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1.
Bone Marrow Transplant ; 59(6): 838-848, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38443704

RESUMO

There is currently no consensus on the role of upfront autologous transplantation (ASCT) for patients with peripheral T-cell lymphomas (PTCL), especially in patients achieving first complete remission (CR1) following chemotherapy, and data in the literature is conflicting. A systematic review and meta-analysis was performed to address this question. We searched key databases from January 2000 to February 2022. Six prospective and eleven retrospective studies were included among 2959 unique records. Median follow up in these studies ranged from 22 to 94 months. There was a trend towards benefit in PFS (HR = 0.80, 95% CI 0.62-1.05, p = 0.11) and OS (HR = 0.79, 95% CI 0.57-1.09, p = 0.15) in the ASCT compared to chemotherapy only group. Importantly, in transplant eligible patients in CR1, a significant benefit was demonstrated in both OS (HR = 0.59, 95% CI 0.36-0.95, p = 0.03) and PFS (HR = 0.61, 95% CI 0.47-0.81, p = 0.0004) in the ASCT group. Amongst the nodal PTCL subgroups, ASCT showed a significant PFS benefit for the AITL subgroup (HR = 0.43, 95% CI 0.20-0.94, p < 0.03) but not PTCL-NOS or ALK-ve ALCL subgroups. Our findings support upfront ASCT for transplant eligible PTCL patients achieving CR1 post chemotherapy. In particular, patients with AITL exhibited a significantly better PFS after upfront ASCT.


Assuntos
Linfoma de Células T Periférico , Indução de Remissão , Transplante Autólogo , Linfoma de Células T Periférico/terapia , Linfoma de Células T Periférico/mortalidade , Humanos , Transplante Autólogo/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Autoenxertos
3.
Gynecol Obstet Fertil Senol ; 48(2): 187-195, 2020 02.
Artigo em Francês | MEDLINE | ID: mdl-31634589

RESUMO

Of the 800 pesticides used worldwide, about 650 can affect the functioning of the endocrine system: endocrine disrupting pesticides (EDPs). Dietary or environmental exposure to EDPs is a concern, as their presence is currently demonstrated in most biological fluids. Some EDPs are prohibited, classified as carcinogenic, others are "probable" or "possible" carcinogens when there is limited evidence of their tumor effect. The impact of EDPs on breasts is not well known to date. However, since most EDPs have a long half-life and are lipophilic, breasts, composed mainly of adipose tissue, are a suitable site for their concentration. The objective of our review was to analyze the impact of EDPs related to our environmental exposure on breast cancer risk, through an analysis of recent literature, including epidemiological and biological data. Our review showed a positive association between the presence of EDPs and breast cancer, especially among women farmers or EDPs users but also in the general population. Studies on breast tumors have found a higher concentration of EDPs in estrogen-sensitive tumors. As for mortality, studies are contradictory, but confirm the dangerousness of some EDPs. The different series analyzed have several limitations, such as the low number of EDPs evaluated, small numbers and insufficient follow up. The potentiating effect of different EDPs used concomitantly and the window of exposure to these substances are parameters to be assessed.


Assuntos
Neoplasias da Mama/epidemiologia , Disruptores Endócrinos/efeitos adversos , Praguicidas/efeitos adversos , Neoplasias da Mama/química , Disruptores Endócrinos/análise , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Fatores de Risco
4.
Eur J Pediatr ; 178(10): 1545-1558, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31463766

