Herpes simplex virus-1 (HSV-1) oncolytic therapy and gene therapy are promising treatment modalities against cancer. NV1066, one such HSV-1 virus, carries a marker gene for enhanced green fluorescent protein (EGFP). The purpose of this study was to determine whether NV1066 is cytotoxic to lung cancer and whether EGFP is a detectable marker of viral infection in vitro and in vivo. We further investigated whether EGFP expression in infected cells can be used to localize the virus and to identify small metastatic tumor foci (<1 mm) in vivo by means of minimally invasive endoscopic systems equipped with fluorescent filters. In A549 human lung cancer cells, in vitro viral replication was determined by plaque assay, cell kill by LDH release assay, and EGFP expression by flow cytometry. In vivo, A549 cells were injected into the pleural cavity of athymic mice. Mice were treated with intrapleural injection of NV1066 or saline and examined for EGFP expression in tumor deposits using a stereomicroscope or a fluorescent thoracoscopic system. NV1066 replicated in, expressed EGFP in infected cells and killed tumor cells in vitro. In vivo, treatment with intrapleural NV1066 decreased pleural disease burden, as measured by chest wall nodule counts and organ weights. EGFP was easily visualized in tumor deposits, including microscopic foci, by fluorescent thoracoscopy. NV1066 has significant oncolytic activity against a human NSCLC cell line and is effective in limiting the progression of metastatic disease in an in vivo orthotopic model. By incorporating fluorescent filters into endoscopic systems, a minimally invasive means for diagnosing small metastatic pleural deposits and localization of viral therapy for thoracic malignancies may be developed using the EGFP marker gene inserted in oncolytic herpes simplex viruses.

中文翻译：

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溶酶性单纯疱疹病毒治疗转移性胸膜癌的微创定位。

单纯疱疹病毒1（HSV-1）溶瘤疗法和基因疗法是抗癌的有前途的治疗方法。NV1066是一种此类HSV-1病毒，带有增强型绿色荧光蛋白（EGFP）的标记基因。这项研究的目的是确定NV1066是否对肺癌具有细胞毒性，以及EGFP是否在体内外均可检测到病毒感染。我们进一步调查了是否可以通过配备荧光滤光片的微创内窥镜系统在体内感染的细胞中的EGFP表达是否可用于定位病毒并在体内鉴定小的转移性肿瘤灶（<1 mm）。在A549人肺癌细胞中，通过噬菌斑测定，通过LDH释放测定杀死细胞，通过流式细胞术确定EGFP的表达来确定体外病毒复制。体内，将A549细胞注射到无胸腺小鼠的胸膜腔中。胸膜内注射NV1066或生理盐水治疗小鼠，并使用体视显微镜或荧光胸腔镜系统检查肿瘤沉积物中EGFP的表达。NV1066在感染的细胞中复制并表达EGFP，并在体外杀死肿瘤细胞。在体内，采用胸膜内结节计数和器官重量来衡量，采用胸膜内NV1066治疗可降低胸膜疾病负担。通过荧光胸腔镜检查，很容易在包括显微灶在内的肿瘤沉积物中观察到EGFP。NV1066对人NSCLC细胞系具有显着的溶瘤活性，可有效限制体内原位模型中转移性疾病的进展。通过将荧光滤光片纳入内窥镜系统，