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1.
Autophagy ; 19(10): 2733-2751, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37418591

RESUMO

Apoptosis is a tightly controlled cell death program executed by proteases, the so-called caspases. It plays an important role in tissue homeostasis and is often dysregulated in cancer. Here, we identified FYCO1, a protein that promotes microtubule plus end-directed transport of autophagic and endosomal vesicles as a molecular interaction partner of activated CASP8 (caspase 8). The absence of FYCO1 sensitized cells to basal and TNFSF10/TRAIL-induced apoptosis by receptor accumulation and stabilization of the Death Inducing Signaling Complex (DISC). Loss of FYCO1 resulted in impaired transport of TNFRSF10B/TRAIL-R2/DR5 (TNF receptor superfamily member 10b) to the lysosomes in TNFSF10/TRAIL-stimulated cells. More in detail, we show that FYCO1 interacted via its C-terminal GOLD domain with the CCZ1-MON1A complex, which is necessary for RAB7A activation and for the fusion of autophagosomal/endosomal vesicles with lysosomes. We demonstrated that FYCO1 is a novel and specific CASP8 substrate. The cleavage at aspartate 1306 resulted in the release of the C-terminal GOLD domain, inactivating FYCO1 function, and allowing for the progression of apoptosis. Furthermore, the lack of FYCO1 resulted in a stronger and prolonged formation of the TNFRSF1A/TNF-R1 signaling complex. Thus, FYCO1 limits the ligand-induced and steady-state signaling of TNFR-superfamily members, providing a control mechanism that fine-tunes both apoptotic and inflammatory answers.Abbreviations: AP: affinity purification; CHX: cycloheximide; co-IP: co-immunoprecipitation; CRISPR: clustered regularly interspaced short palindromic repeats; DISC: death-inducing signaling complex; DR: death receptors; doxy: doxycycline; GEF: guanine nucleotide exchange factor; ind: inducible; KD: knockdown; KO: knockout; MS: mass spectrometry; shRNA: short hairpin RNA; siRNA: small interfering RNA; TIP: two-step co-immunoprecipitation; WB: western blot.


Assuntos
Autofagia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF , Caspase 8/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Apoptose , Caspases/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Caspase 9/metabolismo
2.
Curr Protoc Mol Biol ; 125(1): e80, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30375742

RESUMO

In the past few decades, numerous approaches have been developed to investigate protein-protein and protein-nucleic acid interactions (PPIs and PNIs). Affinity purification methods such as co-immunoprecipitation (co-IP) are commonly used to detect and isolate the macromolecular complexesresulting from these interactions. In this article, we describe a two-step co-immunoprecipitation (TIP) technique. As compared to standard co-IP, TIP provides increased specificity in the isolation of PPIs or PNIs under native expression conditions, dramatically reducing the abundance of nonspecific binders and thus facilitating downstream analyses of the interaction complexes. Here, we report a detailed TIP procedure that we used to purify a protein-protein complex from Burkitt lymphoma cells and from primary human CD4+ T cells. In addition, this unit describes an application of TIP for the isolation of transcription-factor-bound chromatin. © 2018 by John Wiley & Sons, Inc.


Assuntos
Separação Celular/métodos , Imunoprecipitação/métodos , Linhagem Celular , Células/química , Células/metabolismo , Humanos , Mapeamento de Interação de Proteínas
3.
Radiol Case Rep ; 12(3): 483-487, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28828107

RESUMO

Bilateral adrenal hemorrhage is a rare condition, which is burdened by potentially life-threatening consequences related to the development of acute adrenal insufficiency. Despite treatment with stress-dose glucocorticoids, a mortality rate of 15% has been reported, which varies according to the severity of underlying predisposing illness and could be much more higher if the adrenal insufficiency is not promptly recognized. An early diagnosis is crucial, though, because of nonspecific clinical and laboratory findings, adrenal hemorrhage is rarely suspected. Therefore, imaging has a pivotal role for the diagnosis of this uncommon condition but, despite adrenal hematomas characteristically appear round or oval with peripheral fat stranding, their initial presentation could be ambiguous. The authors describe a case of postoperative bilateral adrenal hemorrhage initially presenting at computed tomography scan as thickening of both glands surrounded by fat stranding, which led to close monitoring of adrenal function before unequivocal hemorrhage developed.

