Enhanced specificity of HPV16 E6E7 siRNA by RNA-DNA chimera modification.
Enhanced specificity of HPV16 E6E7 siRNA by RNA-DNA chimera modification.
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通过 RNA-DNA 嵌合修饰增强 HPV16 E6E7 siRNA 的特异性。
DOI：
10.1038/cgt.2011.28
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
Yamato K. et al.
中科院分区：
文献类型：
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作者：
Nguyen-T.;H. A.;Matsumoto;J.;and Endo;N.;Yushiro Fujii;Ohnuki S;Yamato K. et al.
尽管已经努力利用合成的小干扰RNA（siRNA）开发用于感染性和肿瘤性疾病的新药，但是这些药物固有地具有不期望的作用，包括非预期基因的沉默（脱靶效应）和非特异性细胞毒性。通过在引导链（GS）种子区的核苷酸位置1 - 8及其乘客链的互补部分加上3 ′突出端的DNA取代，可以避免脱靶效应，这被称为双链RNA-DNA嵌合体（dsRDC）。在这项研究中，我们发现，针对人乳头瘤病毒16型（HPV 16）E6和E7癌基因的有效siRNA的特异性，我们以前报道，可以通过短dsRDC修饰（GS 5 ′端的前6个核苷酸及其乘客链的互补核苷酸）增强。这种dsRDC修饰降低了三种siRNA中的两种（497和752）的非特异性细胞毒性，但另一种（573）则没有，这与它们的脱靶效应相关。此外，沉默活性在两个dsRDC（497和573）中轻微受损，在一个dsRDC（752）中中度受损。最后，dsRDC-497诱导宫颈癌细胞以及E6E7永生化的人角质形成细胞的E6E7特异性生长抑制。我们的结果表明，dsRDC修饰增强了E6E7 siRNA的特异性，这是在体内环境中使用所需的。
Although efforts have been made to develop new drugs for infectious and neoplastic diseases utilizing synthetic small interfering RNA (siRNAs), those intrinsically have undesirable effects, including silencing of unintended genes (off-target effect) and nonspecific cytotoxicity. Off-target effects can be avoided by DNA substitution in the guide strand (GS) seed region of nucleotide positions 1–8 and its complementary part of the passenger strand plus the 3′ overhang, which is designated as a double-strand RNA–DNA chimera (dsRDC). In this study, we found that the specificity of potent siRNAs targeting human papillomavirus 16 (HPV16) E6 and E7 oncogenes, which we previously reported, could be enhanced by short dsRDC modification (first six nucleotides from the 5′ end of the GS and its complementary nucleotides of the passenger strand). Such dsRDC modification reduced nonspecific cytotoxicity in two of three siRNAs (497 and 752), although not in the other (573), which correlated with their off-target effects. In addition, silencing activity was marginally impaired in two dsRDCs (497 and 573) and moderately in one (752). Finally, dsRDC-497 induced E6E7-specific growth suppression of cervical cancer cells as well as E6E7-immortalized human keratinocytes. Our results show that dsRDC modification enhances the specificity of E6E7 siRNA, which is required for use in in vivo settings.