IL6 and neoplasm: Interleukin-6 (IL-6) is a cytokine with pleiotropic activities, being produced by many different cell types including monocytes/macrophages, fibroblasts, keratinocytes, endothelial cells, mesangial cells, glial cells, chondrocytes, osteoblasts, smooth muscle cells, T cells, B cells, granulocytes, mast cells, and certain tumor cells [69].