Cancer-derived factors induce fibroblast clustering and production of HGF/scatter factor, which, in turn, enhances the invasiveness of c-Met-expressing carcinoma and leukemia cells through IL1, -6, -8, and 11, leukemia inhibitor factor, and granulocyte-macrophage colony-stimulating factor in a process termed nemosis [216,217]. The gene discussed is IL1A; the disease is cancer.