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Geel TM, Ruiters MHJ, Cool RH, Halby L, Voshart DC, Andrade Ruiz L, Niezen-Koning KE, Arimondo PB, Rots MG. The past and presence of gene targeting: from chemicals and DNA via proteins to RNA. Philos Trans R Soc Lond B Biol Sci 2018; 373:20170077. [PMID: 29685979 PMCID: PMC5915719 DOI: 10.1098/rstb.2017.0077] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/28/2017] [Indexed: 12/19/2022] Open
Abstract
The ability to target DNA specifically at any given position within the genome allows many intriguing possibilities and has inspired scientists for decades. Early gene-targeting efforts exploited chemicals or DNA oligonucleotides to interfere with the DNA at a given location in order to inactivate a gene or to correct mutations. We here describe an example towards correcting a genetic mutation underlying Pompe's disease using a nucleotide-fused nuclease (TFO-MunI). In addition to the promise of gene correction, scientists soon realized that genes could be inactivated or even re-activated without inducing potentially harmful DNA damage by targeting transcriptional modulators to a particular gene. However, it proved difficult to fuse protein effector domains to the first generation of programmable DNA-binding agents. The engineering of gene-targeting proteins (zinc finger proteins (ZFPs), transcription activator-like effectors (TALEs)) circumvented this problem. The disadvantage of protein-based gene targeting is that a fusion protein needs to be engineered for every locus. The recent introduction of CRISPR/Cas offers a flexible approach to target a (fusion) protein to the locus of interest using cheap designer RNA molecules. Many research groups now exploit this platform and the first human clinical trials have been initiated: CRISPR/Cas has kicked off a new era of gene targeting and is revolutionizing biomedical sciences.This article is part of a discussion meeting issue 'Frontiers in epigenetic chemical biology'.
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Affiliation(s)
- T M Geel
- Epigenetic Editing, Dept Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - M H J Ruiters
- Epigenetic Editing, Dept Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - R H Cool
- Chemical and Pharmaceutical Biology, University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - L Halby
- CNRS FRE3600 ETaC, bât IBCG, 31062 Toulouse, France
| | - D C Voshart
- Epigenetic Editing, Dept Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - L Andrade Ruiz
- Epigenetic Editing, Dept Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - K E Niezen-Koning
- Laboratory of Metabolic Diseases, Dept Laboratory Medicine, University of Groningen, University Medical Center Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - P B Arimondo
- CNRS FRE3600 ETaC, bât IBCG, 31062 Toulouse, France
| | - M G Rots
- Epigenetic Editing, Dept Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
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2
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Nakano M, Tateishi-Karimata H, Tanaka S, Sugimoto N. Affinity of Molecular Ions for DNA Structures Is Determined by Solvent-Accessible Surface Area. J Phys Chem B 2014; 118:9583-94. [DOI: 10.1021/jp505107g] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
| | | | - Shigenori Tanaka
- Graduate
School of System Informatics, Department of Computational Science, Kobe University, 1-1, Rokkodai, Nada-ku, Kobe 657-8501, Japan
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3
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Hégarat N, Novopashina D, Fokina AA, Boutorine AS, Venyaminova AG, Praseuth D, François JC. Monitoring DNA triplex formation using multicolor fluorescence and application to insulin-like growth factor I promoter downregulation. FEBS J 2014; 281:1417-1431. [DOI: 10.1111/febs.12714] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 12/30/2013] [Accepted: 01/08/2014] [Indexed: 01/01/2023]
Affiliation(s)
- Nadia Hégarat
- Acides nucléiques: dynamique, ciblage et fonctions biologiques; INSERM U565; Paris France
- Département Régulations, développement et diversité moléculaire; MNHN - CNRS UMR7196; Paris France
| | - Darya Novopashina
- Laboratory of RNA Chemistry; Institute of Chemical Biology and Fundamental Medicine; Siberian Division of Russian Academy of Sciences; Novosibirsk Russia
| | - Alesya A. Fokina
- Laboratory of RNA Chemistry; Institute of Chemical Biology and Fundamental Medicine; Siberian Division of Russian Academy of Sciences; Novosibirsk Russia
| | - Alexandre S. Boutorine
- Acides nucléiques: dynamique, ciblage et fonctions biologiques; INSERM U565; Paris France
