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1.
BMC Biol ; 21(1): 98, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37106386

RESUMO

BACKGROUND: Tumors are complex tissues containing collections of phenotypically diverse malignant and nonmalignant cells. We know little of the mechanisms that govern heterogeneity of tumor cells nor of the role heterogeneity plays in overcoming stresses, such as adaptation to different microenvironments. Osteosarcoma is an ideal model for studying these mechanisms-it exhibits widespread inter- and intra-tumoral heterogeneity, predictable patterns of metastasis, and a lack of clear targetable driver mutations. Understanding the processes that facilitate adaptation to primary and metastatic microenvironments could inform the development of therapeutic targeting strategies. RESULTS: We investigated single-cell RNA-sequencing profiles of 47,977 cells obtained from cell line and patient-derived xenograft models as cells adapted to growth within primary bone and metastatic lung environments. Tumor cells maintained phenotypic heterogeneity as they responded to the selective pressures imposed during bone and lung colonization. Heterogenous subsets of cells defined by distinct transcriptional profiles were maintained within bone- and lung-colonizing tumors, despite high-level selection. One prominent heterogenous feature involving glucose metabolism was clearly validated using immunofluorescence staining. Finally, using concurrent lineage tracing and single-cell transcriptomics, we found that lung colonization enriches for multiple clones with distinct transcriptional profiles that are preserved across cellular generations. CONCLUSIONS: Response to environmental stressors occurs through complex and dynamic phenotypic adaptations. Heterogeneity is maintained, even in conditions that enforce clonal selection. These findings likely reflect the influences of developmental processes promoting diversification of tumor cell subpopulations, which are retained, even in the face of selective pressures.


Assuntos
Neoplasias Ósseas , Neoplasias Pulmonares , Osteossarcoma , Humanos , Osteossarcoma/genética , Osteossarcoma/tratamento farmacológico , Osteossarcoma/patologia , Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Perfilação da Expressão Gênica , Neoplasias Ósseas/genética , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/patologia , Microambiente Tumoral/genética
2.
Tob Control ; 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37045605

RESUMO

OBJECTIVE: Determine longitudinal tobacco product discontinuation rates among youth (ages 12-17 years) in the USA between 2013 and 2019. METHODS: The Population Assessment of Tobacco and Health Study, a nationally representative, longitudinal cohort study, was used to determine annual/biennial rates of tobacco product discontinuation behaviours among youth across 2013-2019: (1) discontinuing product use (transition from past 30-day use to no past 30-day use), (2) attempting to quit product use and (3) discontinuing product use among those who attempted to quit. Discontinuing use was evaluated separately for cigarettes, electronic nicotine delivery systems (ENDS), cigars, hookah, smokeless tobacco and any tobacco. Attempting to quit and discontinuing use among those who attempted were each evaluated for cigarettes and ENDS. Generalised estimating equations were used to evaluate linear and non-linear trends in rates across the study period. RESULTS: Between 2013 and 2019, biennial rates of discontinuing tobacco product use among youth increased for cigarettes from 29% to 40%, increased for smokeless tobacco from 39% to 60%, and decreased for ENDS from 53% to 27%. By 2018/2019, rates of discontinuing use among attempters were 30% for those who used ENDS and 30% for those who smoked cigarettes. CONCLUSIONS: Findings show decreasing rates of discontinuing ENDS use among youth in the USA alongside the changing ENDS marketplace and increasing rates of discontinuing cigarette smoking and smokeless tobacco use. Findings will serve as benchmarks against which future tobacco product discontinuation rates can be compared with evaluating impacts of subsequent tobacco regulatory policies, ENDS product development and public education campaigns.

