PARP1 and breast cancer: Poly(ADP‐ribose) polymerase activation has been shown to prevent mitophagy in xeroderma pigmentosum group A‐deficient cells, and PARP inhibition by the inhibitor olaparib induces mitophagy in BRCA1 and BRCA2 mutant breast cancer cells.10, 11 However, whether PARP activation regulates mitophagy in I/R‐injured cardiomyocytes remains unclear.