摘要
背景与目的:华蟾素注射液是传统抗肿瘤中药制剂,目前药效机制尚不明确。本研究旨在探讨华蟾素注射液对DNA拓扑异构酶Ⅰ(topoisomerase Ⅰ,TOPOⅠ)的影响。方法:采用噻唑蓝还原法(MTT)观察华蟾素注射液对人肝癌HepG-2细胞增殖的影响;采用流式细胞术(FCM)检测对HepG-2细胞周期的影响;采用RT-PCR法检测对HepG-2细胞TOPOⅠmRNA表达的影响;采用TOPOⅠ介导的负超螺旋PBR322 DNA解旋反应检测华蟾素对TOPOⅠ酶活性的影响;采用负超螺旋PBR322 DNA检测华蟾素对DNA的直接抑制作用。结果:华蟾素注射液对HepG-2细胞增殖具有抑制作用,其抑制效应具有时间和剂量依赖性;并将HepG-2细胞阻滞于S期;RT-PCR检测表明,华蟾素注射液可下调TOPOⅠmRNA表达,表现浓度依赖效应;对TOPOⅠ介导的负超螺旋PBR322 DNA解旋反应有抑制作用;对负超螺旋PBR322 DNA没有直接抑制作用。结论:华蟾素注射液能够抑制HepG-2细胞增殖,影响DNA拓扑异构酶Ⅰ酶的mRNA表达及活性可能为机制之一。
Background and purpose:The cinobufacini injection is a traditional antitumor drug.However,its mechanism is still unclear.The purpose of this study was to observe the effect of cinobufacini injections in DNA TOPOⅠ of human hepatocellular carcinoma HepG-2 cells.Methods:The cells that were proliferated were assessed by MTT assay.Cell cycles were shown through FCM.TOPOⅠmRNA expression was analyzed through RT-PCR.The activity of TOPOⅠ was measured by TOPOⅠ mediated super coiled PBR322 relaxation.Supercoiled PBR322 was also used to determine the direct DNA breakages.Results:Cinobufacini injections significantly inhibited HepG-2 cells proliferation in ways that were dependent on dosages and time.Induced tumor cells arrest at the S-phase.TOPOⅠ mRNA expression decreased in a manner that was dependent on dosages which inhibited the TOPOⅠ mediated DNA relaxations.However,the cinobufacini injections could not directly induce DNA breakage at any concentration.Conclusion:Cinobufacini injections can inhibit human hepatocellular carcinoma HepG-2 cells proliferation.The regulation of topoisomerase Ⅰ activity and mRNA expression may be one of the mechanisms that causes the cinobufacini injection to contribute against tumor.
出处
《中国癌症杂志》
CAS
CSCD
北大核心
2010年第3期197-201,共5页
China Oncology