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Kusznir EA, Hau JC, Portmann M, Reinhart AG, Falivene F, Bastien J, Worm J, Ross A, Lauer M, Ringler P, Sladojevich F, Huber S, Bleicher K, Keller M. Propensities of Fatty Acid-Modified ASOs: Self-Assembly vs Albumin Binding. Bioconjug Chem 2023; 34:866-879. [PMID: 37145959 DOI: 10.1021/acs.bioconjchem.3c00085] [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: 05/07/2023]
Abstract
We conducted a biophysical study to investigate the self-assembling and albumin-binding propensities of a series of fatty acid-modified locked nucleic acid (LNA) antisense oligonucleotide (ASO) gapmers specific to the MALAT1 gene. To this end, a series of biophysical techniques were applied using label-free ASOs that were covalently modified with saturated fatty acids (FAs) of varying length, branching, and 5'/3' attachment. Using analytical ultracentrifugation (AUC), we demonstrate that ASOs conjugated with fatty acids longer than C16 exhibit an increasing tendency to form self-assembled vesicular structures. The C16 to C24 conjugates interacted via the fatty acid chains with mouse and human serum albumin (MSA/HSA) to form stable adducts with near-linear correlation between FA-ASO hydrophobicity and binding strength to mouse albumin. This was not observed for the longer fatty acid chain ASO conjugates (>C24) under the experimental conditions applied. The longer FA-ASO however adopted self-assembled structures with increasing intrinsic stabilities proportional to the fatty acid chain length. For instance, FA chain lengths smaller than C24 readily formed self-assembled structures containing 2 (C16), 6 (C22, bis-C12), and 12 (C24) monomers, as measured by analytical ultracentrifugation (AUC). Incubation with albumin disrupted these supramolecular architectures to form FA-ASO/albumin complexes mostly with 2:1 stoichiometry and binding affinities in the low micromolar range, as determined by isothermal titration calorimetry (ITC) and analytical ultracentrifugation (AUC). Binding of FA-ASOs underwent a biphasic pattern for medium-length FA chain lengths (>C16) with an initial endothermic phase of particulate disruption, followed by an exothermic binding event to the albumin. Conversely, ASO modified with di-palmitic acid (C32) formed a strong, hexameric complex. This structure was not disrupted when incubated with albumin under conditions above the critical nanoparticle concentration (CNC; <0.4 μM). It is noteworthy that the interaction of parent, fatty acid-free malat1 ASO to albumin was below detectability by ITC (KD ≫150 μM). This work demonstrates that the nature of mono- vs multimeric structures of hydrophobically modified ASOs is governed by the hydrophobic effect. Consequently, supramolecular assembly to form particulate structures is a direct consequence of the fatty acid chain length. This provides opportunities to exploit the concept of hydrophobic modification to influence pharmacokinetics (PK) and biodistribution for ASOs in two ways: (1) binding of the FA-ASO to albumin as a carrier vehicle and (2) self-assembly resulting in albumin-inert, supramolecular architectures. Both concepts create opportunities to influence biodistribution, receptor interaction, uptake mechanism, and pharmacokinetics/pharmacodynamics (PK/PD) properties in vivo, potentially enabling access to extrahepatic tissues in sufficient concentration to treat disease.
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Affiliation(s)
- Eric-André Kusznir
- Roche Pharma Research and Early Development, Therapeutic Modalities, Lead Discovery, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Jean-Christophe Hau
- Roche Pharma Research and Early Development, Therapeutic Modalities, Lead Discovery, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Michaela Portmann
- Roche Pharma Research and Early Development, Therapeutic Modalities, pCMC, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Anne-Gaëlle Reinhart
- Roche Pharma Research and Early Development, Therapeutic Modalities, pCMC, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Fabio Falivene
- Roche Pharma Research and Early Development, Therapeutic Modalities, pCMC, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Jessica Bastien
- Roche Pharma Research and Early Development, Therapeutic Modalities, RMR, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Jesper Worm
- Roche Pharma Research and Early Development, Therapeutic Modalities, RMR, Roche Innovation Center Copenhagen, F. Hoffmann-La Roche Ltd., Fremtidsvej 3, 2970 Hoersholm, Denmark
| | - Alfred Ross
- Roche Pharma Research and Early Development, Therapeutic Modalities, pCMC, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Matthias Lauer
- Roche Pharma Research and Early Development, Therapeutic Modalities, Lead Discovery, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Philippe Ringler
- Biozentrum, University of Basel, Spitalstrasse 41, CH - 4056 Basel, Switzerland
| | - Filippo Sladojevich
- Roche Pharma Research and Early Development, Therapeutic Modalities, pCMC, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Sylwia Huber
- Roche Pharma Research and Early Development, Therapeutic Modalities, Lead Discovery, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Konrad Bleicher
- Roche Pharma Research and Early Development, Therapeutic Modalities, RMR, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Michael Keller
- Roche Pharma Research and Early Development, Therapeutic Modalities, pCMC, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
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2
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Campbell A, Morris G, Sanfeliu A, Augusto J, Langa E, Kesavan JC, Nguyen NT, Conroy RM, Worm J, Kielpinski L, Jensen MA, Miller MT, Kremer T, Reschke CR, Henshall DC. AntimiR targeting of microRNA-134 reduces seizures in a mouse model of Angelman syndrome. Mol Ther Nucleic Acids 2022; 28:514-529. [PMID: 35592499 PMCID: PMC9092865 DOI: 10.1016/j.omtn.2022.04.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 04/15/2022] [Indexed: 10/26/2022]
Abstract
Angelman syndrome (AS) is a severe neurodevelopmental disorder featuring ataxia, cognitive impairment, and drug-resistant epilepsy. AS is caused by mutations or deletion of the maternal copy of the paternally imprinted UBE3A gene, with current precision therapy approaches focusing on re-expression of UBE3A. Certain phenotypes, however, are difficult to rescue beyond early development. Notably, a cluster of microRNA binding sites was reported in the untranslated Ube3a1 transcript, including for miR-134, suggesting that AS may be associated with microRNA dysregulation. Here, we report levels of miR-134 and key targets are normal in the hippocampus of mice carrying a maternal deletion of Ube3a (Ube3a m-/p+ ). Nevertheless, intracerebroventricular injection of an antimiR oligonucleotide inhibitor of miR-134 (Ant-134) reduced audiogenic seizure severity over multiple trials in 21- and 42-day-old AS mice. Interestingly, Ant-134 also improved distance traveled and center crossings of AS mice in the open-field test. Finally, we show that silencing miR-134 can upregulate targets of miR-134 in neurons differentiated from Angelman patient-derived induced pluripotent stem cells. These findings indicate that silencing miR-134 and possibly other microRNAs could be useful to treat clinically relevant phenotypes with a later developmental window in AS.
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Affiliation(s)
- Aoife Campbell
- Department of Physiology and Medical Physics, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland.,FutureNeuro, The SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Gareth Morris
- Department of Physiology and Medical Physics, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland.,FutureNeuro, The SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Albert Sanfeliu
- Department of Physiology and Medical Physics, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland.,FutureNeuro, The SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Joana Augusto
- Department of Physiology and Medical Physics, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland.,FutureNeuro, The SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Elena Langa
- Department of Physiology and Medical Physics, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland.,FutureNeuro, The SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Jaideep C Kesavan
- Department of Physiology and Medical Physics, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland.,FutureNeuro, The SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Ngoc T Nguyen
- Department of Physiology and Medical Physics, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland.,FutureNeuro, The SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Ronan M Conroy
- Department of Public Health and Epidemiology, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Jesper Worm
- Therapeutic Modalities, Roche Innovation Center Copenhagen A/S, F. Hoffmann-La Roche Ltd, DK-2970 Hørsholm, Denmark
| | - Lukasz Kielpinski
- Therapeutic Modalities, Roche Innovation Center Copenhagen A/S, F. Hoffmann-La Roche Ltd, DK-2970 Hørsholm, Denmark
| | - Mads Aaboe Jensen
- Therapeutic Modalities, Roche Innovation Center Copenhagen A/S, F. Hoffmann-La Roche Ltd, DK-2970 Hørsholm, Denmark
| | - Meghan T Miller
- Neuroscience and Rare Diseases Discovery and Translational Area, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland
| | - Thomas Kremer
- Neuroscience and Rare Diseases Discovery and Translational Area, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland
| | - Cristina R Reschke
- Department of Physiology and Medical Physics, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland.,FutureNeuro, The SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland.,School of Pharmacy and Biomedical Sciences, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - David C Henshall
- Department of Physiology and Medical Physics, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland.,FutureNeuro, The SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
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3
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Mughal RS, Bridge K, Buza I, Slaaby R, Worm J, Klitgaard-Povlsen G, Hvid H, Schiødt M, Cubbon R, Yuldasheva N, Skromna A, Makava N, Skytte-Olsen G, Kearney MT. Effects of obesity on insulin: insulin-like growth factor 1 hybrid receptor expression and Akt phosphorylation in conduit and resistance arteries. Diab Vasc Dis Res 2019; 16:160-170. [PMID: 30295509 PMCID: PMC6484231 DOI: 10.1177/1479164118802550] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Insulin and insulin-like growth factor-1 stimulate specific responses in arteries, which may be disrupted by diet-induced obesity. We examined (1) temporal effects of high-fat diet compared to low-fat diet in mice on insulin receptor, insulin-like growth factor-1 receptor, insulin receptor/insulin-like growth factor-1 receptor hybrid receptor expression and insulin/insulin-like growth factor-1-mediated Akt phosphorylation in aorta; and (2) effects of high-fat diet on insulin and insulin-like growth factor-1-mediated Akt phosphorylation and vascular tone in resistance arteries. Medium-term high-fat diet (5 weeks) decreased insulin-like growth factor-1 receptor expression and increased hybrid expression (~30%) only. After long-term (16 weeks) high-fat diet, insulin receptor expression was reduced by ~30%, insulin-like growth factor-1 receptor expression decreased a further ~40% and hybrid expression increased a further ~60%. Independent correlates of hybrid receptor expression were high-fat diet, duration of high-fat diet and plasma insulin-like growth factor-1 (all p < 0.05). In aorta, insulin was a more potent activator of Akt than insulin-like growth factor-1, whereas in resistance arteries, insulin-like growth factor-1 was more potent than insulin. High-fat diet blunted insulin-mediated vasorelaxation ( p < 0.01) but had no effect on insulin-like growth factor-1-mediated vasorelaxation in resistance arteries. Our findings support the possibility that hybrid receptor level is influenced by nutritional and metabolic cues. Moreover, vessel-dependent effects of insulin and insulin-like growth factor-1 on vascular tone and Akt activation may have implications in treating obesity-related vascular disease.
