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2.
Contemp Clin Trials ; 107: 106480, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34126263

RESUMO

BACKGROUND: Exposure to ultraviolet radiation (UVR) is the major modifiable risk factor for skin cancers. The majority of lifetime UVR exposure occurs before age 20, underscoring an important window for risk reduction. Incorporation of skills-based sunscreen education into school health curricula may foster the development of consistent and effective use of sunscreen among children and youth. We describe the study protocol for a first-of-its-kind study that examined the feasibility of bringing skills-based sunscreen education into kindergarten classrooms. METHODS: Participants were 96 kindergarten students across four classrooms in a single elementary school. A single-blind open-label trial design was used to evaluate the feasibility of incorporating a song-based, video-guided intervention for independent application of sunscreen into the kindergarten curriculum. Students first completed a 10-day no-intervention baseline period, followed by a 10-day intervention period, and then a 10-day randomized follow-up period where students were randomly assigned to continue with the intervention or to revert to the no-intervention condition. OUTCOMES: Feasibility metrics associated with study process, resources, management, scientific outcomes and safety were gathered. The primary outcome was pre-to-post intervention changes in student engagement in the sunscreen task. The secondary outcome was pre-to-post intervention changes in the proportion of exposed skin to which a student applies sunscreen. Teacher and student perceptions of intervention value and utility were also evaluated. DISCUSSION: This is the study protocol for a clinical trial designed to determine the feasibility of implementing a skills-based sunscreen curriculum in kindergarten classrooms. Next steps include evaluation of the intervention for efficacy and effectiveness. CLINICAL TRIAL REGISTRATION: NCT03752736.


Assuntos
Protetores Solares , Raios Ultravioleta , Pré-Escolar , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Instituições Acadêmicas , Método Simples-Cego , Estudantes , Raios Ultravioleta/efeitos adversos
4.
J Am Acad Dermatol ; 79(1): 36-41.e10, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29499294

RESUMO

BACKGROUND: Single-nucleotide polymorphisms (SNPs) associated with melanoma have been identified though genome-wide association studies. However, the combined impact of these SNPs on melanoma development remains unclear, particularly in postmenopausal women who carry a lower melanoma risk. OBJECTIVE: We examine the contribution of a combined polygenic risk score on melanoma development in postmenopausal women. METHODS: Genetic risk scores were calculated using 21 genome-wide association study-significant SNPs. Their combined effect on melanoma development was evaluated in 19,102 postmenopausal white women in the clinical trial and observational study arms of the Women's Health Initiative dataset. RESULTS: Compared to the tertile of weighted genetic risk score with the lowest genetic risk, the women in the tertile with the highest genetic risk were 1.9 times more likely to develop melanoma (95% confidence interval 1.50-2.42). The incremental change in c-index from adding genetic risk scores to age were 0.075 (95% confidence interval 0.041-0.109) for incident melanoma. LIMITATIONS: Limitations include a lack of information on nevi count, Fitzpatrick skin type, family history of melanoma, and potential reporting and selection bias in the Women's Health Initiative cohort. CONCLUSION: Higher genetic risk is associated with increased melanoma prevalence and incidence in postmenopausal women, but current genetic information may have a limited role in risk prediction when phenotypic information is available.


Assuntos
Predisposição Genética para Doença/epidemiologia , Estudo de Associação Genômica Ampla , Melanoma/epidemiologia , Melanoma/genética , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/genética , Distribuição por Idade , Idoso , Estudos de Coortes , Bases de Dados Factuais , Feminino , Humanos , Modelos Logísticos , Melanoma/patologia , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Pós-Menopausa , Valor Preditivo dos Testes , Prevalência , Prognóstico , Modelos de Riscos Proporcionais , Medição de Risco , Neoplasias Cutâneas/patologia , Estados Unidos/epidemiologia , Saúde da Mulher
5.
Int J Cancer ; 141(5): 952-957, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28510302

