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2.
Soc Sci Res ; 115: 102919, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37858365

RESUMO

This paper examines drivers of prejudicial attitudes among adults in the UK, focusing on the interaction between ethnic out-group size and personality traits. Leveraging data from the National Child Development Study (NCDS), we use two survey waves carried out in 2000 and 2008, just before and after the EU enlargement policy that drove a wave of immigration in the UK. We test the extent to which personality traits moderate the relationship between both absolute levels and changes in ethnic diversity at the local level, respectively, and prejudice. Key findings suggest that personality traits, in particular one's agreeableness, are important for conditioning how the proportion of non-white British in one's neighbourhood affects out-group attitudes. We observe a tendency towards polarisation in prejudicial attitudes between low-/high-agreeableness residents as their neighbourhoods become more diverse. These findings have important implications for theorising how contextual and individual characteristics jointly affect intergroup relations.


Assuntos
Individualidade , Preconceito , Adulto , Criança , Humanos , Atitude , Personalidade , Etnicidade
3.
Nature ; 540(7632): 242-247, 2016 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-27919077

RESUMO

N6-methyladenosine RNA (m6A) is a prevalent messenger RNA modification in vertebrates. Although its functions in the regulation of post-transcriptional gene expression are beginning to be unveiled, the precise roles of m6A during development of complex organisms remain unclear. Here we carry out a comprehensive molecular and physiological characterization of the individual components of the methyltransferase complex, as well as of the YTH domain-containing nuclear reader protein in Drosophila melanogaster. We identify the member of the split ends protein family, Spenito, as a novel bona fide subunit of the methyltransferase complex. We further demonstrate important roles of this complex in neuronal functions and sex determination, and implicate the nuclear YT521-B protein as a main m6A effector in these processes. Altogether, our work substantially extends our knowledge of m6A biology, demonstrating the crucial functions of this modification in fundamental processes within the context of the whole animal.


Assuntos
Adenosina/análogos & derivados , Drosophila melanogaster/fisiologia , Neurônios/fisiologia , Processos de Determinação Sexual/fisiologia , Adenosina/metabolismo , Processamento Alternativo , Animais , Comportamento Animal/fisiologia , Proteínas de Drosophila/química , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/enzimologia , Feminino , Masculino , Metiltransferases/química , Metiltransferases/metabolismo , Sistema Nervoso/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fenótipo , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Proteínas de Ligação a RNA/genética , Processos de Determinação Sexual/genética
4.
Econ Theory ; 69(4): 1147-1175, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32684667

RESUMO

We examine a two-player game with two-armed exponential bandits à la (Keller et al. in Econometrica 73:39-68, 2005), where players operate different technologies for exploring the risky option. We characterise the set of Markov perfect equilibria and show that there always exists an equilibrium in which the player with the inferior technology uses a cut-off strategy. All Markov perfect equilibria imply the same amount of experimentation but differ with respect to the expected speed of the resolution of uncertainty. If and only if the degree of asymmetry between the players is high enough, there exists a Markov perfect equilibrium in which both players use cut-off strategies. Whenever this equilibrium exists, it welfare dominates all other equilibria. This contrasts with the case of symmetric players, where there never exists a Markov perfect equilibrium in cut-off strategies.

5.
Cytogenet Genome Res ; 152(1): 9-15, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28700985

RESUMO

It has been known for many years that boys with unilateral or bilateral undescended testis (cryptorchidism) tend to have a low IQ, and those who belong to the high infertility risk (HIR) group perform less well at school than low infertility risk (LIR) patients. However, the molecular biological processes underlying this phenomenon are not understood. In this study, we report the outcome of testicular RNA profiling for genes involved in long-term memory formation. We analyzed the histology and the transcriptome of testicular biopsies from bilateral HIR cryptorchid boys, comparing those who received GnRHa treatment for 6 months after the first surgery with those who did not receive GnRHa before the second surgery. We found that GnRHa treatment alters the testicular mRNA levels of neuronal genes that are involved in long-term memory and testosterone synthesis. These data highlight a possible molecular link between cryptorchidism, impaired mini-puberty, and diminished cognitive functions. Our results are consistent with the hypothesis that hypogonadotropic hypogonadism in cryptorchid boys with altered mini-puberty may affect neuronal genes important for memory and learning, which could help explaining the negative correlation between cryptorchidism and intellectual abilities.


