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1.
PLoS One ; 16(12): e0259301, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34855754

RESUMO

Systemic interleukin-12 (IL12) anti-tumor therapy is highly potent but has had limited utility in the clinic due to severe toxicity. Here, we present two IL12-expressing vector platforms, both of which can overcome the deficiencies of previous systemic IL12 therapies: 1) an integrating lentiviral vector, and 2) a self-replicating messenger RNA formulated with polyethyleneimine. Intratumoral administration of either IL12 vector platform resulted in recruitment of immune cells, including effector T cells and dendritic cells, and the complete remission of established tumors in multiple murine models. Furthermore, concurrent intratumoral administration of the synthetic TLR4 agonist glucopyranosyl lipid A formulated in a stable emulsion (GLA-SE) induced systemic memory T cell responses that mediated complete protection against tumor rechallenge in all survivor mice (8/8 rechallenged mice), whereas only 2/6 total rechallenged mice treated with intratrumoral IL12 monotherapy rejected the rechallenge. Taken together, expression of vectorized IL12 in combination with a TLR4 agonist represents a varied approach to broaden the applicability of intratumoral immune therapies of solid tumors.


Assuntos
Glucosídeos/farmacologia , Memória Imunológica/efeitos dos fármacos , Interleucina-12/genética , Lipídeo A/farmacologia , Neoplasias Experimentais/imunologia , Receptor 4 Toll-Like/agonistas , Animais , Linfócitos T CD8-Positivos/imunologia , Feminino , Regulação da Expressão Gênica , Vetores Genéticos/administração & dosagem , Vetores Genéticos/farmacologia , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/genética , Memória Imunológica/genética , Imunoterapia/métodos , Interferon gama/sangue , Interleucina-12/sangue , Interleucina-12/imunologia , Lentivirus/genética , Melanoma Experimental/genética , Melanoma Experimental/imunologia , Melanoma Experimental/terapia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia
2.
Vaccine ; 38(17): 3369-3377, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32088020

RESUMO

While immune checkpoint inhibition is rapidly becoming standard of care in many solid tumors, immune checkpoint inhibitors (ICIs) fail to induce clinical responses in many patients, presumably due to insufficient numbers of tumor-specific T cells in the tumor milieu. To this end, immunization protocols using viral vectors expressing tumor-associated antigens are being explored to induce T cell responses that synergize with ICIs. However, the optimal combination of vaccine and immune checkpoint regimen remains undefined. Here, a dendritic cell-targeting lentiviral vector (ZVex®) expressing the endogenous murine tyrosinase-related protein 1 (mTRP1), or the human tumor antigen NY-ESO-1, was explored as monotherapy or heterologous prime-boost (HPB) vaccine regimen together with recombinant tumor antigen in the murine B16 melanoma model. PD1/PDL1 blockade significantly enhanced ZVex/mTRP1, but not ZVex/NY-ESO-1, induced immune responses in mice, whereas the opposite effect was observed with anti-CTLA4 antibody. Anti-tumor efficacy of anti-PD1, but not anti-PDL1 or anti-CTLA4, was significantly enhanced by ZVex/mTRP1 and HPB vaccination. These results suggest mechanistic differences in the effect of checkpoint blockade on vaccine-induced immune and anti-tumor responses against self versus non-self tumor antigens, possibly due to tolerance and state of exhaustion of anti-tumor T cells.


Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Células Dendríticas/imunologia , Inibidores de Checkpoint Imunológico/farmacologia , Melanoma Experimental , Glicoproteínas de Membrana/imunologia , Proteínas de Membrana/imunologia , Oxirredutases/imunologia , Animais , Antígeno B7-H1/antagonistas & inibidores , Vetores Genéticos , Humanos , Lentivirus , Melanoma Experimental/terapia , Camundongos , Receptor de Morte Celular Programada 1/antagonistas & inibidores
3.
PLoS One ; 9(10): e108942, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25291178

RESUMO

The stimulatory NKG2D receptor on lymphocytes promotes tumor immune surveillance by targeting ligands selectively induced on cancer cells. Progressing tumors counteract by employing tactics to disable lymphocyte NKG2D. This negative dynamic is escalated as some human cancer cells co-opt expression of NKG2D, thereby complementing the presence of its ligands for autonomous stimulation of oncogenic signaling. Clinical association data imply relationships between cancer cell NKG2D and metastatic disease. Here we show that NKG2D promotes cancer cell plasticity by induction of phenotypic, molecular, and functional signatures diagnostic of the epithelial-mesenchymal transition, and of stem-like traits via induction of Sox9, a key transcriptional regulator of breast stem cell maintenance. These findings obtained with model breast tumor lines and xenotransplants were recapitulated by ex vivo cancer cells from primary invasive breast carcinomas. Thus, NKG2D may have the capacity to drive high malignancy traits underlying metastatic disease.