3.
Int J Obes (Lond) ; 46(2): 359-365, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34718333

RESUMO

BACKGROUND: There are limited data comparing the relative associations of various BMI metrics with adiposity and cardiometabolic risk factors in youth. OBJECTIVE: Examine correlations of 7 different BMI metrics with adiposity, cardiometabolic risk factors, and biomarkers (i.e. blood pressure, waist circumference, cholesterol, leptin, insulin, high molecular weight adiponectin, high-sensitivity c-reactive protein (hsCRP)). METHODS: This was a cross-sectional analysis of youth in all BMI categories. BMI metrics: BMI z-score (BMIz), extended BMIz (ext.BMIz), BMI percentile (BMIp), percent of the BMI 95th percentile (%BMIp95), percent of the BMI median (%BMIp50), triponderal mass index (TMI), and BMI (BMI). Correlations between these BMI metrics and adiposity, visceral adiposity, cardiometabolic risk factors and biomarkers were summarized using Pearson's correlations. RESULTS: Data from 371 children and adolescents ages 8-21 years old were included in our analysis: 52% were female; 20.2% with Class I obesity, 20.5% with Class II, and 14.3% with Class III obesity. BMIp consistently demonstrated lower correlations with adiposity, risk factors, and biomarkers (r = 0.190-0.768) than other BMI metrics. The %BMIp95 and %BMIp50 were marginally more strongly correlated with measures of adiposity as compared to other BMI metrics. The ext.BMIz did not meaningfully outperform BMIz. CONCLUSION: Out of all the BMI metrics evaluated, %BMIp95 and %BMIp50 were the most strongly correlated with measures of adiposity. %BMIp95 has the benefit of being used currently to define obesity and severe obesity in both clinical and research settings. BMIp consistently had the lowest correlations. Future research should evaluate the longitudinal stability of various BMI metrics and their relative associations with medium to long-term changes in adiposity and cardiometabolic outcomes in the context of intervention trials.


Assuntos
Adiposidade/fisiologia , Índice de Massa Corporal , Fatores de Risco Cardiometabólico , Obesidade Infantil/sangue , Adolescente , Biomarcadores/análise , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Minnesota , Obesidade Infantil/complicações , Obesidade Infantil/fisiopatologia , Adulto Jovem
4.
J Immunol ; 205(8): 2301-2311, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32938724

RESUMO

Tie2-expressing monocytes/macrophages (TEMs) are a distinct subset of proangiogenic monocytes selectively recruited to tumors in breast cancer. Because of the hypoxic nature of solid tumors, we investigated if oxygen, via hypoxia-inducible transcription factors HIF-1α and HIF-2α, regulates TEM function in the hypoxic tumor microenvironment. We orthotopically implanted PyMT breast tumor cells into the mammary fat pads of syngeneic LysMcre, HIF-1α fl/fl /LysMcre, or HIF-2α fl/fl /LysMcre mice and evaluated the tumor TEM population. There was no difference in the percentage of tumor macrophages among the mouse groups. In contrast, HIF-1α fl/fl /LysMcre mice had a significantly smaller percentage of tumor TEMs compared with control and HIF-2α fl/fl /LysMcre mice. Proangiogenic TEMs in macrophage HIF-2α-deficient tumors presented significantly more CD31+ microvessel density but exacerbated hypoxia and tissue necrosis. Reduced numbers of proangiogenic TEMs in macrophage HIF-1α-deficient tumors presented significantly less microvessel density but tumor vessels that were more functional as lectin injection revealed more perfusion, and functional electron paramagnetic resonance analysis revealed more oxygen in those tumors. Macrophage HIF-1α-deficient tumors also responded significantly to chemotherapy. These data introduce a previously undescribed and counterintuitive prohypoxia role for proangiogenic TEMs in breast cancer which is, in part, suppressed by HIF-2α.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/imunologia , Macrófagos/imunologia , Neoplasias Mamárias Experimentais/irrigação sanguínea , Neoplasias Mamárias Experimentais/imunologia , Proteínas de Neoplasias/imunologia , Receptor TIE-2/imunologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linhagem Celular Tumoral , Feminino , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/imunologia , Macrófagos/patologia , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos , Proteínas de Neoplasias/genética , Oxigênio/imunologia , Receptor TIE-2/genética
5.
Tob Control ; 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35879095

RESUMO

OBJECTIVE: To report on longitudinal tobacco product cessation rates, by product type, among adults (ages 18+ years) in the USA between 2013 and 2019. METHODS: The Population Assessment of Tobacco and Health Study, a nationally representative, longitudinal cohort study was used to report on annual and biennial rates of the following three cessation behaviours across 2013-2019: (1) discontinuing tobacco product use (ie, transition from past 30-day use to no past 30-day use), (2) attempting to quit tobacco product use and (3) quitting tobacco product use among those who attempted to quit. Each cessation behaviour was evaluated separately for cigarettes, electronic nicotine delivery systems (ENDS), cigars, hookah and smokeless tobacco. Generalised estimating equations were used to evaluate linear and nonlinear trends in cessation rates across the study period. RESULTS: Between 2013 and 2019, rates of discontinuing cigarette smoking among adults in the USA statistically increased from 16% to 18%, though these were consistently lower than rates of discontinuing use of other tobacco products. Similarly, quit attempt rates and rates of quitting among attempters increased for cigarette smokers. However, rates of discontinuing ENDS use sharply declined across the study period, from 62% to 44%. CONCLUSIONS: Findings show that tobacco product cessation rates have been changing in recent years in the USA alongside the changing tobacco product marketplace and regulatory environment, though rates of discontinuing cigarette smoking remain relatively low. Findings can serve as a benchmark against which future cessation rates can be compared with evaluate the impacts of future tobacco regulatory policies.