Assuntos
Criptorquidismo/tratamento farmacológico , Criptorquidismo/genética , Hormônio Liberador de Gonadotropina/análogos & derivados , Memória de Longo Prazo/efeitos dos fármacos , Testículo/metabolismo , Pré-Escolar , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Liberador de Gonadotropina/uso terapêutico , Humanos , Lactente , Infertilidade Masculina/genética , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência de RNA , Testículo/efeitos dos fármacos
6.
Bioconjug Chem ; 28(4): 1123-1134, 2017 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-28263563

RESUMO

Bioconjugation of RNA is a dynamic field recently reinvigorated by a surge in research on post-transcriptional modification. This work focuses on the bioconjugation of 4-thiouridine, a nucleoside that occurs as a post-transcriptional modification in bacterial RNA and is used as a metabolic label and for cross-linking purposes in eukaryotic RNA. A newly designed coumarin compound named 4-bromomethyl-7-propargyloxycoumarin (PBC) is introduced, which exhibits remarkable selectivity for 4-thiouridine. Bearing a terminal alkyne group, it is conductive to secondary bioconjugation via "click chemistry", thereby offering a wide range of preparative and analytical options. We applied PBC to quantitatively monitor the metabolic incorporation of s4U as a label into RNA and for site-specific introduction of a fluorophore into bacterial tRNA at position 8, allowing the determination of its binding constant to an RNA-modification enzyme.


Assuntos
Cumarínicos/química , RNA Bacteriano/metabolismo , Coloração e Rotulagem/métodos , Marcadores de Afinidade/síntese química , Alcinos/química , Sítios de Ligação , Química Click , Ligação Proteica , Processamento Pós-Transcricional do RNA , Tiouridina/química
7.
Methods ; 107: 48-56, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27020891

RESUMO

The analysis of RNA modifications is of high importance in order to address a wide range of biological questions. Therefore, a highly sensitive and accurate method such as liquid chromatography-tandem mass spectrometry (LC-MS/MS) has to be available. By using different LC-MS/MS procedures, it is not only possible to quantify very low amounts of RNA modifications, but also to detect probably unknown modified nucleosides. For these cases the dynamic multiple reaction monitoring and the neutral loss scan are the most common techniques. Here, we provide the whole workflow for analyzing RNA samples regarding their modification content. This includes an equipment list, the preparation of required solutions/enzymes and the creation of an internal standard or nucleoside stocks for internal or external calibration. Furthermore, we describe the preparation of RNA samples for the subsequent LC-MS/MS analysis and the corresponding analysis process.


Assuntos
Cromatografia Líquida/métodos , Processamento Pós-Transcricional do RNA/genética , RNA/isolamento & purificação , Espectrometria de Massas em Tandem/métodos , Humanos , RNA/genética
8.
Nucleic Acids Res ; 43(20): 9950-64, 2015 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26365242

RESUMO

The combination of Reverse Transcription (RT) and high-throughput sequencing has emerged as a powerful combination to detect modified nucleotides in RNA via analysis of either abortive RT-products or of the incorporation of mismatched dNTPs into cDNA. Here we simultaneously analyze both parameters in detail with respect to the occurrence of N-1-methyladenosine (m(1)A) in the template RNA. This naturally occurring modification is associated with structural effects, but it is also known as a mediator of antibiotic resistance in ribosomal RNA. In structural probing experiments with dimethylsulfate, m(1)A is routinely detected by RT-arrest. A specifically developed RNA-Seq protocol was tailored to the simultaneous analysis of RT-arrest and misincorporation patterns. By application to a variety of native and synthetic RNA preparations, we found a characteristic signature of m(1)A, which, in addition to an arrest rate, features misincorporation as a significant component. Detailed analysis suggests that the signature depends on RNA structure and on the nature of the nucleotide 3' of m(1)A in the template RNA, meaning it is sequence dependent. The RT-signature of m(1)A was used for inspection and confirmation of suspected modification sites and resulted in the identification of hitherto unknown m(1)A residues in trypanosomal tRNA.


Assuntos
Adenosina/análogos & derivados , Sequenciamento de Nucleotídeos em Larga Escala , RNA/química , Transcrição Reversa , Análise de Sequência de RNA , Adenosina/análise , Animais , Humanos , Aprendizado de Máquina , Camundongos , Homologia de Sequência do Ácido Nucleico
9.
Proc Natl Acad Sci U S A ; 111(11): 3996-4000, 2014 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-24591627

RESUMO

We assessed evidence for a contextual effect of positive intergroup contact, whereby the effect of intergroup contact between social contexts (the between-level effect) on outgroup prejudice is greater than the effect of individual-level contact within contexts (the within-level effect). Across seven large-scale surveys (five cross-sectional and two longitudinal), using multilevel analyses, we found a reliable contextual effect. This effect was found in multiple countries, operationalizing context at multiple levels (regions, districts, and neighborhoods), and with and without controlling for a range of demographic and context variables. In four studies (three cross-sectional and one longitudinal) we showed that the association between context-level contact and prejudice was largely mediated by more tolerant norms. In social contexts where positive contact with outgroups was more commonplace, norms supported such positive interactions between members of different groups. Thus, positive contact reduces prejudice on a macrolevel, whereby people are influenced by the behavior of others in their social context, not merely on a microscale, via individuals' direct experience of positive contact with outgroup members. These findings reinforce the view that contact has a significant role to play in prejudice reduction, and has great policy potential as a means to improve intergroup relations, because it can simultaneously impact large numbers of people.


