POU5F1 and myocardial infarction: Importantly, we showed that Oct4 knockdown by transfection of an Oct4 shRNA completely eliminated the cardiac effects of both β-catenin overexpression and PBMSC therapy (oeβ-catenin+shOct4), as shown by worsening cardiac function, augmented fibrosis, myocardial infarct size and loss, and decreased myocardial engraftment of PBMSCs.