塞来昔布对人骨肉瘤细胞株HOS-8603 P53表达的影响

目的:研究塞来昔布(Celecoxib)对人骨肉瘤细胞株HOS-8603 P53表达的影响,探讨其抗肿瘤作用机制。方法将培养HOS-8603细胞分为两组实验组(分别以20μmol/L和40μmol/L不同浓度塞来昔布处理)和对照组,采用RT-PCR检测各组的P53 mRNA表达。结果:20μmol/L塞来昔布组P53 mRNA的表达与对照组相比无差异(P>0.05);40μmol/L塞来昔布组P53mRNA表达与对照组相比有显著差异(P<0.05)。结论:塞来昔布可能通过促进人骨肉瘤细胞株HOS-8603 P53的表达发挥抗肿瘤作用。     

塞来昔布对肺癌的抑制作用机制研究

目的探讨环氧化酶抑制剂（COX-2）抑制剂塞来昔布对于A549肺癌细胞增殖及其小鼠移植瘤生长的抑制作用及可能机制。方法加不同浓度塞来昔布与A549肺癌细胞共培养,MTT法检测细胞增殖。流式细胞仪法检测细胞凋亡情况。A549细胞移植入BALB／c裸小鼠皮下后,随机分为实验组和对照组,实验组隔日腹腔注射塞来昔布30mg．kg^-1,对照组隔日腹腔注射等体积生理盐水,24d后处死移植瘤小鼠,计算抑瘤率,RT-PCR检测移植瘤组织中COX一2和VEGFmRNA表达水平,同时酶联免疫检测小鼠血清中MMP-9浓度,免疫组化检测瘤组织中微血管密度（MVD）。结果塞来昔布在体外对细胞株A549的生长抑制作用呈剂量、时间依赖性,且经塞来昔布作用后,A549细胞G0／G1期比例增加,S、G2／M期比例下降。在体实验显示,塞来昔布具有明显的抑制A549肺癌移植瘤增殖的作用,同时能抑制移植瘤组织中COX-2、VEGF表达,降低血清MMP-9浓度,减少移植瘤中微血管密度（P〈0．05）。结论塞来昔布在体内外均可显著抑制A549肺癌细胞的增殖,而诱导肿瘤细胞凋亡,抑制肿瘤血管生成和降低癌细胞侵袭能力是其可能的作用机制。     

塞来昔布对人肺癌A549细胞株增殖抑制和凋亡诱导作用观察

目的 体外研究选择性环氧化酶2 (COX-2)抑制剂塞来昔布对人肺癌细胞株A549增殖和凋亡的影响,并探讨其可能的作用机制.方法 采用噻唑蓝(MTT比色法)观察不同浓度的塞来昔布对人肺癌细胞株A549的增殖抑制作用,TUNEL染色检测细胞凋亡,并用含半胱氨酸的门冬氨酸蛋白水解酶-3(caspase-3)活性检测试剂盒检测其活性变化.结果 塞来昔布能够以浓度依赖性方式有效地抑制K562细胞增殖,药物的Ic50为33.98 μmol·L-1;TUNEL染色分析显示给予不同浓度塞来昔布的细胞与未给予塞来昔布的细胞相比凋亡率有差异(P＜0.05),经塞来昔布处理的A549细胞内caspase-3的A405较正常对照组有显著增加(P＜0.05).结论 塞来昔布能够抑制A549细胞增殖,并呈药物浓度依赖性;塞来昔布能以浓度依赖性方式诱导K562细胞凋亡,其机制涉及caspase-3活化的信号转导途径.     

