title: SP1 suppresses phorbol 12-myristate 13-acetate induced up-regulation of human regucalcin expression in liver cancer cells.
abstract: There is a growing evidence that regucalcin (RGN) plays a multifunctional role in liver cancer cells. Previous reports showed that the presence of phorbol 12-myristate 13-acetate (PMA) caused a significant increase in RGN mRNA expression and promoter activity in rat hepatoma cells. In this study, we confirmed that human RGN is also up-regulated by PMA treatment independent of translation, and we identified the mechanism by which PMA up-regulates the expression of human RGN via driving SP1 away from a SP1 motif located within -188/-180 of the promoter in HepG2 cells. Overexpression of SP1 dramatically reduces PMA-induced up-regulation of both internal expression of mRNA and promoter activity, whereas knockdown of SP1 has the opposite effect. Therefore, the present study delineates the fundamental elements in the promoter which will be helpful in the future studies on the regulation of RGN expression in liver cancer.
authors.affiliation: Department of Biochemistry and Molecular Biology, Shanghai Jiaotong University School of Medicine, Shanghai 200025, People's Republic of China.
authors.forename: Hong
authors.initials: H
authors.lastname: Xu
authors.forename: Peihua
authors.initials: P
authors.lastname: Ni
authors.forename: Changqiang
authors.initials: C
authors.lastname: Chen
authors.forename: Yuting
authors.initials: Y
authors.lastname: Yao
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Zhao
authors.forename: Guanxiang
authors.initials: G
authors.lastname: Qian
authors.forename: Xianqun
authors.initials: X
authors.lastname: Fan
authors.forename: Shengfang
authors.initials: S
authors.lastname: Ge
mesh_terms: D001483:Base Sequence; D002135:Calcium-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D047369:Chromatin Immunoprecipitation; D015870:Gene Expression; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D056945:Hep G2 Cells; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics* / Q000378:metabolism; D008113:Liver Neoplasms; D049409:Luciferases, Firefly / Q000096:biosynthesis / Q000235:genetics; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D016329:Sp1 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D015854:Up-Regulation / Q000187:drug effects*
chemical_list: D002135:Calcium-Binding Proteins; D047908:Intracellular Signaling Peptides and Proteins; C513323:RGN protein, human; D016329:Sp1 Transcription Factor; D049409:Luciferases, Firefly; D013755:Tetradecanoylphorbol Acetate