DKK1 and cancer: Discrepancies and conflicting data present in the literature may depend not only on the type of cancer but, at least in colorectal neoplasias, also on the location of DKK-1 protein and the stage of tumor progression: the presence of DKK-1 within the cell nucleus seems to be specifically responsible for drug resistance and so, the analysis of the subcellular distribution of DKK-1 is warranted.