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1.
Hum Mol Genet ; 28(21): 3610-3624, 2019 11 01.
Article in English | MEDLINE | ID: mdl-31511867

ABSTRACT

Mucopolysaccharidosis (MPS) type VII is a lysosomal storage disease caused by ß-glucuronidase deficiency, prompting glycosaminoglycan accumulation in enlarged vesicles, leading to peripheral and neuronal dysfunction. Here, we present a gene therapy strategy using lumbar puncture of AAVrh10 encoding human ß-glucuronidase (AAVrh10-GUSB) to adult MPS VII mice. This minimally invasive technique efficiently delivers the recombinant vector to the cerebrospinal fluid (CSF) with a single intrathecal injection. We show that AAVrh10 delivery to the CSF allows global, stable transduction of CNS structures. In addition, drainage of AAVrh10-GUSB from the CSF to the bloodstream resulted in the transduction of somatic organs such as liver, which provided a systemic ß-glucuronidase source sufficient to achieve serum enzyme activity comparable to wild type mice. ß-glucuronidase levels were enough to correct biochemical and histopathological hallmarks of the disease in the CNS and somatic organs at short and long term. Moreover, the progression of the bone pathology was also reduced. Importantly, the biochemical correction led to a significant improvement in the physical, cognitive and emotional characteristics of MPS VII mice, and doubling their life span. Our strategy may have implications for gene therapy in patients with lysosomal storage diseases.


Subject(s)
Dependovirus/genetics , Genetic Therapy , Genetic Vectors/genetics , Mucopolysaccharidosis VII/genetics , Mucopolysaccharidosis VII/therapy , Animals , Behavior, Animal , Cognition , Dependovirus/metabolism , Disease Models, Animal , Emotions , Genetic Vectors/metabolism , Glucuronidase/administration & dosage , Glucuronidase/genetics , Glucuronidase/metabolism , Humans , Male , Mice , Mice, Inbred C57BL , Mice, Inbred ICR , Mucopolysaccharidosis VII/mortality , Mucopolysaccharidosis VII/psychology , Survival
2.
Analyst ; 142(20): 3771-3796, 2017 Oct 09.
Article in English | MEDLINE | ID: mdl-28858342

ABSTRACT

While NMR is the most used analytical method for determining the molecular structure of isolated chemical entities, small compounds as well as macromolecules, its capability of analysing complex mixtures is less known. The advent of Diffusion Ordered SpectroscopY (DOSY) NMR has made diffusion experiments popular, enabling diffusion coefficients to be routinely measured and used to characterize chemical systems in solution. Indeed, since the translational diffusion coefficients of molecular species reflect their effective sizes and shapes, DOSY NMR allows the separation of the chemical entities present in multicomponent systems and, as in all diffusion NMR experiments, provides information on their intermolecular interactions as well as on their size and shape. The main aim of this review is to present an overview of the DOSY NMR mapping and its applications. The paper starts with a brief introduction to pulsed-field gradient (PFG) NMR and then focuses on the methodological procedures that can be used to perform good diffusion data acquisition and to obtain good-quality DOSY maps. The second part describes, through selected literature examples, different applications of DOSY NMR to demonstrate the potential of the method for (i) unravelling the components of complex matrices comprising pharmaceuticals, dietary supplements, foods and beverages, and biological extracts, and (ii) probing intermolecular interactions and evaluating association constants between different hosts and guests, as well as estimating the sizes and molecular weights of molecular species.

3.
Oncogenesis ; 6(7): e354, 2017 Jul 03.
Article in English | MEDLINE | ID: mdl-28671677

ABSTRACT

The proximity of organs at risk makes the treatment of head and neck squamous cell carcinoma (HNSCC) challenging by standard radiotherapy. The higher precision in tumor targeting of proton (P) therapy could promote it as the treatment of choice for HNSCC. Besides the physical advantage in dose deposition, few is known about the biological impact of P versus photons (X) in this setting. To investigate the comparative biological effects of P versus X radiation in HNSCC cells, we assessed the relative biological effectiveness (RBE), viability, proliferation and mRNA levels for genes involved in (lymph)angiogenesis, inflammation, proliferation and anti-tumor immunity. These parameters, particularly VEGF-C protein levels and regulations, were documented in freshly irradiated and/or long-term surviving cells receiving low/high-dose, single (SI)/multiple (MI) irradiations with P/X. The RBE was found to be 1.1 Key (lymph)angiogenesis and inflammation genes were downregulated (except for vegf-c) after P and upregulated after X irradiation in MI surviving cells, demonstrating a more favorable profile after P irradiation. Both irradiation types stimulated vegf-c promoter activity in a NF-κB-dependent transcriptional regulation manner, but at a lesser extent after P, as compared to X irradiation, which correlated with mRNA and protein levels. The cells surviving to MI by P or X generated tumors with higher volume, anarchic architecture and increased density of blood vessels. Increased lymphangiogenesis and a transcriptomic analysis in favor of a more aggressive phenotype were observed in tumors generated with X-irradiated cells. Increased detection of lymphatic vessels in relapsed tumors from patients receiving X radiotherapy was consistent with these findings. This study provides new data about the biological advantage of P, as compared to X irradiation. In addition to its physical advantage in dose deposition, P irradiation may help to improve treatment approaches for HNSCC.

