DKK1 and neoplasm: For instance, MSCs can produce and release Dickkopf-related protein 1 (Dkk-1) which in turn inhibit the expression of Wnt downstream targets and/or effectors such as BCL-2, cellular myelocytomatosis oncogene (c-Myc), β-catenin, BAX, and survivin in tumor cells (Table 2).177,215