摘要：AIM： To study the effect of adenovirus （Ad）-p53 gene therapy on hepatocellular carcinoma （HCC） in a rabbit model.METHODS： VX2 tumor was grown in the liver of 24rabbits. Animals were divided into four groups： group A receiving trans-arterial gene therapy （Ad-p53） only,group B receiving combined Ad-p53 therapy and transarterial embolization （lipiodol）, group C receiving transarterial chemoembolization （lipiodol ＋ mitomycin C）,control group （D） receiving sodium chloride. Tumor volume （V1） was measured by using MRI （d 13）.Interventional procedure was applied （d 14）.Tumor volume （V2） was assessed by MRT （d 21） and the mean ratio （V2/V1） was calculated. After the second MRI,specimens of the liver were abstained and examined immunohistochemically using mutant-type p53 *** positive expression was scored.RESULTS： Compared with control group （（^-x） = 3.14± 0.64）, therapeutic groups all showed a significant decrease in the tumor growth ratio （P 〈 0.05）. A slight difference was found between group A （（^-x） =2.35 ±0.59） and group B （（^-x） = 1.75 ± 0.28） （P = 0.048）. Nostatistically significant difference was observed between group B and group C （（^-x） = 2.00 ± 0.44）. The positive expression rate of mutant-type p53 was the lowest in group B and significantly different between group A and group C （P 〈 0.05）.Compared to the control subjects, groups A and C both showed a decrease in the expression of mutant-type p53, but there was no significant difference between them.CONCLUSION： Trans-arterial Ad-p53 gene therapy can reduce tumor growth of HCC in rabbit model.

摘要：OBJECTIVE: To investigate the effects of anti-HPV16E6-ribozyme (HRz) on phenotype and gene expression of a cervical cancer cell line. METHODS: HRz was designed by computer programs. HRz's activity was identified by cleavage experiments in vitro. HRz and empty eukaryotic plasmids were transfected into CaSKi cells with lipofectin, then renamed CaSKi-R and CaSKi-P, respectively. The expression of ribozyme in transfected cells was observed by RNA dot blot. The amounts of E6 mRNA in three kinds of cells lines were detected by Northern blot. Cell growth curves and soft agar forming ability were studied. The ability of each cell line to form tumors was assessed in nude mice. Apoptosis rates and expression of c-myc, bcl-2, p53 and Fas were detected by flow cytometry (FCM). Antigens of tumor cells, HLA-1, HLA-2, B7-1 and B7-2 were also detected. NK, LAK, and CD(3)AK cells were induced. Their cytotoxicities were detected in CaSKi-R, CaSKi-P, and CaSKi cells. RESULTS: In vitro cleavage reaction demonstrated that HRz could cleave HPV16E6 mRNA in a site-specific manner. HRz could be expressed stably in transfected CaSKi cells. Northern blot analysis showed that E6 mRNA levels were lower in CaSKi-R than in CaSKi. The growth rate of CaSKi-R was slower than those of CaSKi and CaSKi-P. The soft agar-forming rate of CaSKi-R was lower compared with those of CaSKi and CaSKi-P cells. The ability of CaSKi-R to form tumors in nude mice was also poor. The apoptosis rate of CaSKi-R cells was much higher than those of CaSKi and CaSKi-P. HRz could reduce the expression of E6, c-myc and bcl-2 proteins, and increase the expression of p53 as well. HRz could increase the expression of HLA-2, B7-1 and B7-2 antigens. The cytotoxicity of NK, LAK and CD(3)AK cells was much higher in CaSKi-R than in CaSKi-P and CaSKi cells. CONCLUSION: HRz not only reverses the malignant phenotype of CaSKi cells partially, but also induces apoptosis in the cells, and increases sensitivity of CaSKi cells to immune cell

摘要：人类众多遗传性疾病是由于基因组突变所导致,而基于基因编辑技术的基因治疗策略,可从DNA层面对致病突变进行彻底修复,为疾病的治愈提供了新的可能.随着基因编辑技术的不断发展与突破,2019年新型DNA编辑工具先导编辑(PE)成功问世.PE技术并不会引起DNA双链断裂(DSBs),也无需单独引入DNA模板,即可实现基因编辑,可广泛应用于包括点突变及小片段的插入、删除等不同场景.与传统基因编辑工具相比,PE因其高编辑效率及低脱靶率,具备更高的有效性与安全性.本篇综述:(1)详细介绍了先导编辑的工作原理及发展历史.(2)概述了先导编辑系统的改良策略,包括相关酶的改造、工具RNA的结构改进以及递送方式的创新(3)梳理了辅助PE系统设计和分析的网页工具,简化了PE系统的搭建及使用流程.(4)系统总结了PE在疾病模型中的应用案例,并展望了未来的临床应用前景.

摘要：通过多重miRNA触发的原位siRNA递送治疗策略可以有效提高对癌细胞的精确治疗.基于DNA纳米结构的可编程性、特异性分子识别、易于功能化修饰和良好生物相容性的特点,我们设计了一个3D DNA纳米治疗平台,用于实现双miRNA触发响应的siRNA原位递送.这种3D DNA纳米结构(TY1Y2)是由DNA四面体支架、两组Y型DNA(Y1和Y2)和EpCAM核酸适体通过自组装构建而成的.TY1Y2被特异性内化至靶标癌细胞后,能够被两个内源性miRNA(miR-21和miR-122)触发,从而产生强的荧光共振能量转移信号,用于双miRNAs成像.同时,治疗性的siRNA(siSurvivin和siBcl2)也可以通过链置换反应从TY1Y2中产生并进行原位释放,实现癌细胞的协同基因治疗.这种3D DNA纳米结构将内源性生物标记物的特异性成像和治疗性基因的原位递送整合为一个多功能纳米平台,在癌症诊断和治疗方面显示出广阔的应用前景.