Abstract: The invention provides a wide range of methods and compositions for detecting and treating breast cancer in an individual. Specifically, the invention provides target breast cancer-associated proteins, which permit a rapid detection, preferably before metastases occur, of breast cancer. The target breast cancer-associated protein may be detected, for example, by reacting the sample with a labeled binding moiety, for example, a labeled antibody capable of binding specifically to the protein. The invention also provides kits useful in the detection of breast cancer in an individual. In addition, the invention provides methods utilizing the breast cancer-associated proteins either as targets for treating breast cancer or as indicators for monitoring the efficacy of such a treatment.