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1.
Cancer Nurs ; 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37801588

RESUMO

BACKGROUND: Mindfulness and qigong are 2 distinct forms of mind-body practice that have been well-received by cancer survivors. Although there is evidence supporting the effectiveness of mindfulness or qigong in promoting wellness of cancer survivors, little is known about the differential benefits of these common forms of mind-body practices among survivors. OBJECTIVE: To compare the potential biopsychosocial-spiritual impacts of mindfulness and Baduanjin (BDJ) qigong on colorectal cancer survivors. METHODS: Sixty cancer survivors who participated in a mindfulness intervention (n = 38) and BDJ qigong (n = 22) intervention were invited to provide qualitative feedback for their experiences. Content analyses were conducted to identify emerging themes from the data, and χ2 tests were conducted to compare the responses of the mindfulness and BDJ groups in the major categories. RESULTS: Both practices positively influenced psychosocial wellness. The practice of BDJ qigong led to more prominent improvements in physical well-being, whereas mindfulness worked best in enhancing spiritual growth and intrapersonal connectedness. CONCLUSIONS: Survivors of colorectal cancer who are looking for ways to enhance their vitality and rejuvenate their physical body may find the practice of BDJ helpful, whereas survivors who are looking for spiritual comfort or growth may consider practicing mindfulness as an entry point toward mind-body unity. IMPLICATIONS FOR PRACTICE: Mindfulness and BDJ may be helpful for survivors of colorectal cancer to improve their holistic wellness. Oncology nurses can consider prescription of mindfulness and/or BDJ for patients recovering from colorectal cancer.

2.
Health Qual Life Outcomes ; 19(1): 51, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33568146

RESUMO

BACKGROUND: Mindfulness has emerged as an important correlate of well-being in various clinical populations. The present study evaluated the psychometric properties of the 20-item short form of the Five Facet Mindfulness Questionnaire (FFMQ-SF) in the Chinese context. METHODS: The study sample was 127 Chinese colorectal cancer patients who completed the FFMQ-SF and validated physical and mental health measures. Factorial validity of the FFMQ-SF was assessed using Bayesian structural equation modeling (BSEM) via informative priors on cross-loadings and residual covariances. Linear regression analysis examined its convergent validity with the health measures on imputed datasets. RESULTS: The five-factor BSEM model with approximate zero cross-loadings and one residual covariance provided an adequate model fit (PPP = 0.07, RMSEA = 0.06, CFI = 0.95). Satisfactory reliability (ω = 0.77-0.85) was found in four of the five facets (except nonjudging). Acting with awareness predicted lower levels of perceived stress, negative affect, anxiety, depression, and illness symptoms (ß = - 0.37 to - 0.42) and better quality of life (ß = 0.29-0.32). Observing, nonjudging, and nonreacting did not show any significant associations (p > .05) with health measures. Acting with awareness was not significantly correlated (r < 0.15) with the other four facets. CONCLUSION: The present findings provide partial support for the psychometric properties of the FFMQ-SF in colorectal cancer patients. The nonjudging facet showed questionable validity and reliability in the present sample. Further studies with larger sample sizes are needed to elucidate the viability of FFMQ-SF as a measure of mindfulness facets in cancer patients.


Assuntos
Neoplasias Colorretais/psicologia , Atenção Plena , Qualidade de Vida , Inquéritos e Questionários/normas , Adulto , Teorema de Bayes , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria/instrumentação , Reprodutibilidade dos Testes
3.
Commun Biol ; 3(1): 310, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546838

