expressed at the start site of translation of the endogenous Cox-2 gene. Correlation of luciferase and Cox-2 expression was confirmed in heterozygous Cox-2luc/+ mouse embryonic fibroblasts isolated from the knock-in mouse. In an acute sepsis model, following injection of interferon gamma and endotoxin, ex vivo imaging and Western blotting demonstrated coordinate Cox-2 and luciferase induction in multiple organs. Using both paw and air pouch inflammation models, we can monitor repeatedly localized luciferase expression in the same living mouse. Cox-2luc/+ knock-in mice should provide a valuable tool to analyze Cox-2 expression in many disease models.

Ghrelin ameliorates colonic inflammation. Role of nitric oxide and sensory nerves

Ghrelin is a novel growth hormone (GH)-releasing and orexigenic peptide with anti-inflammatory activities. However, the role of ghrelin in the colonic inflammation is still controversial. The aim of the present study was: 1) to examine the expression of ghrelin and TNF-alpha mRNA in the inflamed colonic mucosa of patients with ulcerative colitis (UC), 2) to analyze the effect of treatment with exogenous ghrelin on the healing of trinitrobenze sulphonic acid (TNBS)-induced colitis in rats, and 3) to assess the effects of ghrelin treatment on mRNA expression for iNOS and protein expression for COX-2 and PPARalpha in intact colonic mucosa and in that with TNBS-induced colitis. Fifteen patients with UC and fifteen healthy controls were enrolled in this study. Expression of ghrelin and TNF-alpha was assessed by semi-quantitative RT-PCR in the colonic mucosal biopsies from UC patients and healthy controls. In addition, the effect of exogenous ghrelin on healing of TNBS colitis was tested in rats without or with capsaicin-induced functional ablation of sensory nerves. Patients with UC showed a significant upregulation of mRNA for ghrelin and TNF-alpha in colonic mucosa as compared to that observed in healthy controls. The expression of ghrelin correlated with the grade of inflammation and expression of TNF-alpha. In rats the exogenous ghrelin administered daily at a dose of 20 microg/kg i.p. significantly accelerated the healing of TNBS colitis and this effect was accompanied by an increase in mRNA expression for iNOS and protein expression for COX-2 in the colonic mucosa. The protein expression for PPARgamma, which was down-regulated in rat colonic mucosa after exposure to TNBS as compared to that in intact colonic mucosa, was not significantly influenced by ghrelin treatment. We conclude that 1) patients with UC show an increased mucosal expression of mRNA for ghrelin in the colonic mucosa which could trigger protective response in inflamed colon; and 2) exogenous ghrelin accelerates healing of colonic lesions in animal model of ulcerative colitis via increased release of NO and PGE(2) due to an increase in iNOS and COX-2 expression and stimulation of sensory neuropeptides such as CGRP released from sensory afferent endings.

Cyclooxygenase-2 in mucosal DC mediates induction of regulatory T cells in the intestine through suppression of IL-4

Oral intake of protein leads to tolerance through the induction of regulatory T cells (Tr cells) in mesenteric lymph nodes (MLNs). Here we show that the inhibition of cyclooxygenase-2 (COX-2) in vivo suppressed oral tolerance and was associated with enhanced differentiation of interleukin (IL)-4-producing T cells and reduced Foxp3(+) Tr-cell differentiation in MLN. As a result, the functional suppressive capacity of these differentiated mucosal T cells was lost. IL-4 was causally related to loss of tolerance as treatment of mice with anti-IL-4 antibodies during COX-2 inhibition restored tolerance. Dendritic cells (DCs) in the MLN differentially expressed COX-2 and reductionist experiments revealed that selective inhibition of the enzyme in these cells inhibited Foxp3(+) Tr-cell differentiation in vitro. Importantly, the inhibition of COX-2 in MLN-DC caused increased GATA-3 expression and enhanced IL-4 release by T cells, which was directly related to impaired Tr-cell differentiation. These data provide crucial insights into the mechanisms driving de novo Tr-cell induction and tolerance in the intestine.

Expression of NF-kappaB and COX-2 in young versus older patients with sporadic colorectal cancer

AIM

To distinguish the expression of NF-kappaB and COX-2 between young and older group of sporadic colorectal cancer patients.

METHODS

This was a comparative study between sporadic CRC patients aged 40 years or younger and patients aged 60 years or more. Expression of NF-kappaB and COX-2 were assessed by immunohistochemical method using rabbit polyclonal antibodies against human p65 NF-kappaB and COX-2 proteins.

RESULTS

There were 98 cases of sporadic colorectal cancers between 1999 and 2007 obtained from the Department of Anatomical Pathology, Faculty of Medicine University of Indonesia, Jakarta and Department of Anatomical Pathology, Faculty of Medicine Padjajaran University, Bandung. There were 60 patients aged 60 years or more and 38 patients aged 40 years or less. Most tumors were located in the distal colon. Positive expression of NF-kappaB was found in 72 (73.5%) cases, whereas COX-2 expression was found in 48 (49.0%) cases. No significant difference of NF-kappaB and COX-2 expression between young and older patients.

CONCLUSION

The expression of nuclear factor kappaB (NF-kappaB) in Indonesian patients with sporadic colorectal cancer was high. However, cyclooxygenase-2 (COX-2) was only expressed in half of patients. There was no significant difference of NF-kappaB and COX-2 expressions between patients aged 40 years or less and patients aged 60 years or more. Further studies are needed to elaborate the role of inflammation in sporadic colorectal carcinogenesis.

[Expression of IGF-IR and COX-2 in renal cell carcinoma and their relationship with cell proliferation]

AIM

To investigate the expression of IGF-IR and COX-2 in renal cell carcinoma(RCC). To explore the correlation among IGF-IR, COX-2 and PCNA expression.

METHODS

Immunohistochemical staining was performed to detect the expression of IGF-IR, COX-2 and PCNA in 64 cases of RCC.

