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1.
Nat Commun ; 11(1): 912, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-32060266

RESUMO

Progressive ventricular enlargement, a key feature of several neurologic and psychiatric diseases, is mediated by unknown mechanisms. Here, using murine models of 22q11-deletion syndrome (22q11DS), which is associated with schizophrenia in humans, we found progressive enlargement of lateral and third ventricles and deceleration of ciliary beating on ependymal cells lining the ventricular walls. The cilia-beating deficit observed in brain slices and in vivo is caused by elevated levels of dopamine receptors (Drd1), which are expressed in motile cilia. Haploinsufficiency of the microRNA-processing gene Dgcr8 results in Drd1 elevation, which is brought about by a reduction in Drd1-targeting microRNAs miR-382-3p and miR-674-3p. Replenishing either microRNA in 22q11DS mice normalizes ciliary beating and ventricular size. Knocking down the microRNAs or deleting their seed sites on Drd1 mimicked the cilia-beating and ventricular deficits. These results suggest that the Dgcr8-miR-382-3p/miR-674-3p-Drd1 mechanism contributes to deceleration of ciliary motility and age-dependent ventricular enlargement in 22q11DS.


Assuntos
Ventrículos Cerebrais/metabolismo , Cílios/fisiologia , MicroRNAs/genética , Esquizofrenia/genética , Animais , Deleção Cromossômica , Cílios/genética , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Receptores Dopaminérgicos/genética , Receptores Dopaminérgicos/metabolismo , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatologia
2.
Cell Rep ; 30(2): 454-464.e5, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31940489

RESUMO

Loss of heterozygosity (LOH) at 1p36 occurs in multiple cancers, including neuroblastoma (NBL). MYCN amplification and 1p36 deletions tightly correlate with markers of tumor aggressiveness in NBL. Although distal 1p36 losses associate with single-copy MYCN tumors, larger deletions correlate with MYCN amplification, indicating two tumor suppressor regions in 1p36, only one of which facilitates MYCN oncogenesis. To better define this region, we genome-edited the syntenic 1p36 locus in primary mouse neural crest cells (NCCs), a putative NBL cell of origin. In in vitro cell transformation assays, we show that Chd5 loss confers most of the MYCN-independent tumor suppressor effects of 1p36 LOH. In contrast, MYCN-driven tumorigenesis selects for NCCs with Arid1a deletions from a pool of NCCs with randomly sized 1p36 deletions, establishing Arid1a as the MYCN-associated tumor suppressor. Our findings reveal that Arid1a loss collaborates with oncogenic MYCN and better define the tumor suppressor functions of 1p36 LOH in NBL.

3.
Nature ; 576(7787): 471-476, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31827283

RESUMO

Adoptive cell therapy represents a new paradigm in cancer immunotherapy, but it can be limited by the poor persistence and function of transferred T cells1. Here we use an in vivo pooled CRISPR-Cas9 mutagenesis screening approach to demonstrate that, by targeting REGNASE-1, CD8+ T cells are reprogrammed to long-lived effector cells with extensive accumulation, better persistence and robust effector function in tumours. REGNASE-1-deficient CD8+ T cells show markedly improved therapeutic efficacy against mouse models of melanoma and leukaemia. By using a secondary genome-scale CRISPR-Cas9 screening, we identify BATF as the key target of REGNASE-1 and as a rheostat that shapes antitumour responses. Loss of BATF suppresses the increased accumulation and mitochondrial fitness of REGNASE-1-deficient CD8+ T cells. By contrast, the targeting of additional signalling factors-including PTPN2 and SOCS1-improves the therapeutic efficacy of REGNASE-1-deficient CD8+ T cells. Our findings suggest that T cell persistence and effector function can be coordinated in tumour immunity and point to avenues for improving the efficacy of adoptive cell therapy for cancer.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Imunoterapia Adotiva/métodos , Leucemia/imunologia , Leucemia/terapia , Melanoma/imunologia , Melanoma/terapia , Terapia de Alvo Molecular , Ribonucleases/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina Básica/deficiência , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Linfócitos T CD8-Positivos/citologia , Sistemas CRISPR-Cas/genética , Modelos Animais de Doenças , Feminino , Deleção de Genes , Humanos , Leucemia/genética , Leucemia/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Melanoma/genética , Melanoma/metabolismo , Camundongos , Mitocôndrias/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 2/genética , Proteína Tirosina Fosfatase não Receptora Tipo 2/metabolismo , Reprodutibilidade dos Testes , Ribonucleases/deficiência , Ribonucleases/genética , Ribonucleases/imunologia , Proteína 1 Supressora da Sinalização de Citocina/genética , Proteína 1 Supressora da Sinalização de Citocina/metabolismo , Microambiente Tumoral/imunologia
4.
J Environ Radioact ; 208-209: 106036, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31493563

