SHH and colorectal carcinoma: For example, in CD138+ myeloma stem cells, Shh signaling is activated by RARα2 [286] Referring to the contribution of Shh signaling to CSC-associated tumor metastasis, the study has shown that the degradation of Gli by RUNX3-mediated ubiquitination could reduce CSC-associated tumor metastasis in CRC [287].