Assuntos
Expressão Gênica , Ligantes , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Neoplasias/genética , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal/genética , Xenoenxertos , Humanos , Camundongos , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Neoplasias/imunologia , Neoplasias/metabolismo , Células-Tronco Neoplásicas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo
4.
J Acad Nutr Diet ; 114(11): 1800-10.e2, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25131348

RESUMO

Plasminogen activator inhibitor 1 (PAI-1) is elevated in obese individuals with type 2 diabetes and may contribute, independently of traditional factors, to increased cardiovascular disease risk. Fiber intake may decrease PAI-1 levels. We examined the associations of fiber intake and its changes with PAI-1 before and during an intensive lifestyle intervention (ILI) for weight loss in 1,701 Look AHEAD (Action for Health in Diabetes) participants with dietary, fitness, and PAI-1 data at baseline and 1 year. Look AHEAD was a randomized cardiovascular disease trial in 5,145 overweight/obese patients with type 2 diabetes, comparing ILI (goal of ≥7% reduction in baseline weight) with a control arm of diabetes support and education. ILI participants were encouraged to consume vegetables, fruits, and grain products low in sugar and fat. At baseline, median fiber intake was 17.9 g/day. Each 8.3 g/day higher fiber intake was associated with a 9.2% lower PAI-1 level (P=0.008); this association persisted after weight and fitness adjustments (P=0.03). Higher baseline intake of fruit (P=0.019) and high-fiber grain and cereal (P=0.029) were related to lower PAI-1 levels. Although successful in improving weight and physical fitness at 1 year, the ILI in Look AHEAD resulted in small increases in fiber intake (4.1 g/day, compared with -2.35 g/day with diabetes support and education) that were not related to PAI-1 change (P=0.34). Only 31.3% of ILI participants (39.8% of women, 19.1% of men) met daily fiber intake recommendations. Increasing fiber intake in overweight/obese individuals with diabetes interested in weight loss is challenging. Future studies evaluating changes in fiber consumption during weight loss interventions are warranted.


Assuntos
Terapia Comportamental , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/terapia , Fibras na Dieta/uso terapêutico , Estilo de Vida , Sobrepeso/terapia , Inibidor 1 de Ativador de Plasminogênio/sangue , Índice de Massa Corporal , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Estudos de Coortes , Terapia Combinada , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/dietoterapia , Angiopatias Diabéticas/complicações , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/prevenção & controle , Cardiomiopatias Diabéticas/complicações , Cardiomiopatias Diabéticas/epidemiologia , Cardiomiopatias Diabéticas/prevenção & controle , Dieta Redutora , Exercício Físico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Sobrepeso/sangue , Sobrepeso/complicações , Sobrepeso/dietoterapia , Cooperação do Paciente , Aptidão Física , Risco , Texas/epidemiologia , Redução de Peso
5.
Psychol Rec ; 64(2): 143-150, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24976647

RESUMO

Acute effects of methylenedioxymethamphetamine (MDMA), methamphetamine (MA) and methylphenidate (MPD) were studied using a within-subject, repeated acquisition/performance procedure adapted to the Morris Swim Task. To investigate place learning, the acquisition component consisted of a hidden platform that varied in location across experimental sessions. As a control for drug effects not specific to acquisition, a performance component was included in which the hidden platform was in the same pool location in every experimental session. All three drugs increased escape latencies and swim distances in dose-dependent fashion. However, impairment in the acquisition component was generally observed only at doses that also produced impairment in the performance component, suggesting that effects were not selective to place learning. None of the drugs produced enhancement of learning or performance at any dose. Taken together, the results suggest that acute exposure to these psychomotor stimulants produce global impairment of performance in the Morris task, rather than specific deficits in place learning.