3种选择性环氧合酶-2抑制剂对胰腺癌生长的影响

目的 比较3种不同选择性的环氧合酶-2(COX-2)抑制剂--美格昔康、塞来昔布、罗非昔布对人胰腺癌细胞生长及凋亡的影响，观察罗非昔布对人裸鼠胰腺癌移植瘤生长的抑制作用。方法采用3H-胞腺嘧啶核苷掺入，了解细胞DNA合成；用免疫组化检测增殖细胞核抗原(proliferating cell nuclear antigen，PCNA)及细胞COX-2的表达；用TUNEL染色法检测细胞凋亡。建立裸鼠胰腺癌移植瘤模型，给予罗非昔布8周，观察肿瘤大小、肿瘤组织的COX-2及PXNA的表达情况。结果 3种COX-2抑制剂均能抑制体外培养的胰腺癌细胞株BxPC-3的3H-胸腺嘧啶核苷掺入，其抑制效应与药物浓度呈显著正相关。COX-2抑制剂的选择性越高，对胰腺癌细胞生长的抑制作用越强。COX-2抑制剂均能诱导胰腺癌细胞的凋亡、降低胰腺癌细胞的COX-2、PCNA的表达。罗非昔布对裸鼠胰腺癌移植瘤的抑瘤率为87．7％；肿瘤组织的COX-2、PCNA表达均较对照组明显下降。结论 3种选择性COX-2抑制剂均能抑制人胰腺癌细胞的生长，并诱导其凋亡，对COX-2的选择性越高，对胰腺癌的抑制作用越强。罗非昔布可显著抑制裸鼠胰腺癌移植瘤的生长。     

塞来昔布对肝癌HepG2 HepG3细胞的免疫增敏作用

目的探讨选择性环氧合酶-2（COX-2）抑制剂塞来昔布（Celecoxib）对人肝癌HepG2和HepG3细胞株对肿瘤坏死因子相关的凋亡诱导配体（TRAIL）的增敏作用及其可能机制。方法以人HepG2 HepG3肝癌细胞为研究对象,以塞来昔布和TRAIL作为干预手段,采用四甲基偶氮唑蓝（MTT）法检测塞来昔布对肝癌细胞株的增殖抑制作用,采用流式细胞术,检测塞来昔布联合TRAIL对HepG2,HepG3细胞的凋亡及DR4,DR5的表达。塞来昔布与不同效靶比的细胞因子诱导的杀伤细胞（CIK）联合作用于人肝癌细胞株,经LDH检测法检测其杀伤作用。结果塞来昔布及TRAIL对人肝癌HepG2和HepG3细胞株均有显著抑制作用,塞来昔布联合TRAIL可显著增敏TRAIL对HepG2和HepG3的杀伤,其差异具有统计学意义（P〈0.05）,经过塞来昔布预处理的肝癌细胞更易被CIK细胞杀伤。结论塞来昔布对人肝癌HepG2和HepG3细胞株具有明显细胞毒性,联合TRAIL及CIK可显著增敏后者对肝癌细胞的杀伤效应,其机制可能与塞来昔布上调DR4,DR5有关。     

塞来昔布顺铂对卵巢癌细胞HO-8910增殖与凋亡影响的研究

目的探讨选择性环氧化酶(COX)-2抑制剂塞来昔布联合顺铂对人卵巢癌细胞株HO-8910增殖与凋亡的影响及Survivin、增殖细胞核抗原(PCNA)、COX-2蛋白表达情况。方法四甲基偶氮唑蓝(MTT)法测定不同浓度塞来昔布单用及其与顺铂联用时HO-8910细胞的增殖抑制率;流式细胞仪检测细胞周期及细胞凋亡率;免疫组织化学法检测Survivin、PCNA、COX-2蛋白的表达情况。采用方差分析和LSD-t检验进行统计分析。结果塞来昔布、顺铂均可抑制HO-8910细胞的生长(P<0.01);当两者合用时G0/G1期细胞增加,凋亡率增高更加明显(P<0.01),Survivin、PCNA、COX-2蛋白表达下调(P<0.01)。结论塞来昔布、顺铂对卵巢癌细胞株HO-8910均有抑制作用,塞来昔布能增强顺铂的抗卵巢癌作用。     

