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1.
Oncogene ; 32(14): 1843-53, 2013 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-22614007

RESUMO

Prostate cancer is one of the leading causes of cancer-related death in men. Despite significant advances in prostate cancer diagnosis and management, the molecular events involved in the transformation of normal prostate cells into cancer cells have not been fully understood. It is generally accepted that prostate cancer derives from the basal compartment while expressing luminal markers. We investigated whether downregulation of the basal protein B-cell translocation gene 2 (BTG2) is implicated in prostate cancer transformation and progression. Here we show that BTG2 loss can shift normal prostate basal cells towards luminal markers expression, a phenotype also accompanied by the appearance of epithelial-mesenchymal transition (EMT) traits. We also show that the overexpression of microRNA (miR)-21 suppresses BTG2 levels and promotes the acquisition of luminal markers and EMT in prostate cells. Furthermore, by using an innovative lentiviral vector able to compete with endogenous mRNA through the overexpression of the 3'-untranslated region of BTG2, we demonstrate that in prostate tumor cells, the levels of luminal and EMT markers can be reduced by derepression of BTG2 from microRNA-mediated control. Finally, we show that the loss of BTG2 expression confers to non-tumorigenic prostate cells ability to grow in an orthotopic murine model, thus demonstrating the central role of BTG2 downregulaton in prostate cancer biology.


Assuntos
Biomarcadores Tumorais/genética , Transformação Celular Neoplásica/patologia , Transição Epitelial-Mesenquimal , Proteínas Imediatamente Precoces/metabolismo , MicroRNAs/genética , Próstata/patologia , Neoplasias da Próstata/patologia , Proteínas Supressoras de Tumor/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/metabolismo , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células , Células Cultivadas , Citometria de Fluxo , Imunofluorescência , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Imediatamente Precoces/antagonistas & inibidores , Proteínas Imediatamente Precoces/genética , Masculino , Camundongos , Próstata/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Supressoras de Tumor/antagonistas & inibidores , Proteínas Supressoras de Tumor/genética
2.
Oncogene ; 30(41): 4231-42, 2011 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-21532615

RESUMO

The interaction between cancer cells and microenvironment has a critical role in tumor development and progression. Although microRNAs regulate all the major biological mechanisms, their influence on tumor microenvironment is largely unexplored. Here, we investigate the role of microRNAs in the tumor-supportive capacity of stromal cells. We demonstrated that miR-15 and miR-16 are downregulated in fibroblasts surrounding the prostate tumors of the majority of 23 patients analyzed. Such downregulation of miR-15 and miR-16 in cancer-associated fibroblasts (CAFs) promoted tumor growth and progression through the reduced post-transcriptional repression of Fgf-2 and its receptor Fgfr1, which act on both stromal and tumor cells to enhance cancer cell survival, proliferation and migration. Moreover, reconstitution of miR-15 and miR-16 impaired considerably the tumor-supportive capability of stromal cells in vitro and in vivo. Our data suggest a molecular circuitry in which miR-15 and miR-16 and their correlated targets cooperate to promote tumor expansion and invasiveness through the concurrent activity on stromal and cancer cells, thus providing further support to the development of therapies aimed at reconstituting miR-15 and miR-16 in advanced prostate cancer.


Assuntos
Fibroblastos/metabolismo , MicroRNAs/genética , Neoplasias da Próstata/genética , Microambiente Tumoral/genética , Idoso , Idoso de 80 Anos ou mais , Animais , Western Blotting , Linhagem Celular Tumoral , Regulação para Baixo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fibroblastos/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Fosforilação , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Heterólogo
4.
Oncogene ; 27(34): 4657-65, 2008 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-18408767