6.
Obesity (Silver Spring) ; 22(4): 1016-23, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24151217

RESUMO

OBJECTIVE: Predicting outcome in weight loss trials from baseline characteristics has proved difficult. Readiness to change is typically measured by self-report. METHODS: Performance of a behavioral task, completion of food records, from the screening period in the Look AHEAD study (n = 549 at four clinical centers) was assessed. Completeness of records was measured by the number of words and Arabic numerals (numbers) recorded per day, the number of eating episodes per day, and days per week where physical activity was noted. The primary outcome was weight loss at one year. RESULTS: In univariable analysis, both the number of words recorded and the number of numbers recorded were associated with greater weight loss. In multivariable analysis, individuals who recorded 20-26, 27-33, and ≥34 words per day lost 9.12%, 11.40%, and 12.08% of initial weight, compared to 8.98% for individuals who recorded less than 20 words per day (P values of 0.87, 0.008, and <0.001, respectively, compared to <20 words per day). CONCLUSIONS: Participants who kept more detailed food records at screening lost more weight after 1 year than individuals who kept sparser records. The use of objective behavioral screening tools may improve the assessment of weight loss readiness.


Assuntos
Registros de Dieta , Programas de Rastreamento , Obesidade/terapia , Participação do Paciente/estatística & dados numéricos , Programas de Redução de Peso , Idoso , Técnicas de Apoio para a Decisão , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Obesidade/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Autorrelato , Resultado do Tratamento , Redução de Peso/fisiologia
8.
Proc Natl Acad Sci U S A ; 108(10): 4081-6, 2011 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-21321202

RESUMO

The stimulatory natural killer group 2 member D (NKG2D) lymphocyte receptor and its tumor-associated ligands are important mediators in the immune surveillance of cancer. With advanced human tumors, however, persistent NKG2D ligand expression may favor tumor progression. We have found that cancer cells themselves express NKG2D in complex with the DNAX-activating protein 10 (DAP10) signaling adaptor. Triggering of NKG2D on ex vivo cancer cells or on tumor lines which express only few receptor complexes activates the oncogenic PI3K-protein kinase B (PKB/AKT)-mammalian target of rapamycin (mTOR) signaling axis and downstream effectors, the ribosomal protein S6 kinase 1 (S6K1) and the translation initiation factor 4E-binding protein 1 (4E-BP1). In addition, as in lymphocytes, NKG2D ligand engagement stimulates phosphorylation of JNK and ERK in MAP kinase cascades. Consistent with these signaling activities, above-threshold expression of NKG2D-DAP10 in a ligand-bearing tumor line increases its bioenergetic metabolism and proliferation, thus suggesting functional similarity between this immunoreceptor and tumor growth factor receptors. This relationship is supported by significant correlations between percentages of cancer cells that are positive for surface NKG2D and criteria of tumor progression. Hence, in a conceptual twist, these results suggest that tumor co-option of NKG2D immunoreceptor expression may complement the presence of its ligands for stimulation of tumor growth.


Assuntos
Subfamília K de Receptores Semelhantes a Lectina de Células NK/fisiologia , Neoplasias/fisiopatologia , Transdução de Sinais , Linhagem Celular Tumoral , Progressão da Doença , Ativação Enzimática , Feminino , Humanos , Masculino , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo
9.
Obesity (Silver Spring) ; 18(3): 542-7, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19661957

RESUMO

The prevalence of childhood overweight has increased significantly, with the highest rates noted among Mexican Americans. Many negative health outcomes are associated with overweight; thus, there is a need for effective weight-loss interventions tailored to this group. This study evaluated 24-month outcomes of a randomized, controlled trial involving an intensive lifestyle-based weight maintenance program targeting overweight Mexican-American children at a charter school in Houston, Texas. A total of 60 children (33 males, 55%) between the ages of 10 and 14 at or >85th percentile for BMI were recruited. Participants were randomized to an instructor-led intervention (ILI) or a self-help (SH) program, both aimed at modifying eating and physical activity behaviors using behavior modification strategies. Changes in participants' standardized BMI (zBMI) were assessed at baseline, 1, and 2 years. Tricep skinfold, total cholesterol, triglycerides, high-density lipoprotein cholesterol, and calculated low-density lipoprotein were assessed at baseline and 1 year. ILI participants showed significantly greater decreases in zBMI at 1 and 2 years (F = 26.8, P < 0.001, F = 4.1, P < 0.05, respectively) compared to SH controls. ILI participants showed greater improvements in body composition, as measured by tricep skinfold (F = 9.75, P < 0.01). Children in the ILI condition experienced benefits with respect to total cholesterol (F = 7.19, P < 0.05) and triglycerides (F = 4.35, P < 0.05) compared to children in the SH condition. Overall, the school-based intervention resulted in improved weight and clinical outcomes in overweight Mexican-American children, and zBMI was maintained over 2 years.


