These signaling pathways such as Role of BRCA1 in DNA Damage Response, Hereditary Breast Cancer, ATM, Molecular Mechanisms of Cancer, Estrogen-Dependent Breast Cancer, Cell Cycle Regulation, p53 Signaling, FGF Signaling, Role of CHK Proteins in Cell Cycle Checkpoint Control, MYC Mediated Apoptosis, NF-kB, and PTEN Signaling pathways could serve as targets for the development of novel therapeutics. This evidence concerns the gene ATM and breast cancer.