Cyclooxygenase-2 Staining Research Articles

Adenovirus-Mediated Anti-Sense ERK2 Gene Therapy Ameliorates Transplant Arteriosclerosis through Inhibiting Activation of Vascular Smooth Muscle Cells and Angiogenesis

The aim of this study is to explore the underlying mechanisms of transplant arteriosclerosis (TA) based on intimal thickening, involving activation of vascular smooth muscle cells (VSMCs) and angiogenesis. The effect of Adenovirus mediated anti-sense ERK2 (Adanti-ERK2) gene therapy on TA is also to be examined. Methods: A rat aorta transplantation model (BN→Lewis) was employed. The animals were divided into: (1) the isograft group (n=6), (2) the empty control group (n=6), (3) the Ad-LacZ group (n=6), and (4) the adanti-ERK2 group (n=6). At 60 days after transplantation, the grafts were collected for pathology. The ratio of intima/(intima□media) was documented. The staining of α-actin and PDGF-BB was performed to analyze migration and secretion of VSMCs. The angiogenesis was evaluated and the COX-2 staining was detected. Result: The isografts showed a normal histology, the allografts from the empty control group and the Ad-LacZ group displayed a typical TA lesion, while the pathology was significant improved in the adanti-ERK2 group. The ratio of intima/(intima+media) were 7.6±2.1%, 81.4±6.7%, 85.9±9.4%, and 15.9±4.1% in the isograft group, the empty control group, the Ad-LacZ group, and the adanti-ERK2 group, respectively. The α-actin+ cells in the intima per vision filed (x400) were 2.1±1.1, 71.3±9.2, 76.4±11.3, and 34.8±5.3, the PDGF-BB+ cells were 0.9±0.5, 28.4±3.4, 29.1±3.2, and 8.6±1.7, the COX-2+ cells in the new capillaries were none, 36.3±8.3, 40.9±9.2, and 10.4±3.9. P< 0.05 was observed between the isograft group, the empty control and the Ad-LacZ group, and the Adanti-ERK2 group. Conclusion: Intimal thickening is one key feature of TA. The mechanisms involve the activation of VSMC (proliferation, migration and secretion), and the accompanying angiogenesis. Adanti-ERK2 gene therapy modulates the mechanisms, and protects allograft against TA.

Abstract A60: Late stage intestinal polyps in ApcMin/+ mice are resistant to treatment with retinoids and TRAIL due to up-regulation of pro-survival proteins.

Abstract The purpose of this study is to determine the mechanism of apoptotic resistance observed in advanced polyps in a mouse model of Familial Adenomatous Polyposis (FAP). FAP is an autosomal dominantly inherited disorder caused by mutations in the tumor suppressor Apc (adenomatous polyposis coli) gene, which results in the formation of hundreds to thousands of polyps, predominantly in the colon and rectum. Left untreated, these polyps will form colorectal adenocarcinomas. Although surgical removal of the colon eliminates the colon cancer risk, these individuals are also at increased risk for other primary cancers, including tumors of the small intestine and stomach. Systemic chemopreventive interventions to specifically remove the pre-cancerous cells in these individuals could greatly improve their outcomes and quality of life. Recently, we have developed a new method based on the ability of combined retinoid and TRAIL (tumor necrosis factor related apoptosis inducing ligand) treatment to induce apoptosis and regression of intestinal polyps in ApcMin/+ mice, a mouse model of FAP. Treatment of these mice with retinoid causes an increase in TRAIL death receptors DR4 and DR5 as well as a concomitant decrease in the decoy receptors. APC deficiency leads to a decreased level of the anti-apoptotic protein FLIP (flice-like inhibitory protein). Thus, the combination of TRAIL and retinoid specifically targets APC deficient cells for apoptosis. We have further determined that early stage intestinal polyps in the ApcMin/+ mouse respond readily to this treatment combination, while late stage polyps are resistant to this treatment. Following up on these findings, we have tested the hypothesis that late stage adenomas of the intestine are resistant to TRAIL and retinoid treatment due to increased inflammatory signaling, resulting in increased anti-apoptotic signaling. We used ApcMin/+ mice at either two months of age or five-six months of age. Adenomas from young mice and older mice were subjected to immunoblot and immunohistochemistry comparing the levels of anti-apoptotic proteins as well as markers of inflammation. Results: Polyps from older mice expressed markedly increased levels of the anti-apoptotic proteins FLIP (flice-like inhibitory protein), XIAP (x-linked inhibitor of apoptosis) and Bcl-2. These polyps also exhibited increased staining for the pro-inflammatory protein cox-2 (cyclooxygenase-2) and the transcription factor NFκB (nuclear factor kappa B). Conclusion: The increased inflammation known to occur in older ApcMin/+ mice leads to an increase in pro-survival proteins that inhibits induction of apoptosis. This suggests that pre-treatment with an anti-inflammatory agent such as sulindac might sensitize adenomas in older mice to retinoid and TRAIL treatment for the induction of apoptosis. Citation Format: Jennifer S. Davis, Shaoyi Huang, Xiaoyang Ren, Zhengming Xu, Ernest Hawk, Xiangwei Wu. Late-stage intestinal polyps in ApcMin/+ mice are resistant to treatment with retinoids and TRAIL due to upregulation of prosurvival proteins. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr A60.