RESULTS

The positive rates of IGF-IR expression and COX-2 expression were 60.9%(39/64) and 51.6%(33/64) in RCC respectively. The expressions of IGF-IR and COX-2 in RCC tissues were not related to the histological type of RCC (P>0.05), but they were related to and increased with the size and clinical stages of RCC (P<0.05). The expression of IGF-IR was related to pathological grades, but COX-2 was not. The expression of IGF-IR was positively related with the expression of COX-2 and PCNA respectively, but there was negative correlation between COX-2 and PCNA.

CONCLUSION

The experiment suggests that IGF-IR and COX-2 may produce a synergetic effect in oncogenesis and progression of RCC. Detection of these genes has positive effects on early diagnosis, malignancy determination, prognosis and treatment of RCC.

Hydroxytyrosol inhibits pro-inflammatory cytokines, iNOS, and COX-2 expression in human monocytic cells

Hydroxytyrosol (HT), isolated from extra-virgin olive oil, possesses a marked antioxidant activity and is a good radical scavenger. In this study, our aim was to examine the anti-inflammatory mechanism of HT through measuring the inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) expression, TNF-alpha formation, and nitric oxide (NO) release in lipopolysaccharide (LPS)-induced human monocytic (THP-1) cells. Results showed that HT remarkably suppressed the LPS (1 microg/ml) induction of NO release. It also significantly attenuated the LPS-induced transcription of TNF-alpha, iNOS, and COX-2 in a dose-dependent manner. Furthermore, it was also found that HT in a concentration-dependent manner inhibited the expression of iNOS and COX-2 in THP-1 cells treated with 1 microg/ml LPS using Western Blot. Taken together, these results suggest that HT exerts anti-inflammatory effects probably through the suppression of COX-2 and iNOS expression.

Elevated plasma prostaglandins and acetylated histone in monocytes in Type 1 diabetes patients

AIMS/HYPOTHESIS

Inflammation is implicated in diabetes and cyclooxygenase (COX) is involved in vascular inflammatory processes, participating in both atherosclerosis and thrombosis. The aims were to determine whether levels of monocyte COX and plasma COX metabolites are increased in Type 1 diabetic patients and to determine whether these could be linked to histone hyperacetylation.

MATERIALS AND METHODS

Monocytes from 19 Type 1 diabetic and 39 non-diabetic control subjects were probed for COX and acetylated histone H4 proteins by immunoblotting. Plasma COX metabolite levels [thromboxane B(2) (TXB(2)) and prostaglandin E(2) (PGE(2))] were determined by enzyme immunoassay.

RESULTS

Monocyte COX-2 expression was significantly up-regulated (1.3-fold) in diabetic relative to the non-diabetic control subjects and plasma PGE(2) was markedly elevated (2.7-fold). In diabetic subjects, monocyte acetylated histone H4 levels were significantly elevated; sub-group analysis indicated that the increased histone acetylation was found only in the complication-free group.

CONCLUSIONS

Results support increased inflammatory activity in Type 1 diabetes that involves COX-2 and increased prostaglandin production, which may predispose patients to cardiovascular events. The observation of elevated histone acetylation only in complication-free diabetic subjects suggests that this may be a protective mechanism. This merits further investigation as histone hyperacetylation has been associated with reduced expression of factors involved in vascular injury and remodelling.

S1P/S1P2 signaling induces cyclooxygenase-2 expression in Wilms tumor

PURPOSE

Cyclooxygenase-2 has been reported to be ubiquitously expressed in Wilms tumor, the most common malignant renal tumor in children. However, to our knowledge the regulation mechanism of cyclooxygenase-2 expression remains unexplored.

MATERIALS AND METHODS

Quantitative real-time polymerase chain reaction and Western blot were performed to detect cyclooxygenase-2 mRNA and protein expression in WiT49 cells upon stimulation by S1P (Biomol(R)), and S1P(2) and cyclooxygenase-2 mRNA expression in 10 freshly frozen Wilms tumor tissues and matched normal tissues. Over expression, blockade and down-regulation of S1P(2) were determined using adenoviral transduction, the S1P(2) antagonist JTE-013 (Tocris Bioscience, Ellisville, Missouri) and small interfering RNA (Dharmacon, Lafayette, Colorado) transfection, respectively. The prostaglandin E(2) level in WiT49 cells was determined by gas chromatography/mass spectrometry.

RESULTS

S1P induced cyclooxygenase-2 mRNA and protein expression in WiT49 cells in a concentration dependent manner. Over expression of S1P(2) in WiT49 cells led to a significant increase in cyclooxygenase-2 mRNA and protein expression as well as subsequent prostaglandin E(2) synthesis. In addition, pretreatment of those cells that over expressed S1P(2) with the S1P(2) selective antagonist JTE-013 completely blocked S1P induced cyclooxygenase-2 protein expression. In accordance with these results silencing S1P(2) in WiT49 cells down-regulated S1P induced cyclooxygenase-2 expression. Further research in 10 Wilms tumor specimens showed that S1P(2) mRNA is greatly increased in Wilms tumor.

CONCLUSIONS

S1P induced cyclooxygenase-2 expression in Wilms tumor and this effect was mediated by S1P(2). This finding extends the biological function of S1P(2) and provides the biochemical basis for developing inhibitors targeting the S1P/cyclooxygenase-2 signaling pathway.

[The role of E2 and F2alpha prostaglandins in development of erosive-ulcerative lesions of the gastroduodenal region]

THE PURPOSE OF THE STUDY

To study role of E2 and F2alpha prostaglandins in development of erosive-ulcerative lesions of gastrointestinal tract.

MATERIALS AND METHODS

were examined patients with mucosal erosive-ulcerative and inflammatory lesions of gastrointestinal tract, as well as patients with osteoarthritis who received selective and non selective NSAIDs. Determination of E2 and F2alpha endogenous PG group was investigated with help of immunefuoration method with help of R&D Systems, Inc. Control group was 15 healthy patients.

