title: Comparative proteomic analysis reveals differentially expressed proteins regulated by a potential tumor promoter, BRE, in human esophageal carcinoma cells.
abstract: Esophageal tumorigenesis is a complex and cascading process, involving the interaction of many genes and proteins. In this study, we have used the comparative proteomic approach to identify tumor-associated proteins and explore the carcinogenic mechanisms. Two-dimensional electrophoresis (2-DE) and MALDI-TOF MS analysis of esophageal carcinoma and control cells revealed 10 proteins that were upregulated. A further 10 proteins were downregulated. Among these 20 differentially expressed proteins, brain and reproductive organ-expressed (BRE) protein was identified as a potential tumor promoter. It was high expressed by the esophageal carcinoma cells, as confirmed by RT-PCR and immunoblotting. BRE has been reported to be a stress-responsive protein. To gain further insight into its function, BRE expression was silenced in esophageal carcinoma cells using BRE-specific small interference RNA. It was discovered that silencing BRE expression downregulated prohibitin expression, but upregulated tumor-suppressor p53 expression. Furthermore, cyclin A and CDK2 expressions were suppressed suggesting that BRE inhibited cell proliferation. These results implied that BRE plays a significant role in mediating antiapoptotic and proliferative responses in esophageal carcinoma cells.
authors.affiliation: Department of Histology and Embryology, Shantou University Medical College, Shantou, China.
authors.forename: Hai Bin
authors.initials: HB
authors.lastname: Chen
authors.forename: Ke
authors.initials: K
authors.lastname: Pan
authors.forename: Mei Kuen
authors.initials: MK
authors.lastname: Tang
authors.forename: Yiu Loon
authors.initials: YL
authors.lastname: Chui
authors.forename: Ling
authors.initials: L
authors.lastname: Chen
authors.forename: Zhong Jing
authors.initials: ZJ
authors.lastname: Su
authors.forename: Zhong Ying
authors.initials: ZY
authors.lastname: Shen
authors.forename: En Min
authors.initials: EM
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Xie
authors.forename: Kenneth K H
authors.initials: KK
authors.lastname: Lee