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Chan BK, Hanan EJ, Bowman KK, Bryan MC, Burdick D, Chan E, Chen Y, Clausen S, Dela Vega T, Dotson J, Eigenbrot C, Elliott RL, Heald RA, Jackson PS, Knight JD, La H, Lainchbury MD, Malek S, Purkey HE, Schaefer G, Schmidt S, Seward EM, Sideris S, Shao L, Wang S, Yeap SK, Yen I, Yu C, Heffron TP. Discovery of a Noncovalent, Mutant-Selective Epidermal Growth Factor Receptor Inhibitor. J Med Chem 2016; 59:9080-9093. [DOI: 10.1021/acs.jmedchem.6b00995] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Richard L. Elliott
- Charles River
Laboratories, 7/9 Spire Green Centre,
Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
| | - Robert A. Heald
- Charles River
Laboratories, 7/9 Spire Green Centre,
Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
| | - Philip S. Jackson
- Charles River
Laboratories, 7/9 Spire Green Centre,
Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
| | - Jamie D. Knight
- Charles River
Laboratories, 7/9 Spire Green Centre,
Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
| | | | - Michael D. Lainchbury
- Charles River
Laboratories, 7/9 Spire Green Centre,
Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
| | | | | | | | | | - Eileen M. Seward
- Charles River
Laboratories, 7/9 Spire Green Centre,
Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
| | | | | | | | - Siew Kuen Yeap
- Charles River
Laboratories, 7/9 Spire Green Centre,
Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
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Heald R, Bowman KK, Bryan MC, Burdick D, Chan B, Chan E, Chen Y, Clausen S, Dominguez-Fernandez B, Eigenbrot C, Elliott R, Hanan EJ, Jackson P, Knight J, La H, Lainchbury M, Malek S, Mann S, Merchant M, Mortara K, Purkey H, Schaefer G, Schmidt S, Seward E, Sideris S, Shao L, Wang S, Yeap K, Yen I, Yu C, Heffron TP. Correction to Noncovalent Mutant Selective Epidermal Growth Factor Receptor Inhibitors: A Lead Optimization Case Study. J Med Chem 2016; 59:2848. [DOI: 10.1021/acs.jmedchem.6b00301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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3
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Heald R, Bowman KK, Bryan MC, Burdick D, Chan B, Chan E, Chen Y, Clausen S, Dominguez-Fernandez B, Eigenbrot C, Elliott R, Hanan EJ, Jackson P, Knight J, La H, Lainchbury M, Malek S, Mann S, Merchant M, Mortara K, Purkey H, Schaefer G, Schmidt S, Seward E, Sideris S, Shao L, Wang S, Yeap K, Yen I, Yu C, Heffron TP. Noncovalent Mutant Selective Epidermal Growth Factor Receptor Inhibitors: A Lead Optimization Case Study. J Med Chem 2015; 58:8877-95. [PMID: 26455919 DOI: 10.1021/acs.jmedchem.5b01412] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Because of their increased activity against activating mutants, first-generation epidermal growth factor receptor (EGFR) kinase inhibitors have had remarkable success in treating non-small-cell lung cancer (NSCLC) patients, but acquired resistance, through a secondary mutation of the gatekeeper residue, means that clinical responses only last for 8-14 months. Addressing this unmet medical need requires agents that can target both of the most common double mutants: T790M/L858R (TMLR) and T790M/del(746-750) (TMdel). Herein we describe how a noncovalent double mutant selective lead compound was optimized using a strategy focused on the structure-guided increase in potency without added lipophilicity or reduction of three-dimensional character. Following successive rounds of design and synthesis it was discovered that cis-fluoro substitution on 4-hydroxy- and 4-methoxypiperidinyl groups provided synergistic, substantial, and specific potency gain through direct interaction with the enzyme and/or effects on the proximal ligand oxygen atom. Further development of the fluorohydroxypiperidine series resulted in the identification of a pair of diastereomers that showed 50-fold enzyme and cell based selectivity for T790M mutants over wild-type EGFR (wtEGFR) in vitro and pathway knock-down in an in vivo xenograft model.