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MESH Headings
- Animals
- Antigens, CD/metabolism
- Aorta/drug effects
- Aorta/enzymology
- Cells, Cultured
- Diet, Fat-Restricted
- Diet, High-Fat
- Disease Models, Animal
- Enzyme Activation
- Human Umbilical Vein Endothelial Cells/drug effects
- Human Umbilical Vein Endothelial Cells/enzymology
- Humans
- Insulin/pharmacology
- Insulin-Like Growth Factor I/pharmacology
- Male
- Mesenteric Arteries/drug effects
- Mesenteric Arteries/enzymology
- Mesenteric Arteries/physiopathology
- Mice, Inbred C57BL
- Obesity/blood
- Obesity/enzymology
- Obesity/physiopathology
- Phosphorylation
- Proto-Oncogene Proteins c-akt/metabolism
- Receptor, IGF Type 1/genetics
- Receptor, IGF Type 1/metabolism
- Receptor, Insulin/metabolism
- Receptors, Somatomedin/metabolism
- Signal Transduction/drug effects
- Vascular Resistance/drug effects
- Vasodilation/drug effects
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Affiliation(s)
- Romana S Mughal
- Division of Cardiovascular and Diabetes Research, Leeds Institute of Cardiovascular and Metabolic Medicine (LICAMM), School of Medicine, University of Leeds, Leeds, UK
| | - Katherine Bridge
- Division of Cardiovascular and Diabetes Research, Leeds Institute of Cardiovascular and Metabolic Medicine (LICAMM), School of Medicine, University of Leeds, Leeds, UK
| | - Irma Buza
- Global Research, Novo Nordisk A/S, Malov, Denmark
| | - Rita Slaaby
- Global Research, Novo Nordisk A/S, Malov, Denmark
| | - Jesper Worm
- Global Research, Novo Nordisk A/S, Malov, Denmark
| | | | - Henning Hvid
- Global Research, Novo Nordisk A/S, Malov, Denmark
| | | | - Richard Cubbon
- Division of Cardiovascular and Diabetes Research, Leeds Institute of Cardiovascular and Metabolic Medicine (LICAMM), School of Medicine, University of Leeds, Leeds, UK
| | - Nadira Yuldasheva
- Division of Cardiovascular and Diabetes Research, Leeds Institute of Cardiovascular and Metabolic Medicine (LICAMM), School of Medicine, University of Leeds, Leeds, UK
| | - Anna Skromna
- Division of Cardiovascular and Diabetes Research, Leeds Institute of Cardiovascular and Metabolic Medicine (LICAMM), School of Medicine, University of Leeds, Leeds, UK
| | - Natallia Makava
- Division of Cardiovascular and Diabetes Research, Leeds Institute of Cardiovascular and Metabolic Medicine (LICAMM), School of Medicine, University of Leeds, Leeds, UK
| | | | - Mark T Kearney
- Division of Cardiovascular and Diabetes Research, Leeds Institute of Cardiovascular and Metabolic Medicine (LICAMM), School of Medicine, University of Leeds, Leeds, UK
- Mark T Kearney, Division of Cardiovascular and Diabetes Research, Leeds Institute of Cardiovascular and Metabolic Medicine (LICAMM), School of Medicine, University of Leeds, Leeds LS2 9JT, UK.
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4
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Østergaard MV, Pinto V, Stevenson K, Worm J, Fink LN, Coward RJM. DBA2J db/db mice are susceptible to early albuminuria and glomerulosclerosis that correlate with systemic insulin resistance. Am J Physiol Renal Physiol 2016; 312:F312-F321. [PMID: 27852608 DOI: 10.1152/ajprenal.00451.2016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [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: 08/10/2016] [Revised: 10/26/2016] [Accepted: 11/09/2016] [Indexed: 12/12/2022] Open
Abstract
Diabetic nephropathy (DN) is the leading cause of kidney failure in the world. To understand important mechanisms underlying this condition, and to develop new therapies, good animal models are required. In mouse models of type 1 diabetes, the DBA/2J strain has been shown to be more susceptible to develop kidney disease than other common strains. We hypothesized this would also be the case in type 2 diabetes. We studied db/db and wild-type (wt) DBA/2J mice and compared these with the db/db BLKS/J mouse, which is currently the most widely used type 2 DN model. Mice were analyzed from age 6 to 12 wk for systemic insulin resistance, albuminuria, and glomerular histopathological and ultrastructural changes. Body weight and nonfasted blood glucose were increased by 8 wk in both genders, while systemic insulin resistance commenced by 6 wk in female and 8 wk in male db/db DBA/2J mice. The urinary albumin-to-creatinine ratio (ACR) was closely linked to systemic insulin resistance in both sexes and was increased ~50-fold by 12 wk of age in the db/db DBA/2J cohort. Glomerulosclerosis, foot process effacement, and glomerular basement membrane thickening were observed at 12 wk of age in db/db DBA/2J mice. Compared with db/db BLKS/J mice, db/db DBA/2J mice had significantly increased levels of urinary ACR, but similar glomerular histopathological and ultrastructural changes. The db/db DBA/2J mouse is a robust model of early-stage albuminuric DN, and its levels of albuminuria correlate closely with systemic insulin resistance. This mouse model will be helpful in defining early mechanisms of DN and ultimately the development of novel therapies.
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Affiliation(s)
- Mette V Østergaard
- Global Research, Novo Nordisk, Måløv, Denmark.,Bristol Renal, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom; and
| | - Vanda Pinto
- Bristol Renal, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom; and
| | - Kirsty Stevenson
- Department of Biochemistry, Bristol Royal Infirmary, Bristol, United Kingdom
| | - Jesper Worm
- Global Research, Novo Nordisk, Måløv, Denmark
| | | | - Richard J M Coward
- Bristol Renal, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom; and
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5
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Worm J. Insulin and insulin-like growth factor-1 inhibit monocyte adhesion to endothelial cells. Atherosclerosis 2015. [DOI: 10.1016/j.atherosclerosis.2015.04.263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Baricevic I, Jones DR, Roberts DL, Lutzen A, Lundby A, Worm J, Hansen BF, Renehan AG. A framework for the in vitro evaluation of cancer-relevant molecular characteristics and mitogenic potency of insulin analogues. Carcinogenesis 2015; 36:1040-50. [PMID: 26026165 PMCID: PMC4552242 DOI: 10.1093/carcin/bgv071] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [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: 11/19/2014] [Accepted: 04/16/2015] [Indexed: 12/28/2022] Open
Abstract
Clinically prescribed insulin analogues are putatively linked with increased cancer risk. We developed a framework for the mandated regulatory in vitro evaluation of cancer-relevant bioassays for comparisons of insulin analogues, and showed that the cell-specific IGF-IR/IR ratio is crucial for interpretation. Epidemiological and laboratory studies raise the possibility of a link between clinically prescribed insulin analogues and increased cancer risk. Accordingly, there is a regulatory mandate for cancer-related pre-clinical safety evaluation during insulin analogue development, but currently, there is no standardized framework for such in vitro evaluation. We tested human insulin; the super-mitogenic insulin, X10 and insulin-like growth factor I, in four cancer cell lines with a range of insulin-like growth factor-I receptor (IGF-IR)/IR (insulin receptor) ratios (HCT 116, HT-29, COLO 205 and MCF7) and related these to IGF-IR and IR expression in 17 human adenocarcinomas. All cell types were IR-A isoform dominant. We determined IGF-IR/IR signalling pathway endpoints in dose- and time-varying experiments, and performed mitogenic dose–response equivalent assays to derive EC50 values, and correlated these with IGF-IR/IR ratios. We superimposed relative EC50 values onto data from the literature in a meta-analysis. The IGF-IR/IR ratios varied from <1 to 12 in the selected cell lines; similar pattern ranges were observed in human adenocarcinomas. The three ligands demonstrated differential IR/IGF-IR and Akt phosphorylation, which correlated with cell-specific IGF-IR/IR ratios. Mitogenic profiles of X10 mimicked those for insulin-like growth factor I (IGF-I) and correlated with IGF-IR/IR ratios. The meta-analysis, adding data from five additional studies, supported the hypothesis that ligand mitogenic potency, relative to human insulin, increases with increasing cell-specific IGF-IR/IR ratio. This study established a framework for the in vitro evaluation of cancer-relevant bioassays for comparisons of insulin analogues, and specifically consolidated earlier studies that determination of the cell-specific IGF-IR/IR ratio is crucial for the interpretation of ranking relative biological activities.