RESUMO

In order to develop an artificially constructed plant community plot for the enhanced phytoremediation of uranium contaminated soils, three uranium accumulators including Bamboo-willow (Salix sp.), Paspalum scrobiculatum linn and Macleaya cordata were used to construct four artificial plant community plots, and greenhouse experiments were conducted to investigate the bioaccumulation of uranium by the plants and the organic acid content, enzyme activity, and the change of microbial community structure in their rhizosphere soils. The transfer factor (TF) and the total bioaccumulation amount (TBA) of uranium were used to describe remediation efficiencies in this paper. It was found that their remediation efficiencies were in the order Bamboo-willow (Salix sp.)-Paspalum scrobiculatum linn-Macleaya cordata > Bamboo-willow (Salix sp.)-Macleaya cordata > Paspalum scrobiculatum linn-Macleaya cordata > Bamboo-willow (Salix sp.)-Paspalum scrobiculatum linn. The bioaccumulation amount of uranium by each plant in the Bamboo-willow (Salix sp.)-Paspalum scrobiculatum linn-Macleaya cordata community plot was significantly (P < 0.05) higher than that by its single population, the bioaccumulation amounts of uranium by Bamboo-willow (Salix sp.), Paspalum scrobiculatum linn and Macleaya cordata were 0.29, 0.32 and 2.19 mg/plant, respectively, and they were increased by 31.82%, 77.78% and 146.07%, respectively, and the transfer efficiencies by the plants were increased by 150%, 110% and 52.17%, respectively. The interaction between the plants' roots and the microorganisms in the rhizosphere soil of the Bamboo-willow (Salix sp.)-Paspalum scrobiculatum linn-Macleaya cordata community plot resulted in the high content of organic acids such as oxalic acid in the rhizosphere soil of the plant community plot, which was significantly (P < 0.05) higher than that of its single population. The chelation of the organic acids with uranium led to an increase in the proportion of exchangeable uranium in soil solution. In addition, Burkholderia, which is an iron-producing carrier bacterium and can increase the uptake and accumulation of uranium by plants, and Leptolyngbya, which is a plant growth promoting rhizobacteria and can increase the biomass of plants, emerged in the rhizosphere soil of the plant community plot. These may be the mechanisms by which the phytoremediation of the uranium contaminated soils was enhanced by the plant community plot.


Assuntos
Biodegradação Ambiental , Poluentes Radioativos do Solo/metabolismo , Urânio/metabolismo
5.
Clin Cancer Res ; 25(24): 7320-7330, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31455680

RESUMO

PURPOSE: To determine the pharmacokinetics and skin toxicity profile of sorafenib in children with refractory/relapsed malignancies. PATIENTS AND METHODS: Sorafenib was administered concurrently or sequentially with clofarabine and cytarabine to patients with leukemia or with bevacizumab and cyclophosphamide to patients with solid tumor malignancies. The population pharmacokinetics (PPK) of sorafenib and its metabolites and skin toxicities were evaluated. RESULTS: In PPK analysis, older age, bevacizumab and cyclophosphamide regimen, and higher creatinine were associated with decreased sorafenib apparent clearance (CL/f; P < 0.0001 for all), and concurrent clofarabine and cytarabine administration was associated with decreased sorafenib N-oxide CL/f (P = 7e-4). Higher bilirubin was associated with decreased sorafenib N-oxide and glucuronide CL/f (P = 1e-4). Concurrent use of organic anion-transporting polypeptide 1B1 inhibitors was associated with increased sorafenib and decreased sorafenib glucuronide CL/f (P < 0.003). In exposure-toxicity analysis, a shorter time to development of grade 2-3 hand-foot skin reaction (HFSR) was associated with concurrent (P = 0.0015) but not with sequential (P = 0.59) clofarabine and cytarabine administration, compared with bevacizumab and cyclophosphamide, and with higher steady-state concentrations of sorafenib (P = 0.0004) and sorafenib N-oxide (P = 0.0275). In the Bayes information criterion model selection, concurrent clofarabine and cytarabine administration, higher sorafenib steady-state concentrations, larger body surface area, and previous occurrence of rash appeared in the four best two-predictor models of HFSR. Pharmacokinetic simulations showed that once-daily and every-other-day sorafenib schedules would minimize exposure to sorafenib steady-state concentrations associated with HFSR. CONCLUSIONS: Sorafenib skin toxicities can be affected by concurrent medications and sorafenib steady-state concentrations. The described PPK model can be used to refine exposure-response relations for alternative dosing strategies to minimize skin toxicity.