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Affiliation(s)
- Robert Heald
- Argenta, Early Discovery Charles River , 7/9 Spire Green Centre, Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
| | | | | | | | | | | | | | | | - Belen Dominguez-Fernandez
- Argenta, Early Discovery Charles River , 7/9 Spire Green Centre, Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
| | | | - Richard Elliott
- Argenta, Early Discovery Charles River , 7/9 Spire Green Centre, Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
| | | | - Philip Jackson
- Argenta, Early Discovery Charles River , 7/9 Spire Green Centre, Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
| | - Jamie Knight
- Argenta, Early Discovery Charles River , 7/9 Spire Green Centre, Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
| | | | - Michael Lainchbury
- Argenta, Early Discovery Charles River , 7/9 Spire Green Centre, Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
| | | | - Sam Mann
- Argenta, Early Discovery Charles River , 7/9 Spire Green Centre, Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
| | | | | | | | | | | | - Eileen Seward
- Argenta, Early Discovery Charles River , 7/9 Spire Green Centre, Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
| | | | | | | | - Kuen Yeap
- Argenta, Early Discovery Charles River , 7/9 Spire Green Centre, Flex Meadow, Harlow, Essex CM19 5TR, United Kingdom
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Zheng X, Bair KW, Bauer P, Baumeister T, Bowman KK, Buckmelter AJ, Caligiuri M, Clodfelter KH, Feng Y, Han B, Ho YC, Kley N, Li H, Liang X, Liederer BM, Lin J, Ly J, O'Brien T, Oeh J, Oh A, Reynolds DJ, Sampath D, Sharma G, Skelton N, Smith CC, Tremayne J, Wang L, Wang W, Wang Z, Wu H, Wu J, Xiao Y, Yang G, Yuen PW, Zak M, Dragovich PS. Identification of amides derived from 1H-pyrazolo[3,4-b]pyridine-5-carboxylic acid as potent inhibitors of human nicotinamide phosphoribosyltransferase (NAMPT). Bioorg Med Chem Lett 2013; 23:5488-97. [PMID: 24021463 DOI: 10.1016/j.bmcl.2013.08.074] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Revised: 08/11/2013] [Accepted: 08/15/2013] [Indexed: 12/11/2022]
Abstract
Potent, 1H-pyrazolo[3,4-b]pyridine-containing inhibitors of the human nicotinamide phosphoribosyltransferase (NAMPT) enzyme were identified using structure-based design techniques. Many of these compounds exhibited nanomolar antiproliferation activities against human tumor lines in in vitro cell culture experiments, and a representative example (compound 26) demonstrated encouraging in vivo efficacy in a mouse xenograft tumor model derived from the A2780 cell line. This molecule also exhibited reduced rat retinal exposures relative to a previously studied imidazo-pyridine-containing NAMPT inhibitor. Somewhat surprisingly, compound 26 was only weakly active in vitro against mouse and monkey tumor cell lines even though it was a potent inhibitor of NAMPT enzymes derived from these species. The compound also exhibited only minimal effects on in vivo NAD levels in mice, and these changes were considerably less profound than those produced by an imidazo-pyridine-containing NAMPT inhibitor. The crystal structures of compound 26 and the corresponding PRPP-derived ribose adduct in complex with NAMPT were also obtained.
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Affiliation(s)
- Xiaozhang Zheng
- Forma Therapeutics, Inc., 500 Arsenal Street, Watertown, MA 02472, USA
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5
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Jaiswal BS, Kljavin NM, Stawiski EW, Chan E, Parikh C, Durinck S, Chaudhuri S, Pujara K, Guillory J, Edgar KA, Janakiraman V, Scholz RP, Bowman KK, Lorenzo M, Li H, Wu J, Yuan W, Peters BA, Kan Z, Stinson J, Mak M, Modrusan Z, Eigenbrot C, Firestein R, Stern HM, Rajalingam K, Schaefer G, Merchant MA, Sliwkowski MX, de Sauvage FJ, Seshagiri S. Oncogenic ERBB3 mutations in human cancers. Cancer Cell 2013; 23:603-17. [PMID: 23680147 DOI: 10.1016/j.ccr.2013.04.012] [Citation(s) in RCA: 270] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Revised: 01/30/2013] [Accepted: 04/16/2013] [Indexed: 12/16/2022]
Abstract
The human epidermal growth factor receptor (HER) family of tyrosine kinases is deregulated in multiple cancers either through amplification, overexpression, or mutation. ERBB3/HER3, the only member with an impaired kinase domain, although amplified or overexpressed in some cancers, has not been reported to carry oncogenic mutations. Here, we report the identification of ERBB3 somatic mutations in ~11% of colon and gastric cancers. We found that the ERBB3 mutants transformed colonic and breast epithelial cells in a ligand-independent manner. However, the mutant ERBB3 oncogenic activity was dependent on kinase-active ERBB2. Furthermore, we found that anti-ERBB antibodies and small molecule inhibitors effectively blocked mutant ERBB3-mediated oncogenic signaling and disease progression in vivo.
