CCN1 and Wilms tumor: The CCN family is a group of secreted proteins that specifically associate with other extracellular matrix proteins and consists of 6 members: CCN1 (cysteine-rich 61, CYR61), CCN2 (connective tissue growth factor, CTGF), CCN3 (overexpressed in nephroblastoma, NOV), CCN4 (Wnt-1 induced secreted protein-1, WISP1), CCN5 (Wnt-1 induced secreted protein-2, WISP2) and CCN6 (Wnt-1 induced secreted protein-3, WISP3) (Brigstock, 2003).