Assuntos
Relações Interpessoais , Modelos Psicológicos , Preconceito/psicologia , Comportamento Social , Estudos Transversais , Humanos , Estudos Longitudinais
10.
J Struct Biol ; 194(1): 1-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26850170

RESUMO

We present a strategy to obtain milligrams of highly post-translationally modified eukaryotic proteins, transiently expressed in mammalian cells as rigid or cleavable fusions with a mammalianized version of bacterial maltose-binding protein (mMBP). This variant was engineered to combine mutations that enhance MBP solubility and affinity purification, as well as provide crystal-packing interactions for increased crystallizability. Using this cell type-independent approach, we could increase the expression of secreted and intracellular human proteins up to 200-fold. By molecular replacement with MBP, we readily determined five novel high-resolution structures of rigid fusions of targets that otherwise defied crystallization.


Assuntos
Proteínas de Bactérias/química , Proteínas Ligantes de Maltose/química , Conformação Proteica , Proteínas Recombinantes de Fusão/química , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Células CHO , Cricetinae , Cricetulus , Cristalografia por Raios X , Expressão Gênica , Células HEK293 , Humanos , Proteínas Ligantes de Maltose/genética , Proteínas Ligantes de Maltose/metabolismo , Modelos Moleculares , Mutação , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Células Sf9
11.
Child Dev ; 87(5): 1466-78, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27684399

RESUMO

Intergroup contact represents a powerful way to improve intergroup attitudes and to overcome prejudice and discrimination. However, long-term effects of intergroup contact that consider social network dynamics have rarely been studied at a young age. Study 1 validated an optimized social network approach to investigate intergroup contact (N = 6,457; Mage  = 14.91 years). Study 2 explored the developmental trajectories of intergroup contact by applying this validated network approach in a cross-sequential design (four-cohort-four-wave; N = 3,815; 13-26 years). Accelerated growth curve models showed that contact predicts the development of attitudes in adolescence, whereas acquired attitudes buffer against decreasing contact in adulthood. Findings highlight the potential of social network analysis and the developmental importance of early intergroup contact experiences.


Assuntos
Atitude , Amigos/psicologia , Processos Grupais , Desenvolvimento Humano , Modelos Psicológicos , Adolescente , Adulto , Estudos de Coortes , Europa (Continente) , Feminino , Humanos , Masculino , Apoio Social , Adulto Jovem
12.
Psychol Sci ; 25(3): 665-74, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24434239

RESUMO

This research reported here speaks to a contentious debate concerning the potential negative consequences of diversity for trust. We tested the relationship between neighborhood diversity and out-group, in-group, and neighborhood trust, taking into consideration previously untested indirect effects via intergroup contact and perceived intergroup threat. A large-scale national survey in England sampled White British majority (N = 868) and ethnic minority (N = 798) respondents from neighborhoods of varying degrees of diversity. Multilevel path analyses showed some negative direct effects of diversity for the majority group but also confirmed predictions that diversity was associated indirectly with increased trust via positive contact and lower threat. These indirect effects had positive implications for total effects of diversity, cancelling out most negative direct effects. Our findings have relevance for a growing body of research seeking to disentangle effects of diversity on trust that has so far largely ignored the key role of intergroup contact.


Assuntos
Diversidade Cultural , Etnicidade , Características de Residência , Confiança , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Inglaterra , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multinível , Racismo , Identificação Social , Percepção Social , Adulto Jovem
13.
Aggress Behav ; 40(3): 250-62, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24338684

RESUMO

Two studies tested the prediction that more positive intergroup contact would be associated with reduced aggressive intergroup action tendencies, an effect predicted to occur indirectly via reduced intergroup threat perceptions, and over and above well-established effects of contact on intergroup attitudes. Study 1, using data based on a cross-section of the general population of eight European countries (France, Germany, Hungary, Italy, the Netherlands, Poland, Portugal, and the UK; N = 7,042), examined this hypothesis in the context of aggressive action tendencies towards immigrants. Study 2, using longitudinal data obtained from a general population sample in Northern Ireland, considered effects on aggressive action tendencies between ethno-religious groups in conflict. Both studies confirmed our predictions, showing that while perceived threat was associated with greater intergroup aggressive tendencies, positive intergroup contact was indirectly associated with reduced aggressive action tendencies, via reduced intergroup threat. Findings are discussed in terms of the theoretical contributions of this research for understanding the relationship between intergroup contact and intergroup aggression.


