IL-6 antibody treatment inhibits in vitro cell proliferation and in vivo tumor growth in both ER+ MCF7 cells and TNBC, MDA-MB-231 cells through a blockade of STAT3 activation and associated downregulation of STAT3 target genes including SOCS3, IL6ST and genes involved in angiogenesis [129,130]. The gene discussed is STAT3; the disease is neoplasm.