Like circRNA Slc8a1, circRNA HIPK3 has been shown to sponge miR-133a in a model of MI, enhancing Notch1 and connective tissue growth factor (CTGF) expression thereby driving proliferation, migration, and fibrosis in a manner protective against heart failure [120, 121]. The gene discussed is HIPK3; the disease is myocardial infarction.