4.
Oral Oncol ; 57: 46-53, 2016 06.
Article in English | MEDLINE | ID: mdl-27208844

ABSTRACT

The "Hallmarks of Cancer" describe the ways by which cancer cells bypass homeostasis. Escape from replicative senescence is one of the earliest features of cancer cells. Maintenance of the telomeres through reactivation of telomerase was initially associated with replicative immortality in various cancers. The shelterin complex, a telomeric hexaprotein association, plays a key role in telomere maintenance and in the hallmarks of cancer. Some shelterin proteins are overexpressed in diverse cancers and can promote tumorigenesis in animal models. Shelterin can also have an impact on tumor size, tumor growth and resistance to treatment. Studies into the expression level of shelterin in oral squamous cell carcinoma (OSCC) report contradictory results. Moreover, the exact role of these proteins in OSCC tumorigenesis remains uncertain. In this review, we examined the data linking telomeres and hallmarks of OSCC. Furthermore, we examined the literature concerning telomeres and the clinical outcome of OSCC. Finally, we propose a model encompassing the role of shelterin proteins in oral tumorigenesis and treatment outcome.


Subject(s)
Carcinogenesis , Carcinoma, Squamous Cell/pathology , Mouth Neoplasms/pathology , Telomerase/metabolism , Telomere-Binding Proteins/metabolism , Animals , Humans , Shelterin Complex , Telomere
5.
Gene Ther ; 22(2): 196-201, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25410741

ABSTRACT

Simian adeno-associated virus (AAV) serotype rh.10 is a promising gene therapy tool, achieving safe, sustained transgene expression in the nervous system, lung, liver and heart in animal models. To date, preexisting immunity in humans has not been confirmed, though exposure is unexpected. We compared the humoral immune response with serotypes AAVrh.10 and AAV9 in mice, and AAVrh.10, AAV9 and AAV2 in 100 healthy humans. Mice, injected-intravenously, raised significantly more anti-AAV9 than anti-AAVrh.10 IgG (immunoglobulins), and sera demonstrated greater neutralizing capacity, correspondingly. Antibody cross-binding studies in mice showed negligible cross-recognition between AAVrh.10, AAV9 and AAV2. In humans, IgG prevalence against the most common human serotype, AAV2, was 72%; AAV9, 47% and AAVrh.10, a surprising, 59%. Yet, neutralizing-antibody seroprevalences were 71% for AAV2, 18% for AAV9 and 21% for AAVrh.10. Thus, most anti-AAV9 and anti-AAVrh.10 IgG were nonneutralizing. Indeed, sera generally neutralized AAV2 more strongly than AAVrh.10. Further, all samples neutralizing AAVrh.10 or AAV9 also neutralized AAV2, suggesting antibody cross-recognition. This contrasts with the results in mice, and highlights the complexity of tailoring gene therapy to minimize the immune response in humans, when multiple-mixed infections during a lifetime evoke a broad repertoire of preexisting antibodies capable of cross reacting with non-human serotypes.


Subject(s)
Antibodies, Viral/blood , Dependovirus/immunology , Genetic Therapy , Animals , Antibodies, Viral/immunology , Cross Reactions , Humans , Male , Mice, Inbred ICR , Protein Binding , Transduction, Genetic
6.
Leukemia ; 29(5): 1163-76, 2015 May.
Article in English | MEDLINE | ID: mdl-25394713

