Importantly, γH2AX foci form in response to DSBs [57], and the presence of foci can be utilized as a biomarker to measure DNA damage induced by PARP inhibition [59]. BRCA1-mutated acute myeloid leukemia cells that were exposed to Olaparib subsequently formed γH2AX foci, suggesting that γH2AX foci formation may be a useful biomarker for successful PARP inhibition [59]. Here, PARP1 is linked to acute myeloid leukemia.