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1.
Rev Neurol (Paris) ; 178(4): 326-336, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34657733

RESUMO

BACKGROUND: Cognitive impairment is frequent and disabling in multiple sclerosis (MS). The Brief International Cognitive Assessment in MS (BICAMS) is a recent short battery usable in clinical practice for cognitive evaluation of MS patients. OBJECTIVE: To find cortical areas or brain volumes on magnetic resonance imaging (MRI) structural sequences associated with BICAMS scores in MS. METHODS: In this cross-sectional single-center study (NCT03656055, September 4, 2018), 96 relapsing remitting-MS patients under natalizumab and without recent clinical or radiological inflammation were included. Patients underwent brain MRI and the three BICAMS tests, evaluating information processing speed (SDMT), visuo-spatial memory (BVMT-R), and verbal memory (FVLT). RESULTS: Cortical thickness in the left frontal superior and the right precentral gyri was associated with BVMT-R scores whereas cortical thickness in the left Broca's area and the right superior temporal gyrus was associated with FVLT scores. We observed associations between white matter inflammatory lesions connected to these cortical regions and BICAMS subscores. CONCLUSIONS: BICAMS scores are associated with specific cortical areas, the cognitive domain matching the known functions of the cortical area. Specific cognitive impairments in MS may be associated with specific cortical regions, themselves influenced by white matter inflammatory lesions and demographical parameters (age, sex, education level).


Assuntos
Disfunção Cognitiva , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Cognição , Disfunção Cognitiva/complicações , Estudos Transversais , Humanos , Esclerose Múltipla/complicações , Esclerose Múltipla Recidivante-Remitente/complicações , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Testes Neuropsicológicos
2.
Haemophilia ; 24(1): 77-84, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29082639

RESUMO

INTRODUCTION: Joint arthropathy is the long-term consequence of joint bleeding in people with severe haemophilia. AIM: This study assessed change in joint health over time in subjects receiving recombinant factor VIII Fc fusion protein (rFVIIIFc) prophylaxis. METHODS: ALONG is the phase 3 pivotal study in which the benefit of rFVIIIFc as a prophylactic treatment for bleeding control was shown in previously treated severe haemophilia patients ≥12 years of age (arm 1: 25-65 IU/kg every 3-5 days, arm 2: 65 IU/kg weekly and arm 3: episodic). After completing ALONG, subjects had the option to enrol into the extension study (ASPIRE). This interim, post hoc analysis assessed changes in joint health over ~2.8 years in these patients. RESULTS: Forty-seven subjects had modified Haemophilia Joint Health Score (mHJHS) data at A-LONG baseline, ASPIRE baseline and ASPIRE Year 1 and Year 2. Compared with A-LONG baseline (23.4), mean improvement at ASPIRE Year 2 was -4.1 (95% confidence interval [CI], -6.5, -1.8; P = .001). Regardless of prestudy treatment regimen, subjects showed continuous improvement in mHJHS from A-LONG baseline through ASPIRE Year 2 (prestudy prophylaxis: -2.4, P = .09; prestudy episodic treatment: -7.2, P = .003). Benefits were seen in subjects with target joints (-5.6, P = .005) as well as those with severe arthropathy (-8.8, P = .02). The mHJHS components with the greatest improvement at ASPIRE Year 2 were swelling (-1.4, P = .008), range of motion (-1.1, P = .03) and strength (-0.8, P = .04). CONCLUSIONS: Prophylaxis with rFVIIIFc may improve joint health over time regardless of prestudy prophylaxis or episodic treatment regimens.