RESULTS

in presented work you can find that there is relationship between degree of reduction of PG level and severity of gastrointestinal mucosal lesion area. The lowest values of PGE2 and PG F2alpha observed in patients with gastric ulcer disease, especially during exacerbation. Patients with low PG synthesis in body increases likelihood of gastropathy as to reception of non-selective COX inhibitors, and at receiving selective COX-2 inhibitors.

Resistance of cholangiocarcinoma cells to parthenolide-induced apoptosis by the excretory-secretory products of Clonorchis sinensis

Infection by Clonorchis sinensis, the Chinese or oriental liver fluke, is a significant risk factor for the development of cholangiocarcinoma, a human epithelial carcinoma of the intrahepatic bile duct. Parthenolide is a sesquiterpene lactone that has strong anticancer properties and is also known to induce apoptosis in cholangiocarcinoma cells. Many investigators have reported that excretory-secretory (ES) products of C. sinensis as well as Opisthorchis viverrini promote the development of cholangiocarcinomas. However, the intrinsic mechanism is not clearly understood. Therefore, we investigated the biological roles of the ES products in a cholangiocarcinoma cell line, HuCCT1. The ES products of C. sinensis increased proliferation of HuCCT1 cells and augmented the expression of cyclooxygenase (COX)-2. To determine whether cells treated with ES products would respond differently to parthenolide, HuCCT1 cells were treated with parthenolide alone or parthenolide after pretreatment with ES products. Cells pretreated with ES products were resistant to parthenolide-induced apoptosis. Because parthenolide has been reported to be a COX-2 inhibitor, we hypothesize that COX-2 might be a key factor that promotes resistance of cholangiocarcinoma cancer cells to parthenolide-induced apoptosis. These results suggest that chemotherapy treatment regimens in cholangiocarcinoma patients with C. sinensis infection should be modulated to account for ES products excreted by the liver fluke.

Aspisol inhibits tumor growth and induces apoptosis in breast cancer

Nonsteroidal anti-inflammatory drugs inhibit cell proliferation and induce apoptosis in various cancer cell lines, which is considered to be an important mechanism for their anti-tumor activity and cancer prevention. However, the molecular mechanisms through which these compounds induce apoptosis are not well understood.

AIM

to determine the effects of nonselective cyclooxygenase-2 (COX-2) inhibitor, aspisol on breast cancer cells in vitro and in vivo.

METHODS

The cytotoxic activity of aspisol was evaluated by MTT assay. The apoptosis index of cells was measured by flow cytometry. Immunohistochemical staining was used to detect expressions of COX-2 and caspase-3 in MDA-MB-231 cells. The expression of bcl-2 and bax was analyzed by Western blot analysis. The content of prostaglandin E2 (PGE2) in MDA-MB-231 cells was estimated by ELISA. In vivo apoptosis of the tumor cells was detected by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL).

RESULTS

Our results showed that aspisol reduced viability of MDA-MB-231 cells in time- and dose- dependent fashions and induced apoptosis by increase of caspase-3 and bax expressions while decrease of COX-2 and bcl-2 expression in vitro. In addition, exposure to aspisol decreased the basal release of PGE2. In vivo, aspisol also inhibited the proliferation of breast cancer cells and induced their apoptosis.

CONCLUSIONS

Our in vitro and in vivo data indicated that the antitumor effects of aspisol on breast cancer cells was probably mediated by the induction of apoptosis, and it could be linked to the downregulation of the COX-2 or bcl-2 expression and up-regulation of caspase-3 or bax expression.

Endothelin-1 stimulates cyclooxygenase-2 expression in ovarian cancer cells through multiple signaling pathways: evidence for involvement of transactivation of the epidermal growth factor receptor

Ovarian carcinoma cells release high amounts of endothelin-1 and exhibit increased expression of endothelin-A receptor. Engagement of the endothelin-A receptor triggers tumor growth, survival, neoangiogenesis and invasion. Cyclooxygenase-1 and cyclooxygenase-2 are enzymes involved in the production of prostaglandins and play a role in the regulation of tumor progression in several malignancies, including ovarian carcinomas. Endothelin-1 significantly increases the expression of cyclooxygenase-1 and cyclooxygenase-2 mRNA and protein, the activity of the cyclooxygenase- 2 promoter, and the release of prostaglandin E2 from two ovarian carcinoma cell lines, HEY and OVCA 433. The cyclooxygenase- 2 inhibitor, NS-398 drastically decreased the endothelin- 1-induced prostaglandin E2 production and vascular endothelial growth factor upregulation, indicating a role for cyclooxygenase-2 in endothelin-1-induced vascular endothelial growth factor-mediated angiogenesis. In this study we demonstrated that endothelin-1-induced cyclooxygenase-2 and related prostaglandin E2 release were dependent upon the activation of endothelin-A receptor and of multiple mitogen-activated protein kinase signal pathways, including extracellular signal-regulated kinase 1/2 kinase, p38 mitogen-activated protein kinase and the transactivation of the epidermal growth factor receptor. In human ovarian xenografts, the levels of cyclooxygenase-2 protein expression were significantly reduced following treatment with the endothelin-A receptor selective antagonist, atrasentan, compared with untreated mice. These results suggest that the pharmacological blocking of endothelin-A receptor is an attractive strategy to control the cyclooxygenase-2 protein expression in ovarian carcinoma.

Pioglitazone, a ligand for peroxisome proliferator-activated receptor-gamma acts as an inhibitor of colon cancer liver metastasis

BACKGROUND

Peroxisome proliferator-activated receptor-gamma (PPARgamma) is a member of the steroid receptor superfamily. Liganded PPARgamma can inhibit cancer cell proliferation. The in vitro and in vivo inhibitory effect of the synthetic ligands, ciglitazone (CGZ) and pioglitazone (PGZ), on human colon cancer was investigated.

