Exploration of cyclooxygenase-2 inhibitory peptides from walnut dreg proteins based on in silico and in vitro analysis

Walnut dreg protein hydrolysates(WDPHs)exhibit a variety of biological activities,however,the cyclooxygenase-2(COX-2)inhibitory peptide of WDPHs remain unclear.The aim of this study was to rapidly screen for such peptides in WDPHs through a combination of in silico and in vitro analysis.In total,1262 peptide sequences were observed by nano liquid chromatography/tandem mass spectrometry(nano LC-MS/MS)and 4 novel COX-2 inhibitory peptides(AGFP,FPGA,LFPD,and VGFP)were identified.Enzyme kinetic data indicated that AGFP,FPGA,and LFPD displayed mixed-type COX-2 inhibition,whereas VGFP was a non-competitive inhibitor.This is mainly because the peptides form hydrogen bonds and hydrophobic interactions with residues in the COX-2 active site.These results demonstrate that computer analysis combined with in vitro evaluation allows for rapid screening of COX-2 inhibitory peptides in walnut protein dregs.

Lafoensia pacari alleviates intestinal damage by modulating cyclooxygenase-2:In silico and in vivo evaluation in a colitis model

BACKGROUND Inflammatory bowel diseases(IBD)are a worldwide health problem and mainly affect young people,consequently affecting the workforce.Available treatments are often associated with side effects,and new therapeutic options are needed.For centuries,plants have represented important substrates in the field of drug development.Lafoensia pacari(L.pacari)is a plant whose pharmaceutical potential has been described,and may have biological activity relevant to the treatment of IBD symptoms.AIM To investigate the activity of keto-alcoholic extracts of L.pacari with respect to ameliorating the inflammatory and nociceptive symptoms of acute experimental colitis in mice.METHODS Keto-alcoholic extracts of L.pacari leaves and bark were administered to male andfemale Swiss mice weighing 25 g to 30 g(n=8 male mice and n=8 female mice).The effect of these extracts was observed in an acetic acid-induced acute experimental model of colitis with regard to antinociception/analgesia and inflammatory tissue damage.Recorded macroscopic indices included the Wallace score and the colon weight obtained using a precision scale.Mechanical hyperalgesia was determined using an electronic analgesimeter.Behavior related to overt pain was determined by quantifying the number of writhing instances within 20 min of administration of acetic acid.Molecular docking was performed using human and murine cyclooxygenase-2(COX-2)with 3 flavonoids(ellagic acid,kaempferol,and quercetin)on the AutoDock Vina software.Analysis of variance followed by Tukey’s posttest was used with P<0.05 indicating significance.RESULTS In this murine model of colitis,administration of extracts from L.pacari ameliorated acetic acidinduced writhing and colitis-associated inflammatory pain.These improvements may be attributable to the reduction in edema,inflammation(e.g.,ulcers,hyperemia,and bowel wall damage),and the intensity of abdominal hyperalgesia.The keto-alcoholic extracts of L.pacari leaves and bark administered at a dose of either 100 mg/kg or 300 mg/kg significantly reduced the number of writhing events when compared to the negative control(P<0.05).Additionally,extracts of L.pacari bark also performed better than Dipyrone.Leaf extracts administered at 10 mg/kg,30 mg/kg,and 100 mg/kg and bark extracts administered at 30 mg/kg significantly reduced or prevented the development of edema in the colon of treated mice,while mesalazine did not.Moreover,using molecular docking,we observed that the flavonoids present in L.pacari extracts bind to COX-2,an event not unique to ellagic acid.CONCLUSION The results of this study demonstrate a potential novel application of L.pacari extracts for the reduction of inflammation and promotion of antinociception/analgesia as demonstrated by our findings in a murine model of colitis.These findings were also corroborated by in silico analyses,and suggest that L.pacari extracts may be a promising therapeutic agent in the treatment of IBD.

