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Journal of Experimental & Clinical Cancer Research

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Open Access 01-12-2010 | Research

Oncogenic role of the chromobox protein CBX7 in gastric cancer

Authors: Xiao-Wei Zhang, Li Zhang, Wei Qin, Xiao-Hong Yao, Lei-Zhen Zheng, Xin Liu, Jin Li, Wei-Jian Guo

Published in: Journal of Experimental & Clinical Cancer Research | Issue 1/2010

Abstract

Background

Chromobox 7 (CBX7) is a Polycomb family protein that extends the lifespan of normal human cells via downregulating the expression of INK4a/ARF tumor suppressor locus. It was found that CBX7 expression was upregulated in lymphoma, but downregulated in some other human malignancies. The role of CBX7 in most types of cancer is still not clear. The purpose of this study is to investigate the role of CBX7 in gastric cancer.

Methods

The expression of CBX7 and its potential target protein p16(INK4a) in gastric cancer cell lines and gastric tumors was assayed by Western blot analysis and immunohistochemistry(IHC). The correlations between CBX7 expression and p16(INK4a), clinicopathological characteristics, and prognosis were analyzed. Gastric cancer cell line SGC-7901 was transfected with CBX7 siRNA expressing plasmids, and the expression of various proteins was analyzed by Western blot analysis. Cellular senescence, anchorage independent growth, and cell migration assays were performed to determine the functional role of CBX7 in gastric cancer cells.

Results

CBX7 was found to be overexpressed in gastric cancer cell lines and gastric tumors. Overexpression of CBX7 in gastric cancer tissues correlated with patients' age, clinical stage and lymph node metastasis. Knockdown of CBX7 expression in gastric cancer cells led to increased cellular senescence, decreased cellular proliferation and migration ability, accompanied by upregulation of p16(INK4a).

Conclusions

CBX7 acts as an oncogene in the carcinogenesis and progression of gastric cancer, and it may regulate tumorigenesis, cell migration and cancer metastasis partially via p16(INK4a) regulatory pathway.

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Title: Oncogenic role of the chromobox protein CBX7 in gastric cancer
Authors: Xiao-Wei Zhang
Li Zhang
Wei Qin
Xiao-Hong Yao
Lei-Zhen Zheng
Xin Liu
Jin Li
Wei-Jian Guo
Publication date: 01-12-2010
Publisher: BioMed Central
Published in: Journal of Experimental & Clinical Cancer Research / Issue 1/2010
Electronic ISSN: 1756-9966
DOI: https://doi.org/10.1186/1756-9966-29-114

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