RESUMO

DNA repair plays a critical role in protecting the genome from ultraviolet radiation and maintaining the genomic integrity of cells. Genetic variants in DNA repair-related genes can influence an individual's DNA repair capacity, which may be related to the risk of developing basal cell carcinoma (BCC). We comprehensively assessed the associations of 2,965 independent single-nucleotide polymorphisms (SNPs) across 165 DNA repair pathway genes with BCC risk in a genome-wide association meta-analysis totaling 17,187 BCC cases and 287,054 controls from two data sets. After multiple testing corrections, we identified three SNPs (rs2805831 upstream of XPA: OR = 0.93, P = 1.35 × 10-6 ; rs659857 in exon of MUS81: OR = 1.06, P = 3.09 × 10-6 and rs57343616 in 3' UTR of NABP2: OR = 1.11, P = 6.47 × 10-6 ) as significantly associated with BCC risk in meta-analysis, and all of them were nominally significant in both data sets. Furthermore, rs659857 [T] was significantly associated with decreased expression of MUS81 mRNA in the expression quantitative trait locus (eQTL) analysis. Our findings suggest that the inherited common variation in three DNA repair genes-XPA, MUS81 and NABP2-may be involved in the development of BCC. To our knowledge, our study is the first report thoroughly examining the effects of SNPs across DNA repair pathway genes on BCC risk based on a genome-wide association meta-analysis.


Assuntos
Carcinoma Basocelular/genética , Reparo do DNA/genética , Predisposição Genética para Doença/genética , Neoplasias Cutâneas/genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único
6.
Oncotarget ; 8(11): 17586-17592, 2017 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-28212542

RESUMO

Genome-wide association studies have identified 21 susceptibility loci associated with melanoma. These loci implicate genes affecting pigmentation, nevus count, telomere maintenance, and DNA repair in melanoma risk. Here, we report the results of a two-stage genome-wide association study of melanoma. The stage 1 discovery phase consisted of 4,842 self-reported melanoma cases and 286,565 controls of European ancestry from the 23andMe research cohort and the stage 2 replication phase consisted of 1,804 melanoma cases and 1,026 controls from the University of Texas M.D. Anderson Cancer Center. We performed a combined meta-analysis totaling 6,628 melanoma cases and 287,591 controls. Our study replicates 20 of 21 previously known melanoma-loci and confirms the association of the telomerase reverse transcriptase, TERT, with melanoma susceptibility at genome-wide significance. In addition, we uncover a novel polymorphism, rs187843643 (OR = 1.96; 95% CI = [1.54, 2.48]; P = 3.53 x 10-8), associated with melanoma. The SNP rs187842643 lies within a noncoding RNA 177kb downstream of BASP1 (brain associated protein-1). We find that BASP1 expression is suppressed in melanoma as compared with benign nevi, providing additional evidence for a putative role in melanoma pathogenesis.


Assuntos
Regulação Neoplásica da Expressão Gênica/genética , Predisposição Genética para Doença/genética , Melanoma/genética , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Proteínas Repressoras/genética , Neoplasias Cutâneas/genética , Adulto , Idoso , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Telomerase/genética
7.
Int J Cancer ; 140(9): 2085-2091, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28177523

RESUMO

An increasing number of studies have reported a protective association between vitamin D and cancer risk. The vitamin D endocrine system regulates transcriptional programs involved in inflammation, cell growth and differentiation through the binding of vitamin D receptor (VDR) to specific VDR elements. However, limited attention has been given to the role of variation within VDR binding sites in the development of basal cell carcinoma (BCC). Across 2,776 previously identified VDR binding sites, we identified 2,540 independent single-nucleotide polymorphisms (SNPs) and examined their associations with BCC risk in a genome-wide association meta-analysis totaling 17,187 BCC cases and 287,054 controls from two data sets. After multiple testing corrections, we identified two SNPs at new loci (rs16917546 at 10q21.1: odds ratio (OR) = 1.06, p = 3.16 × 10-7 and rs79824801 at 12q13.3: OR = 1.10, p = 1.88 × 10-5 ) for the first time as independently related to BCC risk in meta-analysis; and both SNPs were nominally significant in two data sets. In addition, the SNP rs3769823 within VDR binding site at a previously reported BCC susceptibility locus (2q33.1, rs13014235) also exhibited a significant association (OR = 1.12, p = 3.99 × 10-18 ). A mutually adjusted model suggested that rs3769823 explained the signal in this region. Our findings support the hypothesis that inherited common variation in VDR binding sites affects the development of BCC.


