title: The nucleoside analog clitocine is a potent and efficacious readthrough agent.
abstract: Nonsense mutations resulting in a premature stop codon in an open reading frame occur in critical tumor suppressor genes in a large number of the most common forms of cancers and are known to cause or contribute to the progression of disease. Low molecular weight compounds that induce readthrough of nonsense mutations offer a new means of treating patients with genetic disorders or cancers resulting from nonsense mutations. We have identified the nucleoside analog clitocine as a potent and efficacious suppressor of nonsense mutations. We determined that incorporation of clitocine into RNA during transcription is a prerequisite for its readthrough activity; the presence of clitocine in the third position of a premature stop codon directly induces readthrough. We demonstrate that clitocine can induce the production of p53 protein in cells harboring p53 nonsense-mutated alleles. In these cells, clitocine restored production of full-length and functional p53 as evidenced by induced transcriptional activation of downstream p53 target genes, progression of cells into apoptosis, and impeded growth of nonsense-containing human ovarian cancer tumors in xenograft tumor models. Thus, clitocine induces readthrough of nonsense mutations by a previously undescribed mechanism and represents a novel therapeutic modality to treat cancers and genetic diseases caused by nonsense mutations.
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA wfriesen@ptcbio.com.
authors.forename: Westley J
authors.initials: WJ
authors.lastname: Friesen
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Trotta
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Tomizawa
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Jin
authors.initials: J
authors.lastname: Zhuo
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Briana
authors.initials: B
authors.lastname: Johnson
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Jairo
authors.initials: J
authors.lastname: Sierra
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Bijoyita
authors.initials: B
authors.lastname: Roy
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Marla
authors.initials: M
authors.lastname: Weetall
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Jean
authors.initials: J
authors.lastname: Hedrick
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Josephine
authors.initials: J
authors.lastname: Sheedy
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: James
authors.initials: J
authors.lastname: Takasugi
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Young-Choon
authors.initials: YC
authors.lastname: Moon
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Suresh
authors.initials: S
authors.lastname: Babu
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Ramil
authors.initials: R
authors.lastname: Baiazitov
authors.affiliation: Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01655-0122, USA.
authors.forename: John D
authors.initials: JD
authors.lastname: Leszyk
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Davis
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Colacino
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Stuart W
authors.initials: SW
authors.lastname: Peltz
authors.affiliation: PTC Therapeutics, Inc., South Plainfield, New Jersey 07080, USA.
authors.forename: Ellen M
authors.initials: EM
authors.lastname: Welch
mesh_terms: D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D040761:Biomimetic Materials / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*; D045744:Cell Line, Tumor; D018389:Codon, Nonsense / Q000187:drug effects*; D005260:Female; D005663:Furans / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*; D017930:Genes, Reporter; D006801:Humans; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008819:Mice, Nude; D009705:Nucleosides / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D014176:Protein Biosynthesis; D011741:Pyrimidine Nucleosides / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*; D015398:Signal Transduction; D015533:Transcriptional Activation; D047368:Tumor Burden / Q000187:drug effects; D016159:Tumor Suppressor Protein p53 / Q000819:agonists* / Q000235:genetics / Q000378:metabolism; D023041:Xenograft Model Antitumor Assays
chemical_list: D000964:Antimetabolites, Antineoplastic; D018389:Codon, Nonsense; D005663:Furans; D009705:Nucleosides; D011741:Pyrimidine Nucleosides; D016159:Tumor Suppressor Protein p53; C055433:clitocine; D008156:Luciferases
keywords: clitocine; nonsense suppression; nucleoside analog; p53 therapy; readthrough; stop codon