IL1B and cancer: Although the in vivo relevance of these data has not yet been experimentally addressed, a second level of SNS action on the bone microenvironment in the context of skeletal metastasis could thus be a stimulatory effect on osteoblast-derived IL1β, leading to enhanced adhesive properties of the bone vascular network for metastatic cancer cells and promotion of the arrest of these cells into the skeleton, in a E/P-selectin-dependent manner.