摘要
目的观察肿瘤靶向NGR/LPD复合物对人乳腺癌裸鼠移植瘤的抑制作用。方法抑瘤实验设有空白对照组、反义核酸组、正义NGR/LPD组、PEI/ASODN组、LPD组、NGR/LPD组。其中,PEI/ASODN组、LPD组及NGR/LPD3组分别设置高低浓度组(100μl,200μl)作对照考察剂量-效应相关性。通过激光共聚焦显微镜观察药物在裸鼠体内的分布情况。RT-PCR检测hTERTmRNA表达水平,免疫组化检测hTERT蛋白表达的变化。TUNEL法观察肿瘤细胞的凋亡情况。结果体内分布实验表明,NGR/LPD复合物具有肿瘤靶向性,未经NGR修饰的ASODN、LPD及PEI/ASODN则极少分布在肿瘤组织中。NGR/LPD组的瘤体生长最为缓慢,其最大抑瘤率与其他各组相比具有显著差异(P<0.05),hTERTmRNA和端粒酶活性表达明显低于各对照组(P<0.05),hTERT蛋白表达量下降,肿瘤细胞的凋亡指数明显高于各对照组(P<0.05)。结论 NGR/LPD在体内有很好的肿瘤靶向性和抑制肿瘤细胞生长的作用。
Objective To investigate the inhibitory effect of a novel non - viral gene delivery system, tumor - targeted gene delivery of Liposome - polycation - ASODN complexes（LPD） on telomerase in the MCF - 7 cells in vivo. Methods Human breast carcinoma cell line MCF -7 that grew logarithmically was traslplanted subcutaneously to BALB/C - nu/nu mice and model of xenoplanted tumor was established. 45 mice were divided randomly into 9 groups, including free ASODN group, blank control group, NGR/Lipo/PEI/SODN control group, Lipo/PEI/ASODN（ LPD ）group, NGR/Lipo/PEI/ASODN （NGR/LPD）group and PEI/ASODN group. The last three groups （LPD, NGR/LPD, PEI/ASODN）were divided into high and low doses （100μl,200μl） groups respectively in order to explore whether its efficiency of inhibiting tumor growth was correlated with dose. hTERT gene expression was detected by RT - PCR method, and hTERT protein was evaluated by immunohistochemistry. Apoptotic cells were evaluated with TUNEL assey. Distribution of drugs in nude mice was detected by laser eonfocal microscope. Results It was found that NGR/LPD could significantly inhibit tumor growth, compared with LPD, PEI/ASODN condensates and the negative control groups （P 〈 0.05）. The result from confocal microscope showed that NGR/LPD could be transported into tumor tissue efficiently after administering intravenously, while the condensates and unmodified LPD couldn＇t enter into tumor tissue efficiently. The expression of hTERT protein was decreased significantly （ P 〈 0.05 ）. The apoptosis index of the NGR/LPD group was obviously higher than that of the other groups （P 〈 0.05）. Conclusion NGR/LPD causes remarkable inhibitory effects on the growth of human breast carcinoma cell MCF - 7 in nude alice. The ideal tumor - target characteristic and strong anti - tumor activity of NGR/LPD were both proved in this study.
出处
《医学研究杂志》
2010年第8期30-34,141,共6页
Journal of Medical Research
基金
国家自然科学基金资助项目(90406024)
