In contrast to HIF-1α-deficient tumor-infiltrating CD8+ T cells, however, PD-1 expression in VEGF-deficient tumor-infiltrating lymphocytes (TILs) is unaffected (Figure 6D) and there are no changes in FOXP3 expression levels in infiltrating CD4+ T cells (Figure 6E). The gene discussed is CD4; the disease is neoplasm.