6.
Int J Obes (Lond) ; 45(5): 1086-1094, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33603129

RESUMO

BACKGROUND: The Child and Adult Eating Behavior Questionnaires (CEBQ, AEBQ) are established measures of eating behaviors. However, no similar measure is available for adolescents. Prior research has validated the AEBQ in adult samples, and one study has explored using the measure with adolescents. However, no studies to date have examined the validity of the AEBQ in adolescent clinical populations. Furthermore, no studies have examined associations between the AEBQ and indicators of health status in adolescents. METHODS: A total of 280 adolescents (12-17 years old, 60% female) seen in a pediatric weight management clinic completed the AEBQ at intake. Confirmatory factor analysis (CFA) was conducted with AEBQ items to evaluate the model fit of one-, two-, seven-, and eight-factor structures. Intercorrelations between scale scores from AEBQ Food Approach and Food Avoidance domains were calculated. Associations of AEBQ scales with body mass index (BMI) and binge-eating behaviors were examined using Spearman Rho correlations and independent t-tests. RESULTS: CFAs revealed that the best fitting model was a seven-factor structure excluding the Hunger scale, although overall model fit was only marginally acceptable (X2 = 980.94, CFI = 0.925, TLI = 0.915, RMSEA = 0.074). Intercorrelation analyses indicated that all Food Approach scales were significantly associated with one another (r = 0.243-0.654); Food Avoidance scales were inconsistently correlated (r = 0.034-0.439). No AEBQ scales were correlated with BMI (r = -0.101-0.082). Stronger links were found with binge eating; higher frequency binge-related behaviors were associated with higher Food Approach scores. CONCLUSIONS: The seven-factor structure of AEBQ demonstrates a marginally acceptable fit for treatment-seeking adolescents with obesity. The Food Approach scales demonstrated more convergent validity than the Food Avoidance scales. The Food Approach scales also exhibited some clinical utility for identifying patients with increased risk for binge eating, which is a common target for behavioral intervention. Implications for maximizing the AEBQ's potential for assessing eating behaviors in adolescents with obesity are discussed.


Assuntos
Comportamento Alimentar , Obesidade Infantil/terapia , Inquéritos e Questionários , Adolescente , Índice de Massa Corporal , Bulimia , Criança , Feminino , Humanos , Masculino , Minnesota
7.
J Pediatr Psychol ; 46(7): 814-823, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34142154

RESUMO

OBJECTIVE: Neonatal Intensive Care Unit (NICU) Follow-Up programs vary in the duration for which they monitor child development and neurocognitive outcomes. This study explores the early predictive value of a widely used developmental measure for intellectual functioning during early childhood to better inform whether there is value added in continued monitoring. METHODS: Participants were 209 children who had at least two assessments between the ages of 1 and 6 years old as part of NICU Follow-Up clinic. The Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) was administered when children were 1 and 2 years old and the Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV) was administered when children were 3 years and older. RESULTS: The Bayley-III at 1 year of age was a significant predictor of Bayley-III performance at age 2. Similarly, Bayley-III at ages 1 year and 2 years were significant predictors of WPPSI-IV performance. Strength of prediction was moderate with the majority of variance unexplained. Exploratory analyses examining whether early developmental abilities as assessed on the Bayley-III could identify patients at risk for poorer WPPSI-IV performance indicated appropriate specificity but inadequate sensitivity. CONCLUSIONS: This study supports ongoing assessment of children who were born with perinatal complications into at least early childhood. Assessing development only during the infant and toddler years did not sufficiently identify children who went on to have lower cognitive functioning in preschool and the early school years.


Assuntos
Deficiências do Desenvolvimento , Unidades de Terapia Intensiva Neonatal , Criança , Desenvolvimento Infantil , Pré-Escolar , Cognição , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/epidemiologia , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Gravidez
8.
Int J Cancer ; 146(11): 3184-3195, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31621900

