Xinyuan Institute of Medicine and Biotechnology, College of Biological Sciences, Zhejiang Sci-Tech University, Hangzhou 310018, China.
Acta Pharmacol Sin. 2013 Apr;34(4):531-40. doi: 10.1038/aps.2012.196. Epub 2013 Mar 18.
The tumor suppressor in lung cancer-1 (TSLC1) is a candidate tumor suppressor of lung cancer, and frequently inactivated in primary non-small cell lung cancer (NSCLC). In this study, we investigated the effects of TSLC1 mediated by a dual-regulated oncolytic adenovirus on lung cancer, and the mechanisms underlying the antitumor actions.
The recombinant virus Ad·sp-E1A(Δ24)-TSLC1 was constructed by inserting the TSLC1 gene into the dual-regulated Ad·sp-E1A(Δ24) vector, which contained the survivin promoter and a 24 bp deletion within E1A. The antitumor effects of Ad·sp-E1A(Δ24)-TSLC1 were evaluated in NCI-H460, A549, and H1299 lung cancer cell lines and the normal fibroblast cell line MRC-5, as well as in A549 xenograft model in nude mice. Cell viability was assessed using MTT assay. The expression of TSLC1 and activation of the caspase signaling pathway were detected by Western blot analyses. The tumor tissues from the xenograft models were examined using H&E staining, IHC, TUNEL, and TEM analyses.
Infection of A549 lung cancer cells with Ad·sp-E1A(Δ24)-TSLC1 induced high level expression of TSLC1. Furthermore, the Ad·sp-E1A(Δ24)-TSLC1 virus dose-dependently suppressed the viability of NCI-H460, A549, and H1299 lung cancer cells, and did not affect MRC-5 normal fibroblast cells. Infection of NCI-H460, A549, and H1299 lung cancer cells with Ad·sp-E1A(Δ24)-TSLC1 induced apoptosis, and increased activation of caspase-8, caspase-3 and PARP. In A549 xenograft model in nude mice, intratumoral injection of Ad·sp-E1A(Δ24)-TSLC1 significantly suppressed the tumor volume, and increased the survival rate (from less than 15% to 87.5% at d 60). Histological studies showed that injection of Ad·sp-E1A(Δ24)-TSLC1 caused tumor cell apoptosis and virus particle propagation in tumor tissues.
The oncolytic adenovirus Ad·sp-E1A(Δ24)-TSLC1 exhibits specific antitumor effects, and is a promising agent for the treatment of lung cancer.
肺癌肿瘤抑制因子 1（TSLC1）是一种候选的肺癌肿瘤抑制因子，在原发性非小细胞肺癌（NSCLC）中经常失活。本研究旨在探讨双调控溶瘤腺病毒介导的 TSLC1 对肺癌的影响及其抗肿瘤作用的机制。
构建了含有生存素启动子和 E1A 内 24 个碱基缺失的双调控腺病毒 Ad·sp-E1A(Δ24)载体，将 TSLC1 基因插入该载体中，构建重组病毒 Ad·sp-E1A(Δ24)-TSLC1。采用 MTT 法评估 Ad·sp-E1A(Δ24)-TSLC1 对 NCI-H460、A549 和 H1299 肺癌细胞系及正常成纤维细胞系 MRC-5 的抗肿瘤作用，并用裸鼠 A549 移植瘤模型进行检测。Western blot 检测 TSLC1 的表达和半胱天冬酶信号通路的激活。采用 H&E 染色、免疫组化（IHC）、TUNEL 和 TEM 分析检测移植瘤组织。
Ad·sp-E1A(Δ24)-TSLC1 感染 A549 肺癌细胞可诱导 TSLC1 的高表达。此外，Ad·sp-E1A(Δ24)-TSLC1 病毒呈剂量依赖性抑制 NCI-H460、A549 和 H1299 肺癌细胞的活力，但对 MRC-5 正常成纤维细胞无影响。Ad·sp-E1A(Δ24)-TSLC1 感染 NCI-H460、A549 和 H1299 肺癌细胞可诱导细胞凋亡，并增加半胱天冬酶-8、半胱天冬酶-3 和 PARP 的激活。在裸鼠 A549 移植瘤模型中，瘤内注射 Ad·sp-E1A(Δ24)-TSLC1 可显著抑制肿瘤体积，并提高生存率（第 60 天从<15%提高到 87.5%）。组织学研究表明，Ad·sp-E1A(Δ24)-TSLC1 注射可引起肿瘤细胞凋亡和病毒颗粒在肿瘤组织中的传播。
溶瘤腺病毒 Ad·sp-E1A(Δ24)-TSLC1 具有特异性抗肿瘤作用，是治疗肺癌的一种有前途的药物。
