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PURPOSE: To determine whether folinic acid (FA) and thyroxine, in combination or alone, benefit psychomotor development in young patients with Down syndrome (DS). METHODS: The Assessment of Systematic Treatment With Folinic Acid and Thyroid Hormone on Psychomotor Development of Down Syndrome Young Children (ACTHYF) was a single-center, randomized, double-blind, placebo-controlled phase 3 trial in DS infants aged 6-18 months. Patients were randomly assigned to one of four treatments: placebo, folinic acid (FA), L-thyroxine, or FA+L-thyroxine, administered for 12 months. Randomization was done by age and sex. The primary endpoint was adjusted change from baseline in Griffiths Mental Development Scale global development quotient (GDQ) after 12 months. RESULTS: Of 175 patients randomized, 143 completed the study. The modified intention-to-treat (mITT) population included all randomized patients who did not prematurely discontinue due to elevated baseline thyroid stimulating hormone (TSH). Baseline characteristics in the mITT were well balanced between groups, with reliable developmental assessment outcomes. Adjusted mean change in GDQ in the mITT showed similar decreases in all groups (placebo: -5.10 [95% confidence interval (CI) -7.84 to -2.37]; FA: -4.69 [95% CI -7.73 to -1.64]; L-thyroxine: -3.89 [95% CI -6.94 to -0.83]; FA+L-thyroxine: -3.86 [95% CI -6.67 to -1.06]), with no significant difference for any active treatment group versus placebo. CONCLUSION: This trial does not support the hypotheses that thyroxine and/or folinic acid improve development of young children with DS or are synergistic. This trial is registered with ClinicalTrials.gov number, NCT01576705.
Assuntos
Síndrome de Down/tratamento farmacológico , Leucovorina/administração & dosagem , Desempenho Psicomotor/efeitos dos fármacos , Tiroxina/administração & dosagem , Método Duplo-Cego , Síndrome de Down/psicologia , Feminino , Humanos , Lactente , Análise de Intenção de Tratamento/métodos , Leucovorina/farmacologia , Masculino , Tiroxina/farmacologia , Tiroxina/uso terapêutico , Resultado do TratamentoRESUMO
In vitro angiogenesis assays are commonly used to assess pro- or anti-angiogenic drug properties. Extracellular matrix (ECM) substitutes such as Matrigel and collagen gel became very popular in in vitro 3D angiogenesis assays as they enable tubule formation by endothelial cells from culture or aortic rings. However, these assays are usually used with a single cell type, lacking the complex cellular interactions occurring during angiogenesis. Here, we report a novel angiogenesis assay using egg white as ECM substitute. We found that, similar to Matrigel, egg white elicited prevascular network formation by endothelial and/or smooth muscle cell coculture. This matrix was suitable for various cells from human, mouse, and rat origin. It is compatible with aortic ring assay and also enables vascular and tumor cell coculture. Through simple labeling (DAPI, Hoechst 33258), cell location and resulting prevascular network formation can easily be quantified. Cell transfection with green fluorescent protein improved whole cell visualization and 3D structure characterization. Finally, egg-based assay dedicated to angiogenesis studies represents a reliable and cost-effective way to produce and analyze data regarding drug effects on vascular cells.
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Neovascularização Fisiológica/efeitos dos fármacos , Animais , Animais Geneticamente Modificados , Aorta Torácica/citologia , Bisbenzimidazol , Técnicas de Cocultura/métodos , Colágeno , Combinação de Medicamentos , Avaliação Pré-Clínica de Medicamentos/métodos , Clara de Ovo , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Corantes Fluorescentes , Células Endoteliais da Veia Umbilical Humana , Humanos , Indóis , Laminina , Camundongos , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Proteoglicanas , Ratos , Especificidade da EspécieRESUMO
The transcription factor EGR2 is expressed in Schwann cells, where it controls peripheral nerve myelination. Mutations of EGR2 have been found in patients with congenital hypomyelinating neuropathy or Charcot-Marie-Tooth disease type 1D. In a patient with congenital amyelinating neuropathy, we observed pathological abnormalities recapitulating the peripheral nervous system phenotype of homozygous Egr2-null mice. This patient, born from consanguineous parents, showed no EGR2 immunoreactivity in Schwann cells and harbored a homozygous 10.7-kilobase-long deletion encompassing a myelin-specific enhancer of EGR2. This regulatory mutation is the first genetic abnormality associated with congenital amyelinating neuropathy in humans.