538P - The Role of Cox-2 and KI-67 Overexpression in the Prediction of Pathologic Response of Rectal Cancer to Neoadjuvant Chemoradiation Therapy

ABSTRACT Background The response to neoadjuvant chemoradiotherapy (CRT) is not the same among all cases with advanced rectal cancer. Aims: In this study, we investigated the association between overexpression of two molecular markers (COX-2 and Ki-67) and tumor response to neoadjuvant therapy. Design: A retrospective cohort study. Materials and methods Forty five patients with stage II-III rectal carcinoma were enrolled. All patients were treated with neoadjuvant therapy (45-50.4 Gy plus Capecitabin) between 2002 and 2009 in our institute. The pretreatment specimens were IHC stained for COX-2 and Ki-67 markers. The tumor response to neoadjuvant treatment was evaluated using a 5 point tumor regression grade (TRG) system. The induced inflammation and necrosis after chemoradiotherapy were also investigated. Statistical analysis: Statistical analysis was performed using SPSS version 11.5 and statistical significance was determined at P Results The pathologic response to neoadjuvant treatment from complete response as (TRG = 1) through no response as (TRG = 5) was found in 10 (22.2%), 8 (17%), 6 (13.3%), 16 (35.6%), and 5 (11.1%) cases. In comparison with poor responders (TRG: 4,5), patients with good response to neoadjuvant treatment (TRG: 1,2) were associated with lower pretreatment mean COX-2 staining extent (72.9% vs. 22.8%, P Conclusions Overexpression of COX-2 and high Ki-67 index were associated with a poorer response to neoadjuvant chemoradiotherapy. These markers might be helpful to define those patients with rectal carcinoma who benefit more from neoadjuvant treatments. Disclosure All authors have declared no conflicts of interest.

Sodium arsenite-induced abnormalities in expressions of Caveolin-1, eNOS, IKKβ, and COX-2 in SV-40 immortalized human uroepithelial cells and in urothelial carcinomas

Arsenic, a known human carcinogen, is found throughout the crust of the earth. Prolonged arsenic exposure is a known cause of urothelial carcinoma (UC) and blackfoot disease (BFD). The aim of this study was to determine the effect of sodium arsenite on Caveolin-1 and downstream signaling molecules (eNOS, IKKβ and COX-2) expression in human urothelial cells (SV-HUC-1). Immunohistochemical (IHC) staining of Caveolin-1, eNOS, IKKβ, and COX-2 was also compared between UC patients from endemic and non-endemic areas of BFD in Taiwan. Immunocytochemical staining and Western blotting results revealed increased expression of Caveolin-1, IKKβ, and COX-2 but decreased eNOS in SV-HUC-1 cells treated with low concentration of arsenite. Additionally, MEK inhibitor (U0126) significantly attenuated arsenite-induced expression of Caveolin-1, IKKβ and COX-2 while reducing eNOS expression. The IHC staining of UCs revealed that expressions of Caveolin-1, IKKβ, and COX-2 were significantly higher in patients from endemic areas of BFD compared to patients from non-endemic areas (p=0.011, p=0.002, p=0.0001) whereas eNOS was significantly lower (p=0.0001). The correlation observed between Caveolin-1 and downstream signaling molecule expression may be an important mechanism of arsenic-induced urothelial carcinogenesis.

