Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
2.
Clin Gastroenterol Hepatol ; 21(2): 406-414.e7, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35124272

RESUMO

BACKGROUND & AIMS: There is conflicting evidence regarding the prevalence of and risk factors for metabolic-associated fatty liver disease (MAFLD) in patients with inflammatory bowel disease (IBD). We aimed to determine MAFLD prevalence and risk factors in IBD patients. METHODS: Cross-sectional, case-control study included all consecutive IBD patients treated at 2 different university hospitals. Controls were subjects randomly selected from the general population and matched by age, sex, type 2 diabetes status, and body mass index in a 1:2 ratio. MAFLD was confirmed by controlled attenuation parameter. Liver biopsies were collected when MAFLD with significant liver fibrosis was suspected. In addition, age- and fibrosis stage-paired non-IBD patients with biopsy-proven MAFLD served as a secondary control group. RESULTS: Eight hundred thirty-one IBD patients and 1718 controls were included. The prevalence of MAFLD and advanced liver fibrosis (transient elastography ≥9.7 kPa) was 42.00% and 9.50%, respectively, in IBD patients and 32.77% and 2.31%, respectively, in the general population (P < .001). A diagnosis of IBD was an independent predictor of MAFLD (adjusted odds ratio, 1.99; P < .001) and an independent risk factor for advanced liver fibrosis (adjusted odds ratio, 5.55; P < .001). Liver biopsies were obtained from 40 IBD patients; MAFLD was confirmed in all cases, and fibrosis of any degree was confirmed in 25 of 40 cases (62.5%). Body mass index and type 2 diabetes prevalence were significantly lower in IBD-MAFLD patients than in severity-paired patients with biopsy-proven MAFLD. CONCLUSIONS: MAFLD and liver fibrosis are particularly prevalent in IBD patients, regardless of the influence of classic metabolic risk factors.


Assuntos
Diabetes Mellitus Tipo 2 , Doenças Inflamatórias Intestinais , Hepatopatia Gordurosa não Alcoólica , Humanos , Estudos de Casos e Controles , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Doenças Inflamatórias Intestinais/complicações , Cirrose Hepática/complicações , Cirrose Hepática/epidemiologia , Fatores de Risco , Masculino , Feminino
3.
Lancet Haematol ; 9(6): e425-e433, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35654076

RESUMO

BACKGROUND: The calcineurin pathway is often activated in mycosis fungoides. We aimed to assess the activity and safety of topical pimecrolimus, a calcineurin inhibitor, in patients with early mycosis fungoides. METHODS: PimTo-MF was a single-arm, multicentre, phase 2 trial done at six medical centres in Spain. Patients (aged ≥18 years) had histologically confirmed early mycosis fungoides (stages IA-IIA) and an Eastern Cooperative Oncology Group performance status of 0-1. Key exclusion criteria included the use of concurrent treatments for mycosis fungoides, including sunbathing, topical or systemic corticosteroids, and other calcineurin inhibitors. Patients applied topical pimecrolimus 1% cream on their skin lesions twice daily for 16 weeks (1 g per 2% of body surface), with subsequent follow-up of 12 months. Dosage modifications were not allowed. To evaluate adherence to the treatment, patients were instructed to return all empty tubes to the hospital (as per drug accountability protocols). The primary endpoint was the overall response ratein the intention-to-treat population. PimTo-MF is registered with EudraCT, 2014-001377-14, and is complete. FINDINGS: Between March 1, 2015, and Sept 30, 2016, 39 patients were enrolled. All patients were assessable, with a median age of 51·5 years (IQR 45-62), and the population was predominantly male (24 male [62%], 15 female [38%]). Median follow-up after baseline was 5·7 years (IQR 5·7-6·2). 22 (56%) of 39 patients had an overall response (one complete response, 21 partial responses). Responses were observed across IA (14 [54%] of 26 patients) and IB (eight [73%] of 11 patients) clinical stages, but not IIA. Topical pimecrolimus was well tolerated and no patient required a dose reduction or discontinued treatment because of unacceptable drug-related toxicity. No patients were lost to follow-up or discontinued treatment. 13 (33%) of 39 patients reported adverse events; transitory mild burning or pruritus (grade 1) was the most common, seen in eight (21%) patients. In three (8%) of these patients, the burning or pruritus was considered related to treatment. No grade 4 or 5 adverse events were observed. INTERPRETATION: Pimecrolimus 1% cream seems active and safe in patients with early stage mycosis fungoides. Our findings should be taken with caution until long-term follow-up data are obtained that confirm the safety of this treatment. Further controlled clinical trials are warranted to confirm these results. FUNDING: Instituto de Salud Carlos III and the European Regional Development Fund. TRANSLATION: For the Spanish translation of the abstract see Supplementary Materials section.