6.
Clin Transl Sci ; 12(6): 641-647, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31350825

RESUMO

Fms-like tyrosine kinase 3 (FLT3) internal tandem duplication (ITD) mutations, common in pediatric acute myeloid leukemia (AML), associate with early relapse and poor prognosis. Past studies have suggested additional cooperative mutations are required for leukemogenesis in FLT3-ITD+ AML. Using RNA sequencing and a next-generation targeted gene panel, we broadly characterize the co-occurring genomic alterations in pediatric cytogenetically normal (CN) FLT3-ITD+ AML to gain a deeper understanding of the clonal patterns and heterogeneity at diagnosis and relapse. We show that chimeric transcripts were present in 21 of 34 (62%) of de novo samples, 2 (6%) of these samples included a rare reoccurring fusion partner BCL11B. At diagnosis, the median number of mutations other than FLT3 per patient was 1 (range 0-3), which involved 8 gene pathways; WT1 and NPM1 mutations were frequently observed (35% and 24%, respectively). Fusion transcripts and high variant allele frequency (VAF) mutants, which included WT1, NPM1, SMARCA2, RAD21, and TYK2, were retained from diagnosis to relapse. We did observe reduction in VAF of simple or single mutation clones, but VAFs were preserved or expanded in more complex clones with multiple mutations. Our data provide the first insight into the genomic complexity of pediatric CN FLT3-ITD+ AML and could help stratify future targeted treatment strategies.

7.
Genome Res ; 29(8): 1262-1276, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31249065

RESUMO

Organisms use endogenous clocks to adapt to the rhythmicity of the environment and to synchronize social activities. Although the circadian cycle is implicated in aging, it is unknown whether natural variation in its function contributes to differences in lifespan between populations and whether the circadian clock of specific tissues is key for longevity. We have sequenced the genomes of Drosophila melanogaster strains with exceptional longevity that were obtained via multiple rounds of selection from a parental strain. Comparison of genomic, transcriptomic, and proteomic data revealed that changes in gene expression due to intergenic polymorphisms are associated with longevity and preservation of skeletal muscle function with aging in these strains. Analysis of transcription factors differentially modulated in long-lived versus parental strains indicates a possible role of circadian clock core components. Specifically, there is higher period and timeless and lower cycle expression in the muscle of strains with delayed aging compared to the parental strain. These changes in the levels of circadian clock transcription factors lead to changes in the muscle circadian transcriptome, which includes genes involved in metabolism, proteolysis, and xenobiotic detoxification. Moreover, a skeletal muscle-specific increase in timeless expression extends lifespan and recapitulates some of the transcriptional and circadian changes that differentiate the long-lived from the parental strains. Altogether, these findings indicate that the muscle circadian clock is important for longevity and that circadian gene variants contribute to the evolutionary divergence in longevity across populations.


Assuntos
Fatores de Transcrição ARNTL/genética , Relógios Circadianos/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Genoma de Inseto , Longevidade/genética , Músculo Esquelético/metabolismo , Proteínas Circadianas Period/genética , Fatores de Transcrição ARNTL/metabolismo , Animais , Evolução Biológica , Ritmo Circadiano/genética , DNA Intergênico/genética , DNA Intergênico/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Genética Populacional , Genômica , Músculo Esquelético/crescimento & desenvolvimento , Proteínas Circadianas Period/metabolismo , Polimorfismo Genético , Transcriptoma , Sequenciamento Completo do Genoma
8.
Nat Prod Res ; : 1-7, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31135188

RESUMO

Six julichrome derivatives including a new monomeric julichrome named as julichrome Q10 (1), and previous reported julichrome Q6 (2), julichrome Q6.6 (4), julichrome Q3.5 (5), julichrome Q5.6 (6), julichrome Q2.3 (7), along with a diketopiperazine gliotoxin (3) were isolated from a soil derived strain Streptomyces sp. The structures of these compounds were identified by HR-ESI-MS, UV, IR and NMR methods. The isolated compounds were tested for their in vitro cytotoxicity against human hepatocarcinoma HepG-2 and SMMC-7721 cell lines, human breast cancer MCF-7 and MDA-MB-231 cell lines, and human normal heptical LO2 cell line. Gliotoxin (3) showed the most cytotoxic activity against the tested tumor cell lines, with IC50 values ranging from 0.11 to 1.45 µM. Julichrome Q6.6 (4) displayed selective cytotoxic activity against SMMC-7721, MCF-7 and MDA-MB-231 cell lines.

