Hingorani et al. studied the immune population present in the bloodstream of pediatric osteosarcoma and Ewing sarcoma patients and found an increased expression of CTLA-4 in both CD4+ and CD8+ T cells, together with a population of CD14(+) HLA-DR(lo/neg) immunosuppressive monocytes, which were correlated with advanced disease [92]. This evidence concerns the gene CTLA4 and osteosarcoma.