选择性COX-2抑制剂的心血管安全性评价

目的：研究以罗非昔布、塞来昔布、伐地昔布、鲁米昔布为代表的选择性COX-2抑制剂在临床应用的安全性。方法：查询国内外相关文献资料并结合临床实践进行回顾性研究。结果：罗非昔布、塞来昔布、伐地昔布、鲁米昔布等都有增加心血管不良事件的危险,同时罗非昔布的心血管风险要高于塞来昔布。结论：心血管危险是COX-2抑制剂的“类效应”,所以在临床应用这类药物时．应当加强合理的监管措施;仍需对COX-2抑制剂在心血管系统的安全性进行深入研究。     

塞来昔布对人乳腺癌SKBR-3细胞生长的影响

目的探讨选择性环氧化酶-2(COX-2)抑制剂塞来昔布对乳腺癌SKBR-3细胞生长的影响及机制。方法用不同浓度的塞来昔布处理SKBR-3细胞后,采用CCK-8法检测塞来昔布对SKBR-3细胞增殖活性的影响;流式细胞仪检测细胞周期;酶联免疫吸附试验(ELISA)检测前列腺素E2(PGE2)的释放水平;Western Blot法测定各浓度塞来昔布刺激SKBR-3细胞后Caspase-3被酶解激活情况。结果塞来昔布对SKBR-3细胞的增殖抑制作用呈剂量-时间依赖性;随着塞来昔布浓度的增加,G0/G1期细胞阻滞,S期细胞比例明显减少;塞来昔布明显减少PGE2的释放水平;Caspase-3在细胞凋亡早期被激活,在凋亡晚期则无表达。结论塞来昔布能有效抑制乳腺癌SKBR-3细胞的增殖,诱导其凋亡;其作用机制可能与COX-2表达下调、抑制PGE2水平和促进Caspase-3的活化有关。     

塞来昔布联合PDTC对人胃癌细胞株SGC-7901生长的抑制作用

目的:研究塞来昔布及吡咯烷二硫氨基甲酸(PDTC)对人胃癌细胞株SGC-7901的生长抑制作用及其相关机制。方法:分别应用塞来昔布50、100μmol/L,PDTC50、100μmol/L及2药联合25/25、50/50μmol/L处理SGC-7901胃癌细胞,四甲基偶氮唑蓝(MTT)法检测细胞生长抑制率。TUNEL法检测细胞的原位凋亡。RT-PCR检测环氧合酶-2(COX-2)、核因子(NF)-κB、caspase-3mRNA的表达。结果:塞来昔布、PDTC及2药联合作用于胃癌细胞72h细胞的生长均受到抑制(P<0.05),72h时25/25μmol/L的2药联合组与50μmol/L塞来昔布组相比,细胞的生长抑制率无明显差异(P>0.05),50/50μmol/L的2药联合组细胞生长抑制率高于100μmol/L的单独用药组(P<0.01)。100μmol/L的单独用药组和50/50μmol/L的2药联合组在作用于细胞24h后,细胞凋亡指数均高于阴性对照组,且2药联合组凋亡指数高于单独用药组(P<0.01)。100μmol/L的塞来昔布及PDTC单独作用于细胞12h后均可见COX-2、NF-κB表达降低(P<0.05),100μmol/L的塞来昔布和PDTC及2种浓度的2药联合caspase-3表达升高(P<0.05)。结论:塞来昔布与PDTC联合应用具有显著抗胃癌细胞增殖,促进其凋亡的作用,其机制可能与抑制COX-2、NF-κB的表达,促进caspase-3表达有关。     

昔布类药物的临床安全性

昔布类药物即高选择性COX-2抑制剂,通过选择性抑制COX-2,阻断花生四烯酸合成前列腺素而发挥抗炎镇痛作用,可减少传统NSAID药物消化系统的不良反应,主要品种有罗非昔布、塞来昔布、伐地昔布、帕瑞昔布、依托昔布及卢米昔布等。其中罗非昔布(万络)在2004年9月由于心血管不良反     

