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Sarkar M, Tam EM, Jin G, Chin SS, Abulizi A, Sergeeva OA, Lai Z, Teran E, Karp H, Klaskin D, Pels NA, An X, Ziegler J, Yuan C, Hackettt M, Dhindwal S, Fearnley A, Rodriguez J, Matis L, Fine JS, Myers JS. Abstract 2971: EVOLVETM: A novel T cell engager platform with integrated CD2 costimulation engineered for the treatment of immune suppressive tumors. Cancer Res 2023. [DOI: 10.1158/1538-7445.am2023-2971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Abstract
Bispecific antibodies which bind a tumor antigen and the CD3 heterodimer of the T cell receptor to form a synthetic immunological synapse represent a class of T cell engagers that has been clinically validated with the approvals of blinatumomab (Blinctyo®) and mosunetuzumab (Lunsumio®), targeting CD19 and CD20 respectively, for the treatment of B cell acute lymphoblastic leukemia and follicular lymphoma. Despite being a potent class of therapeutics, not all patients respond to therapy. Recent studies into state of blinatumomab-treated T cells highlight exhaustion and the lack of co-stimulation as potential factors in resistance. In solid tumors, the immunosuppressive tumor microenvironment is also a major factor while cytokine release is a safety consideration for all bispecifics that bind CD3 with strong affinity. To address the challenges of CD3 bispecifics, we have developed the EVOLVE™ platform, a trispecific antibody that consists of tumor targeting and attenuated CD3 binding affinity coupled with a CD2 agonist. We show that CD2 costimulation is superior to other pathways in its ability to sustain T cell activation and expansion and cytokine production over repeated cycles of stimulation. By integrating a CD2 agonist with an attenuated CD3 affinity bispecific, we can restore cytolytic potential without concomitant increase in cytokine release as compared to a strong CD3 affinity bispecific. The EVOLVE platform is also capable of inducing tumor cell killing by in vitro exhausted T cells whereas the bispecific did not. In terms of safety, the EVOLVE platform does not induce peripheral T cell activation and cytokine release in PBMCs in the absence of target as compared to CD3 and CD28 agonist antibodies. The superiority of the EVOLVE platform compared to a bispecific was also demonstrated in vivo where we observed 8/8 complete responses in EVOLVE-treated animals whereas the strong CD3 affinity bispecific showed no difference compared to isotype control using a CORL105 lung cancer xenograft model. We believe these experiments recapitulate the continual clinical challenges of using strong CD3 affinity bispecifics while demonstrating the advantages of the EVOLVE platform. Finally, we demonstrate the modular nature of the EVOLVE platform across diverse tumor antigens including B7H4, PSMA, CD20, and a novel squamous tumor antigen ULBP2. Together our data highlight the broad applications of the EVOLVE platform to improve T cell-mediated anti-tumor immunity and suggest its potential as an emerging, first-in-category immunotherapeutic strategy to address unmet medical needs in oncology.
Citation Format: Mohosin Sarkar, Eric M. Tam, Guixian Jin, Shu Shien Chin, Abudukadier Abulizi, Oksana A. Sergeeva, Zengzu Lai, Evelyn Teran, Hayden Karp, Danielle Klaskin, Nana Adjoa Pels, Xingyue An, Jennifer Ziegler, Changqing Yuan, Maria Hackettt, Sonali Dhindwal, Amber Fearnley, Julio Rodriguez, Louis Matis, Jay S. Fine, Jeremy S. Myers. EVOLVETM: A novel T cell engager platform with integrated CD2 costimulation engineered for the treatment of immune suppressive tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2971.
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Affiliation(s)
| | - Eric M. Tam
- 1EvolveImmune Therapeutics, Inc, Branford, CT
| | - Guixian Jin
- 1EvolveImmune Therapeutics, Inc, Branford, CT
| | | | | | | | - Zengzu Lai
- 1EvolveImmune Therapeutics, Inc, Branford, CT
| | | | - Hayden Karp
- 1EvolveImmune Therapeutics, Inc, Branford, CT
| | | | | | - Xingyue An
- 1EvolveImmune Therapeutics, Inc, Branford, CT
| | | | | | | | | | | | | | - Louis Matis
- 1EvolveImmune Therapeutics, Inc, Branford, CT
| | - Jay S. Fine
- 1EvolveImmune Therapeutics, Inc, Branford, CT
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Chin MSS, Sarkar M, Tam E, Abulizi A, Jin G, An X, Teran E, Klaskin DM, Pels NA, Hackett M, Sergeeva OA, Karp H, Rodriguez J, Dhindwal S, Yuan C, Lai Z, Zeiger J, Fearnley A, Matis L, Fine J, Myers JS. Abstract B44: EVOLVE: A novel costimulatory T cell engager platform engineered for the treatment of solid tumors. Cancer Immunol Res 2022. [DOI: 10.1158/2326-6074.tumimm22-b44] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Abstract
CD3-bispecifics are antibody-based therapies that can simultaneously bind to a tumor cell surface antigen and T cells to establish a synapse between the tumor and T cell and activate T cell to induce specific killing of the tumor cell. CD3-bispecifics have demonstrated clinical success in B cell acute lymphoblastic leukemia and follicular lymphoma with approvals of that blinatumomab and mosunetuzumab that target B cell lineage antigens CD19 and CD20, respectively. However, clinical progress in deploying CD3-bispecifics for positive patient outcomes in solid tumors has been slow, due to tumor microenvironmental factors such as induction of T cell exhaustion, as well as the potential of CD3-bispecifics to mediate T cell anergy and dysfunction in the absence of adequate co-stimulation. Here we describe the development and preclinical validation of the EVOLVE platform, a tumor-targeted biologic that induces the formation of a synthetic synapse that simultaneously activates the T cell receptor complex and the CD2 receptor to optimize CD8 T cell effector phenotype and improve tumor cell killing ex vivo and in vivo, compared to matched CD3-bispecifics. We demonstrate that CD2 co-stimulation is superior to other forms of T cell co-stimulation in its ability to promote cytolytic co-stimulation, T cell cytokine production and T cell expansion. Furthermore, CD2 receptor expression is markedly elevated in tumor infiltrating lymphocytes across a broad set of tumor types, relative to the CD28 and 4-1BB costimulatory receptors. EVOLVE-mediated T cell activation is conditionally dependent on tumor antigen binding and can be tuned to promote optimal co-stimulation without increasing cytokine release relative to matched CD3-bispecifics. We also demonstrate the modular nature of the EVOLVE platform across diverse solid tumor antigens including B7H4 (VTCN1), and a novel squamous tumor antigen ULBP2. Our data highlight the broad applications of the EVOLVE platform to improve CD8 T cell-mediated anti-tumor immunity and suggest its potential as an emerging, first-in-category immunotherapeutic strategy to address unmet medical needs in oncology.
Citation Format: Mandy Shu Shien Chin, Mohosin Sarkar, Eric Tam, Abudukadier Abulizi, Guixian Jin, Xingyue An, Evelyn Teran, Danielle M Klaskin, Nana Adjoa Pels, Maria Hackett, Oksana A Sergeeva, Hayden Karp, Julio Rodriguez, Sonali Dhindwal, Changqing Yuan, Zengzu Lai, Jennifer Zeiger, Amber Fearnley, Louis Matis, Jay Fine, Jeremy S Myers. EVOLVE: A novel costimulatory T cell engager platform engineered for the treatment of solid tumors [abstract]. In: Proceedings of the AACR Special Conference: Tumor Immunology and Immunotherapy; 2022 Oct 21-24; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2022;10(12 Suppl):Abstract nr B44.
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Affiliation(s)
| | | | - Eric Tam
- 1EvolveImmune Therapeutics, Branford, CT,
| | | | | | - Xingyue An
- 1EvolveImmune Therapeutics, Branford, CT,
| | | | | | | | | | | | | | | | | | | | - Zengzu Lai
- 1EvolveImmune Therapeutics, Branford, CT,
| | | | | | | | - Jay Fine
- 1EvolveImmune Therapeutics, Branford, CT,
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Maskey RS, Wang F, Lehman E, Wang Y, Emmanuel N, Zhong W, Jin G, Abraham RT, Arndt KT, Myers JS, Mazurek A. Sustained mTORC1 activity during palbociclib-induced growth arrest triggers senescence in ER+ breast cancer cells. Cell Cycle 2020; 20:65-80. [PMID: 33356791 DOI: 10.1080/15384101.2020.1859195] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Palbociclib, a selective CDK4/6 kinase inhibitor, is approved in combination with endocrine therapies for the treatment of advanced estrogen receptor positive (ER+) breast cancer. In pre-clinical cancer models, CDK4/6 inhibitors act primarily as cytostatic agents. In two commonly studied ER+ breast cancer cell lines (MCF7 and T47D), CDK4/6 inhibition drives G1-phase arrest and the acquisition of a senescent-like phenotype, both of which are reversible upon palbociclib withdrawal (incomplete senescence). Here we identify an ER+ breast cancer cell line, CAMA1, in which palbociclib treatment induces irreversible cell cycle arrest and senescence (complete senescence). In stark contrast to T47D and MCF7 cells, mTORC1 activity is not stably suppressed in CAMA1 cells during palbociclib treatment. Importantly, inhibition of mTORC1 signaling either by the mTORC1 inhibitor rapamycin or by knockdown of Raptor, a unique component of mTORC1, during palbociclib treatment of CAMA1 cells blocks the induction of complete senescence. These results indicate that sustained mTORC1 activity promotes complete senescence in ER+ breast cancer cells during CDK4/6 inhibitor-induced cell cycle arrest. Consistent with this mechanism, genetic depletion of TSC2, a negative regulator of mTORC1, in MCF7 cells resulted in sustained mTORC1 activity during palbociclib treatment and evoked a complete senescence response. These findings demonstrate that persistent mTORC1 signaling during palbociclib-induced G1 arrest is a potential liability for ER+ breast cancer cells, and suggest a strategy for novel drug combinations with palbociclib.
