Herein we report the first proof for the application of type II 2′-deoxyribosyltransferase from Lactobacillus delbrueckii (LdNDT) in suicide gene therapy for cancer treatment. To this end, we first confirm the hydrolytic ability of LdNDT over the nucleoside-based prodrugs 2′-deoxy-5-fluorouridine (dFUrd), 2′-deoxy-2-fluoroadenosine (dFAdo), and 2′-deoxy-6-methylpurine riboside (d6MetPRib). Such activity was significantly increased (up to 30-fold) in the presence of an acceptor nucleobase. To shed light on the strong nucleobase dependence for enzymatic activity, different molecular dynamics simulations were carried out. Finally, as a proof of concept, we tested the LdNDT/dFAdo system in human cervical cancer (HeLa) cells. Interestingly, LdNDT/dFAdo showed a pronounced reduction in cellular viability with inhibitory concentrations in the low micromolar range. These results open up future opportunities for the clinical implementation of nucleoside 2′-deoxyribosyltransferases (NDTs) in cancer treatment.

中文翻译：

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NDT介导核苷基前药激活的分子基础及其在自杀基因治疗中的应用

本文中，我们报道了来自德氏乳杆菌（Ld NDT）的II型2'-脱氧核糖基转移酶在自杀基因治疗癌症中的应用的第一个证据。为此，我们首先确认Ld NDT对基于核苷的前药2'-脱氧-5-氟尿苷（dFUrd），2'-脱氧-2-氟腺苷（dFAdo）和2'-脱氧-6的水解能力。-甲基嘌呤核糖苷（d6MetPRib）。在受体核碱基的存在下，这种活性显着增加（高达30倍）。为了阐明酶活性对核碱基的强依赖性，进行了不同的分子动力学模拟。最后，作为概念证明，我们测试了Ld人类宫颈癌（HeLa）细胞中的NDT / dFAdo系统。有趣的是，Ld NDT / dFAdo在低微摩尔范围内抑制浓度下，细胞活力显着降低。这些结果为在癌症治疗中临床应用核苷2'-脱氧核糖基转移酶（NDT）开辟了未来的机会。