Assuntos
Micose Fungoide , Neoplasias Cutâneas , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Micose Fungoide/tratamento farmacológico , Prurido/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Tacrolimo/efeitos adversos , Tacrolimo/análogos & derivados
4.
J Invest Dermatol ; 142(5): 1391-1400.e15, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34687742

RESUMO

Developing mechanistic rationales can improve the clinical management of cutaneous T-cell lymphomas. There is considerable genetic and biological evidence of a malignant network of signaling mechanisms, highly influenced by deregulated TCR/PLCγ1 activity, controlling the biology of these lesions. In addition, activated signal transducer and activator of transcription 3 is associated with clinical progression, although the alterations responsible for this have not been fully elucidated. Here, we studied PLCγ1-dependent mechanisms that can mediate STAT3 activation and control tumor growth and progression. Downstream of PLCγ1, the pharmacological inhibition and genetic knockdown of protein kinase C theta (PKCθ) inhibited signal transducer and activator of transcription 3 activation, impaired proliferation, and promoted apoptosis in cutaneous T-cell lymphoma cells. A PKCθ-dependent transcriptome in mycosis fungoides/Sézary syndrome cells revealed potential effector genes controlling cytokine signaling, TP53, and actin cytoskeleton dynamics. Consistently, an in vivo chicken embryo model xenografted with mycosis fungoides cells showed that PKCθ blockage abrogates tumor growth and spread to distant organs. Finally, the expression of a number of PKCθ target genes found in mycosis fungoides cells significantly correlated with that of PRKCQ (PKCθ) in 81 human mycosis fungoides samples. In summary, PKCθ can play a central role in the activation of malignant cutaneous T-cell lymphoma mechanisms via multiple routes, including, but not restricted to, STAT3. These mechanisms may, in turn, serve as targets for specific therapies.


Assuntos
Linfoma Cutâneo de Células T , Micose Fungoide , Neoplasias Cutâneas , Animais , Embrião de Galinha , Linfoma Cutâneo de Células T/genética , Micose Fungoide/genética , Proteína Quinase C-theta/genética , Proteína Quinase C-theta/metabolismo , Fator de Transcrição STAT3/metabolismo , Neoplasias Cutâneas/genética
5.
Viruses ; 13(4)2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33917265

RESUMO

Chronic hepatitis C infection (HCV) activates a systemic cell-mediated immune response characterized by the production of IFNγ and an innate immune response addressed by the activation of TLR signaling. We aimed to investigate whether HCV eradication by direct acting antivirals (DAA) leads to a recovery in cell-mediated immune response and TLR expression and functionality. Blood samples were obtained in HCV infected patients before DAA treatment and at week +48 after the end of treatment. Results were compared to healthy controls. Cell surface expression of TLR8 was assessed on peripheral blood mononuclear cells (PBMCs) by flow cytometry. Freshly isolated PBMCs were cultured with specific TLR8 agonists and intracellular production of cytokines was determined by flow-cytometry after ex vivo TLR8 activation with ssRNA 40. Production of IFNγ, IL2 and IL17 was assessed by flow cytometry in T cells after polyclonal activation. Included were 50 HCV-infected patients and 15 controls. TLR8 expression in PBMCs was significantly increased before treatment and recovered normal levels at week +48. Production of IL1b, IL6 and TNFα dependent on the activation of TLR8 in PBMCs was also increased in patients before DAA treatment, with a significant reduction at week +48. Combined expression of IFNγ and IL2 in CD4+ T cells in HCV-infected patients was significantly increased compared to controls and recovered normal levels at week +48. DAA-mediated clearance of HCV is associated with a decreased expression and activation of TLR8 in PBMCs until healthy control levels which is accompanied by a reduction in the Th1 response.


