APOB and cholangiocarcinoma: The study clarified several proteins that were significantly elevated in CCA patients compared to PSC and benign cases such as α-s-macroglobulin, apolipoprotein B-100 (Apo-B), ceruloplasmin, complement C3, kininogen-1 (KNG1) isoform 2, myeloperoxidase (MPO), and inter-α-trypsin inhibitor heavy chain H4 (ITIH4) [83].