DKK1 and cancer: Elevated serum DKK1 has been found to be associated with worse survival in cancers from multiple organs including the pancreas [32], stomach [33, 34], liver [35, 36], ovary [37], bile duct [38], bladder [39, 40], prostate [41, 42], breast [43, 44], cervix [45, 46] and esophagus [47, 48].