9.
Cancer Res ; 79(9): 2208-2219, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30885981

RESUMO

Choroid plexus carcinoma (CPC) is a rare brain tumor that occurs most commonly in very young children and has a dismal prognosis despite intensive therapy. Improved outcomes for patients with CPC depend on a deeper understanding of the mechanisms underlying the disease. Here we developed transgenic models of CPCs by activating the Myc oncogene and deleting the Trp53 tumor suppressor gene in murine neural stem cells or progenitors. Murine CPC resembled their human counterparts at a histologic level, and like the hypodiploid subset of human CPC, exhibited multiple whole-chromosome losses, particularly of chromosomes 8, 12, and 19. Analysis of murine and human CPC gene expression profiles and copy number changes revealed altered expression of genes involved in cell cycle, DNA damage response, and cilium function. High-throughput drug screening identified small molecule inhibitors that decreased the viability of CPC. These models will be valuable tools for understanding the biology of choroid plexus tumors and for testing novel approaches to therapy. SIGNIFICANCE: This study describes new mouse models of choroid plexus carcinoma and uses them to investigate the biology and therapeutic responsiveness of this highly malignant pediatric brain tumor.


Assuntos
Carcinoma/patologia , Neoplasias do Plexo Corióideo/patologia , Células-Tronco Neurais/patologia , Proteínas Proto-Oncogênicas c-myc/fisiologia , Bibliotecas de Moléculas Pequenas/farmacologia , Proteína Supressora de Tumor p53/fisiologia , Animais , Antineoplásicos/farmacologia , Carcinoma/tratamento farmacológico , Carcinoma/genética , Neoplasias do Plexo Corióideo/tratamento farmacológico , Neoplasias do Plexo Corióideo/genética , Ensaios de Triagem em Larga Escala , Camundongos , Camundongos Knockout , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Células Tumorais Cultivadas
10.
Blood ; 133(18): 1927-1942, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-30782612

RESUMO

Although many recent studies describe the emergence and prevalence of "clonal hematopoiesis of indeterminate potential" in aged human populations, a systematic analysis of the numbers of clones supporting steady-state hematopoiesis throughout mammalian life is lacking. Previous efforts relied on transplantation of "barcoded" hematopoietic stem cells (HSCs) to track the contribution of HSC clones to reconstituted blood. However, ex vivo manipulation and transplantation alter HSC function and thus may not reflect the biology of steady-state hematopoiesis. Using a noninvasive in vivo color-labeling system, we report the first comprehensive analysis of the changing global clonal complexity of steady-state hematopoiesis during the natural murine lifespan. We observed that the number of clones (ie, clonal complexity) supporting the major blood and bone marrow hematopoietic compartments decline with age by ∼30% and ∼60%, respectively. Aging dramatically reduced HSC in vivo-repopulating activity and lymphoid potential while increasing functional heterogeneity. Continuous challenge of the hematopoietic system by serial transplantation provoked the clonal collapse of both young and aged hematopoietic systems. Whole-exome sequencing of serially transplanted aged and young hematopoietic clones confirmed oligoclonal hematopoiesis and revealed mutations in at least 27 genes, including nonsense, missense, and deletion mutations in Bcl11b, Hist1h2ac, Npy2r, Notch3, Ptprr, and Top2b.


Assuntos
Envelhecimento/fisiologia , Células Clonais/citologia , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/citologia , Animais , Transplante de Células-Tronco Hematopoéticas , Camundongos
11.
Nat Neurosci ; 22(3): 362-373, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30718900

RESUMO

UTX is a chromatin modifier required for development and neural lineage specification, but how it controls these biological processes is unclear. To determine the molecular mechanisms of UTX, we identified novel UTX protein interaction partners. Here we show that UTX and 53BP1 directly interact and co-occupy promoters in human embryonic stem cells and differentiating neural progenitor cells. Human 53BP1 contains a UTX-binding site that diverges from its mouse homolog by 41%, and disruption of the 53BP1-UTX interaction abrogated human, but not mouse, neurogenesis in vitro. The 53BP1-UTX interaction is required to upregulate key neurodevelopmental genes during the differentiation of human embryonic stem cells into neurons or into cortical organoids. 53BP1 promotes UTX chromatin binding, and in turn H3K27 modifications and gene activation, at a subset of genomic regions, including neurogenic genes. Overall, our data suggest that the 53BP1-UTX interaction supports the activation of key genes required for human neurodevelopment.