Assuntos
Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Articulações/fisiopatologia , Proteínas Recombinantes de Fusão/uso terapêutico , Adolescente , Adulto , Relação Dose-Resposta a Droga , Esquema de Medicação , Hemofilia A/complicações , Hemofilia A/patologia , Humanos , Artropatias/complicações , Artropatias/diagnóstico , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Índice de Gravidade de Doença , Adulto Jovem
3.
Haemophilia ; 24(2): 245-252, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29436077

RESUMO

INTRODUCTION: Immune tolerance induction (ITI) is the gold standard for eradication of factor VIII inhibitors in severe haemophilia A; however, it usually requires treatment for extended periods with associated high burden on patients and healthcare resources. AIM: Review outcomes of ITI with recombinant factor VIII Fc fusion protein (rFVIIIFc) in patients with severe haemophilia A and high-titre inhibitors. METHODS: Multicentre retrospective chart review of severe haemophilia A patients treated with rFVIIIFc for ITI. RESULTS: Of 19 patients, 7 were first-time ITI and 12 were rescue ITI. Of 7 first-time patients, 6 had at least 1 high-risk feature for ITI failure. Four of 7 first-time patients were tolerized in a median of 7.8 months. The remaining 3 patients continue on rFVIIIFc ITI. Of 12 rescue patients, 7 initially achieved a negative Bethesda titre (≤0.6) in a median of 3.3 months, 1 had a decrease in Bethesda titre and continues on rFVIIIFc ITI and 4 have not demonstrated a decrease in Bethesda titre. Of these 4, 3 continue on rFVIIIFc ITI and 1 switched to bypass therapy alone. Two initially responsive patients transitioned to other factors due to recurrence. Overall, 16 of 19 patients remain on rFVIIIFc (prophylaxis or ITI). For those still undergoing ITI, longer follow-up is needed to determine final outcomes. No adverse events reported. CONCLUSIONS: Recombinant factor VIII Fc fusion protein demonstrated rapid time to tolerization in high-risk first-time ITI patients. For rescue ITI, rFVIIIFc showed therapeutic benefit in some patients who previously failed ITI with other products. These findings highlight the need to further evaluate the use of rFVIIIFc for ITI.


Assuntos
Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Proteínas Recombinantes de Fusão/uso terapêutico , Criança , Pré-Escolar , Fator VIII/farmacologia , Humanos , Fragmentos Fc das Imunoglobulinas/farmacologia , Lactente , Proteínas Recombinantes de Fusão/farmacologia , Estudos Retrospectivos
4.
Int J Obes (Lond) ; 40(11): 1794-1801, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27377952

RESUMO

BACKGROUND: Socio-economic status (SES) is a strong determinant of eating behavior and the obesity risk. OBJECTIVE: To determine which eating and lifestyle behaviors mediate the association between SES and obesity. METHODS: We performed a case-control study of 318 obese people and 371 non-obese people in northern France. Ten eating behavior traits were assessed using the Three-Factor Eating Questionnaire Revised 21-Item and an eating attitude questionnaire (on plate size, the number of servings, reasons for stopping eating and the frequency of eating standing up, eating in front of the television set (TV) and eating at night). The SES score (in three categories) was based on occupation, education and income categories. Mediation analysis was performed using the test of joint significance and the difference of coefficients test. RESULTS: The age- and gender-adjusted obesity risk was higher for individuals in the low-SES groups (odds ratio (OR) (95% confidence interval (CI)=1.82 (1.48-2.24), P<0.0001). Additional servings were associated with a higher obesity risk (OR=3.43, P<0.0001). Cognitive restraint (P<0.0001) and emotional eating (P<0.0001) scores were higher in obese participants than in non-obese participants but did not depend on SES. Of the 10 potential factors tested, eating off a large plate (P=0.01), eating at night (P=0.04) and uncontrolled eating (P=0.03) significantly mediated the relationship between SES and obesity. CONCLUSION: Our results highlighted a number of obesogenic behaviors among socially disadvantaged participants: large plate size, uncontrolled eating and eating at night were significant mediators of the relationship between SES and the obesity risk.


