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1.
J Biol Chem ; 290(45): 27261-27270, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26359499

RESUMO

JAK (Janus family of cytoplasmic tyrosine kinases) family tyrosine kinase 2 (TYK2) participates in signaling through cytokine receptors involved in immune responses and inflammation. JAKs are characterized by dual kinase domain: a tyrosine kinase domain (JH1) that is preceded by a pseudokinase domain (JH2). The majority of disease-associated mutations in JAKs map to JH2, demonstrating its central regulatory function. JH2s were considered catalytically inactive, but JAK2 JH2 was found to have low autoregulatory catalytic activity. Whether the other JAK JH2s share ATP binding and enzymatic activity has been unclear. Here we report the crystal structure of TYK2 JH2 in complex with adenosine 5'-O-(thiotriphosphate) (ATP-γS) and characterize its nucleotide binding by biochemical and biophysical methods. TYK2 JH2 did not show phosphotransfer activity, but it binds ATP and the nucleotide binding stabilizes the protein without inducing major conformational changes. Mutation of the JH2 ATP-binding pocket increased basal TYK2 phosphorylation and downstream signaling. The overall structural characteristics of TYK2 JH2 resemble JAK2 JH2, but distinct stabilizing molecular interactions around helix αAL in the activation loop provide a structural basis for differences in substrate access and catalytic activities among JAK family JH2s. The structural and biochemical data suggest that ATP binding is functionally important for both TYK2 and JAK2 JH2s, whereas the regulatory phosphorylation appears to be a unique property of JAK2. Finally, the co-crystal structure of TYK2 JH2 complexed with a small molecule inhibitor demonstrates that JH2 is accessible to ATP-competitive compounds, which offers novel approaches for targeting cytokine signaling as well as potential therapeutic applications.


Assuntos
TYK2 Quinase/química , TYK2 Quinase/metabolismo , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Cristalografia por Raios X , Ativação Enzimática , Estabilidade Enzimática , Humanos , Janus Quinase 1/química , Janus Quinase 2/química , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Fosforilação , Conformação Proteica , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , Homologia Estrutural de Proteína , TYK2 Quinase/genética
2.
Int J Clin Oncol ; 21(6): 1062-1070, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27380168

RESUMO

BACKGROUND: Extensive-stage small cell lung cancer (ESCLC) includes metastatic disease and locally advanced disease confined to the thorax that cannot be encompassed in a typical radiation portal. We assessed and then compared the benefits of thoracic radiotherapy (TRT) and/or brain radiotherapy (BRT) on overall survival (OS) between the intrathoracic (T-ESCLC) and metastatic (M-ESCLC) groups using the Surveillance Epidemiology and End Results database. METHODS: TRT and BRT data were available for 10150 patients treated from 1988-1997. The T-ESCLC group included 1774 patients. The Kaplan-Meier method was used to estimate OS and the proportional hazards model was used to estimate OS hazard ratios for prognostic factors including age, gender, race, tumor size, T/N stage, TRT, and BRT. RESULTS: The 2-year OS for T-ESCLC was 7.8 % compared to 3 % in the M-ESCLC group (p < 0.001). In the T-ESCLC group, TRT and BRT were delivered to 750 and 102 patients, respectively. The 2-year OS was 13 % in the TRT group compared to 4.1 % in the no-TRT group (p ≤ 0.001) and 22.5 % in the BRT group compared to 7 % in the no-BRT group (p < 0.001). In the M-ESCLC group, TRT and BRT were delivered to 3093 and 1887 patients, respectively. The 2-year OS was 4.4 % in the TRT group compared to 2.8 % in the no-TRT group (p < 0.001) and 4.3 % in the BRT compared to 2.6 % in the no-BRT group (p < 0.001). Age, gender, TRT and BRT were significant OS prognostic factors in both groups. CONCLUSIONS: Our study suggests that T-ESCLC is a disease entity distinct from M-ESCLC. Prospective studies to determine whether TRT should be recommended for the thoracic-only subgroup are warranted.