RESUMO

Ewing sarcoma (EWS) is the second most common and aggressive type of metastatic bone tumor in adolescents and young adults. There is unmet medical need to develop and test novel pharmacological targets and novel therapies to treat EWS. Here, we found that EWS expresses high levels of a p53 isoform, delta133p53. We further determined that aberrant expression of delta133p53 induced HGF secretion resulting in tumor growth and metastasis. Thereafter, we evaluated targeting EWS tumors with HGF receptor neutralizing antibody (AMG102) in preclinical studies. Surprisingly, we found that targeting EWS tumors with HGF receptor neutralizing antibody (AMG102) in combination with GD2-specific, CAR-reengineered T-cell therapy synergistically inhibited primary tumor growth and establishment of metastatic disease in preclinical models. Furthermore, our data suggested that AMG102 treatment alone might increase leukocyte infiltration including efficient CAR-T access into tumor mass and thereby improves its antitumor activity. Together, our findings warrant the development of novel CAR-T-cell therapies that incorporate HGF receptor neutralizing antibody to improve therapeutic potency, not only in EWS but also in tumors with aberrant activation of the HGF/c-MET pathway.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Receptores de Antígenos Quiméricos/imunologia , Sarcoma de Ewing/tratamento farmacológico , Animais , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Terapia Baseada em Transplante de Células e Tecidos/métodos , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Imunoterapia Adotiva/métodos , Camundongos , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/imunologia , Sarcoma de Ewing/patologia , Transdução de Sinais/imunologia , Linfócitos T/imunologia , Microambiente Tumoral/imunologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
9.
Teach Learn Med ; 32(1): 61-70, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31315454

RESUMO

Phenomenon: Factors related to individual circumstance and organizational climate are contributing to a worsening burnout problem among providers in healthcare settings. In the academic health center, junior faculty may be at particular risk for burnout given intersecting responsibilities of clinical expertise, research rigor, teaching commitments, and service expectations. To date, much of the focus on preventing and mitigating burnout has been located at the individual level, addressing lifestyle modification and self-regulation skills. We sought to examine relationships between institutional context and burnout qualities as a means to identify opportunities for organizational leadership to address faculty burnout. Approach: Data are from a baseline survey of assistant professors (faculty with diverse ratios for clinical, research, and teaching responsibilities) located within a pediatrics department in an academic medical center. Pearson correlation coefficients and logistic regression models were used to examine relationships between institutional factors (mentorship, collaboration opportunities, feelings of empowerment, value, and support of well-being) and experiences of burnout as measured by the original 22-item Maslach Burnout Inventory (subscales: Emotional Exhaustion, Depersonalization, and Low Personal Accomplishment). Findings: Three perceived institutional characteristics were significantly associated with all three dimensions of burnout, particularly emotional exhaustion, which decreased with increasing perception of (a) empowerment to communicate professional needs, (b) feeling valued for contributions to the department, and (c) department commitment to support faculty well-being. In multivariate logistic regression models, adjusted for gender identity and years since training, increased positive perceptions of these three institutional characteristics were associated with significantly lower odds of burnout. For example, for each unit increase along a 5-point rating scale in feeling empowered to communicate needs and feeling valued for contributions to the department, the odds of meeting cutoff scores for burnout were reduced by 78% (p = .002) to 84% (p = .002), respectively. Insights: Although much of the focus on addressing burnout in healthcare settings has been on promoting coping skills and building resilience at the individual level, our findings add to a growing literature documenting a significant role for institutional leadership in identifying and facilitating strategies to promote faculty well-being. Findings also support leadership's role for improving institutional climate via creating opportunities to increase faculty perceptions of empowerment and value in the department.


Assuntos
Esgotamento Profissional/etiologia , Docentes de Medicina , Local de Trabalho/psicologia , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino
10.
J Pediatr ; 204: 71-76.e1, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30287067

RESUMO

OBJECTIVE: To investigate the relationship between adverse childhood experiences (ACEs) and weight status among adolescents. STUDY DESIGN: Data were drawn from the Minnesota Student Survey, a large (n = 105 759), statewide, anonymous survey of public school students in eighth, ninth, and eleventh grades. Self-reported height and weight were used to calculate body mass index. Multinomial logistic regression was used to examine associations between self-reported ACEs and weight status, controlling for key sociodemographic characteristics. RESULTS: ACEs were positively associated with weight status; adolescents with more ACEs were more likely to have overweight, obesity, and severe obesity than adolescents with no ACEs. Adolescents who reported an ACE were 1.2, 1.4, and 1.5 times as likely to have overweight, obesity, and severe obesity, respectively, compared with their peers with no ACEs. There was no relationship between ACEs and underweight. CONCLUSIONS: The results of this large sample of adolescents with anonymous data support the hypothesis that ACEs and obesity are strongly associated. The directionality of this relationship needs to be understood. Moreover, these findings suggest that child health professionals may need to screen for ACEs as an important aspect of clinical weight management.