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Affiliation(s)
- Bijay S Jaiswal
- Department of Molecular Biology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
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Koehler MFT, Bergeron P, Blackwood E, Bowman KK, Chen YH, Deshmukh G, Ding X, Epler J, Lau K, Lee L, Liu L, Ly C, Malek S, Nonomiya J, Oeh J, Ortwine DF, Sampath D, Sideris S, Trinh L, Truong T, Wu J, Pei Z, Lyssikatos JP. Potent, selective, and orally bioavailable inhibitors of the mammalian target of rapamycin kinase domain exhibiting single agent antiproliferative activity. J Med Chem 2012. [PMID: 23199076 DOI: 10.1021/jm301389h] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Selective inhibitors of mammalian target of rapamycin (mTOR) kinase based upon saturated heterocycles fused to a pyrimidine core were designed and synthesized. Each series produced compounds with K(i) < 10 nM for the mTOR kinase and >500-fold selectivity over closely related PI3 kinases. This potency translated into strong pathway inhibition, as measured by phosphorylation of mTOR substrate proteins and antiproliferative activity in cell lines with a constitutively active PI3K pathway. Two compounds exhibiting suitable mouse PK were profiled in in vivo tumor models and were shown to suppress mTORC1 and mTORC2 signaling for over 12 h when dosed orally. Both compounds were additionally shown to suppress tumor growth in vivo in a PC3 prostate cancer model over a 14 day study.
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Affiliation(s)
- Michael F T Koehler
- Department of Discovery Chemistry, Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, USA.
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7
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de Leon-Boenig G, Bowman KK, Feng JA, Crawford T, Everett C, Franke Y, Oh A, Stanley M, Staben ST, Starovasnik MA, Wallweber HJA, Wu J, Wu LC, Johnson AR, Hymowitz SG. The crystal structure of the catalytic domain of the NF-κB inducing kinase reveals a narrow but flexible active site. Structure 2012; 20:1704-14. [PMID: 22921830 DOI: 10.1016/j.str.2012.07.013] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 07/20/2012] [Accepted: 07/23/2012] [Indexed: 11/18/2022]
Abstract
The NF-κB inducing kinase (NIK) regulates the non-canonical NF-κB pathway downstream of important clinical targets including BAFF, RANKL, and LTβ. Despite numerous genetic studies associating dysregulation of this pathway with autoimmune diseases and hematological cancers, detailed molecular characterization of this central signaling node has been lacking. We undertook a systematic cloning and expression effort to generate soluble, well-behaved proteins encompassing the kinase domains of human and murine NIK. Structures of the apo NIK kinase domain from both species reveal an active-like conformation in the absence of phosphorylation. ATP consumption and peptide phosphorylation assays confirm that phosphorylation of NIK does not increase enzymatic activity. Structures of murine NIK bound to inhibitors possessing two different chemotypes reveal conformational flexibility in the gatekeeper residue controlling access to a hydrophobic pocket. Finally, a single amino acid difference affects the ability of some inhibitors to bind murine and human NIK with the same affinity.
