TGFB1 and neoplasm: GBM also alters the TME composition through immunoevasive strategies, including the secretion of immunosuppressive cytokines like transforming growth factor-beta (TGF-β) and interleukin-10 (IL-10) [54], upregulation of programmed death-ligand 1 (PD-L1) on tumor cells to inhibit T cell function [55], and recruitment of regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) to suppress anti-tumor immunity [56].