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Yin Y, Garcia MR, Novak AJ, Saunders AM, Ank RS, Nam AS, Fisher LW. Surf4 (Erv29p) binds amino-terminal tripeptide motifs of soluble cargo proteins with different affinities, enabling prioritization of their exit from the endoplasmic reticulum. PLoS Biol 2018; 16:e2005140. [PMID: 30086131 PMCID: PMC6097701 DOI: 10.1371/journal.pbio.2005140] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 08/17/2018] [Accepted: 07/17/2018] [Indexed: 01/16/2023] Open
Abstract
Some secreted proteins that assemble into large complexes, such as extracellular matrices or hormones and enzymes in storage granules, must be kept at subaggregation concentrations during intracellular trafficking. We show surfeit locus protein 4 (Surf4) is the cargo receptor that establishes different steady-state concentrations for a variety of soluble cargo proteins within the endoplasmic reticulum (ER) through interaction with the amino-terminal tripeptides exposed after removal of leader sequences. We call this motif the ER-Exit by Soluble Cargo using Amino-terminal Peptide-Encoding motif (ER-ESCAPE motif). Proteins that most readily aggregate in the ER lumen (e.g., dentin sialophosphoprotein [DSPP] and amelogenin, X-linked [AMELX]) have strong ER-ESCAPE motifs to inhibit aggregate formation, while less susceptible cargo exhibits weaker motifs. Specific changes in a single amino acid of the tripeptide result in aggregate formation and failure to efficiently traffic cargo out of the ER. A logical subset of 8,000 possible tripeptides starting a model soluble cargo protein (growth hormone) established a continuum of steady-state ER concentrations ranging from low (i.e., high affinity for receptor) to the highest concentrations associated with bulk flow-limited trafficking observed for nonbinding motifs. Human cells lacking Surf4 no longer preferentially trafficked cargo expressing strong ER-ESCAPE motifs. Reexpression of Surf4 or expression of yeast's ortholog, ER-derived vesicles protein 29 (Erv29p), rescued enhanced ER trafficking in Surf4-null cells. Hence our work describes a new way of preferentially exporting soluble cargo out of the ER that maintains proteins below the concentrations at which they form damaging aggregates.
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Affiliation(s)
- Ying Yin
- Matrix Biochemistry Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Mekka R. Garcia
- Matrix Biochemistry Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Alexander J. Novak
- Matrix Biochemistry Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Allison M. Saunders
- Matrix Biochemistry Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Raira S. Ank
- Matrix Biochemistry Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Anna S. Nam
- Matrix Biochemistry Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Larry W. Fisher
- Matrix Biochemistry Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
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Manso BA, Wenzl K, Asmann YW, Maurer MJ, Manske M, Yang ZZ, Slager SL, Nowakowski GS, Ansell SM, Witzig TE, Feldman AL, Rimsza L, Link B, Cerhan JR, Novak AJ. Whole-exome analysis reveals novel somatic genomic alterations associated with cell of origin in diffuse large B-cell lymphoma. Blood Cancer J 2017; 7:e553. [PMID: 28430174 PMCID: PMC5436076 DOI: 10.1038/bcj.2017.33] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- B A Manso
- Department of Immunology, Mayo Clinic, Rochester, MN, USA
| | - K Wenzl
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - Y W Asmann
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
| | - M J Maurer
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
| | - M Manske
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - Z-Z Yang
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - S L Slager
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
| | | | - S M Ansell
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - T E Witzig
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - A L Feldman
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - L Rimsza
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Scottsdale, AZ, USA
| | - B Link
- Department of Hematology, Oncology and Blood and Marrow Transplantation, University of Iowa, Iowa City, IA, USA
| | - J R Cerhan
- Division of Epidemiology, Mayo Clinic, Rochester, MN, USA
| | - A J Novak
- Department of Immunology, Mayo Clinic, Rochester, MN, USA.,Division of Hematology, Mayo Clinic, Rochester, MN, USA
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3