Assuntos
Experiências Adversas da Infância/estatística & dados numéricos , Peso Corporal , Obesidade Infantil/etiologia , Adolescente , Índice de Massa Corporal , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Minnesota , Obesidade Infantil/epidemiologia , Fatores de Risco , Estudantes
11.
J Pediatr ; 199: 85-91, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29754863

RESUMO

OBJECTIVE: To evaluate the relationships of depression and anxiety symptoms with cardiovascular disease (CVD) risk factors and measures of vascular health in youth. STUDY DESIGN: Participants (n = 202) were 8- to 18-year-olds from a cross-sectional study evaluating cardiovascular health across a wide range of body mass index values (normal weight to severe obesity). CVD risk measurement included blood pressure, fasting lipids, glucose, insulin, carotid artery intima-media thickness, compliance and distensibility, brachial artery flow-mediated dilation, carotid-radial artery pulse wave velocity, body fat percentage, and a metabolic syndrome cluster score. Anxiety and depression symptoms were self-reported on the Screen for Child Anxiety Related Disorders and Center for Epidemiological Studies Depression Scale for Children. Two sets of adjustment variables were used in evaluation of differences between those with and without anxiety or depression symptomatology for the CVD risk factor and vascular outcomes. The first set included adjustment for Tanner stage, sex, and race; the second was additionally adjusted for percent body fat. RESULTS: Anxiety was not significantly associated with CVD risk factors or vascular health in either model. Depression was associated with high-density lipoprotein cholesterol, triglycerides, and metabolic syndrome cluster score; these relationships were attenuated when accounting for percent body fat. CONCLUSIONS: When accounting for body fat, we found no clear relationship of self-reported depression or anxiety symptoms with CVD risk factors or vascular health in youth.


Assuntos
Ansiedade/etiologia , Peso Corporal , Doenças Cardiovasculares/etiologia , Depressão/etiologia , Saúde Mental , Obesidade Infantil/complicações , Adolescente , Ansiedade/epidemiologia , Doenças Cardiovasculares/epidemiologia , Criança , Estudos Transversais , Depressão/epidemiologia , Feminino , Humanos , Incidência , Masculino , Obesidade Infantil/epidemiologia , Obesidade Infantil/psicologia , Prognóstico , Fatores de Risco , Estados Unidos/epidemiologia
13.
Implant Dent ; 25(5): 629-37, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27504534

RESUMO

PURPOSE: The objective of this study was to investigate the soft tissue response and periimplant crevicular fluid (PICF) content around platform-switched (PS) and platform-matched (PM) implants during early healing. MATERIALS AND METHODS: Nonsmokers treatment planned to receive a single implant in 2 quadrants were recruited. Two-stage implant placement protocol with 1 PM and 1 PS implant was implemented. Periimplant probing depths (PDs), modified sulcus bleeding index, and plaque indices were recorded, and PICF was collected at 1, 2, 4, and 6 weeks after abutment connection. RESULTS: PD readings were higher at week 1 than at week 6 for both groups (P = 0.0005). PD was statistically deeper in PM than in PS at week 1 (P = 0.03). There was a time-dependent decrease in total PICF volume for both groups. This decrease was statistically significant for PS (P = 0.0005), with no differences between the 2 groups at any time (P > 0.05). The decrease observed in both PM and PS for PICF interleukin 6 and macrophage inflammatory protein-1ß, and in PS for tumor necrosis factor-α (TNF-α) was statistically significant (P ≤ 0.03). TNF-α was statistically higher in PS than in PM at week 1 (P = 0.005). CONCLUSION: Within the limits of this study, it seems that periimplant soft tissue response around PM and PS implants is mostly similar during the early healing period.


Assuntos
Projeto do Implante Dentário-Pivô , Implantes Dentários , Líquido do Sulco Gengival/química , Cicatrização , Adulto , Idoso , Citocinas/análise , Projeto do Implante Dentário-Pivô/efeitos adversos , Implantes Dentários/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ferida Cirúrgica/fisiopatologia , Cicatrização/fisiologia
14.
Bioorg Med Chem Lett ; 25(20): 4593-6, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26320620

RESUMO

A one step synthesis of fluorescent 8-aryl-(7-deazaguanines) has been accomplished. Probes exhibit blue to green high quantum yield fluorescence in a variety of organic and aqueous solutions, high extinction coefficients, and large Stokes shifts often above 100 nm. The probes are highly cell permeable, and exhibit stable bright fluorescence once intracellular; therefore are suited to the design of biosensors.