Assuntos
Córtex Cerebral/metabolismo , Células-Tronco Embrionárias/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Histona Desmetilases/metabolismo , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Proteínas Nucleares/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Córtex Cerebral/crescimento & desenvolvimento , Feminino , Código das Histonas , Humanos , Masculino , Camundongos Endogâmicos C57BL , Organoides/crescimento & desenvolvimento , Organoides/metabolismo , Regiões Promotoras Genéticas
12.
Acta Neuropathol ; 137(1): 123-137, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30267146

RESUMO

Double minute chromosomes are extrachromosomal circular DNA fragments frequently found in brain tumors. To understand their evolution, we characterized the double minutes in paired diagnosis and relapse tumors from a pediatric high-grade glioma and four adult glioblastoma patients. We determined the full structures of the major double minutes using a novel approach combining multiple types of supporting genomic evidence. Among the double minutes identified in the pediatric patient, only one carrying EGFR was maintained at high abundance in both samples, whereas two others were present in only trace amounts at diagnosis but abundant at relapse, and the rest were found either in the relapse sample only or in the diagnosis sample only. For the EGFR-carrying double minutes, we found a secondary somatic deletion in all copies at relapse, after erlotinib treatment. However, the somatic mutation was present at very low frequency at diagnosis, suggesting potential resistance to the EGFR inhibitor. This mutation caused an in-frame RNA transcript to skip exon 16, a novel transcript isoform absent in EST database, as well as about 700 RNA-seq of normal brains that we reviewed. We observed similar patterns involving longitudinal copy number shift of double minutes in another four pairs (diagnosis/relapse) of adult glioblastoma. Overall, in three of five paired tumor samples, we found that although the same oncogenes were amplified at diagnosis and relapse, they were amplified on different double minutes. Our results suggest that double minutes readily evolve, increasing tumor heterogeneity rapidly. Understanding patterns of double minute evolution can shed light on future therapeutic solutions to brain tumors carrying such variants.


Assuntos
Neoplasias Encefálicas/diagnóstico , Encéfalo/patologia , Glioblastoma/genética , Recidiva Local de Neoplasia/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Criança , Genômica , Glioblastoma/diagnóstico , Glioma/genética , Humanos , Masculino , Mutação/genética , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/genética , Recidiva
13.
Nat Prod Res ; : 1-5, 2018 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-30526052

RESUMO

Phytochemical investigation of the roots of Leontopodium longifolium, led to the isolation of a novel norsesquiterpene, named as longifolactone (1), along with three known diterpenes. The structures of these compounds were elucidated by analysis of HR-ESI-MS, UV, IR and 1D and 2D NMR spectroscopic data. The absolute configuration of the new compound was determined by electronic circular dichroism (ECD) using both experimental and calculated ECD spectra. Furthermore, their anti-inflammatory effects were evaluated in LPS-activated RAW264.7 cells to determine their effects on the release of NO. Longifolactone (1) showed weak cytotoxicity towards two human cancer cell lines.

