CTLA4 and cancer: Other IFNγ-regulated gene is RBCK1, which showed markedly differential expression levels in cancer, and significantly correlated with tumor-infiltrating immune cells, tumor purity, and immune checkpoint molecules, such as PD-L1, CTLA-4, Lag-3, and T-cell immunoglobulin and ITIM domain (TIGIT) in pan-cancer samples [181].