ABSTRACT

Deregulated expression of glycolytic enzymes contributes not only to the increased energy demands of transformed cells but also has non-glycolytic roles in tumors. However, the contribution of these non-glycolytic functions in tumor progression remains poorly defined. Here, we show that elevated expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), but not of other glycolytic enzymes tested, increased aggressiveness and vascularization of non-Hodgkin's lymphoma. Elevated GAPDH expression was found to promote nuclear factor-κB (NF-κB) activation via binding to tumor necrosis factor receptor-associated factor-2 (TRAF2), enhancing the transcription and the activity of hypoxia-inducing factor-1α (HIF-1α). Consistent with this, inactive mutants of GAPDH failed to bind TRAF2, enhance HIF-1 activity or promote lymphomagenesis. Furthermore, elevated expression of gapdh mRNA in biopsies from diffuse large B-cell non-Hodgkin's lymphoma patients correlated with high levels of hif-1α, vegf-a, nfkbia mRNA and CD31 staining. Collectively, these data indicate that deregulated GAPDH expression promotes NF-κB-dependent induction of HIF-1α and has a key role in lymphoma vascularization and aggressiveness.


Subject(s)
Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Neoplastic , Glyceraldehyde 3-Phosphate Dehydrogenase (NADP+)/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Lymphoma, Non-Hodgkin/metabolism , NF-kappa B p50 Subunit/metabolism , Animals , Biopsy , Cell Line, Tumor , Enzyme Inhibitors/chemistry , HeLa Cells , Humans , Lymphoma/metabolism , Mice , Mice, Transgenic , Phenotype , Proto-Oncogene Proteins c-myc/metabolism , TNF Receptor-Associated Factor 2/metabolism , Vascular Endothelial Growth Factor A/metabolism
7.
Neuroscience ; 274: 250-9, 2014 Aug 22.
Article in English | MEDLINE | ID: mdl-24846610

ABSTRACT

Animal models of diabetes do not reach the severity of human diabetic neuropathy but relatively mild neurophysiological deficits and minor morphometric changes. The lack of degenerative neuropathy in diabetic rodent models seems to be a consequence of the shorter length of the axons or the shorter animal life span. Diabetes-induced demyelination needs many weeks or even months before it can be evident by morphometrical analysis. In mice myelination of the peripheral nervous system starts at the prenatal period and it is complete several days after birth. Here we induced experimental diabetes to neonatal mice and we evaluated its effect on the peripheral nerve 4 and 8 weeks after diabetes induction. Neurophysiological values showed a decline in sensory nerve conduction velocity at both time-points. Morphometrical analysis of the tibial nerve demonstrated a decrease in the number of myelinated fibers, fiber size and myelin thickness at both time-points studied. Moreover, aldose reductase and poly(ADP-ribose) polymerase activities were increased even if the amount of the enzyme was not affected. Thus, type 1 diabetes in newborn mice induces early peripheral neuropathy and may be a good model to assay pharmacological or gene therapy strategies to treat diabetic neuropathy.


Subject(s)
Diabetes Mellitus, Experimental/physiopathology , Diabetic Neuropathies/physiopathology , Aldehyde Reductase/metabolism , Animals , Animals, Newborn , Animals, Outbred Strains , Blood Glucose , Body Weight , Diabetes Mellitus, Experimental/pathology , Diabetic Neuropathies/pathology , Foot/innervation , Foot/pathology , Male , Mice , Myelin Sheath/pathology , Myelin Sheath/physiology , Nerve Fibers, Myelinated/pathology , Nerve Fibers, Myelinated/physiology , Neural Conduction/physiology , Poly(ADP-ribose) Polymerases/metabolism , Sciatic Nerve/pathology , Sciatic Nerve/physiopathology , Skin/innervation , Skin/pathology
8.
Oncogene ; 31(13): 1683-94, 2012 Mar 29.
Article in English | MEDLINE | ID: mdl-21909141