Clinical implications of forkhead box M1, cyclooxygenase-2, and glucose-regulated protein 78 in breast invasive ductal carcinoma

BACKGROUND Breast infiltrating ductal carcinoma(BIDC)represents the largest heterotypic tumor group,and an in-depth understanding of the pathogenesis of BIDC is key to improving its prognosis.AIM To analyze the expression profiles and clinical implications of forkhead box M1(FOXM1),cyclooxygenase-2(COX-2),and glucose-regulated protein 78(GRP78)in BIDC.METHODS A total of 65 BIDC patients and 70 healthy controls who presented to our hospital between August 2019 and May 2021 were selected for analysis.The peripheral blood FOXM1,COX-2,and GRP78 levels in both groups were measured and the association between their expression profiles in BIDC was examined.Additionally,we investigated the diagnostic value of FOXM1,COX-2,and GRP78 in patients with BIDC and their correlations with clinicopathological features.Furthermore,BIDC patients were followed for 1 year to identify factors influencing patient prognosis.RESULTS The levels of FOXM1,COX-2,and GRP78 were significantly higher in BIDC patients compared to healthy controls(P<0.05),and a positive correlation was observed among them(P<0.05).Receiver operating characteristic analysis demonstrated that FOXM1,COX-2,and GRP78 had excellent diagnostic value in predicting the occurrence of BIDC(P<0.05).Subsequently,we found significant differences in FOXM1,COX-2,and GRP78 levels among patients with different histological grades and metastasis statuses(with vs without)(P<0.05).Cox analysis revealed that FOXM1,COX-2,GRP78,increased histological grade,and the presence of tumor metastasis were independent risk factors for prognostic death in BIDC(P<0.001).CONCLUSION FOXM1,COX-2,and GRP78 exhibit abnormally high expression in BIDC,promoting malignant tumor development and closely correlating with prognosis.These findings hold significant research implications for the future diagnosis and treatment of BIDC.

Role of cyclooxygenase-2 in gastric cancer development and progression

Although the incidence of gastric cancer has been declining in recent decades,it remains a major public health issue as the second leading cause of cancer death worldwide.In China,gastric cancer is still the main cause of death in patients with malignant tumors.Most patients are diagnosed at an advanced stage and mortality is high.Cyclooxygenase-2(COX-2)is a ratelimiting enzyme in prostanoid synthesis and plays an important role in the development and progression of gastric cancer.The expression of COX-2 in gastric cancer is upregulated and its molecular mechanisms have been investigated.Helicobacter pylori infection,tumor suppressor gene mutation and the activation of nuclear factor-kappa B may be responsible for the elevated expression of COX-2 in gastric cancer.The mechanisms of COX-2 in the development and progression of gastric cancer are probably through promoting the proliferation of gastric cancer cells,while inhibiting apoptosis,assisting angiogenesis and lymphatic metastasis,and participating in cancer invasion and immunosuppression.This review is intended to discuss,comment and summarize recent research progress on the role of COX-2 in gastric cancer development and progression,and elucidate the molecular mechanisms which might be involved in the carcinogenesis.

Helicobacter pylori infection, gastrin and cyclooxygenase-2 in gastric carcinogenesis

Gastric cancer is one of the most frequent neoplasms and a main cause of death worldwide, especially in China and Japan. Numerous epidemiological, animal and experimental studies support a positive association between chronic Helicobacter pylori(H. pylori) infection and the development of gastric cancer. However, the exact mechanism whereby H. pylori causes gastric carcinogenesis remains unclear. It has been demonstrated that expression of cyclooxygenase-2(COX-2) is elevated in gastric carcinomas and in their precursor lesions. In this review, we present the latest clinical and experimental evidence showing the role of gastrin and COX-2 in H. pylori-infected patients and their possible association with gastric cancer risk.