4.
Pituitary ; 20(2): 201-209, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27730456

RESUMO

PURPOSE: Our hypothesis was that pituitary macroadenomas show different areas of consistency detectable by enhanced magnetic resonance imaging (MRI) with Dynamic study during gadolinium administration. MATERIALS AND METHODS: We analysed 21 patients with pituitary macroadenomas between June 2013 and June 2015. All patients underwent trans-sphenoidal surgery and neurosurgeon described macroadenomas consistency. Similarly, two neuroradiologists manually drew regions of interest (ROIs) inside the solid-appearing portions of macroadenoma and in the normal white matter both on dynamic and post-contrast acquisitions. The ratio between these ROIs, defined as Signal Intensity Ratio (SIR), allowed obtaining signal intensity curves over time on dynamic acquisition and a single value on post-contrast MRI. SIR values best differentiating solid from soft macroadenoma components were calculated and correlated with pathologic patterns. A two-sample T test and empiric receiver operating characteristic (ROC) curve of SIR was performed. RESULTS: According to ROC analysis, the SIR value of 1.92, obtained by dynamic acquisition, best distinguished soft and hard components. All the specimens from soft components were characterized by high cellularity, high representation of vascularization and micro-haemorrhage and low percentage of collagen content. The reverse was evident in hard components. CONCLUSIONS: We demonstrated that dynamic MRI acquisition could distinguish with good accuracy macroadenomas consistency.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias Hipofisárias/diagnóstico , Adulto , Idoso , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/cirurgia , Curva ROC
6.
J Neuroimaging ; 26(1): 95-102, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25996840

RESUMO

BACKGROUND AND PURPOSE: The aim of this study was to investigate the characteristic pattern of age-related cortical thinning in patients with Down Syndrome (DS), as assessed by MRI and automatic cortical thickness measurements. METHODS: Ninety-one non-demented subjects with DS (range 11-53 years) were examined using a 1.5 T scanner. MRI-based quantification of cortical thickness was performed using FreeSurfer software package., The Pearson product-moment correlation coefficient between age and mean cortical thickness was evaluated for all subjects participating in the study. RESULTS: A significant negative correlation between cortical thickness and age was found bilaterally in the frontal, temporal, parietal and cingulate gyrus. Specific investigation of cerebral lobes showed a more evident involvement of the frontal one, compared to others. Moreover, the age related reduction of cortical thickness appeared to be more significant and rapid in patients between 20 and 30 years of age. CONCLUSIONS: Our findings showed that Down Syndrome subjects are affected by a diffuse cortical thinning. The involvement of cortical structures can be observed at an earlier age than previous studies have reported.


Assuntos
Atrofia/patologia , Córtex Cerebral/patologia , Síndrome de Down/patologia , Adolescente , Adulto , Envelhecimento , Atrofia/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Criança , Síndrome de Down/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tamanho do Órgão/fisiologia , Adulto Jovem
7.
Neuroradiol J ; 27(4): 397-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25196610

RESUMO

The identification of diffuse axonal injury (DAI) can be difficult, especially using conventional imaging (CT or MRI), which usually appears normal. Diffusion tensor imaging (DTI) is useful in identifying white matter abnormalities in patients with DAI. We describe the case of a 17-year-old female with severe closed head injury and right-side hemiparesis, studied with DTI and MR-tractography. In this case, DTI was useful to detect focal and diffuse signs of DAI.