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Affiliation(s)
- Reeja S Maskey
- Oncology Research & Development, Pfizer Worldwide Research and Development , Pearl River, NY, USA
| | - Fang Wang
- Oncology Research & Development, Pfizer Worldwide Research and Development , Pearl River, NY, USA
| | - Elyssa Lehman
- Oncology Research & Development, Pfizer Worldwide Research and Development , Pearl River, NY, USA
| | - Yiqun Wang
- Oncology Research & Development, Pfizer Worldwide Research and Development , Pearl River, NY, USA
| | - Natasha Emmanuel
- Oncology Research & Development, Pfizer Worldwide Research and Development , Pearl River, NY, USA
| | - Wenyan Zhong
- Oncology Research & Development, Pfizer Worldwide Research and Development , Pearl River, NY, USA
| | - Guixian Jin
- Oncology Research & Development, Pfizer Worldwide Research and Development , Pearl River, NY, USA
| | - Robert T Abraham
- Oncology Research & Development, Pfizer Worldwide Research and Development , Pearl River, NY, USA
| | - Kim T Arndt
- Oncology Research & Development, Pfizer Worldwide Research and Development , Pearl River, NY, USA
| | - Jeremy S Myers
- Oncology Research & Development, Pfizer Worldwide Research and Development , Pearl River, NY, USA
| | - Anthony Mazurek
- Oncology Research & Development, Pfizer Worldwide Research and Development , Pearl River, NY, USA
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4
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Zhong W, Myers JS, Wang F, Wang K, Lucas J, Rosfjord E, Lucas J, Hooper AT, Yang S, Lemon LA, Guffroy M, May C, Bienkowska JR, Rejto PA. Comparison of the molecular and cellular phenotypes of common mouse syngeneic models with human tumors. BMC Genomics 2020; 21:2. [PMID: 31898484 PMCID: PMC6941261 DOI: 10.1186/s12864-019-6344-3] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 11/27/2019] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The clinical success of immune checkpoint inhibitors demonstrates that reactivation of the human immune system delivers durable responses for some patients and represents an exciting approach for cancer treatment. An important class of preclinical in vivo models for immuno-oncology is immunocompetent mice bearing mouse syngeneic tumors. To facilitate translation of preclinical studies into human, we characterized the genomic, transcriptomic, and protein expression of a panel of ten commonly used mouse tumor cell lines grown in vitro culture as well as in vivo tumors. RESULTS Our studies identified a number of genetic and cellular phenotypic differences that distinguish commonly used mouse syngeneic models in our study from human cancers. Only a fraction of the somatic single nucleotide variants (SNVs) in these common mouse cell lines directly match SNVs in human actionable cancer genes. Some models derived from epithelial tumors have a more mesenchymal phenotype with relatively low T-lymphocyte infiltration compared to the corresponding human cancers. CT26, a colon tumor model, had the highest immunogenicity and was the model most responsive to CTLA4 inhibitor treatment, by contrast to the relatively low immunogenicity and response rate to checkpoint inhibitor therapies in human colon cancers. CONCLUSIONS The relative immunogenicity of these ten syngeneic tumors does not resemble typical human tumors derived from the same tissue of origin. By characterizing the mouse syngeneic models and comparing with their human tumor counterparts, this study contributes to a framework that may help investigators select the model most relevant to study a particular immune-oncology mechanism, and may rationalize some of the challenges associated with translating preclinical findings to clinical studies.
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Affiliation(s)
- Wenyan Zhong
- Oncology Research & Development, Pfizer Worldwide Research and Development, New York, Pearl River, 10965, USA.
| | - Jeremy S Myers
- Oncology Research & Development, Pfizer Worldwide Research and Development, New York, Pearl River, 10965, USA
| | - Fang Wang
- Oncology Research & Development, Pfizer Worldwide Research and Development, New York, Pearl River, 10965, USA
| | - Kai Wang
- Oncology Research & Development, Pfizer Worldwide Research and Development, San Diego, CA, 92121, USA
| | - Justin Lucas
- Oncology Research & Development, Pfizer Worldwide Research and Development, New York, Pearl River, 10965, USA
| | - Edward Rosfjord
- Oncology Research & Development, Pfizer Worldwide Research and Development, New York, Pearl River, 10965, USA
| | - Judy Lucas
- Oncology Research & Development, Pfizer Worldwide Research and Development, New York, Pearl River, 10965, USA
| | - Andrea T Hooper
- Oncology Research & Development, Pfizer Worldwide Research and Development, New York, Pearl River, 10965, USA
| | - Sharon Yang
- Oncology Research & Development, Pfizer Worldwide Research and Development, New York, Pearl River, 10965, USA
| | - Lu Anna Lemon
- Oncology Research & Development, Pfizer Worldwide Research and Development, New York, Pearl River, 10965, USA
| | - Magali Guffroy
- Drug Safety Research and Development, Pfizer Worldwide Research and Development, New York, Pearl River, 10965, USA
| | - Chad May
- Oncology Research & Development, Pfizer Worldwide Research and Development, New York, Pearl River, 10965, USA
| | - Jadwiga R Bienkowska
- Oncology Research & Development, Pfizer Worldwide Research and Development, San Diego, CA, 92121, USA
| | - Paul A Rejto
- Oncology Research & Development, Pfizer Worldwide Research and Development, San Diego, CA, 92121, USA.
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5
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Sung M, Tan X, Lu B, Golas J, Hosselet C, Wang F, Tylaska L, King L, Zhou D, Dushin R, Myers JS, Rosfjord E, Lucas J, Gerber HP, Loganzo F. Caveolae-Mediated Endocytosis as a Novel Mechanism of Resistance to Trastuzumab Emtansine (T-DM1). Mol Cancer Ther 2017; 17:243-253. [PMID: 29054985 DOI: 10.1158/1535-7163.mct-17-0403] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [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: 05/05/2017] [Revised: 09/07/2017] [Accepted: 09/27/2017] [Indexed: 11/16/2022]
Abstract
Trastuzumab emtansine (T-DM1) is an antibody-drug conjugate (ADC) that has demonstrated clinical benefit for patients with HER2+ metastatic breast cancer; however, its clinical activity is limited by inherent or acquired drug resistance. The molecular mechanisms that drive clinical resistance to T-DM1, especially in HER2+ tumors, are not well understood. We used HER2+ cell lines to develop models of T-DM1 resistance using a cyclical dosing schema in which cells received T-DM1 in an "on-off" routine until a T-DM1-resistant population was generated. T-DM1-resistant N87 cells (N87-TM) were cross-resistant to a panel of trastuzumab-ADCs (T-ADCs) with non-cleavable-linked auristatins. N87-TM cells do not have a decrease in HER2 protein levels or an increase in drug transporter protein (e.g., MDR1) expression compared with parental N87 cells. Intriguingly, T-ADCs using auristatin payloads attached via an enzymatically cleavable linker overcome T-DM1 resistance in N87-TM cells. Importantly, N87-TM cells implanted into athymic mice formed T-DM1 refractory tumors that remain sensitive to T-ADCs with cleavable-linked auristatin payloads. Comparative proteomic profiling suggested enrichment in proteins that mediate caveolae formation and endocytosis in the N87-TM cells. Indeed, N87-TM cells internalize T-ADCs into intracellular caveolin-1 (CAV1)-positive puncta and alter their trafficking to the lysosome compared with N87 cells. T-DM1 colocalization into intracellular CAV1-positive puncta correlated with reduced response to T-DM1 in a panel of HER2+ cell lines. Together, these data suggest that caveolae-mediated endocytosis of T-DM1 may serve as a novel predictive biomarker for patient response to T-DM1. Mol Cancer Ther; 17(1); 243-53. ©2017 AACR.