RESUMO

We sought to establish guidelines for hygiene care in newborns based on a systematic review of the literature and grading of evidence using the Groupe de Réflexion et d'Evaluation de l'Environement des Nouveau-nés (GREEN) methodology. We examined 45 articles and 4 reports from safety agencies. These studies recommend a tub bath (rather than a sponge bath) for full-term infants and a swaddle bath for preterm newborns. They also recommend against daily cleansing of preterm infants. The literature emphasized that hygiene care must consider the clinical state of the newborn, including the level of awareness and behavioral responses. Hospitalized newborns treated with topical agents may also experience high exposure to potentially harmful excipients of interest. Caregivers should therefore be aware of the excipients present in the different products they use. In high-resource countries, the available data do not support the use of protective topical agents for preterm infants.Conclusions: We recommend individualization of hygiene care for newborns. There is increasing concern regarding the safety of excipients in topical agents that are used in neonatology. A multidisciplinary approach should be used to identify an approach that requires lower levels of excipients and alternative excipients. What is known: • Hygiene care is one of the most basic and widespread types of care received by healthy and sick newborns worldwide. • There is no current guideline on hygiene for preterm or hospitalized term newborn. What is new: • The French Group of Reflection and Evaluation of the environment of Newborns (GREEN) provided here guidelines based on the current body of evidence. • Caregivers should be aware of the many issues related to hygiene care of newborns including newborns' behavioral responses to hygiene care, exposition to excipients of interest, and the potential risk of protective topical agents in a preterm infant. provided here guidelines based on the current body of evidence. • Caregivers should be aware of the many issues related to hygiene care of newborns including newborns' possible behavioral responses to hygiene care, exposition to excipients of interest and the potential risk of protective topical agents in a preterm infant.


Assuntos
Higiene/normas , Cuidado do Lactente/normas , Guias de Prática Clínica como Assunto , Administração Tópica , França , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Neonatologia/métodos , Fenômenos Fisiológicos da Pele
5.
Phys Chem Chem Phys ; 18(4): 3188-96, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26743449

RESUMO

Prussian blue analogs (PBAs) are materials well known for their bulk physical and (electro)-chemical properties, with an outstanding selectivity for caesium in ion exchange processes. Crystalline nano-tiles, made of copper based PBA, are produced and dispersed in water by tuning their electrostatic interactions. The shape and size of the nano-crystals are determined by combining scattering, microscopic and spectral techniques. We show here that Cu-PBA nano-tiles form planar superstructures by an edge to edge self-assembly process controlled by specific cation effect and ionic strength. Sedimentation and (re-)dispersion of the nano-tiles are found to be fully reversible. This switchable anisotropic self-assembly triggered by salt stimulus makes PBA nanocrystals potentially interesting for applications.

6.
Oncogene ; 33(47): 5457-66, 2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-24240690

RESUMO

We show that expression of the microtubule depolymerizing kinesin KIF2C is induced by transformation of immortalized human bronchial epithelial cells (HBEC) by expression of K-Ras(G12V) and knockdown of p53. Further investigation demonstrates that this is due to the K-Ras/ERK1/2 MAPK pathway, as loss of p53 had little effect on KIF2C expression. In addition to KIF2C, we also found that the related kinesin KIF2A is modestly upregulated in this model system; both proteins are expressed more highly in many lung cancer cell lines compared to normal tissue. As a consequence of their depolymerizing activity, these kinesins increase dynamic instability of microtubules. Depletion of either of these kinesins impairs the ability of cells transformed with mutant K-Ras to migrate and invade matrigel. However, depletion of these kinesins does not reverse the epithelial to mesenchymal transition (EMT) caused by mutant K-Ras. Our studies indicate that increased expression of microtubule destabilizing factors can occur during oncogenesis to support enhanced migration and invasion of tumor cells.


Assuntos
Carcinoma Broncogênico/genética , Transformação Celular Neoplásica , Genes ras , Cinesinas/metabolismo , Proteína Supressora de Tumor p53/genética , Brônquios/citologia , Carcinoma Broncogênico/patologia , Movimento Celular/genética , Citoesqueleto/genética , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Cinesinas/genética , Microtúbulos/metabolismo , Mutação , Transdução de Sinais/genética
7.
Oncogenesis ; 2: e63, 2013 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-23958853

RESUMO

The developmental transcription factor NeuroD1 is anomalously expressed in a subset of aggressive neuroendocrine tumors. Previously, we demonstrated that TrkB and neural cell adhesion molecule (NCAM) are downstream targets of NeuroD1 that contribute to the actions of neurogenic differentiation 1 (NeuroD1) in neuroendocrine lung. We found that several malignant melanoma and prostate cell lines express NeuroD1 and TrkB. Inhibition of TrkB activity decreased invasion in several neuroendocrine pigmented melanoma but not in prostate cell lines. We also found that loss of the tumor suppressor p53 increased NeuroD1 expression in normal human bronchial epithelial cells and cancer cells with neuroendocrine features. Although we found that a major mechanism of action of NeuroD1 is by the regulation of TrkB, effective targeting of TrkB to inhibit invasion may depend on the cell of origin. These findings suggest that NeuroD1 is a lineage-dependent oncogene acting through its downstream target, TrkB, across multiple cancer types, which may provide new insights into the pathogenesis of neuroendocrine cancers.

