Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Psychiatr Serv ; 75(2): 167-177, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37904491

RESUMO

BACKGROUND: Task sharing may involve training nonspecialist health workers (NSHWs) to deliver brief mental health interventions. This approach is promising for reducing the global mental health treatment gap. However, capacity is limited for training large cadres of frontline workers in low- and middle-income countries, hindering uptake of these interventions at scale. METHODS: The ESSENCE (enabling translation of science to service to enhance depression care) project in Madhya Pradesh, India, aims to address these challenges through two sequential randomized controlled trials. First, a training trial will evaluate the effectiveness and cost-effectiveness of digital training, compared with conventional face-to-face training, in achieving clinical competency of NSHWs in delivering an intervention for depression. This initial trial will be followed by an implementation trial aimed at evaluating the effectiveness of a remote enhanced implementation support, compared with routine implementation support, in addressing barriers to delivery of depression care in primary care facilities. RESULTS: This project involved developing and pilot testing a scalable smartphone-based program for training NSHWs to deliver a brief psychological intervention for depression screening. This initial research guided a randomized trial of a digital training approach with NSHWs to evaluate the effectiveness of this approach. This trial will be followed by a cluster-randomized trial to evaluate the effectiveness of remote implementation support in ensuring efficient delivery of depression care in primary care facilities. NEXT STEPS: Findings from these trials may inform sustainable training and implementation support models to integrate depression care into primary care for scale-up in resource-constrained settings.


Assuntos
Depressão , População Rural , Humanos , Depressão/diagnóstico , Depressão/terapia , Saúde Mental , Escalas de Graduação Psiquiátrica , Pessoal de Saúde
2.
Gene ; 896: 148024, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38040271

RESUMO

Granulomatosis with polyangiitis (GPA) is a rare systemic autoimmune disease. Major contributions of HLA genes have been reported; however, HLA typing-based diagnosis or risk prediction in GPA has not been established. We have performed a sequencing-based HLA genotyping in a north Indian GPA cohort and controls to identify clinically relevant novel associations. PR3-ANCA-positive 40 GPA patients and 40 healthy controls from north India were recruited for the study. Targeted sequencing of HLA-A,-B,-C,-DRB1,-DQB1, and -DPB1 was performed. Allelic and haplotypic associations were tested. Molecular docking of susceptibility HLA alleles with reported super-antigen epitopes was performed. The association of substituted amino acids located at the antigen-binding domain of HLA was evaluated. Genetic association of five HLA-alleles was identified in GPA. The novel association was identified for C*15:02 (p = 0.04; OR = 0.27(0.09-0.88)). The strongest association was observed for DPB1*04:01 (p < 0.0001; OR = 6.2(3.08-11.71)), previously reported in European studies. 35 of 40 GPA subjects had at least one DPB1*04:01 allele, and its significant risk was previously not reported from the Indian population. Significantly associated haplotypes DRB1*03:01-DQB1*02:01-DPB1*04:01 (p = 0.02; OR = 3.46(1.11-12.75)) and DRB1*07:01-DQB1*02:02-DPB1*04:01 (p = 0.04; OR = 3.35(0.95-14.84)) were the most frequent in GPA patients. Ranging from 89 % to 100 % of GPA patients with organ involvement can be explained by at least one DPB1*04:01 allele. A strong interaction between the HLA and three epitopes of the reported super antigen TSST-1 of Staphylococcus aureus was confirmed. Our study highlighted the potential applicability of HLA typing for screening and diagnosis of GPA. A large multi-centric study and genotype-phenotype correlation analysis among GPA patients will enable the establishment of HLA-typing based GPA diagnosis.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos , Granulomatose com Poliangiite , Cadeias beta de HLA-DP , Humanos , Alelos , Anticorpos Anticitoplasma de Neutrófilos/genética , Relevância Clínica , Epitopos/genética , Frequência do Gene , Granulomatose com Poliangiite/genética , Haplótipos , Cadeias beta de HLA-DP/genética , Cadeias beta de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Simulação de Acoplamento Molecular
3.
FASEB Bioadv ; 3(11): 877-887, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34761170

RESUMO

Methotrexate (MTX) is widely used for the treatment of rheumatoid arthritis due to its well-known anti-inflammatory role in immune cells but its impact on brown and beige adipose tissue biology has not yet been investigated. Here, we present the novel evidence that MTX treatment increases the gene expression of thermogenic genes in brown and beige adipose tissues in a fat cell autonomous manner. Furthermore, we show that treatment of mice with MTX is associated with cold resistance, improved glucose homeostasis, decreased inflammation, and reduced hepatosteatosis in high-fat diet states. Overall, our data provide novel evidence of a role of MTX on thermogenic tissues not previously appreciated.

