2%) than in Tau-positive (52.4%). Our results differ from those obtained in the studies on breast cancer, where co-expression of Tau protein and estrogen receptor was considered as good prognostic factor [8, 11, 15]. This divergence might be caused by Tau significance evaluation in different cancer sites. Hormone-dependent breast cancer is associated with good prognosis and chemo resistance. Tau genes are regulated by estrogens and tamoxifen so Tau protein expression is associated with hormones. On the other

hand, in ER-negative breast cancer patients group prognostic value of Tau protein was not confirmed. In other study prognostic value of Tau protein in breast cancer was not observed [13]. The only independent parameter significantly influencing on OS in multivariate analysis was sensitivity GW-572016 nmr to first-line chemotherapy (HR 22.59; p<0.0001), defined as no progression or recurrent disease in 6 months from the end of treatment. The aim of adjuvant chemotherapy is prolongation of OS

as well as PFS. The effect is possible to achieve if malignancy is prone to drugs. Thus, chemosensitivity is a good prognostic factor. Conclusions Many studies confirm prognostic value of time duration between chemotherapy ending and disease progression in ovarian cancer [16–18]. Everolimus purchase Extension of this period might be caused by tumor susceptibility to cytostatics as well as maximal cytoreduction during surgery. Mechanisms affecting chemosensitivity are complex. Tau expression is a single factor, influencing sensitivity to paclitaxel. Platinum analogue (the other component of standard regimen in ovarian cancer) effectiveness is modified by numerous factors such as epigenic changes in cancer cells, expression of multidrug resistance proteins (for example: P-gp, MRP1, MRP2, LRP), p53 gene mutations and GST-pi increase [19]. The processes are intricate, thus identification of single factors seems to be complicated, especially in polichemotherapy. Better response to paclitaxel related to negative status of Tau protein in primary tumors

in ovarian cancer is conducive to extension of PFS, and therefore to the improvement of prognosis in ovarian cancer patients. Although sample size in our analysis was not great and the data were evaluated retrospectively, the results of our study may direct successive researches in ovarian cancer. Significance of Tau Megestrol Acetate protein expression requires evaluation in prospective studies with larger group of patients, including assessment of the other predictive and prognostic parameters in paclitaxel and platinum-based chemotherapy. Acknowledgements This study was supported by grant from budget resources for science in the years 2010–2011 as a research project. References 1. McGuire WP, Hoskins WJ, Brady MF: Cyclophosphamide and cisplatin compared with paclitaxel and cisplatin in patients with stage III and stage IV ovarian cancer. N Engl J Med 1996, 334:1–6.PubMedCrossRef 2.