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.
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.
ObjectiveTo investigate the expression of cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) in human pancreatic adenocarcinoma and their correlation with clinicobiological behavior.MethodsThe expression of COX-2 and VEGF in 51 cases of human pancreatic ductal adenocarcinoma were detected with immunohistochemistry of Envision.ResultsExpression of COX-2 and VEGF in pancreatic ductal adenocarcinoma were 74.5% and 68.6%, respectively; no expression of COX-2 and VEGF in adjacent normal tissue was detected. Both COX-2 and VEGF expression in clinical stage Ⅲ-Ⅳ were much higher than those in clinical stage Ⅰ-Ⅱ, and also higher in positive group of lymph node metastasis than in negative group as well (Plt;0.05). None of them had relation with histological grades, age, sex, tumor size and location. The expression of COX-2 was closely correlated with VEGF (r=0.411, Plt;0.01).ConclusionCOX-2 and VEGF may play a pivotal role in tumorigenesis and tumor progression in pancreatic cancer, they may provide new targets for therapy of pancreatic cancer.
Objective To detect the expressions of epidermal growth factor receptor (EGFR), epidermal growth factor receptor-2 (C-erbB-2), vascular endothelial growth factor (VEGF) and cyclooxgenase-2 (COX-2) in gastric cancer tissues, and to analyze the relationship among them and the clinicopathologic factors of gastric cancer. Methods The SP immunohistochemical stain was used to detect EGFR, C-erbB-2, VEGF and COX-2 protein expressions in sample of 68 gastric cancer tissues. And their corresponding clinical data were analyzed retrospectively. Results The expression rates of EGFR, C-erbB-2, VEGF and COX-2 protein in gastric cancer tissue were 38.2% (26/68), 42.6% (29/68), 52.9% (36/68) and 60.3% (41/68) corresponding. An obvious increasing tendency as the differentiation of the cancer degraded, invasion depth deepened, lymphatic metastasis occurred and TNM stage upgraded was showed by the positive expression rates of them （P＜0.05，P＜0.01）; but there was no correlation with the patient’s sex, age, tumour site and size （Pgt;0.05）. There was a stable positive correlation among EGFR, C-erbB-2, VEGF and COX-2 expressions in gastric cancer tissue, respectively （P＜0.05）. Conclusion EGFR, C-erbB-2, VEGF and COX-2 expressions participate in the development, invasion and metastasis process of gastric cancer. Joint detection of them can be looked as an important symbol for judging the prognosis of gastric cancer and screening the high-risk metastasis patients, and guiding the molecular targeting therapy of gastric cancer.
【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.
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.
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.
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.