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Affiliation(s)
- Matthew Sung
- Pfizer Inc., Oncology Research and Development, Pearl River, New York.
| | - Xingzhi Tan
- Pfizer Inc., Oncology Research and Development, Pearl River, New York
| | - Bingwen Lu
- Pfizer Inc., Oncology Research and Development, Pearl River, New York
| | - Jonathan Golas
- Pfizer Inc., Oncology Research and Development, Pearl River, New York
| | | | - Fang Wang
- Pfizer Inc., Oncology Research and Development, Pearl River, New York
| | | | - Lindsay King
- Pfizer Inc., Biomedicine Design, Groton, Connecticut
| | - Dahui Zhou
- Pfizer Inc., Worldwide Medicinal Chemistry, Groton, Connecticut
| | - Russell Dushin
- Pfizer Inc., Worldwide Medicinal Chemistry, Groton, Connecticut
| | - Jeremy S Myers
- Pfizer Inc., Oncology Research and Development, Pearl River, New York
| | - Edward Rosfjord
- Pfizer Inc., Oncology Research and Development, Pearl River, New York
| | - Judy Lucas
- Pfizer Inc., Oncology Research and Development, Pearl River, New York
| | | | - Frank Loganzo
- Pfizer Inc., Oncology Research and Development, Pearl River, New York
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6
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Dann SG, Ryskin M, Barsotti AM, Golas J, Shi C, Miranda M, Hosselet C, Lemon L, Lucas J, Karnoub M, Wang F, Myers JS, Garza SJ, Follettie MT, Geles KG, Klippel A, Rollins RA, Fantin VR. Reciprocal regulation of amino acid import and epigenetic state through Lat1 and EZH2. EMBO J 2015; 34:1773-85. [PMID: 25979827 DOI: 10.15252/embj.201488166] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 04/14/2015] [Indexed: 12/26/2022] Open
Abstract
Lat1 (SLC7A5) is an amino acid transporter often required for tumor cell import of essential amino acids (AA) including Methionine (Met). Met is the obligate precursor of S-adenosylmethionine (SAM), the methyl donor utilized by all methyltransferases including the polycomb repressor complex (PRC2)-specific EZH2. Cell populations sorted for surface Lat1 exhibit activated EZH2, enrichment for Met-cycle intermediates, and aggressive tumor growth in mice. In agreement, EZH2 and Lat1 expression are co-regulated in models of cancer cell differentiation and co-expression is observed at the invasive front of human lung tumors. EZH2 knockdown or small-molecule inhibition leads to de-repression of RXRα resulting in reduced Lat1 expression. Our results describe a Lat1-EZH2 positive feedback loop illustrated by AA depletion or Lat1 knockdown resulting in SAM reduction and concomitant reduction in EZH2 activity. shRNA-mediated knockdown of Lat1 results in tumor growth inhibition and points to Lat1 as a potential therapeutic target.
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Affiliation(s)
| | | | | | | | - Celine Shi
- Pfizer Oncology Research Unit, Pearl River, NY, USA
| | | | | | - Luanna Lemon
- Pfizer Oncology Research Unit, Pearl River, NY, USA
| | - Judy Lucas
- Pfizer Oncology Research Unit, Pearl River, NY, USA
| | | | - Fang Wang
- Pfizer Oncology Research Unit, Pearl River, NY, USA
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7
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Loganzo F, Tan X, Sung M, Jin G, Myers JS, Melamud E, Wang F, Diesl V, Follettie MT, Musto S, Lam MH, Hu W, Charati MB, Khandke K, Kim KSK, Cinque M, Lucas J, Graziani E, Maderna A, O'Donnell CJ, Arndt KT, Gerber HP. Tumor cells chronically treated with a trastuzumab-maytansinoid antibody-drug conjugate develop varied resistance mechanisms but respond to alternate treatments. Mol Cancer Ther 2015; 14:952-63. [PMID: 25646013 DOI: 10.1158/1535-7163.mct-14-0862] [Citation(s) in RCA: 139] [Impact Index Per Article: 15.4] [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: 10/03/2014] [Accepted: 01/22/2015] [Indexed: 11/16/2022]
Abstract
Antibody-drug conjugates (ADC) are emerging as clinically effective therapy. We hypothesized that cancers treated with ADCs would acquire resistance mechanisms unique to immunoconjugate therapy and that changing ADC components may overcome resistance. Breast cancer cell lines were exposed to multiple cycles of anti-Her2 trastuzumab-maytansinoid ADC (TM-ADC) at IC80 concentrations followed by recovery. The resistant cells, 361-TM and JIMT1-TM, were characterized by cytotoxicity, proteomic, transcriptional, and other profiling. Approximately 250-fold resistance to TM-ADC developed in 361-TM cells, and cross-resistance was observed to other non-cleavable-linked ADCs. Strikingly, these 361-TM cells retained sensitivity to ADCs containing cleavable mcValCitPABC-linked auristatins. In JIMT1-TM cells, 16-fold resistance to TM-ADC developed, with cross-resistance to other trastuzumab-ADCs. Both 361-TM and JIMT1-TM cells showed minimal resistance to unconjugated mertansine (DM1) and other chemotherapeutics. Proteomics and immunoblots detected increased ABCC1 (MRP1) drug efflux protein in 361-TM cells, and decreased Her2 (ErbB2) in JIMT1-TM cells. Proteomics also showed alterations in various pathways upon chronic exposure to the drug in both cell models. Tumors derived from 361-TM cells grew in mice and were refractory to TM-ADC compared with parental cells. Hence, acquired resistance to trastuzumab-maytansinoid ADC was generated in cultured cancer cells by chronic drug treatment, and either increased ABCC1 protein or reduced Her2 antigen were primary mediators of resistance. These ADC-resistant cell models retain sensitivity to other ADCs or standard-of-care chemotherapeutics, suggesting that alternate therapies may overcome acquired ADC resistance. Mol Cancer Ther; 14(4); 952-63. ©2015 AACR.
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Affiliation(s)
| | | | | | | | | | | | - Fang Wang
- Pfizer Oncology, Pearl River, New York
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8
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Strop P, Liu SH, Dorywalska M, Delaria K, Dushin RG, Tran TT, Ho WH, Farias S, Casas MG, Abdiche Y, Zhou D, Chandrasekaran R, Samain C, Loo C, Rossi A, Rickert M, Krimm S, Wong T, Chin SM, Yu J, Dilley J, Chaparro-Riggers J, Filzen GF, O'Donnell CJ, Wang F, Myers JS, Pons J, Shelton DL, Rajpal A. Location matters: site of conjugation modulates stability and pharmacokinetics of antibody drug conjugates. ACTA ACUST UNITED AC 2013; 20:161-7. [PMID: 23438745 DOI: 10.1016/j.chembiol.2013.01.010] [Citation(s) in RCA: 358] [Impact Index Per Article: 32.5] [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: 11/10/2012] [Revised: 01/02/2013] [Accepted: 01/08/2013] [Indexed: 11/19/2022]
Abstract
Antibody drug conjugates (ADCs) are a therapeutic class offering promise for cancer therapy. The attachment of cytotoxic drugs to antibodies can result in an effective therapy with better safety potential than nontargeted cytotoxics. To understand the role of conjugation site, we developed an enzymatic method for site-specific antibody drug conjugation using microbial transglutaminase. This allowed us to attach diverse compounds at multiple positions and investigate how the site influences stability, toxicity, and efficacy. We show that the conjugation site has significant impact on ADC stability and pharmacokinetics in a species-dependent manner. These differences can be directly attributed to the position of the linkage rather than the chemical instability, as was observed with a maleimide linkage. With this method, it is possible to produce homogeneous ADCs and tune their properties to maximize the therapeutic window.
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Affiliation(s)
- Pavel Strop
- Rinat-Pfizer, 230 East Grand Avenue, South San Francisco, CA 94080, USA.
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9
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Sherrod SD, Myers MV, Li M, Myers JS, Carpenter KL, Maclean B, Maccoss MJ, Liebler DC, Ham AJL. Label-free quantitation of protein modifications by pseudo selected reaction monitoring with internal reference peptides. J Proteome Res 2012; 11:3467-79. [PMID: 22559222 PMCID: PMC3368409 DOI: 10.1021/pr201240a] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
![]()
Liquid chromatography tandem mass spectrometry (LC–MS/MS)
based methods provide powerful tools for the quantitative analysis
of modified proteins. We have developed a label-free approach using
internal reference peptides (IRP) from the target protein for signal
normalization without the need for isotope labeling. Ion-trap mass
spectrometry and pseudo-selected reaction monitoring (pSRM) were used
to acquire full MS/MS and MS3 spectra from target peptides.
Skyline, a widely used software for SRM experiments, was used for
chromatographic ion extraction. Phosphopeptides spiked into a BSA
background yielded concentration response curves with high correlation
coefficients (typically >0.9) and low coefficients of variation
(≤15%)
over a 200-fold concentration range. Stable isotope dilution (SID)
and IRP methods were compared for quantitation of six site-specific
phosphorylations in the epidermal growth factor receptor (EGFR) in
epidermal growth factor-stimulated A431 cells with or without the
addition of EGFR inhibitors cetuximab and gefitinib. Equivalent responses
were observed with both IRP and SID methods, although analyses using
the IRP method typically had higher median CVs (22–31%) than
SID (10–20%). Analyses using both methods were consistent with
immunoblot using site-selective antibodies. The ease of implementation
and the suitability for targeted quantitative comparisons make this
method suitable for broad application in protein biochemistry.