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Affiliation(s)
- Ivona Baricevic
- Faculty Institute of Cancer Sciences, Manchester Academic Health Science Centre, The Christie NHS Foundation Trust, University of Manchester, Wilmslow Road, Manchester M20 4BX, UK, Inositide Laboratory, Cancer Research UK Manchester Institute, Paterson Building, Manchester M20 4BX, UK and Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark
| | - David R Jones
- Inositide Laboratory, Cancer Research UK Manchester Institute, Paterson Building, Manchester M20 4BX, UK and
| | - Darren L Roberts
- Faculty Institute of Cancer Sciences, Manchester Academic Health Science Centre, The Christie NHS Foundation Trust, University of Manchester, Wilmslow Road, Manchester M20 4BX, UK, Inositide Laboratory, Cancer Research UK Manchester Institute, Paterson Building, Manchester M20 4BX, UK and Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark
| | - Anne Lutzen
- Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark
| | - Anders Lundby
- Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark
| | - Jesper Worm
- Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark
| | - Bo F Hansen
- Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark
| | - Andrew G Renehan
- Faculty Institute of Cancer Sciences, Manchester Academic Health Science Centre, The Christie NHS Foundation Trust, University of Manchester, Wilmslow Road, Manchester M20 4BX, UK, Inositide Laboratory, Cancer Research UK Manchester Institute, Paterson Building, Manchester M20 4BX, UK and Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark
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7
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Lundby A, Bolvig P, Hegelund AC, Hansen BF, Worm J, Lützen A, Billestrup N, Bonnesen C, Oleksiewicz MB. Surface-expressed insulin receptors as well as IGF-I receptors both contribute to the mitogenic effects of human insulin and its analogues. J Appl Toxicol 2014; 35:842-50. [DOI: 10.1002/jat.3082] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 09/13/2014] [Accepted: 09/15/2014] [Indexed: 11/09/2022]
Affiliation(s)
- Anders Lundby
- Department of Biomedical Sciences; University of Copenhagen; Blegdamsvej 3 2200 Copenhagen N Denmark
| | - Pernille Bolvig
- Diabetes Research Unit, Novo Nordisk A/S; Novo Nordisk Park 2760 Maaloev Denmark
| | | | - Bo F. Hansen
- Diabetes Research Unit, Novo Nordisk A/S; Novo Nordisk Park 2760 Maaloev Denmark
| | - Jesper Worm
- Diabetes Research Unit, Novo Nordisk A/S; Novo Nordisk Park 2760 Maaloev Denmark
| | - Anne Lützen
- Diabetes Research Unit, Novo Nordisk A/S; Novo Nordisk Park 2760 Maaloev Denmark
| | - Nils Billestrup
- Department of Biomedical Sciences; University of Copenhagen; Blegdamsvej 3 2200 Copenhagen N Denmark
| | - Christine Bonnesen
- Diabetes Research Unit, Novo Nordisk A/S; Novo Nordisk Park 2760 Maaloev Denmark
| | - Martin B. Oleksiewicz
- Centre for Biosecurity and Biopreparedness; Statens Serum Institute; Artillerivej 5 2300 Copenhagen S Denmark
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8
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Thomsen ARB, Worm J, Jacobsen SE, Stahlhut M, Latta M, Bräuner-Osborne H. Strontium is a biased agonist of the calcium-sensing receptor in rat medullary thyroid carcinoma 6-23 cells. J Pharmacol Exp Ther 2012; 343:638-49. [PMID: 22942242 PMCID: PMC11047797 DOI: 10.1124/jpet.112.197210] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [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: 06/07/2012] [Accepted: 08/30/2012] [Indexed: 09/23/2023] Open
Abstract
The calcium-sensing receptor (CaSR)-specific allosteric modulator cinacalcet has revolutionized the treatment of secondary hyperparathyroidism in patients with chronic kidney disease. However, its application is limited to patients with end-stage renal disease because of hypocalcemic side effects presumably caused by CaSR-mediated calcitonin secretion from thyroid parafollicular C-cells. These hypocalcemic side effects might be dampened by compounds that bias the signaling of CaSR, causing similar therapeutic effects as cinacalcet without stimulating calcitonin secretion. Because biased signaling of CaSR is poorly understood, the objective of the present study was to investigate biased signaling of CaSR by using rat medullary thyroid carcinoma 6-23 cells as a model of thyroid parafollicular C-cells. By doing concentration-response experiments we focused on the ability of two well known CaSR agonists, calcium and strontium, to activate six different signaling entities: G(q/11) signaling, G(i/o) signaling, G(s) signaling, extracellular signal-regulated kinases 1 and 2 (ERK1/2) signaling, intracellular calcium ([Ca(2+)](i)) mobilization, and calcitonin secretion. The experiments showed that strontium biases CaSR signaling toward ERK1/2 signaling and possibly another pathway independent of G(q/11) signaling and [Ca(2+)](i) mobilization. It is noteworthy that the potency of strontium-stimulated calcitonin secretion was elevated compared with calcium. Combining these results with experiments investigating signaling pathway components involved in calcitonin secretion, we found that the enhanced potency of strontium-mediated calcitonin secretion was caused by a different signaling pattern than that produced by calcium. Together, our results suggest that calcitonin secretion can be affected by CaSR-stimulated signaling bias, which may be used to develop novel drugs for the treatment of secondary hyperparathyroidism.
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Affiliation(s)
- Alex Rojas Bie Thomsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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9
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Dürig J, Dührsen U, Klein-Hitpass L, Worm J, Hansen JBR, Ørum H, Wissenbach M. The novel antisense Bcl-2 inhibitor SPC2996 causes rapid leukemic cell clearance and immune activation in chronic lymphocytic leukemia. Leukemia 2011; 25:638-47. [PMID: 21358717 DOI: 10.1038/leu.2010.322] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [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]
Abstract
SPC2996 is a novel locked nucleic acid phosphorothioate antisense molecule targeting the mRNA of the Bcl-2 oncoprotein. We investigated the mechanism of action of SPC2996 and the basis for its clinically observed immunostimulatory effects in chronic lymphocytic leukemia (CLL). Patients with relapsed CLL were treated with a maximum of six doses of SPC2996 (0.2-6 mg/kg) in a multicenter phase I trial. Microarray-based transcriptional profiling of circulating CLL cells was carried out before and after the first infusion of SPC2996 in 18 patients. Statistically significant transcriptomic changes were observed at doses 4 mg/kg and occurred as early as 24 h after the first infusion of the oligonucleotide. SPC2996 induced the upregulation of 466 genes including a large number of immune response and apoptotic regulator molecules, which were enriched for Toll-like receptor response genes. Serum measurements confirmed the release of pro-inflammatory cytokines including chemokine (C-C motif) ligand 3 (macrophage inflammatory protein 1α) and tumor necrosis factor-α, thereby validating the in vivo transcriptomic data at the protein level. SPC2996 caused a 50% reduction of circulating lymphocytes in five of 18 (28%) patients, which was found to be independent of its immunostimulatory and anti-Bcl-2 effects.
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Affiliation(s)
- J Dürig
- Department of Hematology, University Hospital, University of Duisburg-Essen, Essen, Germany.
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10
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Stein CA, Hansen JB, Lai J, Wu S, Voskresenskiy A, Høg A, Worm J, Hedtjärn M, Souleimanian N, Miller P, Soifer HS, Castanotto D, Benimetskaya L, Ørum H, Koch T. Efficient gene silencing by delivery of locked nucleic acid antisense oligonucleotides, unassisted by transfection reagents. Nucleic Acids Res 2009; 38:e3. [PMID: 19854938 PMCID: PMC2800216 DOI: 10.1093/nar/gkp841] [Citation(s) in RCA: 290] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
For the past 15–20 years, the intracellular delivery and silencing activity of oligodeoxynucleotides have been essentially completely dependent on the use of a delivery technology (e.g. lipofection). We have developed a method (called ‘gymnosis’) that does not require the use of any transfection reagent or any additives to serum whatsoever, but rather takes advantage of the normal growth properties of cells in tissue culture in order to promote productive oligonucleotide uptake. This robust method permits the sequence-specific silencing of multiple targets in a large number of cell types in tissue culture, both at the protein and mRNA level, at concentrations in the low micromolar range. Optimum results were obtained with locked nucleic acid (LNA) phosphorothioate gap-mers. By appropriate manipulation of oligonucleotide dosing, this silencing can be continuously maintained with little or no toxicity for >240 days. High levels of oligonucleotide in the cell nucleus are not a requirement for gene silencing, contrary to long accepted dogma. In addition, gymnotic delivery can efficiently deliver oligonucleotides to suspension cells that are known to be very difficult to transfect. Finally, the pattern of gene silencing of in vitro gymnotically delivered oligonucleotides correlates particularly well with in vivo silencing. The establishment of this link is of particular significance to those in the academic research and drug discovery and development communities.
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Affiliation(s)
- C A Stein
- Albert Einstein-Montefiore Cancer Center, Montefiore Medical Center, Bronx, NY 10467, USA.
