title: Gene expression regulation and cancer.
abstract: Gene expression is mostly controlled at the level of the transcription initiation. The transcription control regions of protein-encoding genes include: the core promoter, where RNA polymerase II binds, the proximal and distal promoter, responsible for gene expression regulation, and the enhancers and silencers. Chromatin represents an additional level of regulation of gene expression. The switching between inactive and active chromatin is closely related to the activity of histone-modifying enzymes and chromatin-remodelling complexes. Transcriptional activation of a gene requires the binding of specific transcription factors to regulatory DNA elements, the opening of the chromatin, the binding of Mediator, and the assembly of the preinitiation complex with RNA polymerase and RNA synthesis initiation. Transcription factors ultimately transduce the proliferation signals elicited by growth factors. Moreover, many human oncogenes encode for transcription factors, and some of them are prevalent in particular neoplasias (e.g., MYC, MLL, PML-RARa). Also, some of the most prominent tumor suppressors (e.g. p53) are transcription factors.
authors.affiliation: Grupo de Biología Molecular del Cáncer. Departamento de Biología Molecular. Unidad de Biomedicina-CSIC. Universidad de Cantabria. Santander. Spain.
authors.forename: M Dolore
authors.initials: MD
authors.lastname: Delgado
authors.forename: Javier
authors.initials: J
authors.lastname: León
mesh_terms: D000818:Animals; D002471:Cell Transformation, Neoplastic / Q000235:genetics; D002843:Chromatin / Q000235:genetics / Q000648:ultrastructure; D019175:DNA Methylation; D012321:DNA-Directed RNA Polymerases / Q000502:physiology; D004742:Enhancer Elements, Genetic / Q000235:genetics; D005786:Gene Expression Regulation; D015972:Gene Expression Regulation, Neoplastic; D020868:Gene Silencing; D016147:Genes, Tumor Suppressor; D006801:Humans; D009363:Neoplasm Proteins / Q000502:physiology; D015513:Oncogene Proteins / Q000502:physiology; D009857:Oncogenes; D011401:Promoter Regions, Genetic / Q000235:genetics; D014157:Transcription Factors / Q000502:physiology; D014158:Transcription, Genetic; D015533:Transcriptional Activation
chemical_list: D002843:Chromatin; D009363:Neoplasm Proteins; D015513:Oncogene Proteins; D014157:Transcription Factors; D012321:DNA-Directed RNA Polymerases