4.
J Lipid Res ; 62: 100102, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34384787

RESUMO

Forkhead box transcription factors have been shown to be involved in various developmental and differentiation processes. In particular, members of the FoxP family have been previously characterized in depth for their participation in the regulation of lung and neuronal cell differentiation and T-cell development and function; however, their role in adipocyte functionality has not yet been investigated. Here, we report for the first time that Forkhead box P4 (FoxP4) is expressed at high levels in subcutaneous fat depots and mature thermogenic adipocytes. Through molecular and gene expression analyses, we revealed that FoxP4 is induced in response to thermogenic stimuli, both in vivo and in isolated cells, and is regulated directly by the heat shock factor protein 1 through a heat shock response element identified in the proximal promoter region of FoxP4. Further detailed analysis involving chromatin immunoprecipitation and luciferase assays demonstrated that FoxP4 directly controls the levels of uncoupling protein 1, a key regulator of thermogenesis that uncouples fatty acid oxidation from ATP production. In addition, through our gain-of-function and loss-of-function studies, we showed that FoxP4 regulates the expression of a number of classic brown and beige fat genes and affects oxygen consumption in isolated adipocytes. Overall, our data demonstrate for the first time the novel role of FoxP4 in the regulation of thermogenic adipocyte functionality.


Assuntos
Adipócitos/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Animais , Células Cultivadas , Feminino , Fatores de Transcrição Forkhead/genética , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Termogênese/genética
6.
Aging Cell ; 19(11): e13267, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33219735

RESUMO

Aging leads to a number of disorders caused by cellular senescence, tissue damage, and organ dysfunction. It has been reported that anti-inflammatory and insulin-sensitizing compounds delay, or reverse, the aging process and prevent metabolic disorders, neurodegenerative disease, and muscle atrophy, improving healthspan and extending lifespan. Here we investigated the effects of PPARγ agonists in preventing aging and increasing longevity, given their known properties in lowering inflammation and decreasing glycemia. Our molecular and physiological studies show that long-term treatment of mice at 14 months of age with low doses of the PPARγ ligand rosiglitazone (Rosi) improved glucose metabolism and mitochondrial functionality. These effects were associated with decreased inflammation and reduced tissue atrophy, improved cognitive function, and diminished anxiety- and depression-like conditions, without any adverse effects on cardiac and skeletal functionality. Furthermore, Rosi treatment of mice started when they were 14 months old was associated with lifespan extension. A retrospective analysis of the effects of the PPARγ agonist pioglitazone (Pio) on longevity showed decreased mortality in patients receiving Pio compared to those receiving a PPARγ-independent insulin secretagogue glimepiride. Taken together, these data suggest the possibility of using PPARγ agonists to promote healthy aging and extend lifespan.


Assuntos
Envelhecimento/patologia , Longevidade/efeitos dos fármacos , Doenças Metabólicas/tratamento farmacológico , PPAR gama/uso terapêutico , Animais , Humanos , Masculino , Doenças Metabólicas/mortalidade , Camundongos , PPAR gama/farmacologia , Estudos Retrospectivos , Análise de Sobrevida
8.
J Biol Chem ; 295(18): 5984-5994, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32184357

