PDCD1 and osteosarcoma: Antagonistic anti-CTLA-4 antibodies have been verified to improve the HLA binding ability of TILs in melanoma as well as facilitate CD8+ TIL proliferation in Lewis lung carcinoma.256 A recent study also revealed that TIL-based strategies in combination with anti-PD1 antibody therapy showed excellent therapeutic efficacy in patients with pulmonary metastasis of osteosarcoma.367