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Affiliation(s)
- Stacy D Sherrod
- Jim Ayers Institute of Precancer Detection and Diagnosis and §Department of Biostatistics, Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine , Nashville, Tennessee 37232, United States
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10
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Ball HL, Zhang B, Riches JJ, Gandhi R, Li J, Rommens JM, Myers JS. Shwachman-Bodian Diamond syndrome is a multi-functional protein implicated in cellular stress responses. Hum Mol Genet 2009; 18:3684-95. [PMID: 19602484 DOI: 10.1093/hmg/ddp316] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Shwachman-Diamond syndrome (SDS; OMIM 260400) results from loss-of-function mutations in the Shwachman-Bodian Diamond syndrome (SBDS) gene. It is a multi-system disorder with clinical features of exocrine pancreatic dysfunction, skeletal abnormalities, bone marrow failure and predisposition to leukemic transformation. Although the cellular functions of SBDS are still unclear, its yeast ortholog has been implicated in ribosome biogenesis. Using affinity capture and mass spectrometry, we have developed an SBDS-interactome and report SBDS binding partners with diverse molecular functions, notably components of the large ribosomal subunit and proteins involved in DNA metabolism. Reciprocal co-immunoprecipitation confirmed the interaction of SBDS with the large ribosomal subunit protein RPL4 and with DNA-PK and RPA70, two proteins with critical roles in DNA repair. Function for SBDS in response to cellular stresses was implicated by demonstrating that SBDS-depleted HEK293 cells are hypersensitive to multiple types of DNA damage as well as chemically induced endoplasmic reticulum stress. Furthermore, using multiple routes to impair translation and mimic the effect of SBDS-depletion, we show that SBDS-dependent hypersensitivity of HEK293 cells to UV irradiation can be distinguished from a role of SBDS in translation. These results indicate functions of SBDS beyond ribosome biogenesis and may provide insight into the poorly understood cancer predisposition of SDS patients.
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Affiliation(s)
- Heather L Ball
- Program in Genetics and Genome Biology, Research Institute, The Hospital for Sick Children, Toronto, Canada
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de Barros DSM, Da Silva RS, Siam GA, Gheith ME, Nunes CM, Lankaranian D, Tittler EH, Myers JS, Spaeth GL. Should an iridectomy be routinely performed as a part of trabeculectomy? Two surgeons' clinical experience. Eye (Lond) 2007; 23:362-7. [PMID: 17992195 DOI: 10.1038/sj.eye.6703034] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To investigate the effects of performing peripheral iridectomy on the outcome of trabeculectomy. METHODS Retrospective chart review of the medical records of 75 patients (75 eyes) who underwent trabeculectomy surgery, with or without peripheral iridectomy, who had been followed for more than 1 year. Data were collected preoperatively, 1 day postoperatively, on days 30-90 postoperatively, and 1-3 years postoperatively. The collected data included visual acuity, intraocular pressure, bleb development, postoperative inflammation, and complications. Thirty-six eyes (48%) had cataract extraction at the time of trabeculectomy. A peripheral iridectomy was performed in 43 cases (57%). Student's t-test was used for the statistical analyses. RESULTS Patients having peripheral iridectomy had more inflammation on days 30-90 than those who did not have peripheral iridectomy performed (in patients having cataract extraction with trabeculectomy (P=0.018) and those not having cataract extraction (P=0.038)). There was no statistically significant difference in intraocular pressure in eyes with or without iridectomy. Postoperative complications were rare in both groups but greater in number in the eyes with peripheral iridectomy. CONCLUSIONS Trabeculectomy performed without peripheral iridectomy appears to be as effective in lowering intraocular pressure as when performed with peripheral iridectomy, but it is a safer procedure, with a lower incidence of postoperative inflammation. It may be an advantage to avoid performing peripheral iridectomy during trabeculectomy in eyes that are not predisposed to postoperative shallowing of the anterior chamber or pupillary block.
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Affiliation(s)
- D S M de Barros
- The Glaucoma Service Department, Wills Eye Institute, Jefferson Medical College, Philadelphia, PA 19107, USA
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12
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Abstract
The ATR-ATRIP kinase complex regulates cellular responses to DNA damage and replication stress. Mass spectrometry was used to identify phosphorylation sites on ATR and ATRIP to understand how the kinase complex is regulated by post-translational modifications. Two novel phosphorylation sites on ATRIP were identified, S224 and S239. Phosphopeptide-specific antibodies to S224 indicate that it is phosphorylated in a cell cycle-dependent manner. S224 matches a consensus site for cyclin-dependent kinase (CDK) phosphorylation and is phosphorylated by CDK2-cyclin A in vitro. S224 phosphorylation in cells is sensitive to CDK2 inhibitors. Mutation of S224 to alanine causes a defect in the ATR-ATRIP-dependent maintenance of the G(2)-M checkpoint to ionizing and UV radiation. Thus, ATRIP is a CDK2 substrate, and CDK2-dependent phosphorylation of S224 regulates the ability of ATR-ATRIP to promote cell cycle arrest in response to DNA damage.
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Affiliation(s)
- Jeremy S. Myers
- Department of Biochemistry, Vanderbilt University, Nashville TN 37232
| | - Runxiang Zhao
- Department of Biochemistry, Vanderbilt University, Nashville TN 37232
| | - Xin Xu
- Department of Biochemistry, Vanderbilt University, Nashville TN 37232
| | - Amy-Joan L. Ham
- Department of Biochemistry and Mass Spectrometry Research Center, Vanderbilt University, Nashville TN 37232
| | - David Cortez
- Department of Biochemistry, Vanderbilt University, Nashville TN 37232
- Correspondence should be addressed to: David Cortez, Ph.D., Department of Biochemistry, Vanderbilt University, 613 Light Hall, 23rd @ Pierce Ave., Nashville, TN 37232, Phone: 615-322-8547, Fax: 615-343-0704,
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13
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Abstract
The ataxia-telangiectasia-mutated (ATM) and ATM- and Rad3-related (ATR) protein kinases are crucial regulatory proteins in genotoxic stress response pathways that pause the cell cycle to permit DNA repair. Here we show that Chk1 phosphorylation in response to hydroxyurea and ultraviolet radiation is ATR-dependent and ATM- and Mre11-independent. In contrast, Chk1 phosphorylation in response to ionizing radiation (IR) is dependent on ATR, ATM, and Mre11. The ATR and ATM/Mre11 pathways are generally thought to be separate with ATM activation occurring early and ATR activation occurring as a late response to double strand breaks. However, we demonstrate that ATR is activated rapidly by IR, and ATM and Mre11 enhance ATR signaling. ATR-ATR-interacting protein recruitment to double strand breaks is less efficient in the absence of ATM and Mre11. Furthermore, IR-induced replication protein A foci formation is defective in ATM- and Mre11-deficient cells. Thus, ATM and Mre11 may stimulate the ATR signaling pathway by converting DNA damage generated by IR into structures that recruit and activate ATR.
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Affiliation(s)
- Jeremy S Myers
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee 37232, USA
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14
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Abstract
The L1Hs preTa subfamily of long interspersed elements (LINEs) originated after the divergence of human and chimpanzee and is therefore found only in the human genome. Thirty-three of the 254 L1Hs preTa elements are polymorphic for the absence/presence of the insertion, making them useful markers for studying human population genetics. The problem of homoplasy, however, can diminish the value of LINEs as phylogenetic and population genetic markers. We examined anomalous orthologous sites in a range of nonhuman primates. Only two cases of other mobile elements inserting near the preintegration sites of L1Hs preTa elements were observed: an AluY insertion in Chlorocebus and an L1PA8 insertion in Aotus. Sequence analysis showed that both elements were clearly distinguishable from their human counterparts. We conclude that L1 elements can continue to be regarded as essentially homoplasy-free genetic characters.
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Affiliation(s)
- Huei Jin Ho
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, 202 Life Sciences Building, Baton Rouge, LA 70803, USA
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15
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Ball HL, Myers JS, Cortez D. ATRIP binding to replication protein A-single-stranded DNA promotes ATR-ATRIP localization but is dispensable for Chk1 phosphorylation. Mol Biol Cell 2005; 16:2372-81. [PMID: 15743907 PMCID: PMC1087242 DOI: 10.1091/mbc.e04-11-1006] [Citation(s) in RCA: 178] [Impact Index Per Article: 9.4] [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: 11/11/2022] Open
Abstract
ATR associates with the regulatory protein ATRIP that has been proposed to localize ATR to sites of DNA damage through an interaction with single-stranded DNA (ssDNA) coated with replication protein A (RPA). We tested this hypothesis and found that ATRIP is required for ATR accumulation at intranuclear foci induced by DNA damage. A domain at the N terminus of ATRIP is necessary and sufficient for interaction with RPA-ssDNA. Deletion of the ssDNA-RPA interaction domain of ATRIP greatly diminished accumulation of ATRIP into foci. However, the ATRIP-RPA-ssDNA interaction is not sufficient for ATRIP recognition of DNA damage. A splice variant of ATRIP that cannot bind to ATR revealed that ATR association is also essential for proper ATRIP localization. Furthermore, the ATRIP-RPA-ssDNA interaction is not absolutely essential for ATR activation because ATR phosphorylates Chk1 in cells expressing only a mutant of ATRIP that does not bind to RPA-ssDNA. These data suggest that binding to RPA-ssDNA is not the essential function of ATRIP in ATR-dependent checkpoint signaling and ATR has an important function in properly localizing the ATR-ATRIP complex.