Assuntos
Carcinoma Basocelular/genética , Estudo de Associação Genômica Ampla , Receptores de Calcitriol/genética , Neoplasias Cutâneas/genética , Adulto , Idoso , Sítios de Ligação/genética , Carcinoma Basocelular/epidemiologia , Carcinoma Basocelular/patologia , Predisposição Genética para Doença , Genótipo , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Receptores de Calcitriol/metabolismo , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/patologia , Vitamina D/metabolismo
8.
JAMA Dermatol ; 153(2): 189-192, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27902821

RESUMO

IMPORTANCE: Patients with basal cell nevus syndrome (BCNS) have a greater risk of developing numerous basal cell carcinomas (BCCs). Risk factors influencing the wide variation in tumor burden are poorly understood. OBJECTIVE: To describe the burden of BCCs in patients with BCNS in the United States and identify potential risk factors for BCCs. DESIGN, SETTING, AND PARTICIPANTS: Prospective clinical registry with data collected from September 2014 to March 2016. Participants were recruited from a mailing list of patients with BCNS at Children's Hospital Oakland Research Institute and Basal Cell Carcinoma Nevus Syndrome Life Support Network. Patients of all ages with a diagnosis of BCNS were eligible for enrollment. Participants completed a clinical questionnaire on their disease characteristics and risk factors. MAIN OUTCOMES AND MEASURES: Number of BCCs in the past 2 years and over lifetime (disease burden), risk factors for BCCs. RESULTS: A consecutive sample of the first 141 participants was included (34% [100 of 297] response rate from paper survey, 23% [41 of 179] from online survey; 85 [60%] female; mean age at start of study, 53 [range, 8-83] years; 131 [93%] white). In the previous 2 years, participants reported a mean of 25 BCCs (median, 11; range, 0-250). Over their lifetime, participants reported a mean of 257 BCCs (median, 160; range, 0-2200). Univariate analysis identified age (odds ratio [OR], 1.05; 95% CI, 1.03-1.07; P < .001), number of sunburns (OR, 1.05; 95% CI, 1.00-1.10; P = .047), and history of radiation exposure (OR, 2.26; 95% CI, 1.02-5.03; P = .046) as potential risk factors for lifetime BCC severity. On multivariate analysis, only age (OR, 1.04; 95% CI, 1.02-1.07; P < .001) and number of sunburns (OR, 1.06; 95% CI, 1.00-1.11; P = .04) were statistically significant. In our adjusted models, BCC burden increased by 4% per year of age and by 6% per number of sunburns. CONCLUSIONS AND RELEVANCE: Patients with BCNS have a high burden of BCCs. Age and number of sunburns were significantly associated with the severity of lifetime BCC. Further interventions to prevent and treat BCCs in patients with BCNS are needed.

9.
Nat Commun ; 7: 12510, 2016 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-27539887

RESUMO

Basal cell carcinoma (BCC) is the most common cancer worldwide with an annual incidence of 2.8 million cases in the United States alone. Previous studies have demonstrated an association between 21 distinct genetic loci and BCC risk. Here, we report the results of a two-stage genome-wide association study of BCC, totalling 17,187 cases and 287,054 controls. We confirm 17 previously reported loci and identify 14 new susceptibility loci reaching genome-wide significance (P<5 × 10(-8), logistic regression). These newly associated SNPs lie within predicted keratinocyte regulatory elements and in expression quantitative trait loci; furthermore, we identify candidate genes and non-coding RNAs involved in telomere maintenance, immune regulation and tumour progression, providing deeper insight into the pathogenesis of BCC.


Assuntos
Carcinoma Basocelular/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Neoplasias Cutâneas/genética , Adulto , Alelos , Carcinoma Basocelular/imunologia , Carcinoma Basocelular/patologia , Estudos de Casos e Controles , Progressão da Doença , Feminino , Genótipo , Humanos , Queratinócitos/imunologia , Queratinócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Locos de Características Quantitativas , RNA não Traduzido/genética , Pele/citologia , Pele/patologia , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Homeostase do Telômero/genética
10.
Nat Commun ; 7: 12048, 2016 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-27424798

RESUMO

Cutaneous squamous cell carcinoma represents the second most common cutaneous malignancy, affecting 7-11% of Caucasians in the United States. The genetic determinants of susceptibility to cutaneous squamous cell carcinoma remain largely unknown. Here we report the results of a two-stage genome-wide association study of cutaneous squamous cell carcinoma, totalling 7,404 cases and 292,076 controls. Eleven loci reached genome-wide significance (P<5 × 10(-8)) including seven previously confirmed pigmentation-related loci: MC1R, ASIP, TYR, SLC45A2, OCA2, IRF4 and BNC2. We identify an additional four susceptibility loci: 11q23.3 CADM1, a metastasis suppressor gene involved in modifying tumour interaction with cell-mediated immunity; 2p22.3; 7p21.1 AHR, the dioxin receptor involved in anti-apoptotic pathways and melanoma progression; and 9q34.3 SEC16A, a putative oncogene with roles in secretion and cellular proliferation. These susceptibility loci provide deeper insight into the pathogenesis of squamous cell carcinoma.