8.
Arch Pediatr ; 20(9): 1006-10, 2013 Sep.
Artigo em Francês | MEDLINE | ID: mdl-23880250

RESUMO

Breastfeeding is a public health issue: health expenditures related to not breastfeeding have been evaluated in the US and the UK, annually amounting to billions of dollars and tens of millions of pounds. Breastfeeding is also a family issue, and this intimate practice involves the presence of emotions and feelings going beyond rationality. Healthcare professionals are responsible for promoting health in the physical, mental, and social domains. Information and individualized support are essential to enable parents to make the best possible choice and play an active role in their own health and that of their child. There are communication and support tools to help build a trusting relationship between professionals and parents, to provide relevant information, and to assist parents in their reflection, while supporting them in their choices. In France, healthcare professionals have available a tool for intervention and education proposed by the French Institute for Health Promotion and Health Education (Institut national de prévention et d'éducation pour la santé, INPES) in the Pregnancy and Parenting section. It provides a high degree of homogeneity in the various healthcare professional's interventions occurring during pregnancy and thereafter. It aims to promote and strengthen parenting skills. Thus, support for breastfeeding is part of a dynamic process to support parenting, focused on people, not on the object, for both ethical and effectiveness reasons.


Assuntos
Aleitamento Materno , Comportamento de Escolha , Tomada de Decisões , Educação em Saúde , Humanos , Lactente , Recém-Nascido , Saúde Pública , Apoio Social
9.
J Vet Pharmacol Ther ; 36(6): 617-20, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23682764

RESUMO

A risk assessment conducted in 2007 identified significant knowledge gaps about tissue residues of melamine and related triazine analogs such as cyanuric acid in animals that had eaten contaminated food. The USFDA subsequently designed studies to determine residue levels in muscle, serum, and kidneys of catfish and trout given a single gavage dose of 20 mg/kg body weight (BW) of melamine, cyanuric acid, or 20 mg/kg BW of both compounds simultaneously. Renal triazines were determined by LC-MS/MS at postdose days 1, 3, 7, 14, 28 (and day 42 for trout). When dosed individually, melamine and cyanuric acid kidney residues depleted much faster than those in fish given both compounds together. Combined dose residue depletion was punctuated by extreme outliers due to the formation of persistent renal melamine cyanurate crystals.


Assuntos
Ictaluridae , Oncorhynchus mykiss , Triazinas/farmacocinética , Animais , Resíduos de Drogas , Rim/metabolismo , Triazinas/metabolismo
10.
Oncogene ; 32(34): 4034-42, 2013 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-22964644

RESUMO

KRAS mutations are one of the most common driver mutations in non-small-cell lung cancer (NSCLC) and finding druggable target molecules to inhibit oncogenic KRAS signaling is a significant challenge in NSCLC therapy. We recently identified epiregulin (EREG) as one of several putative transcriptional targets of oncogenic KRAS signaling in both KRAS-mutant NSCLC cells and immortalized bronchial epithelial cells expressing ectopic mutant KRAS. In the current study, we found that EREG is overexpressed in NSCLCs harboring KRAS, BRAF or EGFR mutations compared with NSCLCs with wild-type KRAS/BRAF/EGFR. Small interfering RNAs (siRNAs) targeting mutant KRAS, but not an siRNA targeting wild-type KRAS, significantly reduced EREG expression in KRAS-mutant and EREG-overexpressing NSCLC cell lines. In these cell lines, EREG expression was downregulated by MEK and ERK inhibitors. Importantly, EREG expression significantly correlated with KRAS expression or KRAS copy number in KRAS-mutant NSCLC cell lines. Further expression analysis using 89 NSCLC specimens showed that EREG was predominantly expressed in NSCLCs with pleural involvement, lymphatic permeation or vascular invasion and in KRAS-mutant adenocarcinomas. In addition, multivariate analysis revealed that EREG expression is an independent prognostic marker and EREG overexpression in combination with KRAS mutations was associated with an unfavorable prognosis for lung adenocarcinoma patients. In KRAS-mutant and EREG overexpressing NSCLC cells, siRNA-mediated EREG silencing inhibited anchorage-dependent and -independent growth and induced apoptosis. Our findings suggest that oncogenic KRAS-induced EREG overexpression contributes to an aggressive phenotype and could be a promising therapeutic target in oncogenic KRAS-driven NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Fator de Crescimento Epidérmico/genética , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Idoso , Apoptose/genética , Butadienos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular , Linhagem Celular Tumoral , Fator de Crescimento Epidérmico/metabolismo , Epirregulina , Receptores ErbB/genética , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Nitrilas/farmacologia , Fenótipo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras) , Pirazóis/farmacologia , Piridazinas/farmacologia , Interferência de RNA , Proteínas ras/metabolismo
11.
J Exp Bot ; 63(14): 5035-43, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22511804