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Affiliation(s)
- Heather L Ball
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA
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16
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Salem AH, Ray DA, Xing J, Callinan PA, Myers JS, Hedges DJ, Garber RK, Witherspoon DJ, Jorde LB, Batzer MA. Alu elements and hominid phylogenetics. Proc Natl Acad Sci U S A 2003; 100:12787-91. [PMID: 14561894 PMCID: PMC240696 DOI: 10.1073/pnas.2133766100] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.6] [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] [Received: 06/18/2003] [Indexed: 01/12/2023] Open
Abstract
Alu elements have inserted in primate genomes throughout the evolution of the order. One particular Alu lineage (Ye) began amplifying relatively early in hominid evolution and continued propagating at a low level as many of its members are found in a variety of hominid genomes. This study represents the first conclusive application of short interspersed elements, which are considered nearly homoplasy-free, to elucidate the phylogeny of hominids. Phylogenetic analysis of Alu Ye5 elements and elements from several other subfamilies reveals high levels of support for monophyly of Hominidae, tribe Hominini and subtribe Hominina. Here we present the strongest evidence reported to date for a sister relationship between humans and chimpanzees while clearly distinguishing the chimpanzee and human lineages.
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Affiliation(s)
- Abdel-Halim Salem
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, 202 Life Sciences Building, Baton Rouge, LA 70803, USA
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17
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Vincent BJ, Myers JS, Ho HJ, Kilroy GE, Walker JA, Watkins WS, Jorde LB, Batzer MA. Following the LINEs: an analysis of primate genomic variation at human-specific LINE-1 insertion sites. Mol Biol Evol 2003; 20:1338-48. [PMID: 12777507 DOI: 10.1093/molbev/msg146] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [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: 11/14/2022] Open
Abstract
The L1 Ta subfamily of long interspersed elements (LINEs) consists exclusively of human-specific L1 elements. Polymerase chain reaction-based screening in nonhuman primate genomes of the orthologous sites for 249 human L1 Ta elements resulted in the recovery of various types of sequence variants for approximately 12% of these loci. Sequence analysis was employed to capture the nature of the observed variation and to determine the levels of gene conversion and insertion site homoplasy associated with LINE elements. Half of the orthologous loci differed from the predicted sizes due to localized sequence variants that occurred as a result of common mutational processes in ancestral sequences, often including regions containing simple sequence repeats. Additional sequence variation included genomic deletions that occurred upon L1 insertion, as well as successive mobile element insertions that accumulated within a single locus over evolutionary time. Parallel independent mobile element insertions at orthologous loci in distinct species may introduce homoplasy into retroelement-based phylogenetic and population genetic data. We estimate the overall frequency of parallel independent insertion events at L1 insertion sites in seven different primate species to be very low (0.52%). In addition, no cases of insertion site homoplasy involved the integration of a second L1 element at any of the loci, but rather largely involved secondary insertions of Alu elements. No independent mobile element insertion events were found at orthologous loci in the human and chimpanzee genomes. Therefore, L1 insertion polymorphisms appear to be essentially homoplasy free characters well suited for the study of population genetics and phylogenetic relationships within closely related species.
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Affiliation(s)
- Bethaney J Vincent
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, USA
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18
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Abstract
The preTa subfamily of long interspersed elements (LINEs) is characterized by a three base-pair "ACG" sequence in the 3' untranslated region, contains approximately 400 members in the human genome, and has low level of nucleotide divergence with an estimated average age of 2.34 million years old suggesting that expansion of the L1 preTa subfamily occurred just after the divergence of humans and African apes. We have identified 362 preTa L1 elements from the draft human genomic sequence, investigated the genomic characteristics of preTa L1 insertions, and screened individual elements across diverse human populations and various non-human primate species using polymerase chain reaction (PCR) assays to determine the phylogenetic origin and levels of human genomic diversity associated with the L1 elements. All of the preTa L1 elements analyzed by PCR were absent from the orthologous positions in non-human primate genomes with 33 (14%) of the L1 elements being polymorphic with respect to insertion presence or absence in the human genome. The newly identified L1 insertion polymorphisms will prove useful as identical by descent genetic markers for the study of human population genetics. We provide evidence that preTa L1 elements show an integration site preference for genomic regions with low GC content. Computational analysis of the preTa L1 elements revealed that 29% of the elements amenable to complete sequence analysis have apparently escaped 5' truncation and are essentially full-length (approximately 6kb). In all, 29 have two intact open reading frames and may be capable of retrotransposition.
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Affiliation(s)
- Abdel Halim Salem
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, 202 Life Sciences Building, Baton Rouge, LA 70803, USA
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19
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Myers JS, Vincent BJ, Udall H, Watkins WS, Morrish TA, Kilroy GE, Swergold GD, Henke J, Henke L, Moran JV, Jorde LB, Batzer MA. A comprehensive analysis of recently integrated human Ta L1 elements. Am J Hum Genet 2002; 71:312-26. [PMID: 12070800 PMCID: PMC379164 DOI: 10.1086/341718] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.5] [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] [Received: 04/02/2002] [Accepted: 05/09/2002] [Indexed: 11/04/2022] Open
Abstract
The Ta (transcribed, subset a) subfamily of L1 LINEs (long interspersed elements) is characterized by a 3-bp ACA sequence in the 3' untranslated region and contains approximately 520 members in the human genome. Here, we have extracted 468 Ta L1Hs (L1 human specific) elements from the draft human genomic sequence and screened individual elements using polymerase-chain-reaction (PCR) assays to determine their phylogenetic origin and levels of human genomic diversity. One hundred twenty-four of the elements amenable to complete sequence analysis were full length ( approximately 6 kb) and have apparently escaped any 5' truncation. Forty-four of these full-length elements have two intact open reading frames and may be capable of retrotransposition. Sequence analysis of the Ta L1 elements showed a low level of nucleotide divergence with an estimated age of 1.99 million years, suggesting that expansion of the L1 Ta subfamily occurred after the divergence of humans and African apes. A total of 262 Ta L1 elements were screened with PCR-based assays to determine their phylogenetic origin and the level of human genomic variation associated with each element. All of the Ta L1 elements analyzed by PCR were absent from the orthologous positions in nonhuman primate genomes, except for a single element (L1HS72) that was also present in the common (Pan troglodytes) and pygmy (P. paniscus) chimpanzee genomes. Sequence analysis revealed that this single exception is the product of a gene conversion event involving an older preexisting L1 element. One hundred fifteen (45%) of the Ta L1 elements were polymorphic with respect to insertion presence or absence and will serve as identical-by-descent markers for the study of human evolution.