Assuntos
Antivirais/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/imunologia , Interferon gama/análise , Interleucina-2/análise , Receptor 8 Toll-Like/genética , Adulto , Feminino , Citometria de Fluxo , Expressão Gênica , Humanos , Imunidade Inata , Interferon gama/imunologia , Interleucina-2/imunologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/fisiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Células Th1/imunologia , Receptor 8 Toll-Like/imunologia
6.
Cancers (Basel) ; 13(8)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923722

RESUMO

Primary cutaneous T-cell lymphomas (CTCLs) constitute a heterogeneous group of diseases that affect the skin. Mycosis fungoides (MF) and Sézary syndrome (SS) account for the majority of these lesions and have recently been the focus of extensive translational research. This review describes and discusses the main pathobiological manifestations of MF/SS, the molecular and clinical features currently used for diagnosis and staging, and the different therapies already approved or under development. Furthermore, we highlight and discuss the main findings illuminating key molecular mechanisms that can act as drivers for the development and progression of MF/SS. These seem to make up an orchestrated constellation of genomic and environmental alterations generated around deregulated T-cell receptor (TCR)/phospholipase C, gamma 1, (PLCG1) and Janus kinase/ signal transducer and activator of transcription (JAK/STAT) activities that do indeed provide us with novel opportunities for diagnosis and therapy.

7.
PLoS One ; 15(7): e0232517, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32687503

RESUMO

AIMS: Merkel cell carcinoma (MCC) is an aggressive primary neuroendocrine tumor of the skin, associated with Merkel cell polyomavirus (MCPyV) in 49-89% of cases, depending on the country of origin and the techniques of detection. The presence of MCPyV defines heterogeneity in MCC; MCPyV-negative cases bear a much higher mutational load, with a distinct ultraviolet signature pattern featuring C > T transitions, as a consequence of exposure to ultraviolet light radiation. MCC stroma has not been thoroughly studied, although MCC patients benefit from therapy targeting PD1/PDL1. METHODS AND RESULTS: In this study, using Tissue Microarrays and immunohistochemistry, we have analyzed a series of 219 MCC cases in relation to the presence of MCPyV, and confirmed that the presence of MCPyV is associated with changes not only in the neoplastic cells, but also in the composition of the tumor stroma. Thus, MCPyV, found in 101/176 (57,4%) analyzable cases, exhibits changes in its tumor morphology, the density of the inflammatory infiltrate, the phenotype of the neoplastic cells, and the cell composition of the tumor stroma. MCPyV presence is negatively correlated with a higher level of p53 expression, and associated with a very high frequency (86%) of HLA-I expression loss, a higher apoptotic index, and a stroma richer in T-cells, cytotoxic T-cells, macrophages, PDL1-positive macrophages, and B-cells. CONCLUSIONS: Our findings provide evidence of the basic heterogeneity of MCC, supporting the hypothesis that the presence of MCPyV may induce a rich inflammatory response, which is at least partially avoided through loss of HLA-I antigen expression. On the other hand, MCPyV-negative cases show a much higher frequency of stronger p53 expression and, probably, p53 alterations.


Assuntos
Carcinoma de Célula de Merkel/patologia , Carcinoma de Célula de Merkel/virologia , Poliomavírus das Células de Merkel/fisiologia , Fenótipo , Microambiente Tumoral , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Sci Rep ; 10(1): 6721, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32317694

RESUMO

Patients diagnosed with T-cell leukemias and T-cell lymphomas (TCLs) still have a poor prognosis and an inadequate response to current therapies, highlighting the need for targeted treatments. We have analyzed the potential therapeutic value of the farnesyltransferase inhibitor, tipifarnib, in 25 TCL cell lines through the identification of genomic and/or immunohistochemical markers of tipifarnib sensitivity. More than half of the cell lines (60%) were considered to be sensitive. Tipifarnib reduced cell viability in these T-cell leukemia and TCL cell lines, induced apoptosis and modified the cell cycle. A mutational study showed TP53, NOTCH1 and DNMT3 to be mutated in 84.6%, 69.2% and 30.0% of sensitive cell lines, and in 62.5%, 0% and 0% of resistant cell lines, respectively. An immunohistochemistry study showed that p-ERK and RelB were associated as potential biomarkers of tipifarnib sensitivity and resistance, respectively. Data from RNA-seq show that tipifarnib at IC50 after 72 h downregulated a great variety of pathways, including those controlling cell cycle, metabolism, and ribosomal and mitochondrial activity. This study establishes tipifarnib as a potential therapeutic option in T-cell leukemia and TCL. The mutational state of NOTCH1, p-ERK and RelB could serve as potential biomarkers of tipifarnib sensitivity and resistance.


