Epigenetic inactivation of secreted frizzled-related protein 2 in esophageal squamous cell carcinoma

作     者：Xiao-Wen Hao Sheng-Tao Zhu Yuan-Long He Peng Li Yong-Jun Wang and Shu-Tian Zhang 

作者机构：Xiao-Wen Hao Sheng-Tao Zhu Yuan-Long He Peng Li Yong-Jun Wang Shu-Tian Zhang Department of Gastroenterology Beijing Friendship Hospital Capital Medical University 10050 Beijing China 

出 版 物：《World Journal of Gastroenterology》 (世界胃肠病学杂志（英文版）)

年 卷 期：2012年第18卷第6期

页      面：532-540页

核心收录：

学科分类：090603[农学-临床兽医学] 0710[理学-生物学] 071010[理学-生物化学与分子生物学] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 09[农学] 0906[农学-兽医学] 

基　　金：Supported by National Natural Science Foundation of China,No. 81050016 Research Fund for the Doctoral Program of Higher Education of China,No. 200800250003 

主　　题：Esophageal squamous cell carcinoma Se-creted frizzled-related protein 2 Methylation Tumor sup-pressor gene Wnt signaling pathway 

摘      要：AIM： To investigate the expression and methylation status of the secreted frizzled-related protein 2 （SFRP2） in esophageal squamous cell carcinoma （ESCC） and ex- plore its role in ESCC ***： Seven ESCC cell lines （KYSE 30, KYSE150, KYSE410, KYSE510, EC109, EC9706 and TE-1） and one immortalized human esophageal epithelial cell line （Het- 1A）, 20 ESCC tissue samples and 20 paired adjacent non-tumor esophageal epithelial tissues were analyzed in this study. Reverse-transcription polymerase chain reaction （RT-PCR） was employed to investigate the expression of SFRP2 in cell lines, primary ESCC tumor tissue, and paired adjacent normal tissue. Methylation status was evaluated by methylation-specific PCR and bisulfite sequencing. The correlation between expres- sion and promoter methylation of the SFRP2 gene was confirmed with treatment of 5-aza-2＇-deoxycytidine. To assess the potential role of SFRP2 in ESCC, we es-tablished stable SFRP2-transfected cells and examined them with regard to cell proliferation, colony formation, apoptosis and cell cycle in vivo and in ***： SFRP2 mRNA was expressed in the im- mortalized normal esophageal epithelial cell line but not in seven ESCC cell lines. By methylation-specific PCR, complete methylation was detected in three cell lines with silenced SFRP2 expression, and extensive methylation was observed in the other four ESCC cell lines. 5-aza-2＇-deoxycytidine could restore the expres- sion of SFRP2 mRNA in the three ESCC cell lines lack- ing SFRP2 expression. SFRP2 mRNA expression was obviously lower in primary ESCC tissue than in adjacent normal tissue （0.939 ± 0.398 vs 1.51 ± 0.399, P 〈 0.01）. SFRP2 methylation was higher in tumor tissue than in paired normal tissue （95% vs 65%, P 〈 0.05）. The DNA methylation status of the SFRP2 correlated inversely with the SFRP2 expression. To assess the potential role of SFRP2 in ESCC, we established stable SFRP2 transfectants and control counterparts by in- troducing pcDN