RESUMO

Heat shock factor 1 (HSF1) regulates cellular adaptation to challenges such as heat shock and oxidative and proteotoxic stresses. We have recently reported a previously unappreciated role for HSF1 in the regulation of energy metabolism in fat tissues; however, whether HSF1 is differentially expressed in adipose depots and how its levels are regulated in fat tissues remain unclear. Here, we show that HSF1 levels are higher in brown and subcutaneous fat tissues than in those in the visceral depot and that HSF1 is more abundant in differentiated, thermogenic adipocytes. Gene expression experiments indicated that HSF1 is transcriptionally regulated in fat by agents that modulate cAMP levels, by cold exposure, and by pharmacological stimulation of ß-adrenergic signaling. An in silico promoter analysis helped identify a putative response element for activating transcription factor 3 (ATF3) at -258 to -250 base pairs from the HSF1 transcriptional start site, and electrophoretic mobility shift and ChIP assays confirmed ATF3 binding to this sequence. Furthermore, functional assays disclosed that ATF3 is necessary and sufficient for HSF1 regulation. Detailed gene expression analysis revealed that ATF3 is one of the most highly induced ATFs in thermogenic tissues of mice exposed to cold temperatures or treated with the ß-adrenergic receptor agonist CL316,243 and that its expression is induced by modulators of cAMP levels in isolated adipocytes. To the best of our knowledge, our results show for the first time that HSF1 is transcriptionally controlled by ATF3 in response to classic stimuli that promote heat generation in thermogenic tissues.


Assuntos
Fator 3 Ativador da Transcrição/metabolismo , AMP Cíclico/metabolismo , Fatores de Transcrição de Choque Térmico/genética , Transdução de Sinais , Termogênese , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Feminino , Células HEK293 , Resposta ao Choque Térmico , Humanos , Masculino , Camundongos , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética
9.
J Endocr Soc ; 3(12): 2326-2340, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31745529

RESUMO

Zinc finger factors are implicated in a variety of cellular processes, including adipose tissue differentiation and thermogenesis. We have previously demonstrated that zinc finger protein 638 (ZNF638) is a transcriptional coactivator acting as an early regulator of adipogenesis in vitro. In this study, we show, to our knowledge for the first time, that, in vivo, ZNF638 abounds selectively in mature brown and subcutaneous fat tissues and in fully differentiated thermogenic adipocytes. Furthermore, gene expression studies revealed that ZNF638 is upregulated by cAMP modulators in vitro and by cold exposure and by pharmacological stimulation of ß-adrenergic signaling in vivo. In silico analysis of the upstream regulatory region of the ZNF638 gene identified two putative cAMP response elements within 500 bp of the ZNF638 transcription start site. Detailed molecular analysis involving EMSA and chromatin immunoprecipitation assays demonstrated that cAMP response element binding protein (CREB) binds to these cAMP response element regions of the ZNF638 promoter, and functional studies revealed that CREB is necessary and sufficient to regulate the levels of ZNF638 transcripts. Taken together, these results demonstrate that ZNF638 is selectively expressed in mature thermogenic adipocytes and tissues and that its induction in response to classic stimuli that promote heat generation is mediated via CREB signaling, pointing to a possible novel role of ZNF638 in brown and beige fat tissues.

10.
Nature ; 574(7777): 264-267, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31578522

RESUMO

Bacterial dysbiosis accompanies carcinogenesis in malignancies such as colon and liver cancer, and has recently been implicated in the pathogenesis of pancreatic ductal adenocarcinoma (PDA)1. However, the mycobiome has not been clearly implicated in tumorigenesis. Here we show that fungi migrate from the gut lumen to the pancreas, and that this is implicated in the pathogenesis of PDA. PDA tumours in humans and mouse models of this cancer displayed an increase in fungi of about 3,000-fold compared to normal pancreatic tissue. The composition of the mycobiome of PDA tumours was distinct from that of the gut or normal pancreas on the basis of alpha- and beta-diversity indices. Specifically, the fungal community that infiltrated PDA tumours was markedly enriched for Malassezia spp. in both mice and humans. Ablation of the mycobiome was protective against tumour growth in slowly progressive and invasive models of PDA, and repopulation with a Malassezia species-but not species in the genera Candida, Saccharomyces or Aspergillus-accelerated oncogenesis. We also discovered that ligation of mannose-binding lectin (MBL), which binds to glycans of the fungal wall to activate the complement cascade, was required for oncogenic progression, whereas deletion of MBL or C3 in the extratumoral compartment-or knockdown of C3aR in tumour cells-were both protective against tumour growth. In addition, reprogramming of the mycobiome did not alter the progression of PDA in Mbl- (also known as Mbl2) or C3-deficient mice. Collectively, our work shows that pathogenic fungi promote PDA by driving the complement cascade through the activation of MBL.