RESUMO

Subsets of breast tumors present major clinical challenges, including triple-negative, metastatic/recurrent disease and rare histologies. Here, we developed 37 patient-derived xenografts (PDX) from these difficult-to-treat cancers to interrogate their molecular composition and functional biology. Whole-genome and transcriptome sequencing and reverse-phase protein arrays revealed that PDXs conserve the molecular landscape of their corresponding patient tumors. Metastatic potential varied between PDXs, where low-penetrance lung micrometastases were most common, though a subset of models displayed high rates of dissemination in organotropic or diffuse patterns consistent with what was observed clinically. Chemosensitivity profiling was performed in vivo with standard-of-care agents, where multi-drug chemoresistance was retained upon xenotransplantation. Consolidating chemogenomic data identified actionable features in the majority of PDXs, and marked regressions were observed in a subset that was evaluated in vivo. Together, this clinically-annotated PDX library with comprehensive molecular and phenotypic profiling serves as a resource for preclinical studies on difficult-to-treat breast tumors.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Endogâmicos NOD , Mutação , Medicina de Precisão , Prognóstico , Estudo de Prova de Conceito , Análise Serial de Proteínas/métodos , Sequenciamento Completo do Genoma
4.
Cell ; 173(7): 1755-1769.e22, 2018 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-29754820

RESUMO

High-grade serous ovarian cancer (HGSC) exhibits extensive malignant clonal diversity with widespread but non-random patterns of disease dissemination. We investigated whether local immune microenvironment factors shape tumor progression properties at the interface of tumor-infiltrating lymphocytes (TILs) and cancer cells. Through multi-region study of 212 samples from 38 patients with whole-genome sequencing, immunohistochemistry, histologic image analysis, gene expression profiling, and T and B cell receptor sequencing, we identified three immunologic subtypes across samples and extensive within-patient diversity. Epithelial CD8+ TILs negatively associated with malignant diversity, reflecting immunological pruning of tumor clones inferred by neoantigen depletion, HLA I loss of heterozygosity, and spatial tracking between T cell and tumor clones. In addition, combinatorial prognostic effects of mutational processes and immune properties were observed, illuminating how specific genomic aberration types associate with immune response and impact survival. We conclude that within-patient spatial immune microenvironment variation shapes intraperitoneal malignant spread, provoking new evolutionary perspectives on HGSC clonal dispersion.


Assuntos
Linfócitos do Interstício Tumoral/imunologia , Neoplasias Ovarianas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Proteína BRCA2/genética , Proteína BRCA2/metabolismo , Antígenos CD8/metabolismo , Análise por Conglomerados , Feminino , Antígenos HLA/genética , Antígenos HLA/metabolismo , Humanos , Perda de Heterozigosidade , Linfócitos do Interstício Tumoral/citologia , Linfócitos do Interstício Tumoral/metabolismo , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias Ovarianas/classificação , Neoplasias Ovarianas/imunologia , Polimorfismo de Nucleotídeo Único , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Sequenciamento Completo do Genoma , Adulto Jovem
5.
Sci Rep ; 7(1): 13467, 2017 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-29044127

RESUMO

Characterization and quantification of tumour clonal populations over time via longitudinal sampling are essential components in understanding and predicting the response to therapeutic interventions. Computational methods for inferring tumour clonal composition from deep-targeted sequencing data are ubiquitous, however due to the lack of a ground truth biological data, evaluating their performance is difficult. In this work, we generate a benchmark data set that simulates tumour longitudinal growth and heterogeneity by in vitro mixing of cancer cell lines with known proportions. We apply four different algorithms to our ground truth data set and assess their performance in inferring clonal composition using different metrics. We also analyse the performance of these algorithms on breast tumour xenograft samples. We conclude that methods that can simultaneously analyse multiple samples while accounting for copy number alterations as a factor in allelic measurements exhibit the most accurate predictions. These results will inform future functional genomics oriented studies of model systems where time series measurements in the context of therapeutic interventions are becoming increasingly common. These studies will need computational models which accurately reflect the multi-factorial nature of allele measurement in cancer including, as we show here, segmental aneuploidies.


