CD274 and osteosarcoma: Strategies that suppress this interaction have shown significant therapeutic effects in cancer patients, including osteosarcoma patients.312,313 The expression levels of PD-L1 vary widely among osteosarcoma cell lines but are higher than those in parental cell lines.314 Moreover, the expression of PD-L1 shows a positive association with chemotherapy resistance and the quantity of TILs as well as with osteosarcoma cell proliferation.315,316 Consequently, high expression levels of PD-L1 are associated with worse survival time than low PD-L1 expression in osteosarcoma patients.