Effects of the selective COX-2 inhibitors celecoxib and rofecoxib on human vascular cells

Rheumatoid arthritis (RA) is associated with a reduced life expectancy considered to be partly caused by cardiovascular events. A growing concern is that accelerated atherosclerosis is driven by inflammatory mechanisms similar to those responsible for RA. Therefore, selective COX-2 inhibitors, which are widely used for the symptomatic treatment of pain and inflammation in RA, may have an impact on atherosclerotic processes. Their anti-inflammatory properties might provoke anti-atherogenic effects but on the other hand, selective inhibition of anti-thrombotic prostacyclin and COX-2 independent effects might promote the risk of increased prothrombotic activity. In the current study, the effects of the presently marketed selective COX-2 inhibitors celecoxib and rofecoxib on vascular cells have been investigated. Celecoxib inhibited the proliferation of human umbilical vein endothelial cells (HUVECs) in a concentration-dependent manner. At high concentrations, it induced apoptosis and the modulation of inhibitory cell cycle proteins. In contrast rofecoxib-even at high concentrations-had no effect on cell proliferation, apoptosis or cell cycle distribution indicating that celecoxib and rofecoxib do not affect the same signal transduction pathways in endothelial cells. Both drugs did not affect apoptosis induction or cell cycle proliferation in human vascular smooth muscle cells. The observed effects on endothelial cells appear to be COX-independent since both drugs selectively inhibited COX-2-activity and the applied concentrations lay beyond the IC(50) for inhibition of prostacyclin production. Regarding endothelial apoptosis as a relevant event in the initiation and progression of atherosclerosis the present data put forward the hypothesis that the presently marketed COX-2 inhibitors have a different impact on atherosclerotic processes.     

The anti-proliferative potency of celecoxib is not a class effect of coxibs

Celecoxib, a COX-2 (cyclooxygenase-2)-selective inhibitor (coxib), is the only NSAID (non-steroidal anti-inflammatory drug) that has been approved for adjuvant treatment of patients with familial adenomatous polyposis. To investigate if the anti-proliferative effect of celecoxib extends to other coxibs, we compared the anti-proliferative potency of all coxibs currently available (celecoxib, rofecoxib, etoricoxib, valdecoxib, lumiracoxib). Additionally, we used methylcelecoxib (DMC), a close structural analogue of celecoxib lacking COX-2-inhibitory activity. Due to the fact that COX-2 inhibition is the main characteristic of these substances (with exception of methylcelecoxib), we conducted all experiments in COX-2-overexpressing (HCA-7) and COX-2-negative (HCT-116) human colon cancer cells, in order to elucidate whether the observed effects after coxib treatment depend on COX-2 inhibition. Cell survival was assessed using the WST proliferation assay. Apoptosis and cell cycle arrest were determined using flow cytometric and Western blot analysis. The in vitro results were confirmed in vivo using the nude mouse model. Among all coxibs tested, only celecoxib and methylcelecoxib decreased cell survival by induction of cell cycle arrest and apoptosis and reduced the growth of tumor xenografts in nude mice. None of the other coxibs (rofecoxib, etoricoxib, valdecoxib, lumiracoxib) produced anti-proliferative effects, indicating the lack of a class effect and of a role for COX-2. Our data emphasize again the outstanding anti-proliferative activity of celecoxib and its close structural analogue methylcelecoxib in colon carcinoma models in vitro and in vivo.     