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11
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Worm J, Stenvang J, Petri A, Frederiksen KS, Obad S, Elmén J, Hedtjärn M, Straarup EM, Hansen JB, Kauppinen S. Silencing of microRNA-155 in mice during acute inflammatory response leads to derepression of c/ebp Beta and down-regulation of G-CSF. Nucleic Acids Res 2009; 37:5784-92. [PMID: 19596814 PMCID: PMC2761263 DOI: 10.1093/nar/gkp577] [Citation(s) in RCA: 160] [Impact Index Per Article: 10.7] [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] [Indexed: 12/27/2022] Open
Abstract
microRNA-155 (miR-155) has been implicated as a central regulator of the immune system, but its function during acute inflammatory responses is still poorly understood. Here we show that exposure of cultured macrophages and mice to lipopolysaccharide (LPS) leads to up-regulation of miR-155 and that the transcription factor c/ebp Beta is a direct target of miR-155. Interestingly, expression profiling of LPS-stimulated macrophages combined with overexpression and silencing of miR-155 in murine macrophages and human monocytic cells uncovered marked changes in the expression of granulocyte colony-stimulating factor (G-CSF), a central regulator of granulopoiesis during inflammatory responses. Consistent with these data, we show that silencing of miR-155 in LPS-treated mice by systemically administered LNA-antimiR results in derepression of the c/ebp Beta isoforms and down-regulation of G-CSF expression in mouse splenocytes. Finally, we report for the first time on miR-155 silencing in vivo in a mouse inflammation model, which underscores the potential of miR-155 antagonists in the development of novel therapeutics for treatment of chronic inflammatory diseases.
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Affiliation(s)
- Jesper Worm
- Santaris Pharma, Kogle Allé 6, DK-2970 Hørsholm, Denmark
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12
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Hedtjärn M, Worm J, Frydenlund Hansen H, Koch T, Ørum H, Hansen J. 302 POSTER Identification of novel and potent RNA inhibitors of ErbB3, based on Locked Nucleic Acid (LNA) technology. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)72236-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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13
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de la Roche M, Worm J, Bienz M. The function of BCL9 in Wnt/beta-catenin signaling and colorectal cancer cells. BMC Cancer 2008; 8:199. [PMID: 18627596 PMCID: PMC2478683 DOI: 10.1186/1471-2407-8-199] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.6] [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: 04/16/2008] [Accepted: 07/15/2008] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Most cases of colorectal cancer are initiated by hyperactivation of the Wnt/beta-catenin pathway due to mutations in the APC tumour suppressor, or in beta-catenin itself. A recently discovered component of this pathway is Legless, which is essential for Wnt-induced transcription during Drosophila development. Limited functional information is available for its two mammalian relatives, BCL9 and B9L/BCL9-2: like Legless, these proteins bind to beta-catenin, and RNAi-mediated depletion of B9L/BCL9-2 has revealed that this protein is required for efficient beta-catenin-mediated transcription in mammalian cell lines. No loss-of-function data are available for BCL9. METHODS We have used overexpression of dominant-negative forms of BCL9, and RNAi-mediated depletion, to study its function in human cell lines with elevated Wnt pathway activity, including colorectal cancer cells. RESULTS We found that BCL9 is required for efficient beta-catenin-mediated transcription in Wnt-stimulated HEK 293 cells, and in the SW480 colorectal cancer cell line whose Wnt pathway is active due to APC mutation. Dominant-negative mutants of BCL9 indicated that its function depends not only on its beta-catenin ligand, but also on an unknown ligand of its C-terminus. Finally, we show that BCL9 and B9L are both Wnt-inducible genes, hyperexpressed in colorectal cancer cell lines, indicating that they are part of a positive feedback loop. CONCLUSION BCL9 is required for efficient beta-catenin-mediated transcription in human cell lines whose Wnt pathway is active, including colorectal cancer cells, indicating its potential as a drug target in colorectal cancer.
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Affiliation(s)
- Marc de la Roche
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, UK.
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14
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Obad S, Worm J, Elmén J, Lindow M, Frydenlund H, Kauppinen S. Targeting of cancer-associated microRNAs using short LNA-antimiR oligonucleotides. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)71721-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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15
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Leser T, Knarreborg A, Worm J. Germination and outgrowth of Bacillus subtilis and Bacillus licheniformis spores in the gastrointestinal tract of pigs. J Appl Microbiol 2008; 104:1025-33. [DOI: 10.1111/j.1365-2672.2007.03633.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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16
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Kastrup IB, Worm J, Ralfkiaer E, Hokland P, Guldberg P, Grønbaek K. Genetic and epigenetic alterations of the reduced folate carrier in untreated diffuse large B-cell lymphoma. Eur J Haematol 2007; 80:61-6. [PMID: 18028428 DOI: 10.1111/j.1600-0609.2007.00980.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reduced folate carrier (RFC) is a transmembrane protein that mediates cellular uptake of reduced folates and antifolate drugs, including methotrexate (MTX). Acquired alterations of the RFC gene have been associated with resistance to MTX in cancer cell lines and primary osteosarcomas. Here, we examined RFC for mutations and promoter hypermethylation in (i) the inherently MTX-resistant lymphoma cell line (RL); (ii) 30 paired cases of acute lymphoblastic leukemia (ALL) obtained at diagnosis and at relapse after treatment with MTX; and (iii) 25 cases of diffuse large B-cell lymphoma (DLBCL) at diagnosis, none of which had been previously exposed to MTX. Aberrant hypermethylation of the RFC promoter occurred in RL cells and two of the primary DLBCLs. In one additional DLBCL, a single-base substitution in RFC was identified, leading to the introduction of a premature termination codon (c.1396C>T; p.Q466X). A missense mutation affecting the 11th transmembrane domain of RFC (c.1250T>C; p.I417T) was found in one case of ALL at diagnosis. In ALL, RFC promoter hypermethylation was found neither at diagnosis nor at relapse and thus is not a common cause of low levels of RFC expression associated with adverse outcome. In DLBCL, genetic and epigenetic alterations of RFC were detected at diagnosis in the absence of a selective MTX pressure, suggesting that these alterations may possibly contribute to the development of lymphoma.
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17
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Juncker-Jensen A, Lykkesfeldt AE, Worm J, Ralfkiaer U, Espelund U, Jepsen JS. Insulin-like growth factor binding protein 2 is a marker for antiestrogen resistant human breast cancer cell lines but is not a major growth regulator. Growth Horm IGF Res 2006; 16:224-239. [PMID: 16893667 DOI: 10.1016/j.ghir.2006.06.005] [Citation(s) in RCA: 32] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Antiestrogens target the estrogen receptor and counteract the growth stimulatory action of estrogen on human breast cancer. However, acquired resistance to antiestrogens is a major clinical problem in endocrine treatment of breast cancer patients. To mimic acquired resistance, we have used a model system with the antiestrogen sensitive human breast cancer cell line MCF-7 and several antiestrogen resistant cell lines derived from the parental MCF-7 cell line. This model system was used to study the expression and possible involvement in resistant cell growth of insulin-like growth factor binding protein 2 (IGFBP-2). By an oligonucleotide based microarray, we compared the expression of mRNAs encoding insulin-like growth factor binding protein 1,2,3,4,5 and 6 (IGFBP-1 to -6) in the parental MCF-7 cell line to three human breast cancer cell lines, resistant to the antiestrogen ICI 182,780 (Faslodex/Fulvestrant). Only IGFBP-2 mRNA was overexpressed in all three resistant cell lines. Thus, we compared the IGFBP-2 protein expression in MCF-7 cells to nine antiestrogen resistant breast cancer cell lines, resistant to either ICI 182,780 or tamoxifen or RU 58,668 and found that IGFBP-2 was overexpressed in all nine resistant cell lines. Three of the resistant cell lines, resistant to different antiestrogens, were selected for further studies and IGFBP-2 overexpression was demonstrated at the mRNA level as well as the intra- and extracellular protein level. The objective of this study was to examine if IGFBP-2 is involved in growth of antiestrogen resistant human breast cancer cells. Therefore, IGFBP-2 expression was inhibited by antisense oligonucletides and siRNA. Specific inhibition of IGFBP-2 protein expression was achieved in MCF-7 and the three selected antiestrogen resistant cell lines, but no effect on resistant cell growth was observed. Thus, we were able to establish IGFBP-2 as a marker for antiestrogen resistant breast cancer cell lines, although IGFBP-2 was not a major contributor to the resistant cell growth.
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Affiliation(s)
- A Juncker-Jensen
- Department of Tumor Endocrinology, Institute of Cancer Biology, Danish Cancer Society, Strandboulevarden 49, DK-2100 Copenhagen, Denmark
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18
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Gao S, Worm J, Guldberg P, Eiberg H, Krogdahl A, Sørensen JA, Liu CJ, Reibel J, Dabelsteen E. Loss of heterozygosity at 9q33 and hypermethylation of the DBCCR1 gene in oral squamous cell carcinoma. Br J Cancer 2004; 91:760-4. [PMID: 15226771 PMCID: PMC2364803 DOI: 10.1038/sj.bjc.6601980] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
The DBCCR1 gene at chromosome 9q33 has been identified as a candidate tumour suppressor, which is frequently targeted by promoter hypermethylation in bladder cancer. Here, we studied the possible involvement of DBCCR1 in the development of oral squamous cell carcinoma. DNA from 34 tumours was examined for loss of heterozygosity (LOH) at three markers surrounding DBCCR1 and for hypermethylation of the DBCCR1 promoter, using methylation-specific PCR and methylation-specific melting-curve analysis. LOH was found in 10 of 31 cases (32%), and DBCCR1 hypermethylation was present in 15 of 34 cases (44%). Hypermethylation of DBCCR1 was also present in three of seven epithelial tissues adjacent to the tumours, including two hyperplastic and one histologically normal epithelia. Furthermore, of four oral leukoplakias with dysplasia, one showed LOH at 9q33 and two showed DBCCR1 hypermethylation. These data suggest that LOH at 9q33 and hypermethylation of the DBCCR1 promoter are frequent and possibly early events in oral malignant development.
