[Expression of human hepatoma associated antigen in relation to the cell cycle].

The expression of human hepatoma associated antigen A25 in relation to the different stages of cell cycle is reported as studied by monoclonal antibody and flow cytometry methods. A25 antigen was found to express all the four human hepatoma cell lines we tested. Hepatoma cell line PUMC-H1 expressed the antigen at higher levels than SMMC-7721 and QGY-7703 whereas BEL-7402 expressed at lower levels. Further studies showed that the cell lines PUMC-H1, SMMC-7721 and QGY-7703 were found to be at the similar stages of cell cycle while QGY-7703 was different from these three cell lines by having more cells in S state but fewer cells in G0-G1 stages. In the same cell line, A25 was expressed during all cell cycle stages though at different levels. It was expressed at the lowest level in G0-G1 stages, a slightly higher level in S stage and the highest in G2-M stage. The results in this paper suggest that the expression of A25 is related to the stage of cell cycle in the same cell line but not related to the stage of cell cycle in different cell lines with similar tissue origin.