DKK1 and plasma cell myeloma: The elevated levels of Dkk-1 were correlated with a poor prognosis in patients suffering from multiple myeloma, prostate cancer, hepatocellular carcinoma and non-small cell lung cancer (NSCLC) (Politou et al., 2006; Yang et al., 2013; Dong et al., 2014; Rachner et al., 2014).