Assuntos
Comportamento Alimentar , Renda/estatística & dados numéricos , Obesidade/economia , Obesidade/psicologia , Adulto , Estudos de Casos e Controles , Escolaridade , Feminino , França/epidemiologia , Inquéritos Epidemiológicos , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Ocupações/estatística & dados numéricos , Razão de Chances , Tamanho da Porção/estatística & dados numéricos , Classe Social , Inquéritos e Questionários , Televisão
5.
Am J Physiol Cell Physiol ; 307(12): C1102-12, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25298423

RESUMO

Iodide is captured by thyrocytes through the Na(+)/I(-) symporter (NIS) before being released into the follicular lumen, where it is oxidized and incorporated into thyroglobulin for the production of thyroid hormones. Several reports point to pendrin as a candidate protein for iodide export from thyroid cells into the follicular lumen. Here, we show that a recently discovered Ca(2+)-activated anion channel, TMEM16A or anoctamin-1 (ANO1), also exports iodide from rat thyroid cell lines and from HEK 293T cells expressing human NIS and ANO1. The Ano1 mRNA is expressed in PCCl3 and FRTL-5 rat thyroid cell lines, and this expression is stimulated by thyrotropin (TSH) in rat in vivo, leading to the accumulation of the ANO1 protein at the apical membrane of thyroid follicles. Moreover, ANO1 properties, i.e., activation by intracellular calcium (i.e., by ionomycin or by ATP), low but positive affinity for pertechnetate, and nonrequirement for chloride, better fit with the iodide release characteristics of PCCl3 and FRTL-5 rat thyroid cell lines than the dissimilar properties of pendrin. Most importantly, iodide release by PCCl3 and FRTL-5 cells is efficiently blocked by T16Ainh-A01, an ANO1-specific inhibitor, and upon ANO1 knockdown by RNA interference. Finally, we show that the T16Ainh-A01 inhibitor efficiently blocks ATP-induced iodide efflux from in vitro-cultured human thyrocytes. In conclusion, our data strongly suggest that ANO1 is responsible for most of the iodide efflux across the apical membrane of thyroid cells.


Assuntos
Polaridade Celular , Canais de Cloreto/metabolismo , Iodetos/metabolismo , Proteínas de Neoplasias/metabolismo , Glândula Tireoide/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Anoctamina-1 , Transporte Biológico , Cálcio/metabolismo , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/genética , Células HEK293 , Humanos , Moduladores de Transporte de Membrana/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Interferência de RNA , Ratos , Glândula Tireoide/citologia , Glândula Tireoide/efeitos dos fármacos , Tireotropina/metabolismo , Fatores de Tempo , Transfecção
6.
Cancer Metastasis Rev ; 32(3-4): 403-21, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23615877

RESUMO

Our knowledge of the biology of solid cancer has greatly progressed during the last few years, and many excellent reviews dealing with the various aspects of this biology have appeared. In the present review, we attempt to bring together these subjects in a general systems biology narrative. It starts from the roles of what we term entropy of signaling and noise in the initial oncogenic events, to the first major transition of tumorigenesis: the independence of the tumor cell and the switch in its physiology, i.e., from subservience to the organism to its own independent Darwinian evolution. The development after independence involves a constant dynamic reprogramming of the cells and the emergence of a sort of collective intelligence leading to invasion and metastasis and seldom to the ultimate acquisition of immortality through inter-individual infection. At each step, the probability of success is minimal to infinitesimal, but the number of cells possibly involved and the time scale account for the relatively high occurrence of tumorigenesis and metastasis in multicellular organisms.


Assuntos
Neoplasias/etiologia , Neoplasias/patologia , Biologia de Sistemas , Animais , Transformação Celular Neoplásica , Humanos , Metástase Neoplásica
7.
Haemophilia ; 20(4): e327-35, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24811361