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Affiliation(s)
- Gladys de Leon-Boenig
- Department of Structural Biology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
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8
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Cohen F, Bergeron P, Blackwood E, Bowman KK, Chen H, DiPasquale AG, Epler JA, Koehler MFT, Lau K, Lewis C, Liu L, Ly CQ, Malek S, Nonomiya J, Ortwine DF, Pei Z, Robarge KD, Sideris S, Trinh L, Truong T, Wu J, Zhao X, Lyssikatos JP. Potent, Selective, and Orally Bioavailable Inhibitors of Mammalian Target of Rapamycin (mTOR) Kinase Based on a Quaternary Substituted Dihydrofuropyrimidine. J Med Chem 2011; 54:3426-35. [PMID: 21495671 DOI: 10.1021/jm200215y] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | | | | | - Antonio G. DiPasquale
- X-ray Crystallography Facility, University of California Berkeley, 32 Lewis Hall Berkeley, California 94720, United States
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9
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Appleton BA, Wu P, Maloney J, Yin J, Liang WC, Stawicki S, Mortara K, Bowman KK, Elliott JM, Desmarais W, Bazan JF, Bagri A, Tessier-Lavigne M, Koch AW, Wu Y, Watts RJ, Wiesmann C. Structural studies of neuropilin/antibody complexes provide insights into semaphorin and VEGF binding. EMBO J 2007; 26:4902-12. [PMID: 17989695 DOI: 10.1038/sj.emboj.7601906] [Citation(s) in RCA: 173] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2007] [Accepted: 10/08/2007] [Indexed: 01/13/2023] Open
Abstract
Neuropilins (Nrps) are co-receptors for class 3 semaphorins and vascular endothelial growth factors and important for the development of the nervous system and the vasculature. The extracellular portion of Nrp is composed of two domains that are essential for semaphorin binding (a1a2), two domains necessary for VEGF binding (b1b2), and one domain critical for receptor dimerization (c). We report several crystal structures of Nrp1 and Nrp2 fragments alone and in complex with antibodies that selectively block either semaphorin or vascular endothelial growth factor (VEGF) binding. In these structures, Nrps adopt an unexpected domain arrangement in which the a2, b1, and b2 domains form a tightly packed core that is only loosely connected to the a1 domain. The locations of the antibody epitopes together with in vitro experiments indicate that VEGF and semaphorin do not directly compete for Nrp binding. Based upon our structural and functional data, we propose possible models for ligand binding to neuropilins.
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Affiliation(s)
- Brent A Appleton
- Department of Protein Engineering, Genentech, Inc., South San Francisco, CA 94080, USA
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10
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Somoza JR, Zhan H, Bowman KK, Yu L, Mortara KD, Palmer JT, Clark JM, McGrath ME. Crystal Structure of Human Cathepsin V. Biochemistry 2001. [DOI: 10.1021/bi015125a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Bowman KK, Clark J, Yu L, Mortara K, Radika K, Wang J, Zhan H. Expression, purification, and characterization of deglycosylated human pro-prostate-specific antigen. Protein Expr Purif 2000; 20:405-13. [PMID: 11087680 DOI: 10.1006/prep.2000.1342] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Wild-type and deglycosylated forms of human prostate-specific antigen were expressed in Chinese hamster ovary (CHO) cells as zymogens. ProPSA was collected from conditioned medium and purified using a single cation-exchange chromatographic step for the deglycosylated form and cation-exchange followed by gel filtration chromatography for the wild-type form. Recombinant wild-type proPSA produced in CHO cells has an average MW of 34.5 kDa, whereas the deglycosylated proPSA has a MW of 32.4 kDa. Both forms of proPSA were activated in vitro and the kinetic properties measured for the deglycosylated PSA are very similar to those of the wild-type recombinant PSA and the native PSA isolated from seminal fluid. These results suggest that deglycosylated PSA is likely to be very similar to native PSA with respect to its three-dimensional structure and will provide a homogeneous protein preparation necessary for X-ray crystallographic analysis.
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Affiliation(s)
- K K Bowman
- Department of Protein Expression, Axys Pharmaceuticals, Inc., 180 Kimball Way, South San Francisco, California 94080, USA
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Abstract
Cathepsin V is a lysosomal cysteine protease that is expressed in the thymus, testis and corneal epithelium. We have determined the 1.6 A resolution crystal structure of human cathepsin V associated with an irreversible vinyl sulfone inhibitor. The fold of this enzyme is similar to the fold adopted by other members of the papain superfamily of cysteine proteases. This study provides a framework for understanding the structural basis for cathepsin V's activity and will aid in the design of inhibitors of this enzyme. A comparison of cathepsin V's active site with the active sites of related proteases revealed a number of differences, especially in the S2 and S3 subsites, that could be exploited in identifying specific cathepsin V inhibitors or in identifying inhibitors of other cysteine proteases that would be selective against cathepsin V.
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Affiliation(s)
- J R Somoza
- Axys Pharmaceuticals, Inc., 385 Oyster Point Boulevard, Suite 1, South San Francisco, California 94080, USA.