Assuntos
Simulação por Computador , Modelos Biológicos , Neoplasias/etiologia , Neoplasias/patologia , Algoritmos , Animais , Neoplasias da Mama/etiologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Biologia Computacional/métodos , Variações do Número de Cópias de DNA , Modelos Animais de Doenças , Feminino , Xenoenxertos , Humanos , Camundongos , Polimorfismo de Nucleotídeo Único , Reprodutibilidade dos Testes , Sequenciamento do Exoma
6.
BMC Complement Altern Med ; 17(1): 390, 2017 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-28789681

RESUMO

BACKGROUND: Colorectal cancer imposes threats to patients' well-being. Although most physical symptoms can be managed by medication, psychosocial stressors may complicate survival and hamper quality of life. Mindfulness and Qigong, two kinds of mind-body exercise rooted in Eastern health philosophy, has been found effective in symptoms management, improving mental health, and reducing stress. With these potential benefits, a randomized controlled trial (RCT) is planned to investigate the comparative effectiveness of mindfulness and Baduanjin intervention on the bio-psychosocial wellbeing of people with colorectal cancer. METHODS/ DESIGN: A 3-arm RCT with waitlist control design will be used in this study. One hundred eighty-nine participants will be randomized into (i) Mindfulness, (ii) Baduanjin, or (iii) waitlist control groups. Participants in both the Baduanjin and mindfulness groups will receive 8-weeks of specific intervention. All three groups will undergo four assessment phases: (i) at baseline, (ii) at 4-week, (iii) at 8-week (post-intervention), and 6-month post-intervention (maintenance). All participants will be assessed in terms of cancer-related symptoms and symptom distress, mental health status, quality of life, stress level based on physiological marker. DISCUSSION: Based on prior research studies, participants in both the mindfulness and Baduanjn intervention group are expected to have better symptoms management, lower stress level, better mental health, and higher level of quality of life than the control group. This study contributes to better understanding on the common and unique effectiveness of mindfulness and Baduanjin qigong, as such patients and qualified healthcare professionals can select or provide practices which will produce maximum benefits, satisfaction, adherence, and sustainability. TRIAL REGISTRATION: The trial has been registered in the Clinical Trials Centre of the University of Hong Kong ( HKCTR-2198 ) on 08 March 2017.


Assuntos
Neoplasias Colorretais/complicações , Exercício Físico , Meditação , Saúde Mental , Atenção Plena , Qigong , Estresse Psicológico/terapia , Adolescente , Adulto , Protocolos Clínicos , Neoplasias Colorretais/psicologia , Feminino , Humanos , Masculino , Qualidade de Vida , Projetos de Pesquisa , Estresse Psicológico/etiologia
7.
Nat Genet ; 49(6): 856-865, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28436987

RESUMO

We studied the whole-genome point mutation and structural variation patterns of 133 tumors (59 high-grade serous (HGSC), 35 clear cell (CCOC), 29 endometrioid (ENOC), and 10 adult granulosa cell (GCT)) as a substrate for class discovery in ovarian cancer. Ab initio clustering of integrated point mutation and structural variation signatures identified seven subgroups both between and within histotypes. Prevalence of foldback inversions identified a prognostically significant HGSC group associated with inferior survival. This finding was recapitulated in two independent cohorts (n = 576 cases), transcending BRCA1 and BRCA2 mutation and gene expression features of HGSC. CCOC cancers grouped according to APOBEC deamination (26%) and age-related mutational signatures (40%). ENOCs were divided by cases with microsatellite instability (28%), with a distinct mismatch-repair mutation signature. Taken together, our work establishes the potency of the somatic genome, reflective of diverse DNA repair deficiencies, to stratify ovarian cancers into distinct biological strata within the major histotypes.


