In melanoma-bearing mice receiving IL-2- and TNF-α-coding adenovirus in combination with adoptive T-cell therapy, PD-L1 was upregulated in intratumoral MDSCs, and the frequency of PD-1+ CD8+ T cells correlated with the PD-L1 expression level on MDSCs in tumor site (70). The gene discussed is PDCD1; the disease is neoplasm.