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1.
Sleep Med ; 73: 202-207, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32858331

RESUMO

Data regarding the possible relationship of insomnia and EDS with mortality are inconclusive. The aim of this study was to investigate the association between these sleep complaints and the risk of long-term (20 years) all-cause mortality in older adults. Between April 2000 and March 2001, 750 subjects aged 65 years and older, who resided in the seventh district of Udine, were recruited. Data on sociodemographic characteristics, past medical history, and pharmacological treatment were collected. Dementia was diagnosed using a comprehensive neurological and neuroradiological assessment. Older adults were interviewed by neuropsychologists trained in sleep disturbances in order to assess the presence of sleep complaints. Vital status was followed over 20 years until March 2020. Older male adults affected by insomnia and EDS were significantly more likely to die over the follow-up period. Indeed, males reporting poor sleep and daytime somnolence had a 60% and 48% higher chance of dying than subjects who were not affected by these sleep complaints, respectively. The HR was attenuated after adjusting for confounding variables among insomniacs, whereas that of somnolent men strengthened. Differently from men, insomnia and EDS did not have any impact on mortality in older women. In conclusion, older male adults affected by insomnia and EDS had a significant increased risk of mortality, which is independent of cancer, depression, dementia, cardiovascular diseases, and sleeping pill use.


Assuntos
Distúrbios do Sono por Sonolência Excessiva , Distúrbios do Início e da Manutenção do Sono , Idoso , Distúrbios do Sono por Sonolência Excessiva/epidemiologia , Feminino , Humanos , Masculino , Sono , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Sonolência , Inquéritos e Questionários
2.
Br J Cancer ; 113(2): 290-8, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-26057454

RESUMO

BACKGROUND: Breast cancer clinical outcome is affected by tumor molecular features, and the identification of subtype-specific prognostic biomarkers is relevant for breast cancer translational research. Gene expression signatures proved to be able to complement prognostic information provided by classical clinico-pathological features. Recently, microRNAs (miRNAs) have been causally linked to tumorigenesis and cancer progression and have been associated with patient outcome, also in breast cancer. METHODS: MicroRNAs associated with the development of distant metastasis were identified in a cohort of 92 ESR1+/ERBB2- lymph node-negative breast cancers from patients not receiving adjuvant treatment. Results were confirmed and further investigated in a total of 1246 miRNA and gene expression profiles of the Molecular Taxonomy of Breast Cancer International Consortium data set. Moderated t-test, univariable and multivariable Cox regression models were used for statistical analyses. RESULTS: miR-30e* was identified as independent protective prognostic factor in lymph node-negative untreated patients with ESR1+/ERBB2- tumours and retained a significant association with a good prognosis in treated patients with the same tumor subtype as well as in the ERBB2+ subtype, but not in ESR1-/ERBB2- tumours. CONCLUSIONS: We highlighted a relevant and subtype-specific role in breast cancer for miR-30e* and demonstrated that adding miRNA markers to gene signatures and clinico-pathological features can help for a better prognostication.


Assuntos
Neoplasias da Mama/genética , MicroRNAs/fisiologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Receptor alfa de Estrogênio/análise , Feminino , Humanos , Metástase Linfática , MicroRNAs/análise , Prognóstico , Modelos de Riscos Proporcionais , Receptor ErbB-2/análise , Transcriptoma
3.
Sleep Med ; 11(4): 372-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20219426

RESUMO

OBJECTIVE: The occurrence of dementia among the elderly has been associated with several, often not modifiable, risk factors. Recent epidemiological studies focused their interest on a possible association between cognitive decline and sleep, a potentially modifiable risk factor. Due to controversial results and limitations of the previous studies, we decided to reexamine the relationship between disturbed sleep and cognitive impairment in the elderly. METHODS: Seven hundred fifty subjects aged 65years or older were recruited. The Mini-Mental State Examination (MMSE) and the Global Deterioration Scale (GDS) scores were used to evaluate the severity of cognitive decline. Diagnosis of dementia was made by means of the DSM-IV criteria. The older adults were interviewed in order to assess the presence of several sleep complaints (insomnia, snoring and/or witnessed sleep apneas, restlessness and/or leg jerks, sleepwalking and nightmares). Excessive daytime sleepiness was evaluated by means of a validated questionnaire. The principal caregiver of each older adult took part in the interview, providing the information if the subject was unable to answer because of mental impairment. RESULTS: Eighty-six individuals were diagnosed as demented; a large part of them (47.8%), in particular, were recognized as being affected by Alzheimer's disease. The prevalence of each sleep complaint in the older adults was as follows: insomnia 84.7%, snoring and/or witnessed sleep apneas 26.2%, restlessness and/or jerks in the legs 25.7%, sleepwalking 0.5%, nightmares 6.4% and daytime somnolence 30.6%. Among sleep disturbances, excessive daytime sleepiness was independently associated with the presence of dementia in the elderly. In addition, the frequency of excessive daytime sleepiness increased progressively across the different categories of cognitive decline, as measured by means of MMSE and GDS scores. CONCLUSIONS: Insomnia, the most common sleep complaint in our sample, was not associated with the presence of cognitive decline. As opposed to insomnia, excessive daytime sleepiness was significantly related to dementia. Further studies are needed in order to investigate the direction of this association and to evaluate the possible role of daytime somnolence as an early marker of neurodegenerative disease, particularly Alzheimer's disease, in some older adults.