Gastroduodenal safety of cyclooxygenase-2 inhibitors

Cyclooxygenase-1 (COX-1) derived eicosanoids promote gastroprotective mucosal defenses and induce platelet aggregation. By sparing COX-1, COX-2 specific inhibitors provide effective anti-inflammatory and analgesic activity while substantially reducing the risk of peptic ulcer disease and GI bleeding compared to dual COX inhibitors (traditional NSAIDs). Clinical studies of the COX-2-selective inhibitors have demonstrated efficacy equivalent to nonselective NSAIDs with significantly lower rates of GI toxicity. The incidence of endoscopic ulcers in some studies with coxibs has approximated placebo. However, as the detection of endoscopic lesions is not always correlated with symptomatic ulcers and ulcer complications, outcome studies of GI safety were performed. The results of large outcome studies have evaluated rofecoxib and celecoxib in over 39,000 patients with osteoarthritis or rheumatoid arthritis. Results of these studies showed that patients taking a supratherapeutic dose of rofecoxib or celecoxib had significantly lower rates of GI-related adverse events than those taking a nonselective NSAID. The GI safety of coxibs for patients using low dose aspirin concomitantly with a coxib appears to be reduced, particularly with regard to ulcer complications. Such data provide support for the COX-2 hypothesis and demonstrate that coxibs provide effective treatment of pain and inflammation with a reduced risk of gastropathy.     

Biology of Cox-2: an application in cancer therapeutics

Cyclooxygenase-2 (Cox-2) is an inducible enzyme involved in the conversion of arachidonic acid to prostaglandin and other eicosanoids. Molecular pathology studies have revealed that Cox-2 is over-expressed in cancer and stroma cells during tumor progression, and anti-cancer chemo-radiotherapies induce expression of Cox-2 in cancer cells. Elevated tumor Cox-2 is associated with increased angiogenesis, tumor invasion and promotion of tumor cell resistance to apoptosis. Several experimental and clinical studies have established potent anti-cancer activity of NSAID (Non-steroidal anti-inflammatory drugs) and other Cox-2 inhibitors such as celecoxib. Much attention is being focused on Cox-2 inhibitors as beneficial target for cancer chemotherapy. The mode of action of Cox-2 and its inhibitors remains unclear. Further clinical application needs to be investigated for comprehending Cox-2 biological functions and establishing it as an effective target in cancer therapy.     

Role of COX-2 selective inhibitors for prevention and treatment of cancer

Cyclooxygenase-2 (COX-2) is an enzyme induced by inflammatory and mitogenic stimuli and results in enhanced synthesis of PGs in inflamed and neoplastic tissues. It is associated with cell proliferation and growth, in various cancerous conditions. We review the potential mechanisms of cancer reduction with COX-2 inhibitors and the preclinical evidence suggesting their effectiveness. Results of our study show that COX-2 is a regulatory factor for a number of pathways that can result in cancer. COX-2 makes cells resistant to apoptosis and promote angiogenesis, metastasis and cancer cell cycle by controlling number of targets. We found that, COX-2 selective inhibitors (like celecoxib and NS-398) can suppress the cancer both by COX-2 dependent and COX-2 independent pathways. COX-2 inhibitors can also produce synergic effects when used with other anti-cancer therapies. Thus, it is concluded that COX-2 selective inhibitors may be promising agents for prevention and treatment of cancer.     

Drug switching patterns among patients with rheumatoid arthritis and osteoarthritis using COX-2 specific inhibitors and non-specific NSAIDs

