摘要
司莫司汀是重要的抗癌烷化剂,其抗癌机制与导致DNA股间交联有关。使用荧光法和高效液相色谱-电喷雾串联质谱联用(HPLC-ESI-MS/MS)法对司莫司汀导致的λDNA交联率进行了测定。结果表明:药物浓度为2,4,8和16 mmol/L时,荧光方法测得的最大交联率分别为8.81%,11.17%,17.61%,和23.39%;HPLC-ESI-MS/MS方法测得的最大交联率为每107个碱基对中分别含有138,256,378和433个dG-dC交联。通过比较,荧光法测得的是交联DNA双链的含量,而HPLC-ESI-MS/MS法测得的是实际交联碱基对的个数,后者更能从本质上揭示交联率的变化规律。两种方法均表明交联反应初期存在一段交联率上升缓慢的"诱导期",这为阐明交联机理提供了依据。
Semustine（Me-CCNU） is an important alkylating agent used in the clinical treatment of cancer.The anticancer mechanism of Me-CCNU is associated with the formation of DNA interstrand crosslinks（ICLs）.In this study,the ICLs induced by Me-CCNU were investigated using fluorescent assay and high performance liquid chromatography-electronspray ionization-tandem mass spectrometry（HPLC-ESI-MS/MS）.The results showed that the maximum of the crosslinking factor（CF） obtained from fluorescent assay was 8.81%,11.17%,17.61% and 23.39%,respectively,with the concentration of Me-CCNU of 2,4,8 and 16 mmol/L;the maximum of the CF obtained from HPLC-ESI-MS/MS was 138,256,378 and 433 crosslinked dG-dCs per 107 base pairs,respectively,with the concentration of Me-CCNU of 2,4,8 and 16 mmol/L.By comparing these two methods for the determination of DNA interstrand crosslinks,the CF obtained from fluorescent assay characterized the crosslinks of the DNA double strands;on the other hand,the CF obtained from HPLC-ESI-MS/MS characterized the content of the crosslinked dG-dC.The latter gave a more essential quantification of the ICLs than the former.An ＂induction phase＂ was found by both of the two methods,in which the CF increased slowly during the beginning period of the reaction.This result provided evidences for the clarifing of the mechanism of the formation of ICLs.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
2011年第4期476-480,共5页
Chinese Journal of Analytical Chemistry
基金
国家自然科学基金(No.20907002)
北京市科技新星(No.2009B08)
北京市优秀人才培养(No.20081A0501500179)资助项目
关键词
氯乙基亚硝基脲
DNA股间交联
荧光
高效液相色谱-电喷雾串联质谱
司莫司汀
Chloroethylnitrosoureas
Deoxyribonucleic acid interstrand crosslinks
Fluorescence
High performance liquid chromatography-electrosprary ionization-tandem mass spectrometry
Senustine
