IL1B and neoplasm: In contrast to previous studies showing increased VEGF expression in endothelial cells treated with IL-1B [34] and reduced IL-1B and TNF alpha activity in bone marrow mononuclear cells stimulated with VEGF [35], we did not see a significant decrease in VEGF gene expression in either mouse bone or MDA-MB-231-IV tumours growing in bone following administration of anakinra, compared with placebo.