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Tumor Biology

, Volume 36, Issue 12, pp 9823–9828 | Cite as

Overexpression of SOX2 is involved in paclitaxel resistance of ovarian cancer via the PI3K/Akt pathway

Research Article

Abstract

Paclitaxel is recommended as a first-line chemotherapeutic agent against ovarian cancer, but drug resistance becomes a major limitation of its success clinically. The key molecule or mechanism associated with paclitaxel resistance in ovarian cancer still remains unclear. Sex-determining region Y-box 2 (SOX2) is of vital importance in the regulation of stem cell proliferation and carcinogenesis. The aim of this study was to evaluate the role of SOX2 in ovarian cancer tumorigenesis and paclitaxel resistance. In the present study, the expression of SOX2 was examined by immunohistochemistry (IHC) and real-time PCR in 40 clinical samples and in SKOV3 cells and SKOV3/TAX cells (paclitaxel-resistant human ovarian adenocarcinoma cell line). The effects of SOX2 knockdown on ovarian cancer cell proliferation, migration, and invasion were also studied. The IHC and real-time PCR results showed that the difference of SOX2 expression between ovarian cancer and the adjacent non-tumorous ovarian tissues was statistically significant. Western blot analysis revealed that the PI3K/Akt signaling pathway was inhibited in cells overexpressing SOX2. Western blot analysis showed that the SOX2 protein was overexpressed in paclitaxel-resistant cells and weakly detectable in paclitaxel-sensitive cells. SOX2 silencing significantly potentiated apoptosis induced by paclitaxel in SKOV3-TR with SOX2 knockdown compared to SKOV3-TR transfected with control small interfering RNA (siRNA). Our work indicates SOX2 will become both a rational indicator of ovarian cancer prognosis and a promising target for ovarian cancer gene therapy.

Keywords

Ovarian cancer SOX2 Chemoresistance SKOV3/TAX cells Proliferation Apoptosis 

Notes

Acknowledgments

This paper was supported by the Natural Science Foundation of China (81472324) and the Henan Education Department Science Foundation of China (13HASTIT022).

Conflicts of interest

None

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Copyright information

© International Society of Oncology and BioMarkers (ISOBM) 2015

Authors and Affiliations

  1. 1.Department of Obstetrics and GynecologyZhengzhou University People’s HospitalZhengzhouChina
  2. 2.Scientific Research OfficeThe Affiliated Cancer Hospital Zhengzhou University People’s HospitalZhengzhouChina
  3. 3.Department of Gynecology OncologyThe Affiliated Cancer Hospital Zhengzhou University People’s HospitalZhengzhouChina

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