Cyclooxygenase-2 and the inflammogenesis of breast cancer

Cohesive scientific evidence from molecular, animal, and human investigations supports the hypothesis that constitutive overexpression of cyclooxygenase-2(COX-2) is a ubiquitous driver of mammary carcinogenesis, and reciprocally, that COX-2 blockade has strong potential for breast cancer prevention and therapy. Key findings include the following:(1) COX-2 is constitutively expressed throughout breast cancer development and expression intensifies with stage at detection, cancer progression and metastasis;(2) essential features of mammary carcinogenesis(mutagenesis, mitogenesis, angiogenesis, reduced apoptosis, metastasis and immunosuppression) are linked to COX-2-driven prostaglandin E2(PGE-2) biosynthesis;(3) upregulation of COX-2 and PGE-2 expression induces transcription of CYP-19 and aromatase-catalyzed estrogen biosynthesis which stimulates unbridled mitogenesis;(4) extrahe-patic CYP-1B1 in mammary adipose tissue converts paracrine estrogen to carcinogenic quinones with mutagenic impact; and(5) agents that inhibit COX-2 reduce the risk of breast cancer in women without disease and reduce recurrence risk and mortality in women with breast cancer. Recent sharp increases in global breast cancer incidence and mortality are likely driven by chronic inflammation of mammary adipose and upregulation of COX-2 associated with the obesity pandemic. The totality of evidence clearly supports the supposition that mammary carcinogenesis often evolves as a progressive series of highly specific cellular and molecular changes in response to induction of constitutive overexpression of COX-2 and the prostaglandin cascade in the "inflammogenesis of breast cancer".

Effects of bile acids on cyclooxygenase-2 expression in a rat model of duodenoesophageal anastomosis

AIM:To examine the expression of cyclooxygenase-2(COX-2)and prostaglandin E2(PGE2)in rat esophageal lesions induced by reflux of duodenal contents.METHODS:Thirty 8-week-old male Wistar rats were exposed to duodenal content esophageal reflux.All animals underwent an esophagoduodenal anastomosis(EDA)with total gastrectomy to elicit chronic esophagitis.In ten rats sham operations with only a midline laparotomy were performed(Control).The rats were sacrificed at the 40th week,their esophagi were taken for hematoxylin and eosin staining and for examination of expression of COX2,PGE2,and proliferating cell nuclear antigen(PCNA),and total bile acids in the esophageal lumen was measured.RESULTS:After 40 wk of reflux,columnar dysplasia,squamous cell carcinoma and adenocarcinoma were observed.Total bile acids in the esophageal lumen were significantly increased in the EDA group compared with the sham operated rats.PCNA labelling index and esophageal tissue PGE2 levels were higher in dysplastic and cancer tissues than in control tissues.Overexpression of COX2 was observed in dysplastic and cancer tissues.CONCLUSION:Reflux of duodenal contents induces COX2 expression and increases prostaglandin synthesis in dysplastic and cancer tissues.This result suggests a possible mechanism by which bile acids promote esophageal cancer.

Interaction between cyclooxygenase-2,Snail,and E-cadherin in gastric cancer cells

AIM:To investigate the mechanisms of how cyclooxygenase-2(COX-2)regulates E-cadherin in gastric cancer cells.METHODS:COX-2 expression in human gastric cancer cell lines SGC-7901,BGC-823,MGC-803 and AGS were measured at the mRNA and protein level.COX-2 rich cell line SGC-7901 was chosen for subsequent experiments.siRNA mediated gene knockdown was used to investigate the impact of COX-2 on nuclear factor-κB (NF-κB),Snail,and E-cadherin in gastric cancer cells.Gene expression was determined by Western blot and real-time polymerase chain reaction.To analyze whether NF-κB inhibition could interrupt the modulatory effect of COX-2 or prostaglandin E2(PGE2)on E-cadherin,gastric cancer cells were treated with celecoxib or PGE2,in the presence of NF-κB specific siRNA.RESULTS:Highest expression level of COX-2 was found in SGC-7901 cells,both at mRNA and protein levels.siRNA mediated down-regulation of COX-2 led to a reduced expression of NF-κB and Snail,but an increased expression of E-cadherin in SGC-7901 cells.siRNA mediated down-regulation of NF-κB also led to a reduced expression of E-cadherin and Snail in SGC-7901 cells.However,COX-2 expression did not alter after cells were treated with NF-κB specific siRNA in SGC-7901 cells.Treatment of SGC-7901 cells with celecoxib led to a reduced expression of Snail but an increased expression of E-cadherin.In contrast,treatment of SGC-7901 cells with PGE2 led to an increased Snail and a decreased E-cadherin.However,siRNAmediated knockdown of NF-κB partially abolished the effect of celecoxib and PGE2 on the regulation of E-cadherin and Snail in SGC-7901 cells.CONCLUSION:COX-2 likely functions upstream of NF-κB and regulates the expression of E-cadherin via NF-κB/Snail signaling pathway in gastric cancer cells.

