Inhibition of Survivin by Adenovirus Vector Enhanced Paclitaxel-induced Apoptosis in Breast Cancer Cells.

BACKGROUND/AIM: Survivin expression has been shown to be associated with cancer progression, poor prognosis, and drug resistance. The aim of this study was to examine whether survivin knock-down could enhance paclitaxel-induced apoptosis in breast cancer cells in vitro.

MATERIALS AND METHODS

MCF-7 cells were infected with an siRNA-expressing adenovirus vector against survivin (Adv-siSurv) or Renilla luciferase as a control (Adv-siRL). After treatment with paclitaxel, cells were analyzed by apoptotic, cell cycle and immunoblotting assays.

RESULTS

Of cells treated with paclitaxel alone, only 20.2±2.08% showed apoptotic features. An increase in the paclitaxel dose was associated with increased survivin expression. In contrast, Adv-siSurv infection resulted in a marked increase in apoptotic cell death in paclitaxel-treated MCF-7 cells (49.9±7.70%). The percentage of cells in the GM phase was lower (23.9±1.64%) in Adv-siSurv-infected cells than that of Adv-siRL-treated cells (40.0±2.43%). Adv-siSurv infection reduced survivin, procaspase-9, and procaspase-3 levels in paclitaxel-treated MCF-7 cells.

CONCLUSION

Loss of survivin expression enhanced paclitaxel-induced apoptosis in MCF-7 breast cancer cells in vitro.