Assuntos
Dieta Redutora , Exercício Físico , Comportamentos Relacionados com a Saúde , Promoção da Saúde , Obesidade/terapia , Serviços de Saúde Escolar , Redução de Peso , Adolescente , Terapia Comportamental , Composição Corporal , Índice de Massa Corporal , Criança , Colesterol/sangue , Estudos de Coortes , Feminino , Educação em Saúde , Humanos , Estilo de Vida , Masculino , Americanos Mexicanos , Obesidade/epidemiologia , Avaliação de Resultados em Cuidados de Saúde , Prevalência , Autocuidado , Texas , Triglicerídeos/sangue
10.
J Am Diet Assoc ; 109(2): 330-46, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19244669

RESUMO

It is the position of the American Dietetic Association that successful weight management to improve overall health for adults requires a lifelong commitment to healthful lifestyle behaviors emphasizing sustainable and enjoyable eating practices and daily physical activity. Given the increasing incidence of overweight and obesity along with the escalating health care costs associated with weight-related illnesses, health care providers must discover how to effectively treat this complex condition. Food and nutrition professionals should stay current and skilled in weight management to assist clients in preventing weight gain, optimizing individual weight loss interventions, and achieving long-term weight loss maintenance. Using the American Dietetic Association's Evidence Analysis Process and Evidence Analysis Library, this position paper presents the current data and recommendations for weight management. The evidence supporting the value of portion control, eating frequency, meal replacements, and very-low-energy diets are discussed as well as physical activity, behavior therapy, pharmacotherapy, and surgery. Public policy changes to create environments that can assist all populations to achieve and sustain healthful lifestyle behaviors are also reviewed.


Assuntos
Peso Corporal/fisiologia , Dietética/normas , Exercício Físico/fisiologia , Comportamentos Relacionados com a Saúde , Política Nutricional , Obesidade/prevenção & controle , Medicina Baseada em Evidências , Promoção da Saúde , Humanos , Estilo de Vida , Obesidade/diagnóstico , Obesidade/dietoterapia , Obesidade/epidemiologia , Recidiva , Sociedades , Estados Unidos
11.
Int J Pediatr Obes ; 2(4): 235-41, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17852549

RESUMO

OBJECTIVE: The purpose of the present study was to determine the effect of body weight on blood lipid profile, insulin resistance and inflammatory biomarkers in Mexican-American children. METHODS: Children (13.3+/-0.1 year) were recruited from a local school and assigned to one of three groups as a volunteer sample: healthy weight (HW) (> or =10th and <85th BMI percentile; n=42), at risk of overweight (RO) (> or =85th and <95th; n =25) or overweight (OW) (> or =95th; n=42). Plasma concentrations of hsCRP, sCD14, sIL-6R, sTNF-alphaR1, sTNF-alphaR2, IL-6 and TNF-alpha were determined by ELISA. RESULTS: OW children had significantly greater plasma concentrations of hsCRP (P =0.003), sCD14 (P =0.013), sIL-6R (P =0.010), sTNF-alphaR1 (P<0.001), sTNF-alphaR2 (P=0.005), insulin (P=0.001), TC:HDL ratio (P<0.001) and triglycerides (P <0.001) than HW children. Also plasma concentrations of hsCRP, sIL-6R and sTNF-alphaR1 were significantly greater in OW compared with RO children. CONCLUSION: Overweight Mexican-American children had a higher concentration of inflammatory biomarkers than healthy weight children. To our knowledge, this is the first study to report that sCD14 is elevated in overweight compared with healthy weight Mexican-American children.