RESUMO

Recombinant factor IX Fc (rFIXFc) fusion protein is the first of a new class of bioengineered long-acting factors approved for the treatment and prevention of bleeding episodes in haemophilia B. The aim of this work was to describe the manufacturing process for rFIXFc, to assess product quality and to evaluate the capacity of the process to remove impurities and viruses. This manufacturing process utilized a transferable and scalable platform approach established for therapeutic antibody manufacturing and adapted for production of the rFIXFc molecule. rFIXFc was produced using a process free of human- and animal-derived raw materials and a host cell line derived from human embryonic kidney (HEK) 293H cells. The process employed multi-step purification and viral clearance processing, including use of a protein A affinity capture chromatography step, which binds to the Fc portion of the rFIXFc molecule with high affinity and specificity, and a 15 nm pore size virus removal nanofilter. Process validation studies were performed to evaluate identity, purity, activity and safety. The manufacturing process produced rFIXFc with consistent product quality and high purity. Impurity clearance validation studies demonstrated robust and reproducible removal of process-related impurities and adventitious viruses. The rFIXFc manufacturing process produces a highly pure product, free of non-human glycan structures. Validation studies demonstrate that this product is produced with consistent quality and purity. In addition, the scalability and transferability of this process are key attributes to ensure consistent and continuous supply of rFIXFc.


Assuntos
Fator IX/genética , Fragmentos Fc das Imunoglobulinas/genética , Engenharia de Proteínas/métodos , Proteínas Recombinantes de Fusão/genética , Células HEK293 , Humanos , Segurança , Vírus/isolamento & purificação
8.
Cancer Radiother ; 28(2): 174-181, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38182482

RESUMO

PURPOSE: Thymoma is a rare tumour. The most common treatment for thymoma is surgical resection, while the use of radiotherapy and chemotherapy remains controversial. PATIENTS AND METHODS: We conducted a monocentric observational study of 31 patients diagnosed with thymoma from June 2004 to July 2020 at cancer centre in Strasbourg, France. We analysed the outcomes of the patients. RESULTS: The 2- and 5- year locoregional relapse-free survival rates were 96.3% (95% confidence interval [CI]: 76.5-99.5%) and 68.0% (95% CI: 43.8-83.5%), respectively. Radiotherapy and chemotherapy significantly improved local tumour control (P=0.0008 and 0.04, respectively), while a larger initial tumour size significantly worsened local control rates (P=0.04). The 5- and 10-year overall survival rates were 87.1% (95% CI: 69.2-95%) and 81.7% (95% CI: 60.3-92.2%), respectively. The median overall survival was not reached, and no favourable factor was retrieved. For relapsed patients, the median overall survival after relapse was 115 months. CONCLUSION: Despite the inherent limitations of retrospective studies with a limited patient sample size, we demonstrated that chemotherapy and radiotherapy in addition to surgery were effective in achieving local control and contributed to improving patient outcomes in thymoma. Notably, an aggressive treatment strategy at the time of relapse resulted in favourable outcomes for retreated patients.


Assuntos
Timoma , Neoplasias do Timo , Humanos , Timoma/radioterapia , Radioterapia Adjuvante , Estudos Retrospectivos , Recidiva Local de Neoplasia/patologia , Neoplasias do Timo/terapia , Neoplasias do Timo/patologia , Recidiva , Quimioterapia Adjuvante , Estadiamento de Neoplasias , Intervalo Livre de Doença
9.
Int J Obes (Lond) ; 37(5): 666-72, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22828941

RESUMO

BACKGROUND: REV-ERBα has been shown to regulate adipogenesis and lipid metabolism as well as to link the circadian timing system to whole body metabolic homeostasis. We thus tested whether polymorphisms in REV-ERBα could be associated with metabolic phenotypes in human population samples. METHODS: We analyzed the associations between 5 REV-ERBα polymorphisms and anthropometric (body weight, body mass index (BMI), waist and hip circumferences), biochemical (plasma lipid, glucose and insulin levels) and clinical (systolic and diastolic blood pressure) variables in three population-based studies (MONICA Lille n=1155 adults, MONA LISA Lille n=1170 adults and HELENA n=1155 adolescents). We assessed in vitro, the potential influence of one REV-ERBα polymorphism in transient transfection assays using two different cell lines. RESULTS: We observed significant and consistent associations between the T minor allele of the REV-ERBα rs2071427 polymorphism (located in intron 1) and higher BMI (mean allele effect=+0.33 kg m(-2)) in the MONICA Lille (P=0.02), MONA LISA (P=0.02) and HELENA (P=0.03) studies. The odds ratios for obesity associated with this allele were 1.67 (1.00-2.79) (P=0.05) in MONICA Lille, 1.29 (1.01-1.65) (P=0.04) in MONA LISA Lille and the odds ratio for overweight was 1.48 (1.08-2.03) (P=0.01) in HELENA. In transfection experiments in human hepatocyte-derived cell lines, the REV-ERBα intron 1 directed the transcription of a luciferase reporter gene independently of the rs2071427 polymorphism. CONCLUSION: Our results suggest that the REV-ERBα rs2071427 polymorphism modulates body fat mass in both adult and young people.


