To investigate whether the addition of CTLA-4 blockade to ixabepilone modulated the immune response to tumors, mice which were previously treated with ixabepilone or ixabepilone plus anti-mCTLA-4 mAb that were tumor-free were rechallenged on Day 95 with M109 tumor cells subcutaneously. The gene discussed is CTLA4; the disease is neoplasm.