Objective To summarize the research progress in antitumor mechanism of non-steroidal anti-inflam-matory drugs. Methods The domestic and international published literatures about antitumor mechanism of non-steroidal anti-inflammatory drugs in recent years were reviewed. Results The antitumor mechanism of non-steroidal anti-inflam-matory drugs was multistrata and multidigit. Conclusion Non-steroidal anti-inflammatory drugs can be used to prevent the development of colorectal cancer and also be a adjuvant therapy after radical operation for colorectal cancer.
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 evaluate the potential roles of celecoxib on proliferation and cell cycle progression of colon adenocarcinoma cells and on the hepatic metastasis of nude mice. Methods The human colon cancer cells HT-29 and HCT-116 were employed in the study. After treatment with celecoxib, the inhibitory effects of celecoxib on the proliferation of cancer cells were quantified by MTT assay, and the cell cycle progression was detected by flow cytometry, tumor cells were inoculated in nude mice, and the hepatic metastasis was detected. Results ①Celecoxib inhibited the proliferation of the tumor cells in time and dose-dependent manners （P＜0.05，P＜0.01）. The inhibitory effect on HT-29 cells was ber than that on HCT-116 cells （P＜0.05）. ②Celecoxib changed cell cycle progression of both kinds of cells, and decreased the proliferation index of both kinds of cells too. ③Celecoxib could inhibit the growth of the hepatic metastatic tumor obviously. Conclusion Celecoxib may inhibit the activity of cyclooxygenase-2, and resulting in the inhibition of division and proliferation, apoptosis of tumor cells and interfering in metastasis and relapse of colon cancer.
【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.
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.
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.
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.
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.
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.
Objective To observe the effect of celecoxib on the expression vascular endothelial growth factors (VEGF) in diabetic rats. Methods Thirty-six wistar rats were used to establish the diabetic models by intraperitoneal injection with streptozotocin. The diabetic rats were divided into 2 groups: diabetic group (n=18) and celecoxib group (n=18). Celecoxib (50 mg/kg) was administered orally to the rats in celecoxib group and the physiological saline with the same volume was given orally to the rats in diabetic group. Eighteen else rats were in normal control group. All of the rats were executed 3 months later. The expression of VEGF protein was detected by immunohistochemistry method. Reverse transcription-polymerase chain reaction（RT-PCR） analysis was used to examine the expression of retinal VEGF mRNA and cyclooxygenase-2 mRNA. Results Lower positive expression of VEGF mRNA and cyclooxygenase-2 mRNA, weakly positive action of immunohistochemistry of VEGF, and lower expression of VEGF protein were detected in normal control group; in the diabetic group, the expression of VEGF mRNA and cyclooxygenase-2 mRNA increased obviously comparing with which in the control group (Plt;0.05), and the bly positive action of immunohistochemistry of VEGF and increased expression of VEGF protein were detected (Plt;0.01); in celecoxib group, the expression of VEGF mRNA was lower than that in the diabetic group (Plt;0.05), the expression of cyclooxygenase-2 mRNA didnprime;t decrease much (Pgt;0.05), the positive action of immunohistochemistry of VEGF decreased, and the expression of VEGF protein decreased (Plt;0.01). Conclusion By inhibiting the activation of cyclooxygenase-2, celecoxib can inhibit the expression of retinal VEGF mRNA and protein in diabetic rats induced by streptozotocin. (Chin J Ocul Fundus Dis,2007,23:265-268)