Assuntos
Pedúnculo Cerebral/diagnóstico por imagem , Lesão Axonal Difusa/diagnóstico por imagem , Traumatismos Cranianos Fechados/diagnóstico por imagem , Paresia/diagnóstico por imagem , Tratos Piramidais/diagnóstico por imagem , Adolescente , Lesão Axonal Difusa/complicações , Imagem de Tensor de Difusão , Feminino , Traumatismos Cranianos Fechados/complicações , Humanos , Imageamento por Ressonância Magnética , Paresia/etiologia
9.
Crit Rev Oncog ; 18(4): 303-15, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23614617

RESUMO

Prostate cancer is one of the most common causes of cancer-related death. The management of prostate cancer patients has become increasingly complex, consequently calling on the need for identifying and validating prognostic and predictive biomarkers. Growing evidence indicates that microRNAs play a crucial role in the pathobiology of neoplastic diseases. The deregulation of the cellular "miRNome" in prostate cancer has been connected with multiple tumor-promoting activities such as aberrant activation of growth signals, anti-apoptotic effects, prometastatic mechanisms, alteration of the androgen receptor pathway, and regulation of the cancer stem cell phenotype. With the elucidation of molecular mechanisms controlled by microRNAs, investigations have been conducted in an attempt to exploit these molecules in the clinical setting. Moreover, the multifaceted biological activity of microRNAs makes them an attractive candidate as anticancer agents. This review summarizes the current knowledge on microRNA deregulation in prostate cancer, and the rationale underlying their exploitation as cancer biomarkers and therapeutics.


Assuntos
Biomarcadores Tumorais/genética , MicroRNAs/fisiologia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Animais , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Neoplasias da Próstata/genética
10.
Cancer J ; 18(3): 253-61, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22647362

RESUMO

The management of prostate cancer patients is rapidly changing. The extended survival seen in randomized phase III trials with new molecules has significantly enriched the therapeutic armamentarium, and ongoing clinical trials are assessing whether the integration of these active drugs within established therapeutic regimens results in a further benefit for patients. This complex scenario is raising the need for the identification and validation of biomarkers able to drive the decision-making process during the course of the disease. Compelling evidence has documented the role of microRNAs in cancer biology, and their multifaceted biological activity makes them an attractive candidate as diagnostic, prognostic, and predictive biomarkers. This review summarizes the current knowledge about microRNA deregulation in prostate cancer, how these molecules have been investigated in the clinical setting, and strategies investigators should consider for sharpening their potential.


Assuntos
Biomarcadores Tumorais , MicroRNAs/genética , Metástase Neoplásica/genética , Neoplasias da Próstata/genética , Apoptose/genética , Pontos de Checagem do Ciclo Celular/genética , Proliferação de Células , Perfilação da Expressão Gênica , Humanos , Masculino , MicroRNAs/metabolismo , Invasividade Neoplásica/genética , Prognóstico , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia
11.
Neurosurgery ; 69(3): 696-704; discussion 704-5, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21471830

RESUMO

BACKGROUND: Magnetic resonance with diffusion tensor image (DTI) may be able to estimate trajectories compatible with subcortical tracts close to brain lesions. A limit of DTI is brain shifting (movement of the brain after dural opening and tumor resection). OBJECTIVE: To calculate the brain shift of trajectories compatible with the corticospinal tract (CST) in patients undergoing glioma resection and predict the shift directions of CST. METHODS: DTI was acquired in 20 patients and carried out through 12 noncollinear directions. Dedicated software "merged" all sequences acquired with tractographic processing and the whole dataset was sent to the neuronavigation system. Preoperative, after dural opening (in 11) and tumor resection (in all) DTI acquisitions were performed to evaluate CST shifting. The extent of shifting was considered as the maximum distance between the preoperative and intraoperative contours of the trajectories. RESULTS: An outward shift of CST was observed in 8 patients and an inward shift in 10 patients during surgery. In the remaining 2 patients, no intraoperative displacement was detected. Only peritumoral edema showed a statistically significant correlation with the amount of shift. In those patients in which DTI was acquired after dural opening as well (11 patients), an outward shifting of CST was evident in that phase. CONCLUSION: The use of intraoperative DTI demonstrated brain shifting of the CST. DTI evaluation of white matter tracts can be used during surgical procedures only if updated with intraoperative acquisitions.


