IL1B and breast cancer: To investigate the role of IL-1 on breast cancer growth in bone we used two protocols outlined in Figure 1A: 1) A preventative protocol, in which 1mg/kg anakinra was injected every 24h for 31 days starting 3-days before injection of tumour cells to determine whether blocking IL-1R modified tumour cell homing and colonisation of bone; 2) a treatment protocol, in which 1mg/kg anakinra was injected every 24h for 21 days, starting 7 days after injection of tumour cells, to assess the effects on progression of established tumours.