TNF and neoplasm: Additionally, as a response to signals from tumor cells in TME, TAMs upregulate the lipid biosynthesis to generate more ROS and produce higher levels of extracellular cytokines like interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and so on, which ultimately promotes cancer cell survival, metastasis, angiogenesis and immune suppression 52.