ABSTRACT

The anti-VEGF targeted antibody bevacizumab (BVZ) has been approved for treating renal cell carcinomas (RCCs). Although BVZ increases the progression-free survival of patients with metastatic RCC, the effect on overall survival is poor. To gain insight into the limited efficacy of BVZ on overall survival, we analyzed patient samples of RCC for angiogenic factors that may participate in escape from anti-VEGF therapy. Our study shows that the level of vascular endothelial growth factor (VEGF) in tumors was increased compared with normal tissue. The level of interleukin-8/CXCL8, a pro-angiogenic member of the CXCL family of cytokines, was also increased in tumors. These observations gave us a good reason to analyze the combined effects of BVZ and anti-CXCL8 antibodies on tumor growth. Surprisingly, we report that BVZ accelerates the growth of RCC in nude mice with in vivo selection of tumor cells with an increased growth capacity. Downregulation of receptor tyrosine phosphatase-κ, a phosphatase implicated in EGF receptor regulation, may partly explain this phenomenon. Modification of the vascular network and development of lymphatic vessels through VEGF-C production and compensatory production of pro-angiogenic CXCL cytokines were also observed. The apparent normalization of the vascular network prompted us to associate BVZ with the chemotherapeutic agent paclitaxel. While efficient in vitro, paclitaxel did not reverse the anti-VEGF effects in vivo. Anti-CXCL8-targeting antibodies were promising as they decreased intra-tumor VEGF production; decreased the pro-angiogenic CXCL/anti-angiogenic CXCL ratio and did not induce lymphangiogenesis. These observations hold clinical implication as they highlight putative markers implicated in escape from BVZ treatment. They also recommend proceeding with caution in the use of anti-VEGF therapy alone for treatment of RCC.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Antibodies, Monoclonal, Humanized/therapeutic use , Carcinoma, Renal Cell/drug therapy , Interleukin-8/metabolism , Kidney Neoplasms/drug therapy , Animals , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bevacizumab , Carcinoma, Renal Cell/blood supply , Carcinoma, Renal Cell/pathology , Cell Proliferation , Female , Humans , Interleukin-8/immunology , Kidney Neoplasms/blood supply , Kidney Neoplasms/pathology , Mice , Mice, Nude , Neoplasm Transplantation , Paclitaxel/administration & dosage , Paclitaxel/pharmacology , Vascular Endothelial Growth Factor A/antagonists & inhibitors
9.
Int J Cancer ; 130(12): 2771-82, 2012 Jun 15.
Article in English | MEDLINE | ID: mdl-21805474

ABSTRACT

Ursodeoxycholic acid (UDCA) attenuates colon carcinogenesis in humans and in animal models by an unknown mechanism. We investigated UDCA effects on normal intestinal epithelium in vivo and in vitro to identify the potential chemopreventive mechanism. Feeding of mice with 0.4% UDCA reduced cell proliferation to 50% and suppressed several potential proproliferatory genes including insulin receptor substrate 1 (Irs-1). A similar transcriptional response was observed in the rat intestinal cell line IEC-6 which was then used as an in vitro model. UDCA slowed down the proliferation of IEC-6 cells and induced sustained hyperphosphorylation of ERK1/ERK2 kinases which completely inhibited the proproliferatory effects of EGF and IGF-1. The hyperphosphorylation of ERK1 led to a transcriptional suppression of the Irs-1 gene. Both, the hyperphosphorylation of ERK as well as the suppression of Irs-1 were sufficient to inhibit proliferation of IEC-6 cells. ERK1/ERK2 inhibition in vitro or ERK1 elimination in vitro or in vivo abrogated the antiproliferatory effects of UDCA. We show that UDCA inhibits proliferation of nontransformed intestinal epithelial cells by inducing a sustained hyperphosphorylation of ERK1 kinase which slows down the cell cycle and reduces expression of Irs-1 protein. These data extend our understanding of the physiological and potentially chemopreventive effects of UDCA and identify new targets for chemoprevention.


Subject(s)
Cell Proliferation/drug effects , Extracellular Signal-Regulated MAP Kinases/metabolism , Insulin Receptor Substrate Proteins/metabolism , Intestinal Mucosa/cytology , Intestinal Mucosa/drug effects , Ursodeoxycholic Acid/pharmacology , Animals , Cell Cycle/drug effects , Cell Line , Epidermal Growth Factor/metabolism , Extracellular Signal-Regulated MAP Kinases/genetics , Female , Insulin Receptor Substrate Proteins/biosynthesis , Insulin Receptor Substrate Proteins/genetics , Insulin-Like Growth Factor I/metabolism , Intestinal Mucosa/metabolism , MAP Kinase Signaling System/drug effects , Mice , Mice, Inbred C57BL , Mice, Knockout , Phosphorylation , Ursodeoxycholic Acid/metabolism
10.
Gene Ther ; 18(6): 622-30, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21326330

ABSTRACT

Efficient transduction of the peripheral nervous system (PNS) is required for gene therapy of acquired and inherited neuropathies, neuromuscular diseases and for pain treatment. We have characterized the tropism and transduction efficiency of different adeno-associated vectors (AAV) pseudotypes after sciatic nerve injection in the mouse. Among the pseudotypes tested, AAV2/1 transduced both Schwann cells and neurons, AAV2/2 infected only sensory neurons and AAV2/8 preferentially transduced Schwann cells. AAV2/8 expression in the sciatic nerve was detected up to 10 weeks after administration, the latest time point analyzed. The injected mice developed neutralizing antibodies against all AAVs tested; the titers were higher against AAV2/1 than AAV2/2 and were the lowest for AAV2/8, correlating with a higher transgene expression overtime. AAV2/8 coding for ciliary neurotrophic factor (CNTF) led to an upregulation of P0 and PMP22 myelin proteins, four weeks after transduction of injured sciatic nerves. Importantly, CNTF-transduced mice showed a significant increase in both GAP43 expression in sensory neurons, a marker of axonal regeneration, and the compound muscle action potential. These results prove the utility of AAV8 as a gene therapy vector for Schwann cells to treat myelin disorders or to improve nerve regeneration.