MATERIALS AND METHODS

Cell proliferation and the expression of PPARgamma, cyclooxygenase (COX)-2 and cyclin D1 were assessed in colon cancer cells treated with CGZ or PGZ. After subcutaneous or splenic inoculation of severe combined immunodeficient (SCID) mice using colon cancer HT-29 and SW480 cells, PGZ was administered orally and tumor growth inhibition was assessed by xenograft volume. The COX-2, cyclin D1 and PPARgamma expression in the HT-29 cells was evaluated.

RESULTS

Cultured HT-29 and SW480 cells expressed PPARgamma and proliferation was inhibited by CGZ and PGZ. Oral PGZ inhibited xenograft tumor growth and liver metastases in the SCID mouse and suppressed expression of COX-2 and cyclin D1 in HT-29 cells.

CONCLUSION

PGZ down-regulates COX-2 and cyclin D1 and inhibits colon cancer proliferation and liver metastasis, making PPARgamma a candidate target for the treatment/prevention of colon cancer metastasis.

[Expressions of MMP-2 and COX-2 mRNA in bladder transitional cell carcinoma and their correlation]

OBJECTIVE

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

METHODS

We 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.

RESULTS

The 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).

CONCLUSION

MMP-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.

[Expression of cyclooxygenase-2 in bladder transitional cell carcinoma and the significance thereof]

OBJECTIVE

To study the expression of cyclooxygenase-2 (COX-2) in bladder transitional cell carcinoma (Tcc) and the clinical significance thereof.

METHODS

Immunohistochemistry was used to detect the expression of COX-2 in 56 specimens of bladder Tcc and 10 specimens of normal bladder tissue, all resected during operation.

RESULTS

No expression of COX-2 was detected in the 10 specimens of normal bladder tissue and in the 56 specimens of bladder Tcc the positive rate of COX-2 was 55.36%. The expression of COX-2 in bladder Tcc was closely correlated with the grade and stage of tumor (both P < 0.01).

CONCLUSION

COX-2 expression in bladder Tcc is closely correlated with the grade and stage.

Blood COX-2 and PGES gene transcription during the peripartum period of dairy cows with normal puerperium or with uterine infection

In the dairy cow, puerperal uterine intra-luminal concentrations of PGE(2) are related to the establishment and severity of uterine infections. Here we evaluated whether the blood concentrations of PGE(2) and the gene transcription profiles of enzymes involved in its synthesis (cyclooxygenase-2 and prostaglandin E synthase) could be used as markers of predisposition and/or presence of puerperal uterine infections. We also studied the relationship between the endocrine status and the leukocyte profiles around parturition and the transcription patterns of the genes. Finally, we have characterized the in vitro gene transcription and expression response to a challenge of LPS. Gene transcription profiles, quantified by real-time PCR, were similar in normal puerperium and metritis/endometritis cows, indicating that they are not suitable markers of predisposition to/presence of puerperal uterine infections. Transcription decreased from 2 weeks before parturition until parturition, when a minimum was attained, and then increased during the first week postpartum. The lowest gene transcription, at parturition, was coincidental with the highest total leukocytes, polymorphonuclear neutrophils and CD14 positive cell numbers. It is suggested that by this mechanism, a large number of PMN can be recruited into the uterus after parturition, avoiding an excessive acute inflammatory response. The lowest gene transcription was also coincidental with the surge in cortisol concentrations, indicating that this hormone plays a main immunomodulatory role around parturition. Gene transcription was significantly greater after stimulation with LPS than in non-stimulated blood. We suggest that this PGE(2) producing cells might arrive to the uterine lumen, contributing to the local PGE(2) concentrations and mediating the inflammatory response.

The role of fatty acids and caveolin-1 in tumor necrosis factor alpha-induced endothelial cell activation

Hypertriglyceridemia and associated high circulating free fatty acids are important risk factors for atherosclerosis. In contrast to omega-3 fatty acids, linoleic acid, the major omega-6 unsaturated fatty acid in the American diet, may be atherogenic by amplifying an endothelial inflammatory response. We hypothesize that omega-6 and omega-3 fatty acids can differentially modulate tumor necrosis factor alpha (TNF-alpha)-induced endothelial cell activation and that functional plasma membrane microdomains called caveolae are required for endothelial cell activation. Caveolae are particularly abundant in endothelial cells and play a major role in endothelial trafficking and the regulation of signaling pathways associated with the pathology of vascular diseases. To test our hypothesis, endothelial cells were preenriched with either linoleic acid or alpha-linolenic acid before TNF-alpha-induced endothelial activation. Measurements included oxidative stress and nuclear factor kappaB-dependent induction of cyclooxygenase-2 (COX-2) and prostaglandin E(2) (PGE(2)) under experimental conditions with intact caveolae and with cells in which caveolin-1 was silenced by small interfering RNA. Exposure to TNF-alpha induced oxidative stress and inflammatory mediators, such as p38 mitogen-activated protein kinase (MAPK), nuclear factor kappaB, COX-2, and PGE(2), which were all amplified by preenrichment with linoleic acid but blocked or reduced by alpha-linolenic acid. The p38 MAPK inhibitor SB203580 blocked TNF-alpha-mediated induction of COX-2 protein expression, suggesting a regulatory mechanism through p38 MAPK signaling. Image overlay demonstrated TNF-alpha-induced colocalization of TNF receptor type 1 with caveolin-1. Caveolin-1 was significantly induced by TNF-alpha, which was further amplified by linoleic acid and blocked by alpha-linolenic acid. Furthermore, silencing of the caveolin-1 gene completely blocked TNF-alpha-induced production of COX-2 and PGE(2) and significantly reduced the amplified response of linoleic acid plus TNF-alpha. These data suggest that omega-6 and omega-3 fatty acids can differentially modulate TNF-alpha-induced inflammatory stimuli and that caveolae and its fatty acid composition play a regulatory role during TNF-alpha-induced endothelial cell activation and inflammation.

