Assessment of early DNA damage induced in human fibroblasts by four therapeutic radionuclides using Geant4-DNA

Abstract

PurposeQuantifying the initial damage induction is necessary to understand the dependence of the late effects on radiation quality. This study was conducted to better understand the effects of therapeutic radionuclides on human cells and to improve the therapeutic efficacy of TRT. MethodsIn this study, early direct and indirect DNA damage induced by four widely used therapeutic radionuclides (Y-90, I-131, Lu-177, and I-125) in human fibroblasts was investigated using Geant4 DNA. The relative effects of direct and indirect damage induction on DNA and human cells were evaluated using complexity and source classification. In addition, we performed an analysis of the histogram of fragment length distribution for therapeutic radionuclides. ResultsThe results of this study showed that the highest single-strand break (SSB) and double-strand break (DSB) yields based on source classification are due to the relative effects of indirect damage induction on DNA and human cells. Radionuclide I-131 has the highest yield of SSB, while I-125 has the highest yield of DSB. On the other hand, Y-90 has the lowest SSB and DSB yield values. The study also revealed that I-125 has the highest fragment length distribution, while Y-90 has the lowest. ConclusionAmong the therapeutic radionuclides, I-131 and I-125 had the greatest effect on SSB and DSB yield values, respectively, while Y-90 had little effect.