- Département Régulations, développement et diversité moléculaire; MNHN - CNRS UMR7196; Paris France
| | - Alya G. Venyaminova
- Laboratory of RNA Chemistry; Institute of Chemical Biology and Fundamental Medicine; Siberian Division of Russian Academy of Sciences; Novosibirsk Russia
| | - Danièle Praseuth
- Acides nucléiques: dynamique, ciblage et fonctions biologiques; INSERM U565; Paris France
- Département Régulations, développement et diversité moléculaire; MNHN - CNRS UMR7196; Paris France
| | - Jean-Christophe François
- Acides nucléiques: dynamique, ciblage et fonctions biologiques; INSERM U565; Paris France
- Département Régulations, développement et diversité moléculaire; MNHN - CNRS UMR7196; Paris France
- Sorbonne Universités; UPMC Univ Paris 06; UMR_S 938; CDR Saint Antoine; Paris France
- Faculté de Médecine and Hôpital Saint Antoine; INSERM; UMR_S 938; CDR Saint Antoine; Paris France
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4
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Siu FM, Pommier Y. Sequence selectivity of the cleavage sites induced by topoisomerase I inhibitors: a molecular dynamics study. Nucleic Acids Res 2013; 41:10010-9. [PMID: 24021629 PMCID: PMC3905861 DOI: 10.1093/nar/gkt791] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Topoisomerase IB (Top1) inhibitors, such as camptothecin (CPT), stabilize the Top1-DNA cleavage complex in a DNA sequence-dependent manner. The sequence selectivity of Top1 inhibitors is important for targeting specific genomic sequences of therapeutic value. However, the molecular mechanisms underlying this selectivity remain largely unknown. We performed molecular dynamics simulations to delineate structural, dynamic and energetic features that contribute to the differential sequence selectivity of the Top1 inhibitors. We found the sequence selectivity of CPT to be highly correlated with the drug binding energies, dynamic and structural properties of the linker domain. Chemical insights, gained by per-residue binding energy analysis revealed that the non-polar interaction between CPT and nucleotide at the +1 position of the cleavage site was the major (favorable) contributor to the total binding energy. Mechanistic insights gained by a potential of mean force analysis implicated that the drug dissociation step was associated with the sequence selectivity. Pharmaceutical insights gained by our molecular dynamics analyses explained why LMP-776, an indenoisoquinoline derivative under clinical development at the National Institutes of Health, displays different sequence selectivity when compared with camptothecin and its clinical derivatives.
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Affiliation(s)
- Fung-Ming Siu
- Center for High Performance Computing, Institute of Advanced Computing and Digital Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Boulevard, University Town of Shenzhen, Xili Nanshan, Shenzhen 518055, China, Department of Chemistry and Institutes of Molecular Technology for Drug Discovery and Synthesis, State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong and Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
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5
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Govan JM, Uprety R, Hemphill J, Lively MO, Deiters A. Regulation of transcription through light-activation and light-deactivation of triplex-forming oligonucleotides in mammalian cells. ACS Chem Biol 2012; 7:1247-56. [PMID: 22540192 DOI: 10.1021/cb300161r] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Triplex-forming oligonucleotides (TFOs) are efficient tools to regulate gene expression through the inhibition of transcription. Here, nucleobase-caging technology was applied to the temporal regulation of transcription through light-activated TFOs. Through site-specific incorporation of caged thymidine nucleotides, the TFO:DNA triplex formation is blocked, rendering the TFO inactive. However, after a brief UV irradiation, the caging groups are removed, activating the TFO and leading to the inhibition of transcription. Furthermore, the synthesis and site-specific incorporation of caged deoxycytidine nucleotides within TFO inhibitor sequences was developed, allowing for the light-deactivation of TFO function and thus photochemical activation of gene expression. After UV-induced removal of the caging groups, the TFO forms a DNA dumbbell structure, rendering it inactive, releasing it from the DNA, and activating transcription. These are the first examples of light-regulated TFOs and their application in the photochemical activation and deactivation of gene expression. In addition, hairpin loop structures were found to significantly increase the efficacy of phosphodiester DNA-based TFOs in tissue culture.
