Survivin siRNA increases sensitivity of primary cultures of ovarian cancer cells to paclitaxel

This aim of this study was to use ovarian cancer cells shed in ascitic fluid to establish primary cultures and subsequently use it to detect drug resistance to paclitaxel. Survivin siRNA was used to down regulate survivin expression and effect on paclitaxel resistance was also evaluated. Ascitic fluid along with corresponding primary tumor tissue was collected from twenty untreated epithelial ovarian cancer patients. Ten primary cultures were established from ascites obtained from untreated ovarian cancer patients in MCDB 105 and M199 medium (ratio 1:1). Knockdown of survivin was done using siRNA and sensitivity to paclitaxel was evaluated by MTT assay. Grape-like clusters of ovarian cancer cells present in ascites attached and gave a characteristic cobble stone appearance. Treatment with survivin siRNA resulted in a fivefold decrease in survivin expression in primary cultures. Survivin siRNA treatment significantly increased the sensitivity of the primary ovarian cancer cell cultures to paclitaxel. Ascitic cancer cells reflect the molecular profile of tumor and can be used to diagnose resistance to chemotherapy. This study also establishes that high survivin expression is also responsible for resistance to paclitaxel.