Involvement of eicosanoids in the pathogenesis of pancreatic cancer: the roles of cyclooxygenase-2 and 5-lipoxygenase

The interplay between inflammation and cancer progression is a growing area of research. A combination of clinical, epidemiological, and basic science investigations indicate that there is a relationship between inflammatory changes in the pancreas and neoplastic progression. Diets high in ω-6 polyunsaturated fatty acids provide increased substrate for arachidonic acid metabolism by cyclooxygenase-2(COX-2) and 5-lipoxygenase(5-LOX) to form eicosanoids. These eicosanoids directly contribute to pancreatic cancer cell proliferation. Both COX-2 and 5-LOX are upregulated in multiple cancer types, including pancreatic cancer. In vitro studies using pancreatic cancer cell lines have demonstrated upregulation of COX-2 and 5-LOX at both the mRNA and protein levels. When COX-2 and 5-LOX are blocked via a variety of mechanisms, cancer cell proliferation is abrogated both in vitro and in vivo.The mechanism of COX-2 has been shown to include effects on apoptosis as well as angiogenesis. 5-LOX has been implicated in apoptosis. The use of COX-2 and 5-LOX inhibitors in clinical studies in patients with pancreatic cancer has been limited. Patient enrollment has been restricted to those with advanced disease which makes evaluation of these drugs as chemopreventive agents difficult. COX-2 and 5-LOX expression have been shown to be present during the early neoplastic changes of pancreatic cancer, well before progression to invasive disease. This indicates that the ideal role for these interventions is early in the disease process as preventive agents, perhaps in patients with chronic pancreatitis or hereditary pancreatitis.

Cyclooxygenase-2 plays a central role in the genesis of pancreatitis and associated lung injury

BACKGROUND: The exact mechanism by which cyclooxy- genase-2 (COX-2) promotes inflammation in pancreatitis in obscure. This study was undertaken to investigate the role of COX-2 inhibition in an animal model of pancreati- tis , a disease process characterized by a systemic inflamma- tory response and ensuing neutrophil-mediated lung injury. METHODS: Pancreatitis was induced in 24 Sprague-Daw- ley rats by intraperitoneal injection of 20% L-arginine (500 mg/100 g body weight). The animals were randomized into 3 groups (8 rats in each group); controls and rats with pancreatitis intravenously resuscitated with either normal saline (0.9% NaCl 3 ml/kg) at 24 and 48 hours or COX-2 inhibitor (parecoxib 1 mg/kg). Pancreatic and lung inju- ries were assessed histologically. Lung injury was assessed utilizing wet;dry ratio and myeloperoxidase activity to in- dicate pulmonary neutrophil infiltration. A Western blot was used to determine COX-2 protein expression in pancrea- tic tissue. RESULTS: The animals treated with COX-2 inhibitors dis- played significantly less pancreatic and lung injuries than their normal saline counterparts. Histological pancreatic and lung injury scores were significantly reduced (P <0.05) in the COX-2 treated group. Lung wet: dry ratios were sig- nificantly improved and pulmonary neutrophil infiltration was attenuated in the COX-2 group (P<0.05). Western blot analysis confirmed attenuated COX-2 protein expression. CONCLUSION: This study shows, for the first time in a rat model, that adjuvant COX-2 inhibition significandy attenu- ates the severity of both pancreatitis and its associated sys- temic inflammatory response and end-organ injury.

