氧合酶-2抑制剂celecoxib与喜树碱类衍生物联合用药的实验研究  

Effects of the combination of topoisomerase I inhibitors and celecoxib, a selective cylooxygenase-2 inhibitor on colorectal cancer

作　　者：付剑江[1] 李燕[1] 李洪燕[1] 刘悦[1] 陈晓光[1] 

机构地区：[1]中国医学科学院,中国协和医科大学药物研究所药理室,北京市100050

出　　处：《世界华人消化杂志》2005年第16期1985-1991,共7页World Chinese Journal of Digestology

摘　　要：目的:探讨喜树碱类衍生物与celecoxib联合用药的体外和体内的抗肿瘤作用及机制,同时观察celecoxib对CPT-11引起裸鼠腹泻的影响.方法:以MTT法检测结肠癌细胞系在联合应用celecoxib后对喜树碱及其衍生物的化学敏感性的改变;流式细胞术检测celecoxib与喜树碱联合用药后HT-29细胞的凋亡比率和细胞周期的变化;WesternBlot法检测环氧合酶-2(COX-2)以及凋亡相关蛋白(Bcl-2、Caspase-3、P53)的表达.以HT-29细胞裸鼠移植瘤模型观察celecoxib与CPT-11联合应用的体内抗肿瘤作用,并且观察Celecoxib对CPT-11引起腹泻及体重减轻的影响.结果:celecoxib可以显著降低三种喜树碱类衍生物对四种人结肠癌细胞系的IC50值,并且这种降低的程度与COX-2的表达密切相关.在HT-29细胞,celecoxib和CPT的联合应用使其凋亡率达到51.4%,而CPT单独使用的凋亡率为24.4%(P<0.01).同时,celecoxib可以使CPT处理组的G0/G1期细胞增加并降低S期和G2/M期的细胞比例(P<0.01).celecoxib和CPT的联合应用可以降低COX-2和Bcl-2的表达,增加Caspase-3和P53的表达.HT-29细胞裸鼠移植瘤实验中,celecoxib(60mg/kg)与CPT-11(25mg/kg)的联合应用使肿瘤生长明显抑制,其抑制率为78.77%(与对照组相比P<0.01),与CPT-11(25mg/kg)组相比也有显著差异(P<0.05).同时celecoxib(60mg/kg)可以明显减轻CPT-11引起腹泻症状,降低其腹泻评分(0.33±0.52vs2.33±0.82,P<0.01),并降低腹泻的发生率(16.67%vs83.33%,P<0.05);另外,celecoxib(60mg/kg)可以明显缓解CPT-11引起的裸鼠体重减轻(17.54±1.13gvs14.56±2.16g.P<0.05).结论:celecoxib可以增强CPTs的体外、内的抗肿瘤活性,这种作用可能与增加细胞凋亡和细胞周期阻滞作用有关.另外celecoxib可以减轻CPT-11引起的腹泻,并缓解CPT-11引起的体重下降.AIM： To investigate the antitumor properties of camptothecins （CPTs） combined with celecoxib, a selec- tive cylooxygenase-2 （COX-2）inhibitor, in vitro and in vivo, and the effects of celecoxib on idnotecan （CPT-11）-induced diarrhea in mice. METHODS： Four human colon cancer cell lines, HT-29, HCT- 8, HCT-116 and Caco-2 were exposed to the increasing concentrations （10-5, 10-4, 10^-3,10^-2, 10^-1, 1, 10,100μmol/L） of three topoisomerase I （Topo I） inhibitors, CPT-11, CPT and topotecan （TPT）, and celecoxib （1 and 5 μmol/L） as well as a combination of each Topo I inhibitor. Then MTr assay was performed to evaluate the effects of adjunct use of celecoxib on the chemosensitivity of colon cancer cells to CPTs. HT-29 cells were divided into control group, celecoxib treatment group, CPT treatment group and combined CPT with celecoxib treatment group. Flow cytometry was used to evaluate the apoptotic rates and cell cycle distribution. The expression of COX-2 and apoptosis-related proteins （Bcl-2, Caspase-3 and P53） were determined by immunocytochemical method. HT-29 cell line-xe-nografts model was established. The nude mice bearingtumor were divided into five groups, namely control group,CPT-11 （25 mg/kg per day） treatment group, celecoxib（60 mg/kg） treatment group and combined celecoxib （30mg/kg and 60 mg/kg, respectively） with CPT-11 treat-ment group. The effects of the drugs on tumor growth andthe severity of late diarrhea induced by CPT-11 wereassessed.RESULTS： Celecoxib significantly decreased the IC50 of the CPTs in the four colon cancer cell lines in vitro, but thereduction degrees of ICs0 depended on the level of COX-2 expression. In HT-29 cells, the apoptotic rates were51.4% in co-treated groups （24.4% in CPT treated groups,P〈0.01 ）, and the proportion in the G0/G1 phase were49.1% in co-treated group （5.5% in CPT treated groups,P〈0.01 ）. The expression of COX-2 and Bcl-2 were down-regulated, but the expression of P53 and Caspase-3 wereup-regulated aft

关 键 词：细胞凋亡 细胞周期 环氧合酶-2 拓扑异构酶I抑制剂 结肠癌 腹泻 CELECOXIB 喜树碱类衍生物 联合用药 环氧合酶 

分 类 号：R73-3[医药卫生—肿瘤]