Assuntos
Azaguanina/química , Azaguanina/metabolismo , Permeabilidade da Membrana Celular , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Azaguanina/análogos & derivados , Azaguanina/síntese química , Linhagem Celular Tumoral , Fluorescência , Corantes Fluorescentes/síntese química , Humanos , Células KB , Microscopia Confocal , Estrutura Molecular
15.
BMC Cancer ; 14: 825, 2014 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-25385001

RESUMO

BACKGROUND: Aggressive metastatic breast cancer cells seemingly evade surgical resection and current therapies, leading to colonization in distant organs and tissues and poor patient prognosis. Therefore, high-throughput in vitro tools allowing rapid, accurate, and novel anti-metastatic drug screening are grossly overdue. Conversely, aligned nanofiber constitutes a prominent component of the late-stage breast tumor margin extracellular matrix. This parallel suggests that the use of a synthetic ECM in the form of a nanoscale model could provide a convenient means of testing the migration potentials of cancer cells to achieve a long-term goal of providing clinicians an in vitro platform technology to test the efficacy of novel experimental anti-metastatic compounds. METHODS: Electrospinning produces highly aligned, cell-adhesive nanofiber matrices by applying a strong electric field to a polymer-containing solution. The resulting fibrous microstructure and morphology closely resembles in vivo tumor microenvironments suggesting their use in analysis of migratory potentials of metastatic cancer cells. Additionally, a novel interface with a gel-based delivery system creates CXCL12 chemotactic gradients to enhance CXCR4-expressing cell migration. RESULTS: Cellular dispersions of MCF-10A normal mammary epithelial cells or human breast cancer cells (MCF-7 and MDA-MB-231) seeded on randomly-oriented nanofiber exhibited no significant differences in total or net distance traveled as a result of the underlying topography. Cells traveled ~2-5 fold greater distances on aligned fiber. Highly-sensitive MDA-MB-231 cells displayed an 82% increase in net distance traversed in the presence of a CXCL12 gradient. In contrast, MCF-7 cells exhibited only 31% increase and MCF-10A cells showed no statistical difference versus control or vehicle conditions. MCF-10A cells displayed little sensitivity to CXCL12 gradients, while MCF-7 cells displayed early sensitivity when CXCL12 concentrations were higher. MDA-MB-231 cells displayed low relative expression levels of CXCR4, but high sensitivity resulting in 55-fold increase at late time points due to CXCL12 gradient dissipation. CONCLUSIONS: This model could create clinical impact as an in vitro diagnostic tool for rapid assessment of tumor needle biopsies to confirm metastatic tumors, their invasiveness, and allow high-throughput drug screening providing rapid development of personalized therapies.


Assuntos
Materiais Biomiméticos , Neoplasias da Mama/patologia , Movimento Celular , Nanofibras/ultraestrutura , Materiais Biomiméticos/síntese química , Neoplasias da Mama/química , Movimento Celular/efeitos dos fármacos , Quimiocina CXCL12/farmacologia , Fatores Quimiotáticos/farmacologia , Matriz Extracelular/ultraestrutura , Feminino , Ensaios de Triagem em Larga Escala , Humanos , Células MCF-7 , Invasividade Neoplásica , Metástase Neoplásica , RNA Mensageiro/análise , Receptores CXCR4/genética , Microambiente Tumoral
16.
Proc Natl Acad Sci U S A ; 108(43): 17773-8, 2011 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-21987798

RESUMO

Biallelic inactivation of cancer susceptibility gene BRCA1 leads to breast and ovarian carcinogenesis. Paradoxically, BRCA1 deficiency in mice results in early embryonic lethality, and similarly, lack of BRCA1 in human cells is thought to result in cellular lethality in view of BRCA1's essential function. To survive homozygous BRCA1 inactivation during tumorigenesis, precancerous cells must accumulate additional genetic alterations, such as p53 mutations, but this requirement for an extra genetic "hit" contradicts the two-hit theory for the accelerated carcinogenesis associated with familial cancer syndromes. Here, we show that heterozygous BRCA1 inactivation results in genomic instability in nontumorigenic human breast epithelial cells in vitro and in vivo. Using somatic cell gene targeting, we demonstrated that a heterozygous BRCA1 185delAG mutation confers impaired homology-mediated DNA repair and hypersensitivity to genotoxic stress. Heterozygous mutant BRCA1 cell clones also showed a higher degree of gene copy number loss and loss of heterozygosity in SNP array analyses. In BRCA1 heterozygous clones and nontumorigenic breast epithelial tissues from BRCA mutation carriers, FISH revealed elevated genomic instability when compared with their respective controls. Thus, BRCA1 haploinsufficiency may accelerate hereditary breast carcinogenesis by facilitating additional genetic alterations.