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Affiliation(s)
- Jeremy S. Myers
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, Baton Rouge; Departments of Pathology, Genetics, Biochemistry, and Molecular Biology, Stanley S. Scott Cancer Center, Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Departments of Human Genetics and Internal Medicine, University of Michigan Medical School, Ann Arbor; Division of Molecular Medicine, Department of Medicine, Columbia University, New York; and Institut für Blutgruppenforschung, Cologne
| | - Bethaney J. Vincent
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, Baton Rouge; Departments of Pathology, Genetics, Biochemistry, and Molecular Biology, Stanley S. Scott Cancer Center, Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Departments of Human Genetics and Internal Medicine, University of Michigan Medical School, Ann Arbor; Division of Molecular Medicine, Department of Medicine, Columbia University, New York; and Institut für Blutgruppenforschung, Cologne
| | - Hunt Udall
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, Baton Rouge; Departments of Pathology, Genetics, Biochemistry, and Molecular Biology, Stanley S. Scott Cancer Center, Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Departments of Human Genetics and Internal Medicine, University of Michigan Medical School, Ann Arbor; Division of Molecular Medicine, Department of Medicine, Columbia University, New York; and Institut für Blutgruppenforschung, Cologne
| | - W. Scott Watkins
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, Baton Rouge; Departments of Pathology, Genetics, Biochemistry, and Molecular Biology, Stanley S. Scott Cancer Center, Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Departments of Human Genetics and Internal Medicine, University of Michigan Medical School, Ann Arbor; Division of Molecular Medicine, Department of Medicine, Columbia University, New York; and Institut für Blutgruppenforschung, Cologne
| | - Tammy A. Morrish
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, Baton Rouge; Departments of Pathology, Genetics, Biochemistry, and Molecular Biology, Stanley S. Scott Cancer Center, Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Departments of Human Genetics and Internal Medicine, University of Michigan Medical School, Ann Arbor; Division of Molecular Medicine, Department of Medicine, Columbia University, New York; and Institut für Blutgruppenforschung, Cologne
| | - Gail E. Kilroy
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, Baton Rouge; Departments of Pathology, Genetics, Biochemistry, and Molecular Biology, Stanley S. Scott Cancer Center, Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Departments of Human Genetics and Internal Medicine, University of Michigan Medical School, Ann Arbor; Division of Molecular Medicine, Department of Medicine, Columbia University, New York; and Institut für Blutgruppenforschung, Cologne
| | - Gary D. Swergold
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, Baton Rouge; Departments of Pathology, Genetics, Biochemistry, and Molecular Biology, Stanley S. Scott Cancer Center, Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Departments of Human Genetics and Internal Medicine, University of Michigan Medical School, Ann Arbor; Division of Molecular Medicine, Department of Medicine, Columbia University, New York; and Institut für Blutgruppenforschung, Cologne
| | - Jurgen Henke
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, Baton Rouge; Departments of Pathology, Genetics, Biochemistry, and Molecular Biology, Stanley S. Scott Cancer Center, Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Departments of Human Genetics and Internal Medicine, University of Michigan Medical School, Ann Arbor; Division of Molecular Medicine, Department of Medicine, Columbia University, New York; and Institut für Blutgruppenforschung, Cologne
| | - Lotte Henke
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, Baton Rouge; Departments of Pathology, Genetics, Biochemistry, and Molecular Biology, Stanley S. Scott Cancer Center, Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Departments of Human Genetics and Internal Medicine, University of Michigan Medical School, Ann Arbor; Division of Molecular Medicine, Department of Medicine, Columbia University, New York; and Institut für Blutgruppenforschung, Cologne
| | - John V. Moran
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, Baton Rouge; Departments of Pathology, Genetics, Biochemistry, and Molecular Biology, Stanley S. Scott Cancer Center, Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Departments of Human Genetics and Internal Medicine, University of Michigan Medical School, Ann Arbor; Division of Molecular Medicine, Department of Medicine, Columbia University, New York; and Institut für Blutgruppenforschung, Cologne
| | - Lynn B. Jorde
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, Baton Rouge; Departments of Pathology, Genetics, Biochemistry, and Molecular Biology, Stanley S. Scott Cancer Center, Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Departments of Human Genetics and Internal Medicine, University of Michigan Medical School, Ann Arbor; Division of Molecular Medicine, Department of Medicine, Columbia University, New York; and Institut für Blutgruppenforschung, Cologne
| | - Mark A. Batzer
- Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, Baton Rouge; Departments of Pathology, Genetics, Biochemistry, and Molecular Biology, Stanley S. Scott Cancer Center, Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans; Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City; Departments of Human Genetics and Internal Medicine, University of Michigan Medical School, Ann Arbor; Division of Molecular Medicine, Department of Medicine, Columbia University, New York; and Institut für Blutgruppenforschung, Cologne
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Morrish TA, Gilbert N, Myers JS, Vincent BJ, Stamato TD, Taccioli GE, Batzer MA, Moran JV. DNA repair mediated by endonuclease-independent LINE-1 retrotransposition. Nat Genet 2002; 31:159-65. [PMID: 12006980 DOI: 10.1038/ng898] [Citation(s) in RCA: 322] [Impact Index Per Article: 14.6] [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: 11/09/2022]
Abstract
Long interspersed elements (LINE-1s) are abundant retrotransposons in mammalian genomes that probably retrotranspose by target site-primed reverse transcription (TPRT). During TPRT, the LINE-1 endonuclease cleaves genomic DNA, freeing a 3' hydroxyl that serves as a primer for reverse transcription of LINE-1 RNA by LINE-1 reverse transcriptase. The nascent LINE-1 cDNA joins to genomic DNA, generating LINE-1 structural hallmarks such as frequent 5' truncations, a 3' poly(A)+ tail and variable-length target site duplications (TSDs). Here we describe a pathway for LINE-1 retrotransposition in Chinese hamster ovary (CHO) cells that acts independently of endonuclease but is dependent upon reverse transcriptase. We show that endonuclease-independent LINE-1 retrotransposition occurs at near-wildtype levels in two mutant cell lines that are deficient in nonhomologous end-joining (NHEJ). Analysis of the pre- and post-integration sites revealed that endonuclease-independent retrotransposition results in unusual structures because the LINE-1s integrate at atypical target sequences, are truncated predominantly at their 3' ends and lack TSDs. Moreover, two of nine endonuclease-independent retrotranspositions contained cDNA fragments at their 3' ends that are probably derived from the reverse transcription of endogenous mRNA. Thus, our results suggest that LINE-1s can integrate into DNA lesions, resulting in retrotransposon-mediated DNA repair in mammalian cells.
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Affiliation(s)
- Tammy A Morrish
- Department of Human Genetics, University of Michigan Medical School, 1241 E. Catherine Street, Ann Arbor, Michigan 48105-0618, USA
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21
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Rondeau G, Moreau I, Bézieau S, Petit JL, Heilig R, Fernandez S, Pennarun E, Myers JS, Batzer MA, Moisan JP, Devilder MC. Comprehensive analysis of a large genomic sequence at the putative B-cell chronic lymphocytic leukaemia (B-CLL) tumour suppresser gene locus. Mutat Res 2001; 458:55-70. [PMID: 11691637 DOI: 10.1016/s0027-5107(01)00219-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [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: 11/26/2022]
Abstract
In many haematological diseases, and more particularly in B-cell chronic lymphocytic leukaemia (B-CLL), the existence of a tumour suppressor gene located within the frequently deleted region 13q14.3, has been put forward. A wide candidate region spanning from marker D13S273 to D13S25 has been proposed and an extensive physical map has been constructed by several teams. In this study, we sequenced a minimal core deleted region that we have previously defined and annotated it with flanking available public sequences. Our analysis shows that this region is gene-poor. Furthermore, our work allowed us to identify new alternative transcripts, spanning core regions, of the previously defined candidate genes DLEU1 and DLEU2. Since their putative involvement in B-CLL was controversial, our present study provide support for reconsidering the DLEU1 and DLEU2 genes as B-CLL candidate genes, with a new definition of their organisation and context.
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Affiliation(s)
- G Rondeau
- INSERM U463, Institut de Biologie de l'Hôtel-Dieu, Centre Hospitalier Universitaire, 44093 Cedex, Nantes, France
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22
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Henderer JD, Heeg MC, Spaeth GL, Moster MR, Myers JS, Schmidt CM, Katz LJ, Steinmann WC. A randomized trial of the long-term effects of digital ocular compression in the late postoperative period. J Glaucoma 2001; 10:266-70. [PMID: 11558809 DOI: 10.1097/00061198-200108000-00004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [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: 11/26/2022]
Abstract
PURPOSE To determine whether digital ocular compression is a viable technique to lower intraocular pressure in patients at least 3 months after trabeculectomy. PATIENTS AND METHODS A 6-month prospective, randomized, controlled, single-masked trial of 29 patients who underwent a trabeculectomy at the Glaucoma Service of Wills Eye Hospital. Patients were assigned to two groups: ocular compression or cheekbone compression (control group). The ocular compression group performed compression to the operated eye three times a day in the pattern of 10 seconds of pressure, 5 seconds of rest, and 10 seconds of pressure. Pressure was applied with the index finger through the closed lid to the center of the cornea. Pressure was steady and firm, but not painful. No massaging was performed. The cheekbone compression group applied pressure to the zygomatic arch with an identical style and frequency. RESULTS At 6 months, the change in mean intraocular pressure for the ocular compression group was 0.25 mm Hg compared with -0.44 mm Hg for the control group (P = 0.7). A few patients in both groups experienced large swings in intraocular pressure and mild to moderate discomfort. CONCLUSION Ocular compression had little to no success in the long-term management of increased intraocular pressure in the late postoperative period in this study.
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Affiliation(s)
- J D Henderer
- William and Anna Goldberg Glaucoma Service, Wills Eye Hospital, Thomas Jefferson University School of Medicine, Philadelphia, Pennsylvania 19107, USA.
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Abstract
Given the recent interest in complementary and alternative medicine (CAM), some patients may seek such treatments to supplement their traditional glaucoma management. The prevalence of CAM use for glaucoma is approximately 5%. We reviewed the literature to determine the potential benefit of various alternative treatments. Aside from a temporary osmotic effect from high dose intravenous ascorbic acid, there is no evidence that megavitamin supplementation has a beneficial effect on glaucoma. During exercise, autoregulation in healthy eyes seems to maintain a consistent blood flow rate to the optic nerve despite fluctuations in intraocular pressure (IOP). In a glaucomatous eye, the very modest IOP-lowering that follows exercise may be offset by the initial elevation in IOP that occurs when one first initiates exercise. At this time, there is no evidence to encourage or discourage the use of special diets, acupuncture, relaxation techniques, or therapeutic touch specifically for the treatment of glaucoma. Very little research has been done on the majority of herbal remedies with regard to their treatment of glaucoma. Marijuana can cause a profound lowering of IOP, but the high nonresponse rate, short half life, and significant toxicity are strong indicators that it is not an appropriate therapeutic agent. Ginkgo biloba and some other Chinese herbal remedies do not affect IOP, but may improve blood flow to the optic nerve and, as such, may have a beneficial effect on glaucoma. These agents have recognized toxicities. Although there are some well-designed studies of alternative treatments, many of the recommendations for using alternative treatments are currently unsupported by the data provided.