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Novak AJ, Asmann YW, Maurer MJ, Wang C, Slager SL, Hodge LS, Manske M, Price-Troska T, Yang ZZ, Zimmermann MT, Nowakowski GS, Ansell SM, Witzig TE, McPhail E, Ketterling R, Feldman AL, Dogan A, Link BK, Habermann TM, Cerhan JR. Whole-exome analysis reveals novel somatic genomic alterations associated with outcome in immunochemotherapy-treated diffuse large B-cell lymphoma. Blood Cancer J 2015; 5:e346. [PMID: 26314988 PMCID: PMC4558593 DOI: 10.1038/bcj.2015.69] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [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] [Received: 07/06/2015] [Accepted: 07/21/2015] [Indexed: 01/14/2023] Open
Abstract
Lack of remission or early relapse remains a major clinical issue in diffuse large B-cell lymphoma (DLBCL), with 30% of patients failing standard of care. Although clinical factors and molecular signatures can partially predict DLBCL outcome, additional information is needed to identify high-risk patients, particularly biologic factors that might ultimately be amenable to intervention. Using whole-exome sequencing data from 51 newly diagnosed and immunochemotherapy-treated DLBCL patients, we evaluated the association of somatic genomic alterations with patient outcome, defined as failure to achieve event-free survival at 24 months after diagnosis (EFS24). We identified 16 genes with mutations, 374 with copy number gains and 151 with copy number losses that were associated with failure to achieve EFS24 (P<0.05). Except for FOXO1 and CIITA, known driver mutations did not correlate with EFS24. Gene losses were localized to 6q21-6q24.2, and gains to 3q13.12-3q29, 11q23.1-11q23.3 and 19q13.12-19q13.43. Globally, the number of gains was highly associated with poor outcome (P=7.4 × 10−12) and when combined with FOXO1 mutations identified 77% of cases that failed to achieve EFS24. One gene (SLC22A16) at 6q21, a doxorubicin transporter, was lost in 54% of EFS24 failures and our findings suggest it functions as a doxorubicin transporter in DLBCL cells.
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Affiliation(s)
- A J Novak
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - Y W Asmann
- Department of Health Sciences Research, Mayo Clinic, Jacksonville, FL, USA
| | - M J Maurer
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
| | - C Wang
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
| | - S L Slager
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
| | - L S Hodge
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - M Manske
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | | | - Z-Z Yang
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - M T Zimmermann
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
| | | | - S M Ansell
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - T E Witzig
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - E McPhail
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - R Ketterling
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - A L Feldman
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - A Dogan
- Departments of Pathology and Laboratory Medicine, Hematopathology Service, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - B K Link
- Internal Medicine, University of Iowa, Iowa City, IA, USA
| | - T M Habermann
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - J R Cerhan
- Division of Epidemiology, Mayo Clinic, Rochester, MN, USA
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Asmann YW, Maurer MJ, Wang C, Sarangi V, Ansell SM, Feldman AL, Nowakowski GS, Manske M, Price-Troska T, Yang ZZ, Slager SL, Habermann TM, Cerhan JR, Novak AJ. Genetic diversity of newly diagnosed follicular lymphoma. Blood Cancer J 2014; 4:e256. [PMID: 25360902 PMCID: PMC4220653 DOI: 10.1038/bcj.2014.80] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Y W Asmann
- Department of Health Sciences Research, Mayo Clinic, Jacksonville, FL, USA
| | - M J Maurer
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
| | - C Wang
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
| | - V Sarangi
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
| | - S M Ansell
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - A L Feldman
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | | | - M Manske
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | | | - Z-Z Yang
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - S L Slager
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
| | - T M Habermann
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - J R Cerhan
- Division of Epidemiology, Mayo Clinic, Rochester, MN, USA
| | - A J Novak
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
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5
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Ansell SM, Hodge LS, Secreto FJ, Manske M, Braggio E, Price-Troska T, Ziesmer S, Li Y, Johnson SH, Hart SN, Kocher JPA, Vasmatzis G, Chanan-Kahn A, Gertz M, Fonseca R, Dogan A, Cerhan JR, Novak AJ. Activation of TAK1 by MYD88 L265P drives malignant B-cell Growth in non-Hodgkin lymphoma. Blood Cancer J 2014; 4:e183. [PMID: 24531446 PMCID: PMC3944662 DOI: 10.1038/bcj.2014.4] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [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] [Received: 11/11/2013] [Revised: 12/23/2013] [Accepted: 01/03/2014] [Indexed: 12/29/2022] Open