RESUMO

To investigate the involvement of Rhizobium etli cbb(3) oxidase in the response of Phaseolus vulgaris to drought, common bean plants were inoculated with the R. etli strain, CFNX713, overexpressing this oxidase in bacteroids (cbb(3)(+)) and subjected to drought conditions. The negative effect of drought on plant and nodule dryweight, nitrogen content, and nodule functionality was more pronounced in plants inoculated with the wild-type (WT) strain than in those inoculated with the cbb(3)(+) strain. Regardless of the plant treatment, bacteroids produced by the cbb(3)(+) strain showed higher respiratory capacity than those produced by the WT strain. Inoculation of plants with the cbb(3)(+) strain alleviated the negative effect of a moderate drought on the respiratory capacity of bacteroids and the energy charge of the nodules. Expression of the FixP and FixO components of the cbb(3) oxidase was higher in bacteroids of the cbb(3)(+) strain than in those of the WT strain under all experimental conditions. The decline in sucrose synthase activity and the decrease in dicarboxylic acids provoked by moderate drought stress were more pronounced in nodules from plants inoculated with the WT strain than in those inoculated with the cbb(3)(+) strain. Taken together, these results suggest that inoculation of plants with a R. etli strain having enhanced expression of cbb(3) oxidase in bacteroids reduces the sensitivity of P. vulgaris-R. etli symbiosis to drought and can modulate carbon metabolism in nodules.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Regulação Bacteriana da Expressão Gênica , Fixação de Nitrogênio , Phaseolus/microbiologia , Rhizobium etli/enzimologia , Rhizobium etli/genética , Adaptação Fisiológica , Secas , Phaseolus/crescimento & desenvolvimento , Phaseolus/fisiologia , Simbiose
12.
Br J Cancer ; 106(1): 116-25, 2012 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-22158273

RESUMO

BACKGROUND: Over the last decade, several drugs that inhibit class I and/or class II histone deacetylases (HDACs) have been identified, including trichostatin A, the cyclic depsipeptide FR901228 and the antibiotic apicidin. These compounds have had immediate application in cancer research because of their ability to reactivate aberrantly silenced tumour suppressor genes and/or block tumour cell growth. Although a number of HDAC inhibitors are being evaluated in preclinical cancer models and in clinical trials, little is known about the differences in their specific mechanism of action and about the unique determinants of cancer cell sensitivity to each of these inhibitors. METHODS: Using a combination of cell viability assays, HDAC enzyme activity measurements, western blots for histone modifications, microarray gene expression analysis and qRT-PCR, we have characterised differences in trichostatin A vs depsipeptide-induced phenotypes in lung cancer, breast cancer and skin cancer cells and in normal cells and have then expanded these studies to other HDAC inhibitors. RESULTS: Cell viability profiles across panels of lung cancer, breast cancer and melanoma cell lines showed distinct sensitivities to the pan-inhibitor TSA compared with the class 1 selective inhibitor depsipeptide. In several instances, the cell lines most sensitive to one inhibitor were most resistant to the other inhibitor, demonstrating these drugs act on at least some non-overlapping cellular targets. These differences were not explained by the HDAC selectivity of these inhibitors alone since apicidin, which is a class 1 selective compound similar to depsipeptide, also showed a unique drug sensitivity profile of its own. TSA had greater specificity for cancer vs normal cells compared with other HDAC inhibitors. In addition, at concentrations that blocked cancer cell viability, TSA effectively inhibited purified recombinant HDACs 1, 2 and 5 and moderately inhibited HDAC8, while depsipeptide did not inhibit the activity of purified HDACs in vitro but did in cellular extracts, suggesting a potentially indirect action of this drug. Although both depsipeptide and TSA increased levels of histone acetylation in cancer cells, only depsipeptide decreased global levels of transcriptionally repressive histone methylation marks. Analysis of gene expression profiles of an isogenic cell line pair that showed discrepant sensitivity to depsipeptide, suggested that resistance to this inhibitor may be mediated by increased expression of multidrug resistance genes triggered by exposure to chemotherapy as was confirmed by verapamil studies. CONCLUSION: Although generally thought to have similar activities, the HDAC modulators trichostatin A and depsipeptide demonstrated distinct phenotypes in the inhibition of cancer cell viability and of HDAC activity, in their selectivity for cancer vs normal cells, and in their effects on histone modifications. These differences in mode of action may bear on the future therapeutic and research application of these inhibitors.


