GREM1 and colorectal carcinoma: Collectively, we identified four proteins (GREM1, CLSTN3, CSF2RA, CD86) with the most convincing evidence (tier 1), five proteins with convincing evidence (tier 2), and four proteins with middle convincing evidence (tier 3), among which six (CLSTN3, POLR2F, ADPGK, CSAG1, STXBP6, FUT3) were novel plasma protein makers associated with CRC.