Assuntos
Mediadores da Inflamação/sangue , Americanos Mexicanos/estatística & dados numéricos , Sobrepeso/sangue , Adolescente , Biomarcadores/sangue , Glicemia/metabolismo , Peso Corporal , Proteína C-Reativa/metabolismo , Feminino , Humanos , Insulina/sangue , Resistência à Insulina , Lipídeos/sangue , Receptores de Lipopolissacarídeos/sangue , Masculino , Sobrepeso/etnologia , Sobrepeso/fisiopatologia , Receptores de Interleucina-6/sangue , Receptores Tipo I de Fatores de Necrose Tumoral/sangue , Receptores Tipo II do Fator de Necrose Tumoral/sangue , Fator de Necrose Tumoral alfa/sangue , Estados Unidos/epidemiologia , Regulação para Cima
12.
Obesity (Silver Spring) ; 14(10): 1716-23, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17062800

RESUMO

OBJECTIVE: Ghrelin is postulated to be an orexigenic signal that promotes weight regain after weight loss (WL). However, it is not known whether this putative effect of ghrelin is sustained after weight stabilization. The objective of this study was to investigate the relationship of plasma ghrelin concentrations to active WL and weight maintenance in obese subjects. RESEARCH METHODS AND PROCEDURES: This study was a randomized clinical trial, with a 12-month follow-up period. Obese Mexican-American women matched for age and BMI were randomized to a 12-month WL program (n = 25) or no intervention (controls, n = 23). Interventions included diet, exercise, and orlistat. Body weight and fasting ghrelin, leptin, insulin, and glucose concentrations were measured at baseline and 6 and 12 months. RESULTS: The WL group lost 8.5% of body weight after 6 months and maintained the new weight for the next 6 months. Ghrelin concentrations increased significantly at 6 months but returned to baseline at 12 months. Baseline ghrelin concentrations were directly related to the degree of WL achieved after 12 months. Controls experienced no change in BMI or ghrelin levels. There were no associations between plasma ghrelin and leptin or insulin concentrations. DISCUSSION: Consistent with previous results, ghrelin rises in response to WL, perhaps as a counterregulatory mechanism. However, the present results indicate that ghrelin concentrations return to baseline with sustained weight maintenance, suggesting that its effects are unlikely to regulate long-term energy balance. Baseline ghrelin concentrations are related to the degree of WL that can be achieved by active weight reduction.


Assuntos
Peso Corporal/fisiologia , Americanos Mexicanos , Obesidade/terapia , Hormônios Peptídicos/sangue , Redução de Peso/fisiologia , Adulto , Análise de Variância , Índice de Massa Corporal , Feminino , Seguimentos , Grelina , Promoção da Saúde/métodos , Humanos , Insulina/sangue , Resistência à Insulina/fisiologia , Leptina/sangue , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/fisiopatologia , Radioimunoensaio/métodos , Fatores de Tempo , Relação Cintura-Quadril
13.
Ethn Dis ; 13(1): 94-108, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12723018

RESUMO

PURPOSE: This research examined whether the migration history of overweight Mexican-American women had an independent effect on cardiovascular risk factors, or whether it was mediated by health behavior changes. DATA AND METHODS: Cross-sectional data from 390 overweight, non-diabetic Mexican-American women (aged 18 to 65 years), all recruited from Starr County, Texas, were used for this analysis. Migration history was inferred from birthplaces of subjects and relatives, and length of residence in the United States. Health behaviors included tobacco and alcohol use, sleeping, exercise, and dietary practices. The cardiovascular disease risk factor variables (CDRFVs) studied were plasma glucose, abdominal obesity, blood pressures, and blood lipids. A migration history score (MHS) was developed from factor analysis, almost equally contributed to by the 9 migration history variables. Healthy habits were defined by 6 variables, and 3 factors (blood pressures, lipids/glucose, and body fat/glucose) were used for the CDRFVs. FINDINGS AND CONCLUSION: MHS was correlated positively with socioeconomic status, and negatively with family stress. Older women had healthier drinking and sleeping habits. Women with a higher migration history score exhibited poorer exercise habits, and increased blood pressures. After adjusting for the effect of healthy exercise habits on blood pressures, the impact of migration history on blood pressures became non-significant (P>.05), leading to the conclusion that healthy exercise behaviors mediated the negative relationship of MHS with blood pressures. Age was independently positively correlated with all CDRFVs. Age also weakly moderated the negative relationship of MHS and healthy exercise habits.


Assuntos
Doenças Cardiovasculares/etnologia , Comportamentos Relacionados com a Saúde/etnologia , Americanos Mexicanos/estatística & dados numéricos , Obesidade/etnologia , Adolescente , Adulto , Fatores Etários , Idoso , Doenças Cardiovasculares/epidemiologia , Emigração e Imigração , Família , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/epidemiologia , Fatores de Risco , Fatores Socioeconômicos , Texas/epidemiologia
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