TNF and neoplasm: Paracrine stimulation by pro-inflammatory moleculessuch as TNF-α, IL-1β, and MIP-2, leads to increased synthesis of chemokines andexpression of cell adhesion molecules such as ICAM-1, E-selectin, and vascularcell adhesion molecule-1 (VCAM-1) by cerebrovascular endothelial cells[52], which may increase anchorageof tumor cells and eventually lead to facilitated cellular invasion from thecirculation into the brain [53].These same changes may directly or indirectly lead to increased ability of MDSCs,TAMs, and TANs to enter the brain and further influence tumor cell entry acrossthe BBB.