Subject(s)
Dependovirus/genetics , Genetic Therapy/methods , Nerve Regeneration/genetics , Animals , Antibodies, Neutralizing/biosynthesis , Cell Line , Ciliary Neurotrophic Factor/metabolism , Dependovirus/immunology , GAP-43 Protein/metabolism , Genetic Vectors , Injections , Mice , Myelin Proteins/metabolism , Peripheral Nerves , Schwann Cells , Sensory Receptor Cells/metabolism , Serotyping , Transduction, Genetic
11.
Diabetologia ; 54(1): 180-9, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20953578

ABSTRACT

AIMS/HYPOTHESIS: Extracellular signal-regulated kinase (ERK) activity is increased in adipose tissue in obesity and type 2 diabetes mellitus and strong evidences suggests that it is implicated in the downregulation of insulin signalling and action in the insulin-resistant state. To determine the role of ERK1 in obesity-associated insulin resistance in vivo, we inactivated Erk1 (also known as Mapk3) in obese leptin-deficient mice (ob/ob). METHODS: Mice of genotype ob/ob-Erk1⁻(/)⁻ were obtained by crossing Erk1⁻(/)⁻ mice with ob/ob mice. Glucose tolerance and insulin sensitivity were studied in 12-week-old mice. Tissue-specific insulin sensitivity, insulin signalling, liver steatosis and adipose tissue inflammation were determined. RESULTS: While ob/ob-Erk1⁻(/)⁻ and ob/ob mice exhibited comparable body weight and adiposity, ob/ob-Erk1⁻(/)⁻ mice did not develop hyperglycaemia and their glucose tolerance was improved. Hyperinsulinaemic-euglycaemic clamp studies demonstrated an increase in whole-body insulin sensitivity in the ob/ob-Erk1⁻(/)⁻ mice associated with an increase in both insulin-stimulated glucose disposal in skeletal muscles and adipose tissue insulin sensitivity. This occurred in parallel with improved insulin signalling in both tissues. The ob/ob-Erk1⁻(/)⁻ mice were also partially protected against hepatic steatosis with a strong reduction in acetyl-CoA carboxylase level. These metabolic improvements were associated with reduced expression of mRNA encoding inflammatory cytokine and T lymphocyte markers in the adipose tissue. CONCLUSIONS/INTERPRETATION: Our results demonstrate that the targeting of ERK1 could partially protect obese mice against insulin resistance and liver steatosis by decreasing adipose tissue inflammation and by increasing muscle glucose uptake. Our results indicate that deregulation of the ERK1 pathway could be an important component in obesity-associated metabolic disorders.


Subject(s)
Insulin Resistance/physiology , Leptin/deficiency , Mitogen-Activated Protein Kinase 3/deficiency , Obesity/physiopathology , Animals , Fatty Liver/genetics , Fatty Liver/metabolism , Fatty Liver/physiopathology , Female , Insulin Resistance/genetics , Leptin/genetics , Male , Mice , Mice, Knockout , Mice, Obese , Mitogen-Activated Protein Kinase 3/genetics , Obesity/genetics
12.
Am J Physiol Cell Physiol ; 299(2): C189-202, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20463170

ABSTRACT

Intracellular signaling by mitogen-activated protein (MAP) kinases (MAPK) is involved in many cellular responses and in the regulation of various physiological and pathological conditions. Tight control of the localization and duration of extracellular-regulated kinase (ERK), c-Jun NH(2)-terminal kinase (JNK), or p38 MAPK activity is thus a fundamental aspect of cell biology. Several members of the dual-specificity phosphatase (DUSPs) family are able to dephosphorylate MAPK isoforms with different specificity, cellular, and tissue localization. Understanding how these phosphatases are themselves regulated during development or in physiological and pathological conditions is therefore fundamental. Over the years, gene deletion and knockdown studies have completed initial in vitro studies and shed a new light on the global and specific roles of DUSPs in vivo. Whereas DUSP1, DUSP2, and DUSP10 appear as crucial players in the regulation of immune responses, other members of the family, like the ERK-specific DUSP6, were shown to play a major role in development. Recent findings on the involvement of DUSPs in cancer progression and resistance will also be discussed.