Abstract
Massively parallel sequencing analyses have revealed a common mutation within the MYD88 gene (MYD88L265P) occurring at high frequencies in many non-Hodgkin lymphomas (NHLs) including the rare lymphoplasmacytic lymphoma, Waldenström's macroglobulinemia (WM). Using whole-exome sequencing, Sanger sequencing and allele-specific PCR, we validate the initial studies and detect the MYD88L265P mutation in the tumor genome of 97% of WM patients analyzed (n=39). Due to the high frequency of MYD88 mutation in WM and other NHL, and its known effects on malignant B-cell survival, therapeutic targeting of MYD88 signaling pathways may be clinically useful. However, we are lacking a thorough characterization of the role of intermediary signaling proteins on the biology of MYD88L265P-expressing B cells. We report here that MYD88L265P signaling is constitutively active in both WM and diffuse large B-cell lymphoma cells leading to heightened MYD88L265P, IRAK and TRAF6 oligomerization and NF-κB activation. Furthermore, we have identified the signaling protein, TAK1, to be an essential mediator of MYD88L265P-driven signaling, cellular proliferation and cytokine secretion in malignant B cells. Our studies highlight the biological significance of MYD88L265P in NHL and reveal TAK1 inhibition to be a potential therapeutic strategy for the treatment of WM and other diseases characterized by MYD88L265P.
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Affiliation(s)
- S M Ansell
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - L S Hodge
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - F J Secreto
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - M Manske
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - E Braggio
- Division of Hematology, Mayo Clinic, Scottsdale, AZ, USA
| | | | - S Ziesmer
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - Y Li
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
| | - S H Johnson
- Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
| | - S N Hart
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
| | - J-P A Kocher
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
| | - G Vasmatzis
- Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
| | - A Chanan-Kahn
- Division of Hematology, Mayo Clinic, Jacksonville, FL, USA
| | - M Gertz
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - R Fonseca
- Division of Hematology, Mayo Clinic, Scottsdale, AZ, USA
| | - A Dogan
- Division of Anatomic Pathology and Hematopathology, Mayo Clinic, Rochester, MN, USA
| | - J R Cerhan
- Division of Epidemiology, Mayo Clinic, Rochester, MN, USA
| | - A J Novak
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
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6
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Hodge LS, Elsawa SF, Grote DM, Price-Troska TL, Asmann YW, Fonseca R, Gertz MA, Witzig TE, Novak AJ, Ansell SM. MicroRNA expression in tumor cells from Waldenstrom's macroglobulinemia reflects both their normal and malignant cell counterparts. Blood Cancer J 2011; 1:e24. [PMID: 22829168 PMCID: PMC3255267 DOI: 10.1038/bcj.2011.25] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 04/11/2011] [Accepted: 05/12/2011] [Indexed: 12/12/2022] Open
Abstract
MicroRNAs (miRNAs) are involved in the regulation of many cellular processes including hematopoiesis, with the aberrant expression of differentiation-stage specific miRNA associated with lymphomagenesis. miRNA profiling has been essential for understanding the underlying biology of many hematological malignancies; however the miRNA signature of the diverse tumor clone associated with Waldenstrom's macroglobulinemia (WM), consisting of B lymphocytes, plasmacytes and lymphoplasmacytic cells, has not been characterized. We have investigated the expression of over 13 000 known and candidate miRNAs in both CD19(+) and CD138(+) WM tumor cells, as well as in their malignant and non-malignant counterparts. Although neither CD19(+) nor CD138(+) WM cells were defined by a distinct miRNA profile, the combination of all WM cells revealed a unique miRNA transcriptome characterized by the dysregulation of many miRNAs previously identified as crucial for normal B-cell lineage differentiation. Specifically, miRNA-9(*)/152/182 were underexpressed in WM, whereas the expression of miRNA-21/125b/181a/193b/223/363 were notably increased (analysis of variance; P<0.0001). Future studies focusing on the effects of these dysregulated miRNAs will provide further insight into the mechanisms responsible for the pathogenesis of WM.