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Doença de Charcot-Marie-Tooth/genética , Doença de Charcot-Marie-Tooth/patologia , Proteína 2 de Resposta de Crescimento Precoce/genética , Elementos Facilitadores Genéticos/genética , Bainha de Mielina/patologia , Sequência de Bases , Feminino , Homozigoto , Humanos , Lactente , Recém-Nascido , Dados de Sequência Molecular , Linhagem , Reação em Cadeia da Polimerase , Deleção de SequênciaRESUMO
Most of the antiangiogenic strategies used in oncology principally target endothelial cells through the vascular endothelial growth factor (VEGF) pathway. Multiple kinase inhibitors can secondarily reduce mural cell stabilization of the vessels by blocking platelet-derived growth factor receptor (PDGFR) activity. However, sphingosine-1-phosphate (S1P), which is also implicated in mural cell recruitment, has yet to be targeted in clinical practice. We therefore investigated the potential of a simultaneous blockade of the PDGF and S1P pathways on the chemotactic responses of vascular smooth muscle cells (VSMCs) and the resulting effects of this blockade on breast tumor growth. Due to crosstalk between the S1P and PDGF pathways, we used AG1296 and/or VPC-23019 to inhibit PDGFR-ß and S1PR1/S1PR3 receptors, respectively. We showed that S1PR1 and S1PR3 are the principal receptors that mediate the S1P chemotactic signal on rat VSMCs and that they act synergistically with PDGFR-ß during PDGF-B signaling. We also showed that simultaneous blockade of the PDGFR-ß and S1PR1/S1PR3 signals had a synergistic effect, decreasing VSMC migration velocity toward endothelial cell and breast carcinoma cell-secreted cytokines by 65-90%. This blockade also strongly decreased the ability of VSMCs to form a three-dimensional cell network. Similar results were obtained with the combination of sunitinib malate (a VEGFR/PDGFR kinase inhibitor) and fingolimod (an S1P analog). Sunitinib malate is a clinically approved cancer treatment, whereas fingolimod is currently indicated only for treatment of multiple sclerosis. Orally administered, the combination of these drugs greatly decreased rat breast tumor growth in a syngeneic cancer model (Walker 256). This bi-therapy did not exert cumulative toxicity and histological analysis of the tumors revealed normalization of the tumor vasculature. The simultaneous blockade of these signaling pathways with sunitinib malate and fingolimod may provide an effective means of reducing tumor angiogenesis, and may improve the delivery of other chemotherapies.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma 256 de Walker/tratamento farmacológico , Neoplasias Mamárias Experimentais/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Aorta Torácica/patologia , Carcinoma 256 de Walker/irrigação sanguínea , Carcinoma 256 de Walker/patologia , Movimento Celular , Células Cultivadas , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Feminino , Cloridrato de Fingolimode , Indóis/administração & dosagem , Masculino , Neoplasias Mamárias Experimentais/irrigação sanguínea , Neoplasias Mamárias Experimentais/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/fisiologia , Transplante de Neoplasias , Propilenoglicóis/administração & dosagem , Proteínas Proto-Oncogênicas c-sis/farmacologia , Proteínas Proto-Oncogênicas c-sis/fisiologia , Pirróis/administração & dosagem , Ratos , Ratos Sprague-Dawley , Receptor beta de Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores de Lisoesfingolipídeo/metabolismo , Receptores de Lisoesfingolipídeo/fisiologia , Esfingosina/administração & dosagem , Esfingosina/análogos & derivados , Receptores de Esfingosina-1-Fosfato , Estatísticas não Paramétricas , Sunitinibe , Carga Tumoral/efeitos dos fármacos , Tirfostinas/farmacologiaRESUMO