Opioid-sparing effect of selective cyclooxygenase-2 inhibitors on surgical outcomes after open colorectal surgery within an enhanced recovery after surgery protocol

AIM: To evaluate the opioid-sparing effect of selective cyclooxygenase-2(COX-2) inhibitors on short-term surgical outcomes after open colorectal surgery.METHODS: Patients undergoing open colorectal resection within an enhanced recovery after surgery protocol from 2011 to 2015 were reviewed. Patients with combined general anesthesia and epidural anesthesia, and those with acute colonic obstruction or perforation were excluded. Patients receiving selective COX-2 inhibitor were compared with well-matched individuals without such a drug. Outcome measures included numeric pain score and morphine milligram equivalent(MME) consumption on postoperative day(POD) 1-3, gastrointestinal recovery(time to tolerate solid diet and time to defecate), complications and length of postoperative stay.RESULTS: There were 75 patients in each group. Pain score on POD 1-3 was not significantly different between two groups. However, MME consumption and MME consumption per kilogram body weight on POD 1-3 was significantly less in patients receiving a selective COX-2 inhibitor(P < 0.001). Median MME consumption per kilogram body weight on POD 1-3 was 0.09, 0.06 and nil, respectively in patients receiving a selective COX-2 inhibitor and 0.22, 0.25 and 0.07, respectively in the comparative group(P < 0.001), representing at least 59% opioidreduction. Patients prescribing a selective COX-2 inhibitor had a shorter median time to resumption of solid diet [1(IQR 1-2) d vs 2(IQR 2-3) d; P < 0.001] and time to first defecation [2(IQR 2-3) d vs 3(IQR 3-4) d; P < 0.001]. There was no significant difference in overall postoperative complications between two groups. However, median postoperative stay was significantly 1-d shorter in patients prescribing a selective COX-2 inhibitor [4(IQR 3-5) d vs 5(IQR 4-6) d; P < 0.001]. CONCLUSION: Perioperative administration of oral selective COX-2 inhibitors significantly decreased intravenous opioid consumption, shortened time to gastrointestinal recovery and reduced hospital stay after open colorectal surgery.

Cyclooxygenase-2 expression is associated with initiation of hepatocellular carcinoma, while prostaglandin receptor-1 expression predicts survival

AIM to determine whether cyclooxygenase-2(COX-2) and prostaglandin E1 receptor(EP1) contribute to disease and whether they help predict prognosis.METHODS We retrospectively reviewed the records of 116 patients with hepatocellular carcinoma(HCC) who underwent surgery between 2008 and 2011 at our hospital. Expression of COX-2 and EP1 receptor was examined by immunohistochemistry of formalin-fixed, paraffinembedded tissues using polyclonal antibodies. Possible associations between immunohistochemical scores and survival were determined.RESULTS Factors associated with poor overall survival(OS) were alpha-fetoprotein > 400 ng/m L, tumor size ≥ 5 cm, and high EP1 receptor expression, but not high COX-2 expression. Disease-free survival was not significantly different between patients with low or high levels of COX-2 or EP1. COX-2 immunoreactivity was significantly higher in well-differentiated HCC tissues(Edmondson grade Ⅰ-Ⅱ) than in poorly differentiated tissues(Edmondson grade Ⅲ-Ⅳ)(P = 0.003). EP1 receptor immunoreactivity was significantly higher in poorly differentiated tissue than in well-differentiated tissue(P = 0.001).CONCLUSION COX-2 expression appears to be linked to early HCC events(initiation), while EP1 receptor expression may participate in tumor progression and predict survival.

