LIF and neoplasm: These factors (1) induce cell proliferation, such as epidermal growth factor (EGF) family members and interleukin (IL)-6, (2) trigger angiogenesis, e.g. vascular EGF (VEGF), basic FGF, and IL-8, (3) attract immune cells to the tumor, in particular chemokines of the CCL and CXCL families [17], and (4) polarize these to pro-tumorigenic and immune suppressive cells, for example VEGF, IL-6, IL-10, and LIF [18].