RESUMO
Purpose:To investigate palitaxel (Tax) induct io n of apoptosis in human retinoblastoma Y79 cells and the role of Bcl-2 phosphor ylation in the mechanism. Methods:Antiproliferation effects of Tax on Y79 cells were dete rmined by 3H-thymidine incorporation. Apoptosis of the Tax-treated cells was determined by DNA fragmentation analysis. Bcl-2 phosphorylation was determ ined by Western blot analysis. Cell transfection was used in mutant Bcl-2 trans fecting in Y79 cells. Results:After 24 hours treatment with 1 ?mol/L Tax, 3H- thymidine incorporation decreased in Y79 cells and the effects were time and dos e dependent. DNA ladder appeared in DNA fragmantation analysis after 12-24 hour s treatment with Tax. Bcl-2 Phosphorylation was significantly increased in 12- 24 hours treatment with Tax. Bcl-2, a mutant of Bcl-2, blocked Tax activation process. Conclusions:Tax inhibits cell growth and induces apoptosis in h uman Y79 cells, and phosphorylation of Bcl-2 might be involved in this process.