The Role of Cyclooxygenase-2 in Mechanical Ventilation–Induced Lung Injury

Mechanical ventilation is necessary for patients with acute respiratory failure, but can cause or propagate lung injury. We previously identified cyclooxygenase-2 as a candidate gene in mechanical ventilation-induced lung injury. Our objective was to determine the role of cyclooxygenase-2 in mechanical ventilation-induced lung injury and the effects of cyclooxygenase-2 inhibition on lung inflammation and barrier disruption. Mice were mechanically ventilated at low and high tidal volumes, in the presence or absence of pharmacologic cyclooxygenase-2-specific inhibition with 3-(4-methylsulphonylphenyl)-4-phenyl-5-trifluoromethylisoxazole (CAY10404). Lung injury was assessed using markers of alveolar-capillary leakage and lung inflammation. Cyclooxygenase-2 expression and activity were measured by Western blotting, real-time PCR, and lung/plasma prostanoid analysis, and tissue sections were analyzed for cyclooxygenase-2 staining by immunohistochemistry. High tidal volume ventilation induced lung injury, significantly increasing both lung leakage and lung inflammation relative to control and low tidal volume ventilation. High tidal volume mechanical ventilation significantly induced cyclooxygenase-2 expression and activity, both in the lungs and systemically, compared with control mice and low tidal volume mice. The immunohistochemical analysis of lung sections localized cyclooxygenase-2 expression to monocytes and macrophages in the alveoli. The pharmacologic inhibition of cyclooxygenase-2 with CAY10404 significantly decreased cyclooxygenase activity and attenuated lung injury in mice ventilated at high tidal volume, attenuating barrier disruption, tissue inflammation, and inflammatory cell signaling. This study demonstrates the induction of cyclooxygenase-2 by mechanical ventilation, and suggests that the therapeutic inhibition of cyclooxygenase-2 may attenuate ventilator-induced acute lung injury.

Regulation of inducible heme oxygenase and cyclooxygenase isozymes in a mouse model of spotted fever group rickettsiosis

Vascular endothelial cells (ECs) lining the blood vessels are the preferred primary targets of pathogenic Rickettsia species in the host. In response to oxidative stress triggered by infection, ECs launch defense mechanisms such as expression of heme oxygenase-1 (HO-1). Previous evidence from an established animal model of Rocky Mountain spotted fever also suggests selective modulation of anti-oxidant enzyme activities in the target host tissues. In this study, we have examined the expression profiles of HO-1 and COX-2 in different tissues during Rickettsia conorii infection of susceptible C3H/HeN mice. RNA hybridization with murine HO-1 and COX-2-specific complementary DNA probes revealed increased HO-1 expression in the liver and brain of mice infected with three different doses of R. conorii ranging from 2.25×103 to 2.25×105pfu, relatively non-remarkable changes in the lungs, and a trend for down-regulation in the spleen. The most prominent HO-1 response was evident in the liver with ∼4-fold increase on day 4 post-infection, followed by a decline on day 7. HO-1 expression in the brain, however, peaked with significantly higher levels on day 7. Following infection with both sub-lethal as well as lethal doses of infection, the transcript encoding COX-2 also displayed a pattern of increased expression in the liver and brain. Although immunohistochemical staining revealed increased abundance of HO-1 protein in the liver of infected mice, adjoining serial sections did not exhibit positive staining for COX-2 in infected tissues. The levels of monocyte chemoattractant protein-1 (MCP-1) and keratinocyte-derived cytokine (KC) were significantly higher in the sera of infected mice and corresponded with the onset and severity of the disease. Treatment of infected animals with anti-oxidants α-lipoic acid and N-acetylcysteine and HO inhibitor stannous protoporphyrin (SnPPIX) showed only selective beneficial effects on HO-1 and COX-2 expression in the liver and spleen and serum levels of KC and MCP-1. R. conorii infection of susceptible mice, therefore, results in selective regulation of the expression of HO-1 and COX-2 in a manner dependent on the target host tissue’s cellular environment and the propensity of infection with rickettsiae.

Epithelial to mesenchymal transition in cutaneous squamous cell carcinoma is correlated with COX-2 expression but not with the presence of stromal macrophages or CD10-expressing cells

