CTLA4 and breast cancer: In the studies presented, expansion of CD8 T cells with cytolytic phenotype or function was observed with the combination of ixabepilone and anti-mCTLA-4 mAb in the EMT-6 mammary tumor model as well as with the pairing of etoposide and CTLA-4 blockade in the CT-26 colon carcinoma model.