CCBE1 and colorectal carcinoma: Since the mRNA level of CCBE1 is lower in HCT116 cells and higher in SW480 cells (Figure S1A), and SW480 is derived from a primary adenocarcinoma of the colon with lymph node metastasis 21.To clarify the biochemical function of CCBE1 secreted by CRC cells, we established HCT116 cells with stable CCBE1 overexpression and SW480 cells with stable CCBE1 knock down by two independent shRNAs (Figure S1B).