Epithelial to mesenchymal transition (EMT) is an intricate process by which epithelial cells loose epithelial characteristics and acquire a mesenchymal-like phenotype. EMT and cyclooxygenase 2 (COX-2) expression are related to tumor invasion and metastasis. The tumor microenvironment plays a major role in tumor progression and the induction of EMT. Here, we investigated the relationship between EMT and COX-2 expression as well as tumor-associated macrophages (TAM) and CD10-positive stromal cells during the development of cutaneous squamous neoplastic lesion. We performed immunohistochemical staining for vimentin, E-cadherin, β-catenin, COX-2, CD68, and CD10 in 41 cases of squamous cell cancers (SCC), 20 of Bowen's disease, 30 of actinic keratosis, and 30 samples of normal skin. SCC cells showed significantly increased vimentin expression and reduced expression of membranous E-cadherin and β-catenin compared with cells in precursor lesions and in normal skin. COX-2 expression was also markedly increased in SCC cells. E-cadherin expression was positively correlated with β-catenin expression and inversely correlated with COX-2 expression in SCC cells. The number of TAM and CD10-positive stromal cells increased from the normal skin to precursor lesions and SCC cells. The number of TAM and of CD10-positive stromal cells did not correlate with the expression of E-cadherin, β-catenin, COX-2, and vimentin in SCC cells. We suggest that cutaneous SCC cells show EMT, which appears to be correlated with COX-2 expression but not with stromal CD10 expression and TAM.

The use of molecular markers as a method to predict the response to neoadjuvant therapy for advanced stage rectal adenocarcinoma

The response to combined neoadjuvant therapy for advanced stage rectal adenocarcinoma is predictive of outcome. In addition to both clinical and pathological features, the expression of a variety of molecules may provide another method of identifying tumour responsiveness to pre-operative therapy. The aim of this study was to evaluate several markers in the apoptotic pathway as well as expression of Cox-2 and vascular endothelial growth factor (VEGF) to determine their ability to predict response to neoadjuvant therapy. In total, 152 patients with advanced rectal adenocarcinoma were treated with neoadjuvant therapy followed by resection. Paraffin-embedded sections obtained before and after therapy were assessed by immunohistochemical staining for Cox-2, VEGF, p53, p21, p27, Bax, BCL-2 and apoptosis protease-activating factor 1 (APAF-1). These stains were correlated with tumour regression grade, complete pathological response and T-downstaging of the surgical specimen. Clinical and pathological data were also collected. Data were analysed using the χ2 and Spearman's correlation tests. Pathological complete response was seen in 24.5% of patients. Amongst the apoptosis-associated markers, only APAF-1 expression was found to be significantly associated with tumour regression grade (P<0.001), complete pathological response (P<0.031) and T-downstaging (P<0.004). On multivariate analysis, APAF-1 expression was found to be independently associated with good tumour regression grade. In contrast, overexpression of Cox-2 and VEGF in pretreatment biopsies was related to less tumour regression (P<0.003) and less likelihood of T-downstaging (P<0.03). Immunohistochemical evaluation of initial biopsy specimens of rectal cancer with APAF-1, Cox-2 and VEGF may predict tumour response to neoadjuvant therapy in patients with advanced rectal adenocarcinoma. Those with an expected limited response may be considered for other investigational neoadjuvant protocols.

Cyclooxygenase immunohistochemical staining in the human ductus arteriosus after 24 weeks of gestational age

Cyclooxygenase inhibitors (CI) which contained risks to fetal health were one of the most effective tocolytics. In order to indirectly investigate the effects of CI in human ductus arteriosus, immunohistochemical staining for cyclooxygenase-1 (COX1) and cyclooxygenase-2 (COX2) was evaluated in post-mortem fetuses with gestational ages between 24 and 34 weeks. Neither COX1 nor COX2 staining was related to gestational age. COX1 and COX2 staining in the vessel walls were not related to each other. COX1 staining in the endothelium, inner media and outer media were positively correlated with each other (COX1 endothelium vs IM staining Spearman's rho statistic [rs] = 0.721, p = 0.001; COX1 endothelium vs OM staining [rs] = 0.634, p = 0.004; COX1 IM vs OM staining [rs] = 0.931, p = 0.001). COX2 staining of endothelium was not correlated with either IM or OM staining. In conclusion, COX2 staining in the post-mortem specimens of human ductus arteriosus between 24 and 34 weeks is weak and limited to the endothelium.

Capability of Nondegenerated and Degenerated Discs in Producing Inflammatory Agents With or Without Macrophage Interaction