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Affiliation(s)
- Jeane M. Govan
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina
27695, United States
| | - Rajendra Uprety
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina
27695, United States
| | - James Hemphill
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina
27695, United States
| | - Mark O. Lively
- Center
for Structural Biology, Wake Forest University School of Medicine, Winston-Salem,
North Carolina 27157, United States
| | - Alexander Deiters
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina
27695, United States
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Fokina AA, Meschaninova MI, Durfort T, Venyaminova AG, François JC. Targeting insulin-like growth factor I with 10-23 DNAzymes: 2'-O-methyl modifications in the catalytic core enhance mRNA cleavage. Biochemistry 2012; 51:2181-91. [PMID: 22352843 DOI: 10.1021/bi201532q] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Insulin-like growth factor I (IGF-I) and its cognate receptor (IGF-1R) contribute to normal cell function and to tumorigenesis. The role of IGF-I signaling in tumor growth has been demonstrated in vivo using nucleic acid-based strategies. Here, we designed the first 10-23 DNAzymes directed against IGF-I mRNA. Unlike antisense approaches and RNA interference that require protein catalysis, DNAzymes catalyze protein-free RNA cleavage. We identified target sequences and measured catalytic properties of differently designed DNAzymes on short synthetic RNA targets and on in vitro transcribed IGF-I mRNA. The most efficient cleavers were then transfected into cells, and their inhibitory effect was analyzed using reporter gene assays. We found that increasing the size of DNAzyme flanking sequences and modifications of the termini with 2'-O-methyl residues improved cleavage rates of target RNAs. Modification of the catalytic loop with six 2'-O-methyl ribonucleotides at nonessential positions increased or decreased catalytic efficiency depending on the mRNA target site. In cells, DNAzymes with 2'-O-methyl-modified catalytic cores and flanking sequences were able to inhibit reporter gene activity because of specific recognition and cleavage of IGF-I mRNA sequences. Mutant DNAzymes with inactive catalytic cores were unable to block reporter gene expression, demonstrating that the RNA cleaving ability of 10-23 DNAzymes contributed to inhibitory mechanisms. Our results show that nuclease-resistant 2'-O-methyl-modified DNAzymes with high catalytic efficiencies are useful for inhibiting IGF-I gene function in cells.
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Affiliation(s)
- Alesya A Fokina
- INSERM, U565, Acides nucléiques: dynamique, ciblage et fonctions biologiques, 75005 Paris, France
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Durfort T, Tkach M, Meschaninova MI, Rivas MA, Elizalde PV, Venyaminova AG, Schillaci R, François JC. Small interfering RNA targeted to IGF-IR delays tumor growth and induces proinflammatory cytokines in a mouse breast cancer model. PLoS One 2012; 7:e29213. [PMID: 22235273 PMCID: PMC3250415 DOI: 10.1371/journal.pone.0029213] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Accepted: 11/22/2011] [Indexed: 12/30/2022] Open
Abstract
Insulin-like growth factor I (IGF-I) and its type I receptor (IGF-IR) play significant roles in tumorigenesis and in immune response. Here, we wanted to know whether an RNA interference approach targeted to IGF-IR could be used for specific antitumor immunostimulation in a breast cancer model. For that, we evaluated short interfering RNA (siRNAs) for inhibition of in vivo tumor growth and immunological stimulation in immunocompetent mice. We designed 2′-O-methyl-modified siRNAs to inhibit expression of IGF-IR in two murine breast cancer cell lines (EMT6, C4HD). Cell transfection of IGF-IR siRNAs decreased proliferation, diminished phosphorylation of downstream signaling pathway proteins, AKT and ERK, and caused a G0/G1 cell cycle block. The IGF-IR silencing also induced secretion of two proinflammatory cytokines, TNF- α and IFN-γ. When we transfected C4HD cells with siRNAs targeting IGF-IR, mammary tumor growth was strongly delayed in syngenic mice. Histology of developing tumors in mice grafted with IGF-IR siRNA treated C4HD cells revealed a low mitotic index, and infiltration of lymphocytes and polymorphonuclear neutrophils, suggesting activation of an antitumor immune response. When we used C4HD cells treated with siRNA as an immunogen, we observed an increase in delayed-type hypersensitivity and the presence of cytotoxic splenocytes against wild-type C4HD cells, indicative of evolving immune response. Our findings show that silencing IGF-IR using synthetic siRNA bearing 2′-O-methyl nucleotides may offer a new clinical approach for treatment of mammary tumors expressing IGF-IR. Interestingly, our work also suggests that crosstalk between IGF-I axis and antitumor immune response can mobilize proinflammatory cytokines.