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Affiliation(s)
- D J Rhee
- Glaucoma Service, Wills Eye Hospital, Thomas Jefferson University, Philadelphia, PA 19107, USA
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Myers JS. Hypersensitivity reaction to paclitaxel: nursing interventions. Clin J Oncol Nurs 2000; 4:161-3. [PMID: 11261096] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Paclitaxel, a mitotic inhibitor, is used to treat a variety of cancers. A significant incidence of paclitaxel-related hypersensitivity reactions (HSRs) occurs because of the diluent used. Premedication with dexamethasone, diphenhydramine, and H2-histamine antagonists has markedly decreased the incidence of HSRs. Paclitaxel-related HSRs should be managed immediately and appropriately by (a) stopping the infusion, (b) administering oxygen, (c) infusing fluids, (d) continuously monitoring blood pressure, pulse, and oxygenation, and (e) initiating standing orders for i.v. corticosteroids and diphenhydramine or other emergency medications. Oncology nurses are key to the rapid recognition and treatment of paclitaxel-related HSRs.
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Affiliation(s)
- J S Myers
- Research Medical Center, c/o 7 East Oncology, 2316 East Meyer Boulevard, Kansas City, MO 64132, USA.
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Myers JS, Kearney K. Emergency. Chemotherapy-induced hypersensitivity reaction. Am J Nurs 2000; 100:53-4. [PMID: 10776352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Affiliation(s)
- J S Myers
- Research Medical Center, Kansas City, MO, USA
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Abstract
OBJECTIVES To evaluate the effectiveness of excisional revision of filtering blebs for hypotony or leakage when more conservative measures have failed. PATIENTS AND METHODS Retrospective review of all patients who underwent excisional revision of a filtering bleb for hypotony (intraocular pressure [IOP] < 5 mm Hg) or leakage during a 3 year period. The revision consisted of excision of the avascular bleb, mobilization of the surrounding conjunctiva, and suturing of the conjunctiva at the limbus. RESULTS Sixteen patients were included in the study. The average age was 66.3 +/- 14.8 years (range, 39-83). Revision followed trabeculectomy in 11 cases, combined phacoemulsification-trabeculectomy in three cases, and inadvertent blebs in two cases. Five cases had bleb leaks without hypotony, four cases had hypotony alone, and seven cases had both hypotony and a bleb leak. Average follow-up after bleb revision was 25 +/- 11 months (range, 9-43). Average IOP increased from 3.8 +/- 5.6 mm Hg (range, 0-22) to 11.9 +/- 4.1 mm Hg (range, 3-18), with an average of 1.1 +/- 1.1 medication (range, 0-3). The IOP at the last visit was < 15 mm Hg in all but two patients, with 10 of the 16 patients requiring medications. At the last follow-up examination, visual acuity had improved > or = two lines in nine patients and was reduced two lines in one patient. Five patients had early postoperative limbal wound leaks; resuturing was required in one case. CONCLUSIONS Excisional bleb revision is an effective technique to correct hypotony or leakage after filtering surgery when other methods have failed. Intraocular pressure control is often maintained with the use of medications.
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Affiliation(s)
- J S Myers
- Wills Eye Hospital, Philadelphia, Pennsylvania 19107, USA
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Williams-Evans SA, Myers JS, Evena KR, Call-Schmidt T. The impact of domestic violence on children: an adolescents' story. ABNF J 2000; 11:34-6. [PMID: 11074984] [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] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The authors in this paper illustrate how growing up in a violent household impacts the emotional and psychological development of one college-aged student who confronts her father in a letter about his violent behavior as she was growing up. The Williams Assessment of Unresolved Issues (WAUI) survey instrument is briefly discussed as a tool in gathering data about violent episodes experienced by college-aged students during their childhood.
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Myers JS, Crowley JL. Vestiges of life in the oldest Greenland rocks? A review of early Archean geology in the Godthabsfjord region, and reappraisal of field evidence for > 3850 Ma life on Akilia. Precambrian Res 2000; 103:101-124. [PMID: 11577752 DOI: 10.1016/s0301-9268(00)00089-9] [Citation(s) in RCA: 7] [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] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The Godthåbsfjord region of West Greenland contains the most extensive, best exposed and most intensely studied early Archean rocks on Earth. A geological record has been described of numerous magmatic events between ~3.9 and 3.6 Ga, and evidence of life at >3.85 Ga and ~3.8-3.7 Ga has been proposed from two widely-separated localities. Some of these claims have recently been questioned, and the nature of the best preserved remnants of the oldest known terrestrial volcanic and sedimentary rocks in the Isua greenstone belt are being reinvestigated and substantially reinterpreted. The first part of this article reviews the evolution of geological research and interpretations, outlining the techniques by which the geological history has been determined and the ensuing controversies. The second part re-examines crucial field evidence upon which the antiquity of the oldest terrestrial life is claimed from the island of Akilia.
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Affiliation(s)
- J S Myers
- Department of Earth Sciences, Memorial University of Newfoundland, ST John's, Newfoundland, Canada A1B 3X5.
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Wan Z, Zhang Y, Ma X, King MD, Myers JS, Li X. Vicarious calibration of the moderate-resolution imaging spectroradiometer airborne simulator thermal-infrared channels. Appl Opt 1999; 38:6294-6306. [PMID: 18324156 DOI: 10.1364/ao.38.006294] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We made an experimental vicarious calibration of the Moderate Resolution Imaging Spectroradiometer (MODIS) Airborne Simulator (MAS) thermal infrared (TIR) channel data acquired in the field campaign near Mono Lake, Calif. on 10 March 1998 to demonstrate the advantage of using high-elevation sites in dry atmospheric conditions for vicarious calibration. With three lake-surface sites and one snow-field site, we estimated the MAS noise-equivalent temperature difference as 0.7-1.0 degrees C for bands 30-32 in the 3.68-4.13-microm region and 0.1-0.5 degrees C for bands 42, 45, 46, and 48 in the 8-13.5-microm region. This study shows that the MAS calibration error is within +/-0.4 degrees C in the split-window channels (at 11 and 12 microm) and larger in other TIR channels based on the MAS data over Mono Lake and in situ measurement data over the snow-field site.
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Affiliation(s)
- Z Wan
- Institute for Computational Earth System Science, University of California, Santa Barbara, Santa Barbara, California 93106, USA.
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Yang CB, Freedman SF, Myers JS, Buckley EG, Herndon LW, Allingham RR. Use of latanoprost in the treatment of glaucoma associated with Sturge-Weber syndrome. Am J Ophthalmol 1998; 126:600-2. [PMID: 9780111 DOI: 10.1016/s0002-9394(98)00129-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [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: 11/19/2022]
Abstract
PURPOSE To determine if latanoprost reduces intraocular pressure in eyes with glaucoma associated with Sturge-Weber syndrome. METHODS We conducted a prospective study in which eyes with uncontrolled intraocular pressure associated with Sturge-Weber syndrome were treated with latanoprost 0.005% once daily. All eyes were already receiving at least two other antiglaucoma medications. Intraocular pressure was measured at baseline and after treatment for at least 1 month. All intraocular pressure measurements were taken within 24 hours of drug instillation. RESULTS Six eyes of six patients received latanoprost. Two (28%) of the six eyes demonstrated an intraocular pressure decrease that averaged 8.8 mm Hg. These two responders had juvenile onset glaucoma, whereas the four nonresponders had congenital onset glaucoma. CONCLUSIONS Latanoprost may significantly reduce intraocular pressure in selected patients with glaucoma associated with Sturge-Weber syndrome.
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Affiliation(s)
- C B Yang
- Eye Physician Associates, S.C., Milwaukee, Wisconsin, USA
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Myers JS, Trevisani MG, Imami N, Herndon LW, Wolbarsht ML, Allingham RR, Straub KD, Shields MB. Laser energy reaching the posterior pole during transscleral cyclophotocoagulation. Arch Ophthalmol 1998; 116:488-91. [PMID: 9565047 DOI: 10.1001/archopht.116.4.488] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To measure scattered laser energy reaching the posterior pole during transscleral cyclophotocoagulation. METHODS Transscleral cyclophotocoagulation was performed on 4 cadaver eyes with Nd:YAG noncontact, Nd:YAG contact, and diode contact lasers. Energy was measured with a photodiode through a 7-mm trephined hole in the posterior pole. Average percentage power, average power, and average energy transmission were calculated. American Conference of Governmental Industrial Hygienists (ACGIH) guidelines were used to calculate allowable energy exposures for each laser. RESULTS All 3 lasers transmitted 3% to 5% of the power to the posterior pole. The average energy transmission was 240 to 260 mJ for all lasers. The contact lasers had an average power transmission of 120 mW. The noncontact Nd:YAG laser, with shorter pulse duration, had an average power transmission of 13,000 mW, significantly greater than that of the other lasers. The ACGIH guidelines for allowable energy exposures were 93 mJ for the noncontact Nd:YAG laser, 1300 mJ for the contact Nd:YAG laser, and 440 mJ for the contact diode laser. CONCLUSIONS Three percent to 5% of laser power delivered during cyclophotocoagulation reaches the posterior pole. Exposure energies may approach or exceed ACGIH guidelines. The clinical significance of these findings remains to be shown.
