CCN1 and neuroblastoma: Sclerostin is a protein member of DAN family that includes Wise, CCN [cysteine-rich 61 (Cyr61, CCN1), connective tissue growth factor (CTGF, CCN2) and nephroblastoma overexpressed (Nov, CCN3)], Dan (differential screening-selected gene aberrant in neuroblastoma), VWF (von Willebrand factor), Norrin, Mucin and Slits [1].