DKK1 and renal carcinoma: The Dickkopf class of Wnt antagonists including DKK1, DKK2 and DKK3 are also epigenetically silenced in renal cancer and their over-expression induced apoptosis and inhibited renal cell growth in-vitro and in-vivo [22,23,109], whereas DKK4 was found higher in renal cancer compared to normal tissue samples and it activated the non-canonical Wnt pathway in renal cancer thereby promoting the invasive and migratory capability of renal cancer cells [24].