Chemically modified siRNAs and miRNAs bearing urea/thiourea-bridged aromatic compounds at their 3′-end for RNAi therapy

We have developed chemically modified siRNAs and miRNAs bearing urea/thiourea-bridged aromatic compounds at their 3′-end for RNAi therapy. Chemically modified RNAs possessing urea/thiourea-bridged aromatic compounds instead of naturally occurring dinucleotides at the 3′-overhang region were easily prepared in good yields and were more resistant to nucleolytic hydrolysis than unmodified RNA. siRNAs containing urea or thiourea derivatives showed the desired knockdown effect. Furthermore, modified miR-143 duplexes carrying the urea/thiourea compounds in the 3′-end of each strand were able to inhibit the growth of human bladder cancer T24 cells.     

高强度聚焦超声在药物控制释放的应用及进展

高强度聚焦超声能够以一种非侵入性的方式有效地穿透身体内部组织,聚焦在深层组织中一个很小的空间区域内,产生很强的声能,这些能量被组织吸收引起局部温度的升高。当温度到达热敏脂质体的相变温度时,磷脂烷基链构象的会发生改变,导致脂质体的通透性增强,从而能够促进药物的释放。因此,高强度聚焦超声可以被用作外源刺激控制体内特定位置热敏脂质体的药物释放。本文对高强度聚焦超声在药物控制释放领域的应用及进展进行综述。     

RNA干扰肝细胞肝癌中PECAM-1的表达对肿瘤细胞侵袭及增殖的影响

目的:探讨PECAM-1在肝细胞肝癌(Hepatocellular carcinoma,HCC)组织中的表达及意义。方法:选择2013年5月-2015年6月在我院接受治疗的HCC患者100例,收集肝癌患者HCC组织及癌旁组织,另选取100例正常肝脏组织作为对照组。应用免疫组织化学法检测PECAM-1在肝癌组织、癌旁组织以及正常肝脏组织中的阳性表达。利用小分子干扰RNA技术(si RNA)构建低表达的PECAM-1,并转染至肝癌细胞中抑制PECAM-1的表达。应用Transwell小室法检测肝癌细胞的侵袭能力,CCK-8法检测肝癌细胞的增殖能力。结果:PECAM-1在肝癌组织、癌旁组织及正常肝脏组织中呈不同程度阳性表达(P0.05);PECAM-1在肝癌组织及癌旁组织中的表达显著高于正常肝脏组织,差异具有统计学意义(P0.05);PECAM-1在肝癌组织中的表达显著高于癌旁组织,差异具有统计学意义(P0.05);转染si RNA PECAM-1后,肝癌细胞中PECAM-1 m RNA的表达水平明显下降,PECAM-1蛋白表达也明显降低,差异具有统计学意义(P0.05);转染si RNA PECAM-1后,肝癌细胞侵袭及增殖能力明显降低,差异具有统计学意义(P0.001)。结论:PECAM-1在肝癌患者血清中高表达,PECAM-1 si RNA能够抑制肝癌细胞的侵袭及增殖能力,提示PECAM-1可作为预测肝癌发生及发展的临床指标。