For example, the HR protein BRCA1 (Breast cancer 1, early onset) has been shown to direct the transcriptional program of the tumor suppressor p53 towards treatment survival, as described in more detail below [78] (Section 3.3) The canonical function of BRCA1 in DNA repair involves different steps of the HR pathway, e.g., RAD51-dependent strand invasion and D-loop formation, as reviewed in detail elsewhere [23]. This evidence concerns the gene TP53 and breast cancer.