WISP-1 belongs to the CCN (CTGF/CYR61/NOV) family of secreted proteins that share a common multimodular organization. Each family member has an IGFBP domain, a von Willebrand type C domain, a thrombospondin 1 domain and a C-terminal cysteine knot domain. Depending on cell context, WISP-1 can either promote or inhibit tumorigenesis.