7beta-Hydroxy-epiandrosterone-mediated regulation of the prostaglandin synthesis pathway in human peripheral blood monocytes

7alpha-Hydroxy-DHEA, 7beta-hydroxy-DHEA and 7beta-hydroxy-EpiA are native metabolites of dehydroepiandrosterone (DHEA) and epiandrosterone (EpiA). Since numerous steroids are reported to interfere with inflammatory and immune processes, our objective was to test the effects of these hydroxysteroids on prostaglandin (PG) production and related enzyme gene expression. Human peripheral blood monocytes were cultured for 4 and 24 h in the presence of each of the steroids (1-100 nM), with and without addition of TNF-alpha (10 ng/mL). Levels of PGE(2), PGD(2) and 15-deoxy-Delta(12,14)-PGJ(2) (15d-PGJ(2)) were measured in the incubation medium, and cell content of cyclooxygenase (COX-2), and PGE and PGD synthases (m-PGES1, H-PGDS, L-PGDS), and peroxisome proliferator activated receptor (PPAR-gamma) was assessed by quantitative RT-PCR and Western blots. Addition of TNF-alpha resulted in elevated PG production and increased COX-2 and m-PGES1 levels. Among the three steroids tested, only 7beta-hydroxy-EpiA decreased COX-2, m-PGES1 and PPAR-gamma expression while markedly decreasing PGE(2) and increasing 15d-PGJ(2) production. These results suggest that 7beta-hydroxy-EpiA is a native trigger of cellular protection through simultaneous activation of 15d-PGJ(2) and depression of PGE(2) synthesis, and that these effects may be mediated by activation of a putative receptor, specific for 7beta-hydroxy-EpiA.

Ethyl pyruvate has an anti-inflammatory effect by inhibiting ROS-dependent STAT signaling in activated microglia

Ethyl pyruvate (EP) has been demonstrated to have an anti-inflammatory function. However, the molecular mechanisms underlying the anti-inflammatory action of EP are largely unknown. We here show that EP exerts its anti-inflammatory effect by inhibiting ROS-dependent STAT signaling through its antioxidant activity, like vitamin C or N-acetyl-L-cysteine. The inhibition of STAT1 and STAT3 by EP prevented their translocation to the nucleus and consequently inhibited expression of iNOS and COX-2 by inhibiting STAT1- and STAT3-mediated transcriptional activity, followed by changes in chromatin conformation via deacetylation of histones H3 and H4 in both gene promoters. EP also suppressed transcripts of other STAT-responsive inflammatory genes such as IL-1beta, IL-6, TNF-alpha, and MCP-1. We further found that the mechanism of inhibition of STAT1 and STAT3 by EP is due to inhibition of JAK2 through Rac1 inactivation and SOCS1 induction. These findings offer new therapeutic possibilities for EP based on a better understanding of the mechanism underlying the action of EP.

Effect of losartan on cyclooxygenase-2 expression in normal human mesangial cells and kidneys of rats with diabetic nephropathy

OBJECTIVE

To investigate the effect of high glucose and losartan on cell proliferation and cyclooxygenase-2 (COX2) expression in normal human mesangial cells (NHMCs), and to examine the effect of losartan on COX2 and transforming growth factor-beta1 (TGF-beta1) expression in a model of diabetic nephropathy (DN).

METHODS

NHMCs were cultured in vitro in high glucose media with or without losartan. NHMCs proliferation and COX2 expression were determined by WST-1, Western blot, and RT-PCR. The rat model of DN was produced by injections of streptozocin (STZ). After the treatment with losartan for 4 weeks, glomerular hypertrophy, urinary thromboxane B2 (TXB2) and 24 h urinary protein counts were measured, and COX2 and TGF-beta1 expressions were investigated using immunohistochemical techniques and RT-PCR.

RESULTS

Losartan dose-dependently inhibited the proliferation of NHMCs in response to high glucose. Losartan also decreased COX2 expression in NHMCs at high or low glucose concentrations. In vivo experiments found kidney weight/body weight (KW/BW), urinary TXB2 and 24 h urinary protein counts increased significantly in the DN group. Losartan reduced KW/BW, urinary TXB2, and 24 h urinary protein counts and significantly suppressed the over-expression of COX2 and TGF-beta1.

CONCLUSION

Losartan reduces COX2 expression in NHMCs,especially at high glucose concentrations. Losartan could suppress the expression of COX2 and TGF-beta1 in the kidney of DN rats and attenuate the renal lesions caused by DN.

Positive correlation between cyclooxygenase 2 and the expression of ABC transporters in non-small cell lung cancer

BACKGROUND

The primary method of treatment of non-small cell lung cancer (NSCLC) in stage IIIB and IV is chemotherapy. Previous data suggested a correlation between cyclooxygenase-2 (COX-2) expression and the multidrug-resistant phenotype of cancer cells.

MATERIALS AND METHODS

In this prospective study, 32 patients with NSCLC in stage IIIB and IV from 1,078 patients were included. The expression of COX-2 as well as the expression of the ABC transporters MDR1/P-glycoprotein (MDR1/P-gp), BCRP and MRP1 were detected immunohistochemically.

RESULTS

Univariate and multivariate analyses demonstrated no prognostic or predictive significance of these proteins. It was merely demonstrated that complete or partial response are favourable factors for prediction of longer progression-free survival time. However, a strong positive correlation between the expression of COX-2, MDR1/P-gp and BCRP was found in NSCLC.

CONCLUSION

These data suggest no clinical impact for the expression of MDR1/P-gp, MRP1, BCRP or COX-2 in NSCLC, but a putative coregulation of COX-2 and MDRI/P-gp and BCRP in NSCLC.

