FOXP3 and neoplasm: Within the tumor microenvironment (TME), 4-OI reduced the frequencies of CD8+ and IFNγ+ CD8+ T cells (Figure S1K-L), but had no significant impact on CD4+, Foxp3+ CD4+ T cells, or myeloid-derived suppressor cells (MDSCs), including monocytic (M-MDSC) and granulocytic (M-MDSC) subsets (Figure S1M-P).