Objective To investigate the effect of inducible nitric oxide synth ase (iNOS) or cyclooxygenase－2 (COX－2) on retinal neovascularization and its possible mechanism in oxygen－induced retinopathy （OIR） mouse model. Methods Retinal neovascularization was induced by oxygen with different concentration. The expression of iNOS, COX－2, matrix metalloproteinases 2 (MMP－2) and vascular end othelial growth factor (VEGF) in the retinae of experimental animals were analyzed by immunohistochemistry, realtime polymerase chain reaction and western blotting technologies. Results The inhibition of COX－2 or iNOS obviously attenuated retinal neovascularization and decreased the expression of VEGF and MMP－2. The iNOS inhibition decreased COX－2 expression, and vice versa. Conclusions COX－2 and iNOS may play a role in retinal neovascularization in OIR mouse model, which may act by regulating the expression of VEGF and MMP－2.
ObjectiveTo study the expressions of cyclooxygenase-2(COX-2) and Ki-67 in the invasive ductal carcinoma (IDC) of breast and to analyze its clinical significance.
MethodsImmunohistochemical SP method was performed to detect the expressions of COX-2 and Ki-67 in 82 cases of IDC of breast and corresponding tumor-adjacent normal breast tissues, and the relationship of these expressions to clinicopathologic characteristics was analyzed.
Results①The positive rates of COX-2 and Ki-67 protein expressions in the IDC of breast tissues were significantly higher than those in the corresponding tumor-adjacent normal breast tissue [COX-2:71.95%(59/82) versus 8.54%(7/82), χ2=68.56, P < 0.001;Ki-67:64.63%(53/82) versus 13.42%(11/82), χ2=45.20, P < 0.001].②The positive rates of COX-2 and Ki-67 protein expressions were positively correlated with TNM staging (COX-2:rs=0.349, P < 0.05;Ki-67:rs=0.305, P < 0.05), lymph node metastasis (COX-2:rs=0.336, P < 0.05;Ki-67:rs=0.419, P < 0.01), vascular invasion (COX-2:rs=0.235, P < 0.05;Ki-67:rs=0.461, P < 0.01), and histological grade (COX-2:rs=0.434, P < 0.01;Ki-67:rs=0.378, P < 0.05).The positive rate of Ki-67 protein expression was positively correlated with tumor diameter (rs=0.365, P < 0.01), but the positive rate of COX-2 protein expression wasn't correlated with it (rs=0.135, P > 0.05).The positive rates of COX-2 and Ki-67 protein expressions weren't correlated with menstrual status (COX-2:rs=0.172, P > 0.05;Ki-67:rs=0.163, P > 0.05).③The positive rate of COX expression was positively correlated with the positive rate of ki-67 expression (rs=0.475, P < 0.01).
ConclusionsThere are high-expressions of COX-2 and Ki-67 in IDC of breast.COX-2 and Ki-67 are significantly correlated with the clinicopathologic characteristics in IDC of breast.Combined detection of COX-2 and Ki-67 might calculate the biological behaviors of IDC of breast.COX-2 might be a target of molecular targeted therapy to breast cancer.
Objective To observe the inhibition effect of selective cyclooxygenase2 inhibitor（celecoxib）on the experimental choroidal neovascularization（CNV）. Methods Thirty 8-10 weeks old healthy male Brown-Norway（BN）rats were randomly divided into the control, laser and celecoxib group,with 10 rats in each group. At the dosage of 50 mg/kg, celecoxib was gavaged twice per day. After 7 days, experimental CNV was induced by Krypon laser on laser group and celecoxib group. Fundus fluorescein angiography (FFA) was performed on days 3, 7,14,21,30 after laser photocoagulation.On days 21 after photocoagulation, 5 rats in each group were sacrificed and the relative thickness of CNV membranes, the expression of COX-2, vascular endothelial growth factor(VEGF) and matrix metalloproteinase-2(MMP-2) were studied by histopathologic or immunohistochemistry examination.Results On days 21 after photocoagulation, the incidence of CNV in the celecoxib group is significantly lower than that in the laser group (chi;2=7.1068,P=0.0077); the relative thickness of the CNV membranes in the celecoxib group is reduced 41.38% compared to the laser group, the difference is statistically significant (t=16.760 0，P=0.0000).COX-2,VEGF and MMP-2 expression in the CNV membrane of celecoxib group were significantly lower than in control group (t=5.710 0,5.840 0, 8.020 0; P=0.000 0); the COX-2, VEGF and MMP-2 expressions in choroid and retina of control group were weak. Conclusion Prophylactic celecoxib can reduce the expression of VEGF and MMP-2 by inhibiting COX-2, and prevent the CNV induced by laser photocoagulation.