Assuntos
Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Neoplasias/patologia , Oligopeptídeos/farmacologia , Sequência de Bases , Western Blotting , Linhagem Celular Tumoral , Metilação de DNA , Primers do DNA , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Reação em Cadeia da Polimerase em Tempo Real
13.
Case Rep Dermatol ; 2(2): 156-164, 2010 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-21076689

RESUMO

A 72-year-old female and a 57-year-old male with chronic hepatitis C were treated with a combination therapy of pegylated interferon (PEG-IFN)-α 2a (180 µg s.c. once a week) and ribavirin (1,000 mg orally daily). This resulted in the destruction of melanocytes at the injection site in both patients. In the male patient, the depigmentation progressed to the surrounding skin area. The dermatologist concurred with vitiligo as the diagnosis in both patients. Injection and surrounding site vitiligo associated with PEG-IFN-α 2b treatment for hepatitis C was noticed in previous case studies. For the first time, the case reports below highlight the same immunological adverse event secondary to PEG IFN-α 2a/ribavirin combination therapy and explain, in part, the complex interaction between host immune response and viral genotype. In addition, we systematically review drug-induced vitiligo and autoimmune diseases associated with the depigmentation disorder.

14.
Appl Environ Microbiol ; 76(13): 4587-91, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20472732

RESUMO

Phylogenetic analysis of 16S rRNA, nodC, and nifH genes of four bacterial strains isolated from root nodules of Phaseolus vulgaris grown in Morocco soils were identified as Burkholderia phymatum. All four strains formed N(2)-fixing nodules on P. vulgaris and Mimosa, Acacia, and Prosopis species and reduced acetylene to ethylene when cultured ex planta.


Assuntos
Burkholderia/classificação , Burkholderia/isolamento & purificação , Fixação de Nitrogênio , Phaseolus/microbiologia , Microbiologia do Solo , Acacia/microbiologia , Acetileno/metabolismo , Proteínas de Bactérias/genética , Burkholderia/genética , Burkholderia/metabolismo , Meios de Cultura , Etilenos/metabolismo , Mimosa/microbiologia , Marrocos , Filogenia , Raízes de Plantas/microbiologia , Prosopis/microbiologia , RNA Ribossômico 16S/genética , Simbiose
15.
Oncogene ; 29(18): 2616-27, 2010 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-20154724

RESUMO

Recent studies have established that amplification of the MET proto-oncogene can cause resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer (NSCLC) cell lines with EGFR-activating mutations. The role of non-amplified MET in EGFR-dependent signaling before TKI resistance, however, is not well understood. Using NSCLC cell lines and transgenic models, we demonstrate here that EGFR activation by either mutation or ligand binding increases MET gene expression and protein levels. Our analysis of 202 NSCLC patient specimens was consistent with these observations: levels of MET were significantly higher in NSCLC with EGFR mutations than in NSCLC with wild-type EGFR. EGFR regulation of MET levels in cell lines occurred through the hypoxia-inducible factor (HIF)-1alpha pathway in a hypoxia-independent manner. This regulation was lost, however, after MET gene amplification or overexpression of a constitutively active form of HIF-1alpha. EGFR- and hypoxia-induced invasiveness of NSCLC cells, but not cell survival, were found to be MET dependent. These findings establish that, absent MET amplification, EGFR signaling can regulate MET levels through HIF-1alpha and that MET is a key downstream mediator of EGFR-induced invasiveness in EGFR-dependent NSCLC cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Neoplasias Pulmonares/patologia , Proteínas Proto-Oncogênicas c-met/fisiologia , Receptores de Fatores de Crescimento/fisiologia , Animais , Hipóxia Celular , Linhagem Celular Tumoral , Receptores ErbB/antagonistas & inibidores , Amplificação de Genes , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/análise , Camundongos , Invasividade Neoplásica , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-met/análise , Proteínas Proto-Oncogênicas c-met/genética , Receptores de Fatores de Crescimento/análise , Receptores de Fatores de Crescimento/genética
16.
Oncogene ; 29(10): 1421-30, 2010 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-19966867