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Affiliation(s)
- Tiphanie Durfort
- Institut National de la Santé et de la Recherche Médicale (INSERM) U565, Paris, France
- Centre National de la Recherche, Scientifique, UMR 7196; Muséum National d'Histoire Naturelle, Paris, France
| | - Mercedes Tkach
- Instituto de Biología y Medicina Experimental (IBYME), Consejo de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Mariya I. Meschaninova
- Institute of Chemical Biology and Fundamental Medicine - Siberian Division of Russian Academy of Sciences (SB-RAS), Novosibirsk, Russia
| | - Martín A. Rivas
- Instituto de Biología y Medicina Experimental (IBYME), Consejo de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Patricia V. Elizalde
- Instituto de Biología y Medicina Experimental (IBYME), Consejo de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Alya G. Venyaminova
- Institute of Chemical Biology and Fundamental Medicine - Siberian Division of Russian Academy of Sciences (SB-RAS), Novosibirsk, Russia
| | - Roxana Schillaci
- Instituto de Biología y Medicina Experimental (IBYME), Consejo de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Jean-Christophe François
- Institut National de la Santé et de la Recherche Médicale (INSERM) U565, Paris, France
- Centre National de la Recherche, Scientifique, UMR 7196; Muséum National d'Histoire Naturelle, Paris, France
- * E-mail:
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8
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Vekhoff P, Duca M, Guianvarc'h D, Benhida R, Arimondo PB. Sequence-specific base pair mimics are efficient topoisomerase IB inhibitors. Biochemistry 2011; 51:43-51. [PMID: 22124209 DOI: 10.1021/bi2012959] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Topoisomerase IB controls DNA topology by cleaving DNA transiently. This property is used by inhibitors, such as camptothecin, that stabilize, by inhibiting the religation step, the cleavage complex, in which the enzyme is covalently attached to the 3'-phosphate of the cleaved DNA strand. These drugs are used in clinics as antitumor agents. Because three-dimensional structural studies have shown that camptothecin derivatives act as base pair mimics and intercalate between two base pairs in the ternary DNA-topoisomerase-inhibitor complex, we hypothesized that base pairs mimics could act like campthotecin and inhibit the religation reaction after the formation of the topoisomerase I-DNA cleavage complex. We show here that three base pair mimics, nucleobases analogues of the aminophenyl-thiazole family, once targeted specifically to a DNA sequence were potent topoisomerase IB inhibitors. The targeting was achieved through covalent linkage to a sequence-specific DNA ligand, a triplex-forming oligonucleotide, and was necessary to position and keep the nucleobase analogue in the cleavage complex. In the absence of triplex formation, only a weak binding to the DNA and topoisomerase I-mediated DNA cleavage was observed. The three compounds were equally active once conjugated, implying that the intercalation of the nucleobase upon triplex formation is the essential feature for the inhibition activity.
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Affiliation(s)
- Pierre Vekhoff
- CNRS UMR7196, Muséum National d'Histoire Naturelle, 43 rue Cuvier, 75005 Paris, France
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9
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Halby L, Champion C, Sénamaud-Beaufort C, Ajjan S, Drujon T, Rajavelu A, Ceccaldi A, Jurkowska R, Lequin O, Nelson WG, Guy A, Jeltsch A, Guianvarc'h D, Ferroud C, Arimondo PB. Rapid Synthesis of New DNMT Inhibitors Derivatives of Procainamide. Chembiochem 2011; 13:157-65. [DOI: 10.1002/cbic.201100522] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Indexed: 11/06/2022]
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Mazzoccoli G, Tarquini R, Durfort T, Francois JC. Chronodisruption in lung cancer and possible therapeutic approaches. Biomed Pharmacother 2011; 65:500-8. [PMID: 21993005 DOI: 10.1016/j.biopha.2011.06.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Accepted: 06/05/2011] [Indexed: 01/05/2023] Open
Abstract