Assuntos
Neoplasias Encefálicas , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Avaliação de Processos e Resultados em Cuidados de Saúde , Prognóstico , Estudos Prospectivos , Radioterapia/métodos , Estudos Retrospectivos , Programa de SEER/estatística & dados numéricos , Carcinoma de Pequenas Células do Pulmão/mortalidade , Carcinoma de Pequenas Células do Pulmão/patologia , Carcinoma de Pequenas Células do Pulmão/radioterapia , Estados Unidos/epidemiologia
3.
Am J Clin Oncol ; 39(2): 120-5, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24390276

RESUMO

INTRODUCTION: We investigated the relationships between treatment characteristics and long-term outcomes in patients with locally advanced thymoma or thymic carcinoma. METHODS: We retrospectively reviewed 146 patients treated from 1980 to 2011 at 2 tertiary cancer care centers, 110 with Masaoka-Koga stages III to IVA invasive thymoma and 36 with stages I to IVA thymic carcinoma. Survival probabilities were estimated using the Kaplan-Meier method. Risk factors related to survival were identified by univariate and multivariate competing risk analysis, with overall survival (OS) as the competing risk. The Cox regression analysis was used to identify risk factors for OS. RESULTS: Median follow-up time for all patients was 64 months. At 5 and 10 years, rates of OS and freedom from recurrence (FFR) were 81% and 58% and 81% and 65%, respectively. Of the patients who underwent surgery, trimodality treatment produced better survival compared with less aggressive treatment among patients with stage III disease (P=0.03). Among patients who underwent trimodality treatment, patients with stage III disease had better OS (P=0.03) and FFR (P<0.001) than those with stage IVA disease. On Cox regression analysis, decreased OS was associated with thymic carcinoma (hazard ratio [HR], 7.36; 95% confidence interval [CI], 2.38-22.77; P=0.001), R2/unresectable disease (HR, 8.45; 95% CI, 1.44-49.42; P=0.02), and an Eastern Cooperative Oncology Group performance score of 1 (HR, 8.14; 95% CI, 1.55-42.75; P=0.01) or 2 to 3 (HR, 29.60; 95% CI, 4.0-218.98; P=0.001) versus 0. CONCLUSIONS: Aggressive treatment with chemotherapy, surgical resection, and postoperative radiation therapy can produce long-term survival for patients with invasive thymic malignancies.


Assuntos
Timoma/terapia , Neoplasias do Timo/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos , Terapia Combinada , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Radioterapia , Estudos Retrospectivos , Timectomia , Timoma/mortalidade , Neoplasias do Timo/mortalidade , Resultado do Tratamento , Adulto Jovem
4.
Clin Transl Radiat Oncol ; 1: 9-14, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29657988

RESUMO

PURPOSE: We assessed outcomes after proton therapy (PT) for central nervous system germinomas or non-germinomatous germ cell tumors (NGGCTs) in children. PATIENTS AND METHODS: We identified children with germ cell tumors of the central nervous system who received proton therapy in 2006-2009 and extracted information on tumor response, treatment failures, and toxicity. RESULTS: Of the 20 identified patients (median age 12 years [range 3-16]), 9 had germinoma and 11 NGGCTs; 19 patients received three-dimensional conformal PT and 1 scanning-beam PT. Fourteen patients had craniospinal irradiation (CSI), 4 had ventricular irradiation that excluded the 4th ventricle, and 2 had whole-ventricle irradiation. All received involved-field boosts. At a median follow-up interval of 5.6 years (range, 0.3-8.2 years), 1 patient with germinoma had an out-of-field failure in the 4th ventricle and 2 with NGGCT died from disease progression after CSI. Rates of local control, progression-free survival, and overall survival at 5 years were 89%, 89%, and 100% for patients with germinoma; corresponding rates for NGGCTs were 82%, 82%, and 82%. The most common late toxicity (9 patients [45%]) was endocrinopathy. CONCLUSIONS: PT for CNS germ cell tumors is associated with acceptable disease control rates and toxicity profiles.

5.
Radiother Oncol ; 114(2): 224-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25542650

RESUMO

PURPOSE: To report long-term progression-free survival (PFS) and late-toxicity outcomes in pediatric craniopharyngioma patients treated with IMRT. PATIENTS AND METHODS: Twenty-four children were treated with IMRT to a median dose of 50.4Gy (range, 49.8-54Gy). The clinical target volume (CTV) was the gross tumor volume (GTV) with a 1cm margin. The planning target volume (PTV) was the CTV with a 3-5mm margin. Median follow-up was 107.3months. RESULTS: The 5- and 10-year PFS rates were 65.8% and 60.7%. The 5- and 10-year cystic PFS rates were 70.2% and 65.2% while the 5- and 10-year solid PFS were the same at 90.7%. Endocrinopathy was seen in 42% at initial diagnosis and in 74% after surgical intervention, prior to IMRT. Hypothalamic dysfunction and visual deficits were associated with increasing PTV and number of surgical interventions. CONCLUSIONS: IMRT is a viable treatment option for pediatric craniopharyngioma. Despite the use of IMRT, majority of the craniopharyngioma patients experienced long-term toxicity, many of which present prior to radiotherapy. Limitations of retrospective analyses on small patient cohort elicit the need for a prospective multi-institutional study to determine the absolute benefit of IMRT in pediatric craniopharyngioma.