Assuntos
Adenocarcinoma/microbiologia , Adenocarcinoma/patologia , Carcinogênese , Carcinoma Ductal Pancreático/microbiologia , Carcinoma Ductal Pancreático/patologia , Microbioma Gastrointestinal/imunologia , Lectina de Ligação a Manose/imunologia , Micobioma/imunologia , Adenocarcinoma/imunologia , Animais , Carcinoma Ductal Pancreático/imunologia , Estudos de Casos e Controles , Ativação do Complemento , Complemento C3/deficiência , Complemento C3/imunologia , Progressão da Doença , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
11.
Cancer Cell ; 34(5): 757-774.e7, 2018 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-30423296

RESUMO

Pancreatic ductal adenocarcinoma (PDA) is characterized by immune tolerance and immunotherapeutic resistance. We discovered upregulation of receptor-interacting serine/threonine protein kinase 1 (RIP1) in tumor-associated macrophages (TAMs) in PDA. To study its role in oncogenic progression, we developed a selective small-molecule RIP1 inhibitor with high in vivo exposure. Targeting RIP1 reprogrammed TAMs toward an MHCIIhiTNFα+IFNγ+ immunogenic phenotype in a STAT1-dependent manner. RIP1 inhibition in TAMs resulted in cytotoxic T cell activation and T helper cell differentiation toward a mixed Th1/Th17 phenotype, leading to tumor immunity in mice and in organotypic models of human PDA. Targeting RIP1 synergized with PD1-and inducible co-stimulator-based immunotherapies. Tumor-promoting effects of RIP1 were independent of its co-association with RIP3. Collectively, our work describes RIP1 as a checkpoint kinase governing tumor immunity.


Assuntos
Carcinoma Ductal Pancreático/imunologia , Tolerância Imunológica/imunologia , Macrófagos/imunologia , Neoplasias Pancreáticas/imunologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Linfócitos T Citotóxicos/imunologia , Células Th1/imunologia , Células Th17/imunologia , Animais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Humanos , Tolerância Imunológica/genética , Células L , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Fator de Transcrição STAT1/metabolismo , Células Th1/citologia , Células Th17/citologia
12.
Oncogene ; 37(33): 4626-4632, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29743593

RESUMO

The stem cell transcription factor Sox2 is highly expressed in many cancers where it is thought to mark cancer stem cells (CSCs). In osteosarcomas, the most common bone malignancy, high Sox2 expression marks and maintains a fraction of tumor-initiating cells that show all the properties of CSC. Knockdown of Sox2 expression abolishes tumorigenicity and suppresses the CSC phenotype. Here we show that, in a mouse model of osteosarcoma, osteoblast-specific Sox2 conditional knockout (CKO) causes a drastic reduction in the frequency and onset of tumors. The rare tumors detected in the Sox2 CKO animals were all Sox2 positive, indicating that they arose from cells that had escaped Sox2 deletion. Furthermore, Sox2 inactivation in cultured osteosarcoma cells by CRISPR/CAS technology leads to a loss of viability and proliferation of the entire cell population. Inactivation of the YAP gene, a major Hippo pathway effector which is a direct Sox2 target, causes similar results and YAP overexpression rescues cells from the lethality caused by Sox2 inactivation. These effects were osteosarcoma-specific, suggesting a mechanism of cell "addiction" to Sox2-initiated pathways. The requirement of Sox2 for osteosarcoma formation as well as for the survival of the tumor cells suggests that disruption of Sox2-initiated pathways could be an effective strategy for the treatment of osteosarcoma.


Assuntos
Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Proliferação de Células/genética , Osteossarcoma/genética , Osteossarcoma/patologia , Fatores de Transcrição SOXB1/genética , Animais , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Camundongos , Camundongos Knockout , Células-Tronco Neoplásicas/patologia , Transdução de Sinais/genética
13.
Aging Cell ; 17(2)2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29383825

RESUMO

It is well established that aging is associated with metabolic dysfunction such as increased adiposity and impaired energy dissipation; however, the transcriptional mechanisms regulating energy balance during late life stages have not yet been fully elucidated. Here, we show that ablation of the nuclear receptor PPARγ specifically in inguinal fat tissue in aging mice is associated with increased fat tissue expansion and insulin resistance. These metabolic effects are accompanied by decreased thermogenesis, reduced levels of brown fat genes, and browning of subcutaneous adipose tissue. Comparative studies of the effects of PPARγ downregulation in young and mid-aged mice demonstrate a preferential regulation of brown fat gene programs in inguinal fat in an age-dependent manner. In conclusion, our study uncovers an essential role for PPARγ in maintaining energy expenditure during the aging process and suggests the possibility of targeting PPARγ to counteract age-associated metabolic dysfunction.