Glucocorticoid-induced leucine zipper (GILZ) mediates glucocorticoid action and inhibits inflammatory cytokine-induced COX-2 expression

Cyclooxygenase-2 (COX-2) plays an important role in rheumatoid arthritis and therefore, has been a major target for anti-arthritis therapies. The expression of COX-2 is induced by inflammatory cytokines such as TNF-alpha and IL-1beta, and inhibited by glucocorticoids. However, the molecular mechanisms underlying the anti-inflammatory and immune suppressive actions of glucocorticoids are not well defined. Here we report that glucocorticoid-induced leucine zipper (GILZ) mimics glucocorticoid action and inhibits inflammatory cytokine-induced COX-2 expression in bone marrow mesenchymal stem cells, the cells that have been recently implicated in the pathogenesis and progression of rheumatoid arthritis. Using a retrovirus-mediated gene expression approach we demonstrate that overexpression of GILZ inhibits TNF-alpha and IL-1beta-induced COX-2 mRNA and protein expression, and knockdown of GILZ by shRNA reduces glucocorticoid inhibition of cytokine-induced COX-2 expression. Consistent to these results, overexpression of GILZ also inhibits NF-kappaB-mediated COX-2 promoter activity. Finally, we show that GILZ inhibits COX-2 expression by blocking NF-kappaB nuclear translocation. Our results suggest that GILZ is a key glucocorticoid effect mediator and that GILZ may have therapeutic value for novel anti-inflammation therapies.

[Ginsenoside Rg1 modulates COX-2 expression in the substantia nigra of mice with MPTP-induced Parkinson disease through the P38 signaling pathway]

OBJECTIVE

To investigate the role of P38 signaling pathway in modulating the expression of cyclooxygenase-2 (COX-2) in the substantia nigra (SN) of mice with 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced Parkinson disease (PD), and explore the possible mechanism of the dopaminergic (DA) neuron death in PD and the effects of ginsenoside Rg1 on the P38 signaling pathway and DA neurons.

METHODS

C57BL6 mice were treated with MPTP to produce the subacute PD model, and the behavioral changes were observed. Immunohistochemistry and Western blotting for tyrosine hydroxylase (TH), COX-2, prostaglandin E2 (PGE2) and phosphorylated P38 (p-P38) were used to observe the changes of positive cell number in the midbrain after treatment with ginsenoside Rg1.

RESULTS

Compared with the control mice, the mice with PD presented with typical symptoms of PD. The number of p-P38-, COX-2-, and PGE2-positive cells significantly increased in the SN area 6 h after the 3rd injection of 30 mg/kg MPTP (P<0.01). The number of TH-positive neurons in the PD model group was substantially reduced by about 60% (P<0.01) in 24 h after the 5th injection of MPTP. In mice with ginsenoside Rg1 treatment, the number of p-P38-, COX-2-, and PGE2-positive cells was reduced obviously 6 h after the 3rd injection of MPTP as compared with that in the model group (P<0.01). The number of TH-positive neurons in the SN was decreased by only 30% (P<0.01 vs control group) 24h after the 5th injection of MPTP.

CONCLUSION

P38 signaling pathway may play an important role in modulating COX-2 expression in the SN in the early stage of MPTP-induced subacute PD, and ginsenoside Rg1 may act on the P38 signaling pathway to protect the DA neurons in PD.

[Xiaojin Wan inhibits the expression of COX-2 in prostate tissues of prostatitis pain rats]

OBJECTIVE

To study the effect of Xiaojin Wan on the expression of COX-2 in the prostate tissues of rats with prostatitis pain, and the action mechanism of the drug alleviating the prostatitis pain.

METHODS

Sixty male Wistar rats were randomized into two groups, 10 as blank controls, injected with aqua pro injection into the ventral part of prostate, and the other 50 as prostatitis pain models, given complete Freund's adjuvant (CFA). Three days later, the pain model rats were again equally divided into 5 subgroups: model control, Celecoxib Capsules, high-, median- and low-dose Xiaojin Wan, receiving intragastric administration of distilled water, Celecoxib Capsules and different doses of Xiaojin Wan respectively for 4 weeks. Then they were killed, the harvested tissues fixed with 10% paraformaldehyde and the changes of the COX-2 expression in the prostate detected with the immunohistochemical technique and graphics video analysis system.

RESULTS

The expression of COX-2 was strong in the model group, significantly lower in the high- and median-dose and the Celecoxib Capsules groups than in the model control (P < 0.01) as well as in the high-dose than in the median- and low-dose groups (P < 0.01).

CONCLUSION

Xiaojin Wan may alleviate prostatitis pain by inhibiting the expression of COX-2 in prostate tissues.

Synergistic regulation of COX-2 expression by bombesin and transforming growth factor-beta

Overexpression of cyclooxygenase-2 (COX-2), an inducible enzyme regulating prostaglandin release, is mechanistically linked to the development, growth, and spread of gastrointestinal (GI) cancers. GI peptide bombesin (BBS) was reported to stimulate COX-2 gene expression. Here we show that TGF-beta1 dramatically enhances the BBS-induced expression of COX-2 mRNA and protein, and the release of PGE2 in the model rat intestinal epithelial cell (RIE-1) line. The synergistic increase in COX-2 levels results from a combination of enhanced COX-2 transcription and reduced mRNA degradation. BBS, but not TGF-beta1, stimulated COX-2 promoter activity, and TGF-beta1 enhanced COX-2 mRNA stability through a p38(MAPK)-dependent pathway. The synergistic regulation of COX-2 expression by TGF-beta1 and BBS may contribute to the upregulation of COX-2 in GI cancers.

