title: Brd4 and HEXIM1: multiple roles in P-TEFb regulation and cancer.
abstract: Bromodomain-containing protein 4 (Brd4) and hexamethylene bisacetamide (HMBA) inducible protein 1 (HEXIM1) are two opposing regulators of the positive transcription elongation factor b (P-TEFb), which is the master modulator of RNA polymerase II during transcriptional elongation. While Brd4 recruits P-TEFb to promoter-proximal chromatins to activate transcription, HEXIM1 sequesters P-TEFb into an inactive complex containing the 7SK small nuclear RNA. Besides regulating P-TEFb's transcriptional activity, recent evidence demonstrates that both Brd4 and HEXIM1 also play novel roles in cell cycle progression and tumorigenesis. Here we will discuss the current knowledge on Brd4 and HEXIM1 and their implication as novel therapeutic options against cancer.
authors.affiliation: State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005, China.
authors.forename: Ruichuan
authors.identifier: 0000-0002-7891-9231
authors.initials: R
authors.lastname: Chen
authors.affiliation: Department of Orthopaedic Surgery, Lawrence J. Ellison Musculoskeletal Research Center, University of California at Davis Medical Center, Sacramento, CA 95817, USA.
authors.forename: Jasper H N
authors.initials: JH
authors.lastname: Yik
authors.affiliation: Expression Engineering Group, Bioprocessing Technology Institute, A∗STAR (Agency for Science, Technology and Research), 20 Biopolis Way, No. 06-01, Singapore 138668.
authors.forename: Qiao Jing
authors.identifier: 0000-0002-2112-8965
authors.initials: QJ
authors.lastname: Lew
authors.affiliation: Expression Engineering Group, Bioprocessing Technology Institute, A∗STAR (Agency for Science, Technology and Research), 20 Biopolis Way, No. 06-01, Singapore 138668 ; Department of Microbiology, National University of Singapore, Block MD4, 5 Science Drive 2, Singapore 117597.
authors.forename: Sheng-Hao
authors.identifier: 0000-0001-9475-8709
authors.initials: SH
authors.lastname: Chao
mesh_terms: D000595:Amino Acid Sequence; D006801:Humans; D008954:Models, Biological; D008969:Molecular Sequence Data; D009369:Neoplasms / Q000378:metabolism*; D042925:Positive Transcriptional Elongation Factor B / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism*; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism*
chemical_list: D016601:RNA-Binding Proteins; D014157:Transcription Factors; D042925:Positive Transcriptional Elongation Factor B