Background: Anthracyclines are a class of highly effective chemotherapeutics, yet their use is regularly complicated by anthracycline-induced cardiotoxicity (AIC). The advent of induced pluripotent stem cell-derived cardiac myocytes (iPSC-CMs) offers the potential for disease modeling and prediction of genetic cardiomyopathies. Purpose: We aim to use iPSC-CMs to assess susceptibility to AIC. Methods: Five AIC heart transplant patients and five anthracycline treated patients without AIC were included in our study. We reprogrammed lymphocytes from both groups toward iPSCs using Sendai Virus, followed by differentiation into CM-like cells. Cytotoxicity following chemotherapy exposure was assessed using flow cytometry (FC), electron microscopy (EM) and reactive oxygen species generation (ROS). Furthermore, whole genome sequencing (WGS) was performed and variants were filtered based on allele frequency, pathogenicity using HumVar trained variant effect predictors and presence in patients versus controls. Results: The cytotoxic effect of increasing concentrations of doxorubicin was quantifiable using FC on SIRPA positive iPSC-CMs ( A ). There was a higher rate of cell death at any concentration of doxorubicin in patients with AIC as opposed to controls ( B ). On the ultrastructural level, doxorubicin treated iPSC-CMs manifested darker and more condensed mitochondria as seen with EM ( C ). Increased ROS production was observed following doxorubicin exposure ( D ). WGS analysis showed 2 pathogenic variants in the PRAMEF6 gene present in cases and not in controls ( E ). Conclusion: iPSC-CMs represent a robust disease model to study mechanisms of and susceptibility to AIC.
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