Assuntos
Reparo do DNA/genética , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Proteína BRCA1/genética , Proteína BRCA2/genética , Endometriose/complicações , Endometriose/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Humanos , Mutação , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/mortalidade , Prognóstico
8.
Sci Signal ; 9(436): ra69, 2016 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-27405979

RESUMO

The dynamic assembly of multiprotein complexes is a central mechanism of many cell signaling pathways. This process is key to maintaining the spatiotemporal specificity required for an accurate, yet adaptive, response to rapidly changing cellular conditions. We describe a technique for the specific isolation and downstream proteomic characterization of any two interacting proteins, to the exclusion of their individual moieties and competing binding partners. We termed the approach bimolecular complementation affinity purification (BiCAP) because it combines the use of conformation-specific nanobodies with a protein-fragment complementation assay with affinity purification. Using BiCAP, we characterized the specific interactome of the epidermal growth factor receptor (EGFR) family member ERBB2 when in the form of a homodimer or when in the form of a heterodimer with either EGFR or ERBB3. We identified dimer-specific interaction patterns for key adaptor proteins and identified a number of previously unknown interacting partners. Functional analysis for one of these newly identified partners revealed a noncanonical mechanism of extracellular signal-regulated kinase (ERK) activation that is specific to the ERBB2:ERBB3 heterodimer and acts through the adaptor protein FAM59A in breast cancer cells.


Assuntos
Neoplasias da Mama/metabolismo , Receptores ErbB , Sistema de Sinalização das MAP Quinases , Multimerização Proteica , Receptor ErbB-2 , Receptor ErbB-3 , Neoplasias da Mama/patologia , Receptores ErbB/isolamento & purificação , Receptores ErbB/metabolismo , Feminino , Células HEK293 , Humanos , Células MCF-7 , Receptor ErbB-2/isolamento & purificação , Receptor ErbB-2/metabolismo , Receptor ErbB-3/isolamento & purificação , Receptor ErbB-3/metabolismo
9.
Nat Methods ; 13(7): 573-6, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27183439

RESUMO

Single-cell DNA sequencing has great potential to reveal the clonal genotypes and population structure of human cancers. However, single-cell data suffer from missing values and biased allelic counts as well as false genotype measurements owing to the sequencing of multiple cells. We describe the Single Cell Genotyper (https://bitbucket.org/aroth85/scg), an open-source software based on a statistical model coupled with a mean-field variational inference method, which can be used to address these problems and robustly infer clonal genotypes.


Assuntos
Cistadenocarcinoma Seroso/genética , Leucemia/genética , Glândulas Mamárias Humanas/metabolismo , Neoplasias Ovarianas/genética , Análise de Célula Única/métodos , Software , Células Clonais , Feminino , Genoma Humano , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Modelos Estatísticos , Polimorfismo de Nucleotídeo Único/genética
10.
Nat Genet ; 48(7): 758-67, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27182968

RESUMO

We performed phylogenetic analysis of high-grade serous ovarian cancers (68 samples from seven patients), identifying constituent clones and quantifying their relative abundances at multiple intraperitoneal sites. Through whole-genome and single-nucleus sequencing, we identified evolutionary features including mutation loss, convergence of the structural genome and temporal activation of mutational processes that patterned clonal progression. We then determined the precise clonal mixtures comprising each tumor sample. The majority of sites were clonally pure or composed of clones from a single phylogenetic clade. However, each patient contained at least one site composed of polyphyletic clones. Five patients exhibited monoclonal and unidirectional seeding from the ovary to intraperitoneal sites, and two patients demonstrated polyclonal spread and reseeding. Our findings indicate that at least two distinct modes of intraperitoneal spread operate in clonal dissemination and highlight the distribution of migratory potential over clonal populations comprising high-grade serous ovarian cancers.


Assuntos
Biomarcadores Tumorais/genética , Células Clonais/patologia , Cistadenocarcinoma Seroso/patologia , Variação Genética/genética , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/patologia , Microambiente Tumoral/genética , Idoso , Células Clonais/metabolismo , Cistadenocarcinoma Seroso/genética , Progressão da Doença , Neoplasias das Tubas Uterinas/genética , Neoplasias das Tubas Uterinas/patologia , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Pessoa de Meia-Idade , Mutação/genética , Gradação de Tumores , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Neoplasias Ovarianas/genética , Neoplasias Peritoneais/genética , Filogenia , Análise de Célula Única/métodos , Taxa de Sobrevida
11.
Breast Cancer Res ; 17: 4, 2015 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-25572802

