The Studies To Anti-tumor Effect And Its Mechanisms Of Arsenic Trioxide Combined With 5-FU On Human Liver Cancer Cell Line SMMC-7721

Objective: To study the effect induced by arsenic trioxide (As₂O₃) alone and combinated with 5-FU on human liver cancer cell line SMMC-7721.Methods: In vitro, human liver cancer cell line SMMC-7721 was treated by As₂O₃ and (or) 5-FU in various concentrations respectively alone or incombination. The effect of cell growth inhibition was assayed by MTT method. Cell apoptosis morphologic changes were examined using inverted microscope and AO/EB staining. The cell apoptosis ratio was detected by Acridine Orange/ethidium bromide (AO/EB) staining and AnnexinV-PI staining. The expression of bcl-2 protein, bax protein and Fas Protein were investigated by immunocytochemistry techniques.Results: As₂O₃ or 5-FU could inhibit the growth of the human liver cancer cell line SMMC-7721, and the inhibitory effect was dose and time dependent (P<0.05 or P<0.01). Compared with As₂O₃ or 5-FU individual drug group, As₂O₃ combined with 5-FU significantly inhibited the growth of SMMC-7721 cells (P<0.05 or P<0.01); The apoptosis morphologic changes of SMMC-7721 cell treated with As₂O₃ and (or) 5-FU were observed through inverted microscope and AO/EB staining; AO/EB staining and AnnexinV-PI staining showed that, both As₂O₃ and 5-FU could induce SMMC-7721 cell apoptosis and the apoptosis ratio was time dependent (P<0.05 or P<0.01). The combination of As₂O₃ and 5-FU could significantly increase the apoptosis ratio (P<0.05 or P<0.01); Flow cytometry showed that the cell cycle was altered, the ratio of G0/G1 phase cell decreased, the portion of S phase cell increase. Compared with the individual drug group, G0/G1 phase cell decreased significantly and S phase cell increased distinctly in the combine group (P<0.01); Immunocytochemistry showed that, bcl-2 expression were downregulated, and bax,Fas expression was upregulated. Compared with the individual groups, the expression of bcl-2 was downregulated and bax,Fas expression were upregulated distinctly significantly(P<0.05 or P<0.01).Conclusion: As₂O₃ or 5-FU could inhibit the growth of human liver cancer cell line SMMC-7721 in a dose-and-time dependent manner. As₂O₃ combined with 5-FU could significantly increase anti-liver cancer effect through synergetic effect; It maybe were its mechanisms inducing apoptosis through downregulating bcl-2 expression and upregulating bax,Fas expression and adjusting cell cycle.