Assuntos
Transtornos Cognitivos/epidemiologia , Demência/diagnóstico , Demência/epidemiologia , Distúrbios do Sono por Sonolência Excessiva/diagnóstico , Distúrbios do Sono por Sonolência Excessiva/epidemiologia , Idoso , Transtornos Cognitivos/diagnóstico , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Vigilância da População/métodos , Prevalência , Índice de Gravidade de Doença
4.
Oncogene ; 29(16): 2449-56, 2010 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-20118982

RESUMO

Cutaneous malignant melanoma is considered one of the most deadly human cancers, based on both its penchant for metastatic spread and its typical resistance to currently available therapy. Long known to harbor oncogenic NRAS mutations, melanomas were more recently reported to be frequent bearers of activating mutations in BRAF, one of the effectors situated downstream of wild-type NRAS. NRAS and BRAF mutations are rarely found in the same melanoma, suggesting that they may possess important overlapping oncogenic activities. Here, we compare and contrast the oncogenic roles of the three major NRas downstream effectors, Raf, phosphatidylinositol 3-kinase (PI3K) and Ral guanine exchange factor (RalGEF), using genetically engineered Arf-deficient immortalized mouse melanocytes as a model system. Although no single downstream pathway could recapitulate all of the consequences of oncogenic NRas expression, our data indicate a prominent role for BRaf and PI3K in melanocyte senescence and invasiveness, respectively. More surprisingly, we discovered that constitutive RalGEF activation had a major impact on several malignant phenotypes, particularly anchorage-independent growth, indicating that this often overlooked pathway should be more carefully evaluated as a possible therapeutic target.


Assuntos
Transformação Celular Neoplásica , Genes ras/fisiologia , Melanoma/etiologia , Fator ral de Troca do Nucleotídeo Guanina/fisiologia , Animais , Inibidor p16 de Quinase Dependente de Ciclina/fisiologia , Camundongos , PTEN Fosfo-Hidrolase/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas B-raf/fisiologia , Proteínas Proto-Oncogênicas c-raf/fisiologia , Transdução de Sinais
6.
Sleep Med ; 10(1): 26-34, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18207453

RESUMO

BACKGROUND: Patients with multiple sclerosis (MS) report sleep disturbances more frequently than the general population. Besides specific sleep disturbances, many other conditions could impair nocturnal rest in this population. In addition, information regarding the role of disrupted sleep on quality of life (QoL) in MS patients is lacking. This study was performed to bridge this gap. METHODS: A total of 120 patients with MS were enrolled into the study. Demographic, socioeconomic and clinical characteristics (clinical course and duration of MS, EDSS score, therapeutic information, presence of pain, presence of sexual and/or bladder dysfunction, localization of demyelinating plaques, and presence of anxiety and depression) were collected. The Pittsburgh Sleep Quality Index (PSQI), the Charlson Comorbidity Index (CCI) and the Italian version of the 36-item Short Form (SF-36) were used to assess quality of sleep, comorbidity and QoL, respectively. RESULTS: Nearly half (47.5%) of MS patients were classified as "poor sleepers," having significantly higher EDSS (3.1+/-1.4 vs. 2.3+/-1.4, p=0.009) and CCI scores (0.19+/-0.4 vs. 0.03+/-0.2, p=0.009) than "good sleepers." In addition, pain due to MS was more common among "poor sleepers" (33.3% vs. 17.7%, p=0.05). Scores for each domain of the SF-36, and the mental component summary (MCS) and physical component summary (PCS) scores were significantly lower in poor sleepers than in good sleepers (p<0.001 for each score). Of the different variables associated with MCS, the only independent predictors of mental status were: presence of sexual and/or bladder dysfunction and global PSQI score. The independent predictors for physical status (PCS) were age, EDSS score and global PSQI score. CONCLUSIONS: Poor sleep is common in patients with MS, representing an independent predictor of QoL. Patients with MS who are poor sleepers should receive immediate assessment and treatment, bearing in mind that, in addition to specific sleep disturbances, other clinical conditions (both related and unrelated to MS) can disrupt nocturnal sleep.


