Effect of spindle checkpoint on Akt2-mediated paclitaxel-resistance in A2780 ovarian cancer cells

Abstract

Recent evidence has suggested that Akt2 plays an important role in the protection of cells from paclitaxel (PTX)-induced apoptosis and control of the cell cycle. In addition, some scholars suggested that the PTX sensitivity depends on a functional spindle assembly checkpoint. In the present study, we investigated the role of the Akt2/Bub1 cross-talking in apoptosis and cell cycle after exposure of the A2780 ovarian cancer cells to paclitaxel (PTX). Recombinant expression plasmid WT-Akt2 was transfected into A2780 cells by lipofectamine2000, and then the expression level of Akt2 gene was detected by using RT-PCR and Western blotting. Cell apoptosis and cell cycle were detected by flow cytometry and Hoechst 33342 staining after treatment with PTX. Moreover, we compared the expression level of Bub1 in different groups by Western blotting. Our study showed that up-regulation of Akt2 contributed to A2780 ovarian cancer cells overriding PTX-induced G₂/M arrest, and inhibited Bub1 expression. Our findings might shed light on the molecular mechanism of PTX-induced resistance in ovarian cancer and help develop novel anti-neoplastic strategies.

Keywords

resistance / paclitaxel / ovarian cancer cells / Akt2 / spindle checkpoint

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