Assuntos
Craniofaringioma/radioterapia , Craniofaringioma/cirurgia , Neoplasias Hipofisárias/radioterapia , Neoplasias Hipofisárias/cirurgia , Adolescente , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Lesões por Radiação/diagnóstico , Lesões por Radiação/etiologia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
6.
Int J Radiat Oncol Biol Phys ; 90(2): 354-61, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25052561

RESUMO

PURPOSE: We compared proton beam therapy (PBT) with intensity modulated radiation therapy (IMRT) for pediatric craniopharyngioma in terms of disease control, cyst dynamics, and toxicity. METHODS AND MATERIALS: We reviewed records from 52 children treated with PBT (n=21) or IMRT (n=31) at 2 institutions from 1996-2012. Endpoints were overall survival (OS), disease control, cyst dynamics, and toxicity. RESULTS: At 59.6 months' median follow-up (PBT 33 mo vs IMRT 106 mo; P<.001), the 3-year outcomes were 96% for OS, 95% for nodular failure-free survival and 76% for cystic failure-free survival. Neither OS nor disease control differed between treatment groups (OS P=.742; nodular failure-free survival P=.546; cystic failure-free survival P=.994). During therapy, 40% of patients had cyst growth (20% requiring intervention); immediately after therapy, 17 patients (33%) had cyst growth (transient in 14), more commonly in the IMRT group (42% vs 19% PBT; P=.082); and 27% experienced late cyst growth (32% IMRT, 19% PBT; P=.353), with intervention required in 40%. Toxicity did not differ between groups. On multivariate analysis, cyst growth was related to visual and hypothalamic toxicity (P=.009 and .04, respectively). Patients given radiation as salvage therapy (for recurrence) rather than adjuvant therapy had higher rates of visual and endocrine (P=.017 and .024, respectively) dysfunction. CONCLUSIONS: Survival and disease-control outcomes were equivalent for PBT and IMRT. Cyst growth is common, unpredictable, and should be followed during and after therapy, because it contributes to late toxicity. Delaying radiation therapy until recurrence may result in worse visual and endocrine function.


Assuntos
Craniofaringioma/radioterapia , Neoplasias Hipofisárias/radioterapia , Terapia com Prótons/métodos , Radioterapia de Intensidade Modulada/métodos , Criança , Craniofaringioma/mortalidade , Progressão da Doença , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Neoplasias Hipofisárias/mortalidade , Terapia com Prótons/efeitos adversos , Terapia com Prótons/mortalidade , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/mortalidade , Resultado do Tratamento
7.
Int J Radiat Oncol Biol Phys ; 83(5): 1374-80, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22209153

RESUMO

PURPOSE: To evaluate the feasibility, implementation, and early results of noninvasive breast brachytherapy (NIBB) for tumor bed boost with whole breast radiation therapy (WBRT). METHODS AND MATERIALS: NIBB is a commercially available (AccuBoost, Billerica, MA) mammography-based, brachytherapy system in which the treatment applicators are centered on the planning target volume (PTV) to direct (192)Ir emissions along orthogonal axes. A privacy-encrypted online data registry collected information from 8 independent academic and community-based institutions. Data were from 146 consecutive women with early-stage breast cancer after lumpectomy and WBRT receiving boost with NIBB between July 2007 and March 2010. Toxicity and cosmesis were graded according to the Common Toxicity Criteria (v. 3.0) and the Harvard scale. Median follow-up was 6 months (1-39 months). RESULTS: Grade 1-2 skin toxicity was observed in 64%, 48%, and 21% during the acute (1-3 weeks), intermediate (4-26 weeks), and late-intermediate (>26 weeks) periods. There was no Grade 4 toxicity. At 6 months, for the entire cohort, cosmesis was excellent/good in 62%/38%. The subset receiving NIBB before WBRT had cosmetic scores of 32% and 63%, whereas during WBRT, 58% and 37% were rated as excellent and good, respectively. Breast compression was scored as "uncomfortable" in 12%, 29%, and 59% when NIBB was delivered before, during, or after WBRT. For each patient, the fraction-to-fraction variability in PTV was low. Skin flash was associated with a higher proportion of excellent cosmesis (58% vs. 42%) relative to having the applicator all within breast tissue. CONCLUSIONS: These data indicate that NIBB is feasible and can be consistently implemented in a broad array of practice settings. Preliminary evaluation suggests that NIBB is associated with acceptably mild normal tissue toxicity and favorable early cosmesis. The application of NIBB before WBRT may be associated with better patient tolerance at the expense of less favorable cosmetic outcome.