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Affiliation(s)
- L S Hodge
- Division of Hematology and Internal Medicine, Mayo Clinic, Rochester, MN, USA
| | - S F Elsawa
- Division of Hematology and Internal Medicine, Mayo Clinic, Rochester, MN, USA
| | - D M Grote
- Division of Hematology and Internal Medicine, Mayo Clinic, Rochester, MN, USA
| | - T L Price-Troska
- Division of Hematology and Internal Medicine, Mayo Clinic, Rochester, MN, USA
| | - Y W Asmann
- Division of Biomedical Informatics, Mayo Clinic, Rochester, MN, USA
| | - R Fonseca
- Comprehensive Cancer Center, Mayo Clinic, Scottsdale, AZ, USA
| | - M A Gertz
- Division of Hematology and Internal Medicine, Mayo Clinic, Rochester, MN, USA
| | - T E Witzig
- Division of Hematology and Internal Medicine, Mayo Clinic, Rochester, MN, USA
| | - A J Novak
- Division of Hematology and Internal Medicine, Mayo Clinic, Rochester, MN, USA
| | - S M Ansell
- Division of Hematology and Internal Medicine, Mayo Clinic, Rochester, MN, USA
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7
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Novak AJ, Grote DM, Ziesmer SC, Rajkumar V, Doyle SE, Ansell SM. A role for IFN-lambda1 in multiple myeloma B cell growth. Leukemia 2008; 22:2240-6. [PMID: 18830264 PMCID: PMC2771776 DOI: 10.1038/leu.2008.263] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2008] [Revised: 06/26/2008] [Accepted: 08/14/2008] [Indexed: 11/08/2022]
Abstract
Multiple myeloma (MM) is a progressive disease that results from dysregulated proliferation of plasma cells. Although, causative factors such as genetic events and altered expression of anti-apoptotic factors have been described in a number of patients, the mechanistic details that drive myeloma development and continued growth of malignant cells remain largely undefined. Numerous growth factors, including interleukin (IL)-6, Insulin-like growth factor-1 and IL-10 have been shown to promote growth of MM cells suggesting a significant role for cytokines in this disease. Interferon (IFN)-lambda1 is a new member of the Class II cytokine family that, similar to IFN-alpha, has been shown to mediate viral immunity. In light of data supporting a role for cytokines in myeloma, we investigated the significance of IFN-lambda1 on myeloma cell biology. Our studies show for the first time that myeloma cells bind to soluble IFN-lambda1, and that IFN-lambda1 induces myeloma cell growth and protects against dexamethasone-induced cell death. Our data also show that IFN-lambda1 induces phosphorylation of STAT1, STAT3 and Erk. Taken together, our results suggest that IFN-lambda1 may regulate myeloma cell biology and could prove to be therapeutically important.