Assuntos
Carcinoma de Células Escamosas/genética , Loci Gênicos , Predisposição Genética para Doença , Genoma Humano , Proteínas de Neoplasias/genética , Neoplasias Cutâneas/genética , Adulto , Idoso , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , Mapeamento Cromossômico , Feminino , Estudo de Associação Genômica Ampla , Humanos , Padrões de Herança , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
11.
Cancer Causes Control ; 27(6): 817-23, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27153844

RESUMO

BACKGROUND: Sun exposure is a major risk factor for skin cancer; however, the relative contribution of ultraviolet (UV) exposure during childhood versus adulthood on skin cancer risk remains unclear. OBJECTIVE: Our goal was to determine the impact of residential UV, measured by AVerage daily total GLObal solar radiation (AVGLO), exposure during childhood (birth, 15 years) versus adulthood (35, 50 years, and present) on incident non-melanoma skin cancer (NMSC) and malignant melanoma (MM) in postmenopausal women. METHODS: Women were followed with yearly surveys throughout the duration of their participation in the Women's Health Initiative Observational study, a multicenter study from 1993 to 2005. A total of 56,557 women had data on all observations and were included in the baseline characteristics. The main exposure, residential UV (as measured by AVGLO), was measured by geographic residence during childhood and adulthood. Outcome was risk of incident NMSC and MM. RESULTS: Over 11.9 years (median follow-up), there were 9,195 (16.3 %) cases of NMSC and 518 (0.92 %) cases of MM. Compared with the reference group (women with low childhood and low adulthood UV), women with low childhood and high adulthood UV had a 21 % increased risk of NMSC (odds ratio 1.21, 95 % confidence interval 1.12, 1.31). Women with high childhood and high adulthood UV had a 19 % increased risk of NMSC (odds ratio 1.19, 95 % confidence interval 1.11, 1.27). Surprisingly, women with high childhood UV and low adulthood UV did not have a significant increase in NMSC risk compared with the reference group (odds ratio 1.08, 95 % confidence interval 0.91, 1.28) in multivariable models. Residential UV exposure in childhood or adulthood was not associated with increased melanoma risk. CONCLUSION: This study reveals an increase in NMSC risk associated with adulthood residential UV exposure, with no effect for childhood UV exposure.


Assuntos
Carcinoma Basocelular/epidemiologia , Carcinoma de Células Escamosas/epidemiologia , Exposição Ambiental/estatística & dados numéricos , Melanoma/epidemiologia , Neoplasias Cutâneas/epidemiologia , Raios Ultravioleta , População Branca , Fatores Etários , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Razão de Chances , Pós-Menopausa , Fatores de Risco , Saúde da Mulher
12.
J Am Acad Dermatol ; 74(3): 423-34; quiz 435-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26892652

RESUMO

Phenotypic traits, such as red hair and freckling, increase melanoma risk by 2- to 3-fold. In addition, approximately 10% of melanomas are caused by inherited germline mutations that increase melanoma risk from 4- to >1000-fold. This review highlights the key genes responsible for inherited melanoma, with an emphasis on when a patient should undergo genetic testing. Many genetic syndromes associated with increased melanoma risk are also associated with an increased risk of other cancers. Identification of these high-risk patients is essential for preventive behavior reinforcement, genetic counseling, and ensuring other required cancer screenings.


Assuntos
Melanoma/epidemiologia , Melanoma/genética , Síndromes Neoplásicas Hereditárias , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/genética , Humanos , Melanoma/diagnóstico , Melanoma/terapia , Síndromes Neoplásicas Hereditárias/diagnóstico , Síndromes Neoplásicas Hereditárias/epidemiologia , Síndromes Neoplásicas Hereditárias/terapia , Risco , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/terapia
13.
J Am Acad Dermatol ; 74(3): 437-51; quiz 452-4, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26892653

RESUMO

Nonmelanoma skin cancers (NMSCs) represent the most common malignancies worldwide, with reported incidence rising each year. Both cutaneous squamous cell carcinoma (SCC) and basal cell carcinoma (BCC), as well as other NMSCs, represent complex diseases with a combination of environmental and genetic risk factors. In general, hereditary cancer syndromes that increase the risk of NMSC fall under several broad categories: those associated with immunodeficiencies, those that affect skin pigmentation, and those that perturb key molecular pathways involved in the pathogenesis of NMSCs. Many of the syndromes are also associated with extracutaneous manifestations, including internal malignancies; therefore, most require a multidisciplinary management approach with a medical geneticist. Finally, dermatologists play a critical role in the diagnosis and management of these conditions, because cutaneous findings are often the presenting manifestations of disease.