Molecular biological and immunohistological examinations. To clarify whether nondegenerated and degenerated discs produce inflammatory agents such as prostaglandin (PG)E2, interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)α, which have been reported to play pivotal roles in lumbar disc diseases, in the presence or absence of macrophages. A recent study reported discogenic low back pain might be caused by annular disruption followed by vascularized granulation formation extending from the outer layer of the annulus fibrosus into the nucleus pulposus along the torn fissure. Moreover, abundant macrophages have been shown to be present in symptomatic discs but not in normal and aged discs. However, there has been no in vitro report investigating the interaction between macrophages and several degrees of degenerated discs. Degenerated intervertebral discs were obtained from Sprague-Dawley rats with different lengths of rat tail compression (2, 4, and 8 weeks). These degenerated disc and nondegenerated disc tissues were respectively cultured in the presence or absence of macrophages. The culture supernatants were analyzed for PGE2, IL-6, IL-1β, and TNF-α. Immunohistochemical staining for cyclooxygenase-2 and IL-6 was also carried out on 4-week compression discs. Nondegenerated discs alone, several degrees of degenerated discs alone, and macrophages alone produced small amounts of PGE2 and IL-6. However, they were able to produce significantly higher amounts of PGE2 and IL-6 when cocultured with macrophages. In contrast, we detected small amounts of IL-1β and TNF-α at every stage of degeneration regardless of the presence or absence of macrophages. The immunohistological examination showed anticyclooxygenase-2 and anti-IL-6 reactivities in the chondrocytes embedded in the disc matrix obtained from the degenerated disc. These results suggest PGE2 and IL-6 play a pivotal role in the interaction between degenerated discs and macrophages.

Relationship Between Mast Cell Subtypes and Cyclooxygenase-2 Expression in Uterine Leiomyomas

Objective: Mast cells (MCs) have been proved to be multifunctional cells which are known to be located at peri-and intra-tumoral sites, playing an active role physiologically or pathologically. In humans, MCs are subtyped by the difference in their neutral protease content. MCs that have granules containing tryptase alone (MCT) are predominantly found at mucosal sites. MCs whose granules possess tryptase along with chymase (MCTC) are found especially within connective tissue. MC mediators have different functions and the coexistence of both MC subtypes contributes to tissue homeostasis. Furthermore, cyclooxygenase-2 (COX-2) is an enzyme associated with inflammation, cell growth and differentiation, prevention of apoptosis and tumorigenesis. Recent studies show the clinical significance of COX-2 expression in different tumor types. However, to our knowledge, there is no data assessing the relationship between COX-2 and MC density in uterine leiomyomas. We aimed to investigate the relation between the expression of COX-2, MC density, and proportional changes of MC phenotypes in human leiomyoma uteri and control cases, and also their possible correlations between each other. Methods: We performed a retrospective study of 34 cases carried out on parafin-embedded samples obtained from 14 control (group 1) and 20 leiomyoma uteri (group 2) patients who had undergone curative hysterectomy. These specimens were investigated immunohistochemically by using anti-cyclooxygenase-2 (COX-2) antibodies to stain COX-2; anti-tryptase antibodies to stain MCT and anti-chymase antibodies to stain MCTC. Results: In leiomyoma, the median value of COX-2 staining grade was 2 (min:1-max:3) which was statistically lower than that of controls with a median value of 3 (min:2-max:4) (p=0.001). The median value of tryptase expression was 12 (min:10-max:16) in the control myometrium, slightly higher than that of the leiomyoma group which had a median value of 10.5 (min:6-max:15). On the other hand, the median value of chymase expression was 7 (min:4-max:13) in the control myometrium, which was significantly higher (p=0.001) than that of the leiomyoma group with a median value of 5 (min:2max:8). Thus, in the leiomyoma group, the mast cell subtypes, including tryptase÷chymase proportion, was found to be significantly higher than the controls (p=0.032). Moreover, COX-2, tryptase and chymase expressions showed no correlation in both groups. Conclusion: This study has demonstrated that expressions of COX-2 and mast cell subtypes are reduced in leiomyoma, and the proportion of mast cell subtypes of MCT÷MCTC increases in leiomyoma compared to the control group. However, MC subtypes neither correlated with each other nor with COX-2 expression in the leiomyoma and control series. Understanding the mechanisms for MC functions and the secretory molecules will provide a basis for a rational approach to the development of antitumoral therapy in patients with leiomyoma and other tumors. (JAREM 2011; 1: 44-8)

Cyclooxygenase‐2 expression and clinical parameters in laryngeal squamous cell carcinoma, vocal fold nodule, and laryngeal atypical hyperplasia

The diagnostic role of cyclooxygenase-2 (COX-2) expression in laryngeal atypical hyperplasia, vocal fold nodule, and laryngeal squamous cell carcinoma was examined. Specimens obtained from patients diagnosed with vocal fold nodule (n = 35), atypical hyperplasia (n = 35), laryngeal squamous cell carcinoma (n = 35), and clinical parameters were evaluated retrospectively. Although no staining was observed in patients with vocal fold nodules, staining was noted in laryngeal atypical hyperplasia and squamous cell carcinoma. The percentage of COX-2 staining was the highest in the carcinoma group. It was determined that COX-2 staining was significantly associated with laryngeal squamous cell carcinoma. It should be noted that overexpression of COX-2, a potentially important factor in the evolution of carcinogenesis in precancerous lesions, might be an indicator of the development of carcinoma.

