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1.
Genes Dev ; 27(8): 916-27, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23630076

RESUMO

Depending on the circumstance, FOXO (Forkhead O) (FOXO1, FOXO3, and FOXO4) transcription factors activate the expression of markedly different sets of genes to produce different phenotypic effects. For example, distinct FOXO-regulated transcriptional programs stimulate cell death or enhance organism life span. To gain insight into how FOXOs select specific genes for regulation, we performed a screen for genes that modify FOXO activation of TRAIL, a death receptor ligand capable of inducing extrinsic apoptosis. We discovered that the bZIP transcriptional repressor NFIL3 (nuclear factor interleukin 3-regulated) hindered FOXO transcription factor access to chromatin at the TRAIL promoter by binding to nearby DNA and recruiting histone deacetylase-2 (HDAC2) to reduce histone acetylation. In the same manner, NFIL3 repressed expression of certain FOXO targets--e.g., FAS, GADD45α (growth arrest and DNA damage-inducible, α), and GADD45ß--but not others. NFIL3, which we found to be overexpressed in different cancers, supported tumor cell survival largely through repression of TRAIL and antagonized hydrogen peroxide-induced cell death. Moreover, its expression in cancer was associated with lower patient survival. Therefore, NFIL3 alters cancer cell behavior and FOXO function by acting on chromatin to restrict the menu of FOXO target genes. Targeting of NFIL3 could be of therapeutic benefit for cancer patients.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , Apoptose/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Sítios de Ligação , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/fisiopatologia , Linhagem Celular Tumoral , Cromatina/metabolismo , Proteína Forkhead Box O1 , Células HEK293 , Histona Desacetilases/metabolismo , Humanos , Estimativa de Kaplan-Meier , Prognóstico , Regiões Promotoras Genéticas , Ligação Proteica , RNA Interferente Pequeno/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/genética
2.
Gynecol Oncol ; 143(2): 379-388, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27614696

RESUMO

OBJECTIVE: Poly(ADP-ribose) polymerase (PARP) inhibitors have yielded encouraging responses in high-grade serous ovarian carcinomas (HGSOCs), but the optimal treatment setting remains unknown. We assessed the effect of niraparib on HGSOC patient-derived xenograft (PDX) models as well as the relationship between certain markers of homologous recombination (HR) status, including BRCA1/2 mutations and formation of RAD51 foci after DNA damage, and response of these PDXs to niraparib in vivo. METHODS: Massively parallel sequencing was performed on HGSOCs to identify mutations contributing to HR deficiency. HR pathway integrity was assessed using fluorescence microscopy-based RAD51 focus formation assays. Effects of niraparib (MK-4827) on treatment-naïve PDX tumor growth as monotherapy, in combination with carboplatin/paclitaxel, and as maintenance therapy were assessed by transabdominal ultrasound. Niraparib responses were correlated with changes in levels of poly(ADP-ribose), PARP1, and repair proteins by western blotting. RESULTS: Five PDX models were evaluated in vivo. Tumor regressions were induced by single-agent niraparib in one of two PDX models with deleterious BRCA2 mutations and in a PDX with RAD51C promoter methylation. Diminished formation of RAD51 foci failed to predict response, but Artemis loss was associated with resistance. Niraparib generally failed to enhance responses to carboplatin/paclitaxel chemotherapy, but maintenance niraparib therapy delayed progression in a BRCA2-deficient PDX. CONCLUSIONS: Mutations in HR genes are neither necessary nor sufficient to predict response to niraparib. Assessment of repair status through multiple complementary assays is needed to guide PARP inhibitor therapy, design future clinical trials and identify ovarian cancer patients most likely to benefit from PARP inhibition.


Assuntos
Recombinação Homóloga , Indazóis/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Piperidinas/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Proteínas de Ligação a DNA/análise , Proteínas de Ligação a DNA/genética , Feminino , Genes BRCA2 , Humanos , Neoplasias Ovarianas/genética , Regiões Promotoras Genéticas
3.
J Environ Health ; 78(8): 8-11, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27188066

RESUMO

During the summer of 2014 an outbreak of tickborne relapsing fever (TBRF) occurred in a group of high school students and staff at a youth camp, which was reported to Coconino County Public Health Services District. Six confirmed and five probable cases of TBRF occurred. During the environmental investigation two rodents tested positive for TBRF, but the vector, soft ticks, could not be found in their "normal" habitat. Ticks were finally located in areas not typical for soft ticks.


Assuntos
Ecossistema , Saúde Ambiental , Ornithodoros/fisiologia , Febre Recorrente/epidemiologia , Adolescente , Distribuição Animal , Animais , Arizona/epidemiologia , Borrelia/fisiologia , Surtos de Doenças , Humanos , Febre Recorrente/parasitologia
4.
Blood Adv ; 6(9): 2745-2756, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35100356

RESUMO

Recent first-line randomized controlled trials (RCTs) for patients with diffuse large B-cell lymphoma (DLBCL) have shown negative results, which may be due in part to onerous eligibility criteria limiting enrollment of poor-risk patients who require immediate treatment. We conducted a Delphi-method survey with lymphoma experts in the United States to define recommendations for essential and potentially unnecessary enrollment criteria for modern first-line DLBCL RCTs aimed at increasing clinical diversity of ensuing study groups. We first tabulated enrollment criteria from 19 DLBCL RCTs spanning the rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) era to identify common eligibility criteria from prior DLBCL RCTs for inclusion in the Delphi-method survey. We tabulated 451 total eligibility criteria comprising 51 criterion categories across 19 first-line DLBCL RCTs in the R-CHOP era. We then surveyed lymphoma clinical trial experts representing 8 academic medical centers in the United States regarding essential and unnecessary eligibility criteria for modern DLBCL RCTs. Seventeen of 29 invited clinical investigators completed the round-1 questionnaire (response rate, of 58.6%), 15 of 17 round-1 participants (88.2%) completed the round-2 survey, and all round-1 participants reviewed finalized recommendations for eligibility criteria for modern first-line DLBCL RCTs. We defined consensus recommendations for 31 modernized eligibility criteria including threshold values for 10 quantitative eligibility criteria aimed at facilitating enrollment of a clinically diverse study population in first-line DLBCL RCTs designed to improve standard-of-care therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Linfoma Difuso de Grandes Células B , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida , Doxorrubicina , Humanos , Linfoma Difuso de Grandes Células B/patologia , Prednisona/efeitos adversos , Prednisona/uso terapêutico , Rituximab , Inquéritos e Questionários , Vincristina
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