title: A mammalian two-hybrid system for adenomatous polyposis coli-mutated colon cancer therapeutics.
abstract: Colon cancer cells frequently lose expression of the tumor suppressor adenomatous polyposis coli (APC). As result, beta-catenin accumulates and activates transcription of Tcf-responsive genes. Here we describe a novel mammalian two-hybrid system that selectively kills APC-mutated cells. This system consists of GAL4/beta-catenin, VP16/Tcf4, and a gene that is transcribed when GAL4 and VP16 associate. In APC-mutated human colon cancer cells, such as SW480, GAL4/beta-catenin accumulates, and in the presence of VP16/Tcf4, induces high levels of expression of the reporter gene. Expression of wild-type APC reduced GAL4/beta-catenin and intact beta-catenin levels and inhibited reporter gene expression. In colon cancer cells such as SW48 that have wild-type APC, GAL4/beta-catenin was degraded, and expression levels of the output gene were low. Replacement of the reporter gene with a suicide gene resulted in selective killing of SW480 cells. This system may be applicable for broader use of gene therapy by targeting diseases that involve protein degradation.
authors.affiliation: Cancer Research Institute, University of California, San Francisco, School of Medicine, 94143-0128, USA.
authors.forename: K
authors.initials: K
authors.lastname: Wakita
authors.forename: O
authors.initials: O
authors.lastname: Tetsu
authors.forename: F
authors.initials: F
authors.lastname: McCormick
mesh_terms: D025601:Adenomatous Polyposis Coli Protein; D003110:Colonic Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000628:therapy; D003598:Cytoskeletal Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D004268:DNA-Binding Proteins; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D017491:Genes, APC / Q000235:genetics*; D015316:Genetic Therapy / Q000379:methods*; D017405:Herpes Simplex Virus Protein Vmw65 / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007668:Kidney / Q000166:cytology / Q000378:metabolism / Q000502:physiology; D009154:Mutation; D012516:Osteosarcoma / Q000235:genetics / Q000378:metabolism; D010957:Plasmids; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D051820:TCF Transcription Factors; D015534:Trans-Activators; D058118:Transcription Factor 7-Like 2 Protein; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D014162:Transfection; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis; D051176:beta Catenin
chemical_list: D025601:Adenomatous Polyposis Coli Protein; C495270:CTNNB1 protein, human; D003598:Cytoskeletal Proteins; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C052130:GAL4 protein, S cerevisiae; D017405:Herpes Simplex Virus Protein Vmw65; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D051820:TCF Transcription Factors; C544894:TCF7L2 protein, human; D015534:Trans-Activators; D058118:Transcription Factor 7-Like 2 Protein; D014157:Transcription Factors; D016159:Tumor Suppressor Protein p53; D051176:beta Catenin