Assuntos
Regulação da Expressão Gênica , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/genética , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Antropometria , Glicemia/metabolismo , Índice de Massa Corporal , Criança , Ritmo Circadiano , Europa (Continente)/epidemiologia , Feminino , Redes Reguladoras de Genes , Humanos , Insulina/sangue , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/metabolismo , Obesidade/epidemiologia , Obesidade/metabolismo , Razão de Chances , Fenótipo
10.
Nat Genet ; 7(3): 396-401, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7920658

RESUMO

The thyrotropin receptor (TSHR), a member of the large family of G protein-coupled receptors, controls both the function and growth of thyroid cells via stimulation of adenylyl cyclase. We report two different mutations in the TSHR gene of affected members of two large pedigrees with non-autoimmune autosomal dominant hyperthyroidism (toxic thyroid hyperplasia), that involve residues in the third (Val509Ala) and seventh (Cys672Tyr) transmembrane segments. When expressed by transfection in COS-7 cells, the mutated receptors display a higher constitutive activation of adenylyl cyclase than wild type. This new disease entity is the germline counterpart of hyperfunctioning thyroid adenomas, in which different somatic mutations with similar functional characteristics have been demonstrated.


Assuntos
Genes Dominantes , Hipertireoidismo/genética , Mutação Puntual , Receptores da Tireotropina/genética , Adenoma/genética , Adenilil Ciclases/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Chlorocebus aethiops , AMP Cíclico/fisiologia , Análise Mutacional de DNA , Ativação Enzimática , Feminino , França/epidemiologia , Humanos , Masculino , Modelos Moleculares , Dados de Sequência Molecular , Linhagem , Conformação Proteica , Receptores da Tireotropina/química , Receptores da Tireotropina/fisiologia , Sistemas do Segundo Mensageiro , Neoplasias da Glândula Tireoide/genética , Transfecção
11.
Rev Med Liege ; 68(5-6): 252-5, 2013.
Artigo em Francês | MEDLINE | ID: mdl-23888573

RESUMO

WHO, for the first time in its history, asked in 2003, all Member States to sign and enforce a Framework Convention on Tobacco Control (FCTC). Ten years later, it seems important to describe the achievements made in Belgium. The main legislative measures that are taken to control the major avoidable risk factor for health, are recalled. The present status of Belgium activity in this field is described, with an emphasis on the role of health professionals to help smokers quit. The difficult challenge of curing chronic tobacco dependence disease is underlined. Regarding the fight to render tobacco products less attractive, some breakthroughs are occurring in specific countries, and some are maybe coming soon in Europe.


Assuntos
Prevenção do Hábito de Fumar , Fumar/legislação & jurisprudência , Bélgica , Humanos , Saúde Pública , Abandono do Hábito de Fumar
12.
Br J Cancer ; 107(6): 994-1000, 2012 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-22828612