RESUMO

Carcinoma is an altered state of tissue differentiation in which epithelial cells no longer respond to cues that keep them in their proper position. A break down in these cues has disastrous consequences not only in cancer but also in embryonic development when cells of various lineages must organize into discrete entities to form a body plan. Paraxial protocadherin (PAPC) is an adhesion protein with six cadherin repeats that organizes the formation and polarity of developing cellular structures in frog, fish and mouse embryos. Here we show that protocadherin-8 (PCDH8), the human ortholog of PAPC, is inactivated through either mutation or epigenetic silencing in a high fraction of breast carcinomas. Loss of PCDH8 expression is associated with loss of heterozygosity, partial promoter methylation, and increased proliferation. Complementation of mutant tumor cell line HCC2218 with wild-type PCDH8 inhibited its growth. Two tumor mutants, E146K and R343H, were defective for inhibition of cell growth and migration. Surprisingly, the E146K mutant transformed the human mammary epithelial cell line MCF10A and sustained the expression of cyclin D1 and MYC without epidermal growth factor. We propose that loss of PCDH8 promotes oncogenesis in epithelial human cancers by disrupting cell-cell communication dedicated to tissue organization and repression of mitogenic signaling.


Assuntos
Neoplasias da Mama/genética , Caderinas/fisiologia , Genes Supressores de Tumor/fisiologia , Animais , Sequência de Bases , Caderinas/genética , Caderinas/metabolismo , Comunicação Celular/genética , Movimento Celular/genética , Transformação Celular Neoplásica/genética , Metilação de DNA , Análise Mutacional de DNA , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Humanos , Glândulas Mamárias Humanas/metabolismo , Camundongos , Mutação , Regiões Promotoras Genéticas , Protocaderinas , Homologia de Sequência do Ácido Nucleico , Células Tumorais Cultivadas
5.
Endoscopy ; 39(12): 1086-91, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17701854

RESUMO

BACKGROUND AND STUDY AIMS: In patients with Barrett's esophagus (BE), targeted endoscopic mucosal resection (EMR) of visible lesions of high grade dysplasia (HGD) or intramucosal adenocarcinoma (IMC) is effective, but carries the risk of leaving in place synchronous lesions and Barrett's epithelium with the potential for recurrent disease. We evaluated the safety and long-term efficacy of complete Barrett's eradication EMR (CBE-EMR) for the treatment of patients with HGD or IMC, independently of the presence of macroscopically visible lesions or surgical risk. PATIENTS AND METHODS: 26 consecutive patients with BE and HGD or IMC underwent CBE-EMRs, which were performed with the endoscopic cap suction method and/or a 2.3-mm monofilament mucosectomy snare. Endoscopic follow up after completion of resection was carried out to assess the rate of residual or recurrent BE with or without HGD or IMC. RESULTS: 24 patients completed the study. They underwent a total of 44 EMR sessions with a median of 3 pieces (range 1-8) removed per session. Two patients with immediate bleeding were successfully managed endoscopically. Three patients developed an early esophageal stricture that was completely resolved with a single endoscopic dilation. After a median follow-up of 28 months (range 15-51 months), persistent endoscopic and histologic eradication of BE was demonstrated in 21 patients (87.5 %). In two patients, Barrett's epithelium was detected beneath the neosquamous epithelium 3 months after completion of the resection. In the remaining patient, IMC was found in a nodule seen and removed by EMR at 12-month surveillance endoscopy. CONCLUSIONS: CBE-EMR is a safe and highly effective long-term treatment that should be offered to all patients with Barrett's esophagus with HGD and IMC.


Assuntos
Adenocarcinoma/cirurgia , Carcinoma/cirurgia , Neoplasias Esofágicas/cirurgia , Esofagoscopia/métodos , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Esôfago de Barrett/mortalidade , Esôfago de Barrett/patologia , Esôfago de Barrett/cirurgia , Carcinoma/mortalidade , Carcinoma/patologia , Neoplasias Esofágicas/patologia , Esofagectomia/métodos , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Mucosa/patologia , Mucosa/cirurgia , Estadiamento de Neoplasias , Estudos Retrospectivos , Medição de Risco , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
6.
Oncol Rep ; 8(6): 1351-3, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11605064