Subject(s)
Dual-Specificity Phosphatases/physiology , Neoplasms/enzymology , Neoplasms/etiology , Animals , Humans , Isoenzymes/physiology , MAP Kinase Signaling System/physiology , Mitogen-Activated Protein Kinase Phosphatases/physiology
13.
Cell Death Differ ; 17(1): 158-69, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19680261

ABSTRACT

DJ-1 was recently identified as a gene product responsible for a subset of familial Parkinson's disease (PD). The mechanisms by which mutations in DJ-1 alter its function and account for PD-related pathology remained largely unknown. We show that DJ-1 is processed by caspase-6 and that the caspase-6-derived C-terminal fragment of DJ-1 fully accounts for associated p53-dependent cell death. In line with the above data, we show that a recently described early-onset PD-associated mutation (D149A) renders DJ-1 resistant to caspase-6 proteolysis and abolishes its protective phenotype. Unlike the D149A mutation, the L166P mutation that prevents DJ-1 dimerization does not impair its proteolysis by caspase-6 although it also abolishes DJ-1 antiapoptotic function. Therefore, we show here that DJ-1 loss of function could be due to impaired caspase-6 proteolysis and we document the fact that various DJ-1 mutations could lead to PD pathology through distinct molecular mechanisms.


Subject(s)
Caspase 6/metabolism , Intracellular Signaling Peptides and Proteins/genetics , Mutation , Oncogene Proteins/genetics , Parkinson Disease/genetics , Amino Acid Substitution , Animals , Apoptosis , Brain/metabolism , Cells, Cultured , Dimerization , Down-Regulation , Humans , Intracellular Signaling Peptides and Proteins/metabolism , Mice , Mutagenesis, Site-Directed , Oncogene Proteins/metabolism , Parkinson Disease/metabolism , Protein Deglycase DJ-1 , Tumor Suppressor Protein p53/metabolism
14.
Acta Physiol (Oxf) ; 196(2): 259-65, 2009 Jun.
Article in English | MEDLINE | ID: mdl-18983460

ABSTRACT

AIM: To analyse the correlation between production of angiogenic [vascular endothelial growth factor A (VEGF-A) and interleukin 8 (IL-8)] and lymphangiogenic factors (VEGF-C and D) and adaptation to high altitude (>8000 m). Erythropoietin (EPO) served as a positive control. METHODS: We analysed the percentage of oxygen saturation and the plasmatic contents of VEGF-A, C, D, IL-8 and EPO in seven mountaineers and four Sherpas during an expedition to Mount Everest. Acute mountain sickness was also evaluated using the Lake Louise score. RESULTS: Whereas VEGF-A, IL-8, VEGF-C and EPO were transiently up-regulated at 5000 m and decreased at the highest altitudes, VEGF-D remained elevated throughout the ascent. Sherpas had increased basal levels of VEGF-A, C, IL-8 and EPO and up-regulation of all the tested factors when they passed the altitude at which they lived. CONCLUSION: Our data suggest that expression of angiogenic and lymphangiogenic factors is up-regulated directly or indirectly by altitude-dependent hypoxia. Both factors could be involved in a mechanism of adaptation to high altitudes.


Subject(s)
Acclimatization/physiology , Altitude , Angiogenic Proteins/blood , Mountaineering , Adult , Altitude Sickness/diagnosis , Erythropoietin/blood , Female , Humans , Hypoxia/blood , Interleukin-8/blood , Lymphangiogenesis/physiology , Middle Aged , Neovascularization, Physiologic/physiology , Oxygen/blood , Vascular Endothelial Growth Factor A/blood , Vascular Endothelial Growth Factor C/blood , Vascular Endothelial Growth Factor D/blood
15.
Oncogene ; 27(26): 3685-91, 2008 Jun 12.
Article in English | MEDLINE | ID: mdl-18223677

ABSTRACT

MAP kinases phosphatases (MKPs) belong to the dual-specificity phosphatase family (DUSP) and dephosphorylate phosphothreonine and phosphotyrosine within MAP kinases. We had previously shown that DUSP6/MKP-3 was phosphorylated and degraded upon growth factor stimulation, in a MEK-dependent manner. Here we show that another pathway involved in growth factor signaling, the PI3K/mTOR signaling pathway, accounts for a part of the phosphorylation and degradation of DUSP6 induced by serum growth factors, as evidenced by experiments using pharmacological inhibitors of PI3 kinase and mammalian target of rapamycin (mTOR). Moreover, specific agonists of the mTOR pathway, such as amino acids or insulin/IGF-1, which do not activate extracellular signal regulated kinases (ERKs) in our cellular model, were also able to induce the phosphorylation and degradation of DUSP6. However, a basal activity of MEK was required for the mTOR pathway-mediated phosphorylation to occur. Mutagenesis studies identified serine 159 within DUSP6 as the target of the mTOR pathway. The ERK phosphatase DUSP6 may thus constitute a novel branch-point of the crosstalk between two major signaling pathways induced by growth factors, the MEK/ERK pathway and the PI3K/mTOR pathway.


