(86) found that a combination of dual checkpoint blockade therapy (anti-PD-L1 and anti-cytotoxic T-lymphocyte-associated protein-4) and X-ray irradiation could control primary osteosarcoma and diminish metastasis in vivo, which was associated with increased recruitment of CD8+ T cells and decreased infiltration of Tregs. This evidence concerns the gene CD8A and osteosarcoma.