Assuntos
Síndromes Neoplásicas Hereditárias/epidemiologia , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/genética , Carcinoma Basocelular/diagnóstico , Carcinoma Basocelular/epidemiologia , Carcinoma Basocelular/terapia , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/terapia , Árvores de Decisões , Humanos , Síndromes Neoplásicas Hereditárias/diagnóstico , Síndromes Neoplásicas Hereditárias/terapia , Risco , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/terapia
16.
Stem Cells ; 31(11): 2354-63, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24038578

RESUMO

RATIONALE: Human embryonic stem cell (hESC) derivatives are attractive candidates for therapeutic use. The engraftment and survival of hESC derivatives as xenografts or allografts require effective immunosuppression to prevent immune cell infiltration and graft destruction. OBJECTIVE: To test the hypothesis that a short-course, dual-agent regimen of two costimulation-adhesion blockade agents can induce better engraftment of hESC derivatives compared to current immunosuppressive agents. METHODS AND RESULTS: We transduced hESCs with a double fusion reporter gene construct expressing firefly luciferase (Fluc) and enhanced green fluorescent protein, and differentiated these cells to endothelial cells (hESC-ECs). Reporter gene expression enabled longitudinal assessment of cell engraftment by bioluminescence imaging. Costimulation-adhesion therapy resulted in superior hESC-EC and mouse EC engraftment compared to cyclosporine therapy in a hind limb model. Costimulation-adhesion therapy also promoted robust hESC-EC and hESC-derived cardiomyocyte survival in an ischemic myocardial injury model. Improved hESC-EC engraftment had a cardioprotective effect after myocardial injury, as assessed by magnetic resonance imaging. Mechanistically, costimulation-adhesion therapy is associated with systemic and intragraft upregulation of T-cell immunoglobulin and mucin domain 3 (TIM3) and a reduced proinflammatory cytokine profile. CONCLUSIONS: Costimulation-adhesion therapy is a superior alternative to current clinical immunosuppressive strategies for preventing the post-transplant rejection of hESC derivatives. By extending the window for cellular engraftment, costimulation-adhesion therapy enhances functional preservation following ischemic injury. This regimen may function through a TIM3-dependent mechanism.


Assuntos
Anticorpos Monoclonais/farmacologia , Ciclosporina/farmacologia , Células-Tronco Embrionárias/transplante , Rejeição de Enxerto/prevenção & controle , Imunoconjugados/farmacologia , Imunossupressores/farmacologia , Prednisona/farmacologia , Abatacepte , Animais , Cardiotônicos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/imunologia , Células Endoteliais/imunologia , Células Endoteliais/transplante , Rejeição de Enxerto/imunologia , Humanos , Tolerância Imunológica , Terapia de Imunossupressão/métodos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/cirurgia , Distribuição Aleatória
17.
Stem Cells ; 31(2): 259-68, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23136034

RESUMO

MicroRNAs (miRNAs) have emerged as critical regulators of gene expression through translational inhibition and RNA decay and have been implicated in the regulation of cellular differentiation, proliferation, angiogenesis, and apoptosis. In this study, we analyzed global miRNA and mRNA microarrays to predict novel miRNA-mRNA interactions in human embryonic stem cells and induced pluripotent stem cells (iPSCs). In particular, we demonstrate a regulatory feedback loop between the miR-302 cluster and two transcription factors, NR2F2 and OCT4. Our data show high expression of miR-302 and OCT4 in pluripotent cells, while NR2F2 is expressed exclusively in differentiated cells. Target analysis predicts that NR2F2 is a direct target of miR-302, which we experimentally confirm by reporter luciferase assays and real-time polymerase chain reaction. We also demonstrate that NR2F2 directly inhibits the activity of the OCT4 promoter and thus diminishes the positive feedback loop between OCT4 and miR-302. Importantly, higher reprogramming efficiencies were obtained when we reprogrammed human adipose-derived stem cells into iPSCs using four factors (KLF4, C-MYC, OCT4, and SOX2) plus miR-302 (this reprogramming cocktail is hereafter referred to as "KMOS3") when compared to using four factors ("KMOS"). Furthermore, shRNA knockdown of NR2F2 mimics the over-expression of miR-302 by also enhancing reprogramming efficiency. Interestingly, we were unable to generate iPSCs from miR-302a/b/c/d alone, which is in contrast to previous publications that have reported that miR-302 by itself can reprogram human skin cancer cells and human hair follicle cells. Taken together, these findings demonstrate that miR-302 inhibits NR2F2 and promotes pluripotency through indirect positive regulation of OCT4. This feedback loop represents an important new mechanism for understanding and inducing pluripotency in somatic cells.


