【Abstract】 Objective To study the expressions of cyclooxygenase-2 (Cox-2) and angiopoietin-2 (Ang-2) in colorectal cancer tissues, cancer adjacent tissues and normal colorectal tissues, and the relationship between these expressions and the clinicopathologic features of colorectal cancer. Methods Forty-five excised samples of colorectal adenocarcinoma were confirmed pathologically and 39 of them were of well or moderately differentiated and 6 of poorly differentiated. Lymph nodes metastasis developed in 30 patients. And 15 cases were in stage of A or B and the rest were in the stage of C or D according to the Dukes stage. Taken PBS as the negative control and the verified Cox-2 or Ang-2 positive sections as positive controls, this study detected the expressions of Cox-2 and Ang-2 protein in 45 colorectal cancer tissues, 45 cancer adjacent tissues and 15 normal colorectal tissues by using immunohistochemical SP technique method. Results Cox-2 and Ang-2 were expressed in colorectal cancer tissues and cancer adjacent tissues, but were not expressed in normal colorectal tissues. In 45 colorectal cancer tissues, the positive expression rates of Cox-2 and Ang-2 were 80.0% and 66.7%; in 45 cancer adjacent tissues, the positive expression rates of Cox-2 and Ang-2 were 35.6% and 11.1%, respectively. The positive expression rates of both Cox-2 and Ang-2 in colorectal cancer tissues were significantly higher than those in cancer adjacent and normal colorectal tissues. There were close correlations between the expressions of Cox-2 and Ang-2 and some pathologic features, such as lymph node metastasis and Dukes stage; whereas there were no significant association between the expressions and gender, histological type and position of tumor. There was also a close correlation between the expressions of Cox-2 and Ang-2 themselves. Conclusion Cox-2 and Ang-2 play an important role in the occurrence and development of colorectal cancer. The use of specific inhibitor of Cox-2 as a treatment for colorectal cancer may become feasible and necessary.
ObjectiveTo explore the correlation between -765G/C polymorphism of cyclooxygenase-2 (COX-2) gene and the risk of ischemic stroke (IS). MethodsPubMed, CBM, The Cochrane Library (Issue 3, 2015), CNKI, CBM, VIP and WanFang Data were searched from inception to March 2015 to collect case-control or nested case-control studies about -765G/C polymorphism of COX-2 gene and the risk of IS. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then, meta-analysis was performed using RevMan 5.1 software and Stata 12.0 software. ResultsA total of 10 studies involving 2611 cases and 18589 controls were included. The results of meta-analysis showed that, there was no correlation between -765G/C polymorphism and the risk of IS (GC+CC vs. GG: OR=1.05, 95%CI 0.88 to 1.25, P=0.620; CC vs. GG+GC: OR=1.04, 95%CI 0.83 to 1.30, P=0.730; GC vs. GG: OR=1.04, 95%CI 0.87 to 1.25, P=0.630; CC vs. GG: OR=1.09, 95%CI 0.86 to 1.36, P=0.480; C vs. G: OR=1.03, 95%CI 0.89 to 1.20, P=0.700). Subgroup analysis results showed that, the COX-2 gene -765G/C polymorphism was a risk factor for IS in African-Americans (GC+CC vs. GG: OR=1.42, 95%CI 1.12 to 1.78, P=0.003; GC vs. GG: OR=1.39, 95%CI 1.09 to 1.78, P=0.008; CC vs. GG: OR=1.51, 95%CI 1.04 to 2.18, P=0.030; C vs. G: OR=1.27, 95%CI 1.08 to 1.51, P=0.004), but not in Asians and Caucasians. ConclusionCurrent evidence shows that -765G/C polymorphism of COX-2 gene may be a genetic risk factor for IS in African-Americans, but not in Asians and Caucasians. Due to the limited quantity and quality of the included studies, more high quality studies are needed to verify the above conclusion.
【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.