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Affiliation(s)
- S Gao
- Department of Oral Diagnostics, School of Dentistry, University of Copenhagen, Nørre Alle 20, DK-2200 Copenhagen, Denmark
| | - J Worm
- Institute of Cancer Biology, Danish Cancer Society, DK-2100 Copenhagen, Denmark
| | - P Guldberg
- Institute of Cancer Biology, Danish Cancer Society, DK-2100 Copenhagen, Denmark
| | - H Eiberg
- Institute of Medical Biochemistry and Genetics, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - A Krogdahl
- Department of Pathology, Odense University Hospital, DK-5000 Odense, Denmark
| | - J A Sørensen
- Department of Plastic Surgery, Odense University Hospital, DK-5000 Odense, Denmark
| | - C-J Liu
- Department of Dentistry, Mackay Memorial Hospital, Taipei
| | - J Reibel
- Department of Oral Diagnostics, School of Dentistry, University of Copenhagen, Nørre Alle 20, DK-2200 Copenhagen, Denmark
| | - E Dabelsteen
- Department of Oral Diagnostics, School of Dentistry, University of Copenhagen, Nørre Alle 20, DK-2200 Copenhagen, Denmark
- Department of Oral Diagnostics, School of Dentistry, University of Copenhagen, Nørre Alle 20, DK-2200 Copenhagen, Denmark. E-mail:
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19
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Abstract
High levels of beta-catenin and activating mutations in the beta-catenin gene (CTNNB1) have been demonstrated in malignant melanomas, implicating dysregulated Wnt signalling in the pathogenesis of this malignancy. We systematically examined melanoma cell lines for activating CTNNB1 mutations as well as genetic and epigenetic alterations of the adenomatous polyposis coli gene (APC), another key component of the Wnt signalling transduction pathway. Of 40 cell lines tested, one carried a truncating APC mutation and loss of the corresponding wild-type allele, and one carried a CTNNB1 missense mutation. Hypermethylation of APC promoter 1A was present in five of the cell lines (13%) and in nine of 54 melanoma biopsies (17%). Cells with truncating APC or activating CTNNB1 mutations showed increased transcription from endogenous and ectopic beta-catenin/T-cell factor (Tcf)-responsive target genes, consistent with the known effects of these alterations on beta-catenin stability and Tcf transactivation. In contrast, cell lines with APC promoter 1A hypermethylation did not show increased Wnt signalling, probably due to residual APC activity expressed from promoter 1B. Suppression of APC transcripts in melanoma cells by stable expression of short hairpin RNAs led to a Wnt signalling-independent increase in cell proliferation, but also reduced the invasive growth in collagen type I. Collectively, our data suggest that the tumour-suppressive function of APC in melanocytic cells is dose dependent. We propose that epigenetic silencing of promoter 1A may contribute to the development of malignant melanoma by reducing the expression of APC to a level that promotes cell proliferation without compromising the invasive capacity.
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MESH Headings
- Adenomatous Polyposis Coli Protein/genetics
- Alleles
- Biopsy
- Cell Division
- Cell Line, Tumor
- Cells, Cultured
- Collagen Type I/metabolism
- Cytoskeletal Proteins
- DNA Methylation
- DNA Mutational Analysis
- Epistasis, Genetic
- Gene Expression Regulation, Neoplastic
- Genes, APC
- Genes, Reporter
- Genetic Variation
- Humans
- Luciferases/metabolism
- Melanocytes/metabolism
- Melanocytes/pathology
- Melanoma/genetics
- Melanoma/metabolism
- Melanoma/pathology
- Mutation, Missense
- Neoplasm Invasiveness
- Promoter Regions, Genetic
- Proto-Oncogene Proteins/metabolism
- RNA Interference
- Sequence Analysis, DNA
- Sequence Deletion
- Trans-Activators
- Transcription, Genetic
- Transcriptional Activation
- Wnt Proteins
- beta Catenin
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Affiliation(s)
- Jesper Worm
- Institute of Cancer Biology, Danish Cancer Society, Strandboulevarden 49, DK-2100 Copenhagen, Denmark
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20
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Gao S, Worm J, Guldberg P, Eiberg H, Krogdahl A, Liu CJ, Reibel J, Dabelsteen E. Genetic and epigenetic alterations of the blood group ABO gene in oral squamous cell carcinoma. Int J Cancer 2004; 109:230-7. [PMID: 14750174 DOI: 10.1002/ijc.11592] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Loss of histo-blood group A and B antigen expression is a frequent event in oral carcinomas and is associated with decreased activity of glycosyltransferases encoded by the ABO gene. We examined 30 oral squamous cell carcinomas for expression of A and B antigens and glycosyltransferases. We also examined DNA from these tumors for loss of heterozygosity (LOH) at markers surrounding the ABO locus at chromosome 9q34, for loss of specific ABO alleles, and for hypermethylation of the ABO promoters. Loss of A or B antigen expression was found in 21 of 25 tumors (84%) and was a consistent feature of tumors lacking expression of A/B glycosyltransferases. LOH at 9q34 was found in 7 of 27 cases (26%), and one case showed microsatellite instability. Among 20 AO/BO cases, 3 showed loss of the A/B allele and 3 showed loss of the O allele. Analysis of the proximal ABO promoter by methylation-specific PCR and melting curve analysis showed hypermethylation in 10 of 30 tumors (33.3%), which was associated with loss of A/B antigen expression. ABO promoter hypermethylation was also found in hyperplastic or dysplastic tissues adjacent to the tumors, suggesting that it is an early event in tumorigenesis. Collectively, we have identified molecular events that may account for loss of A/B antigen expression in 67% of oral squamous cell carcinomas.
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Affiliation(s)
- Shan Gao
- School of Dentistry, University of Copenhagen, Denmark
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21
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Löffler H, Syljuåsen RG, Bartkova J, Worm J, Lukas J, Bartek J. Distinct modes of deregulation of the proto-oncogenic Cdc25A phosphatase in human breast cancer cell lines. Oncogene 2003; 22:8063-71. [PMID: 14603247 DOI: 10.1038/sj.onc.1206976] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The rapid cell cycle arrest in response to DNA damage is mediated by degradation of the Cdc25A phosphatase, a proto-oncogene whose mRNA is frequently overexpressed in human tumours. Here, we study the occurrence and mechanisms of Cdc25A deregulation in human breast cancer cell lines. We demonstrate aberrantly elevated Cdc25A protein abundance and phosphatase activity in eight out of 15 cell lines, in some cases resulting in abrogation of the Cdc25A-mediated checkpoint response to ionizing radiation (IR), and this defect correlated with hypersensitivity to IR. Furthermore, we present evidence that deregulation of Cdc25A occurs predominantly on the post-transcriptional level, as overabundant Cdc25A protein was usually not accompanied by adequate mRNA overexpression. Instead, we demonstrate that aberrantly enhanced protein stability is an important mechanism underlying Cdc25A overabundance in a subset of breast cancer cell lines. Given the frequency of this mechanism, we propose that the DNA integrity checkpoint controlling Cdc25A protein stability might be a common target for deregulation in breast cancer.
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Affiliation(s)
- Harald Löffler
- Institute of Cancer Biology, Danish Cancer Society, Strandboulevarden 49, DK-2100 Copenhagen, Denmark
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22
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Abstract
The unique properties of a cancer cell are acquired through a stepwise accumulation of heritable changes in the information content of proto-oncogenes and tumor suppressor genes. While gain, loss, and mutation of genetic information have long been known to contribute to tumorigenesis, it has been increasingly recognized over the past 5 years that 'epigenetic' mechanisms may play an equally important role. The main epigenetic modification of the human genome is methylation of cytosine residues within the context of the CpG dinucleotide. De novo methylation of 'CpG islands' in the promoter regions of tumor suppressor genes may lead to transcriptional silencing through a complex process involving histone deacetylation and chromatin condensation, and thus represents a tumorigenic event that is functionally equivalent to genetic changes like mutation and deletion. DNA methylation is interesting from a diagnostic viewpoint because it may be easily detected in DNA released from neoplastic and preneoplastic lesions into serum, urine or sputum, and from a therapeutic viewpoint because epigenetically silenced genes may be reactivated by inhibitors of DNA methylation and/or histone deacetylase. A better understanding of epigenetic mechanisms leading to tumor formation and chemoresistance may eventually improve current cancer treatment regimens and be instructive for a more rational use of anticancer agents.
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Affiliation(s)
- Jesper Worm
- Institute of Cancer Biology, Danish Cancer Society, Strandboulevarden 49, DK-2100 Copenhagen, Denmark
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23
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Grønbaek K, Worm J, Ralfkiaer E, Ahrenkiel V, Hokland P, Guldberg P. ATM mutations are associated with inactivation of the ARF-TP53 tumor suppressor pathway in diffuse large B-cell lymphoma. Blood 2002; 100:1430-7. [PMID: 12149228 DOI: 10.1182/blood-2002-02-0382] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [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] Open
Abstract
The ATM serine-threonine kinase plays a central role in the cellular response to DNA damage. Germ-line mutations in the ATM gene cause ataxia-telangiectasia (A-T), a multisystem disorder associated with predisposition to lymphoma and acute leukemia. Moreover, somatic ATM mutations have been identified in T-cell prolymphocytic leukemia, mantle cell lymphoma, and B-cell chronic lymphocytic leukemia. In this study, the entire ATM coding sequence was examined in genomic DNA from 120 lymphoid neoplasms. Novel mutations and mutations implicated in cancer and/or A-T were found in 9 of 45 diffuse large B-cell lymphomas (DLBCLs), 2 of 24 follicular lymphomas, and 1 of 27 adult acute lymphoblastic leukemias, whereas no such mutations were detected among 24 peripheral T-cell lymphomas. The mutational spectrum consisted of 2 nonsense mutations, 1 mutation affecting RNA splicing, and 10 missense variants. Most of these mutations were associated with loss or mutation of the paired ATM allele, consistent with biallelic inactivation of ATM. Of the 9 DLBCLs with ATM mutations, 7 also carried TP53 mutations and/or deletions of the INK4a/ARF locus (P =.003). The ATM 735C>T substitution previously considered a rare normal variant was found to be 5.6 times more frequent in individuals with DLBCL than in random individuals (P =.026), suggesting that it may predispose to B-cell lymphoma. Our data suggest that ATM mutations contribute to the development of DLBCL, and that ATM and the ARF-p53 tumor suppressor pathway may cooperate in the pathogenesis of this malignancy.