Assuntos
Esclerose Múltipla/epidemiologia , Esclerose Múltipla/psicologia , Qualidade de Vida , Transtornos do Sono-Vigília/epidemiologia , Transtornos do Sono-Vigília/psicologia , Adulto , Ansiedade/epidemiologia , Comorbidade , Depressão/epidemiologia , Avaliação da Deficiência , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência
8.
Oncogene ; 27(40): 5373-84, 2008 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-18504437

RESUMO

Metastasis is the primary cause of death in patients with breast cancer. Overexpression of c-myc in humans correlates with metastases, but transgenic mice only show low rates of micrometastases. We have generated transgenic mice that overexpress both c-myc and vascular endothelial growth factor (VEGF) (Myc/VEGF) in the mammary gland, which develop high rates of pulmonary macrometastases. Gene expression profiling revealed a set of deregulated genes in Myc/VEGF tumors compared to Myc tumors associated with the increased metastatic phenotype. Cross-comparisons between this set of genes with a human breast cancer lung metastasis gene signature identified five common targets: tenascin-C(TNC), matrix metalloprotease-2, collagen-6-A1, mannosidase-alpha-1A and HLA-DPA1. Signaling blockade or knockdown of TNC in MDA-MB-435 cells resulted in a significant impairment of cell migration and anchorage-independent cell proliferation. Mice injected with clonal MDA-MB-435 cells with reduced expression of TNC demonstrated a significant decrease (P<0.05) in (1) primary tumor growth; (2) tumor relapse after surgical removal of the primary tumor and (3) incidence of lung metastasis. Our results demonstrate that VEGF induces complex alterations in tissue architecture and gene expression. The TNC signaling pathway plays an important role in mammary tumor growth and metastases, suggesting that TNC may be a relevant target for therapy against metastatic breast cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Pulmonares/secundário , Neoplasias Mamárias Experimentais/patologia , Proteínas Proto-Oncogênicas c-myc/fisiologia , Tenascina/farmacologia , Fator A de Crescimento do Endotélio Vascular/fisiologia , Animais , Biomarcadores Tumorais/genética , Northern Blotting , Western Blotting , Adesão Celular , Movimento Celular , Proliferação de Células , Perfilação da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/prevenção & controle , Neoplasias Mamárias Experimentais/genética , Camundongos , Camundongos Transgênicos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tenascina/antagonistas & inibidores , Tenascina/genética , Células Tumorais Cultivadas , Ensaio Tumoral de Célula-Tronco
9.
Clin Pharmacol Ther ; 84(1): 63-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17987049

RESUMO

Emerging evidence suggests that psychosis in persons with Alzheimer's disease (AD) may be linked to the cholinergic deficit associated with the disease. This study sought to evaluate whether anticholinergic (ACH) drugs could be a risk factor for psychosis onset. A total of 230 patients affected with probable AD were recruited. Data on behavioral and psychological symptoms were collected using the Neuropsychiatric Inventory, and diagnosis of psychosis was performed. Patients were divided into those who used ACH drugs and those who used non-ACH drugs. Those using ACH drugs (18.3%) were more likely to have psychosis than those using non-ACH drugs (odds ratio (OR)=2.52; 95% confidence interval (CI), 1.27-5.00); this association remained significant even after adjusting for potential confounding variables (OR=2.13; 95% CI, 1.03-4.43). Our data suggest that patients with AD are frequently treated with ACH drugs and that ACH drug intake should be regarded as a potential risk factor for psychosis.