The relationships between psychological stress and cognitive functions are still to be defined despite some recent progress. Clinically, we noticed that patients with Down syndrome (DS) may develop rapid neurocognitive decline and Alzheimer's disease (AD) earlier than expected, often shortly after a traumatic life event (bereavement over the leave of a primary caregiver, an assault, modification of lifestyle, or the loss of parents). Of course, individuals with DS are naturally prone to develop AD, given the triplication of chromosome 21. However, the relatively weak intensity of the stressful event and the rapid pace of cognitive decline after stress in these patients have to be noticed. It seems DS patients react to stress in a similar manner normal persons react to a very intense stress, and thereafter develop a state very much alike post-traumatic stress disorders. Unfortunately, only a few studies have studied stress-induced regression in patients with DS. Thus, we reviewed the biochemical events involved in psychological stress and found some possible links with cognitive impairment and AD. Interestingly, these links could probably be also applied to non-DS persons submitted to an intense stress. We believe these links should be further explored as a better understanding of the relationships between stress and cognition could help in many situations including individuals of the general population.
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In glial tumors, the loss of heterozygosity of the 1p and 19q chromosomal arms is thought to be a marker of good prognosis in oligodendroglial tumors. However, 1p and 19q loss of heterozygosity may be telomeric, interstitial, centromeric or affect the whole arm of the chromosome and the associations between these different patterns and tumor type, other molecular markers and patient prognosis remain unclear. We analyzed microsatellite markers in a region spanning the chromosome from the telomere to the centromere, to characterize the pattern of 1p and 19q loss of heterozygosity in 39 infiltrative gliomas, including astrocytomas, glioblastomas, oligoastrocytomas and oligodendrogliomas. We then studied the association between loss of heterozygosity and the expression of p53 protein and Olig2, as analyzed using immunohistochemistry, and epidermal growth factor receptor (EGFR) gene amplification, as investigated using fluorescence in situ hybridization (FISH). Finally, we assessed the influence of molecular markers on the overall survival of patients. We identified five different 1p19q loss of heterozygosity patterns among the tumors studied and found that loss of heterozygosity over the whole 1p arm was associated with loss of heterozygosity over the whole 19q arm in 90% of cases. 1p19q whole loss was present in all the classical oligodendrogliomas, whereas other 1p19q loss patterns predominated in oligoastrocytomas. 1p19q whole loss was also significantly associated with Olig2 overexpression, but was never observed in tumors overexpressing p53 protein. We also found that, among patients with contrast-enhancing tumors, those with 1p19q whole loss tended to survive for longer. In combination with classical histological and immunohistochemical data, 1p19q status determination provides pertinent information useful for (1) discriminating between histological types of gliomas and (2) identifying a subgroup of tumors that are associated with a better prognosis.
Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Glioma/genética , Proteínas do Tecido Nervoso/genética , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 19/genética , Receptores ErbB/genética , Feminino , Amplificação de Genes , Glioma/mortalidade , Glioma/patologia , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Estimativa de Kaplan-Meier , Perda de Heterozigosidade , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Fator de Transcrição 2 de Oligodendrócitos , Reação em Cadeia da Polimerase , PrognósticoRESUMO
In this review, we draw attention to the roles of calcitriol (1,25-dihydroxyvitamin D3) in the trophicity of the peripheral nervous system. Calcitriol has long been known to be crucial in phosphocalcium homeostasis. However, recent discoveries concerning its involvement in the immune system, anti-cancer defenses, and central nervous system development suggest a more pleiotropic role than previously thought. Several studies have highlighted the impact of calcitriol deficiency as a promoting factor of various central neurological diseases, such as multiple sclerosis, amyotrophic lateral sclerosis, Parkinson's disease, and Alzheimer's disease. Based on these findings and recent publications, a greater role for calcitriol may be envisioned in the peripheral nervous system. Indeed, calcitriol is involved in myelination, axonal homogeneity of peripheral nerves, and neuronal-cell differentiation. This may have useful clinical consequences, as calcitriol supplementation may be a simple means to avoid the onset and/or development of peripheral nervous-system disorders.
