CTLA4 and ovarian carcinoma: Cytotoxic T cell antigen-4 (CTLA-4) is another inhibitory checkpoint involved in T cell priming and activation [1], and translational studies in ovarian cancer have demonstrated that dual blockade of PD1/PDL1 and CTLA-4 increases tumor-infiltrating lymphocyte (TIL) activation and antigen-specific inflammatory cytokine production and decreases Tregs, potentially facilitating tumor rejection [10].