title: The Rho GTPase RhoE is a p53-regulated candidate tumor suppressor in cancer cells.
abstract: Previous studies have shown that RhoE, an atypical member of the Rho GTPase family, may play an opposite role to RhoA in regulating cell proliferation and invasion. To explore the relationship between RhoE and the malignant phenotypes of human cancer, we have determined the expression patterns of RhoE in varying grade of human cancer tissues and tested the effects of RhoE expression in several RhoE underexpressing cancer cell lines. Systemic immunocytochemistry analyses of gastric, colorectal, lung and breast carcinomas, respectively, showed that RhoE protein expression was significantly decreased in most cancer cases compared with that of adjacent normal tissues. Enhanced RhoE expression could markedly inhibit proliferation, migration and invasion and induce apoptosis of the cancer cells which have relatively low levels of endogenous RhoE expression. Wild-type p53 (wt-p53) could strongly increase RhoE expression in p53-transfected cells. Furthermore, the luciferase assays indicated that wt-p53 significantly enhanced the activities of RhoE promoter compared with mutant p53 (mt-p53) in PC3 cells (p53 null). Collectively, data are presented showing that RhoE may participate in human cancer progression and act as a candidate target of p53, and these findings also strongly suggest that RhoE may be a new candidate tumor suppressor and could serve as a potential target in the gene therapy of cancer.
authors.affiliation: Department of Medical Oncology and Laboratory of Signal Transduction and Molecular Targeting Therapy, West China Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.
authors.forename: Yajie
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Department of Medical Oncology and Laboratory of Signal Transduction and Molecular Targeting Therapy, West China Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.
authors.forename: Jitao
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of Medical Oncology and Laboratory of Signal Transduction and Molecular Targeting Therapy, West China Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Xia
authors.affiliation: Department of Medical Oncology and Laboratory of Signal Transduction and Molecular Targeting Therapy, West China Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.
authors.forename: Xiangzheng
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Medical Oncology and Laboratory of Signal Transduction and Molecular Targeting Therapy, West China Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.
authors.forename: Meng
authors.initials: M
authors.lastname: Qiu
authors.affiliation: Department of Medical Oncology and Laboratory of Signal Transduction and Molecular Targeting Therapy, West China Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.
authors.forename: Juan
authors.initials: J
authors.lastname: Huang
authors.affiliation: Department of Medical Oncology and Laboratory of Signal Transduction and Molecular Targeting Therapy, West China Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.
authors.forename: Surui
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Medical Oncology and Laboratory of Signal Transduction and Molecular Targeting Therapy, West China Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.
authors.forename: Qiulin
authors.initials: Q
authors.lastname: Tang
authors.affiliation: Department of Medical Oncology and Laboratory of Signal Transduction and Molecular Targeting Therapy, West China Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.
authors.forename: Nan
authors.initials: N
authors.lastname: Lang
authors.affiliation: Department of Medical Oncology and Laboratory of Signal Transduction and Molecular Targeting Therapy, West China Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Medical Oncology and Laboratory of Signal Transduction and Molecular Targeting Therapy, West China Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.
authors.forename: Ming
authors.initials: M
authors.lastname: Liu
authors.affiliation: Division of Experimental Hematology and Cancer Biology, Children's Hospital Research Foundation, University of Cincinnati, Cincinnati, OH 45229, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Department of Medical Oncology and Laboratory of Signal Transduction and Molecular Targeting Therapy, West China Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.
authors.forename: Feng
authors.initials: F
authors.lastname: Bi
mesh_terms: D017209:Apoptosis / Q000235:genetics; D002277:Carcinoma / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D009369:Neoplasms / Q000235:genetics* / Q000473:pathology; D016159:Tumor Suppressor Protein p53 / Q000235:genetics* / Q000378:metabolism; D020741:rho GTP-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D020742:rhoA GTP-Binding Protein / Q000235:genetics
chemical_list: D016159:Tumor Suppressor Protein p53; C508705:RND3 protein, human; D020741:rho GTP-Binding Proteins; D020742:rhoA GTP-Binding Protein