APLP2 and colorectal carcinoma: The five proteins that were most significantly upregulated in the secretome samples of CRC cell lines (Caco-2, HT29, and HCT116) were DDR1 (FC = 7.4), APLP2 (FC = 5.7), SERPINA1 (FC = 37.4), SPINT1 (FC = 21.6), and FAM3C (FC = 7.8) (listed in order of decreasing significance).