Assuntos
Obesidade/metabolismo , PPAR gama/metabolismo , Gordura Subcutânea/metabolismo , Adiposidade , Animais , Camundongos , PPAR gama/deficiência , Termogênese
14.
Stem Cells ; 35(12): 2340-2350, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28905448

RESUMO

The transcription factor (TF) yes-associated protein 1 (YAP1) is a major effector of the tumor suppressive Hippo signaling pathway and is also necessary to maintain pluripotency in embryonic stem cells. Elevated levels of YAP1 expression antagonize the tumor suppressive effects of the Hippo pathway that normally represses YAP1 function. High YAP1 expression is observed in several types of human cancers and is particularly prominent in cancer stem cells (CSCs). The stem cell TF Sox2, which marks and maintains CSCs in osteosarcomas (OSs), promotes YAP1 expression by binding to an intronic enhancer element and YAP1 expression is also crucial for the maintainance of OS stem cells. To further understand the regulation of YAP1 expression in OSs, we subjected the YAP1 intronic enhancer to scanning mutagenesis to identify all DNA cis-elements critical for enhancer function. Through this approach, we identified two novel TFs, GA binding protein (GABP) and myeloid zinc finger 1 (MZF1), which are essential for basal YAP1 transcription. These factors are highly expressed in OSs and bind to distinct sites in the YAP1 enhancer. Depletion of either factor leads to drastically reduced YAP1 expression and thus a reversal of stem cell properties. We also found that YAP1 can regulate the expression of Sox2 by binding to two distinct DNA binding sites upstream and downstream of the Sox2 gene. Thus, Sox2 and YAP1 reinforce each others expression to maintain stemness and tumorigenicity in OSs, but the activity of MZF1 and GABP is essential for YAP1 transcription. Stem Cells 2017;35:2340-2350.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Fator de Transcrição de Proteínas de Ligação GA/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Fosfoproteínas/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Linhagem Celular Tumoral , Humanos , Células-Tronco Neoplásicas/metabolismo , Transdução de Sinais/fisiologia , Fatores de Transcrição , Proteínas de Sinalização YAP
15.
Oncotarget ; 7(38): 60954-60970, 2016 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-27528232

RESUMO

Osteosarcoma (OS) is a highly aggressive pediatric bone cancer in which most tumor cells remain immature and fail to differentiate into bone-forming osteoblasts. However, OS cells readily respond to adipogenic stimuli suggesting they retain mesenchymal stem cell-like properties. Here we demonstrate that nuclear receptor PPARγ agonists such as the anti-diabetic, thiazolidinedione (TZD) drugs induce growth arrest and cause adipogenic differentiation in human, mouse and canine OS cells as well as in tumors in mice. Gene expression analysis reveals that TZDs induce lipid metabolism pathways while suppressing targets of the Hippo-YAP pathway, Wnt signaling and cancer-related proliferation pathways. Significantly, TZD action appears to be restricted to the high Sox2 expressing cancer stem cell population and is dependent on PPARγ expression. TZDs also affect growth and cell fate by causing the cytoplasmic sequestration of the transcription factors SOX2 and YAP that are required for tumorigenicity. Finally, we identify a TZD-regulated gene signature based on Wnt/Hippo target genes and PPARγ that predicts patient outcomes. Together, this work highlights a novel connection between PPARγ agonist in inducing adipogenesis and mimicking the tumor suppressive hippo pathway. It also illustrates the potential of drug repurposing for TZD-based differentiation therapy for osteosarcoma.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Osteossarcoma/metabolismo , PPAR gama/agonistas , PPAR gama/metabolismo , Fosfoproteínas/metabolismo , Adipócitos/citologia , Adipogenia , Animais , Ciclo Celular , Proteínas de Ciclo Celular , Diferenciação Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Cães , Via de Sinalização Hippo , Humanos , Metabolismo dos Lipídeos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Transplante de Neoplasias , Células-Tronco Neoplásicas/metabolismo , Osteossarcoma/genética , Proteínas Serina-Treonina Quinases/metabolismo , Rosiglitazona , Transdução de Sinais , Tiazolidinedionas/química , Fatores de Transcrição , Proteínas Wnt/metabolismo , Proteínas de Sinalização YAP
16.
Cancer Sci ; 106(4): 421-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25611295