RESUMO

Serum concentrations of prolactin, a trophic hormone produced by the pituitary gland, have been shown to be raised in certain group of patients with cancer. Prolactin was detected in 0-20% of the colon cancer by immunohistochemistry and in plasma in 6-53% of the patients. These conflicting results do not support the hypothesis of an ectopic prolactin production by colon carcinoma. The aim of this study was to confirm the reported incidence of hyper-prolactinemia in colorectal cancer and to find further evidence for an ectopic prolactin production by the tumor. Thirty consecutive patients with colon carcinoma were studied. Before surgery all the patients underwent blood sample collection to assay plasma prolactin levels. All patients underwent colectomy. All the neoplastic specimens were tested with antiprolactin antibody. In none of the patients were significantly high preoperative levels of plasma prolactin found. Prolactin immunostaining was not identified in any of the tumor specimens. We could not confirm previous reports of frequent hyperprolactinemia in patients with cancer. This is the first report in which the incidence of both hyperprolactinemia and prolactin positive immunostaining was 0%. Our study was unable to demonstrate the synthesis of prolactin by colorectal cancers. The tumor is unlikely to be the source of hormone production. Our results suggest that circulating prolactin levels cannot be used as prognostic marker in patients with colon cancer.


Assuntos
Neoplasias do Colo/metabolismo , Prolactina/metabolismo , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Neoplasias do Colo/sangue , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/patologia , Feminino , Humanos , Hiperprolactinemia/etiologia , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Prognóstico , Prolactina/sangue
7.
Anticancer Res ; 21(2B): 1401-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11396222

RESUMO

Ten specimens of adrenal cyst resected during the period 1984-1999 were re-examined. Thorough examination of multiple sections and the use of immunohistochemistry allowed to change the recorded diagnosis in 8 cases: three epithelial cysts and five pseudocysts were redefined as endothelial cysts. All 10 cysts were of the endothelial type. A synthetic review of the current knowledge about the pathogenesis, the classification and the clinical aspects of this rare disease is presented.


Assuntos
Doenças das Glândulas Suprarrenais/patologia , Cistos/patologia , Doenças das Glândulas Suprarrenais/classificação , Doenças das Glândulas Suprarrenais/metabolismo , Adulto , Idoso , Cistos/classificação , Cistos/metabolismo , Feminino , Humanos , Masculino
9.
Surg Today ; 31(10): 928-31, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11759893

RESUMO

We describe herein the case of a heterotopic pancreas that caused stenosis in the second portion of the duodenum. A 46-year-old man presented with upper abdominal pain and a 12-month history of intermittent vomiting. There was no history of melena, hematochezia, hematemesis, clay-colored stools, jaundice, or hepatitis and he did not describe any food dyscrasias, although fatty foods and alcohol seemed to make the symptoms worse. No specific medication or change in position relieved the pain. An initial diagnosis of chronic pancreatitis with multiple pseudocysts was made on the basis of elevated serum amylase and lipase levels, and abdominal ultrasonography and computed tomography (CT) findings. Medical treatment with octreotide was given for 8 weeks, but without any marked effect. Double-contrast barium examination and esophagogastroduodenoscopy were not diagnostic. Magnetic resonance (MR) cholangiopancreatography revealed findings indicative of cystic dystrophy of a heterotopic pancreas (CDHP), and an endoscopy supported this diagnosis. A pancreatoduodenectomy was performed and pathological examination confirmed a diagnosis of CDHP. In our opinion, MR cholangiopancreatography is the diagnostic tool of choice when CDHP is suspected.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/métodos , Coristoma/diagnóstico , Duodenopatias/diagnóstico , Imageamento por Ressonância Magnética , Pâncreas , Humanos , Masculino , Pessoa de Meia-Idade
10.
J Exp Clin Cancer Res ; 19(2): 225-33, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10965823