RESUMO

BACKGROUND: Papillary thyroid cancer (PTC) incidence increased dramatically in children after the Chernobyl accident, providing a unique opportunity to investigate the molecular features of radiation-induced thyroid cancer. In contrast to the previous studies that included age-related confounding factors, we investigated mRNA expression in PTC and in the normal contralateral tissues of patients exposed and non-exposed to the Chernobyl fallout, using age- and ethnicity-matched non-irradiated cohorts. METHODS: Forty-five patients were analysed by full-genome mRNA microarrays. Twenty-two patients have been exposed to the Chernobyl fallout; 23 others were age-matched and resident in the same regions of Ukraine, but were born after 1 March 1987, that is, were not exposed to ¹³¹I. RESULTS: A gene expression signature of 793 probes corresponding to 403 genes that permitted differentiation between normal tissues from patients exposed and from those who were not exposed to radiation was identified. The differences were confirmed by quantitative RT-PCR. Many deregulated pathways in the exposed normal tissues are related to cell proliferation. CONCLUSION: Our results suggest that a higher proliferation rate in normal thyroid could be related to radiation-induced cancer either as a predisposition or as a consequence of radiation. The signature allows the identification of radiation-induced thyroid cancers.


Assuntos
Biomarcadores Tumorais/análise , Acidente Nuclear de Chernobyl , Perfilação da Expressão Gênica , Neoplasias Induzidas por Radiação/química , Glândula Tireoide/química , Neoplasias da Glândula Tireoide/química , Adolescente , Carcinoma , Carcinoma Papilar , Criança , Pré-Escolar , Diagnóstico Diferencial , Dieta , Suscetibilidade a Doenças , Humanos , Lactente , Iodo/administração & dosagem , Iodo/deficiência , Neoplasias Induzidas por Radiação/diagnóstico , Neoplasias Induzidas por Radiação/epidemiologia , Neoplasias Induzidas por Radiação/genética , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Câncer Papilífero da Tireoide , Glândula Tireoide/efeitos da radiação , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/etiologia , Neoplasias da Glândula Tireoide/genética , Tireotropina/metabolismo , Transcriptoma , Ucrânia/epidemiologia , Adulto Jovem
13.
Sci Rep ; 11(1): 18144, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34518581

RESUMO

The specificity of dairy Protected Designation of Origin (PDO) products is related to their "terroir" of production. This relationship needs better understanding for efficient and sustainable productions preserving the agroecological equilibrium of agroecosystems, especially grasslands. Specificity of PDO Comté cheese was related to the diversity of natural raw milk bacterial communities, but their sources need to be determined. It is hypothesized that raw milk indigenous microbial communities may originate from permanent grazed grasslands by the intermediate of dairy cows according to the sequence soil-phyllosphere-teat-milk. This hypothesis was evaluated on a 44 dairy farms network across PDO Comté cheese area by characterizing prokaryotic and fungal communities of these compartments by metabarcoding analysis (16S rRNA gene: V3-V4 region, 18S rRNA gene: V7-V8 region). Strong and significant links were highlighted between the four compartments through a network analysis (0.34 < r < 0.58), and were modulated by soil pH, plant diversity and elevation; but also by farming practices: organic fertilization levels, cattle intensity and cow-teat care. This causal relationship suggests that microbial diversity of agroecosystems is a key player in relating a PDO product to its "terroir"; this under the dependency of farming practices. Altogether, this makes the "terroir" even more local and needs to be considered for production sustainability.

14.
Carcinogenesis ; 31(2): 149-58, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19858069

RESUMO

The concept of cancer stem cells (CSC) embodies two aspects: the stem cell as the initial target of the oncogenic process and the existence of two populations of cells in cancers: the CSC and derived cells. The second is discussed in this review. CSC are defined as cells having three properties: a selectively endowed tumorigenic capacity, an ability to recreate the full repertoire of cancer cells of the parent tumor and the expression of a distinctive repertoire of surface biomarkers. In operational terms, the CSC are among all cancer cells those able to initiate a xenotransplant. Other explicit or implicit assumptions exist, including the concept of CSC as a single unique infrequent population of cells. To avoid such assumptions, we propose to use the operational term tumor-propagating cells (TPC); indeed, the cells that initiate transplants did not initiate the cancer. The experimental evidence supporting the explicit definition is analyzed. Cancers indeed contain a fraction of cells mainly responsible for the tumor development. However, there is evidence that these cells do not represent one homogenous population. Moreover, there is no evidence that the derived cells result from an asymmetric, qualitative and irreversible process. A more general model is proposed of which the CSC model could be one extreme case. We propose that the TPC are multiple evolutionary selected cancer cells with the most competitive properties [maintained by (epi-)genetic mechanisms], at least partially reversible, quantitative rather than qualitative and resulting from a stochastic rather than deterministic process.