Genetic variant of cyclooxygenase-2 in gastric cancer:More inflammation and susceptibility

Gastric cancer accounts for the majority cancer-related deaths worldwide.Although various methods have considerably improved the screening,diagnosis,and treatment of gastric cancer,its incidence is still high in Asia,and the 5-year survival rate of advanced gastric cancer patients is only 10%-20%.Therefore,more effective drugs and better screening strategies are needed for reducing the incidence and mortality of gastric cancer.Cyclooxygenase-2(COX-2)is considered to be the key inducible enzyme in prostaglandins(PGs)synthesis,which is involved in multiple pathways in the inflammatory response.For example,inflammatory cytokines stimulate innate immune responses via Toll-like receptors and nuclear factor-kappa B to induce COX-2/PGE2 pathway.In these processes,the production of an inflammatory microenvironment promotes the occurrence of gastric cancer.Epidemiological studies have also indicated that non-steroidal antiinflammatory drugs can reduce the risk of malignant tumors of the digestive system by blocking the effect of COX-2.However,clinical use of COX-2 inhibitors to prevent or treat gastric cancer may be limited because of potential side effects,especially in the cardiovascular system.Given these side effects and low treatment efficacy,new therapeutic approaches and early screening strategies are urgently needed.Some studies have shown that genetic variation in COX-2 also play an important role in carcinogenesis.However,the genetic variation analysis in these studies is incomplete and isolated,pointing out only a few single nucleotide polymorphisms(SNPs)and the risk of gastric cancer,and no comprehensive study covering the whole gene region has been carried out.In addition,copy number variation(CNV)is not mentioned.In this review,we summarize the SNPs in the whole COX-2 gene sequence,including exons,introns,and both the 5’and 3’untranslated regions.Results suggest that COX-2 does not increase its expression through the CNV and the SNPs in COX-2 may serve as the potential marker to establish risk stratification in the general population.This review synthesizes emerging insights of COX-2 as a biomarker in multiple studies,summarizes the association between whole COX-2 sequence variation and susceptibility to gastric cancer,and discusses the future prospect of therapeutic intervention,which will be helpful for early screening and further research to find new approaches to gastric cancer treatment.

Cyclooxygenase-2 expression is dependent upon epidermal growth factor receptor expression or activation in androgen independent prostate cancer

Aim： To investigate the expression of cyclooxygenase-2 （COX-2） and epidermal growth factor receptor （EGFR） and the possible mechanism in the development in androgen independent prostate cancer （AIPC）. Methods： Immunohistochemistry was performed on paraffin-embedded sections with goat polyclonal against COX-2 and mouse monoclonal antibody against EGFR in 30 AIPC and 18 androgen dependent prostate cancer （ADPC） specimens. The effect of epidermal growth factor （EGF） treatments on the expression of COX-2 and signal pathway in PC-3 and DU-145 cells was studied using reverse transcription-polymerase chain reaction （RT-PCR） and Western blot analysis. ELISA was used to measure prostaglandin E2 （PGE2） levels in the media of PC-3 and DU-145 incubated with EGF for 24 h. Results： COX-2 was positively expressed in AIPC and ADPC, which were predominantly in endochylema of prostate cancer （PCa） cells. Intense staining was seen in AIPC （80%） and in ADPC （55.5%）, but there was no significant association between the two groups. EGFR expression was also positive in the two groups （61.8% in ADPC and 90% in AIPC, P 〈 0.01）. A significant association was found between EGFR expression and a higher Gleason score （P 〈 0.05） or tumor stage （P 〈 0.05）. The expression of PGE2 was increased in PC-3 and DU-145 cells after being incubated with EGF. Both p38MAPK and PI-3K pathway were involved in the PC-3 cell COX-2 upregulation course. In DU- 145, only p38MAPK pathway was associated with COX-2 upregulation. Conclusion： EGFR activation induces COX-2 expression through PI-3K and/or p38MAPK pathways. COX-2 and EGFR inhibitors might have a cooperative anti-tumor effect in PCa.

