Division of Pathology and Cell Therapy, Chiba Cancer Center Research Institute, Chiba, Japan.
Department of Molecular Biology and Oncology, Graduate School of Medicine, Chiba University, Chiba, Japan.
BMC Cancer. 2017 Sep 5;17(1):622. doi: 10.1186/s12885-017-3621-x.
Replication-competent adenoviruses (Ad) produced cytotoxic effects on infected tumors and have been examined for the clinical applicability. A biomarkers to predict the cytotoxicity is valuable in a clinical setting.
We constructed type 5 Ad (Ad5) of which the expression of E1A gene was activated by a 5' regulatory sequences of survivin, midkine or cyclooxygenase-2, which were highly expressed in human tumors. We also produced the same replication-competent Ad of which the fiber-knob region was replaced by that of Ad35 (AdF35). The cytotoxicity was examined by a colorimetric assay with human tumor cell lines, 4 kinds of pancreatic, 9 esophageal carcinoma and 5 mesothelioma. Ad infectivity and Ad-mediated gene expression were examined with replication-incompetent Ad5 and AdF35 which expressed the green fluorescence protein gene. Expression of cellular receptors for Ad5 and AdF35 was also examined with flow cytometry. A transcriptional activity of the regulatory sequences was investigated with a luciferase assay in the tumor cells. We then investigated a possible correlation between Ad-mediated cytotoxicity and the infectivity/gene expression, the transcriptional activity or the p53 genotype.
We found that the cytotoxicity was greater with AdF35 than with Ad5 vectors, but was not correlated with the Ad infectivity/gene expression irrespective of the fiber-knob region or the E1A-activating transcriptional activity. In contrast, replication-competent Ad produced greater cytotoxicity in p53 mutated than in wild-type esophageal carcinoma cells, suggesting a possible association between the cytotoxicity and the p53 genotype.
Sensitivity to Ad-mediated cytotoxic activity was linked with the p53 genotype but was not lineally correlated with the infectivity/gene expression or the E1A expression.
复制型腺病毒（Ad）在感染的肿瘤上产生细胞毒性作用，并已在临床应用中进行了研究。在临床环境中，预测细胞毒性的生物标志物是有价值的。
我们构建了 5 型腺病毒（Ad5），其 E1A 基因的表达由生存素、中期因子或环氧化酶-2 的 5'调控序列激活，这些基因在人类肿瘤中高度表达。我们还生产了相同的复制型腺病毒，其纤维小珠区域被 Ad35（AdF35）的纤维小珠区域取代。通过用 4 种胰腺癌、9 种食管癌和 5 种间皮瘤的人肿瘤细胞系进行比色测定来检测细胞毒性。用表达绿色荧光蛋白基因的无复制能力的 Ad5 和 AdF35 检测 Ad 感染性和 Ad 介导的基因表达。用流式细胞术检测细胞对 Ad5 和 AdF35 的受体表达。用荧光素酶测定法在肿瘤细胞中研究调控序列的转录活性。然后，我们研究了 Ad 介导的细胞毒性与感染性/基因表达、转录活性或 p53 基因型之间的可能相关性。
我们发现，与 Ad5 载体相比，AdF35 的细胞毒性更大，但与纤维小珠区域或 E1A 激活转录活性无关，与 Ad 感染性/基因表达无关。相反，在 p53 突变的食管癌细胞中，复制型腺病毒产生了更大的细胞毒性，这表明细胞毒性与 p53 基因型之间存在可能的关联。
对 Ad 介导的细胞毒性活性的敏感性与 p53 基因型有关，但与感染性/基因表达或 E1A 表达没有线性关系。
