Beijing International Science and Technology Cooperation Base of Antivirus Drug, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China.
Molecules. 2023 Jan 5;28(2):528. doi: 10.3390/molecules28020528.
As a tumor-targeting oncolytic adenovirus (Ad), conditionally replicating adenovirus (CRAd) can access the cell interior by binding to coxsackievirus-Ad receptors (CARs) and specifically replicate and destroy cancer cells without lethal effects on normal cells. The transduction efficiency of CRAd is highly dependent on the number of CARs on the cell membrane. However, not all tumor cells highly express CARs; therefore, improving the transduction efficiency of CRAd is beneficial for improving its antitumor effect. In this study, 6-cyclohexyl methyl-β-D-maltoside (6-β-D), as maltoside transfection agent, showed several advantages, including high transfection efficiency, low toxicity, and potential for intensive use and easy operation. With pretreatment of cancer cells with low concentration of 6-β-D (≤5 μg/mL), the transduction efficiency of "model" Ad (eGFP-Ad) was improved 18-fold compared to eGFP-Ad alone. 6-β-D improved the antitumor effect of CRAd while being safe for normal cells, in which treatment with 6-β-D helped the lethal effects of CRAd at a multiplicity-of-infection ratio of 10 (MOI 10) achieve the oncolytic outcomes of MOI 50. This means that if CRAd is combined with 6-β-D, the amount of CRAd used in clinical practice could be greatly reduced without diminishing its curative effect or exposing patients to the potential side effects of high-titer CRAd. Finally, the underlying mechanism of antitumor effect of CRAd + 6-β-D was primarily investigated, and we found that 6-β-D increased the virus's replication in cancer cells at the early stage of infection and activated the apoptosis signaling pathway at the late stage of the cell cycle. This research will provide an effective technical reference for further improving Ad-mediated cancer gene therapy in clinical practice.
作为一种肿瘤靶向溶瘤腺病毒（Ad），条件复制型腺病毒（CRAd）可以通过与柯萨奇病毒 - 腺病毒受体（CARs）结合进入细胞内部，并特异性复制和破坏癌细胞，而对正常细胞没有致命影响。CRAd 的转导效率高度依赖于细胞膜上 CARs 的数量。然而，并非所有肿瘤细胞都高度表达 CARs；因此，提高 CRAd 的转导效率有利于提高其抗肿瘤效果。在这项研究中，6-环己基甲基-β-D-麦芽糖苷（6-β-D）作为麦芽糖转染剂，具有高转导效率、低毒性、可密集使用、操作简便等优点。用低浓度的 6-β-D（≤5μg/mL）预处理癌细胞后，与单独使用 eGFP-Ad 相比，“模型”Ad（eGFP-Ad）的转导效率提高了 18 倍。6-β-D 提高了 CRAd 的抗肿瘤效果，同时对正常细胞安全，其中在感染复数（MOI）为 10 时，用 6-β-D 处理有助于 CRAd 的致死作用达到 MOI 50 的溶瘤效果。这意味着如果将 CRAd 与 6-β-D 联合使用，在不降低疗效或使患者暴露于高滴度 CRAd 的潜在副作用的情况下，可以大大减少临床实践中 CRAd 的用量。最后，主要研究了 CRAd+6-β-D 的抗肿瘤作用机制，我们发现 6-β-D 在感染的早期阶段增加了病毒在癌细胞中的复制，并在细胞周期的晚期激活了细胞凋亡信号通路。这项研究将为进一步提高临床实践中 Ad 介导的癌症基因治疗提供有效的技术参考。