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Bowman KK, Sicard DM, Ford JM, Hanawalt PC. Reduced global genomic repair of ultraviolet light-induced cyclobutane pyrimidine dimers in simian virus 40-transformed human cells. Mol Carcinog 2000; 29:17-24. [PMID: 11020243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
The p53 tumor-suppressor gene has been implicated in the inducible activation of excision repair of ultraviolet (UV)-induced cyclobutane pyrimidine dimers (CPDs) in human cells. Because the large T antigen (LTAg) of the simian virus 40 (SV40) binds p53 protein and can interfere with its function, it was of interest to study DNA repair in normal human fibroblasts that had been transformed by SV40 compared with that in their nontransformed parental counterparts and to determine whether such transformation attenuated global genomic repair (GGR) of CPDs. Three methods were used to measure GGR in UV-irradiated cells: (i) an immunoassay using monoclonal antibodies specific for CPDs or 6-4 photoproducts (6-4PPs), (ii) zone sedimentation in alkaline sucrose gradients to measure the average DNA strand size after specific nicking at CPD sites in duplex DNA with T4 endonuclease V (TEV), and (iii) Southern hybridization of TEV-treated DNA with strand-specific mRNA probes to assess removal of CPDs from either strand of a defined genetic sequence in an expressed gene. Whereas repair of 6-4PPs was very similar in paired SV40-transformed and primary fibroblasts, GGR of CPDs was significantly reduced in the SV40-transformed cells. In contrast, SV40 transformation did not appreciably affect the efficiency of transcription-coupled repair. These data support the hypothesis that SV40 transformation can result in reduced levels of GGR, most likely because of the inhibition of normal p53 function by LTAg.
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Affiliation(s)
- K K Bowman
- Department of Biological Sciences, Stanford University, Stanford, California 94305-5151, USA
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Bowman KK, Sicard DM, Ford JM, Hanawalt PC. Reduced global genomic repair of ultraviolet light-induced cyclobutane pyrimidine dimers in simian virus 40-transformed human cells. Mol Carcinog 2000. [DOI: 10.1002/1098-2744(200009)29:1<17::aid-mc3>3.0.co;2-e] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Bowman KK, Smith CA, Hanawalt PC. Excision-repair patch lengths are similar for transcription-coupled repair and global genome repair in UV-irradiated human cells. Mutat Res 1997; 385:95-105. [PMID: 9447231 DOI: 10.1016/s0921-8777(97)00029-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We have used the buoyant density shift method to measure excision-repair patch lengths in UV-irradiated repair-proficient human cells and in primary fibroblasts belonging to xeroderma pigmentosum complementation group C (XP-C), in which excision repair of UV-induced photoproducts is dependent upon transcription. The patch size was found to be about 30 nucleotides for both cell types. This agrees with the size of the DNA fragments excised in vitro by the dual incisions of the structure-specific nucleases XPG and ERCC1-XPF. We conclude that the XPC protein is not required to target the excision nucleases to sites of DNA cleavage in transcribed strands of expressed genes or to protect the newly incised DNA from further processing by exonucleases.
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Affiliation(s)
- K K Bowman
- Department of Biological Sciences, Stanford University, CA 94305-5020, USA.
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16
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Bowman KK, Sidik K, Smith CA, Taylor JS, Doetsch PW, Freyer GA. A new ATP-independent DNA endonuclease from Schizosaccharomyces pombe that recognizes cyclobutane pyrimidine dimers and 6-4 photoproducts. Nucleic Acids Res 1994; 22:3026-32. [PMID: 8065916 PMCID: PMC310271 DOI: 10.1093/nar/22.15.3026] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
We have discovered a new DNA endonuclease in the fission yeast Schizosaccharomyces pombe which recognizes cyclobutane pyrimidine dimers and (6-4) pyrimidine-pyrimidone photoproducts. S. pombe DNA endonuclease (SPDE) catalyzes a single ATP-independent incision immediately 5' to the UV photoproduct and generates termini containing 3' hydroxyl and 5' phosphoryl groups. Based on these properties, we propose that SPDE may function in a DNA repair capacity, representing the initial recognition/cleavage step of a DNA excision repair pathway.
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Affiliation(s)
- K K Bowman
- Department of Biochemistry, Emory University School of Medicine, Rollins Research Center, Atlanta, GA 30322
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