The role of YB-1 in DNA damage repair was further validated as we found that YB-1 knockdown induces the increase of ATR phosphorylation (Ser428), PAR, and γH2AX in CML cells (Fig. 6h and Supplementary Fig. 6c). This evidence concerns the gene YBX1 and chronic myelogenous leukemia, BCR-ABL1 positive.