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Affiliation(s)
- J S Myers
- Duke University Eye Center, Duke University, Durham, NC 27710, USA
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Thom SB, Myers JS, Rapuano CJ, Eagle RC, Siepser SB, Gomes JA. Effect of topical anti-transforming growth factor-beta on corneal stromal haze after photorefractive keratectomy in rabbits. J Cataract Refract Surg 1997; 23:1324-30. [PMID: 9423903 DOI: 10.1016/s0886-3350(97)80110-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [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: 02/05/2023]
Abstract
PURPOSE To determine the relationship between anti-transforming growth factor-beta (anti-TGF-beta) antibodies and the amount of corneal stromal haze after excimer laser photorefractive keratectomy (PRK). SETTING Wills Eye Hospital, Philadelphia, Pennsylvania, USA. METHODS Nineteen rabbits had bilateral PRK. Dichlorotriazinyl fluorescein was used to stain the exposed stroma; all rabbits were then treated with antibiotic ointment for 4 days. Ten rabbits were randomized to treatment with topical anti-TGF-beta1, -beta2, and -beta3 antibody 50 microg three times a day for 4 days; the others received diluent three times a day for 4 days. Stromal haze was graded weekly for 8 weeks on a 0 to 4+ scale. At the end of the study, all corneas were examined histopathologically. RESULTS All treated eyes developed appreciable haze. Seven control rabbits and one antibody-treated rabbit had an epithelial erosion (P = .00001). Antibody-treated rabbits had significantly less haze at 3, 4, and 5 weeks (right eyes) and 3, 4, 5, 7 and 8 weeks (left eyes) (P < .05). Histopathology and fluorescence microscopy showed subepithelial collagen deposition consistent with clinical haze. CONCLUSIONS Topical anti-TGF-beta antibody reduced stromal haze after PRK in the rabbit model and may be clinically beneficial in humans.
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Affiliation(s)
- S B Thom
- Cataract and Primary Eye Care Service, Wills Eye Hospital, Philadelphia, Pennsylvania 19107, USA
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Myers JS, Gomes JA, Siepser SB, Rapuano CJ, Eagle RC, Thom SB. Effect of Transforming Growth Factor β1 on Stromal Haze following Excimer Laser Photorefractive Keratectomy in Rabbits. J Refract Surg 1997; 13:356-61. [PMID: 9268935 DOI: 10.3928/1081-597x-19970701-11] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [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: 11/20/2022]
Abstract
BACKGROUND Transforming growth factor beta (TGF-beta) has been shown to affect wound repair. Anti-transforming growth factor beta 1 antibodies have been shown to neutralize its activity. METHODS Seventeen New Zealand White rabbits underwent unilateral photorefractive keratectomy followed by corneal staining with dichlorotriazinyl fluorescein. Three groups received topical transforming growth factor beta 1: 1 microgram/ml, 10 micrograms/ml, and 100 micrograms/ml; one group topical anti-transforming growth factor beta antibody (200 micrograms/ml); and a control group vehicle only. Corneal haze was graded from 0 to 4, weekly. Rabbits were sacrificed at 5 weeks and histopathological analysis and fluorescence microscopy performed. RESULTS All treated eyes developed haze and had epithelial erosions. No statistically significant differences in haze score were seen among individual treatment groups (Kruskal Wallis p > 0.05). The anti-transforming growth factor beta antibody group had less haze than all other groups at every week after the first. Comparing all transforming growth factor beta 1 treated eyes as one group to the antibody group, significantly less haze was seen at weeks 3 and 4 in the antibody treated group (p = 0.028 and 0.013, respectively). This study is limited by small group size and further studies are needed to confirm these results. CONCLUSION TGF-beta may be involved in stromal haze formation, and topical anti-TGF-beta 1 antibody may help reduce the development of stromal haze.
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Affiliation(s)
- J S Myers
- Wills Eye University Hospital, Philadelphia, Pennsylvania, USA
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Yang CB, Myers JS, Herndon LW, Allingham RR, Shields MB. Rate of progression in open-angle glaucoma estimated from cross-sectional prevalence of visual field damage. Am J Ophthalmol 1997; 123:426-8. [PMID: 9063267 DOI: 10.1016/s0002-9394(14)70154-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Myers JS, Warren T. Elastic net secures facial dressing comfortably. Oncol Nurs Forum 1996; 23:1484. [PMID: 8899765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- J S Myers
- Research Medical Center, Kansas City, MO, USA
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Myers JS, Schnall BM. Bilateral posterior lenticonus. Ophthalmic Surg 1995; 26:383-4. [PMID: 8532299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- J S Myers
- Pediatric Clinic, Wills Eye Hospital, Philadelphia, PA 19107, USA
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Myers JS, Kyle KS. Intermediate-term intravenous therapy: a pilot study. J Post Anesth Nurs 1993; 8:21-25. [PMID: 8478804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Midline catheters provide an effective alternative for intermediate-term intravenous therapy. During a pilot study, 27 midline catheters were inserted in patients who met specific criteria. The insertion success rate was 64%, and the infection rate was 7%. One mechanical phlebitis occurred, but it was resolved by the application of warm, moist heat. One chemical phlebitis occurred during antibiotic therapy. The average dwell time was 8.7 days, and the longest dwell time was 49 days. Patients reported the catheters to be very comfortable and did not experience limitations in mobility.
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Kyle KS, Myers JS. Peripherally inserted central catheters. Development of a hospital-based program. J Intraven Nurs 1990; 13:287-90. [PMID: 2401933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Peripherally inserted central catheter lines (PICCs) are the "new kids on the block" for intravenous therapy. This paper reports on the development of a protocol and training program for nurses at a 350-bed community hospital. The paper describes the development and implementation of this pilot program in 25 patients over a 1-year period.
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Myers JS, Davidson J, Hutt P, Chatham S. Standardized teaching plans for management of chemotherapy and radiation therapy side effects. Oncol Nurs Forum 1987; 14:95-9. [PMID: 3658784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Myers JS. Cancer pain: assessment of nurses' knowledge and attitudes. Oncol Nurs Forum 1985; 12:62-6. [PMID: 3847997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Myers JS, Gabriel O. Specific conversion of D-galactose into D-galacturonic acid residues in glycoproteins: a facile method for carbohydrate linkage-analysis. Carbohydr Res 1978; 67:223-34. [PMID: 709566 DOI: 10.1016/s0008-6215(00)83744-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The terminal D-galactopyranosyl residues of asialoglycopeptides isolated from human alpha1-acid glycoprotein were oxidized in nearly quantitative yield to the corresponding uronic acid residues by a two-step sequence employing D-galactose oxidase followed by treatment with Tollens reagent, Ag(NH3)+2. Mild acid hydrolysis of the oxidized glycopeptides led to the isolation of the corresponding aldobiuronic acid(s). Structural and colorimetric analysis revealed that only one aldobiuronic acid 2-amino-2-deoxy-4-O-(beta-D-galactopyranosyluronic acid)-D-glucose, was isolated from the oxidized glycopeptides of alpha1-acid glycoprotein. This method can readily distinguish between the (1 leads to 3), (1 leads to 4), and (1 leads to 6) isomers of the corresponding aldobiuronic acids.
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Myers JS, Jakoby WB. Glycerol as an agent eliciting small conformational changes in alcohol dehydrogenase. J Biol Chem 1975; 250:3785-9. [PMID: 165183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Yeast alcohol dehydrogenase is an example of a protein in which the K-m for substrate is substantially decreased by the presence of glycerol. The polyol has the effect at pH 8.0 or above of decreasing K-m and K-s for substrate and of altering both the protein's intrinsic fluorescence and ultraviolet absorption difference spectrum. The relationship between each of thse parameters and glycerol concentration displays a transition at a glycerol concentration of 20%. Circular dichroism values for the enzyme are not affected by glycerol over a large range of concentration and temperature. Treatment of the enzyme with glutaraldehyde results in the formation of cross-linked tetramers, the K-m of which are not altered by the presence of the solvent. The data are interpreted as reflecting a change in the conformation of the protein induced by glycerol.
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Myers JS, Hardman JK. Formaldehyde-induced cross-linkages in the subunit of the Escherichia coli tryptophan synthetase. J Biol Chem 1971; 246:3863-9. [PMID: 4934839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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