摘要
背景与目的:细胞间缝隙连接通讯(gapjunctionalintercellularcommunication,GJIC)是介导单纯疱疹病毒胸苷激酶(herpessimplixvirusthymidinekinase,HSV-tk)基因治疗中旁观者效应的重要机制。全反式维甲酸(all-trans-retinoticacid,ATRA)可能通过上调胶质瘤细胞GJIC和抑制肿瘤细胞生长的双重作用,促进HSV-tk基因治疗的疗效。本研究的目的在于证实HSV-tk和ATRA联合应用对胶质瘤细胞的协同杀伤作用。方法:分别以1μmol/L、10μmol/L、100μmol/L3种浓度的ATRA作用于培养的大鼠C6胶质瘤细胞,并研究ATRA对C6胶质瘤细胞分化、增殖、GJIC及connexin43(Cx43)基因转录等方面的影响。将C6细胞与稳定表达HSV-tk基因的C6tk细胞按不同比例混合,分别在含GCV和不同浓度ATRA或仅含GCV的培养基中培养,并于药物作用7天后用MTT法检测旁观者效应。结果:经3种浓度的ATRA作用后,C6胶质瘤细胞均显示出细胞分化的形态学特征。C6细胞的增殖也明显受到ATRA的抑制,绝大多数的活细胞都静止于G1期,100μmol/LATRA对C6细胞增殖的抑制尤其明显,并诱导细胞凋亡。经3种浓度的ATRA分别作用后,C6细胞的GJIC也明显提高,而Cx43基因的转录未受明显影响。旁观者效应实验的结果显示,3种浓度的ATRA均可以明显增强旁观者效应。
Background&Objective:Gap junctional intercellular commu nication(GJIC)is the main mechanism mediating the bystander effect in herpes simplex virus thymidine kinase(HSV-tk)gene therapy.All-trans retinoic ac id(ATRA)may augment the therapeutic efficacy of HSV-tk gene therapy by both upregulating GJIC in glioma cells and inhibiting tumor growth.This study was designed to investigate the synergistic effect of ATRA and HSV-tk gen e therapy in treatment of glioma.Methods:Rat C6glioma cells were exposed to ATRA at concentrations of 1μmol /L,10μmol /L,or 100μmol /L,respectively.The effects of ATRA on C6glioma cell differentiation,proliferation,G JIC,and connexin 43(Cx 43)gene transcription were studied.C6cells and C6tk cells,a stable transfectant of HSV-tk gene,mixed a t various ratios.The mixtures were t reated with GCV with ATRA at various concentrations or without ATRA,and the bystander effect was measured wi th MTT assay in 7days after treatment .Results:A morphological change of different iation was observed in C6glioma cells after exposure to each concentrati on of ATRA.The proliferation of C6cells was also significantly inhibited by ATRA,majo rity of living cells being arrested a t G1phase,especially at the concentration of 100μmol /L.At the concentration of 100μmol /L,ATRA also induced significan t apoptosis in C6glioma cells.The GJIC was significantly enhanced in C6ce lls after ARTA treatment at each concentration,while there was no ATRA induced effec t observed upon Cx43transcription.The results of bystander effect assa y revealed that ATRA at each concentration exerted a significant augmentation effect on bystander effect.Conclusion:The combination of two clinically safe protocols,ATRA and HSV-tk /GCV gene therapy,result ed in a synergistic effect in glioma t reatment,and would become a promising strategy fo r clinical administration.
出处
《癌症》
SCIE
CAS
CSCD
北大核心
2002年第5期473-479,共7页
Chinese Journal of Cancer