Expression of Cyclooxygenase-2 and Ki-67 in Actinic Keratosis and Cutaneous Squamous Cell Carcinoma in Dogs

Actinic keratosis is a common disease in humans, which also affects dogs. Lesions occur in chronically sun exposed areas, such as flank, ventral and lateral abdomen. It has been reported that actinic keratosis is a pre-neoplastic disease which may evolve into squamous cell carcinoma (SCC), which is one of the most frequent malignant neoplasm in dogs. The aim of this research was to investigate the relationship between COX-2 and cell proliferation on the outcome of dogs with actinic keratosis and cutaneous squamous cell carcinoma. This study included 10 skin sections of actinic keratosis (G1) and 10 cutaneous SCC (G2). Data including age, breed, gender and histopathological findings were documented. Paraffin-embedded tissues were retrieved for COX-2 and Ki-67 staining. American Pit Bull Terrier dogs were the most affected ones in both G1 and G2, the mean age was 4.3 (±0.8) years and 5.6 (±1.7) years, respectively. Mean score of COX-2 immunostaining in G1 and G2 was 8.16 (±3.51) and 8.56 (±1.03), respectively. Mean percentage of immunopositive cells for Ki-67 in G1 and G2 was 15.77 (±8.81) and 17.71 (±12.21), respectively. There was no association between COX-2 expression and Ki-67, recurrence, survival and metastasis rate (p > 0.05). These findings highlight the role of COX-2 and Ki-67 in carcinogenesis, but do not confirm the relationship between COX-2 expression and increased cell proliferation in dogs. COX-2 may play a role in carcinogenesis, but this pathway is not responsible for cellular proliferation in actinic keratosis and cutaneous SCC in dogs. Both markers were not useful tools to differentiate the outcome of affected dogs.

Regional Differences in the Neuronal Expression of Cyclooxygenase-2 (COX-2) in the Newborn Pig Brain

Cyclooxygenase (COX)-2 is the major constitutively expressed COX isoform in the newborn brain. COX-2 derived prostanoids and reactive oxygen species appear to play a major role in the mechanism of perinatal hypoxic-ischemic injury in the newborn piglet, an accepted animal model of the human term neonate. The study aimed to quantitatively determine COX-2 immunopositive neurons in different brain regions in piglets under normoxic conditions (n=15), and 4 hours after 10 min asphyxia (n=11). Asphyxia did not induce significant changes in neuronal COX-2 expression of any studied brain areas. In contrast, there was a marked regional difference in all experimental groups. Thus, significant difference was observed between fronto-parietal and temporo-occipital regions: 59±4% and 67±3% versus 41±2%* and 31±3%* respectively (mean±SEM, data are pooled from all subjects, n=26, *p<0.05, vs. fronto-parietal region). In the hippocampus, COX-2 immunopositivity was rare (highest expression in CA1 region: 14±2%). The studied subcortical areas showed negligible COX-2 staining. Our findings suggest that asphyxia does not significantly alter the pattern of neuronal COX-2 expression in the early reventilation period. Furthermore, based on the striking differences observed in cortical neuronal COX-2 distribution, the contribution of COX-2 mediated neuronal injury after asphyxia may also show region-specific differences.

Maximal Standardized Uptake Value on FDG-PET Is Correlated With Cyclooxygenase-2 Expression in Patients With Lung Adenocarcinoma