A customary temporal organization of physiological functions and biological processes is necessary to maintain body homeostasis and an altered body time structure may favour carcinogenesis. There is growing evidence that GH stimulates cancer growth, IGF1 may have a role in carcinogenesis and cancer promotion, GH-IGF1 axis, TRH, TSH, thyroxine, melatonin and cortisol modulate immune cell function and the immune system is often dysfunctional in patients with malignancies. The aim of our study was to evaluate GH-IGF1 axis, hypothalamus-pituitary-thyroid axis, melatonin, cortisol, lymphocyte subsets and IL2 in lung cancer patients. Peripheral blood samples were collected at 4-hour intervals in a 24-hour period from eleven healthy male subjects (age range 35-53 years) and nine male patients suffering from non-small cell lung cancer (age range 43-63 years). In each blood sample, lymphocyte subpopulations (CD3+, CD4+, CD8+, CD16+, CD20+, CD25+, HLA-DR+, γδTcR bearing cells) were analyzed and GH, IGF1, TRH, TSH, FT4, melatonin, cortisol and IL2 were measured. Circadian rhythmicity was evaluated and MESOR, amplitude and acrophase values were compared. In healthy subjects a significant circadian rhythm could be demonstrated with midday peaks for CD8+, CD16+, γδTCR expressing cells and cortisol, and peaks during the night for CD3+, CD4+, GH, TSH and melatonin. A borderline significant rhythm was also observed for CD20+, with a peak late in the evening. IGF1, TRH, FT4 and IL2 values did not show rhythmic variation. In cancer patients a significant circadian rhythm could be demonstrated with diurnal peak for CD16+ and peaks during the night for CD4+ and melatonin. GH, IGF1, TRH, TSH, FT4, cortisol and IL2 values did not show rhythmic variation. MESOR of CD8+ (P<0.0001), CD20+ (P=0.05), γδTCR expressing cells (P=0.01), IGF1 (P<0.001) and TSH (P=0.032) was higher in healthy subjects, whereas MESOR of CD16+ (P<0.0001), CD25+ (P=0.001), GH (P<0.001), TRH (P=0.002), FT4 (P=0.030), cortisol (P=0.01) and IL2 (P=0.02) was higher in cancer patients. Amplitude of circadian variation of γδTCR expressing cells (P=0.01), TSH (P<0.001) and cortisol (P=0.01) was higher in healthy subjects, whereas amplitude of circadian variation of CD4+ was higher in cancer patients (P=0.02). In conclusion, non-small cell lung cancer patients show severe alterations of periodic and quantitative characteristics of neuroendocrine and immune parameters with loss of circadian rhythmicity and internal desynchronization, leading to chronodisruption.
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Affiliation(s)
- Gianluigi Mazzoccoli
- Department of Internal Medicine and Chronobiology Unit, Scientific Institute and Regional General Hospital "Casa Sollievo della Sofferenza", S. Giovanni Rotondo-FG, Italy.
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11
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Le Breton C, Hennion M, Arimondo PB, Hyrien O. Replication-fork stalling and processing at a single psoralen interstrand crosslink in Xenopus egg extracts. PLoS One 2011; 6:e18554. [PMID: 21525992 PMCID: PMC3078125 DOI: 10.1371/journal.pone.0018554] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Accepted: 03/04/2011] [Indexed: 01/17/2023] Open
Abstract
Interstrand crosslink (ICL)-inducing agents block the separation of the two DNA strands. They prevent transcription and replication and are used in clinics for the treatment of cancer and skin diseases. Here, we have introduced a single psoralen ICL at a specific site in plasmid DNA using a triplex-forming-oligonucleotide (TFO)-psoralen conjugate and studied its repair in Xenopus egg extracts that support nuclear assembly and replication of plasmid DNA. Replication forks arriving from either side stalled at the psoralen ICL. In contrast to previous observations with other ICL-inducing agents, the leading strands advanced up to the lesion without any prior pausing. Subsequently, incisions were introduced on one parental strand on both sides of the ICL. These incisions could be detected whether one or both forks reached the ICL. Using small molecule inhibitors, we found that the ATR-Chk1 pathway, but not the ATM-Chk2 pathway, stimulated both the incision step and the subsequent processing of the broken replication intermediates. Our results highlight both similarities and differences in fork stalling and repair induced by psoralen and by other ICL-forming agents.
