CASP3 and Myocardial fibrosis: Additionally, PAP-3.2KD reversed histopathological changes (such as disordered muscle bundles, myocardial fibrosis and diffuse myocardial cellular edema) and scores of the heart tissue, ameliorated the myocardial fibrosis and collagen volume fraction through pathological examination, significantly increased the protein level of Bcl-2, and decreased the expression levels of Bax and caspase-3 in myocardial tissue by ELISA, compared to those in ADR-induced group.