Cyclooxygenase-2 (COX-2) is constitutively overexpressed in a variety of epithelial malignancies and is usually associated with a poor prognosis. Fluorodeoxyglucose positron emission tomography (FDG-PET) has become an important tool for the diagnosis and staging of non-small-cell lung cancer. The maximal standardized uptake values (SUVmax) of primary tumors on FDG-PET have been shown to be correlated with some clinicopathologic factors. In this study, we investigated the prediction of intratumoral COX-2 expression by FDG-PET in cases of lung adenocarcinoma. We conducted a retrospective review of the data of 60 patients with lung adenocarcinoma measuring less than 3 cm in diameter. Immunohistochemical staining for COX-2 and other biological factors that might influence cancer progression was performed, and the correlations of the selective tumor marker expression with the SUVmax were evaluated. A significant correlation was observed between the SUVmax and the expressions of COX-2, Ki-67, and vascular endothelial growth factor (VEGF). Multiple stepwise regression analysis revealed significant relationships between the SUVmax and the expression of COX-2 (p<0.001) and Ki-67 (p=0.016). Of the 2, COX-2 expression was the stronger determinant of the SUVmax, which increased in proportion to the score for COX-2 expression. The recurrence-free survival of patients with elevated COX-2 expression was significantly worse than that of patients not showing COX-2 expression. The expression of COX-2 in primary tumors is as strongly correlated with a worse clinical outcome as is increased FDG uptake in cases of lung adenocarcinoma. These findings indicate that the SUVmax of primary tumors might reflect the biological malignant potential in lung adenocarcinomas.

Anti-inflammatory effect of prednisolone on the growth of human liver fluke in experimental opisthorchiasis

Opisthorchis viverrini is one of the risk factors for cholangiocarcinoma (CCA) development and is endemic in Southeast Asia including Thailand. CCA is induced by chronic inflammation from a combination of mechanical damage, parasite secretions, and immunopathology. Chronic infection with O. viverrini has been associated with several hepatobiliary diseases which affect the development of hepatobiliary cancer and CCA. Therefore, reducing the pathogenesis from O. viverrini infection may be one of the choices to reduce the risk of cholangiocarcinoma development. Prednisolone is one of the steroidal anti-inflammatory drugs that suppress inflammation, and its use has risen continuously in recent years. We therefore investigated the effect of prednisolone on pathological changes in Syrian hamster opisthorchiasis, in terms of gross and histopathological changes, worm size, eggs per gram, eggs per worm, and immunohistochemical staining for COX2. Syrian hamsters were divided into three groups: uninfected control; O. viverrini-infected (OV); and O. viverrini-infected plus prednisolone administration (OVP). The results showed an anti-inflammatory effect in the OVP group by a reduction of the inflammatory cells surrounding the intrahepatic bile ducts. However, in addition, parasite sizes for all times of observation were larger than for other groups, which was also correlated with increased eggs per worm and eggs per gram of feces. This result suggests that prednisolone is useful in suppressing inflammation in Syrian hamster opisthorchiasis, whereas it was also beneficial for parasites by enhancing their reproductive development. To clarify the mechanism of this phenomenon, further studies are under investigation.

The expression of Matrix metalloproteinase-2 and cyclooxygenase-2 by immunohistochemistry in patients with colorectal carcinoma

Background: Human colorectal carcinogenesis is a complex, multistep and multigenetic process. Matrix metalloproteinase-2 and cyclooxygenase-2 are key enzyme in degradation of extracellular material, are over expressed in several epithelia like colorectal adenocarcinoma.Objectives: This study was designed to detect the expression of matrix metalloproteinase-2 and cyclooxygenase-2 in patients with colorectal carcinoma and their correlation with age, gender, tumor grade and presence or absence of muscle invasion.Materials and methods: Immunohistochemical staining of MMP-2 and COX-2 was determined in 40 tissue samples from colorectal patients, from teaching laboratories in Baghdad medical city. In addition twelve apparently normal colorectal autopsies were used as a control group.Results: The expression of matrix metalloproteinase-2 was detected in 30 of 40 colorectal cancer cases (75%) while cyclooxygenase-2 was detected in 31 0f 40 colorectal cancer cases (77.5%). All normal colorectal specimens showed negative results. The incidence of both of them was higher for grade II than those in earlier grade.Conclusion: Cancer cells to have a more aggressive behavior may show an up regulation of tumor cell derived matrix metalloproteinase-2 and cyclooxygenase-2.

Expression of HuR, COX-2, and survivin in lung cancers; cytoplasmic HuR stabilizes cyclooxygenase-2 in squamous cell carcinomas