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Affiliation(s)
- Kirsten Grønbaek
- Institute of Cancer Biology, Danish Cancer Society, Copenhagen, Denmark
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24
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Abstract
The idea of modifying DNA with bisulfite has paved the way for a variety of polymerase chain reaction (PCR) methods for accurately mapping 5-methylcytosine at specific genes. Bisulfite selectively deaminates cytosine to uracil under conditions where 5-methylcytosine remains unreacted. Following conventional PCR amplification of bisulfite-treated DNA, original cytosines appear as thymine while 5-methylcytosines appear as cytosine. Because the relative thermostability of a DNA duplex increases with increasing content of G:C base pairs, PCR products originating from DNA templates with different contents of 5-methylcytosine differ in melting temperature, i.e., the temperature required to convert the double helix into random coils. We describe two methods that resolve differentially methylated DNA sequences on the basis of differences in melting temperature. The first method integrates PCR amplification of bisulfite-treated DNA and subsequent melting analysis by using a thermal cycler coupled with a fluorometer. By including in the reaction a PCR-compatible, fluorescent dye that specifically binds to double-stranded DNA, the melting properties of the PCR product can be examined directly in the PCR tube by continuous fluorescence monitoring during a temperature transition. The second method relies on resolution of alleles with different 5-methylcytosine contents by analysis of PCR products in a polyacrylamide gel containing a gradient of chemical denaturants. Optimal resolution of differences in melting temperature is achieved by a special design of PCR primers. Both methods allow resolution of "heterogeneous" methylation, i.e., the situation where the content and distribution of 5-methylcytosine in a target gene differ between different molecules in the same sample.
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Affiliation(s)
- Per Guldberg
- Institute of Cancer Biology, Danish Cancer Society, Strandboulevarden 49, DK-2100 Copenhagen, Denmark.
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25
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Guldberg P, Grønbaek K, Worm J, thor Straten P, Zeuthen J. Mutational analysis of oncogenes and tumor suppressor genes in human cancer using denaturing gradient gel electrophoresis. Methods Mol Med 2002; 68:125-39. [PMID: 11901498 DOI: 10.1385/1-59259-135-3:125] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Affiliation(s)
- Per Guldberg
- Department of Tumour Cell Biology, Institute of Cancer Biology, Danish Cancer Society, Copenhagen, Denmark
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26
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Abstract
The objective of this study was to determine how an input of protein to lake water affects expression of a proteolytic potential and influences the abundance and composition of a specific group of bacteria. Pseudomonas spp. were chosen as a target group that can be recovered on selective growth media and contain both proteolytic and nonproteolytic strains. Amendment with 2 mg of casein per liter increased total proteinase activity (hydrolysis of [(3)H]casein) by 74%, leucine-aminopeptidase activity (hydrolysis of leucine-methyl-coumarinylamide) by 133%, bacterial abundance by 44%, and phytoplankton biomass (chlorophyll a) by 39%. The casein amendment also increased the abundance of culturable Pseudomonas spp. by fivefold relative to control microcosms but did not select for proteolytic isolates. Soluble proteins immunochemically related to the Pseudomonas fluorescens alkaline proteinase, AprX, were detected in amended microcosms but not in the controls. The expression of this class of proteinase was confirmed exclusively for proteolytic Pseudomonas isolates from the microcosms. The population structure of Pseudomonas isolates was determined from genomic fingerprints generated by universally primed PCR, and the analysis indicated that casein amendment led to only minor shifts in population structure. The appearance of AprX-like proteinases in the lake water might thus reflect a general induction of enzyme expression rather than pronounced shifts in the Pseudomonas population structure. The limited effect of casein amendment on Pseudomonas population structure might be due to the availability of casein hydrolysates to bacteria independent of their proteinase expression. In the lake water, 44% of the total proteinase activity was recovered in 0.22-microm-pore-size filtrates and thus without a direct association with the bacteria providing the extracellular enzyme activity. Since all Pseudomonas isolates expressed leucine-aminopeptidase in pure culture, proteolytic as well as nonproteolytic pseudomonads were likely members of the bacterial consortium that metabolized protein in the lake water.
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Affiliation(s)
- J Worm
- Section of Genetics and Microbiology, Department of Ecology, The Royal Veterinary and Agricultural University, DK-1871 Frederiksberg C, Denmark.
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Worm J, Kirkin AF, Dzhandzhugazyan KN, Guldberg P. Methylation-dependent silencing of the reduced folate carrier gene in inherently methotrexate-resistant human breast cancer cells. J Biol Chem 2001; 276:39990-40000. [PMID: 11509559 DOI: 10.1074/jbc.m103181200] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.7] [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: 11/06/2022] Open
Abstract
The molecular basis of methotrexate resistance was studied in human MDA-MB-231 breast cancer cells, which are inherently defective in methotrexate uptake and lack expression of the reduced folate carrier (RFC). Transfection of MDA-MB-231 cells with RFC cDNA restored methotrexate uptake and increased methotrexate sensitivity by approximately 50-fold. A CpG island in the promoter region of RFC was found to be methylated in MDA-MB-231 cells, but was unmethylated in RFC expressing, methotrexate-sensitive MCF-7 breast cancer cells. Chromatin immunoprecipitation with antibodies against acetylated histones H3 and H4 showed that the RFC promoter was enriched for acetylated histones on expressed, unmethylated alleles only. Treatment of MDA-MB-231 cells with 5-aza-2'-deoxycytidine restored RFC expression but also led to increased methotrexate efflux and did not reverse methotrexate resistance. This suggests that 5-aza-2'-deoxycytidine up-regulates both methotrexate uptake and some methotrexate-resistance mechanism(s). Reverse transcription-polymerase chain reaction analysis showed increased expression levels of several ATP-dependent efflux pumps in response to 5-aza-2'-deoxycytidine treatment, including P-glycoprotein and members of the multidrug resistance-associated protein family. Up-regulation of P-glycoprotein in response to 5-aza-2'-deoxycytidine was associated with demethylation of a CpG island in the MDR1 promoter, whereas the mechanism(s) for 5-aza-2'-deoxycytidine-induced up-regulation of multidrug resistance-associated proteins is probably indirect. Dipyridamole inhibited methotrexate efflux and reversed methotrexate resistance in 5-aza-2'-deoxycytidine-treated MDA-MB-231 cells.
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Affiliation(s)
- J Worm
- Institute of Cancer Biology, Danish Cancer Society, Strandboulevarden 49, DK-2100 Copenhagen, Denmark
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Koch B, Worm J, Jensen LE, Højberg O, Nybroe O. Carbon limitation induces sigma(S)-dependent gene expression in Pseudomonas fluorescens in soil. Appl Environ Microbiol 2001; 67:3363-70. [PMID: 11472905 PMCID: PMC93029 DOI: 10.1128/aem.67.8.3363-3370.2001] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [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] Open
Abstract
Recent studies employing reporter gene technology indicate that the availabilities of the major nutrients nitrogen, phosphate, and iron to Pseudomonas are not severely limited in bulk soil. Indirect evidence has pointed to carbon limitation as a severe nutritional stress in this environment. We show that a plasmid (pGM115)-borne transcriptional fusion between the sigma(S)-dependent Escherichia coli promoter P(fic) and lacZ functions as a reliable reporter for carbon availability in Pseudomonas fluorescens. When P. fluorescens strain DF57(pGM115) was introduced into bulk soil, carbon-limiting conditions were indicated by citrate-repressible induction of beta-galactosidase activity. To address carbon availability at the single-cell level, we developed an immunofluorescence double-staining procedure for individual DF57 cells expressing beta-galactosidase from P(fic). Changes in cell size and expression of beta-galactosidase were analyzed by flow cytometry. Cells extracted from soil microcosms reduced their size less than carbon-starved cells in pure culture and showed an increased tendency to aggregate. The single-cell analysis revealed that for cells residing in soil, the expression of beta-galactosidase became heterogeneous and only a DF57 subpopulation appeared to be carbon limited. In soil amended with barley straw, limited nitrogen availability has been determined by use of the bioluminescent reporter strain P. fluorescens DF57-N3. We used strain DF57-N3(pGM115) as a double reporter for carbon and nitrogen limitation that allowed us to study the dynamics of carbon and nitrogen availabilities in more detail. In straw-amended soil beta-galactosidase activity remained low, while nitrogen limitation-dependent bioluminescence appeared after a few days. Hence, nitrogen became limited under conditions where carbon resources were not completely exhausted.