RESUMO

INTRODUCTION: The extracellular signals regulating mammary epithelial cell growth are of relevance to understanding the pathophysiology of mammary epithelia, yet they remain poorly characterized. In this study, we applied an unbiased approach to understanding the functional role of signalling molecules in several models of normal physiological growth and translated these results to the biological understanding of breast cancer subtypes. METHODS: We developed and utilized a cytogenetically normal clonal line of hTERT immortalized human mammary epithelial cells in a fibroblast-enhanced co-culture assay to conduct a genome-wide small interfering RNA (siRNA) screen for evaluation of the functional effect of silencing each gene. Our selected endpoint was inhibition of growth. In rigorous postscreen validation processes, including quantitative RT-PCR, to ensure on-target silencing, deconvolution of pooled siRNAs and independent confirmation of effects with lentiviral short-hairpin RNA constructs, we identified a subset of genes required for mammary epithelial cell growth. Using three-dimensional Matrigel growth and differentiation assays and primary human mammary epithelial cell colony assays, we confirmed that these growth effects were not limited to the 184-hTERT cell line. We utilized the METABRIC dataset of 1,998 breast cancer patients to evaluate both the differential expression of these genes across breast cancer subtypes and their prognostic significance. RESULTS: We identified 47 genes that are critically important for fibroblast-enhanced mammary epithelial cell growth. This group was enriched for several axonal guidance molecules and G protein-coupled receptors, as well as for the endothelin receptor PROCR. The majority of genes (43 of 47) identified in two dimensions were also required for three-dimensional growth, with HSD17B2, SNN and PROCR showing greater than tenfold reductions in acinar formation. Several genes, including PROCR and the neuronal pathfinding molecules EFNA4 and NTN1, were also required for proper differentiation and polarization in three-dimensional cultures. The 47 genes identified showed a significant nonrandom enrichment for differential expression among 10 molecular subtypes of breast cancer sampled from 1,998 patients. CD79A, SERPINH1, KCNJ5 and TMEM14C exhibited breast cancer subtype-independent overall survival differences. CONCLUSION: Diverse transmembrane signals are required for mammary epithelial cell growth in two-dimensional and three-dimensional conditions. Strikingly, we define novel roles for axonal pathfinding receptors and ligands and the endothelin receptor in both growth and differentiation.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Membrana Celular/metabolismo , Células Epiteliais/metabolismo , Interferência de RNA , Transdução de Sinais , Adulto , Animais , Neoplasias da Mama/patologia , Comunicação Celular , Diferenciação Celular , Linhagem Celular Transformada , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Análise por Conglomerados , Técnicas de Cocultura , Feminino , Fibroblastos/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Estudo de Associação Genômica Ampla/métodos , Ensaios de Triagem em Larga Escala , Humanos , Cariótipo , Camundongos , RNA Interferente Pequeno/genética , Esferoides Celulares , Telomerase/genética , Células Tumorais Cultivadas , Adulto Jovem
12.
Nature ; 518(7539): 422-6, 2015 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-25470049

