Gil-Farina Irene, Fronza Raffaele, Kaeppel Christine, Lopez-Franco Esperanza, Ferreira Valerie, D'Avola Delia, Benito Alberto, Prieto Jesus, Petry Harald, Gonzalez-Aseguinolaza Gloria, Schmidt Manfred
Department of Translational Oncology, National Center for Tumor Diseases and German Cancer Research Center, Heidelberg, Germany.
Department of Translational Oncology, National Center for Tumor Diseases and German Cancer Research Center, Heidelberg, Germany; Current address: Division of Applied Genomics, Eurofins Medigenomix GmbH, Ebersberg, Germany.
Mol Ther. 2016 Jun;24(6):1100-1105. doi: 10.1038/mt.2016.52. Epub 2016 Mar 7.
Recombinant adeno-associated viral vectors (rAAV) currently constitute a real therapeutic strategy for the sustained correction of diverse genetic conditions. Though a wealth of preclinical and clinical studies have been conducted with rAAV, the oncogenic potential of these vectors is still controversial, particularly when considering liver-directed gene therapy. Few preclinical studies and the recent discovery of incomplete wild-type AAV2 genomes integrated in human hepatocellular carcinoma biopsies have raised concerns on rAAV safety. In the present study, we have characterized the integration of both complete and partial rAAV2/5 genomes in nonhuman primate tissues and clinical liver biopsies from a trial aimed to treat acute intermittent porphyria. We applied a new multiplex linear amplification-mediated polymerase chain reaction (PCR) assay capable of detecting integration events that are originated throughout the rAAV genome. The integration rate was low both in nonhuman primates and patient's samples. Importantly, no integration clusters or events were found in genes previously reported to link rAAV integration with hepatocellular carcinoma development, thus showing the absence of genotoxicity of a systemically administered rAAV2/5 in a large animal model and in the clinical context.
重组腺相关病毒载体（rAAV）目前构成了一种用于持续纠正多种遗传疾病的切实可行的治疗策略。尽管已经对rAAV进行了大量临床前和临床研究，但这些载体的致癌潜力仍存在争议，尤其是在考虑肝脏靶向基因治疗时。很少有临床前研究以及最近在人类肝细胞癌活检中发现整合有不完整野生型AAV2基因组的情况，引发了对rAAV安全性的担忧。在本研究中，我们对来自一项旨在治疗急性间歇性卟啉症的试验中的非人类灵长类动物组织和临床肝脏活检样本中完整和部分rAAV2/5基因组的整合情况进行了表征。我们应用了一种新的多重线性扩增介导的聚合酶链反应（PCR）检测方法，该方法能够检测源自整个rAAV基因组的整合事件。在非人类灵长类动物和患者样本中的整合率都很低。重要的是，在先前报道的将rAAV整合与肝细胞癌发展联系起来的基因中未发现整合簇或整合事件，从而表明在大型动物模型和临床环境中全身给药的rAAV2/5没有遗传毒性。