Assuntos
Doença de Alzheimer/psicologia , Antagonistas Colinérgicos/efeitos adversos , Psicoses Induzidas por Substâncias/psicologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicoses Induzidas por Substâncias/complicações , Fatores de Risco
10.
Neurol Sci ; 28 Suppl 1: S37-46, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17235430

RESUMO

Restless legs syndrome (RLS) is a sensorimotor disorder characterised by a complaint of an almost irresistible urge to move the legs. RLS is diagnosed clinically by means of the four essential criteria of the International Restless Legs Syndrome Study Group. In doubtful cases, neurophysiological examinations, such as polysomnography and/or a suggested immobilisation test, can be performed to confirm a clinical suspicion of RLS. Several other conditions may present sensorimotor complaints with features similar to RLS; a careful sleep history is required to avoid a misdiagnosis. Three different scales have been validated to assess the severity of RLS. In the general population, RLS prevalence ranges from 0.1% to 11.5%, with a high number of patients affected by a primary form of the sleep disturbance (70%-80%). However, several clinical conditions have been associated with RLS, such as iron deficiency, uraemia, pregnancy and polyneuropathy. Furthermore, recent studies show that RLS may be associated also to type 2 diabetes mellitus and to multiple sclerosis. RLS has a negative impact on sleep, cognitive functions, quality of life and mental status. Higher awareness of RLS among physicians is required; it remains an underdiagnosed clinical condition.

12.
J Hand Surg Eur Vol ; 32(1): 98-101, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17034910

RESUMO

A vascularised bone segment of the distal radius was harvested as a distally based flap to treat segmental metacarpal bone loss in three patients. One reconstruction followed resection of a giant cell tumour excision and the other two were to replace traumatic bone loss. The bone defects were in the second metacarpal in two cases and in the second and third metacarpal in one case and included three shaft and one distal metacarpal reconstruction. The mean length of the metacarpal defects was 6 cm. All of the flaps survived and no complications occurred at the donor site. Clinical and radiological union was established in all cases after an average of 3 months.


Assuntos
Neoplasias Ósseas/cirurgia , Transplante Ósseo , Fraturas Expostas/cirurgia , Tumor de Células Gigantes do Osso/cirurgia , Traumatismos da Mão/cirurgia , Ossos Metacarpais/lesões , Ossos Metacarpais/cirurgia , Microcirurgia , Retalhos Cirúrgicos/irrigação sanguínea , Ferimentos por Arma de Fogo/cirurgia , Adulto , Neoplasias Ósseas/diagnóstico por imagem , Placas Ósseas , Feminino , Fraturas Expostas/diagnóstico por imagem , Tumor de Células Gigantes do Osso/diagnóstico por imagem , Traumatismos da Mão/diagnóstico por imagem , Força da Mão/fisiologia , Humanos , Masculino , Ossos Metacarpais/diagnóstico por imagem , Pessoa de Meia-Idade , Artéria Radial/cirurgia , Radiografia , Lesões dos Tecidos Moles/diagnóstico por imagem , Lesões dos Tecidos Moles/cirurgia , Ferimentos por Arma de Fogo/diagnóstico por imagem
13.
Neurol Res ; 27(4): 433-5, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15949243

RESUMO

OBJECTIVES: Volatile anesthetics are thought to impair cerebral autoregulation more than i.v. anesthetics. However, few comparative studies have been carried out in humans. The aim of our study was to evaluate the differences in cerebral hemodynamic changes after introduction of isoflurane (a volatile anesthetic) and propofol (an i.v. anesthetic). METHODS: Eighteen consecutive patients submitted to laparoscopic cholecystectomy were selected. After the induction, anesthesia was maintained by isoflurane (one minimum alveolar anesthetic concentration) during the first part of the surgical operation, and then by propofol (5 mg/kg/hour i.v.). Ventilation was adjusted to maintain a constant end-tidal CO(2). Middle artery flow velocity was assessed by means of transcranial Doppler ultrasonography. Arterial blood pressure, heart rate (HR), capnometry, pulse oxymetry, inspired fraction of O(2), and body temperature, were monitored. RESULTS: Cerebral artery velocity, HR, and mean arterial pressure all significantly increased from baseline after the introduction of isoflurane (p<0.05); the HR and mean arterial blood pressure showed no significant difference between the isoflurane and propofol phases. Isoflurane anesthesia induced a significant increase in cerebral blood velocity. Propofol introduction led to a significant decrease in cerebral artery velocity (p<0.05). CONCLUSIONS: Propofol but not isoflurane decreased cerebral blood velocity thus restoring cerebral autoregulation and the coupling between cerebral blood flow and cerebral metabolism.