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Affiliation(s)
- B Koch
- Section of Genetics and Microbiology, Department of Ecology, Royal Veterinary and Agricultural University, DK-1871 Frederiksberg C, Denmark
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29
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Worm J, Aggerholm A, Guldberg P. In-tube DNA methylation profiling by fluorescence melting curve analysis. Clin Chem 2001; 47:1183-9. [PMID: 11427447] [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: 02/20/2023]
Abstract
BACKGROUND Most PCR assays for detection of 5-methylcytosine in genomic DNA entail a two-step procedure, comprising initial PCR amplification and subsequent product analysis in separate operations that usually require manual transfer. These methods generally provide information about methylation of only a few CpG dinucleotides within the target sequence. METHODS An in-tube methylation assay is described that integrates amplification of bisulfite-treated DNA and melting analysis by using a thermal cycler coupled to a fluorometer (LightCycler). DNA melting curves were acquired by measuring the fluorescence of a double-stranded DNA-binding dye (SYBR Green I) during a linear temperature transition. RESULTS Analysis of a region comprising 11 CpG sites at the SNRPN promoter CpG island showed that the melting temperature (T(m)) differed by approximately 3 degrees C between unmethylated and fully methylated alleles. This assay could easily distinguish patients with Prader-Willi syndrome or Angelman syndrome from individuals without these conditions. Melting curve analysis also allowed resolution of methylation "mosaicism" at the p15(Ink4b) promoter in bone marrow samples from patients with acute myeloid leukemia (AML). AML samples representing pools of heterogeneously methylated p15(Ink4b) alleles showed broadened melting peaks with overall T(m)s between those of the unmethylated and fully methylated alleles. CONCLUSIONS Integration of PCR and fluorescence melting analysis may be useful for simple and cost-effective detection of aberrant methylation patterns.
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Affiliation(s)
- J Worm
- Department of Tumor Cell Biology, Institute of Cancer Biology, Danish Cancer Society, Strandboulevarden 49, DK-2100 Copenhagen, Denmark
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Abstract
Abstract
Background: Most PCR assays for detection of 5-methylcytosine in genomic DNA entail a two-step procedure, comprising initial PCR amplification and subsequent product analysis in separate operations that usually require manual transfer. These methods generally provide information about methylation of only a few CpG dinucleotides within the target sequence.
Methods: An in-tube methylation assay is described that integrates amplification of bisulfite-treated DNA and melting analysis by using a thermal cycler coupled to a fluorometer (LightCycler). DNA melting curves were acquired by measuring the fluorescence of a double-stranded DNA-binding dye (SYBR Green I) during a linear temperature transition.
Results: Analysis of a region comprising 11 CpG sites at the SNRPN promoter CpG island showed that the melting temperature (Tm) differed by ∼3 °C between unmethylated and fully methylated alleles. This assay could easily distinguish patients with Prader-Willi syndrome or Angelman syndrome from individuals without these conditions. Melting curve analysis also allowed resolution of methylation “mosaicism” at the p15Ink4b promoter in bone marrow samples from patients with acute myeloid leukemia (AML). AML samples representing pools of heterogeneously methylated p15Ink4b alleles showed broadened melting peaks with overall Tms between those of the unmethylated and fully methylated alleles.
Conclusions: Integration of PCR and fluorescence melting analysis may be useful for simple and cost-effective detection of aberrant methylation patterns.
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Affiliation(s)
- Jesper Worm
- Department of Tumor Cell Biology, Institute of Cancer Biology, Danish Cancer Society, Strandboulevarden 49, DK-2100 Copenhagen, Denmark
| | - Anni Aggerholm
- Department of Haematology, Aarhus University Hospital, Tage-Hansens Gade 2, DK-8000 Aarhus C, Denmark
| | - Per Guldberg
- Department of Tumor Cell Biology, Institute of Cancer Biology, Danish Cancer Society, Strandboulevarden 49, DK-2100 Copenhagen, Denmark
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Abstract
Once-through, plug-flow bioreactors were colonised and maintained with a microbial community from a mesotrophic lake and used to measure the concentration of biodegradable dissolved organic carbon (BDOC). A BDOC measurement can be done within 3-4h by this method. Glucose was used to test whether oxygen consumption (BOD) could substitute for measurements of dissolved organic carbon (DOC). All added glucose was utilised, however, without a concomitant increase in oxygen demand. Oxygen consumption should not be used in bioreactor measurements. The site-specificity was tested by comparing DOC utilisation in bioreactors with batch cultures inoculated with indigenous bacteria and incubated for 28 days. The bioreactors were not site-specific and required no acclimation to measure BDOC from three different systems. However, humic substances were adsorbed in the reactors and about two days were needed to equilibrate the reactors. The BDOC concentrations in two lakes varied 2-fold over diurnal cycles and 3-fold during the period February-June. No significant relations to the light, dark cycle, chlorophyll, and DOC were found. The absolute BDOC concentrations ranged from 20 to almost 200 microM and averaged 13% of the DOC in the lakes. It is concluded that BDOC in lakes and other fresh waters can be measured quickly and reliably with a bioreactor.
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Affiliation(s)
- M Søndergaard
- Freshwater Biological Laboratory, University of Copenhagen, Hillerød, Denmark.
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Abstract
p27Kip1 is a regulator of the mammalian cell cycle and a putative tumor suppressor. Distinct altered patterns of p27Kip1 protein expression are found in a variety of human carcinomas, and p27Kip1 expression levels usually correlate directly with disease-free survival. The mechanism(s) by which p27Kip1 expression is reduced or lost during tumorigenesis remains unclear. Specific alterations of the p27Kip1 gene, including mutations and homozygous deletions, are exceedingly rare in human cancers. We have used methylation-specific PCR and bisulfite genomic sequencing to examine the methylation status of p27Kip1 in 61 primary and metastatic tumors and 35 cell lines from patients with malignant melanoma. Dense methylation of a CpG island in the promoter region of p27Kip1 was detected in four of 45 metastatic tumors (9%) and three of the cell lines (9%), including two cell lines established from two different metastases from the same patient. Examination of a naturally occurring, allele-specific sequence variant demonstrated that p27Kip1 methylation is associated with transcriptional silencing in situ. Cell lines with p27Kip1 methylation showed retention of the wild-type allele and detectable p27Kip1 protein whose abundance was reduced compared with normal melanocytes. Collectively, our data suggest that DNA methylation may be a cause of monoallelic p27Kip1 silencing in malignant melanoma, which would support a role for p27Kip1 haploinsufficiency in human cancer.
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Affiliation(s)
- J Worm
- Institute of Cancer Biology, Danish Cancer Society, Copenhagen, Denmark
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Worm J, Jensen LE, Hansen TS, Søndergaard M, Nybroe O. Interactions between proteolytic and non-proteolytic Pseudomonas fluorescens affect protein degradation in a model community. FEMS Microbiol Ecol 2000; 32:103-109. [PMID: 10817863 DOI: 10.1111/j.1574-6941.2000.tb00704.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The metabolic interactions between proteinase-producing bacteria and other members of bacterial communities are poorly investigated, although they are important for the understanding of structure-function relationships in complex ecosystems. We constructed simple model communities consisting of proteolytic and non-proteolytic Pseudomonas fluorescens strains to identify relevant interactions and to assess their specific significance during the mobilization of protein for growth. The proteolytic or non-proteolytic model communities were established by co-inoculating proteolytic or proteinase-deficient Tn5-mutants of P. fluorescens strain ON2 with the non-proteolytic reporter strain DF57-N3 that expresses bioluminescence in response to nitrogen limitation. The growth medium was composed such that growth would be nitrogen limited in the absence of proteolytic activity. In the proteolytic communities data on growth and nitrogen availability showed that the protein hydrolysates were available to both the proteolytic and the non-proteolytic strain. Competition between these strains profoundly affected both growth and proteinase production. Hence, the mobilization of protein was closely coupled to the competitive success of the proteolytic strain. These findings provide new insight into the metabolic interactions that occur when protein is degraded in mixed bacterial communities.
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Affiliation(s)
- J Worm
- Department of Ecology, Royal Veterinary and Agricultural University, Thorvaldsensvej 40, DK-1871, Frederiksberg, Denmark
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34
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Rosholm JU, Bjerrum L, Hallas J, Worm J, Gram LF. Polypharmacy and the risk of drug-drug interactions among Danish elderly. A prescription database study. Dan Med Bull 1998; 45:210-3. [PMID: 9587704] [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: 02/07/2023]
Abstract
OBJECTIVE To analyze the use of all subsidized prescription drugs with special attention to the elderly (> or = 70 years of age), including their use of drug combination generally accepted as carrying a risk of severe interactions. DESIGN Descriptive prevalence study. SETTING Odense Pharmacoepidemiological Database, Denmark. The fourth quarter of 1994. SUBJECTS All inhabitants in the county of Funen, Denmark. MAIN OUTCOME MEASURES Prevalence of drug use for persons < 70 and > or = 70 years of age including number of drugs used and of drug combinations. Occurrence of 45 drug combinations generally accepted as carrying a risk of severe interactions. RESULTS Among persons less than 70 years, 67.9% used none, 16.5% used one drug and 15.6% used two or more prescription drugs. The corresponding prevalences for the elderly were 35.7%, 15.9% and 48.4%. The 26,337 elderly patients with at least two drugs used 21,293 different combinations. Of the elderly patients who had purchased > or = two drugs, 4.4% had combinations of drugs carrying a risk of severe interactions. CONCLUSIONS Most elderly use drugs and usually several drugs concomitantly. The elderly form a heterogeneous group of drug users. Drug combinations carrying a risk of severe interactions are relatively frequent.