RESUMO

Human cancers, including breast cancers, comprise clones differing in mutation content. Clones evolve dynamically in space and time following principles of Darwinian evolution, underpinning important emergent features such as drug resistance and metastasis. Human breast cancer xenoengraftment is used as a means of capturing and studying tumour biology, and breast tumour xenografts are generally assumed to be reasonable models of the originating tumours. However, the consequences and reproducibility of engraftment and propagation on the genomic clonal architecture of tumours have not been systematically examined at single-cell resolution. Here we show, using deep-genome and single-cell sequencing methods, the clonal dynamics of initial engraftment and subsequent serial propagation of primary and metastatic human breast cancers in immunodeficient mice. In all 15 cases examined, clonal selection on engraftment was observed in both primary and metastatic breast tumours, varying in degree from extreme selective engraftment of minor (<5% of starting population) clones to moderate, polyclonal engraftment. Furthermore, ongoing clonal dynamics during serial passaging is a feature of tumours experiencing modest initial selection. Through single-cell sequencing, we show that major mutation clusters estimated from tumour population sequencing relate predictably to the most abundant clonal genotypes, even in clonally complex and rapidly evolving cases. Finally, we show that similar clonal expansion patterns can emerge in independent grafts of the same starting tumour population, indicating that genomic aberrations can be reproducible determinants of evolutionary trajectories. Our results show that measurement of genomically defined clonal population dynamics will be highly informative for functional studies using patient-derived breast cancer xenoengraftment.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Células Clonais/metabolismo , Células Clonais/patologia , Genoma Humano/genética , Análise de Célula Única , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Neoplasias da Mama/secundário , Análise Mutacional de DNA , Genômica , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Camundongos , Transplante de Neoplasias , Fatores de Tempo , Transplante Heterólogo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
13.
Nat Methods ; 11(4): 396-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24633410

RESUMO

We introduce PyClone, a statistical model for inference of clonal population structures in cancers. PyClone is a Bayesian clustering method for grouping sets of deeply sequenced somatic mutations into putative clonal clusters while estimating their cellular prevalences and accounting for allelic imbalances introduced by segmental copy-number changes and normal-cell contamination. Single-cell sequencing validation demonstrates PyClone's accuracy.


Assuntos
Teorema de Bayes , Análise por Conglomerados , Modelos Biológicos , Modelos Estatísticos , Neoplasias/metabolismo , Algoritmos , Alelos , Animais , Análise Mutacional de DNA/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Mutação , Reprodutibilidade dos Testes , Software
14.
N Engl J Med ; 366(3): 234-42, 2012 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-22187960

RESUMO

BACKGROUND: Germline truncating mutations in DICER1, an endoribonuclease in the RNase III family that is essential for processing microRNAs, have been observed in families with the pleuropulmonary blastoma-family tumor and dysplasia syndrome. Mutation carriers are at risk for nonepithelial ovarian tumors, notably sex cord-stromal tumors. METHODS: We sequenced the whole transcriptomes or exomes of 14 nonepithelial ovarian tumors and noted closely clustered mutations in the region of DICER1 encoding the RNase IIIb domain of DICER1 in four samples. We then sequenced this region of DICER1 in additional ovarian tumors and in certain other tumors and queried the effect of the mutations on the enzymatic activity of DICER1 using in vitro RNA cleavage assays. RESULTS: DICER1 mutations in the RNase IIIb domain were found in 30 of 102 nonepithelial ovarian tumors (29%), predominantly in Sertoli-Leydig cell tumors (26 of 43, or 60%), including 4 tumors with additional germline DICER1 mutations. These mutations were restricted to codons encoding metal-binding sites within the RNase IIIb catalytic centers, which are critical for microRNA interaction and cleavage, and were somatic in all 16 samples in which germline DNA was available for testing. We also detected mutations in 1 of 14 nonseminomatous testicular germ-cell tumors, in 2 of 5 embryonal rhabdomyosarcomas, and in 1 of 266 epithelial ovarian and endometrial carcinomas. The mutant DICER1 proteins had reduced RNase IIIb activity but retained RNase IIIa activity. CONCLUSIONS: Somatic missense mutations affecting the RNase IIIb domain of DICER1 are common in nonepithelial ovarian tumors. These mutations do not obliterate DICER1 function but alter it in specific cell types, a novel mechanism through which perturbation of microRNA processing may be oncogenic. (Funded by the Terry Fox Research Institute and others.).


