IL6 and breast cancer: Previous studies showed that brucine inhibited VEGF expression and decreased microvessel density in a nude mouse model of bone metastasis because of breast cancer [15], and brucine could inhibit cell proliferation, chemotactic motility and down-regulate levels of VEGF, NO, IL-6, IL-8, TNF-α and IFN-γ in HUVECs [14].