Assuntos
Adipócitos/efeitos dos fármacos , Fator II de Transcrição COUP/genética , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , MicroRNAs/genética , Fator 3 de Transcrição de Octâmero/genética , Adipócitos/citologia , Adipócitos/metabolismo , Fator II de Transcrição COUP/antagonistas & inibidores , Fator II de Transcrição COUP/metabolismo , Diferenciação Celular/efeitos dos fármacos , Reprogramação Celular/efeitos dos fármacos , Reprogramação Celular/genética , Retroalimentação Fisiológica , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Fatores de Transcrição Kruppel-Like/farmacologia , Luciferases , MicroRNAs/metabolismo , MicroRNAs/farmacologia , Análise em Microsséries , Fator 3 de Transcrição de Octâmero/metabolismo , Fator 3 de Transcrição de Octâmero/farmacologia , Cultura Primária de Células , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas c-myc/farmacologia , RNA Interferente Pequeno/genética , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Fatores de Transcrição SOXB1/farmacologia , Transdução de Sinais/efeitos dos fármacos
18.
Arterioscler Thromb Vasc Biol ; 32(1): 92-102, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22034515

RESUMO

OBJECTIVE: Clinical trials of bone marrow-derived stem cell therapy for the heart have yielded variable results. The basic mechanism(s) that underlies their potential efficacy remains unknown. In the present study, we evaluated the survival kinetics, transcriptional response, and functional outcome of intramyocardial bone marrow mononuclear cell (BMMC) transplantation for cardiac repair in a murine myocardial infarction model. METHODS AND RESULTS: We used bioluminescence imaging and high-throughput transcriptional profiling to evaluate the in vivo survival kinetics and gene expression changes of transplanted BMMCs after their engraftment into ischemic myocardium. Our results demonstrate short-lived survival of cells following transplant, with less than 1% of cells surviving by 6 weeks posttransplantation. Moreover, transcriptomic analysis of BMMCs revealed nonspecific upregulation of various cell regulatory genes, with a marked downregulation of cell differentiation and maturation pathways. BMMC therapy caused limited improvement of heart function as assessed by echocardiography, invasive hemodynamics, and positron emission tomography. Histological evaluation of cell fate further confirmed findings of the in vivo cell tracking and transcriptomic analysis. CONCLUSIONS: Collectively, these data suggest that BMMC therapy, in its present iteration, may be less efficacious than once thought. Additional refinement of existing cell delivery protocols should be considered to induce better therapeutic efficacy.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Isquemia Miocárdica/terapia , Animais , Sobrevivência Celular , Ecocardiografia , Feminino , Perfilação da Expressão Gênica , Genes Reporter , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Isquemia Miocárdica/genética , Isquemia Miocárdica/patologia , Isquemia Miocárdica/fisiopatologia , Tomografia por Emissão de Pósitrons , Fatores de Tempo
20.
Thromb Haemost ; 104(1): 13-22, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20458434

RESUMO

The high mortality rate associated with cardiovascular disease is partially due to the lack of proliferative cells in the heart. Without adequate repair following myocardial infarction, progressive dilation can lead to heart failure. Stem cell therapies present one promising option for treating cardiovascular disease, though the specific mechanisms by which they benefit the heart remain unclear. Before stem cell therapies can be used safely in human populations, their biology must be investigated using innovative technologies such as multi-modality molecular imaging. The present review will discuss the basic principles, labelling techniques, clinical applications, and drawbacks associated with four major modalities: radionuclide imaging, magnetic resonance imaging, bioluminescence imaging, and fluorescence imaging.


Assuntos
Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/terapia , Transplante de Células-Tronco , Animais , Doenças Cardiovasculares/patologia , Doenças Cardiovasculares/fisiopatologia , Fluorescência , Humanos , Luminescência , Imageamento por Ressonância Magnética , Cintilografia
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