MDSCs can polarize macrophages toward the M2 phenotype, which promotes tumor progression, secrete IL-10 and TGF-β, induce the proliferation of Treg cells, and indirectly inhibit CD4+ Th1 and CD8+ T cell activity through the inhibition of DCs, exerting immunosuppressive functions (Yaseen et al., 2020). Here, TGFB1 is linked to neoplasm.