14.
Oncogene ; 37(15): 1991-2007, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29367756

RESUMO

Rhabdomyosarcoma is the most common soft-tissue sarcoma in childhood and histologically resembles developing skeletal muscle. Alveolar rhabdomyosarcoma (ARMS) is an aggressive subtype with a higher rate of metastasis and poorer prognosis. The majority of ARMS tumors (80%) harbor a PAX3-FOXO1 or less commonly a PAX7-FOXO1 fusion gene. The presence of either the PAX3-FOXO1 or PAX7-FOXO1 fusion gene foretells a poorer prognosis resulting in clinical re-classification as either fusion-positive (FP-RMS) or fusion-negative RMS (FN-RMS). The PAX3/7-FOXO1 fusion genes result in the production of a rogue transcription factors that drive FP-RMS pathogenesis and block myogenic differentiation. Despite knowing the molecular driver of FP-RMS, targeted therapies have yet to make an impact for patients, highlighting the need for a greater understanding of the molecular consequences of PAX3-FOXO1 and its target genes including microRNAs. Here we show FP-RMS patient-derived xenografts and cell lines display a distinct microRNA expression pattern. We utilized both loss- and gain-of function approaches in human cell lines with knockdown of PAX3-FOXO1 in FP-RMS cell lines and expression of PAX3-FOXO1 in human myoblasts and identified microRNAs both positively and negatively regulated by the PAX3-FOXO1 fusion protein. We demonstrate PAX3-FOXO1 represses miR-221/222 that functions as a tumor suppressing microRNA through the negative regulation of CCND2, CDK6, and ERBB3. In contrast, miR-486-5p is transcriptionally activated by PAX3-FOXO1 and promotes FP-RMS proliferation, invasion, and clonogenic growth. Inhibition of miR-486-5p in FP-RMS xenografts decreased tumor growth, illustrating a proof of principle for future therapeutic intervention. Therefore, PAX3-FOXO1 regulates key microRNAs that may represent novel therapeutic vulnerabilities in FP-RMS.


Assuntos
MicroRNAs/genética , Neoplasias Musculares/genética , Proteínas de Fusão Oncogênica/fisiologia , Fatores de Transcrição Box Pareados/fisiologia , Rabdomiossarcoma Alveolar/genética , Animais , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Células Cultivadas , Criança , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Camundongos , Camundongos SCID , Análise em Microsséries , Neoplasias Musculares/patologia , Proteínas de Fusão Oncogênica/genética , Fatores de Transcrição Box Pareados/genética , Rabdomiossarcoma Alveolar/patologia
15.
J Clin Invest ; 128(1): 369-380, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29227282

RESUMO

Oncogenic addiction to the Fms-like tyrosine kinase 3 (FLT3) is a hallmark of acute myeloid leukemia (AML) that harbors the FLT3-internal tandem duplication (FLT3-ITD) mutation. While FLT3 inhibitors like sorafenib show initial therapeutic efficacy, resistance rapidly develops through mechanisms that are incompletely understood. Here, we used RNA-Seq-based analysis of patient leukemic cells and found that upregulation of the Tec family kinase BMX occurs during sorafenib resistance. This upregulation was recapitulated in an in vivo murine FLT3-ITD-positive (FLT3-ITD+) model of sorafenib resistance. Mechanistically, the antiangiogenic effects of sorafenib led to increased bone marrow hypoxia, which contributed to HIF-dependent BMX upregulation. In in vitro experiments, hypoxia-dependent BMX upregulation was observed in both AML and non-AML cell lines. Functional studies in human FLT3-ITD+ cell lines showed that BMX is part of a compensatory signaling mechanism that promotes AML cell survival during FLT3 inhibition. Taken together, our results demonstrate that hypoxia-dependent upregulation of BMX contributes to therapeutic resistance through a compensatory prosurvival signaling mechanism. These results also reveal the role of off-target drug effects on tumor microenvironment and development of acquired drug resistance. We propose that the bone marrow niche can be altered by anticancer therapeutics, resulting in drug resistance through cell-nonautonomous microenvironment-dependent effects.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Regulação Enzimológica da Expressão Gênica , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/metabolismo , Proteínas Tirosina Quinases/biossíntese , Microambiente Tumoral , Regulação para Cima , Hipóxia Celular , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Masculino , Proteínas Tirosina Quinases/genética , Transdução de Sinais , Sorafenibe/farmacologia , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo
16.
Nat Commun ; 8(1): 741, 2017 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-28963450

RESUMO

Many drugs bind to and activate human pregnane X receptor (hPXR) to upregulate drug-metabolizing enzymes, resulting in decreased drug efficacy and increased resistance. This suggests that hPXR antagonists have therapeutic value. Here we report that SPA70 is a potent and selective hPXR antagonist. SPA70 inhibits hPXR in human hepatocytes and humanized mouse models and enhances the chemosensitivity of cancer cells, consistent with the role of hPXR in drug resistance. Unexpectedly, SJB7, a close analog of SPA70, is an hPXR agonist. X-ray crystallography reveals that SJB7 resides in the ligand-binding domain (LBD) of hPXR, interacting with the AF-2 helix to stabilize the LBD for coactivator binding. Differential hydrogen/deuterium exchange analysis demonstrates that SPA70 and SJB7 interact with the hPXR LBD. Docking studies suggest that the lack of the para-methoxy group in SPA70 compromises its interaction with the AF-2, thus explaining its antagonism. SPA70 is an hPXR antagonist and promising therapeutic tool.The xenobiotic-activated human pregnane X receptor (hPXR) regulates drug metabolism. Here the authors develop hPXR modulators, which are of potential therapeutic interest and functionally and structurally characterize the antagonist SPA70 and the structurally related agonist SJB7.


