Functional role of the Tau protein in epithelial ovarian cancer cells

Aim The microtubule-associated Tau protein is a marker of paclitaxel sensitivity in ovarian cancer. The aim of the present study was to elucidate the function of the Tau protein in epithelial ovarian cancer. Methods The correlation between Tau protein expression and the response to paclitaxel by using several ovarian cancer cell lines was investigated. Results A Western blot showed that the expression level of the Tau protein was the highest in the TOV112D cells. A cell-counting kit showed that the proliferation rates were more inhibited in the cells with down-regulated Tau protein than in the control cells, both with and without paclitaxel treatment. The proliferation rates of the control cells and the TOV112D cells also were compared with Tau protein overexpression. The level of cell proliferation was more inhibited in the cells that overexpressed the Tau protein, compared to the control cells, both with and without paclitaxel treatment. It was shown that both the down-regulation and the overexpression of the Tau protein were related to the inhibition of TOV112D cell proliferation. Early and late apoptosis of the TOV112D cells that were transfected with Tau cDNA plasmid construct or Tau small interfering RNA significantly increased. Conclusion These findings suggest that the molecular targeting of the Tau protein could be a potential treatment for ovarian cancer.