IL6 and neoplasm: Monocytes release monocyte chemoattractant protein- (MCP-) 1 to stimulate and mediate tumor-associated monocyte infiltration in solid tumors and then produce various chemokines, such as TGF-α, tumor necrosis factor- (TNF-) α, interleukin- (IL-) 1, and IL-6 which promote tumorigenesis, angiogenesis, and distant metastasis of malignant tumors [20].