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Improvements of microarray techniques for genotyping purposes have focused on increasing the reliability of this method. Here we report the development of a genotyping method where a microarray was spotted with stemloop probes, especially designed to optimize the hybridization specificity of complementary DNA sequences. This accurate method was used to screen for four common disease-causing mutations involved in a neurological disorder called Charcot-Marie-Tooth disease (CMT). Healthy individuals' and patients' DNA were amplified and labeled by PCR and hybridized on microarray. The spot signal intensities were 81 to 408 times greater for perfect compared with mismatched target sequences, differing by only one nucleotide (discrimination ratio) for healthy individual "homozygous" DNA. On the other hand, "heterozygous" mutant DNA samples gave rise to signal intensity ratios close to 1, as expected. The genotypes obtained by this method were perfectly consistent with those determined by direct PCR sequencing. Cross-hybridization rates were very low, resulting in further multiplexing improvements. In this study, we also demonstrated the feasibility of real-time hybridization detection of labeled synthetic oligonucleotides with concentrations as low as 2.5 nM.
Assuntos
Análise Mutacional de DNA/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Mutação Puntual/genética , Sequência de Bases , Estudos de Casos e Controles , Doença de Charcot-Marie-Tooth/genética , Humanos , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Oligonucleotídeos/química , Oligonucleotídeos/genética , Sensibilidade e EspecificidadeRESUMO
Quantitative reverse transcription PCR (RT-PCR) has become an important tool for studying functional gene expression. However the most often used cycle threshold (CT)-based method, primarily related to the required amplification efficiency determination via serial dilution, can call into question the level of quantitative reliability and accuracy that can be achieved, in addition to the impracticalities inherent to CT-based methodologies. In this study, an alternative method, named the sigmoidal curve-fitting (SCF) method, was compared with the classic CT method for two target genes (XRCC4 and HIF-1alpha) and a reference gene (HPRT). The PCR conditions were optimized for each gene on a LightCycler apparatus. Fluorescence data were fitted to a four-parametric sigmoidal function, and the initial messenger RNA (mRNA) copy number was determined by a theoretical fluorescence (F0) value calculated from each fitting curve. The relative expression of the target gene versus that of the reference gene was calculated using an equation based upon these F0 values. The results show that the F0 value had a good linearity with the initial number of target genes between 10(7) and 10(1) copies. The reproducibility tests showed that the variations of initial target quantity were well reflected by F0 values. Relative expression of target gene calculated by the SCF method and by the CT method showed similar results. In our hands, the SCF method gave reliable results and a more precise error description of quantitative RT-PCR.
Assuntos
Proteínas de Ligação a DNA/biossíntese , Regulação da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Biotecnologia/métodos , Linhagem Celular Tumoral , Primers do DNA/química , DNA Complementar/metabolismo , Interpretação Estatística de Dados , Humanos , Modelos Estatísticos , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Transcrição GênicaRESUMO
Cell chemotaxis is frequently required in normal or pathological situations such as invasion, metastasis, and tumor angiogenesis and may involve many different cell types. At present, no device can simultaneously (i) make morphological observations, (ii) quantify cell migration, (iii) test multiple chemoattracting gradients, and (iv) analyze cell-cell interactions. We developed an agarose-based assay to address these questions. Two glass molds were designed, around which agarose gel could be poured to form specific well shapes. Using a vital nuclear stain (Hoechst 33258), we characterized the migration profile of adherent or suspension cells. Cells could be observed during the entire migration process. We were able to follow cells moving toward chemoattractants or being repulsed by other molecules, and we could estimate average migration speed. Using this inexpensive assay, we were able to obtain precise, reproducible results concerning the chemotactic behavior of different cell types. The resulting data differentiated between chemokinetic and chemotactic movement. Chemotactic potencies could be compared using different criteria, such as the number of attracted cells, induced speed, and morphological aspect. This improved agarose assay appears to be a reliable and inexpensive alternative to other available chemotaxis study tools.