Assuntos
Anestésicos Inalatórios/farmacologia , Anestésicos Intravenosos/farmacologia , Hemodinâmica/efeitos dos fármacos , Isoflurano/farmacologia , Propofol/farmacologia , Adulto , Idoso , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Circulação Cerebrovascular/efeitos dos fármacos , Colecistectomia Laparoscópica/métodos , Estudos de Avaliação como Assunto , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia Doppler Transcraniana/métodos
14.
G Chir ; 23(3): 75-8, 2002 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-12109228

RESUMO

The Authors report a very rare case of clear cell renal cancer associated with sarcoidosis, incidentally discovered in a 39 year-old man, admitted for a not correlated pathology (multiple left rib fractures due to automobile crash). Problems related to a proper assessment of sarcoidosis are discussed as well as potential arising of a neoplasm during the entire follow-up period: for that, it must always be complete and accurate.


Assuntos
Adenocarcinoma de Células Claras/complicações , Adenocarcinoma de Células Claras/diagnóstico , Neoplasias Renais/complicações , Neoplasias Renais/diagnóstico , Sarcoidose/complicações , Sarcoidose/diagnóstico , Adulto , Diagnóstico Diferencial , Humanos , Masculino
15.
FEBS Lett ; 509(1): 95-100, 2001 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-11734213

RESUMO

The effect of hepatocyte growth factor/scatter factor (HGF/SF) during wound healing in the skin was investigated, using HGF/SF-overexpressing transgenic mouse model. Histological analysis of HGF/SF transgenic mouse excisional wound sites revealed increased granulation tissue with marked vascularization. Northern blot analysis demonstrated that, relative to control, vascular endothelial growth factor (VEGF) expression in transgenic skin was significantly higher at baseline and was robustly up-regulated during wound healing. Elevated levels of VEGF protein were detected immunohistochemically, predominantly in endothelial cells and fibroblasts within the granulation tissue of HGF/SF transgenic skin. Serum levels of VEGF were also elevated in HGF/SF transgenic mice. Thus, results from our study suggest that HGF/SF has a significant effect on vascularization and granulation tissue formation during wound healing in vivo, involving with induction of VEGF.


Assuntos
Fatores de Crescimento Endotelial/biossíntese , Fator de Crescimento de Hepatócito/biossíntese , Fator de Crescimento de Hepatócito/fisiologia , Linfocinas/biossíntese , Neovascularização Patológica , Animais , Northern Blotting , DNA Complementar/metabolismo , Fatores de Crescimento Endotelial/sangue , Endotélio/metabolismo , Fibroblastos/metabolismo , Imuno-Histoquímica , Linfocinas/sangue , Camundongos , Camundongos Transgênicos , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular , Cicatrização
16.
Nature ; 413(6853): 271-2, 2001 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-11565020

RESUMO

Retrospective epidemiological data have indicated that cutaneous malignant melanoma may arise as a consequence of intense, intermittent exposure of the skin to ultraviolet radiation, particularly in children, rather than from the cumulative lifetime exposure that is associated with other forms of skin cancer. Here we use a genetically engineered mouse model to show that a single dose of burning ultraviolet radiation to neonates, but not adults, is necessary and sufficient to induce tumours with high penetrance which are reminiscent of human melanoma. Our results provide experimental support for epidemiological evidence that childhood sunburn poses a significant risk of developing this potentially fatal disease.


Assuntos
Melanoma Experimental/etiologia , Neoplasias Induzidas por Radiação/etiologia , Neoplasias Cutâneas/etiologia , Queimadura Solar/complicações , Animais , Animais Recém-Nascidos , Criança , Modelos Animais de Doenças , Fator de Crescimento de Hepatócito/genética , Humanos , Camundongos , Camundongos Transgênicos , Raios Ultravioleta
17.
G Chir ; 22(5): 171-6, 2001 May.
Artigo em Italiano | MEDLINE | ID: mdl-11443841

RESUMO

The Authors report their experience matured during the last decade in the Institute of III Surgical Clinic of the University "La Sapienza" in Rome, relatively to 174 patients operated of splenectomy of which 8 for not parassitair benign cystic pathology. After the nosologic organization of the varied types of cystics splenopaty is examined the different symptomatology and is discussed the different treatment.


