Tumor Biology

, Volume 36, Issue 6, pp 4509–4518 | Cite as

Clinical significance of Sam68 expression in endometrial carcinoma

Research Article

Abstract

Sam68 (Src-associated in mitosis of 68 kDa) is a substrate for tyrosine kinase c-Src during mitosis. The nuclear protein level has been found to be associated with progression and prognosis in various human malignant tumors. The aim of this study is to investigate the clinical value of Sam68 in endometrial carcinoma (EC). Sam68 expression was confirmed by real-time PCR, Western blot, and immunofluorescent assay in primary normal endometrial epithelial cells, endometrial carcinoma cell lines, as well as seven pairs of EC and matched adjacent noncancerous endometrial tissues. Moreover, the protein level of Sam68 was evaluated by immunohistochemistry in a cohort of surgical specimens derived from 131 patients including primary endometrial carcinoma (n = 95), endometrial atypical hyperplasia (precancerous lesions, n = 26), and normal endometria (n = 10). In endometrial cancer cell lines, RNA interfering approach was employed to downregulate Sam68 expression to determine its role in proliferation. Clinicopathological relevance and prognostic associations were examined by statistical analyses. Compared with normal endometrial and endometrial atypical hyperplasia tissues, Sam68 significantly elevated in endometrial cancer samples (P < 0.01), which was negative or low in 37 cases (38.9 %) and high in 58 cases (61.1 %). The high expression of Sam68 was associated with histological grade (P < 0.001), FIGO stage (P = 0.039), and myometrial invasion (P = 0.002). Kaplan–Meier analysis demonstrated that overexpression of Sam68 correlated with shorter overall survival. It is confirmed by univariate and multivariate analysis (P < 0.001 and P = 0.048, respectively). Additionally, we found that Sam68 was highly expressed at both the transcriptional and translational levels in endometrial cancer cell lines (Ishikawa, HEC-1B, AN3CA, KLE, and RL95-2) and siRNA knockdown of Sam68 remarkably inhibited cellular proliferation in in vitro models. Sam68 may be useful prognostic marker for EC, and it plays an important role in promoting the cellular proliferation. Further investigation of Sam68 as a potential therapeutic target for EC patients could be of interest.

Keywords

Sam68 Endometrial carcinoma Proliferation Survival 

Notes

Acknowledgments

This study was supported by grants from the Shanghai Science and Technology Committee Foundation (13ZR1432000) and the Foundation of Shanghai Municipal Health Bureau (YQ 2012-009).

Conflicts of interest

None

Supplementary material

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ESM 1 (DOC 36 kb)
13277_2015_3095_MOESM2_ESM.doc (38 kb)
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13277_2015_3095_MOESM3_ESM.doc (54 kb)
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Copyright information

© International Society of Oncology and BioMarkers (ISOBM) 2015

Authors and Affiliations

  • Qingying Wang
    • 1
  • Yue Li
    • 1
  • Jianhong Zhou
    • 1
  • Jie Liu
    • 1
  • Jinlong Qin
    • 1
  • Feng Xing
    • 1
  • Jiawen Zhang
    • 1
  • Jiajing Cheng
    • 1
  1. 1.Department of Obstetrics and Gynecology, Shanghai Tenth People’s HospitalTongji University School of MedicineShanghaiChina

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