Assuntos
Biomarcadores Tumorais/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Quinolonas/uso terapêutico , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Linfoma de Células T/tratamento farmacológico , Linfoma de Células T/genética , Linfoma de Células T/patologia , Mutação/genética , Fenótipo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Quinolonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
9.
Transl Psychiatry ; 9(1): 306, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31740729

RESUMO

A better understanding of the molecular mechanisms that participate in the development and clinical manifestations of schizophrenia can lead to improve our ability to diagnose and treat this disease. Previous data strongly associated the levels of deregulated ADAMTS2 expression in peripheral blood mononuclear cells (PBMCs) from patients at first episode of psychosis (up) as well as in clinical responders to treatment with antipsychotic drugs (down). In this current work, we performed an independent validation of such data and studied the mechanisms implicated in the control of ADAMTS2 gene expression. Using a new cohort of drug-naïve schizophrenia patients with clinical follow-up, we confirmed that the expression of ADAMTS2 was highly upregulated in PBMCs at the onset (drug-naïve patients) and downregulated, in clinical responders, after treatment with antipsychotics. Mechanistically, ADAMTS2 expression was activated by dopaminergic signalling (D1-class receptors) and downstream by cAMP/CREB and mitogen-activated protein kinase (MAPK)/ERK signalling. Incubation with antipsychotic drugs and selective PKA and MEK inhibitors abrogated D1-mediated activation of ADAMTS2 in neuronal-like cells. Thus, D1 receptors signalling towards CREB activation might participate in the onset and clinical responses to therapy in schizophrenia patients, by controlling ADAMTS2 expression and activity. The unbiased investigation of molecular mechanisms triggered by antipsychotic drugs may provide a new landscape of novel targets potentially associated with clinical efficacy.


Assuntos
Proteínas ADAMTS/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Dopamina/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Esquizofrenia/fisiopatologia , 8-Bromo Monofosfato de Adenosina Cíclica/análogos & derivados , Proteínas ADAMTS/genética , Animais , Antipsicóticos/farmacologia , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Humanos , Leucócitos Mononucleares/metabolismo , Camundongos , Fosforilação , Esquizofrenia/genética , Esquizofrenia/metabolismo , Transdução de Sinais
10.
Oncotarget ; 9(56): 30869-30882, 2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-30112114

RESUMO

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related deaths worldwide. There is increasing interest in developing specific markers to serve as predictors of response to sorafenib and to guide targeted therapy. Using a sequencing platform designed to study somatic mutations in a selection of 112 genes (HepatoExome), we aimed to characterize lesions from HCC patients and cell lines, and to use the data to study the biological and mechanistic effects of case-specific targeted therapies used alone or in combination with sorafenib. We characterized 331 HCC cases in silico and 32 paired samples obtained prospectively from primary tumors of HCC patients. Each case was analyzed in a time compatible with the requirements of the clinic (within 15 days). In 53% of the discovery cohort cases, we detected unique mutational signatures, with up to 34% of them carrying mutated genes with the potential to guide therapy. In a panel of HCC cell lines, each characterized by a specific mutational signature, sorafenib elicited heterogeneous mechanistic and biological responses, whereas targeted therapy provoked the robust inhibition of cell proliferation and DNA synthesis along with the blockage of AKT/mTOR signaling. The combination of sorafenib with targeted therapies exhibited synergistic anti-HCC biological activity concomitantly with highly effective inhibition of MAPK and AKT/mTOR signaling. Thus, somatic mutations may lead to identify case-specific mechanisms of disease in HCC lesions arising from multiple etiologies. Moreover, targeted therapies guided by molecular characterization, used alone or in combination with sorafenib, can effectively block important HCC disease mechanisms.

11.
PLoS One ; 12(5): e0177524, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28505169

RESUMO

T and NK-cell lymphoma is a collection of aggressive disorders with unfavorable outcome, in which targeted treatments are still at a preliminary phase. To gain deeper insights into the deregulated mechanisms promoting this disease, we searched a panel of 31 representative T-cell and 2 NK-cell lymphoma/leukemia cell lines for predictive markers of response to targeted therapy. To this end, targeted sequencing was performed alongside the expression of specific biomarkers corresponding to potentially activated survival pathways. The study identified TP53, NOTCH1 and DNMT3A as the most frequently mutated genes. We also found common alterations in JAK/STAT and epigenetic pathways. Immunohistochemical analysis showed nuclear accumulation of MYC (in 85% of the cases), NFKB (62%), p-STAT (44%) and p-MAPK (30%). This panel of cell lines captures the complexity of T/NK-cell lymphoproliferative processes samples, with the partial exception of AITL cases. Integrated mutational and immunohistochemical analysis shows that mutational changes cannot fully explain the activation of key survival pathways and the resulting phenotypes. The combined integration of mutational/expression changes forms a useful tool with which new compounds may be assayed.