Assuntos
Mama/citologia , Células Epiteliais/fisiologia , Genes BRCA1 , Instabilidade Genômica/genética , Haploinsuficiência/genética , Feminino , Inativação Gênica , Instabilidade Genômica/fisiologia , Heterozigoto , Humanos , Hibridização in Situ Fluorescente , Polimorfismo de Nucleotídeo Único , Deleção de Sequência/genética
17.
Front Endocrinol (Lausanne) ; 15: 1369270, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38800488

RESUMO

Introduction: Obesity affects approximately 20% of U.S. youth. Anti-obesity medications (AOMs) are promising lifestyle modification adjuncts for obesity treatment, and topiramate is commonly prescribed in pediatric weight management clinics. It is important to determine "real-world" effectiveness of AOMs and, given shifts towards personalized approaches, characteristics potentially predicting better or worse response. We therefore sought to describe clinical effectiveness from topiramate plus lifestyle modification, and to determine if baseline phenotypic characteristics are associated with better or worse response. Methods: We performed a retrospective cohort study (2012-2020) among youth (<18 years old) followed in a U.S. academic-based weight management clinic. Baseline characteristics (i.e., body mass index (BMI), liver function tests, eating-related behaviors) and outcomes (%BMI of 95th percentile (%BMIp95), BMI, percent %BMI change, weight) were determined through review of electronic health records and clinic intake survey data. Results: Among 282 youth prescribed topiramate plus lifestyle modifications (mean baseline age 12.7 years, %BMIp95 144%), %BMIp95 and percent BMI change were statistically significantly reduced at each time point (1.5-, 3-, 6-, and 12-month %BMIp95 reductions: -2.2, -3.9, -6.6, and -9.3 percentage points, respectively; percent BMI reduction: -1.2%, -1.9%, -3.2%, and -3.4%, respectively; all p<0.01). Considering multiple comparisons, no baseline characteristics statistically significantly predicted response at any time point. Conclusions: We found that topiramate plus lifestyle modification reduced %BMIp95 and BMI among youth in a weight management clinical setting, and that no baseline characteristics evaluated were associated with response. These results should be considered preliminary given the observational nature of this study, and prospective studies are needed to further characterize clinical effectiveness and identify and confirm potential predictors of response.


Assuntos
Fármacos Antiobesidade , Índice de Massa Corporal , Obesidade Infantil , Topiramato , Humanos , Topiramato/uso terapêutico , Feminino , Masculino , Adolescente , Criança , Estudos Retrospectivos , Obesidade Infantil/terapia , Obesidade Infantil/tratamento farmacológico , Fármacos Antiobesidade/uso terapêutico , Resultado do Tratamento , Estilo de Vida , Programas de Redução de Peso/métodos , Comportamento de Redução do Risco
18.
Pediatr Obes ; : e13143, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886982

RESUMO

BACKGROUND: Anti-obesity medications (AOMs) are promising lifestyle modification (LSM) adjuncts for obesity treatment, and phentermine is commonly prescribed in paediatric weight management clinics. Determining 'real-world' AOM effectiveness and characteristics predicting response is important. OBJECTIVES: We sought to describe phentermine plus LSM effectiveness and identify baseline characteristics predicting response. METHODS: This was a retrospective cohort study among youth seen in a US academic-based weight management clinic from 2012 to 2020. Baseline characteristics (e.g., body mass index (BMI), liver transaminases, eating-related behaviours) and outcomes (%BMI of 95th percentile (%BMIp95), BMI, %BMI change, weight) were determined through electronic health records and intake surveys. RESULTS: Among 91 youth prescribed phentermine plus LSM over 8 years (mean %BMIp95 150%), %BMIp95 was statistically significantly reduced at 1.5, 3, 6 and 12 months (peak reduction 10.9 percentage points at 6 months; p < 0.001). Considering multiple comparisons, the presence of baseline elevated alanine aminotransferase was associated with statistically significant smaller 1.5-month %BMIp95 reductions (p = 0.001) and higher food responsiveness with smaller 3- (p = 0.001) and 6-month (p < 0.001) reductions. CONCLUSIONS: Phentermine plus LSM reduced %BMIp95 among youth in a weight management clinic, and baseline characteristics may help determine those more or less likely to respond. Prospective studies are needed to further characterize effectiveness and confirm response predictors.