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Bioensaio/instrumentação , Técnicas de Cultura de Células/instrumentação , Quimiotaxia/efeitos dos fármacos , Quimiotaxia/fisiologia , Análise de Injeção de Fluxo/instrumentação , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Sefarose/química , Bioensaio/métodos , Técnicas de Cultura de Células/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Citometria de Fluxo/instrumentação , Citometria de Fluxo/métodos , Análise de Injeção de Fluxo/métodos , Géis/químicaRESUMO
The molecular events favoring lymphangiogenic pathways for tumor growth and dissemination are not perfectly understood, nor are the expression patterns of lymphangiogenic biomarkers such as the VEGFR-3 receptor and its ligands, VEGF-C and VEGF-D. In particular, VEGFR-3 expression is not restricted to the lymphatic endothelium, but is found on some cancer cells and other cell types. A quantitative RT-PCR method was set up to measure the mRNA levels of VEGFR-3, VEGF-C and VEGF-D. With this method, a very low detection threshold was obtained when tested on 17 different human cell types. It was found that, in contrast to VEGF-D mRNA, the VEGFR-3 and VEGF-C mRNAs were not expressed in all the cell types studied, and that blood cells expressed high VEGFR-3 mRNA levels compared to solid tumor cells. As a result, quantitative RT-PCR is considered to be a highly reliable and reproducible technique that could help elucidate lymphangiogenic marker patterns of expression and function in cancer.
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RNA Mensageiro/biossíntese , Fator C de Crescimento do Endotélio Vascular/genética , Fator D de Crescimento do Endotélio Vascular/genética , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/genética , Linhagem Celular Tumoral , Humanos , Melanoma/genética , Melanoma/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/metabolismo , Linfócitos T/fisiologia , Fator C de Crescimento do Endotélio Vascular/biossíntese , Fator D de Crescimento do Endotélio Vascular/biossíntese , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/biossínteseRESUMO
Several genes have been involved in drug resistance but none are currently used in the drug decision process. To address this problem, mRNA levels were measured for the 5-fluorouracil metabolism-related genes, thymidylate synthase, thymidine phosphorylase and dihydropyrimidine dehydrogenase in tumor samples of 40 patients with synchronous metastatic colon cancer by quantitative RT-PCR. Drug response and overall survival were also obtained for each patient. A logistic regression model was defined to calculate a response predicting score (RPS) with gene expression levels. This RPS split responders from nonresponders as, at the best statistical threshold (0.35), the area of receiver operating characteristic (ROC) curve established with this method was 0.82 and sensitivity and specificity were respectively 100% and 65.4%. Furthermore patients with scores above 0.35 tended to have better overall survival than those with a score less than 0.35 (p = 0.09).
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Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/uso terapêutico , Idoso , Sequência de Bases , Neoplasias Colorretais/patologia , Primers do DNA , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e EspecificidadeRESUMO
UNLABELLED: Before studying the impact of 2-deoxy-2-[F-18]fluoro-D-glucose (FDG) imaging with a dual-head coincidence gamma camera (DHC) for the follow-up of animal tumor models, we wanted to optimize this technique. METHODS: Three different animal tumor models (osteosarcoma, melanoma, and breast cancer) were studied after FDG injection. Dynamic and dual time point FDG/DHC imaging were studied from one hour to five hours postinjection. In vitro tumor cell FDG uptake was assessed in eight different tumor cell lines. In one model (osteosarcoma), tumor growth, lung metastasis emergence, and survival were assessed by classical clinical follow-up and compared to FDG imaging in a control group (n = 6) and in a group treated by endostatin liposome complexes (n = 6). RESULTS: Images obtained five hours after injection were more reliable for tumor growth follow-up than standard images (one hour). In vitro tumor cell FDG uptake confirmed in vivo imaging studies. In eight different tumor cell lines the FDG uptake was higher after five hours incubation than after one hour (p < 0.002). With FDG follow-up, we found that FDG uptake was strongly correlated with survival and that lung metastasis larger than 5 mm could be detected. CONCLUSION: Using the optimization proposed above, DHC/FDG functional imaging seems to be a powerful tool to study rat tumor models and to help develop novel cancer therapies.