Assuntos
Antagonistas de Hormônios/farmacologia , Receptores de Esteroides/antagonistas & inibidores , Animais , Linhagem Celular , Resistência a Medicamentos , Células HEK293 , Antagonistas de Hormônios/química , Humanos , Camundongos Transgênicos , Modelos Moleculares , Receptor de Pregnano X , Receptores de Esteroides/química
17.
Cell Rep ; 18(12): 2907-2917, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28329683

RESUMO

The most aggressive of four medulloblastoma (MB) subgroups are cMyc-driven group 3 (G3) tumors, some of which overexpress EZH2, the histone H3K27 mono-, di-, and trimethylase of polycomb-repressive complex 2. Ezh2 has a context-dependent role in different cancers as an oncogene or tumor suppressor and retards tumor progression in a mouse model of G3 MB. Engineered deletions of Ezh2 in G3 MBs by gene editing nucleases accelerated tumorigenesis, whereas Ezh2 re-expression reversed attendant histone modifications and slowed tumor progression. Candidate oncogenic drivers suppressed by Ezh2 included Gfi1, a proto-oncogene frequently activated in human G3 MBs. Gfi1 disruption antagonized the tumor-promoting effects of Ezh2 loss; conversely, Gfi1 overexpression collaborated with Myc to bypass effects of Trp53 inactivation in driving MB progression in primary cerebellar neuronal progenitors. Although negative regulation of Gfi1 by Ezh2 may restrain MB development, Gfi1 activation can bypass these effects.


Assuntos
Neoplasias Cerebelares/patologia , Proteínas de Ligação a DNA/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Meduloblastoma/genética , Meduloblastoma/patologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição/genética , Regulação para Cima/genética , Animais , Carcinogênese/metabolismo , Carcinogênese/patologia , Neoplasias Cerebelares/genética , Proteínas de Ligação a DNA/metabolismo , Progressão da Doença , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Camundongos Nus , Mutação/genética , Invasividade Neoplásica , Proteínas de Neoplasias/metabolismo , Oncogenes , Complexo Repressor Polycomb 2/metabolismo , Ligação Proteica , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Fatores de Transcrição/metabolismo
18.
Mol Ther ; 25(3): 593-605, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28190779

RESUMO

Recently, an engineered Homeobox-nucleoporin fusion gene, NUP98-HOXA10HD or NA10HD, was reported to expand and maintain murine hematopoietic stem cells (HSCs). We postulated that NA10HD would increase the number of human γ-globin-expressing cells to therapeutic levels. We developed a double gene lentiviral vector encoding both human γ-globin and NA10HD, which was used to transduce human peripheral blood CD34+ cells and increased engraftment 2- to 2.5-fold at 15 weeks post-transplantation in immunodeficient mice. In ß-thalassemic mice transplanted with ß-thalassemic HSCs transduced with the γ-globin/NA10HD vector, the number of fetal hemoglobin (HbF)-expressing cells was significantly increased after 3 months, leading to resolution of the anemia. Furthermore, the increases in HbF were maintained at 6 months and persisted after secondary transplantation. In addition, NA10HD enrichment of transduced HSCs led to HbF increases without affecting homeostasis of the white blood cell lineages. Our results suggest that NA10HD increases the number of γ-globin-transduced HSCs that engraft, leading to an elevated number of fetal hemoglobin-containing red cells. These effects of NA10HD provide an improved platform for testing of the therapeutic efficacy of novel globin vectors and provide further impetus to develop safe and effective methods for selective expansion of genetically modified cells.