PURPOSE: To compare RA and OA patients' time-to-switch after newly initiating treatment with three most commonly used non-specific (NS)-NSAIDs and two COX-2 inhibitors, celecoxib and rofecoxib. METHODS: Managed care enrollees newly prescribed celecoxib, rofecoxib, ibuprofen, naproxen or diclofenac were identified. Time to switch to a different NS-NSAID or COX-2 specific inhibitor was determined using time-to-event analysis and Cox proportional hazards models were used to estimate the odds ratio (OR) after controlling for potential confounders. RESULTS: The time to 25% of the cohort switching was longer for rofecoxib and celecoxib (159 and 205 days respectively) compared to the three NS-NSAIDs (49-78 days). Patients were at the highest risk of switching within the first 100 days of therapy. After adjusting for potential confounding factors, the OR for switching to another NS-NSAID or COX-2 specific inhibitor ranged from 1.74 to 2.35 for the three NS-NSAIDs compared to celecoxib (all comparisons, p < 0.01). Similar findings were obtained when comparing rofecoxib to each of the three NS-NSAIDS (all comparisons, p < 0.01). When COX-2 inhibitors combined were compared to NS-NSAIDS combined, the OR for switching was 1.53 (95% confidence interval = 1.42-1.65; p < 0.01) after adjusting for potential confounders. CONCLUSIONS: Patients on the COX-2 specific inhibitors (celecoxib and rofecoxib) were significantly less likely to switch their therapy than patients on NS-NSAIDS (ibuprofen, naproxen and diclofenac). These results suggest that COX-2 specific inhibitors may be a more effective treatment option when compared with NS-NSAIDs in usual clinical practice.     

Interaction of celecoxib with different anti-cancer drugs is antagonistic in breast but not in other cancer cells

Celecoxib, an inhibitor of cyclooxygenase-2, is being investigated for enhancement of chemotherapy efficacy in cancer clinical trials. This study investigates the ability of cyclooxygenase-2 inhibitors to sensitize cells from different origins to several chemotherapeutic agents. The effect of the drug's mechanism of action and sequence of administration are also investigated.The sensitivity, cell cycle, apoptosis and DNA damage of five different cancer cell lines (HeLa, HCT116, HepG2, MCF7 and U251) to 5-FU, cisplatin, doxorubicin and etoposide ± celecoxib following different incubation schedules were analyzed.We found antagonism between celecoxib and the four drugs in the breast cancer cells MCF7 following all incubation schedules and between celecoxib and doxorubicin in all cell lines except for two combinations in HCT116 cells. Celecoxib with the other three drugs in the remaining four cell lines resulted in variable interactions.Mechanistic investigations revealed that celecoxib exerts different molecular effects in different cells. In some lines, it abrogates the drug-induced G2/M arrest enhancing pre-mature entry into mitosis with damaged DNA thus increasing apoptosis and resulting in synergism. In other cells, it enhances drug-induced G2/M arrest allowing time to repair drug-induced DNA damage before entry into mitosis and decreasing cell death resulting in antagonism. In some synergistic combinations, celecoxib-induced abrogation of G2/M arrest was not associated with apoptosis but permanent arrest in G1 phase.These results, if confirmed in-vivo, indicate that celecoxib is not a suitable chemosensitizer for breast cancer or with doxorubicin for other cancers. Moreover, combination of celecoxib with other drugs should be tailored to the tumor type, drug and administration schedule.     

塞来昔布联合维甲酸对SW620细胞增殖和凋亡的影响

目的:探讨塞来昔布联合全反式维甲酸抑制结肠癌SW620细胞增殖和促进凋亡的作用及机制。方法:不同浓度塞来昔布和全反式维甲酸作用SW620细胞48或72 h后应用MTT法和流式细胞仪分别检测细胞的增殖抑制和凋亡率,Western Blot检测细胞AKT、p-AKT及survivin的表达。结果:与单药作用相比,塞来昔布和全反式维甲酸联合作用可明显增强对SW620的增殖抑制和促进凋亡作用(P均<0.01)。Western Blot提示全反式维甲酸和塞来昔布联合作用SW620细胞可抑制AKT活性,下调p-AKT和survivin蛋白表达。结论:塞来昔布在抑制结直肠癌细胞增殖和促进其凋亡中与全反式维甲酸起协同作用,抑制AKT磷酸化、阻断PI3K/Akt通路和下调survivin是其可能作用机制。此结果有望为临床提供可行的联合用药方案,推广维甲酸的诱导分化和凋亡治疗。