TP53 and breast carcinoma: TP53 mutations affecting or disrupting the zinc atom chelating, L2/L3 DNA binding domains of the p53 protein are linked to primary resistance to doxorubicin therapy in breast cancer. Furthermore polymorphism in codon 72 (Arg/Pro) of p53 affects cellular sensitivity to anticancer drugs such as doxorubicin through inhibition of p73, a protein related to p53.