嵌合型E1B55-kDa蛋白缺陷型腺病毒载体治疗肿瘤的评价(英文)

Assessment of a Capsid-modified E1B 55-kDa Protein-deficient Adenovirus Vector for Tumor Treatment

ONYX-015和H101为可复制E1B55-kDa蛋白缺陷的C族腺病毒,它们正作为抗癌药物进行临床研究.然而它们在癌症基因治疗中的应用却受到了C族腺病毒天然特性的制约,部分原因是由于在恶性肿瘤中C族腺病毒受体(coxsackievirus-adenovirusreceptor,CAR)的表达量较低.构建了一个以H101为骨架的含有编码35型腺病毒鞭毛区域的基因,替代5型腺病毒鞭毛基因的嵌合型腺病毒载体.这一改动使得腺病毒载体可以通过一种在肿瘤中高表达的膜蛋白CD46感染肿瘤细胞.应用RT-PCR方法检测不同肿瘤细胞株中CAR和CD46表达量的区别.在CAR受体低表达的细胞株中(MDA-MB-435和MCF-7),H101-F35表现出比H101和ONYX-015更强的细胞杀伤效果;在CAR受体高表达的细胞株中(A549,NCI-H446,Hep3B,LNCaP,ZR-75-30和Bcap-37),H101-F35、H101和ONYX-015的细胞杀伤效果则相似.在荷MDA-MB-435肿瘤的裸鼠模型中,注射H101-F35的抑瘤效果比注射H101的抑瘤效果更明显.这些结果表明嵌合型溶瘤腺病毒载体H101-F35在肿瘤基因治疗中将有很好的应用前景.

ONYX-015 and H101 are E1B 55-kDa protein-deficient replicating C group adenoviruses that are currently in clinical trials as antitumor agents. However, their application in cancer gene therapy is limited by the native tropism of C group adenoviruses. This is in part due to low expression of the C group adenovirus receptor （coxsackievirus-adenovirus receptor, CAR） on malignant tumors. An H 101-based chimeric virus vector containing sequences encoding the Ad35 fiber domain instead of the Ad5 fiber （H 101-F35） was constructed. This modification allowed infection of tumor cells through CD46, a membrane protein over-expressed on tumors. The CAR and CD46 RNA expression was evaluated by RT-PCR method. H101-F35 conferred a stronger cytocidal effect than H101 and ONYX-015 in tumor cell lines that lacked CAR expression （MDA-MB-435 and MCF-7）, while the cytocidal effect of H101-35, HI01 and ONYX-015 was similar in high-level CAR expressing cancer cell lines （A549, NCI-H446, Hep3B, LNCaP, ZR-75-30 and Bcap-37）. In an MDA-MB-435 xenografl mouse tumor model, tumor growth in mice receiving H101-F35 was significantly inhibited compared with mice injected with H101. These results suggest that the chimeric oncolytic adenovirus H101-F35 vector might be a useful candidate for gene therapy of cancer.