Assuntos
Vetores Genéticos/genética , Células-Tronco Hematopoéticas/metabolismo , Proteínas de Homeodomínio/genética , Lentivirus/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas de Fusão Oncogênica/genética , Talassemia beta/genética , gama-Globinas/genética , Animais , Modelos Animais de Doenças , Eritrócitos/citologia , Eritrócitos/metabolismo , Hemoglobina Fetal/metabolismo , Ordem dos Genes , Técnicas de Transferência de Genes , Loci Gênicos , Sobrevivência de Enxerto , Transplante de Células-Tronco Hematopoéticas , Proteínas Homeobox A10 , Humanos , Camundongos , Transdução Genética , Transplante Heterólogo , Talassemia beta/metabolismo , Talassemia beta/terapia
19.
Nat Med ; 23(1): 39-48, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27892953

RESUMO

Although 22q11.2 deletion syndrome (22q11DS) is associated with early-life behavioral abnormalities, affected individuals are also at high risk for the development of schizophrenia symptoms, including psychosis, later in life. Auditory thalamocortical (TC) projections recently emerged as a neural circuit that is specifically disrupted in mouse models of 22q11DS (hereafter referred to as 22q11DS mice), in which haploinsufficiency of the microRNA (miRNA)-processing-factor-encoding gene Dgcr8 results in the elevation of the dopamine receptor Drd2 in the auditory thalamus, an abnormal sensitivity of thalamocortical projections to antipsychotics, and an abnormal acoustic-startle response. Here we show that these auditory TC phenotypes have a delayed onset in 22q11DS mice and are associated with an age-dependent reduction of miR-338-3p, a miRNA that targets Drd2 and is enriched in the thalamus of both humans and mice. Replenishing depleted miR-338-3p in mature 22q11DS mice rescued the TC abnormalities, and deletion of Mir338 (which encodes miR-338-3p) or reduction of miR-338-3p expression mimicked the TC and behavioral deficits and eliminated the age dependence of these deficits. Therefore, miR-338-3p depletion is necessary and sufficient to disrupt auditory TC signaling in 22q11DS mice, and it may mediate the pathogenic mechanism of 22q11DS-related psychosis and control its late onset.


Assuntos
Córtex Auditivo/fisiopatologia , Vias Auditivas/fisiopatologia , Síndrome de DiGeorge/genética , MicroRNAs/genética , Transtornos Psicóticos/genética , Tálamo/fisiopatologia , Idade de Início , Animais , Antipsicóticos/farmacologia , Córtex Auditivo/efeitos dos fármacos , Córtex Auditivo/metabolismo , Vias Auditivas/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Western Blotting , Síndrome de DiGeorge/fisiopatologia , Síndrome de DiGeorge/psicologia , Modelos Animais de Doenças , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Potenciais Evocados Auditivos do Tronco Encefálico/genética , Deleção de Genes , Haploinsuficiência , Humanos , Camundongos , MicroRNAs/metabolismo , Vias Neurais , Optogenética , Técnicas de Patch-Clamp , Fenótipo , Transtornos Psicóticos/fisiopatologia , Transtornos Psicóticos/psicologia , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Dopamina D2/genética , Reflexo de Sobressalto , Esquizofrenia/metabolismo , Tálamo/efeitos dos fármacos , Tálamo/metabolismo
20.
Environ Sci Pollut Res Int ; 24(6): 5134-5143, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27023802

RESUMO

The endophyte Pseudomonas sp. XNN8 was separated from Typha orientalis which can secrete indole-3-acetic acid and 1-aminocyclopropane-1-carboxylate deaminase and siderophores and has strong resistance to uranium it was then colonized in the Syngonium podophyllum; and the S. podophyllum-Pseudomonas sp. XNN8 symbiotic purification system (SPPSPS) for uranium-containing wastewater was constructed. Afterwards, the hydroponic experiments to remove uranium from uranium-containing wastewater by the SPPSPS were conducted. After 24 days of treatment, the uranium concentrations of the wastewater samples with uranium concentrations between 0.5 and 5.0 mg/L were lowered to below 0.05 mg/L. Furthermore, the uranium in the plants was assayed using Fourier transform infrared spectroscopy (FTIR) and extended X-ray absorption fine structure (EXAFS) spectroscopy. The Pseudomonas sp. XNN8 was found to generate substantial organic groups in the roots of the Syngonium podophyllum, which could improve the complexing capability of S. podophyllum for uranium. The uranium in the roots of S. podophyllum was found to be the uranyl phosphate (47.4 %) and uranyl acetate (52.6 %).


Assuntos
Araceae , Pseudomonas , Urânio , Águas Residuárias , Purificação da Água/métodos , Carbono-Carbono Liases , Hidroponia , Ácidos Indolacéticos , Compostos Organometálicos , Fosfatos , Raízes de Plantas/química , Podophyllum , Espectroscopia de Infravermelho com Transformada de Fourier , Simbiose , Compostos de Urânio , Espectroscopia por Absorção de Raios X
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