Molecular basis of ndt‐mediated activation of nucleoside‐ based prodrugs and application in suicide gene therapy

Abstract

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‐fluor-ouridine (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.