Objective To study the interaction and mechanism of prostaglandin I2 (PGI2) receptor/thromboxane A2 (TxA2) receptor (IP/TP) and cyclooxygenase-2 (COX-2) in ischemia reperfusion injury after liver transplantation of rat. Methods Rats were randomly divided into three groups: control group （n=16), orthotropic liver transplantation group （n=32) and nimesulide intervention group （n=32). The samples were obtained at 3 h, 6 h, 12 h and 24 h after operation. The expressions of COX-2, IP and TP mRNA were detected by RT-PCR. Immunohistochemistry was used to detect the localization and expression of COX-2. Hematoxylin Eosin staining was used to classify the injury extent of liver. Serum ALT and AST levels were detected to evaluate the changes of liver enzyme. Results COX-2 protein expression detected by immunohistochemistry in orthotropic liver transplantation group mainly distributed in the district of liver sinusoidal endothelial cells, liver cells and macrophage cells, which was significantly higher than control group and nimesulide intervention group. Expressions of IP mRNA, TP mRNA and COX-2 mRNA in the orthotropic liver transplantation group were significantly increased than those in control group (P＜0.05), and the ratio of IP/TP increased (P＜0.05). Expressions of IP mRNA and TP mRNA in nimesulide intervention group were significantly lower than that in the orthotropic liver transplantation group at 6 h and 12 h after operation (P＜0.05), and the ratio of IP/TP decreased at 3 h, 6 h and 24 h after operation (P＜0.05). The expression of COX-2 mRNA in nimesulide intervention group was significantly lower than that in the orthotropic liver transplantation group at 6 h, 12 h and 24 h after operation. In orthotropic liver transplantation group liver injury was obvious by HE staining, and more severve than that in nimesulide intervention group. Serum AST (each time) and ALT (3 h, 6 h and 12 h) levels in the orthotropic liver transplantation group were significantly higher than that in control group and nimesulide intervention group (P＜0.05) and peaked at 6 h after operation. Conclusion The balance of IP/TP takes part in and plays an important role in the ischemia reperfusion injury of liver transplantation. Changing imbalance of IP/TP may reduce liver transplantation ischemia reperfusion injury by inhibiting COX-2 expression.
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 observe the effect of lentivirus-mediated cyclooxygenase 2 (COX-2) and Aggrecanase-1 silencing and insulin-like growth factor 1 (IGF-1) in BMSCs after injecting into the knee joint cavity in cynomolgus monkeys with knee osteoarthritis (OA). MethodsBMSCs were isolated from the bone marrow of 10 donors. The lentivirus vector expressing genes of COX-2, Aggrecanase-1, and IGF-1 were constructed, and transfected into the third generation human BMSCs at 40 multiplicity of infection (virus group); BMSCs transfected with lentivirus-empty vector served as blank-virus group. The growth status and number of BMSCs were observed under inverted phase contrast microscope, and normal BMSCs were used as normal control group. At 1 week after transfected, the mRNA expressions of COX-2, Aggrecanase-1, and IGF-1 were detected with RT-PCR. Nine 3-year-old cynomolgus monkeys were selected to establish the OA model according to Hulth modeling method, and were randomly divided into 3 groups (n=3). At 6 weeks after remodeling, the right knee joint cavity was injected accordingly with 1 mL BMSCs (about 1×107 cells) in virus group and blank-virus group, with 1 mL of normal saline in the blank control group; the left knee served as normal controls. The general condition was observed after injection; at 1, 4, and 6 weeks, the concentrations of prostaglandin E2 (PGE2), IL-1, Aggrecanase-1, and IGF-1 of double knee liquid were detected with ELISA; at 6 weeks, MRI, general observation, histology method, and immunohistochemistry method were used to detect the knee cartilage changes and the expressions of COX-2, Aggrecanase-1, and IGF-1 were measured with RT-PCR. ResultsNo significant difference was found in cell morphology and growth curve between 2 groups after transfection. By RT-PCR, COX-2, and Aggrecanase-1 expressions were significantly reduced, IGF-1 expression was significantly increased in virus group when compared with normal control group and the blank-virus group (P < 0.05). All monkeys survived to the end of the experiment after injection. When compared with blank-virus group and blank control group, the concentrations of PGE2, Aggrecanase-1, and IL-1 significantly decreased and the concentration of IGF-1 significantly increased in the virus group (P < 0.05), but the indicators in 3 groups were significantly higher than those in the normal control group (P < 0.05). MRI showed that abnormal articular surface with high density could be found in virus group, blank-virus group, and blank control group, while the virus group had the minimum area. Gross observation and histological observation showed that the cartilage morphology of virus group, blank-virus group, and blank control group was accordance with early OA articular cartilage changes, but virus group was better than blank-virus group and blank control group in repair degree, whose improved Pineda score was significantly lower (P < 0.05). Immunohistochemical staining showed that the virus group had deeper dyeing with occasional brown particles and more chondrocytes than blank-virus group and blank control group. By RT-PCR, COX-2 and Aggrecanase-1 mRNA expressions of cartilage in virus group were significantly decreased, and IGF-1 expression was significantly increased when compared with blank control group and the blank-virus group (P < 0.05). ConclusionLentivirus-mediated multi-genes co-transfection in BMSCs can inhibit the expressions of COX-2 mRNA and Aggrecanase-1 mRNA, and enhance the IGF-1 mRNA expression, which decreases the concentration of inflammatory factors, and protects the joint cartilage effectively.
