Sugar chain alterations of α-fetoptotein (AFP),α1-Antitrypsin (AAT) and transferrin (Tf) in spent culture media of human hepatoma cell lines, HuH-7, huH-1, Hep-G2 and KIM-1, were analyzed by lectin-affinity electrophoresis with Concanavalin A (Con A), Lens culinaris agglutinin (LCA) and Phaseolus vulgaris lectin (E4-PHA) and antibody-affinty blotting. Their glycoforms demonstrated lectin-dependent characteristic patterns similar to the glycoforms of AFP in hepatocellular carcinomas, although their separation became less chear as the number of sugar chains per molecule increased. The proportions of band intensities of the glycoform of AAT and Tf corresponding to AFP-C1, AFP-L3 and AFP-P4 increased consistently in all cell lines. However, the extent of the increases in the glycoforms differed from one cell line to another, reflecting tumor heterogenity. On the other hand, the sugar chain alterations of glycoproteins were similar in each cell line, although the glycoforms separated with Con A showed slightly different patterns from those separated with LCA. Accordingly, hepatocelluler carcinoma may be detected at an early stage by analyzing the glycoforms of serum AAT and Tf by lectin-affinity electrophoresis for cases with negative AFP.
lectin affinity electrophoresis
cultured hepatoma cell line