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Fluordesoxiglucose F18 , Câmaras gama , Neoplasias/metabolismo , Animais , Linhagem Celular Tumoral , Diagnóstico por Imagem , Modelos Animais de Doenças , Fluordesoxiglucose F18/farmacologia , Seguimentos , Humanos , Metástase Neoplásica/patologia , Transplante de Neoplasias , Neoplasias/diagnóstico , Neoplasias/patologia , Ratos , Ratos Sprague-Dawley , Taxa de Sobrevida , Fatores de TempoRESUMO
Platelet Derived Growth Factor (PDGF) and sphingosine-1-phosphate (S1P) pathways play a key role in mural cell recruitment during tumor growth and angiogenesis. Fingolimod, a S1P analogue, has been shown to exert antitumor and antiangiogenic properties. However, molecular targets and modes of action of fingolimod remain unclear. In this study, we confirmed the antagonizing action of S1P and PDGF-B on rat vascular smooth muscle cell (VSMCs) growth and migration. We then compared siRNA and/or fingolimod (100 nM) treatments on PDGFR-ß, S1PR1 S1PR2 and S1PR3 expression. Fingolimod induced a 50% reduction in S1PR3 protein expression which was cumulative with that obtained with anti-S1PR3 siRNA. We found that siRNA-induced inhibition of both PDGFR-ß and S1PR3 was the most effective means to block VSMC migration induced by PDGF-B. Finally, we observed that fingolimod treatment associated with anti-S1PR1 siRNA principally inhibited VSMC growth while in combination with anti-S1PR3 siRNA it strongly inhibited VSMC migration. These results suggest that for rat VSMCs, the PDGFR-S1PR1 pathway is predominantly dedicated to cell growth while PDGFR-S1PR3 stimulates cell migration. As an S1P analogue, fingolimod is considered a potent activator of S1PR1 and S1PR3. However, its action on the PDGFR-S1PR platform appears to be dependent on S1PR1 and S1PR3 specific downregulation. Considering that the S1P pathway has already been shown to exert various crosstalks with tyrosine kinase pathways, it seems of great interest to evaluate fingolimod potential in combination with the numerous tyrosine kinase inhibitors used in oncology.
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Movimento Celular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Propilenoglicóis/farmacologia , Proteínas Proto-Oncogênicas c-sis/farmacologia , Receptores de Lisoesfingolipídeo/metabolismo , Esfingosina/análogos & derivados , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Cloridrato de Fingolimode , Imuno-Histoquímica , Masculino , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo , Interferência de RNA , Ratos , Ratos Sprague-Dawley , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores de Lisoesfingolipídeo/genética , Transdução de Sinais/efeitos dos fármacos , Esfingosina/farmacologia , Receptores de Esfingosina-1-FosfatoRESUMO
Breast cancer is the most frequent spontaneous malignancy diagnosed in women and is characterized by a broad histological diversity. Progression of the disease has a metastasizing trend and can be resistant to hormonal and chemotherapy. Animal models have provided some understanding of these features and have allowed new treatments to be proposed. However, these models need to be revised because they have some limitations in predicting the clinical efficacy of new therapies. In this review, we discuss the biological criteria to be taken into account for a realistic animal model of breast cancer graft (tumor implantation site, animal immune status, histological diversity, modern imaging). We emphasize the need for more stringent monitoring criteria, and suggest adopting the human RECIST (Response Evaluation Criteria in Solid Tumors) criteria to evaluate treatments in animal models.