Role of caveolin-1 in EGCG-mediated protection against linoleic-acid-induced endothelial cell activation

Flavonoids can protect against inflammatory diseases such as atherosclerosis by decreasing vascular endothelial cell activation. Plasma microdomains called caveolae may be critical in regulating endothelial activation. Caveolae are particularly abundant in endothelial cells and play a major role in endothelial trafficking and the regulation of signaling pathways associated with the pathology of vascular diseases. We hypothesize that flavonoids can down-regulate endothelial inflammatory parameters by modulating caveolae-regulated cell signaling. We focused on the role of caveolae and its major protein, caveolin-1, in mechanisms of linoleic-acid-induced endothelial cell activation and protection by the catechin epigallocatechin-3-gallate (EGCG). Exposure to linoleic acid for 6 h induced expression of both caveolin-1 and cyclooxygenase (COX)-2. Pretreatment with EGCG blocked fatty-acid-induced caveolin-1 and COX-2 expression in a time- and concentration-dependent manner. Similar results were observed with nuclear factor-kappa B DNA binding activity, which was also reduced by caveolin-1 silencing. Exposure to linoleic acid rapidly increased phosphorylation of several kinases, including p38 MAPK, extracellular signal regulated kinase 1/2 (ERK1/2) and amino kinase terminal (Akt), with maximal induction at about 10 min. Inhibitors of ERK1/2 and Akt down-regulated the linoleic-acid-induced increase in COX-2 protein, which also occurred after pretreatment with EGCG. Caveolin-1 silencing blocked linoleic-acid-induced phosphorylation of ERK1/2 and protein expression of COX-2, suggesting that specific MAPK signaling is caveolae dependent. Our data provide evidence that caveolae may play a critical role in regulating vascular endothelial cell activation and protection by flavonoids such as EGCG.

Expression of p63 and cyclooxygenase-2 and their correlation in skin tumors

To study the expression of p63 and cyclooxygenase-2 (cox-2) in skin tumors and evaluate the correlation between p63 and cox-2, the expressions of cox-2 and p63 were measured by streptavidin-peroxidase complex immunohistochemical technique in 17 cases of skin squamous cell carcinoma (SCC), 19 cases of Bowen's disease(Bowen), 11 cases of actinic keratosis(AK), 12 cases of seborreic keratosis(SK) and 13 specimens of normal skin. Our results showed that the expression of p63 in skin squamous cell carcinoma, Bowen's disease and actinic keratosis were significantly higher than that in seborreic keratosis, while the expression of p63 in seborreic keratosis was significantly higher than that in normal skin. The expression of cox-2 in skin squamous cell carcinoma, Bowen's disease and actinic keratosis were significantly higher than that in seborreic keratosis, while no statistical difference was noted in the expression of cox-2 between seborreic keratosis and normal skin. Cox-2 expression was positively correlated with the high p63 expression in malignant skin tumors. The increased expression of cox-2 and p63 may play an important role in the development of skin tumors and work synergetically in malignant skin tumors.

Microvessel density (MVD) and cyclooxygenase-2 (COX-2)/ beta-catenin interaction are associated with relapse in patients with transitional carcinoma receiving adjuvant chemotherapy with paclitaxel/carboplatin: a hellenic cooperative oncology group (HECOG) study

BACKGROUND

Cycloxygenase (COX)-2 has been associated with proliferation, apoptosis and angiogenesis in urothelial cancer. The prognostic significance of COX-2 in patients who received adjuvant chemotherapy for urothelial cancer was examined.

PATIENTS AND METHODS

Expression of COX-2, p53, ki67, beta-catenin, vascular endothelial growth factor (VEGF) and microvessel density (MVD) were studied retrospectively in 59 patients with urothelial cancer (pT3, pT4, N+) who had undergone surgery. The patients had subsequently received adjuvant chemotherapy.

RESULTS

Thirty-eight out of 59 cases (64%) were positive for COX-2. COX-2 was not associated either with progression-free survival (PFS) or overall survival (OS). MVD levels > or =47 were associated with longer median PFS compared with lower levels (not reached vs. 13 months [95% CI: 8-18], p=0.048). The median PFS for patients with beta-catenin nuclear accumulation and COX-2 expression was 6 months (95% CI: 4-7) compared with 19 months (95% CI: 14-23) for neither or only one of these factors (p=0.018).

CONCLUSION

MVD may be a useful indicator of relapse in high-risk urothelial cancer treated with adjuvant chemotherapy.

A PPAR-independent pathway to PUFA-induced COX-2 expression

Polyunsaturated fatty acids (PUFAs) induce COX-2 in bovine endometrial stromal cells through activation of peroxisome-proliferator-activated receptor alpha (PPARalpha). We have investigated alternative (PPAR-independent) pathways to COX-2 induction using a reporter construct driven by a COX-2 gene promoter sequence lacking a PPAR response element. This construct was induced by PUFAs, but not by PPAR agonists. PPAR-independent reporter gene expression occurred 6h after PPAR-dependent induction of the endogenous COX-2 gene. In contrast to PPAR-dependent COX-2 induction, which is not affected by NF-kappaB inhibitors, the PPAR-independent pathway was blocked by the NF-kappaB inhibitor MG132 or following deletion of NF-kappaB sites in the COX-2 promoter. The PPAR-independent effect of PUFA was mimicked by the PKC activators 4beta-PMA and prostaglandin F(2alpha), but was not blocked by the PKC inhibitor RO318425. The results demonstrate a pathway to the induction of COX-2 by PUFAs requiring NF-kappaB but not PPAR or PKC.

Genes controlling spread of breast cancer to lung "gang of 4"

Cancer-related mortality is caused in a large part by the metastasis of primary tumor. Each cancer has a particular way of spreading cancerous cells. Recently, genetic and pharmacological analysis identified the set of genes, such as epidermal growth factor receptor ligand epiregulin (EREG), cyclooxygenase-2 (COX2) and matrix metalloproteinases 1 and 2 (MMP-1 and MMP-2) that have been found to be associated with metastasis of breast cancer to lung. Inhibition of EGFR and COX2 could minimize lung metastasis of breast cancer in a clinical setting. In this review, we summarized the current knowledge on EREG, COX2, MMP-1 and MMP-2 in tumor development and metastasis.

