TGFB1 and cancer: Once they become residents in the TIME, M2 cells start to produce VEGF, which enhances the “feed-forward” loop, attracting new macrophages to the TIME, and TGF-β, one of the most potent immunosuppressive cytokines, which transforms normal fibroblasts and probably other stromal cells into cancer-associated fibroblasts (CAFs) [45].