Assuntos
Imagem de Tensor de Difusão/métodos , Monitorização Intraoperatória/métodos , Procedimentos Neurocirúrgicos/métodos , Tratos Piramidais/patologia , Tratos Piramidais/cirurgia , Adulto , Idoso , Edema Encefálico/cirurgia , Neoplasias Encefálicas/cirurgia , Craniotomia , Feminino , Glioma/cirurgia , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Curva ROC
12.
Eur Radiol ; 20(10): 2475-81, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20455066

RESUMO

OBJECTIVE: To demonstrate the accuracy of magnetic resonance tractograpghy (MRT) in localizing the cortical spinal tract (CST) close to brain tumours by using intraoperative electric subcortical stimulation. METHODS: Nine patients with intra-axial brain tumours underwent neurosurgery. Planning was based on analysis of the course of streamlines compatible with the CST. After tumour removal, intraoperative MRT was reacquired. Sites at various distance from the CST were repeatedly stimulated to assess whether registered motor evoked potential (MEP) could be elicited. All patients were assessed clinically both pre- and postoperatively. RESULTS: The motor function was preserved in all patients. In all patients intraoperative MRT demonstrated shift of the bundle position caused by the surgical procedure. The distance between the estimated intraoperative CST and the point of elicited MEP was 1 cm or less in all nine patients. At distances greater than 2 cm, no patient reported positive MEP. CONCLUSION: Intraoperative MRT is a reliable technique for localization of CST. In all patients MEP were elicited by direct subcortical electrical stimulation at a distance below 1 cm from the CST as represented by MRT. Brain shifting might impact this evaluation since CST position may change during surgery in the range of 8 mm.


Assuntos
Mapeamento Encefálico/métodos , Imagem de Tensor de Difusão/métodos , Tratos Piramidais/patologia , Idoso , Encéfalo/patologia , Encéfalo/cirurgia , Neoplasias Encefálicas/patologia , Estimulação Elétrica , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuronavegação/métodos , Procedimentos Neurocirúrgicos/métodos , Reprodutibilidade dos Testes
13.
Methods Mol Biol ; 614: 149-60, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20225042

RESUMO

The manipulation of cell differentiation is important to create new sources for the treatment of degenerative diseases or solve cell depletion after aggressive therapy against cancer. In this chapter, the use of a tissue-specific promoter lentiviral vector to obtain a myocardial pure lineage from murine embryonic stem cells (mES) is described in detail. Since the cardiac isoform of troponin I gene product is not expressed in skeletal or other muscle types, short mouse cardiac troponin proximal promoter is used to drive reporter genes. Cells are infected simultaneously with two lentiviral vectors, the first expressing EGFP to monitor the transduction efficiency, and the other expressing a puromycin resistance gene to select the specific cells of interest. This technical approach describes a method to obtain a pure cardiomyocyte population and can be applied to other lineages of interest.


Assuntos
Diferenciação Celular , Vetores Genéticos , Lentivirus/genética , Animais , Células-Tronco Embrionárias/citologia , Camundongos , Regiões Promotoras Genéticas
14.
Endocr Relat Cancer ; 17(1): F1-17, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19779034

RESUMO

Despite much progress in prostate cancer management, new diagnostic, prognostic and therapeutic tools are needed to predict disease severity, choose among the available treatments and establish more effective therapies for advanced prostate cancer. In the last few years, compelling evidence has documented the role of microRNAs as new broad-spectrum oncogenes or tumour suppressor genes, thus their use as diagnostic, prognostic and therapeutic biomolecules is envisaged. This review extensively and critically summarizes the current knowledge about microRNA deregulation in prostate cancer disease, underlining present limits and future perspectives.


