Division of Orthopedic Surgery, Graduate School of Medical and Dental Sciences, Niigata University, 1-757 Asahimachi-dori, Chuo-ku, Niigata 951-8510, Japan.
J Cancer Res Clin Oncol. 2011 Jun;137(6):1037-51. doi: 10.1007/s00432-010-0969-6. Epub 2010 Dec 31.
A telomerase-specific oncolytic adenovirus, Telomelysin, can selectively kill cancer cells, and be attenuated in normal cells. We herein describe the oncolytic effect of Telomelysin on human osteosarcoma both in vitro and in vivo.
The anti-tumor effects of Telomelysin were evaluated on human osteosarcoma cell lines in vitro and in a mouse xenograft model of human osteosarcoma in vivo. The replication efficiencies of Telomelysin in human osteosarcoma cell lines and normal cell lines and in osteosarcoma xenografts were determined by the expression levels of E1 mRNA and E1A protein using real-time quantitative PCR, Western blot analysis and immunohistochemistry. The in vitro telomerase-specific replication and the viral infection rate were also confirmed by TelomeScan (Telomelysin-GFP), using fluorescent microscopy and flow cytometry, respectively. The cell viabilities were examined by XTT assay, and the tumor volumes were measured every 2 days. The induction of apoptosis was assessed by Western blot analysis, as well as by TUNEL assay.
TelomeScan and Telomelysin were efficiently replicated in human osteosarcoma cell lines and led to a dose- and time-dependent expression of GFP, E1 mRNA and E1A protein. Telomelysin infection induced marked cytolysis and apoptosis in osteosarcoma cell lines in vitro. Neither cytotoxicity nor apoptosis were induced in normal human cell lines. In the human osteosarcoma cell xenograft model, intratumoral injection of Telomelysin resulted in increased viral replication, significant tumor growth suppression and distinct apoptotic cell death.
This study indicated that virotherapy with Telomelysin may provide a promising strategy for the treatment of human osteosarcoma.
端粒酶特异性溶瘤腺病毒 Telomelysin 可以选择性地杀死癌细胞，并且在正常细胞中被减弱。本研究旨在描述 Telomelysin 对体外培养的人骨肉瘤细胞和体内人骨肉瘤异种移植模型的溶瘤作用。
在体外和体内人骨肉瘤异种移植模型中，评估 Telomelysin 对人骨肉瘤细胞系的抗肿瘤作用。通过实时定量 PCR、Western blot 分析和免疫组织化学检测 E1 mRNA 和 E1A 蛋白的表达水平，确定 Telomelysin 在人骨肉瘤细胞系和正常细胞系以及骨肉瘤异种移植中的复制效率。通过 TelomeScan（Telomelysin-GFP），分别使用荧光显微镜和流式细胞术，还证实了体外端粒酶特异性复制和病毒感染率。通过 XTT 测定法检测细胞活力，并每隔 2 天测量肿瘤体积。通过 Western blot 分析和 TUNEL 测定法评估细胞凋亡的诱导。
TelomeScan 和 Telomelysin 在人骨肉瘤细胞系中得到有效复制，并导致 GFP、E1 mRNA 和 E1A 蛋白的剂量和时间依赖性表达。Telomelysin 感染在体外诱导骨肉瘤细胞系明显的细胞溶解和凋亡。在正常的人细胞系中没有诱导出细胞毒性或细胞凋亡。在人骨肉瘤细胞异种移植模型中，瘤内注射 Telomelysin 导致病毒复制增加、肿瘤生长显著抑制和明显的凋亡细胞死亡。
这项研究表明，Telomelysin 的病毒治疗可能为治疗人骨肉瘤提供一种有前途的策略。