ObjectiveTo investigate the expression of keratinocyte growth factor (KGF) and cyclooxygen-ase-2 (COX-2) protein and microvessel density (MVD), and to explore their function and mechanism in the multistep process of gastric cancer. MethodsThe expressions of KGF and COX-2 protein in 64 samples of gastric cancer and 30 cases of normal gastric mucosa tissues were detected by immunohistochemistry. The MVD was detected by staining the endothelial cells in microvessles using anti-CD34 antibody. ResultsThe positive rate of KGF and COX-2 protein expression in gastric cancer were 65.6% (42/64) and 79.7% (51/64), respectively, which was significantly higher than that in normal gastric mucosa tissues 〔(23.3%, 7/30), P=0.046; (13.3%, 4/30), P=0.008〕. The MVD of gastric cancer was 31.8±8.0, which was significantly higher than that of normal gastric mucosa tissues (14.3±6.1), P=0.000. The MVD in gastric cancer with coexpressive KGF and COX-2 protein was 35.9±5.7, which was significant higher than that with non-coexpressive KGF and COX-2 protein (25.7±7.0), P=0.000. Both the expression of KGF and COX-2 protein were related to the invasion of serosa, lymph node metastasis and TNM staging (Plt;0.05, Plt;0.01). The MVD of gastric cancer tissues was related to lymph node metastasis and TNM staging (Plt;0.05), but unrelated to patient’s age, gender, and differentiation of tumor (Pgt;0.05). The co-expression of KGF and COX-2 protein was frequently found in patients with deeper invasion of serosa, lymph node metastasis, and higher TNM staging (Plt;0.05), but which was not associated withpatient’sage, gender, and differentiation of tumor (Pgt;0.05). The expression of KGF protein was positively correlated to the expression of COX-2 protein (r=0.610, P=0.000). There was positive correlation between MVD and the expression of KGF (r=0.675, P=0.000) and COX-2 protein (r=0.657, P=0.000) in gastric cancer, respectively. ConclusionKGF and COX-2 highly expressed by gastric cancer, which may be involved in the invasion and metastasis of gastric cancer by synergisticly promoting the angiogenesis.
Objective
To observe the effect of panretinal photocoagulation (PRP) on the expression of cyclooxygenase-2 (COX-2), vascular endothelial cell growth factor (VEGF) in epiretinal membrane of proliferative diabetic retinopathy (PDR).
Methods
Atotal of 35 patients (35 eyes) with PDR and underwent plana vitrectomy were enrolled in this study. The patients were divided into non-PRP group (19 patients, 19 eyes) and PRP group (16 patients, 16 eyes) depends on if they had received PRP before surgery. The epiretinal membranes stripped during operation were collected for pathological examination. The histopathological features was observed by haematoxylin and eosin stain. The expression of CD34, COX-2 and VEGF, and microvessel density (MVD) were measured by immunohistochemistry method.
Results
Many new dispersed capillary blood vessels were found in the thick epiretinal membranes of non-PRP group, while scattered small blood vessels were found in the relatively thin epiretinal membranes of PRP group. MVD value was (7.42±1.39) in the non-PRP group and (4.56±1.22) in the PRP group, which was lower than the non-PRP group (t=6.41, P<0.01). The expression of CD34, COX-2 and VEGF in the tissues of epiretinal membrane in PRP group were obviously lower than the non-PRP group (t=6.147, 5.944, 7.445; P<0.01).
Conclusion
PRP can effectively inhibit the expression of COX-2 and VEGF in epiretinal membrane of PRP patients.
【Abstract】Objective To investigate the relationship of expressions of cylooxygenase-2 (COX-2) and hypoxia-inducible factor-1α (HIF-1α) in hepatocelluar carcinoma (HCC) and the possible antineoplastic mechanism of selective COX-2 inhibitor. Methods The expressions of COX-2 and HIF-1α in 53 cases of HCC tissues were detected immunohistochemically. Western blot was employed to evaluate the effects of variant concentration of COX-2 inhibitor meloxicam on expression of HIF-1α in Cobaltchloridestimulated SMMC-7721 cell. ResultsOf 53 tumor tissues, the expression of COX-2 was 22/53 (41.5%) bly positive stained, 11/53 (20.8%) positive stained, and 20/53 (37.7%) negative stained. Meanwhile the expression of HIF-1α was 18/53 （34.0%） bly positive stained, 18/53 （34.0%）positive stained, 17/53（32.1%） negative stained. The expression of COX-2 was correlated positively with HIF-1α in HCC （r=0.440, P＜0.01）. The expression of HIF-1α increased sharply from 0.185±0.057 (no Cobaltchloride-stimulated) to 1.011±0.131 (Cobaltchloride-stimulated), and meloxicam could inhibit the expression of HIF-1α at either condition (P＜0.05). ConclusionMeloxicam could inhibit the expression of HIF-1α in a concentration-dependent manner in the Cobaltchloridestimulated SMMC-7721 cell. The antineoplastic activity of selective COX-2 inhibitor was possibly, at least in part, mediated by HIF-1α.
