Kim Yun-Hee, Kim Kyung Tae, Lee Sang-Jin, Hong Seung-Hee, Moon Ju Young, Yoon Eun Kyung, Kim Sukyoung, Kim Eun Ok, Kang Se Hun, Kim Seok Ki, Choi Sun Il, Goh Sung Ho, Kim Daehong, Lee Seong-Wook, Ju Mi Ha, Jeong Jin Sook, Kim In-Hoo
1. Research Institute and hospital, National Cancer Center, Goyang 410-769, Republic of Korea; 2. Graduate School of Cancer Science & Policy, National Cancer Center, Goyang 410-769, Republic of Korea.
1. Research Institute and hospital, National Cancer Center, Goyang 410-769, Republic of Korea.
Theranostics. 2016 Jan 6;6(3):357-68. doi: 10.7150/thno.13621. eCollection 2016.
Trans-splicing ribozyme enables to sense and reprogram target RNA into therapeutic transgene and thereby becomes a good sensing device for detection of cancer cells, judging from transgene expression. Previously we proposed PEPCK-Rz-HSVtk (PRT), hTERT targeting trans-splicing ribozyme (Rz) driven by liver-specific promoter phosphoenolpyruvate carboxykinase (PEPCK) with downstream suicide gene, herpes simplex virus thymidine kinase (HSVtk) for hepatocellular carcinoma (HCC) gene therapy. Here, we describe success of a re-engineered adenoviral vector harboring PRT in obtaining greater antitumor activity with less off-target effect for clinical application as a theranostics. We introduced liver-selective apolipoprotein E (ApoE) enhancer to the distal region of PRT unit to augment activity and liver selectivity of PEPCK promoter, and achieved better transduction into liver cancer cells by replacement of serotype 35 fiber knob on additional E4orf1-4 deletion of E1&E3-deleted serotype 5 back bone. We demonstrated that our refined adenovirus harboring PEPCK/ApoE-Rz-HSVtk (Ad-PRT-E) achieved great anti-tumor efficacy and improved ability to specifically target HCC without damaging normal hepatocytes. We also showed noninvasive imaging modalities were successfully employed to monitor both how well a therapeutic gene (HSVtk) was expressed inside tumor and how effectively a gene therapy took an action in terms of tumor growth. Collectively, this study suggests that the advanced therapeutic adenoviruses Ad-PRT-E and its image-aided evaluation system may lead to the powerful strategy for successful clinical translation and the development of clinical protocols for HCC therapy.
反式剪接核酶能够感知靶RNA并将其重编程为治疗性转基因，从而根据转基因表达情况成为检测癌细胞的良好传感装置。此前我们提出了PEPCK-Rz-HSVtk（PRT），即由肝脏特异性启动子磷酸烯醇丙酮酸羧激酶（PEPCK）驱动的靶向人端粒酶逆转录酶（hTERT）的反式剪接核酶（Rz），其下游带有自杀基因单纯疱疹病毒胸苷激酶（HSVtk），用于肝细胞癌（HCC）的基因治疗。在此，我们描述了一种携带PRT的重新设计的腺病毒载体在获得更高抗肿瘤活性且脱靶效应更小方面取得的成功，可作为一种诊疗方法用于临床应用。我们将肝脏选择性载脂蛋白E（ApoE）增强子引入PRT单元的远端区域，以增强PEPCK启动子的活性和肝脏选择性，并通过在E1和E3缺失的5型血清型骨架的额外E4orf1-4缺失上替换35型纤维结，实现了对肝癌细胞更好的转导。我们证明，我们优化后的携带PEPCK/ApoE-Rz-HSVtk的腺病毒（Ad-PRT-E）实现了强大的抗肿瘤功效，并提高了特异性靶向HCC而不损伤正常肝细胞的能力。我们还表明，无创成像方式成功用于监测治疗性基因（HSVtk）在肿瘤内的表达情况以及基因治疗在肿瘤生长方面的作用效果。总体而言，这项研究表明，先进的治疗性腺病毒Ad-PRT-E及其图像辅助评估系统可能会成为成功临床转化以及制定HCC治疗临床方案的有力策略。