19.
bioRxiv ; 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38260361

RESUMO

Purpose: Lung metastasis is responsible for nearly all deaths caused by osteosarcoma, the most common pediatric bone tumor. How malignant bone cells coerce the lung microenvironment to support metastatic growth is unclear. This study delineates how osteosarcoma cells educate the lung microenvironment during metastatic progression. Experimental design: Using single-cell transcriptomics (scRNA-seq), we characterized genome- and tissue-wide molecular changes induced within lung tissues by disseminated osteosarcoma cells in both immunocompetent murine models of metastasis and patient samples. We confirmed transcriptomic findings at the protein level and determined spatial relationships with multi-parameter immunofluorescence. We evaluated the ability of nintedanib to impair metastatic colonization and prevent osteosarcoma-induced education of the lung microenvironment in both immunocompetent murine osteosarcoma and immunodeficient human xenograft models. Results: Osteosarcoma cells induced acute alveolar epithelial injury upon lung dissemination. scRNA-seq demonstrated that the surrounding lung stroma adopts a chronic, non-resolving wound-healing phenotype similar to that seen in other models of lung injury. Accordingly, metastasis-associated lung demonstrated marked fibrosis, likely due to the accumulation of pathogenic, pro-fibrotic, partially-differentiated epithelial intermediates. Inhibition of fibrotic pathways with nintedanib prevented metastatic progression in multiple murine and human xenograft models. Conclusions: Our work demonstrates that osteosarcoma cells co-opt fibrosis to promote metastatic outgrowth. When harmonized with data from adult epithelial cancers, our results support a generalized model wherein aberrant mesenchymal-epithelial interactions are critical for promoting lung metastasis. Adult epithelial carcinomas induce fibrotic pathways in normal lung fibroblasts, whereas osteosarcoma, a pediatric mesenchymal tumor, exhibits fibrotic reprogramming in response to the aberrant wound-healing behaviors of an otherwise normal lung epithelium, which are induced by tumor cell interactions. Statement of translational relevance: Therapies that block metastasis have the potential to save the majority of lives lost due to solid tumors. Disseminated tumor cells must educate the foreign, inhospitable microenvironments they encounter within secondary organs to facilitate metastatic colonization. Our study elucidated that disseminated osteosarcoma cells survive within the lung by co-opting and amplifying the lung's endogenous wound healing response program. More broadly, our results support a model wherein mesenchymal-epithelial cooperation is a key driver of lung metastasis. Osteosarcoma, a pediatric mesenchymal tumor, undergoes lung epithelial induced fibrotic activation while also transforming normal lung epithelial cells towards a fibrosis promoting phenotype. Conversely, adult epithelial carcinomas activate fibrotic signaling in normal lung mesenchymal fibroblasts. Our data implicates fibrosis and abnormal wound healing as key drivers of lung metastasis across multiple tumor types that can be targeted therapeutically to disrupt metastasis progression.

20.
Pediatr Obes ; 19(4): e13101, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38290813

RESUMO

BACKGROUND: Obesity is a heterogeneous disease with variable treatment response. Identification of the unique constellation of contributors to obesity may allow for targeted interventions and improved outcomes. OBJECTIVE: Identify empirically derived phenotypes of pediatric patients with obesity based on appetitive and psychological correlates of obesity. METHODS: This cross-sectional study included patients aged 5-12 years who were treated in a weight management clinic and completed standard intake questionnaires including Child Eating Behavior Questionnaire (CEBQ), Vanderbilt ADHD Scale and Pediatric Symptom Checklist. Phenotypes were elicited using latent profile analysis of 12 indicators: eight CEBQ subscales, inattention, hyperactivity/impulsivity, internalizing and externalizing symptoms. RESULTS: Parents/guardians of 384 patients (mean age 9.8 years, mean BMI 30.3 kg/m2 ) completed the intake questionnaires. A 4-phenotype model best fits the data. Hedonic Impulsive phenotype (42.5%) exhibited high food enjoyment and hyperactivity/impulsivity. Inattentive Impulsive phenotype (27.4%) exhibited overall low food approach and high food avoid behaviours, and highest inattention. Hedonic Emotional phenotype (20.8%) scored the highest on food enjoyment, internalizing and externalizing symptoms. Picky Eating phenotype (9.3%) scored the lowest on food approach, inattention, hyperactivity/impulsivity, internalizing and externalizing symptoms. CONCLUSION: Appetitive traits and psychological symptoms appear to cluster in distinct patterns, giving rise to four unique phenotypic profiles, which, if replicated, may help inform the development of tailored treatment plans.


Assuntos
Seletividade Alimentar , Obesidade Infantil , Humanos , Criança , Estudos Transversais , Obesidade , Comportamento Alimentar/psicologia , Inquéritos e Questionários , Fenótipo , Obesidade Infantil/epidemiologia
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