Assuntos
Adenocarcinoma/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias da Próstata/genética , RNA Neoplásico/genética , Adenocarcinoma/diagnóstico , Adenocarcinoma/terapia , Androgênios , Transformação Celular Neoplásica/genética , Progressão da Doença , Perfilação da Expressão Gênica , Genes Supressores de Tumor , Humanos , Masculino , MicroRNAs/análise , Invasividade Neoplásica/genética , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Neoplasias Hormônio-Dependentes/diagnóstico , Neoplasias Hormônio-Dependentes/genética , Neoplasias Hormônio-Dependentes/terapia , Prognóstico , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Proteínas Proto-Oncogênicas c-myc/fisiologia
15.
PLoS One ; 3(12): e4029, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19107213

RESUMO

BACKGROUND: MiR-221 and miR-222 are two highly homologous microRNAs whose upregulation has been recently described in several types of human tumors, for some of which their oncogenic role was explained by the discovery of their target p27, a key cell cycle regulator. We previously showed this regulatory relationship in prostate carcinoma cell lines in vitro, underlying the role of miR-221/222 as inducers of proliferation and tumorigenicity. METHODOLOGY/PRINCIPAL FINDINGS: Here we describe a number of in vivo approaches confirming our previous data. The ectopic overexpression of miR-221 is able, per se, to confer a high growth advantage to LNCaP-derived tumors in SCID mice. Consistently, the anti-miR-221/222 antagomir treatment of established subcutaneous tumors derived from the highly aggressive PC3 cell line, naturally expressing high levels of miR-221/222, reduces tumor growth by increasing intratumoral p27 amount; this effect is long lasting, as it is detectable as long as 25 days after the treatment. Furthermore, we provide evidence in favour of a clinical relevance of the role of miR-221/222 in prostate carcinoma, by showing their general upregulation in patient-derived primary cell lines, where we find a significant inverse correlation with p27 expression. CONCLUSIONS/SIGNIFICANCE: These findings suggest that modulating miR-221/222 levels may have a therapeutic potential in prostate carcinoma.


Assuntos
Carcinoma/patologia , Proliferação de Células/efeitos dos fármacos , MicroRNAs/antagonistas & inibidores , Oligonucleotídeos/farmacologia , Neoplasias da Próstata/patologia , Idoso , Animais , Sequência de Bases , Carcinoma/genética , Progressão da Doença , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Regulação para Baixo/fisiologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Terapia Genética , Humanos , Masculino , Camundongos , Camundongos SCID , MicroRNAs/genética , Pessoa de Meia-Idade , Antígeno Nuclear de Célula em Proliferação/genética , Neoplasias da Próstata/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Nat Med ; 14(11): 1271-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18931683

RESUMO

MicroRNAs (miRNAs) are noncoding small RNAs that repress protein translation by targeting specific messenger RNAs. miR-15a and miR-16-1 act as putative tumor suppressors by targeting the oncogene BCL2. These miRNAs form a cluster at the chromosomal region 13q14, which is frequently deleted in cancer. Here, we report that the miR-15a and miR-16-1 cluster targets CCND1 (encoding cyclin D1) and WNT3A, which promotes several tumorigenic features such as survival, proliferation and invasion. In cancer cells of advanced prostate tumors, the miR-15a and miR-16 level is significantly decreased, whereas the expression of BCL2, CCND1 and WNT3A is inversely upregulated. Delivery of antagomirs specific for miR-15a and miR-16 to normal mouse prostate results in marked hyperplasia, and knockdown of miR-15a and miR-16 promotes survival, proliferation and invasiveness of untransformed prostate cells, which become tumorigenic in immunodeficient NOD-SCID mice. Conversely, reconstitution of miR-15a and miR-16-1 expression results in growth arrest, apoptosis and marked regression of prostate tumor xenografts. Altogether, we propose that miR-15a and miR-16 act as tumor suppressor genes in prostate cancer through the control of cell survival, proliferation and invasion. These findings have therapeutic implications and may be exploited for future treatment of prostate cancer.


