TDE‐associated PD‐L1 and circulating IFNγ levels positively correlate in patients with metastatic melanoma, and IFNγ simulation increases PD‐L1 expression on these TDEs to suppress the function of CD8+ T‐cells and facilitate tumor growth (Figure 2).115 TDE PD‐L1 levels also vary during the course of anti‐PD‐1 therapy and the magnitude of the TDE PD‐L1 increase during early treatment, was found to stratify clinical responders from nonresponders.115, 124. This evidence concerns the gene CD8A and neoplasm.