High expression level and nuclear localization of Sam68 are associated with progression and poor prognosis in colorectal cancer

BMC Gastroenterology

Li-Bing Song²  Yan-Qing Ding⁴  Xiu-Ting Chen²  Xiao-Hui Zhao²  Ting-Ting Li⁴  Ling Shi²  Yan-Mei Cui⁴  Zheng-Gen Wang¹  Jun-Ling Liu³  Wen-Ting Liao⁴ 

[1] Department of Gastroenterology, the Second Affiliated Hospital, University of South China, HengYang, Hunan 421000, China;State Key Laboratory of Oncology in Southern China, Department of Experimental Research, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510060, P.R. China;State Key Laboratory of Oncology in South China, Department of Medical Oncology, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510060, China;Department of Pathology, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China

关键词: Colorectal cancer;    Prognosis;    Biomarker;    Sam68;   

Others  :  857704
DOI  :  10.1186/1471-230X-13-126

 received in 2012-08-25, accepted in 2013-08-02,  发布年份 2013

【 摘 要 】

Background

Src-associated in mitosis (Sam68; 68 kDa) has been implicated in the oncogenesis and progression of several human cancers. The aim of this study was to investigate the clinicopathologic significance of Sam68 expression and its subcellular localization in colorectal cancer (CRC).

Methods

Sam68 expression was examined in CRC cell lines, nine matched CRC tissues and adjacent noncancerous tissues using reverse transcription (RT)-PCR, quantitative RT-PCR and Western blotting. Sam68 protein expression and localization were determined in 224 paraffin-embedded archived CRC samples using immunohistochemistry. Statistical analyses were applied to evaluate the clinicopathologic significance.

Results

Sam68 was upregulated in CRC cell lines and CRC, as compared with normal tissues; high Sam68 expression was detected in 120/224 (53.6%) of the CRC tissues. High Sam68 expression correlated significantly with poor differentiation (P = 0.033), advanced T stage (P < 0.001), N stage (P = 0.023) and distant metastasis (P = 0.033). Sam68 nuclear localization correlated significantly with poor differentiation (P = 0.002) and T stage (P =0.021). Patients with high Sam68 expression or Sam68 nuclear localization had poorer overall survival than patients with low Sam68 expression or Sam68 cytoplasmic localization. Patients with high Sam68 expression had a higher risk of recurrence than those with low Sam68 expression.

Conclusions

Overexpression of Sam68 correlated highly with cancer progression and poor differentiation in CRC. High Sam68 expression and Sam68 nuclear localization were associated with poorer overall survival.

【 授权许可】

   
2013 Liao et al.; licensee BioMed Central Ltd.

【 图 表 】

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