Subject(s)
Dual Specificity Phosphatase 6/metabolism , Protein Kinases/physiology , Protein Processing, Post-Translational , Signal Transduction/physiology , Animals , Cells, Cultured , Cricetinae , Insulin-Like Growth Factor I/pharmacology , Phosphatidylinositol 3-Kinases/physiology , Phosphorylation , TOR Serine-Threonine Kinases
16.
Ann Oncol ; 18(8): 1335-41, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17693647

ABSTRACT

BACKGROUND: To examine the impact of a frequent her2 gene polymorphism (Ile655Val) on tumor growth and on the pharmacodynamics of treatment by trastuzumab. PATIENTS AND METHODS: Experimental study: The growth characteristics of cells expressing the Ile or Val isoform were examined in vitro and after injection into nude mice. The effect of trastuzumab was determined in both experimental models. Clinical study: 61 patients with advanced breast cancers and treated by trastuzumab were genotyped for HER2 by PCR-RFLP. The influence of HER2 genotype on the trastuzumab treatment was examined. RESULTS: Experimental study: HER2-expressing cells acquired the characteristics of tumor cells. The Val isoform-expressing cells showed the highest growth capacity and developed aggressive tumors sensitive to trastuzumab. Clinical study: There was no link between tumor response or survival and HER2 genotype. All cases of treatment-related cardiotoxicity were found in the Ile/Val group and there was no cardiac toxicity in the Val/Val and Ile/Ile patients. CONCLUSIONS: This study establishes a clear-cut difference between the two HER2 isoforms regarding their tumorogenic potential with an advantage for the Val/HER2 isoform. In breast cancer patients treated with trastuzumab, the presence of a Val allele may constitute a risk factor for cardiac toxicity.


Subject(s)
Antibodies, Monoclonal/adverse effects , Antineoplastic Agents/adverse effects , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Heart/drug effects , Receptor, ErbB-2/genetics , Adult , Aged , Aged, 80 and over , Animals , Antibodies, Monoclonal, Humanized , Base Sequence , Blotting, Western , Breast Neoplasms/pathology , Cell Transformation, Neoplastic/genetics , Female , Heart Diseases/chemically induced , Humans , Immunohistochemistry , Mice , Mice, Nude , Middle Aged , Molecular Sequence Data , Mutagenesis, Site-Directed , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/genetics , Neoplasms, Experimental/pathology , Polymerase Chain Reaction , Polymorphism, Genetic , Polymorphism, Restriction Fragment Length , Protein Isoforms/genetics , Transfection , Trastuzumab
17.
Oncogene ; 25(53): 7096-105, 2006 Nov 09.
Article in English | MEDLINE | ID: mdl-16715126

ABSTRACT

Transcription factor Sp1 has recently been shown to be overexpressed in a number of human cancers and its overexpression contributes to malignant transformation. Sp1 regulates the expression of a number of genes participating in multiple aspects of tumorigenesis such as angiogenesis, cell growth and apoptosis resistance. To better understand the role of increased Sp1 levels on apoptosis regulation we have used retroviruses to overexpress this protein in haematopoietic Baf-3 cells and in 3T3 fibroblasts. We have also used inducible expression systems to control ectopic Sp1 levels in different cell types. Surprisingly, Sp1 overexpression on its own induces apoptosis in all the cellular models tested. The apoptotic pathways induced by Sp1 overexpression are cell type specific. Finally, using a truncated form of Sp1, we show that Sp1-induced apoptosis requires its DNA-binding domain. Our results highlight that Sp1 levels in untransformed cells must be tightly regulated as Sp1 overexpression leads to the induction of apoptosis. Our results also suggest that cancer cells overexpressing Sp1 can avoid Sp1-induced apoptosis.


