Second, as we have recently described a novel family of small-molecule compounds that affect the protein–protein interaction of transcription factors GATA4 and NKX2-5 and improve cardiac function in experimental models of myocardial infarction and hypertension (Ferreira et al. 2017; Kinnunen et al. 2018; Välimäki et al. 2017), we aimed to investigate if the lead compound 3i-1000 has cardioprotective potential against doxorubicin cardiotoxicity in vitro and in vivo. This evidence concerns the gene GATA4 and myocardial infarction.