CTLA4 and breast carcinoma: They injected histone deacetylase inhibitor trichostatin A (TSA) mouse breast carcinoma cells into mice and were randomly assigned to eight groups receiving no RT or three distinct regimens of RT (20 Gy × 1, 8 Gy × 3, or 6 Gy × 5 fractions in consecutive days) with or without specific monoclonal antibody (9H10), against cytotoxic T-lymphocyte associated protein-4 (CTLA-4).