Subject(s)
Apoptosis , Sp1 Transcription Factor/metabolism , Animals , DNA , Gene Expression , Humans , Mice , Sp1 Transcription Factor/genetics
18.
Br J Cancer ; 94(10): 1516-23, 2006 May 22.
Article in English | MEDLINE | ID: mdl-16641910

ABSTRACT

Vascular endothelial growth factor-A (VEGF-A) has been demonstrated to play an important role in tumour angiogenesis and to influence prognosis in many cancers. However its prognostic value in head and neck squamous cell carcinomas (HNSCCs) remains controversial. Therefore, we investigated the clinical relevance of VEGF-A expression in HNSCCs and analysed whether its expression was associated with PAIP2 protein levels, a VEGF-A mRNA-binding partner that strongly regulates VEGF-A expression in tissue culture. We determined the correlation of VEGF-A and PAIP2 protein levels, quantitatively evaluated in tumour tissue homogenates from 54 patients with HNSCC, to clinicopathological parameters. We showed that VEGF-A expression in HNSCC is correlated to the stage of tumour differentiation (P=0.050) and is an independent prognostic factor for progression-free survival (P=0.001) and overall survival (P=0.0004). In a pharynx carcinoma cell line, we demonstrated by RNA interference that VEGF-A expression is closely controlled by PAIP2. Moreover, in human HNSCCs, VEGF-A expression is significantly correlated to PAIP2 protein levels (P=0.0018). Nevertheless, PAIP2 expression is associated with neither clinicopathological factors nor patient's survival. Our data suggest that, in contrast to PAIP2 protein levels, which are unrelated to tumour prognosis, VEGF-A expression could serve as a prognostic marker in head and neck cancer and may be helpful for targeted therapies.


Subject(s)
Head and Neck Neoplasms/metabolism , RNA-Binding Proteins/metabolism , Repressor Proteins/metabolism , Vascular Endothelial Growth Factor A/metabolism , Adult , Aged , Aged, 80 and over , Blotting, Northern , Blotting, Western , Cell Differentiation , Female , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/pathology , Humans , Laryngeal Neoplasms , Male , Middle Aged , Prognosis , RNA, Small Interfering/pharmacology , RNA-Binding Proteins/genetics , Repressor Proteins/genetics , Retrospective Studies , Survival Rate , Tumor Cells, Cultured , Vascular Endothelial Growth Factor A/genetics
19.
An. psiquiatr ; 20(6): 262-265, jun. 2004. tab
Article in Es | IBECS | ID: ibc-35526

ABSTRACT

Los profesionales que trabajamos con familias de esquizofrénicos encontramos con frecuencia las relaciones familiares alteradas. Estaríamos de acuerdo en que la mayoría de los síntomas se desarrollan a partir de alteraciones vividas en las relaciones familiares. Objetivos: Determinar si las pautas de crianza dentro del vínculo parental intervienen en la esquizofrenia y predecir en función de las puntuaciones una mayor recaída de la enfermedad. Metodología: Se seleccionaron 40 pacientes entre hombres y mujeres de 20 a 40 años que residen en la comarca del Segria (Lleida) y que están diagnosticados de esquizofrenia según el DSM IV. Se comparó con una muestra control de 34 personas que no estaban diagnosticadas de trastornos mentales. El material utilizado ha sido una entrevista sociodemográfica y clínica y el PBI. Resultados y conclusiones: El grupo patológico que había hecho reingresos presentaban puntuaciones altas en sobreprotección y bajas en cuidados. Aparece una predominancia de alto cuidado y baja sobreprotección en el grupo control y de bajo cuidado y alta sobreprotección en el grupo patológico (AU)


Subject(s)
Adult , Female , Male , Humans , Schizophrenia/diagnosis , Schizophrenia/rehabilitation , Schizophrenic Psychology , Breeding/methods , Professional-Family Relations , Control Groups , Interview, Psychological/methods , Interviews as Topic/methods , Father-Child Relations , Parent-Child Relations , Behavior Therapy/methods , Behavior Therapy/organization & administration , Family/psychology , Demography , Paternal Behavior , Perception/physiology , Perceptual Disorders/psychology , Surveys and Questionnaires
20.
Matronas prof ; 3(10): 10-12, dic. 2002. ilus
Article in Es | IBECS | ID: ibc-23038

ABSTRACT

Se presenta un programa educativo para la promoción de la lactancia materna, en formato CD-ROM, para que pueda ser utilizado tanto por los profesionales de la salud, en sus labores educativas, como por los propios usuarios (mujer y/o pareja). El programa también incluye un cuestionario de conocimientos que posibilita el feedback y ofrece direcciones de asociaciones de autoayuda y páginas web de interés (AU)


Subject(s)
Female , Male , Humans , Breast Feeding , Health Education , Computer-Assisted Instruction , CD-ROM
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