RESUMO

DNA amplifications, leading to the overexpression of oncogenes, are a cardinal feature of lung cancer and directly contribute to its pathogenesis. To uncover such novel alterations, we performed an array-based comparative genomic hybridization survey of 128 non-small-cell lung cancer cell lines and tumors. Prominent among our findings, we identified recurrent high-level amplification at cytoband 22q11.21 in 3% of lung cancer specimens, with another 11% of specimens exhibiting low-level gain spanning that locus. The 22q11.21 amplicon core contained eight named genes, only four of which were overexpressed (by transcript profiling) when amplified. Among these, CRKL encodes an adapter protein functioning in signal transduction, best known as a substrate of the BCR-ABL kinase in chronic myelogenous leukemia. RNA-interference-mediated knockdown of CRKL in lung cancer cell lines with (but not without) amplification led to significantly decreased cell proliferation, cell-cycle progression, cell survival, and cell motility and invasion. In addition, overexpression of CRKL in immortalized human bronchial epithelial cells led to enhanced growth factor-independent cell growth. Our findings indicate that amplification and resultant overexpression of CRKL contribute to diverse oncogenic phenotypes in lung cancer, with implications for targeted therapy, and highlight a role of adapter proteins as primary genetic drivers of tumorigenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Amplificação de Genes , Perfilação da Expressão Gênica , Neoplasias Pulmonares/genética , Proteínas Nucleares/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Cromossomos Humanos Par 22/genética , Hibridização Genômica Comparativa , Humanos , Hibridização in Situ Fluorescente , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/fisiopatologia , Proteínas Nucleares/metabolismo , Proteínas Nucleares/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos , Interferência de RNA
17.
Oncogene ; 27(33): 4615-24, 2008 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-18391978

RESUMO

Chromosomal translocation is the best-characterized genetic mechanism for oncogene activation. However, there are documented examples of activation by alternate mechanisms, for example gene dosage increase, though its prevalence is unclear. Here, we answered the fundamental question of the contribution of DNA amplification as a molecular mechanism driving oncogenesis. Comparing 104 cancer lines representing diverse tissue origins identified genes residing in amplification 'hotspots' and discovered an unexpected frequency of genes activated by this mechanism. The 3431 amplicons identified represent approximately 10 per hematological and approximately 36 per epithelial cancer genome. Many recurrently amplified oncogenes were previously known to be activated only by disease-specific translocations. The 135 hotspots identified contain 538 unique genes and are enriched for proliferation, apoptosis and linage-dependency genes, reflecting functions advantageous to tumor growth. Integrating gene dosage with expression data validated the downstream impact of the novel amplification events in both cell lines and clinical samples. For example, multiple downstream components of the EGFR-family-signaling pathway, including CDK5, AKT1 and SHC1, are overexpressed as a direct result of gene amplification in lung cancer. Our findings suggest that amplification is far more common a mechanism of oncogene activation than previously believed and that specific regions of the genome are hotspots of amplification.


