Dose dense chemotherapy, which is the term for Adriamycin and Cyclophosphamide (AC) followed by Taxol chemotherapy given every two weeks, is the standard chemotherapy for the treatment of ER+ or PR+ breast cancer. In this trial, the standard chemotherapy is being combined with bevacizumab. Bevacizumab is an antibody which works differently from the way other chemotherapy drugs work. Bevacizumab slows or stops cell growth in cancerous tumors by decreasing the blood supply to the tumors by binding to a substance found on cancer cells called VEGF (vascular endothelial growth factor). Bevacizumab is approved by the FDA for the treatment of colorectal cancer and lung cancer. However, it is not approved for the treatment of breast cancer. Another goal of this research is to determine whether we can develop a way to identify tumors that will respond well to this study treatment.