A lipid-derived endogenous inducer of COX-2: a bridge between inflammation and oxidative stress

Several lines of evidence indicate that the oxidative modification of protein and the subsequent accumulation of the modified proteins have been found in cells during aging, oxidative stress, and in various pathological states including premature diseases, muscular dystrophy, rheumatoid arthritis, and atherosclerosis. The important agents that give rise to the modification of a protein may be represented by reactive aldehydic intermediates, such as ketoaldehydes, 2-alkenals and 4-hydroxy-2-alkenals. These reactive aldehydes are considered important mediators of cell damage due to their ability to covalently modify biomolecules, which can disrupt important cellular functions and can cause mutations. Furthermore, the adduction of aldehydes to apolipoprotein B in low-density lipoproteins (LDL) has been strongly implicated in the mechanism by which LDL is converted to an atherogenic form that is taken up by macrophages, leading to the formation of foam cells. During the search for an endogenous inducer of cyclooxygenase-2 (COX-2), an inducible isoform responsible for high levels of prostaglandin production during inflammation and immune responses, 4-hydroxy-2-noennal (HNE), one of the most representative lipid peroxidation product, has been identified as the potential inducer of COX-2. In addition, the following study on the molecular mechanism of the COX-2 induction by HNE has unequivocally established that a serum component, which is eventually identified to be denatured LDL, is essential for COX-2 induction. Here I review current understanding of the mechanisms by which HNE in cooperation with the serum component activates gene expression of COX-2.

Effects of San-Huang-Xie-Xin-Tang on U46619-induced increase in pulmonary arterial blood pressure

ETHNOPHARMACOLOGICAL RELEVANCE

San-Huang-Xie-Xin-Tang (SHXT), composed of Coptidis rhizoma, Scutellariae radix and Rhei rhizoma, is traditionally used to treat hypertension.

AIM OF THE STUDY

Our aim was to investigate the pharmacology effect of SHXT on a thromboxane A(2) analogue U46619-induced increase in pulmonary hypertension and protein expression in primary pulmonary smooth muscle cells (PASMCs).

MATERIALS AND METHODS

Arterial blood pressure and isometric tension in the aorta and pulmonary artery of rats were measured by pressure and force transducers, respectively. Protein expressions on PASMCs were detected by Western blotting.

RESULTS

SHXT significantly attenuated U46619-induced increase in arterial blood pressure. The inhibitory effect of SHXT on pulmonary arterial pressure was greater than systemic arterial pressure in U46619 treated rats. Similarly, the inhibitory effect of SHXT on U46619-induced vasoconstriction in rat pulmonary arterial rings was greater than that in aortic rings. In U46619 treated PASMCs, SHXT down-regulated expression of phosphodiesterase type 5 (PDE5), Rho-kinase (ROCK) II, cyclooxygenase-2 (COX-2) and up-regulated expression of soluble guanylyl cyclase (sGC) alpha(1) and sGCbeta(1).

CONCLUSIONS

SHXT attenuated U46619-induced increase in systemic and pulmonary arterial blood pressure. Inhibition of PDE5, ROCK-II, COX-2 and stimulation of sGC may play important roles in the cardiovascular effects of SHXT.

Differences in expression of tumor markers between pre- and postmenopausal women with invasive cervical cancer

THE AIM of the present study was to investigate the differences in the expression of tumor markers in squamous cell and in adenomatous carcinomas in pre- and postmenopausal women, respectively.

PATIENTS AND METHODS

The study population comprised 53 premenopausal and 107 postmenopausal women. Thirty-four tumors were adenomatous (n=31) or adenosquamous carcinomas (n=3), distributed between 13 premenopausal and 21 postmenopausal women. The remaining 126 squamous cell carcinomas were diagnosed in 40 pre- and 86 postmenopausal women. Expression of ten tumor markers of possible clinical importance in cervical cancer was evaluated.

RESULTS

Expression of three tumor markers, p53 (>0% vs. 0%), p27 (> or =20% vs. <20%) and cyclooxygenase-2 (COX-2) (high intensity vs. moderate/none) differed significantly between pre- compared to postmenopausal women with squamous cell (p27; 54% vs. 72%, p=0.009) or adenomatous carcinomas (p53; 8% vs. 63%, p=0.006 and COX-2; 46% vs. 20%, p=0.03). All results were adjusted for clinical cancer stage.

CONCLUSION

The unusual age-specific incidence curve in cervical cancer has rarely been related to expression of tumor markers. Age-related differences in expression of tumor markers could reflect some age-related different biological mechanisms in cervical cancer.

The effect of polysaccharide extracted from the marine alga Capsosiphon fulvescens on ethanol administration

Seaweed extracts have recently been found to have antioxidant and antitumor activities. Capsosiphon fulvescens (Cf) is a green alga and nutrient-dense food source. In a previous study, we extracted polysaccharide from Cf (Cf-PS) and demonstrated its antitumor effect in gastric cancer cells. In this report, we describe the protective effect of Cf-PS against alcohol-induced gastric injury in rats and adenocarcinoma (AGS) cells. In vivo assay revealed stomach damage in rats treated with alcohol alone; however, the stomach condition of rats co-treated with Cf-PS and alcohol matched that of the control group. Cf-PS also inhibited alcohol-induced cell death in AGS cells. Compared with alcohol treatment alone, Cf-PS and alcohol co-treatment increased phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt but inhibited poly-ADP-ribose polymerase (PARP) cleavage. Thus, ERK1/2 and Akt activation are instrumental in the protective effect of Cf-PS against alcohol-induced cell death in AGS cells. Moreover, Cf-PS treatment reduced the expressions of cyclooxygenase-2 (COX-2) and the inducible form of nitric oxide (iNOS), proteins related to ulcers. These results suggest that Cf-PS could help protect against alcohol-induced peptic ulcers.