Patients are then treated with a very high dose of another anti-breast cancer drug, one that is very toxic to bone marrow cells, and patients will then receive the frozen PBPCs, which contain the new genes, to help them recover from the chemotherapy. After recovery, patients will then be treated with high doses of paclitaxel (Taxol) and doxorubicin (Adriamycin) chemotherapy. Both of these drugs are very active against breast cancer, and the MDR1 gene may potentially protect bone marrow cells against these drugs. Samples of peripheral blood cells will be obtained before each of these doses of chemotherapy to determine whether the number of blood cells that contain the MDR1 gene in comparison to the number that contain the NeoR gene has increased in response to the chemotherapy.