Assuntos
Linfoma Extranodal de Células T-NK/genética , Linfoma Extranodal de Células T-NK/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Análise por Conglomerados , Perfilação da Expressão Gênica , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imuno-Histoquímica/métodos , Linfoma Extranodal de Células T-NK/tratamento farmacológico , Linfoma Extranodal de Células T-NK/patologia , Terapia de Alvo Molecular , Mutação
13.
J Invest Dermatol ; 137(1): 197-206, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27592799

RESUMO

Merkel cell carcinoma (MCC) is a highly malignant neuroendocrine tumor of the skin whose molecular pathogenesis is not completely understood, despite the role that Merkel cell polyomavirus can play in 55-90% of cases. To study potential mechanisms driving this disease in clinically characterized cases, we searched for somatic mutations using whole-exome sequencing, and extrapolated our findings to study functional biomarkers reporting on the activity of the mutated pathways. Confirming previous results, Merkel cell polyomavirus-negative tumors had higher mutational loads with UV signatures and more frequent mutations in TP53 and RB compared with their Merkel cell polyomavirus-positive counterparts. Despite important genetic differences, the two Merkel cell carcinoma etiologies both exhibited nuclear accumulation of oncogenic transcription factors such as NFAT or nuclear factor of activated T cells (NFAT), P-CREB, and P-STAT3, indicating commonly deregulated pathogenic mechanisms with the potential to serve as targets for therapy. A multivariable analysis identified phosphorylated CRE-binding protein as an independent survival factor with respect to clinical variables and Merkel cell polyomavirus status in our cohort of Merkel cell carcinoma patients.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Célula de Merkel/genética , Carcinoma de Célula de Merkel/virologia , Poliomavírus das Células de Merkel/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/virologia , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Carcinogênese/genética , Carcinoma de Célula de Merkel/mortalidade , Carcinoma de Célula de Merkel/patologia , Estudos de Coortes , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Poliomavírus das Células de Merkel/isolamento & purificação , Análise Multivariada , Mutação , Oncogenes/genética , Prognóstico , Medição de Risco , Transdução de Sinais/genética , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Análise de Sobrevida , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Infecções Tumorais por Vírus/mortalidade , Infecções Tumorais por Vírus/patologia , Raios Ultravioleta/efeitos adversos
15.
Oncotarget ; 6(28): 25452-65, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26327537

RESUMO

Targeted treatment of advanced melanoma could benefit from the precise molecular characterization of melanoma samples. Using a melanoma-specific selection of 217 genes, we performed targeted deep sequencing of a series of biopsies, from advanced melanoma cases, with a Breslow index of ≥ 4 mm, and/or with a loco-regional infiltration in lymph nodes or presenting distant metastasis, as well of a collection of human cell lines. This approach detected 3-4 mutations per case, constituting unique mutational signatures associated with specific inhibitor sensitivity. Functionally, case-specific combinations of inhibitors that simultaneously targeted MAPK-dependent and MAPK-independent mechanisms were most effective at inhibiting melanoma growth, against each specific mutational background. These observations were challenged by characterizing a freshly resected biopsy from a metastatic lesion located in the skin and soft tissue and by testing its associated therapy ex vivo and in vivo using melanocytes and patient-derived xenografted mice, respectively. The results show that upon mutational characterization of advanced melanoma patients, specific mutational profiles can be used for selecting drugs that simultaneously target several deregulated genes/pathways involved in tumor generation or progression.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Análise Mutacional de DNA/métodos , Perfilação da Expressão Gênica/métodos , Melanoma/tratamento farmacológico , Melanoma/genética , Mutação , Medicina de Precisão , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Animais , Biópsia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Predisposição Genética para Doença , Humanos , Metástase Linfática , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Melanócitos/patologia , Melanoma/secundário , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Camundongos Nus , Terapia de Alvo Molecular , Seleção de Pacientes , Fenótipo , Valor Preditivo dos Testes , Inibidores de Proteínas Quinases/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Neoplasias Cutâneas/patologia , Fatores de Tempo , Ensaios Antitumorais Modelo de Xenoenxerto
18.
PLoS One ; 10(3): e0119946, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25775023

RESUMO

We have performed a comparative ultrasequencing study of multiple colorectal lesions obtained simultaneously from four patients. Our data show that benign lesions (adenomatous or hyperplastic polyps) contain a high mutational load. Additionally multiple synchronous colorectal lesions show non overlapping mutational signatures highlighting the degree of heterogeneity between multiple specimens in the same patient. Observations in these cases imply that considering not only the number of mutations but an effective oncogenic combination of mutations can determine the malignant progression of colorectal lesions.