Hu antigen R (HuR) is a member of the human family of embryonic-lethal, abnormal vision-like proteins, which serves as an mRNA-binding protein. In the cytoplasm, HuR can stabilize the mRNA of cyclooxygenase-2 (COX-2), an enzyme that catalyses the synthesis of prostaglandins and is associated with promotion of carcinogenesis and tumor cell resistance to apoptosis. Intracellular (cytoplasmic and nuclear) localization of survivin has a prognostic significance as an apoptosis inhibitor and a regulator of cell division in tumors. Patients with 151 squamous cell carcinomas and 93 adenocarcinomas underwent lobectomy or pneumonectomy with hilar and mediastinal lymph node sampling. Paraffin-embedded tumor sections were retrieved for evaluation of nuclear and cytoplasmic staining of survivin and HuR, and cytoplasmic staining of COX-2. In squamous cell carcinomas, COX-2 expression was correlated with a difference of survivin (cytoplasmic−nuclear; P=0.004), cytoplasmic HuR (P=0.018), total HuR (cytoplasmic+nuclear; P=0.009), and difference of HuR (P=0.020). COX-2 was inversely correlated with nuclear survivin (P=0.006). In a univariate analysis by log-rank test, survival was associated with cytoplasmic survivin (adenocarcinoma, P<0.001; squamous cell carcinoma, P=0.005), difference of survivin (adenocarcinoma, P<0.001; squamous cell carcinoma, P=0.014), and COX-2 (squamous cell carcinoma, P=0.001). Survival was inversely associated with nuclear survivin (adenocarcinoma, P=0.006, squamous cell carcinoma, P=0.014). In a multivariate survival analysis, cytoplasmic survivin (adenocarcinoma, P=0.002; squamous cell carcinoma, P=0.015) and COX-2 (squamous cell carcinoma, P=0.020) were determined as independent prognostic factors. Cytoplasmic HuR expression is associated with COX-2 expression in squamous cell carcinomas. The expression of COX-2 in squamous cell carcinomas, and cytoplasmic survivin in adenocarcinomas and squamous cell carcinomas could be useful independent prognostic markers.

COX-2 and bcl-2 expression and clinical significance in patients with cystitis glandularis

Objective To determine the cyclooxygenase-2 (COX-2) and B-cell lymphoma-2 (bcl-2) expression and the clinical significance in tissue samples of patients with cystitis glandularis (CG). Methods Tissues from 131 patients, including 60 cases of CG, 11 cases of chronic cystitis (CC) and 60 cases of bladder transitional cell carcinoma (TCC) were obtained and immunohistochemical staining for COX-2 and bcl-2 was performed. Another 9 specimens of normal bladder epithelial tissue were also evaluated as controls. The changes of both COX-2 and bcl-2 expression before and after treatment were further studied. Results The COX-2 and bcl-2 expression in intestinal type of CG (CGIT) was higher than that in typical type of CG (CGTP), CC and control groups (P ＜0. 01 ). There were no significant differences in both COX-2 and bcl-2 expression between CGIT and TCC groups ( P ＞ 0. 05 ). The expression levels of COX-2 and bcl-2 in CG group were positively correlated as well as in TCC group (P ＜0. 01 ). The COX-2 and bcl-2 expression levels were reduced significantly after treatment (P ＜ 0. 01 ). Conclusion Although CG has the malignant potential, especially the intestinal type, transurethral electronresection combined with intravesical instillation of chemotherapeutics can reduce this risk. Key words: Cystitis glandularis ; COX-2 ; bcl-2 ; Instillation

Cyclooxygenase-2 Is an Independent Predictor of Poor Prognosis in Uterine Leiomyosarcomas

Cyclooxygenase-2 (COX-2) is a well-known enzyme that promotes tumor growth and metastasis. Cyclooxygenase-2 is upregulated in a number of human epithelial tumors, but data about the significance of COX-2 in mesenchymal tumors are lacking. The purpose of this study was to determine COX-2 expression in uterine sarcomas and whether a relationship exists between COX-2 expression and clinicopathologic outcomes. Immunohistochemical staining for COX-2 was performed on paraffin-embedded tissue blocks of 49 uterine sarcomas (30 leiomyosarcomas, 14 endometrial stromal sarcomas, and 5 carcinosarcomas). Positive staining was defined as moderate or strong staining in 5% or more of tumor cells. Four of 30 leiomyosarcomas, 1 of 14 endometrial stromal sarcomas, and 2 of 5 carcinosarcomas were positive for COX-2 expression. In leiomyosarcomas, COX-2 expression correlated with tumor stage with marginal significance (P = 0.058). Patients with leiomyosarcoma positive for COX-2 expression had a lower overall survival rate than those without COX-2 expression (P = 0.025). In the multivariate Cox proportional hazards regression model, COX-2 expression, tumor stage, and mitotic count were independently associated with overall survival in leiomyosarcomas. Our data suggest that immunohistochemically determined COX-2 expression is an independent prognostic factor in uterine leiomyosarcomas. Assessment of COX-2 status might be useful for determining the prognosis in patients with uterine leiomyosarcomas.