C4BPA and hepatocellular carcinoma: In another proteomic quantitative analysis study involving 21 HCC patients and 15 healthy controls, a series of complement-related proteins were identified and validated to be upregulated in HCC patients, including complement C1Q subcomponent subunit B (C1QB), complement C1Q subcomponent subunit C (C1QC), C4B-binding protein alpha chain (C4BPA), and C4B-binding protein beta chain (C4BPB), further elucidating the role of the complement activation pathway in the tumorigenesis of HCC [98].