RESUMO

The aim of this study was to investigate the immunohistochemical expression of epidermal growth factor receptor (EGFR), mucin-1 (MUC-1) and mucin-2 (MUC-2) proteins in primary bladder carcinomas and to compare EGFR and MUC staining patterns with the histological findings, grade and stage of bladder carcinoma. Fifty-six surgical specimens obtained from superficial and deeply invasive bladder carcinomas were studied. Of the 56 bladder tumors 42 (75%) expressed EGFR, 34 (60.71%) MUC-1 and 15 (26.78%) MUC-2; while 7 tumors (12.5%) coexpressed MUC-1 and MUC-2 proteins. Immunohistochemical scores showed higher levels of EGFR than of MUC-1 (P <0.05) and MUC-2 (P = 0.000) and higher levels of MUC-1 than MUC-2 (P = 0.0010). EGFR and MUC-1 expression was stronger in high-grade tumors (grade 2/3) than in low-grade (grade 1/2) ones (P <0.05) and stronger in muscle invasive tumors (T2-T4) than in superficial (Ta-T1) ones. Linear regression showed a significant (P <0.05) correlation between EGFR and MUC-1 proteins, but no correlation between EGFR and MUC-2 or between MUC-1 and MUC-2. Immunohistochemical expression of EGFR, MUC-1 and MUC-2 increases as primary bladder carcinomas acquire a more aggressive phenotype. Differences in the distribution of EGFR and mucins within the urothelium may be of diagnostic and prognostic value. These antigens may be useful as markers for bladder malignancy.


Assuntos
Carcinoma in Situ/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células de Transição/metabolismo , Receptores ErbB/metabolismo , Mucina-1/metabolismo , Mucinas/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Idoso , Carcinoma in Situ/mortalidade , Carcinoma in Situ/patologia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/patologia , Seguimentos , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Mucina-2 , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Análise de Regressão , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia
11.
Acta Oncol ; 38(5): 655-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10427957

RESUMO

The clinicopathological features of a rare case of primary non-Hodgkin's hepatic lymphoma (PHL) are described and compared to those of the other 76 cases reported in the world literature. PHL is mainly a disease of Caucasian, middle-aged males and, in approximately half of the reported cases, was associated with other diseases involving depression or chronic stimulation of the immune system. Right upper abdominal and epigastric pain with loss of weight are the most common presenting symptoms. The tumour is usually a single large mass involving both hepatic lobes and is almost invariably composed of lymphocytes reacting with B-cell markers. Most tumours are of intermediate or high grade according to the classification of the Working Formulation for Clinical Usage. No correlation is apparent between gross appearance of PHL (massive or nodular) and grade of severity. Chemotherapy or radiotherapy alone appears to be ineffective, while relatively good results can be obtained with combination modalities.


Assuntos
Neoplasias Hepáticas/patologia , Linfoma não Hodgkin/patologia , Adulto , Linfócitos B/imunologia , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/terapia , Linfoma não Hodgkin/diagnóstico , Linfoma não Hodgkin/terapia , Masculino , Estadiamento de Neoplasias , Dor/etiologia , Prognóstico , Redução de Peso
13.
Pathologica ; 89(5): 523-6, 1997 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-9489399

RESUMO

Conjoined twinning is the result of an abnormal developmental process of "twinning" in which two similar weighted and sized twins are partially conjoined and show a total symmetry independently from the pattern of conjunction. They are classified in three groups: Terata Catydidymus, Terata Anadidyma and Terata Anacatadidyma. Among Terata Catydidymus the dicephalus subtype is a rare abnormality with a severe prognosis compared to other subtypes as: diprosopus, pyophagus and ischiopagus. We report the case of a fetus at the 15th weeks of pregnancy. The external examination revealed severe diffuse somatic malformations consisting of dicephalia with a double neck in conjunction to a single chest, a single abdomen, a double spine conjoined distally near the sacrum, buds of ribs in between the two spines with mid clavicular and scapular fusion following the major axis of the two bones. Arms and legs revealed no abnormalities. Central nervous system structures were normally developed and the two hemispheres seemed completely separated and independent one to the other. We believe that the case described is interesting being Terata Catydidymus a rare phenomenon, being the dicephalus subtype still lesser frequent and its occurrence in males quite exceptional.


Assuntos
Anormalidades Múltiplas/patologia , Feto/anormalidades , Cabeça/anormalidades , Gêmeos Unidos/patologia , Anormalidades Múltiplas/embriologia , Feto/patologia , Idade Gestacional , Cabeça/embriologia , Cabeça/patologia , Humanos , Masculino , Prognóstico , Gêmeos Unidos/embriologia
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