Assuntos
RNA Helicases DEAD-box/genética , Mutação de Sentido Incorreto , Neoplasias Ovarianas/genética , Ribonuclease III/genética , Tumor de Células de Sertoli-Leydig/genética , Carcinossarcoma/genética , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Mutação em Linhagem Germinativa , Humanos , MicroRNAs/metabolismo , Neoplasias Embrionárias de Células Germinativas/genética , Rabdomiossarcoma/genética , Análise de Sequência de DNA
15.
Blood ; 118(16): 4366-76, 2011 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-21865344

RESUMO

Achieving high-level expansion of hematopoietic stem cells (HSCs) in vitro will have an important clinical impact in addition to enabling elucidation of their regulation. Here, we couple the ability of engineered NUP98-HOXA10hd expression to stimulate > 1000-fold net expansions of murine HSCs in 10-day cultures initiated with bulk lin(-)Sca-1(+)c-kit(+) cells, with strategies to purify fetal and adult HSCs and analyze their expansion clonally. We find that NUP98-HOXA10hd stimulates comparable expansions of HSCs from both sources at ∼ 60% to 90% unit efficiency in cultures initiated with single cells. Clonally expanded HSCs consistently show balanced long-term contributions to the lymphoid and myeloid lineages without evidence of leukemogenic activity. Although effects on fetal and adult HSCs were indistinguishable, NUP98-HOXA10hd-transduced adult HSCs did not thereby gain a competitive advantage in vivo over freshly isolated fetal HSCs. Live-cell image tracking of single transduced HSCs cultured in a microfluidic device indicates that NUP98-HOXA10hd does not affect their proliferation kinetics, and flow cytometry confirmed the phenotype of normal proliferating HSCs and allowed reisolation of large numbers of expanded HSCs at a purity of 25%. These findings point to the effects of NUP98-HOXA10hd on HSCs in vitro being mediated by promoting self-renewal and set the stage for further dissection of this process.


Assuntos
Técnicas de Cultura de Células/métodos , Células-Tronco Hematopoéticas/citologia , Proteínas de Homeodomínio/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas Recombinantes de Fusão/genética , Fatores de Transcrição/genética , Animais , Proliferação de Células , Separação Celular , Células Cultivadas , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Engenharia de Proteínas , Transdução Genética
16.
Leuk Res ; 35(4): 545-50, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21130494

RESUMO

To determine the contribution of the common N-terminal truncation of NUP98 in NUP98-translocations resulting in acute myeloid leukemia, we have conducted a structure-function analysis of NUP98 in the context of NUP98-HOXA10HD, a novel, canonical NUP98-Hox fusion that significantly enhances the self-renewal capacity of hematopoietic stem cells and collaborates with Meis1 to induce AML in our mouse models. Our results identify that NUP98 functions by transcriptional activation likely by recruitment of CBP/p300 via its FG/GLFG repeats. In contrast, the functional interaction of NUP98 with Rae1 or the anaphase promoting complex appears non-essential for its role in NUP98-leukemogenic fusions.


Assuntos
Proteínas de Homeodomínio/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Doença Aguda , Sequência de Aminoácidos , Animais , Sítios de Ligação , Células da Medula Óssea/metabolismo , Transformação Celular Neoplásica/genética , Células Cultivadas , Feminino , Proteínas Homeobox A10 , Proteínas de Homeodomínio/genética , Estimativa de Kaplan-Meier , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patologia , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Proteína Meis1 , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Associadas à Matriz Nuclear/genética , Proteínas Associadas à Matriz Nuclear/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas de Transporte Nucleocitoplasmático/genética , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Proteínas de Fusão Oncogênica/genética , Ligação Proteica , Sequências Repetitivas de Aminoácidos , Fatores de Transcrição de p300-CBP/genética , Fatores de Transcrição de p300-CBP/metabolismo
17.
Exp Hematol ; 36(7): 845-59, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18375036