Assuntos
Neoplasias/patologia , Células-Tronco Neoplásicas/patologia , Humanos
15.
Biochim Biophys Acta ; 1795(2): 92-103, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19167460

RESUMO

Established human cancer cell lines are routinely used as experimental models for human cancers. Their validity for such use is analyzed and discussed, with particular focus on thyroid tumors. Although cell lines retain some properties of the cells of origin, from the points of view of their genetics, epigenetics and gene expression, they show clear differences in these properties compared to in vivo tumors. This can be explained by a prior selection of initiating cells and a Darwinian evolution in vitro. The properties of the cell lines are compared to those of the postulated cancer stem cells and their use as models in this regard are discussed. Furthermore, other proper and possible uses of the cell lines are discussed.


Assuntos
Linhagem Celular Tumoral , Células-Tronco Neoplásicas , Evolução Biológica , Linhagem Celular Tumoral/efeitos dos fármacos , Humanos , Células-Tronco Neoplásicas/efeitos dos fármacos , Oncogenes , Fenótipo
16.
Mol Psychiatry ; 14(1): 106-16, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17893704

RESUMO

To more rapidly identify candidate genes located within chromosomal regions of interest defined by genome scan studies in Alzheimer's disease (AD), we have developed a customized microarray containing all the ORFs (n=2741) located within nine of these regions. Levels of gene expression were assessed in total RNA from brain tissue of 12 controls and 12 AD patients. Of all genes showing differential expression, we focused on the ornithine transcarbamylase (OTC) gene on Xp21.1., a key enzyme of the urea cycle which we found to be expressed in AD brains but not in controls, as confirmed by RT-PCR. We also detected mRNA expression of all the other urea cycle enzymes in AD brains. Immunochemistry experiments revealed that the OTC expression was strictly restricted to vascular endothelial cells in brain. Furthermore, OTC activity was 880% increased in the CSF of probable AD cases compared with controls. We analysed the association of the OTC -389 G/A and -241 A/G promoter polymorphisms with the risk of developing AD. We observed that rare haplotypes may be associated with the risk of AD through a possible modulation of the methylation of the OTC promoter. In conclusion, our results suggest the involvement of a new pathway in AD brains involving the urea cycle.


Assuntos
Doença de Alzheimer/enzimologia , Expressão Gênica/fisiologia , Ornitina Carbamoiltransferase/metabolismo , Polimorfismo de Nucleotídeo Único , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Encéfalo/metabolismo , Análise Mutacional de DNA/métodos , Feminino , Genótipo , Humanos , Masculino , Análise em Microsséries/métodos , Ornitina Carbamoiltransferase/genética , Fatores Sexuais
17.
Bull Mem Acad R Med Belg ; 165(5-6): 231-4; discussion 235, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21510483

RESUMO

The history of the study by our group of the generation, the role and the effects of H2O2 in the thyroid, is summarized. The relations with thyroid diseases are discussed: myxedematous cretinism, thyroiditis, thyroid cancer, congenital hypothyroiddism, are discussed. A new role of H2O2 in the chemorepulsion of bacteria is proposed.