Assuntos
Adenocarcinoma/genética , Adenoma/genética , Evolução Clonal , Neoplasias Colorretais/genética , Mutação , Adenocarcinoma/patologia , Adenoma/patologia , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino
19.
Cancer Cell ; 25(6): 831-45, 2014 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-24882515

RESUMO

Mutually exclusive activating mutations in the GNAQ and GNA11 oncogenes, encoding heterotrimeric Gαq family members, have been identified in ∼ 83% and ∼ 6% of uveal and skin melanomas, respectively. However, the molecular events underlying these GNAQ-driven malignancies are not yet defined, thus limiting the ability to develop cancer-targeted therapies. Here, we focused on the transcriptional coactivator YAP, a critical component of the Hippo signaling pathway that controls organ size. We found that Gαq stimulates YAP through a Trio-Rho/Rac signaling circuitry promoting actin polymerization, independently of phospholipase Cß and the canonical Hippo pathway. Furthermore, we show that Gαq promotes the YAP-dependent growth of uveal melanoma cells, thereby identifying YAP as a suitable therapeutic target in uveal melanoma, a GNAQ/GNA11-initiated human malignancy.


Assuntos
GTP Fosfo-Hidrolases/metabolismo , Subunidades alfa de Proteínas de Ligação ao GTP/genética , Melanoma/genética , Proteínas Nucleares/genética , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Transcrição/genética , Neoplasias Uveais/genética , Animais , Proteínas de Ciclo Celular , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Feminino , GTP Fosfo-Hidrolases/genética , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP , Técnicas de Silenciamento de Genes , Células HEK293 , Xenoenxertos , Via de Sinalização Hippo , Humanos , Melanoma/enzimologia , Melanoma/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Mutação , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais , Neoplasias Cutâneas , Fatores de Transcrição/metabolismo , Transfecção , Neoplasias Uveais/enzimologia , Neoplasias Uveais/metabolismo , Proteínas rho de Ligação ao GTP/genética , Proteínas rho de Ligação ao GTP/metabolismo , Melanoma Maligno Cutâneo
20.
Blood ; 123(13): 2034-43, 2014 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-24497536

RESUMO

Cutaneous T-cell lymphoma (CTCL) is a heterogeneous group of primary cutaneous T-cell lymphoproliferative processes, mainly composed of mycosis fungoides and Sézary syndrome, the aggressive forms of which lack an effective treatment. The molecular pathogenesis of CTCL is largely unknown, although neoplastic cells show increased signaling from T-cell receptors (TCRs). DNAs from 11 patients with CTCL, both normal and tumoral, were target-enriched and sequenced by massive parallel sequencing for a selection of 524 TCR-signaling-related genes. Identified variants were validated by capillary sequencing. Multiple mutations were found that affected several signaling pathways, such as TCRs, nuclear factor κB, or Janus kinase/signal transducer and activator of transcription, but PLCG1 was found to be mutated in 3 samples, 2 of which featured a redundant mutation (c.1034T>C, S345F) in exon 11 that affects the PLCx protein catalytic domain. This mutation was further analyzed by quantitative polymerase chain reaction genotyping in a new cohort of 42 patients with CTCL, where it was found in 19% of samples. Immunohistochemical analysis for nuclear factor of activated T cells (NFAT) showed that PLCG1-mutated cases exhibited strong NFAT nuclear immunostaining. Functional studies demonstrated that PLCG1 mutants elicited increased downstream signaling toward NFAT activation, and inhibition of this pathway resulted in reduced CTCL cell proliferation and cell viability. Thus, increased proliferative and survival mechanisms in CTCL may partially depend on the acquisition of somatic mutations in PLCG1 and other genes that are essential for normal T-cell differentiation.


Assuntos
Linfoma de Células T/genética , Mutação , Fosfolipase C gama/genética , Neoplasias Cutâneas/genética , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Estudos de Coortes , Análise Mutacional de DNA , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Linfoma de Células T/patologia , Masculino , Camundongos , Células NIH 3T3 , Neoplasias Cutâneas/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...