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Affiliation(s)
- Cyrille Le Breton
- Institut de Biologie de l'Ecole Normale Supérieure, CNRS UMR 8197-Inserm U1024, Paris, France
| | - Magali Hennion
- Institut de Biologie de l'Ecole Normale Supérieure, CNRS UMR 8197-Inserm U1024, Paris, France
- Museum National d'Histoire Naturelle UMR 7196 CNRS-INSERM U565, Paris, France
| | - Paola B. Arimondo
- Museum National d'Histoire Naturelle UMR 7196 CNRS-INSERM U565, Paris, France
| | - Olivier Hyrien
- Institut de Biologie de l'Ecole Normale Supérieure, CNRS UMR 8197-Inserm U1024, Paris, France
- * E-mail:
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Lecosnier S, Cordier C, Simon P, François JC, Saison-Behmoaras TE. A steric blocker of translation elongation inhibits IGF-1R expression and cell transformation. FASEB J 2011; 25:2201-10. [PMID: 21402719 DOI: 10.1096/fj.10-169540] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The insulin-like growth factor 1 receptor (IGF-1R) is involved in transformation, survival, mitogenesis and differentiation. It is overexpressed in many tumors and a validated target for anticancer therapy. In cell-free systems, polypyrimidic peptide nucleic acids (PNAs) can form triplex-like structures with messenger RNAs and halt the ribosomal machinery during the translation elongation. A 17-mer PNA that formed a PNA(2):mRNA complex with a purine-rich sequence located in the coding region of IGF-1R mRNA induced the synthesis of a truncated IGF-1R in vitro. This PNA down-regulated expression of the receptor by 70-80% in prostate cancer cells without affecting insulin receptor expression that exhibits high homology with IGF-1R. Inhibition occurs at the translational level, since the IGF-1R mRNA level measured by quantitative RT-PCR was not affected by PNA treatment. In addition, IGF-1R knockdown by PNA led to an attenuation of phosphorylation of downstream signaling pathways, PI3K/AKT and MAPK, involved in survival and mitogenesis and also to a decrease in cell transformation. Of the steric blockers tested, which included phosphorodiamidate morpholino oligomers and locked nucleic acids, PNA was unique in its ability to form triplex structures with mRNA and to arrest translation elongation.
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Affiliation(s)
- Sabine Lecosnier
- Centre National de la Recherche Scientifique, Muséum National d'Histoire Naturelle, Unité Mixte de Recherche 7196, Paris, France
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13
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Birkedal H, Nielsen PE. Targeted gene correction using psoralen, chlorambucil and camptothecin conjugates of triplex forming peptide nucleic acid (PNA). ARTIFICIAL DNA, PNA & XNA 2011; 2:23-32. [PMID: 21686249 PMCID: PMC3116579 DOI: 10.4161/adna.2.1.15553] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 03/18/2011] [Accepted: 03/22/2011] [Indexed: 05/30/2023]
Abstract
Gene correction activation effects of a small series of triplex forming peptide nucleic acid (PNA) covalently conjugated to the DNA interacting ligands psoralen, chlorambucil and camptothecin targeted proximal to a stop codon mutation in an EGFP reporter gene were studied. A 15-mer homopyrimidine PNA conjugated to the topoisomerase I inhibitor camptothecin was found to increase the frequency of repair domain mediated gene correctional events of the EGFP reporter in an in vitro HeLa cell nuclear extract assay, whereas PNA psoralen or chlorambucil conjugates both of which form covalent and also interstrand crosslinked adducts with dsDNA dramatically decreased the frequency of targeted repair/correction. The PNA conjugates were also studied in mammalian cell lines upon transfection of PNA bound EGFP reporter vector and scoring repair of the EGFP gene by FACS analysis of functional EGFP expression. Consistent with the extract experiments, treatment with adduct forming PNA conjugates (psoralen and chlorambucil) resulted in a decrease in background correction frequencies in transiently transfected cells, whereas unmodified PNA or the PNA-camptothecin conjugate had little or no effect. These results suggest that simple triplex forming PNAs have little effect on proximal gene correctional events whereas PNA conjugates capable of forming DNA adducts and interstrand crosslinks are strong inhibitors. Most interestingly the PNA conjugated to the topoisomerase inhibitor, camptothecin enhanced repair in nuclear extract. Thus the effects and use of camptothecin conjugates in gene targeted repair merit further studies.
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Affiliation(s)
- Henrik Birkedal
- Department of Cellular and Molecular Medicine; Faculty of Health Sciences; The Panum Institute; Copenhagen, Denmark
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