TP53 and breast cancer: Missense mutations in the TP53 gene often results in mutant p53 (mtp53) protein with gain-of-function (GOF) properties that are associated with multiple types of cancers, including lung and breast cancer.1 Mutations in p53 are found in 80% of triple negative breast cancers (TNBC).2–4 A number of studies have been carried out to elucidate the mtp53-associated breast cancer transcriptome but the mtp53-targeted proteome is less well studied.5–8 Mtp53 has not been found to interact with DNA site-specifically but has been found to interact with cancer cell DNA in association with other cofactors.