CTLA4 and cancer: Furthermore, additional immune-suppressive receptors are upregulated in the cancer inflammatory microenvironment, i.e., T cell immunoglobulin mucin 3 (TIM-3), cytotoxic T lymphocytes antigen 4 (CTLA-4), glucocorticoid-induced TNFR (tumor necrosis factor receptor)-related protein (GITR), and lymphocyte-activation gene 3 (LAG-3) (8).