Celecoxib Inhibits Proliferation and Induces Apoptosis via Cyclooxygenase-2 Pathway in Human Pancreatic Carcinoma Cells

In order to evaluate the effects and mechanisms of celecoxib in inhibiting proliferation and inducing apoptosis on human pancreatic carcinoma cells, the anti-proliferative effect was measured by using methabenzthiazuron (MTT) assay. Cell cycle and apoptosis were analyzed by using flow cytometry (FCM), and the PGE 2 levels in the supernatant of cultured pancreatic carcinoma cells were quantitated by enzyme-linked immunoabsordent assay (ELISA). Our results showed that celecoxib suppressed the production of PGE 2 and inhibited the growth of JF-305 cells, and the anti-proliferative effect of celecoxib could be abolished by addition of PGE 2. FCM revealed that celecoxib could inhibit proliferation and induce apoptosis by G 1-S cell cycle arrest. It was concluded that cyclooxygenase-2 specific inhibitor celecoxib could inhibit proliferation and induced apoptosis of human pancreatic carcinoma cells via suppression of PGE 2 production in vitro.

Acetyl-11-keto-β-boswellic acid inhibits proliferation and induces apoptosis of gastric cancer cells through the phosphatase and tensin homolog/Akt/cyclooxygenase-2 signaling pathway

BACKGROUND Gastric cancer is one of the most common malignant tumors of the digestive system worldwide,posing a serious danger to human health.Cyclooxygenase(COX)-2 plays an important role in the carcinogenesis and progression of gastric cancer.Acetyl-11-keto-β-boswellic acid(AKBA)is a promising drug for cancer therapy,but its effects and mechanism of action on human gastric cancer remain unclear.AIM To evaluate whether the phosphatase and tensin homolog(PTEN)/Akt/COX-2 signaling pathway is involved in the anti-tumor effect of AKBA in gastric cancer.METHODS Human poorly differentiated BGC823 and moderately differentiated SGC7901 gastric cancer cells were routinely cultured in Roswell Park Memorial Institute 1640 medium supplemented with 10%fetal bovine serum and 1%penicillin/streptomycin.Gastric cancer cell proliferation was determined by methyl thiazolyl tetrazolium colorimetric assay.Apoptosis was measured by flow cytometry.Cell migration was assessed using the wound-healing assay.Expression of Bcl-2,Bax,proliferating cell nuclear antigen,PTEN,p-Akt,and COX-2 were detected by Western blot analysis.A xenograft nude mouse model of human gastric cancer was established to evaluate the anti-cancer effect of AKBA RESULTS AKBA significantly inhibited the proliferation of gastric cancer cells in a dose-and time-dependent manner,inhibited migration in a time-dependent manner,and induced apoptosis in a dose-dependent manner in vitro;it also inhibited tumor growth in vivo.AKBA up-regulated the expression of PTEN and Bax,and downregulated the expression of proliferating cell nuclear antigen,Bcl-2,p-Akt,and COX-2 in a dose-dependent manner.The PTEN inhibitor bpv(Hopic)reversed the high expression of PTEN and low expression of p-Akt and COX-2 that were induced by AKBA.The Akt inhibitor MK2206 combined with AKBA downregulated the expression of p-Akt and COX-2,and the combined effect was better than that of AKBA alone.CONCLUSION AKBA inhibits the proliferation and migration and promotes the apoptosis of gastric cancer cells through the PTEN/Akt/COX-2 signaling pathway.

Expression of cyclooxygenase-2 and its pathogenic effects in nonalcoholic fatty liver disease

