CHEK2 mutations have previously been linked to chemotherapy resistance: Chrisanthar et al. [44] reported an association of CHEK2 mutations with resistance to anthracycline (doxorubicin and epirubicin) therapy in primary breast cancer and shown that decreased downstream p53 activation may contribute to anthracycline resistance in cancers with somatic deletion of wt CHEK2 allele (loss of heterozygosity; LOH). This evidence concerns the gene TP53 and breast cancer.