RESUMO

OBJECTIVE: MEIS1, a HOX cofactor, collaborates with multiple HOX and NUP98-HOX fusion proteins to accelerate the onset of acute myeloid leukemia (AML) through largely unknown molecular mechanisms. MATERIALS AND METHODS: To further resolve these mechanisms, we conducted a structure-function analysis of MEIS1 and gene-expression profiling, in the context of NUP98-HOXD13 (ND13) leukemogenesis. RESULTS: We show, in a murine bone marrow transplantation model, that the PBX-interaction domain, the homeodomain, and the C-terminal domain of MEIS1, are all required for leukemogenic collaboration with ND13. In contrast, the N-terminal domain of MEIS1 is dispensable for collaboration with ND13, but is required for Flt3 upregulation, indicating additional roles for MEIS1 in induction of leukemia independent of alterations in Flt3 expression. Gene-expression profiling of a cloned ND13 preleukemic cell line transduced with wild-type or Meis1 mutant forms revealed deregulation of multiple genes, including a set not previously implicated as MEIS1 targets. Chromatin immunoprecipitation revealed the in vivo occupancy of MEIS1 on regulatory sequences of Trib2, Flt3, Dlk1, Ccl3, Ccl4, Pf4, and Rgs1. Furthermore, engineered overexpression of Trib2 complements ND13 to induce AML while Ccl3 potentiates the repopulating ability of ND13. CONCLUSION: This study shows that Meis1-induced leukemogenesis with ND13 can occur in the absence of Flt3 upregulation and reveals the existence of other pathways activated by MEIS1 to promote leukemia.


Assuntos
Transformação Celular Neoplásica/metabolismo , Quimiocina CCL3/biossíntese , Ligação Genética , Proteínas de Homeodomínio/biossíntese , Leucemia Mieloide Aguda/metabolismo , Proteínas de Neoplasias/biossíntese , Proteínas Serina-Treonina Quinases/biossíntese , Animais , Transplante de Medula Óssea , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Quimiocina CCL3/genética , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Regulação Leucêmica da Expressão Gênica/genética , Teste de Complementação Genética , Proteínas de Homeodomínio/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Leucemia Mieloide Aguda/genética , Camundongos , Proteína Meis1 , Proteínas de Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Proteínas Serina-Treonina Quinases/genética , Estrutura Terciária de Proteína/genética , Elementos de Resposta/genética , Retroviridae , Relação Estrutura-Atividade , Transdução Genética
18.
Blood ; 108(3): 1030-6, 2006 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16861351

RESUMO

In leukemogenesis, several genetic changes conferring a proliferative and/or survival advantage to hematopoietic progenitor cells in addition to a block in differentiation are required. Here, we demonstrate that overexpression of the wild-type (wt) Flt3 receptor tyrosine kinase collaborates with NUP98-HOX fusions (NUP98-HOXA10 and NUP98-HOXD13) to induce aggressive acute myeloid leukemia (AML). We used a mouse transplantation model to show their synergism in cotransduced bone marrow cells as well as in a cellular model of leukemic progression. Furthermore, our data support the finding that Meis1 overexpression leads to marked elevation in Flt3 transcription and extend it to the context of NUP98-HOX-induced leukemia. Together, these results support a multistep model where the synergism between NUP98-HOX and wt-Flt3 is the result of the ability of Flt3 to increase proliferation of myeloid progenitors blocked in differentiation by NUP98-HOX fusions and reveal a direct role for wt-Flt3 in the pathobiology of AML. Given the similarities in the leukemogenic role of native HOX and NUP98-fused HOX genes, our results underscore the clinical significance of the recurrent co-overexpression of wt-FLT3 and HOX in human leukemia and suggest that specific FLT3 inhibitors could be useful in treatment of HOX-induced AML or acute lymphoblastic leukemia (ALL).


Assuntos
Proteínas de Homeodomínio/genética , Leucemia Mieloide/etiologia , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas de Fusão Oncogênica , Doença Aguda , Animais , Células da Medula Óssea , Transplante de Medula Óssea , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Proteínas Homeobox A10 , Leucemia Mieloide/genética , Camundongos , Fatores de Transcrição , Tirosina Quinase 3 Semelhante a fms/genética
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