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Neoplasias da Mama/tratamento farmacológico , Modelos Animais de Doenças , Transplante de Neoplasias , Animais , Antineoplásicos/uso terapêutico , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Resultado do Tratamento , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
PURPOSE: Although intestinal motility disorders often complicate the postoperative surgical management of newborns with congenital intestinal atresia, their pathogenesis remains unclear. Animal models of prenatal intestinal obstruction have been mainly developed in the lamb and the chicken. Despite new insights brought by these models, they have one or more limitations, such as high fetal mortality rates, high costs, long gestation periods, and an insufficient number of fetuses per litter. Moreover, some species are phylogenetically distant from mammals. METHODS: We developed a reproducible model of prenatal intestinal obstruction in the rat to study the histologic changes induced by the obstruction. We report, the technical devices and the first assessment of this atresia model in a didactic way to allow other researchers to easily reproduce the model. RESULTS: Prenatal intestinal obstructions in this study fulfilled all the macroscopic and histologic criteria usually listed by other models of prenatal intestinal obstruction that have been developed in other species. Furthermore with our model, we obtained a high success rate at a low cost. CONCLUSIONS: We presented in this study a reproducible model of prenatal intestinal obstruction in the rat with the macroscopical and histologic features of prenatal intestinal obstruction.
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Modelos Animais de Doenças , Doenças Fetais/patologia , Obstrução Intestinal/patologia , Animais , Feminino , Doenças Fetais/cirurgia , Imuno-Histoquímica , Obstrução Intestinal/mortalidade , Obstrução Intestinal/cirurgia , Gravidez , Diagnóstico Pré-Natal , Probabilidade , Distribuição Aleatória , Ratos , Ratos Wistar , Valores de Referência , Sensibilidade e Especificidade , Taxa de SobrevidaRESUMO
BACKGROUND: Seven genes involved in folate metabolism are located on chromosome 21. Previous studies have shown that folate deficiency may contribute to mental retardation in Down's syndrome (DS). METHODOLOGY: We investigated the effect of oral folate supplementation (daily dose of 1.0+/-0.3 mg/kg) on cognitive functions in DS children, aged from 3 to 30 months. They received 1 mg/kg leucovorin or placebo daily, for 12 months, in a single-centre, randomised, double-blind study. Folinic acid (leucovorin, LV) was preferred to folic acid as its bioavailability is higher. The developmental age (DA) of the patients was assessed on the Brunet-Lezine scale, from baseline to the end of treatment. RESULTS: The intent-to-treat analysis (113 patients) did not show a positive effect of leucovorin treatment. However, it identified important factors influencing treatment effect, such as age, sex, and concomitant treatments, including thyroid treatment in particular. A per protocol analysis was carried out on patients evaluated by the same examiner at the beginning and end of the treatment period. This analysis of 87 patients (43 LV-treated vs. 44 patients on placebo) revealed a positive effect of leucovorin on developmental age (DA). DA was 53.1% the normal value with leucovorin and only 44.1% with placebo (p<0.05). This positive effect of leucovorin was particularly strong in patients receiving concomitant thyroxin treatment (59.5% vs. 41.8%, p<0.05). No adverse event related to leucovorin was observed. CONCLUSION: These results suggest that leucovorin improves the psychomotor development of children with Down's syndrome, at least in some subgroups of the DS population, particularly those on thyroxin treatment. TRIAL REGISTRATION: ClinicalTrials.gov, NCT00294593.