Assuntos
Cistos , Esplenopatias , Adulto , Idoso , Cistos/diagnóstico , Cistos/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esplenopatias/diagnóstico , Esplenopatias/cirurgia
18.
Semin Cancer Biol ; 11(3): 201-18, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11407945

RESUMO

Pancreatic cancer is among the leading causes of cancer death. Although a genetic profile for pancreatic cancer is emerging, many biological aspects of this disease are poorly understood. Indeed, fundamental questions regarding progenitor cell lineages, host stromal milieu, and the role of specific genetic alterations in tumor progression remain unresolved. A mouse model engineered with signature mutations would provide a powerful ally in the study of pancreatic cancer biology and may guide improved prognostic assessment and treatment for the human disease. In this review, we discuss the molecular basis for normal pancreatic development and the genetics of human pancreatic adenocarcinoma in the hope of charting a course for the development of a faithful mouse model for this lethal cancer.


Assuntos
Adenocarcinoma/genética , Modelos Animais de Doenças , Neoplasias Pancreáticas/genética , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Animais , Linhagem da Célula , Genes Supressores de Tumor , Camundongos , Camundongos Transgênicos , Mutação , Pâncreas/crescimento & desenvolvimento , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/patologia
19.
Semin Cancer Biol ; 11(3): 261-8, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11407950

RESUMO

The frequent loss of the INK4a/ARF locus, encoding for both p16(INK4a)and p19(ARF)in human melanoma, raises the question as to which INK4a/ARF gene product functions to suppress melanoma-genesis in vivo. Studies in the mouse have shown that activated RAS mutation can cooperate with INK4a(Delta 2/3)deficiency (null for both p16(INK4a)and p19(ARF)) to promote development of melanoma, and these melanomas retain wild-type p53. Given the functional link between p19(ARF)and p53, we have now shown that activated RAS can also cooperate with p53 deficiency to produce melanoma in the mouse. Moreover, genome-wide analysis of RAS-induced p53 mutant melanomas reveals alterations of key components governing RB-regulated G1/S transition, such as c-Myc. These experimental findings suggest that both RB and p53 pathways function to suppress melanocyte transformation in vivo in the mouse.


Assuntos
Melanoma/genética , Proteínas dos Microtúbulos , Animais , Inibidor p16 de Quinase Dependente de Ciclina/genética , Modelos Animais de Doenças , Deleção de Genes , Genes Supressores de Tumor , Humanos , Camundongos , Fosfoproteínas/genética , Estatmina , Proteína Supressora de Tumor p53/genética
20.
Carcinogenesis ; 22(6): 975-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11375907

RESUMO

The mechanisms underlying peroxisome proliferator-induced hepatocarcinogenesis are not understood. Because of the uncertainty of human cancer risk associated with peroxisome proliferators, delineating the mechanisms of carcinogenesis by these agents is of great interest. Alterations in liver growth factors were postulated to contribute to the carcinogenic effect of peroxisome proliferators. Administration of these compounds to rodents results in down-regulation of hepatocyte growth factor (HGF) and supplementing culture medium with HGF is reported to suppress cell proliferation of preneoplastic and neoplastic cells from WY-14,643-treated livers. Combined, these observations suggest that reduced levels of hepatic HGF contribute to the mechanisms underlying peroxisome proliferator-induced hepatocarcinogenesis. To determine if HGF can prevent the effects of peroxisome proliferators in liver, the short-term influence of WY-14,643 in two different lines of HGF transgenic mice was examined. Mice were fed either a control diet or one containing 0.1% WY-14-643 for one week. Hepatomegaly was found in both HGF transgenic mouse lines fed WY-14,643 compared with controls. Additionally, hepatic expression of typical mRNA markers of peroxisome proliferation including those encoding peroxisomal fatty acid metabolizing enzymes and cell cycle control proteins were all significantly elevated in HGF transgenic mice fed WY-14,643 compared with controls. Down-regulation of HGF was found to be dependent on PPARalpha since lower levels of HGF mRNA and protein were observed in wild-type mice fed WY-14,643 for 1 week and not in similarly treated PPARalpha-null mice. These results demonstrate that the early increase in hepatic mRNAs associated with peroxisome and cell proliferation induced by WY-14,643 treatment can not be prevented by overexpression of HGF in vivo.


Assuntos
Fator de Crescimento de Hepatócito/fisiologia , Hepatócitos/efeitos dos fármacos , Proliferadores de Peroxissomos/toxicidade , Animais , Carcinógenos/toxicidade , Divisão Celular/efeitos dos fármacos , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/metabolismo , Hepatócitos/citologia , Humanos , Neoplasias Hepáticas Experimentais/induzido quimicamente , Camundongos , Camundongos Transgênicos , Pirimidinas/toxicidade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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