Assuntos
Amplificação de Genes/genética , Dosagem de Genes/genética , Neoplasias Pulmonares/genética , Proteínas Oncogênicas/genética , Oncogenes/genética , Translocação Genética/genética , Animais , Linhagem Celular Tumoral , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Genoma Humano , Humanos , Neoplasias Pulmonares/metabolismo , Proteínas Oncogênicas/metabolismo , Transdução de Sinais/genética
18.
Oncogene ; 27(25): 3635-40, 2008 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-18212743

RESUMO

Lung cancer is a leading cause of cancer death, where the amplification of oncogenes contributes to tumorigenesis. Genomic profiling of 128 lung cancer cell lines and tumors revealed frequent focal DNA amplification at cytoband 14q13.3, a locus not amplified in other tumor types. The smallest region of recurrent amplification spanned the homeobox transcription factor TITF1 (thyroid transcription factor 1; also called NKX2-1), previously linked to normal lung development and function. When amplified, TITF1 exhibited increased expression at both the RNA and protein levels. Small interfering RNA (siRNA)-mediated knockdown of TITF1 in lung cancer cell lines with amplification led to reduced cell proliferation, manifested by both decreased cell-cycle progression and increased apoptosis. Our findings indicate that TITF1 amplification and overexpression contribute to lung cancer cell proliferation rates and survival and implicate TITF1 as a lineage-specific oncogene in lung cancer.


Assuntos
Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Proteínas Nucleares/biossíntese , Fatores de Transcrição/biossíntese , Apoptose , Linhagem Celular Tumoral , Linhagem da Célula , Mapeamento Cromossômico , Genoma Humano , Humanos , Modelos Biológicos , Metástase Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , Oncogenes , RNA Interferente Pequeno/metabolismo , Fator Nuclear 1 de Tireoide
19.
J Nutr Health Aging ; 11(1): 38-48, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17315079

RESUMO

Weight loss, together with psychological and behavioural symptoms and problems of mobility, is one of the principal manifestations of Alzheimer's disease (AD). Weight loss may be associated with protein and energy malnutrition leading to severe complications (alteration of the immune system, muscular atrophy, loss of independence). Various explanations have been proposed such as atrophy of the mesial temporal cortex, biological disturbances, or feeding behaviours; however, none has been proven. Prevention of weight loss in AD is a major issue. It requires regular follow-up and must be an integral part of the care plan. The aim of this article is to review the present state of scientific knowledge on weight loss associated with AD. We will consider four points: the natural history of weight loss, its known etiological factors, its consequences and the various management options.


Assuntos
Doença de Alzheimer/fisiopatologia , Metabolismo Energético/fisiologia , Fenômenos Fisiológicos da Nutrição , Redução de Peso , Córtex Cerebral/patologia , Humanos , Estado Nutricional
20.
Oncogene ; 26(18): 2658-66, 2007 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-17057737

RESUMO

c-Jun N-terminal kinase (JNK) has been reported to either potentiate or inhibit oncogenesis, depending upon the cellular context, but its role in lung neoplasia is unclear. Here we sought to define the role of JNK in lung neoplasia by examining evidence of JNK phosphorylation in non-small-cell lung cancer (NSCLC) biopsy samples and by using genetic and pharmacologic approaches to modulate JNK expression and activity in cultured cells. Immunohistochemical staining for JNK phosphorylation was detected in 114 (45%) of 252 NSCLC biopsy samples and was predominantly nuclear, providing evidence of JNK activation in a subset of NSCLC cases. Introduction of a doxycycline-inducible, constitutively active, mutant mitogen-activated protein kinase kinase 4 (MKK4) into the human bronchial epithelial cell lines BEAS-2B and HB56B increased the cells' proliferation, migration, invasion and clonogenicity. Depletion of JNK in MKK4 mutant-transformed BEAS-2B cells by introduction of JNK1/2 short hairpin RNA reversed the transformed phenotype, indicating that JNK activation is oncogenic and MKK4 confers neoplastic properties in these cells. The proliferation of NSCLC cell lines HCC827 and H2009, in which JNK and its substrate c-Jun are constitutively phosphorylated, was inhibited by SP600125, a JNK kinase inhibitor. We conclude that JNK is activated in a subset of NSCLC biopsy samples and promotes oncogenesis in the bronchial epithelium, suggesting that strategies to inhibit the JNK pathway should be considered for the prevention and treatment of NSCLC.


Assuntos
Brônquios/metabolismo , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Transformação Celular Neoplásica , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Brônquios/citologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Movimento Celular , Proliferação de Células , Células Cultivadas , Ativação Enzimática , Células Epiteliais/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , MAP Quinase Quinase 4/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-jun/genética , Transdução de Sinais
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