Objective To investigate the expression of cyclooxygenase-2 (COX-2) in liver tissue of severe acute pancreatitis (SAP) rats. Methods A rat model of SAP was induced by retrograde infusion of 3.5% sodium taurocholate into the biliary-pancreatic duct. Eighty rats were randomly divided into SAP group and control group. The levels of serum amylase (AMY), alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumor necrosis factor (TNF) -α and ascites AMY were detected dynamically at 4 h, 8 h, 16 h and 24 h after operation. The pancreatic and liver injuries were observed by light microscope. The expression of COX-2 in liver tissue was measured by immunohistochemistry. Results Compared with the control group, the levels of serum AMY, ALT, AST, TNF-α and ascites AMY increased significantly at the time point of 4 h, 8 h, 16 h and 24 h (Plt;0.05). These changes were paralleled with the histopathological changes of pancreatic and liver tissue. The expression positive rates of COX-2 at the different time in the SAP group were higer than those of the control group (Plt;0.05). There was a significantly positive correlation between the expression of COX-2 and ALT (rs=0.949, P=0.039), AST (rs=0.972, P=0.016) and serum AMY (rs=0.944, P=0.041), respectively. Conclusion Overexpression of COX-2 may play an important role in liver injury during SAP.
【Abstract】Objective To investigate the effects of selective cyclooxygenase-2 (COX-2) inhibitor nimesulide on the proliferation of colon adenocarcinoma cells in vitro and the expression of matrix metalloproteinase-2 (MMP-2). Methods The human colon cancer cell lines HT-29 and HCT-116 were employed in the study, grouped as nimesulide group, DMSO control group and blank control group. After treatment with nimesulide, the inhibitory effect of nimesulide on the proliferation of cancer cells was quantified by MTT assay, and the expression of MMP-2 in the cells was detected by quantitative zymography. Results Nimesulide inhibited the proliferation of HT-29 and HCT-116 cells in time and dosedependent manners. The inhibitory effect on HT-29 cells was ber than that on HCT-116 cells. Nimesulide downregulated the MMP-2 expression in HT-29 cells, whereas the expression in HCT-116 cells remained unchanged. Conclusion Nimesulide can obviously inhibit the growth of colon cancer HT-29 cells with positive COX-2 protein, suggesting that nimesulide may downregulate the expression of MMP-2 by inhibiting the activity of COX-2.
【Abstract】ObjectiveTo investigate the effects of nimesulide, a selective cyclooxygenase-2 (COX-2) inhibitor, on human cholangiocarcinoma QBC939 cell line in vitro. MethodsThe effects of nimesulide on QBC939 cells were observed with the following techniques: the influence of nimesulide on the proliferation of QBC939 cells was determined by MTT assay; the apoptosis of QBC939 cells was viewed and measured by transmission electron microscopy and flow cytometry, respectively; the expressions of proliferation cell nuclear antigen (PCNA) and COX-2 of cholangiocarcinoma cells were detected by immunocytochemistry. ResultsNimesulide inhibited the expressions of PCNA and COX-2 and the proliferation of cholangiocarcinoma QBC939 cells, whose effects intensified as the dose increased and time elongated. Flow cytometry showed that the apoptotic rates of QBC939 cells increased significantly as the dose of nimesulide increased. The typical morphologic features of apoptosis were also observed by transmission electron microscopy. ConclusionNimesulide significantly inhibits the proliferation of QBC939 cells in vitro by inducting cell apoptosis, which may be associated with the downregulation of COX-2 expression, and it also presents the features of dose and time dependents.
Objective To investigate the expression and clinical significance of cyclooxygenase-2 (COX-2) in human breast cancer with meta-analyses. Methods The published studies were searched in the CBM, CNKI, VIP and WanFang databases, and other relevant journals were also handsearched to identify all the relevant case-control trials. The quality of the included studies was assessed. The Cochrane Collaboration’s software RevMan 4.2.10 was used to test the heterogeneity, overall effect and publication bias of the combined studies. Results A total of 8 studies were recruited. As for the positive rate of COX-2 expression, significant differences were tested between breast cancer vs. normal breast tissues, cell differentiation G1 vs. cell differentiation G2-G3 with OR (95%CI) at 16.36 (9.18, 29.15) and 0.34 (0.18, 0.63), respectively. No significant difference was tested between lymph node metastasi vs. non-lymph node metastasi, clinical stages I-II vs. clinical stages III-IV with OR (95%CI) at 1.36 (0.61, 3.03) and 0.61 (0.34, 1.10), respectively. Conclusion According to the domestic evidence, COX-2 may be participated the whole course of carcinogenesis of breast cancer, but is not the absolute factor for estimating the survival rate of the patients with breast cancer, and more high-quality studies are expected for further study.