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Affiliation(s)
- AJ Novak
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - DM Grote
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - SC Ziesmer
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - V Rajkumar
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - SE Doyle
- Department of Hematology and Oncology, ZymoGenetics Inc., Seattle, WA, USA
| | - SM Ansell
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
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8
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Ansell SM, Arendt BK, Grote DM, Jelinek DF, Novak AJ, Wellik LE, Remstein ED, Bennett CF, Fielding A. Inhibition of survivin expression suppresses the growth of aggressive non-Hodgkin's lymphoma. Leukemia 2004; 18:616-23. [PMID: 14749704 DOI: 10.1038/sj.leu.2403281] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Survivin is a member of the inhibitor of apoptosis protein (IAP) family and functions both as an apoptosis inhibitor and a regulator of cell division. Survivin overexpression is common in many human tumors and correlates with survival in large cell non-Hodgkin's lymphoma. To evaluate this molecule as a potential therapeutic target in large-cell lymphoma, we evaluated the effect of survivin inhibition both in vitro and in vivo. Using an antisense oligonucleotide (ASO) approach, cell growth was significantly inhibited in the DoHH2, RL and HT lymphoma cell lines. In a lymphoma xenograft model, the development of tumors as well as the growth of established tumors was inhibited in the survivin ASO-treated mice compared to controls. To assess the efficacy of the survivin ASO in combination with other biological agents, we combined the survivin ASO with an anti-CD20 monoclonal antibody, rituximab. The effect of survivin ASO and rituximab in combination was additive in vitro. In vivo, however, suppression of tumor growth with the combination was not significantly superior to controls. We conclude that inhibition of survivin expression is an attractive therapeutic strategy in aggressive non-Hodgkin's lymphomas, and that combining survivin ASO with rituximab may enhance the efficacy of this approach.
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Affiliation(s)
- S M Ansell
- Division of Hematology, Mayo Clinic, Rochester, MN, USA.
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9
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Feichtinger G, Novak AJ. How stock dependent flow rates may imply chaos in educational planning. Math Popul Stud 1994; 5:75-121. [PMID: 12288880 DOI: 10.1080/08898489409525388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
"The aim of the present paper is to illustrate how extremely complex patterns may be generated in a simple model of educational planning. In particular, we will show that certain dependencies of the flow rates on the teacher/student ratio imply nonlinearities which are substantial enough to generate erratic behaviour of the time paths. The main message is that chaos in educational planning may result from assumptions which are indeed qualitatively realistic but which are quantitatively exaggerated." (SUMMARY IN FRE)
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10
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Novak AJ. Driving and epilepsy: the effects of medication. JAMA 1991; 265:2961-2. [PMID: 2033765] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Paul BD, Mell LD, Mitchell JM, Irving J, Novak AJ. Simultaneous identification and quantitation of codeine and morphine in urine by capillary gas chromatography and mass spectroscopy. J Anal Toxicol 1985; 9:222-6. [PMID: 4057960 DOI: 10.1093/jat/9.5.222] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
An analytical procedure for simultaneous determination of codeine and morphine in urine is described. The detection of codeine and morphine is based on liquid-liquid extraction and derivatization to the acetylated compounds. The acetylated codeine and morphine are separated by capillary gas chromatography and identified mass spectrometrically by selected ion monitoring (SIM). Quantitative determination was carried out by SIM using nalorphine as internal standard. Excellent linearity was obtained over a concentration range of 25 to 800 ng/mL. The overall recovery for codeine and morphine in the extraction was found to be 58% and 40%, respectively. The on-column sensitivity for both compounds was 2 ng at a peak-to-noise ratio of 5:1. The derivatives, acetylcodeine, diacetylmorphine, and diacetylnalorphine were stable at room temperature for 72 hr.
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13
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Novak AJ, Berry DF, Walters BS, Passino DR. New continuous-flow bioassay technique using small crustaceans. Bull Environ Contam Toxicol 1982; 29:253-260. [PMID: 7126914 DOI: 10.1007/bf01706225] [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] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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14
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Novak AJ. Quantitative evaluation of oral topical analgesia. Oral Surg Oral Med Oral Pathol 1972; 34:34-40. [PMID: 4556451 DOI: 10.1016/0030-4220(72)90270-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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15
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Novak AJ. Prescription problems ... and solutions. Dent Manage 1971; 11:38 passim. [PMID: 5277274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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