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Affiliation(s)
- J U Rosholm
- Department of Clinical Pharmacology, IMB, Odense University Hospital
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35
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Hallas J, Harvald B, Worm J, Beck-Nielsen J, Gram LF, Grodum E, Damsbo N, Schou J, Kromann-Andersen H, Frølund F. Drug related hospital admissions. Results from an intervention program. Eur J Clin Pharmacol 1993; 45:199-203. [PMID: 8276041 DOI: 10.1007/bf00315383] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.1] [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: 01/29/2023]
Abstract
As part of a high-intensity monitoring study of drug events as the cause of admission to departments of internal medicine, the effect of an educational intervention programme was studied. Two departments were included, one specialising in geriatrics and one that received patients by non-selected referral. The series consisted of 607 consecutive admissions studied before and 703 after the intervention. The drug events considered were adverse drug reactions and dose-related therapeutic failures, mainly due to non-compliance. A modest, statistically non-significant decrease in drug related hospital admissions (DRH) was seen, from 14% before to 13% after the intervention period. However, DRHs classified as definitely avoidable showed the significant decrease of 83%. There was no apparent relationship between the topics selected for the intervention programme and changes in the pattern of DRHs. No relationship between alterations in sales data and hospital admissions caused by a given drug could be demonstrated. A blinded external evaluation of case abstracts did not disclose any significant shift in the investigators' assessments. The intervention may have had an non-specific effect on avoidable DRHs.
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Affiliation(s)
- J Hallas
- Department of Clinical Pharmacology, Institute of Medical Biology, Odense, Denmark
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36
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Kronborg O, Fenger C, Worm J, Pedersen SA, Hem J, Bertelsen K, Olsen J. Causes of death during the first 5 years of a randomized trial of mass screening for colorectal cancer with fecal occult blood test. Scand J Gastroenterol 1992; 27:47-52. [PMID: 1736342 DOI: 10.3109/00365529209011166] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The main purpose of population screening for colorectal cancer is to reduce mortality from the disease. The criteria of death from colorectal cancer are defined in the present randomized trial of 61,938 persons between 45 and 74 years old, and the need for an impartial death review committee was demonstrated. Causes of death within the first 5 years are described within subgroups of the test group and compared with those in the control group. Death rates were higher among non-responders to screening than among controls and among those in whom Hemoccult-II had been performed at least once. Persons with negative Hemoccult-II had a lower death rate than controls. The overall autopsy rate was 32%. Lethal complications from treatment of colorectal neoplasia were evaluated per se. Death from colorectal cancer occurred in 74 persons in the total screening group and in 91 among controls. Sources of bias are discussed. A method of evaluating possible benefit to those being screened is suggested. Final results cannot be expected before 1996.
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Affiliation(s)
- O Kronborg
- Dept. of Surgical Gastroenterology, Odense University Hospital, Denmark
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37
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Hallas J, Gram LF, Grodum E, Damsbo N, Brøsen K, Haghfelt T, Harvald B, Beck-Nielsen J, Worm J, Jensen KB. Drug related admissions to medical wards: a population based survey. Br J Clin Pharmacol 1992; 33:61-8. [PMID: 1540492 PMCID: PMC1381200 DOI: 10.1111/j.1365-2125.1992.tb04001.x] [Citation(s) in RCA: 137] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
1. In total 1999 consecutive admissions to six medical wards were subjected to a prospective high-intensity drug event monitoring scheme to assess the extent and pattern of admissions caused by adverse drug reactions (ADRs) or dose related therapeutic failures (TF), in a population-based design. The wards were sub-specialised in general medicine, geriatrics, endocrinology, cardiology, respiratory medicine and gastroenterology. 2. Considering definite, probable and possible drug events, the prevalence of drug related hospital admissions was 11.4% of which 8.4% were caused by ADRs and 3.0% by TFs. There were large inter-department differences. 3. The six classes of drugs most frequently involved in admissions caused by ADRs were anti-rheumatics and analgesics (27%), cardiovascular drugs (23%), psychotropic drugs (14%), anti-diabetics (12%), antibiotics (7%), and corticosteroids (5%). Noncompliance accounted for 66% of the TFs with diuretics and anti-asthmatics most frequently involved. 4. The pattern of drugs involved in ADRs was compared with the regional drug sales statistics. Drugs with a particularly high rate of ADR related admissions per unit dispensed were nitrofurantoin and insulin (617 and 182 admissions per 1,000,000 defined daily doses), while low rates were seen for diuretics and benzodiazepines (10 and 7 admissions per 1,000,000 defined daily doses). Confidence intervals were wide. 5. Patients who had their therapy prescribed by a hospital doctor had a slightly higher prevalence of drug events than those who were treated by a general practitioner (12.6% vs 11.8%). The reverse applied for drug events assessed as avoidable (3.3% vs 4.6%). Although these differences were not statistically significant, it may suggest general practitioners as the appropriate target for interventive measures.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J Hallas
- Department of Clinical Pharmacology, Odense University School of Medicine, Denmark
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38
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Hallas J, Worm J, Beck-Nielsen J, Gram LF, Grodum E, Damsbo N, Brøsen K. Drug related events and drug utilization in patients admitted to a geriatric hospital department. Dan Med Bull 1991; 38:417-20. [PMID: 1802630] [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: 12/28/2022]
Abstract
Two hundred ninety-four consecutive admissions to a geriatric department were evaluated for drug events as cause of admission. The drug events considered were adverse drug reactions (ADRs) and dose-related therapeutic failures. In 39 cases (13.3%), a definite, probable or possible drug event was a dominant or contributing cause of the admission (11.2% ADRs and 2.0% dose-related therapeutic failures). Five of these cases (1.7%) were judged to be due to errors in prescription and a further seven (2.4%) were found to have been avoidable by efforts exceeding the obligatory. There were no statistically significant differences between drug-related and non-drug related admissions in terms of age, sex, number of drugs taken at the admission or duration of hospitalization. ADRs in the geriatric patients are difficult to recognize and may be interpreted as senile loss of function. Sixty-seven percent of the patients took drugs with a sedative action, 68% took drugs with a hypotensive action, 67% took drugs with a potential for confusional states, 15% took drugs with a potential for depression, and 64% took drugs with a potential for constipation. A reduction of the number of drug-related hospital admissions by means of a large-scale intervention would be a difficult task for several reasons: no particular class of drugs caused the drug events, no particular mechanism dominated, no particular group of doctors were responsible for the drug events, and only a part of the drug events were judged to be avoidable.
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Affiliation(s)
- J Hallas
- Department of Clinical Pharmacology, Odense Hospital
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39
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Pallisgaard G, Worm J. [Light-induced hypercalcemia as initial symptom in Boeck's sarcoid]. Ugeskr Laeger 1987; 149:2612. [PMID: 3451500] [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: 01/05/2023]
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40
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Worm J. Effect of long-term medical therapy. Dan Med Bull 1982; 29:147-151. [PMID: 6804179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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41
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Worm J. [Treatment of constipation in patients in a nursing home with Vi-Siblin]. Ugeskr Laeger 1980; 142:567-9. [PMID: 6247800] [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: 01/19/2023]
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42
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Krabbe S, Christensen T, Worm J, Christiansen C, Transbøl I. Relationship between haemoglobin and serum testosterone in normal children and adolescents and in boys with delayed puberty. Acta Paediatr Scand 1978; 67:655-8. [PMID: 696311 DOI: 10.1111/j.1651-2227.1978.tb17818.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The concentrations of haemoglobin and of serum testosterone were measured in 215 normal children and adolescents aged 7--20 years, and in 8 boys with constitutional delayed puberty. From the age of 14 years onward haemoglobin and testosterone rose in normal boys and differed significantly from the stable levels observed in prepubertal children and pubertal girls. In the entire series of normal boys (n = 118, age 7--20 years) concentrations of haemoglobin and testosterone were found to be closely correlated (r = 0.73, p less than 0.001). These results provide further evidence for a major role of testosterone in the control of erythropoiesis. Therefore, this correlation suggests the use of serum testosterone determination for the proper selection of haemoglobin reference ranges in boys. The respective reference ranges of haemoglobin corresponding to testosterone levels at 0 and 30 nmol/l were 120.5--148.5 and 143.5--171.5 g/l (95% confidence limits). Boys with delayed puberty were found to have significantly reduced median values of haemoglobin and testosterone for their chronological age, and 6 of the 8 boys investigated were truly anaemic on this background. Nevertheless, their haemoglobin concentration did appear appropriate as judged from their testosterone levels. This observation supports the idea that the selection of the relevant reference range for haemoglobin in boys should depend on the state of physical development as expressed by serum testosterone.
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43
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Mogensen EF, Worm J, Mikkelsen BO. [Clinical comparison between glibornuride (Glutril) and glibenclamide in senile diabetes. A controlled double-blind trial]. Ugeskr Laeger 1976; 138:1569-71. [PMID: 133484] [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: 12/13/2022]
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44
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Mogensen EF, Worm J, Mikkelsen BO. Clinical comparison between glibornuride (Glutril) and glibenclamide in maturity-onset diabetes: a controlled double-blind trial. Curr Ther Res Clin Exp 1976; 19:559-64. [PMID: 132338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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45
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Worm J. [Glibornurid (Glutril, Roche)]. Ugeskr Laeger 1974; 136:2763-4. [PMID: 4446104] [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: 01/10/2023]
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46
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Worm J. [Observation and diagnosis in geriatrics]. Sygeplejersken 1974; 74:42-6. [PMID: 4495888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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47
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Pallisgaard G, Worm J. [Seasonal variation of hypercalcemia in sarcoidosis]. Ugeskr Laeger 1970; 132:1088-92. [PMID: 5419639] [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: 01/15/2023]
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48
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Worm J. [Corynebacterium endocarditis]. Ugeskr Laeger 1968; 130:555-8. [PMID: 5664007] [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: 01/16/2023]
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