RESUMO

The MYC transcription factor plays a crucial role in the regulation of cell cycle progression, apoptosis, angiogenesis, and cellular transformation. Due to its oncogenic activities and overexpression in a majority of human cancers, it is an interesting target for novel drug therapies. MYC binding to the E-box (5'-CACGTGT-3') sequence at gene promoters contributes to more than 4000 MYC-dependent transcripts. Owing to its importance in MYC regulation, we designed a novel sequence-specific DNA-binding pyrrole-imidazole (PI) polyamide, Myc-5, that recognizes the E-box consensus sequence. Bioinformatics analysis revealed that the Myc-5 binding sequence appeared in 5'- MYC binding E-box sequences at the eIF4G1, CCND1, and CDK4 gene promoters. Furthermore, ChIP coupled with detection by quantitative PCR indicated that Myc-5 has the ability to inhibit MYC binding at the target gene promoters and thus cause downregulation at the mRNA level and protein expression of its target genes in human Burkitt's lymphoma model cell line, P493.6, carrying an inducible MYC repression system and the K562 (human chronic myelogenous leukemia) cell line. Single i.v. injection of Myc-5 at 7.5 mg/kg dose caused significant tumor growth inhibition in a MYC-dependent tumor xenograft model without evidence of toxicity. We report here a compelling rationale for the identification of a PI polyamide that inhibits a part of E-box-mediated MYC downstream gene expression and is a model for showing that phenotype-associated MYC downstream gene targets consequently inhibit MYC-dependent tumor growth.


Assuntos
Linfoma de Burkitt/genética , Elementos E-Box/efeitos dos fármacos , Imidazóis/química , Nylons/química , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Pirróis/química , Animais , Apoptose/efeitos dos fármacos , Sítios de Ligação/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclina D1/genética , Quinase 4 Dependente de Ciclina/genética , Proteínas de Ligação a DNA , Elementos E-Box/genética , Fator de Iniciação Eucariótico 4G/genética , Humanos , Camundongos , Camundongos SCID , Nylons/síntese química , Regiões Promotoras Genéticas , Ligação Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/genética , Ensaios Antitumorais Modelo de Xenoenxerto
17.
PLoS One ; 4(8): e6545, 2009 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-19662095

RESUMO

BACKGROUND: The phylogeny of the indigenous Indian-specific mitochondrial DNA (mtDNA) haplogroups have been determined and refined in previous reports. Similar to mtDNA superhaplogroups M and N, a profusion of reports are also available for superhaplogroup R. However, there is a dearth of information on South Asian subhaplogroups in particular, including R8. Therefore, we ought to access the genealogy and pre-historic expansion of haplogroup R8 which is considered one of the autochthonous lineages of South Asia. METHODOLOGY/PRINCIPAL FINDINGS: Upon screening the mtDNA of 5,836 individuals belonging to 104 distinct ethnic populations of the Indian subcontinent, we found 54 individuals with the HVS-I motif that defines the R8 haplogroup. Complete mtDNA sequencing of these 54 individuals revealed two deep-rooted subclades: R8a and R8b. Furthermore, these subclades split into several fine subclades. An isofrequency contour map detected the highest frequency of R8 in the state of Orissa. Spearman's rank correlation analysis suggests significant correlation of R8 occurrence with geography. CONCLUSIONS/SIGNIFICANCE: The coalescent age of newly-characterized subclades of R8, R8a (15.4+/-7.2 Kya) and R8b (25.7+/-10.2 Kya) indicates that the initial maternal colonization of this haplogroup occurred during the middle and upper Paleolithic period, roughly around 40 to 45 Kya. These results signify that the southern part of Orissa currently inhabited by Munda speakers is likely the origin of these autochthonous maternal deep-rooted haplogroups. Our high-resolution study on the genesis of R8 haplogroup provides ample evidence of its deep-rooted ancestry among the Orissa (Austro-Asiatic) tribes.


Assuntos
DNA Mitocondrial/genética , Haplótipos , Humanos , Índia , Filogenia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...