C2 and hepatocellular carcinoma: Morris et al.41examined the complement biosynthesis function of a well‐differentiated HCC cell line—HepG2 and found that HepG2 synthesized and secreted functional complement proteins C1r, C1s, C2, C3, C4, C5, factor B, C1 inhibitor, C3b inactivator, a small amount of C6, and trace amounts of C8; but failed to produce detectable C1q, C7, or C9,42 which supported our hypothesis.