Gene therapy for breast cancer. — review of clinical gene therapy trials for breast cancer and mdr1 gene therapy trial in cancer institute hospital

Gene therapy for advanced breast cancer is anticipated to be a useful therapeutic approach. Strategies in ongoing clinical protocols can be divided into four groups: (1) suppression of oncogenes or transfer of tumor-suppressor genes; (2) enhancement of immunological response; (3) transfer of suicide genes; (4) protection of bone marrow using drug resistance genes. We have started a clinical study of multidrug resistance (MDRl) gene therapy. Advanced breast cancer patients received high dose chemotherapy and autologous peripheral blood stem cell transplantation (PBSCT) withMDRl-transduced hematopoietic cells, and then were treated with docetaxel. Two patients have been treated so far, andin vivo enrichment ofMDRl-transduced cells with docetaxel treatment has been seen. Both patients are in complete remission and had no apparent adverse effects from theMDRl gene transfer.