Figure 2.

Regulation of tumor angiogenesis by different immune cells. mDCs and M1-type TAMs release IFN-α, IL-12, and other cytokines, alongside chemokines like CXCL9 and CXCL10, to inhibit angiogenesis. CD8⁺T cells and TH1 cells additionally secrete IFN-γ, which suppresses angiogenesis and promotes vascular normalization. Conversely, iDCs, MDSCs, M2-type TAMs, and TEM cells promote angiogenesis through factors like VEGF and IL-10, while Tregs, TH2, and TH17 cells contribute by releasing VEGF and IL-4. Immune cells further regulate angiogenesis through interactions. For instance, mDCs and TH1 cells can polarize macrophages toward the M1 type, whereas MDSCs and Tregs reprogram TAMs toward the M2 type. Some MDSCs can even differentiate into endothelial-like cells and incorporate into the tumor vasculature.