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Síndrome de Down/psicologia , Leucovorina/administração & dosagem , Glândula Tireoide/fisiopatologia , Pré-Escolar , Método Duplo-Cego , Síndrome de Down/fisiopatologia , Feminino , Humanos , Lactente , Masculino , PlacebosRESUMO
UNLABELLED: The large number of studies devoted to the effect of ultraviolet light on biological systems, contrasts with the lack of experimental data concerning the direct effects of visible light. It has been shown that blue light inhibited the growth of B16F10 melanoma cell lines and reduced the percentage of S phase cells. Yet these effects are poorly understood. MATERIALS AND METHODS: Two cell lines and irradiation with blue light were used. Cell mortality and a possible mechanism of action were investigated. RESULTS: Exposure of B16F10 melanoma and bovine endothelial cells to blue light (wavelength 450 nm, 10 J/cm(2) from a Waldman lamp) induced a rapid and large reduction in viability followed by the death of virtually all the irradiated cells within 24 h. These results led us to expose a patient with haemorrhagic cutaneous melanoma metastasis to blue light. Irradiation led to an immediate arrest of haemorrhage, an inhibition of tumour growth and extensive tumour necrosis 24h after irradiation. CONCLUSION: Exposure to blue light may offer new approaches to the treatment of superficial skin carcinomas in humans.
Assuntos
Células Endoteliais/efeitos da radiação , Melanoma Experimental/terapia , Fototerapia/métodos , Animais , Bovinos , Sobrevivência Celular/efeitos da radiação , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Luz , Peroxidação de Lipídeos/efeitos da radiação , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , CamundongosRESUMO
The enteric nervous system maturation occurs during embryonic life and continues after birth. Some prenatal events on the digestive tract such as intestinal atresia have been shown to dramatically alter this maturation. Thus, we developed a fetal rat model of intestinal atresia by surgically obstructing the small bowel at embryonic day E18. Fetuses were removed at day E21, and small bowels sections were examined by immuno-histochemistry. Synaptophysin and smooth muscle actin staining was used to define the cellular aspect. Labeling revealed marked alterations of the myenteric plexus in the lower extremity of the occluded small bowel. At day E21, the myenteric plexus of the lower part and the 2 muscle layers surrounding it, retained the staining pattern observed at day E17. This cellular pattern was classified as: immature (aspect at day E17) vs. mature (aspect of day E21) by 3 pathologists not familiar with the study. The number of samples with an immature cellular pattern at the lower end of the occluded bowel was different from that observed for the upper end (Mac Nemar test, p<0.008). Our study suggests that a prenatal obstruction induces a maturation delay of the myenteric plexus downstream of the obstruction. This might be important for pediatric purposes.
Assuntos
Atresia Intestinal/embriologia , Obstrução Intestinal/embriologia , Intestino Delgado/inervação , Plexo Mientérico/anormalidades , Complicações na Gravidez/patologia , Actinas/metabolismo , Animais , Feminino , Doenças Fetais/patologia , Imuno-Histoquímica , Atresia Intestinal/complicações , Obstrução Intestinal/complicações , Intestino Delgado/embriologia , Músculo Liso/embriologia , Músculo Liso/inervação , Plexo Mientérico/embriologia , Gravidez , Ratos , Sinaptofisina/metabolismoRESUMO
We previously developed a highly specific method for detecting SNPs with a microarray-based system using stem-loop probes. In this paper we demonstrate that coupling a multiplexing procedure with our microarray method is possible for the simultaneous detection and genotyping of four point mutations, in three different genes, involved in Charcot-Marie-Tooth disease. DNA from healthy individuals and patients was amplified, labeled with Cy3 by multiplex PCR; and hybridized to microarrays. Spot signal intensities were 18 to 74 times greater for perfect matches than for mismatched target sequences differing by a single nucleotide (discrimination ratio) for "homozygous" DNA from healthy individuals. "Heterozygous" mutant DNA samples gave signal intensity ratios close to 1 at the positions of the mutations as expected. Genotyping by this method was therefore reliable. This system now combines the principle of highly specific genotyping based on stem-loop structure probes with the advantages of multiplex analysis.