Assuntos
MicroRNAs/genética , Família Multigênica/genética , Proteínas Oncogênicas/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Animais , Linhagem Celular Tumoral , Ciclina D1/genética , Ciclina D1/metabolismo , Humanos , Masculino , Camundongos , Proteínas Oncogênicas/genética , Neoplasias da Próstata/patologia , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Proteína Wnt3 , Proteína Wnt3A
17.
Haematologica ; 93(12): 1899-902, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18838478

RESUMO

Resistance to chemotherapy-induced cell death represents a major obstacle in the treatment of acute myeloid leukemia. APRIL (A Proliferation Inducing Ligand) is a member of the tumor necrosis factor superfamily that plays a key role in normal B-cell development, while promoting survival and proliferation of malignant B cells. We investigated APRIL expression and activity in acute myeloid leukemia. We found that APRIL mRNA and protein, including the secreted form, are expressed in leukemic cells of patients with M0, M2 and M4 acute myeloid leukemia subtypes but not in normal hematopoietic progenitors. Retrovirus-mediated APRIL expression in normal hematopoietic progenitors confers resistance to chemotherapeutic drugs-induced apoptosis. Conversely, blocking APRIL function by recombinant soluble APRIL receptors increased chemotherapeutic drugs-induced cell adeath in acute myeloid leukemia cells. These results indicate that APRIL acts in an autocrine fashion to protect acute myeloid leukemia cells from drug-induced death and foresee a therapeutic potential of APRIL antagonists in the treatment of acute myeloid leukemia.


Assuntos
Antineoplásicos/farmacocinética , Resistencia a Medicamentos Antineoplásicos , Leucemia Mieloide Aguda/patologia , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/antagonistas & inibidores , Comunicação Autócrina , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Células Tumorais Cultivadas
18.
Cancer Invest ; 25(4): 256-66, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17612936

RESUMO

In the last years, an increasing number of experiments has provided compelling evidence for a casual role of Ras protein mutations, resulting in their constitutive activation, in thyroid carcinogenesis. However, despite the clear involvement of Ras proteins in thyroid carcinogenesis, the nature of most of the target genes, whose expression is modulated by the Ras-induced signaling pathways and that are ultimately responsible for Ras-induced cellular transformation, remains largely unknown. To analyze Ras-dependent modulation of gene expression in thyroid cells we took advantage of a differentiated rat thyroid cell line, FRTL-5. As a model for Ras-dependent thyroid transformation, we used FRTL-5 cells infected with the Kirsten murine sarcoma virus, carrying the v-Ki-Ras oncogene. The infected cells (FRTL-5 v-Ki-Ras) have lost expression of the thyroid differentiation markers and also are completely transformed. We hybridized two different Affimetrix chips containing probe sets interrogating both known rat genes and ESTs for a total of more than 17,000 sequences using mRNA extracted from FRTL-5 and FRTL-5 v-Ki-Ras cell lines. We identified about 50 genes whose expression was induced and about 40 genes whose expression was downregulated more than 10-fold by Ras. We confirmed the differential expression of many of these genes in FRTL-5 v-Ki-Ras as compared to parental cells by using alternative techniques. Remarkably, we investigated the expression of some of the Ras-regulated genes in human thyroid carcinoma cell lines and tumor samples, our results, therefore, providing a new molecular profile of the genes involved in thyroid neoplastic transformation.


Assuntos
Transformação Celular Neoplásica , Perfilação da Expressão Gênica , Genes ras , Neoplasias da Glândula Tireoide/genética , Animais , Antígeno CD24/análise , Linhagem Celular Tumoral , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Ratos
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