Figure 4.

Disease status does not significantly influence the expression of immune checkpoint genes. Comparative analysis of (A, E) PD-L1, (B, F) PD-L2, (C, G) B7-H3, and (D, H) IDO1 gene expression in diagnostic versus metastatic osteosarcoma samples using RNA-sequencing data from the (A-D) St. Jude osteosarcoma (n = 23) and the (E-H) NCI TARGET osteosarcoma (n = 81) datasets. Statistical significance (p ≤ 0.05) determined using unpaired two-tailed t-tests with Welch’s correction. FPKM, fragments per kilobase of transcript mapped; TPM, transcripts per million.