Objective：To investigate the expression of cyclooxygenase-2 and its pathological effect in the experimental nonalcoholic fatty liver of rats, and to explore its possible mechanism. Methods：The rat NAFLD model was established by giving a fat-enriched diet. The blood samples were obtained form abdominal aorta and the levels of serum ALT, AST and IL-1, changes in the hepatic tissue 6-k-PGF1 α TXB2 were measured. The expression level of COX-2 in rats livers were assayed by immunohistochemistry, RT-PCR and Westernblot. Results： Light microscope analysis revealed that hepatocytes were injured in the model group and slightly in the treatment group. The levels of serum TXB2 and IL-1 in the fatty liver rats were increased. Compared with the model group, the IL-1 and TXB2 increased significantly（P〈 0.05）, on the contrary, compared with the normal group, the hepatic tissue 6-Keto-prostagland decreased significantly in the model group（P 〈 0.05）, the treatment group also increased but P 〉 0.05. There was no positive expression of COX-2 in hepatic tissue of normal rats. In the model group, there was positive expression of COX-2 antigen and the number of COX positive cells progressively increased at 4, 8, 12 wks. The intensity of expression of COX-2 had significantly increased（P 〈 0.05 ） and the intensity of COX-2 expression in the treated group decreased remarkably compared with the model group（P 〈 0.05）. The expression of COX-2 mRNA and the level of COX-2 protein were significantly stronger in the liver of model rats compared with normal rats, and significantly weaker in treated rats, than in 8W and 12W model rats（P 〈 0.05）. Conclusion：The increase of COX-2 expression in NAFLD is closely associated with the severity of liver inflammation and damage. COX-2 may play an important role in the progression of rat NAFLD, and the expression of COX-2 mRNA is downregulated by cyclooxygenase-2 inhibitor, which can depress the oxidative stress and control inflammatory response efficiently.

Pelvic lipomatosis with cystitis glandularis managed with cyclooxygenase-2 inhibitor:A case report

BACKGROUND Pelvic lipomatosis(PL)is a rare benign condition with characteristic overgrowth of histologically benign fat and invasion and compression of pelvic organs,often leading to non-specific lower urinary tract symptoms(LUTS).Approximately 40%of patients with PL have cystitis glandularis(CG).The cause of PL combined with CG is poorly understood,and there is currently no effective treatment.Refractory CG with upper urinary tract obstruction even requires partial or radical bladder resection.CASE SUMMARY In this case,a patient suffering from PL with CG was treated by transurethral resection of bladder tumour(TUR-BT)and oral administration of celecoxib,a selective cyclooxygenase-2(COX-2)inhibitor.The LUTS were alleviated,and the cystoscopy results improved significantly.Immunohistochemistry showed upregulated COX-2 expression in the epithelium of TUR-BT samples,suggesting that COX-2 may participate in the pathophysiological process of PL combined with CG.CONCLUSION We report for the first time that celecoxib may be an effective treatment strategy for PL combined with refractory CG.

UP-REGULATION OF CYCLOOXYGENASE-2 GENE EXPRESSION CORRELATES WITH TUMOR ANGIOGENESIS IN HUMAN BREAST CANCER

Objective: To study the relationship between cyclooxygenase-2 (COX-2) expression and tumor angiogenesis in human breast cancer. Methods: Archival primary breast carcinomas (n = 62), adjacent ductal carcinoma in situ (DCIS, n = 13) and DCIS alone (n = 5) were analyzed for COX-2 and VEGF expression by immunohistochemistry using specific monoclonal antibodies. Microvessel density (MVD) was also examined the using CD34 staining. Results: A significant correlation was found between COX-2 and VEGF expression (P<0.01). Both COX-2 and VEGF were significantly correlated with MVD (P<0.05) and P<0.01, respectively). COX-2 and VEGF genes were overexpressed in tumor specimens as compared with normal epithelia. Conclusion: COX-2 is related to tumor angiogenesis in breast cancer. It is likely that VEGF is one of the most important mediators of the COX-2 angiogenic pathway.

Cyclooxygenase-2 Blockade Inhibits Accumulation and Function of Myeloid-derived Suppressor Cells and Restores T Cell Response after Traumatic Stress

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 CD1 lb＋/Gr-l＋ cells, proliferation and apoptosis of CD4＋ T cells were determined. Ar- ginase activity and arginase-1 （Arg-1） protein expression of splenic CDllb＋/Gr-I＋ cells, and de- layed-type hypersensitivity （DTH） response were analyzed. The results showed that Cox-2 blockade significantly decreased the percentages of CD1 lb＋/Gr-l＋ 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 CD1 lb＋/Gr-l＋ ceils. 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.