Assuntos
Braquiterapia/métodos , Neoplasias da Mama/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/efeitos adversos , Mama/efeitos da radiação , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma in Situ/patologia , Carcinoma in Situ/radioterapia , Carcinoma in Situ/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/radioterapia , Carcinoma Ductal de Mama/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Radioisótopos de Irídio/uso terapêutico , Mastectomia Segmentar , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Lesões por Radiação/patologia , Radioterapia Adjuvante/efeitos adversos , Radioterapia Adjuvante/métodos , Pele/efeitos da radiação , Resultado do Tratamento
8.
Immunogenetics ; 58(2-3): 81-8, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16470377

RESUMO

NKG2D is a homodimeric C-type lectin-related receptor expressed on natural killer (NK) cells and T cells. In mice, alternative deoxyribonucleic acid (DNA) splicing generates two isoforms of NKG2D that differ in the length of their cytoplasmic domains. Their ability to induce cellular activation is mediated via association with two membrane-bound, signaling adaptor molecules, DAP10 and DAP12. It has been reported that the long form of NKG2D associates exclusively with DAP10, whereas the short variant can interact with either adaptor. The short isoform was reported to be almost undetectable in naive NK cells. Using two distinct cell types, we demonstrate that like the short isoform, the long variant of NKG2D also associates not only with DAP10 but also with DAP12. Using reporter cells (70Z/3), we demonstrate that DAP12 can compete equally with DAP10 for association with both variants of NKG2D when DAP10 and DAP12 are coexpressed. Cross-linking either isoform of NKG2D induces a calcium flux when associated exclusively with DAP10 or DAP12. Moreover, using quantitative polymerase chain reaction (PCR), we also show that the short isoform of NKG2D is expressed in naive NK cells. Our data suggest that signaling via mouse NKG2D isoforms is more complex than originally presented.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Células Matadoras Naturais/imunologia , Proteínas de Membrana/metabolismo , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Processamento Alternativo , Animais , Linhagem Celular , Células Matadoras Naturais/metabolismo , Camundongos , Subfamília K de Receptores Semelhantes a Lectina de Células NK , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores de Células Matadoras Naturais , Recombinação Genética
9.
J Immunol ; 169(12): 6711-9, 2002 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-12471102

RESUMO

The putative counterparts of human plasmacytoid pre-dendritic cells (pDCs) have been described in vivo in mouse models and very recently in an in vitro culture system. In this study, we report that large numbers of bone marrow-derived murine CD11c(+)B220(+) pDCs can be generated with Flt3 ligand (FL) as the sole exogenous differentiation/growth factor and that pDC generation is regulated in vivo by FL because FL-deficient mice showed a major reduction in splenic pDC numbers. We extensively analyzed bone marrow-derived CD11c(+)B220(+) pDCs and described their immature APC phenotype based on MHC class II, activation markers, and chemokine receptor level of expression. CD11c(+)B220(+) pDCs showed a nonoverlapping Toll-like receptor pattern of expression distinct from that of classical CD11c(+)B220(-) dendritic cells and were poor T cell stimulators. Stimulation of CD11c(+)B220(+) pDCs with oligodeoxynucleotides containing certain CpG motifs plus CD40 ligand plus GM-CSF led to increased MHC class II, CD80, CD86, and CD8alpha expression levels, to a switch in chemokine receptor expression that affected their migration, to IFN-alpha and IL-12 secretion, and to the acquisition of priming capacities for both CD4(+) and CD8(+) OVA-specific TCR-transgenic naive T cells. Thus, the in vitro generation of murine pDCs may serve as a useful tool to further investigate pDC biology as well as the potential role of these cells in viral immunity and other settings.


Assuntos
Células Apresentadoras de Antígenos/citologia , Células da Medula Óssea/citologia , Células Dendríticas/citologia , Proteínas de Drosophila , Substâncias de Crescimento/fisiologia , Proteínas de Membrana/fisiologia , Células-Tronco/citologia , Células-Tronco/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Antígeno CD11c/biossíntese , Antígenos CD8/biossíntese , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Divisão Celular/genética , Divisão Celular/imunologia , Movimento Celular/imunologia , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Feminino , Substâncias de Crescimento/deficiência , Substâncias de Crescimento/genética , Imunofenotipagem , Interferon-alfa/metabolismo , Interleucina-12/metabolismo , Antígenos Comuns de Leucócito/biossíntese , Glicoproteínas de Membrana/biossíntese , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptores de Superfície Celular/biossíntese , Células-Tronco/metabolismo , Receptores Toll-Like
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