Assuntos
Peróxido de Hidrogênio/metabolismo , Oxidases Duais , Humanos , NADPH Oxidases/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Nódulo da Glândula Tireoide/metabolismo
18.
Endocr Rev ; 26(7): 944-84, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16174820

RESUMO

Recent identification of new selenocysteine-containing proteins has revealed relationships between the two trace elements selenium (Se) and iodine and the hormone network. Several selenoproteins participate in the protection of thyrocytes from damage by H(2)O(2) produced for thyroid hormone biosynthesis. Iodothyronine deiodinases are selenoproteins contributing to systemic or local thyroid hormone homeostasis. The Se content in endocrine tissues (thyroid, adrenals, pituitary, testes, ovary) is higher than in many other organs. Nutritional Se depletion results in retention, whereas Se repletion is followed by a rapid accumulation of Se in endocrine tissues, reproductive organs, and the brain. Selenoproteins such as thioredoxin reductases constitute the link between the Se metabolism and the regulation of transcription by redox sensitive ligand-modulated nuclear hormone receptors. Hormones and growth factors regulate the expression of selenoproteins and, conversely, Se supply modulates hormone actions. Selenoproteins are involved in bone metabolism as well as functions of the endocrine pancreas and adrenal glands. Furthermore, spermatogenesis depends on adequate Se supply, whereas Se excess may impair ovarian function. Comparative analysis of the genomes of several life forms reveals that higher mammals contain a limited number of identical genes encoding newly detected selenocysteine-containing proteins.


Assuntos
Sistema Endócrino/fisiologia , Selênio/fisiologia , Glândula Tireoide/fisiologia , Animais , Humanos
19.
Trends Cell Biol ; 10(10): 404-8, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10998591

RESUMO

Cell regulation and signal transduction are becoming increasingly complex, with reports of new cross-signalling, feedback, and feedforward regulations between pathways and between the multiple isozymes discovered at each step of these pathways. However, this information, which requires pages of text for its description, can be summarized in very simple schemes, although there is no consensus on the drawing of such schemes. This article presents a simple set of rules that allows a lot of information to be inserted in easily understandable displays.


Assuntos
Recursos Audiovisuais , Fenômenos Fisiológicos Celulares , Gráficos por Computador , Transdução de Sinais/fisiologia
20.
J Cell Biol ; 117(2): 383-93, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1313816

RESUMO

The mechanisms that generate the intercellular heterogeneity of functional and proliferation responses in a tissue are generally unknown. In the thyroid gland, this heterogeneity is peculiarly marked and it has been proposed that it could result from the coexistence of genetically different subpopulations of thyrocytes. To evaluate the heterogeneity of proliferative responses in primary culture of dog thyrocytes, we asked whether the progeny of cells having incorporated 3H thymidine in a first period of the culture could have a distinct proliferative fate during a second labeling period (incorporation of bromodeoxyuridine revealed by immunofluorescence staining combined with autoradiography of 3H thymidine). No growth-prone subpopulations were detected and the great majority of cells were found to response to either EGF or thyrotropin (TSH) through cAMP. However, only a fraction of cells replicated DNA at one given period and a clustered distribution of labeled cells within the monolayer, which was different for thymidine- or bromodeoxyuridine-labeled cells, indicates some local and temporal synchrony of neighboring cells. The TSH/cAMP-dependent division of thyrocytes preserved their responsiveness to both TSH and EGF mitogenic pathways. By contrast, cells that had divided during a momentary treatment with EGF lost the mitogenic sensitivity to TSH and cAMP (forskolin) but retained the sensitivity to EGF. Since cells that had not divided kept responsiveness to both TSH and EGF, this generated two subpopulations differing in mitogen responsiveness. The extinction of the TSH/cAMP-dependent mitogenic pathway was delayed (1-2 d) but stable. Cell fusion experiments suggest it was due to the induction of a diffusible intracellular inhibitor of the cAMP-dependent growth pathway. These findings provide a useful model of the generation of a qualitative heterogeneity in the cell sensitivity to various mitogens, which presents analogies with other epigenetic processes, such as differentiation and senescence. They shed a new light on the significance of the coexistence of different modes of cell cycle controls in thyroid epithelial cells.


Assuntos
AMP Cíclico/farmacologia , Fator de Crescimento Epidérmico/farmacologia , Glândula Tireoide/citologia , Tireotropina/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Fusão Celular , Células Cultivadas , Colforsina/farmacologia , DNA/biossíntese , Cães , Células Epiteliais , Epitélio/efeitos dos fármacos , Glândula Tireoide/efeitos dos fármacos
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