ObjectiveTo explore the expressions of prostaglandin F2α receptor (PTGFR) and cyclooxygenase-2 (COX-2) in tissues of benign bile duct scar and their significances, and investigate the regulating effect of transforming growth factor-β1 (TGF-β1) on the expression of PTGFR in human bile duct fibroblasts cultured in vitro. MethodsThe samples of common bile duct (CBD) scars were collected from 18 patients with benign bile duct scar stricture and 6 cases of normal CBD tissues from liver transplantation donor were collected as control. The expressions of PTGFR and COX-2 were detected by immunohistochemical strept-avidin-biotin complex (SABC) method. Semiquantitative RT-PCR and ELISA methods were used to detect the mRNA and protein levels of PTGFR in bile duct fibroblasts which were effected by TGF-β1 with different concentrations (0, 10, 20, and 30 ng/ml) for 24 h. ResultsThe positive rates of PTGFR and COX-2 were 88.9% (16/18) and 83.3% (15/18) in tissues of benigh CBD scar and 33.3% (2/6) and 0 (0/6) in normal CBD tissues (Plt;0.05). The expressions of the PTGFR mRNA and protein levels became upregulated when the concentrations of the TGF-β1 became higher in human bile duct fibroblasts (Plt;0.05). And the effect was concentration dependant to some extent. ConclusionsThe high expressions of PTGFR and COX-2 play important roles in the process of benign bile duct stricture formation. TGF-β1 is able to induce higher expressions of PTGFR mRNA level and the PTGFR protein level in a concentration dependent manner, and regulate the formation of benign bile duct stricture.
ObjectiveTo study the expression of cyclooxygenase2 (COX2) and its clinical significance in gastric carcinoma. MethodsThe expression of COX2 in 47 cases of gastric carcinoma and 16 cases of normal gastric tissue were detected by SP immunohistochemical technique. Helicobacter pylori (H.pylori) infection was diagnosed by urease experiment and Giemsa staining.ResultsThere was no positive signal of COX2 detected in normal gastric tissue. The positive expression rate of COX2 was 63.8%(30/47) in gastric carcinoma.The expression of COX2 was correlated with TNM stage, lymph node metastasis and H.pylori infection（P＜0.01）. Positive COX2 expression rate in H.pylori infection group was 72.4%(21/29), significantly higher than that in the group without H.pylori infection.Conclusion COX2 expression is involved in the carcinogenesis and malignant progression of gastric carcinoma.The examination of COX2 may be helpful to judge biological behavior of gastric carcinoma.
【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 effects of celecoxib-poly lactide-co-glycolide microparticles (CEL-PLGA-MS) on rat retina after intravitreal injection. Methods A total of 32 male Brown Norway rats were randomly divided into CEL-PLGA-MS group and celecoxib group, 16 rats in each group. The rats in CEL-PLGA-MS group were divided into four dosage group, four rats in each group, which received intravitreal injection of PLGA with celecoxib at the concentration of 40, 80, 160, 320 mu;mol/L, respectively. The rats in celecoxib group were divided into four dosage group, four rats in each group, which received intravitreal injection of celecoxib at the concentration of 40, 80, 160, 320 mu;mol/L, respectively. Phosphate buffer solution (PBS) was injected in two rats as PBS control group. Two rats as normal control group received no treatment. The difference of retinal thickness among groups was measured by optical coherence tomography (OCT). The morphological and histological change of retina was evaluated under light microscope and transmission electron microscope. Results There was no difference of retinal thickness between normal control group and PBS control group (F=0.12,P＞0.05). At the first week after injection, the retinal thickness of CEL-PLGA-MS group and celecoxib group were thicker than that in normal control group and PBS control group (F=9.62, 46.13;P＜0.01). The retinal thickness of celecoxib group was thicker than that in CEL-PLGA-MS group (F=165.15,P＜0.01). The retinal thickness was estimated equal among 40, 80, 320 mu;mol/L dosage groups in CEL-PLGA-MS group (F=4.79,P＜0.01). The retinal thickness of 160, 320 mu;mol/L dosage group were thicker than that in 40, 80 mu;mol/L dosage group in celecoxib group (F=28.10,P＜0.01). At the second week after injection, there was no difference of retinal thickness between CEL-PLGA-MS and celecoxib group (F=3.79,P＞0.05); the retinal thickness of CEL-PLGA-MS and celecoxib group became thinner gradually compare to the first week after injection (F=7.28, 103.99; P＜0.01). At the fourth week after injection, the retinal thickness of celecoxib group was thicker than that in CEL-PLGA-MS group (F=19.11,P＜0.01). The retinal thickness of CEL-PLGA-MS group was approximately the same to normal control group and PBS control group (F=2.02,P＞0.05). The retinal thickness of celecoxib group was thicker than that in normal control group and PBS control group. No considerable abnormality of the retina was seen by light microscope and the retinal thickness corresponded with the values measured by OCT at the first week after injection. The abnormal structures of the retina were seen in 160, 320 mu;mol/L dosage group of celecoxib group and inner changed evidently by the transmission electron microscope. Disordered arrangement of microfilaments, dilated microtubule and some mitochondria vacuolation were observed in 320mu;mol/L dosage group of celecoxib group. Others changed slightly. Conclusions CEL-PLGA-MS has less toxicity on the retina than free-celecoxib after intravitreal injection. The safety of intravitreal injection with CEL-PLGA-MS is better than celecoxib.