Assuntos
Agressão/psicologia , Emigração e Imigração , Relações Interpessoais , Comportamento Social , Xenofobia/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Comparação Transcultural , Estudos Transversais , Violência Étnica/psicologia , Europa (Continente)/etnologia , Feminino , França/etnologia , Alemanha/etnologia , Processos Grupais , Humanos , Hungria/etnologia , Itália/etnologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Países Baixos/etnologia , Irlanda do Norte/etnologia , Polônia/etnologia , Portugal/etnologia , Reino Unido/etnologia , Adulto Jovem
14.
Br J Soc Psychol ; 63(1): 70-86, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37357843

RESUMO

Do White Americans prefer society to be 'colour-blind' by rising above racial identities, or 'multicultural' by openly discussing and considering them? We developed an ideology-rationality model to understand support for these diversity perspectives. Specifically, since people endorse a diversity perspective in line with their ideological values, we hypothesized that conservatism is related to a relative preference for colour blindness over multiculturalism. However, since colour blindness and multiculturalism are complex and multi-layered ideologies, we further hypothesized that the relationship between conservatism and a preference for colour blindness over multiculturalism is especially pronounced under higher levels of rationality. Results confirmed the hypotheses, either when rationality was operationalized within a dual process theory (Study 1, N = 496) or experimentally induced within a tripartite model of cognition (Study 2, N = 497). Higher levels of rationality guided White Americans high in conservatism towards a stronger preference for colour-blindness, but those low in conservatism towards a stronger preference for multiculturalism. These results suggest that among White Americans the endorsement of colour blindness versus multiculturalism stems from the interplay between ideological orientation and rationality and that rational considerations about racial policies may further divide rather than unify along ideological lines.


Assuntos
Defeitos da Visão Cromática , Preconceito , Humanos , Cegueira , Diversidade Cultural , Brancos
15.
Sci Rep ; 14(1): 2590, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38297100

RESUMO

Political knowledge is crucial for well-functioning democracies, with most scholars assuming that people at the political extremes are more knowledgeable than those at the center. Here, we adopt a data-driven approach to examine the relationship between political orientation and political knowledge by testing a series of polynomial curves in 45 countries (N = 63,544), spread over 6 continents. Contrary to the dominant perspective, we found no evidence that people at the political extremes are the most knowledgeable about politics. Rather, the most common pattern was a fourth-degree polynomial association in which those who are moderately left-wing and right-wing are more knowledgeable than people at the extremes and center of the political spectrum. This pattern was especially, though not exclusively, prevalent in Western countries. We conclude that the relationship between political orientation and political knowledge is more context-dependent and complex than assumed, and caution against (implicit) universal conclusions in social sciences.

16.
Psychon Bull Rev ; 30(1): 401-406, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36038800

RESUMO

Despite growing diversity, many individuals do not support it, posing a challenge to the successful functioning of societies, institutions, and organizations. We investigated the role of the selective exposure bias on diversity beliefs. In a large-scale nationally representative Spanish sample (N = 2,297), we conducted a time-lagged experiment with two time points 5 months apart in which we offered participants a monetary incentive to (allegedly) read attitude contradictory versus conforming information about societal support for refugees. The selective exposure bias asymmetrically predicted future diversity beliefs. Among individuals with a positive intergroup orientation, the selective exposure bias did not predict future diversity beliefs. However, among individuals with a negative intergroup orientation, the selective exposure bias predicted lower pro-diversity beliefs over time, over and above initial pro-diversity beliefs and ideological dispositions. These findings suggest that the absence of pro-diversity beliefs partly originates from a cognitive bias, holding critical implications for policymakers seeking to improve intergroup relations.


Assuntos
Atitude , Motivação , Humanos , Viés
17.
Nat Commun ; 14(1): 5846, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730813

RESUMO

Single-cell open chromatin profiling via scATAC-seq has become a mainstream measurement of open chromatin in single-cells. Here we present epiAneufinder, an algorithm that exploits the read count information from scATAC-seq data to extract genome-wide copy number alterations (CNAs) for individual cells, allowing the study of CNA heterogeneity present in a sample at the single-cell level. Using different cancer scATAC-seq datasets, we show that epiAneufinder can identify intratumor clonal heterogeneity in populations of single cells based on their CNA profiles. We demonstrate that these profiles are concordant with the ones inferred from single-cell whole genome sequencing data for the same samples. EpiAneufinder allows the inference of single-cell CNA information from scATAC-seq data, without the need of additional experiments, unlocking a layer of genomic variation which is otherwise unexplored.


Assuntos
Sequenciamento de Cromatina por Imunoprecipitação , Variações do Número de Cópias de DNA , Variações do Número de Cópias de DNA/genética , Algoritmos , Cromatina/genética
18.
Am Psychol ; 78(6): 761-774, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36892922

RESUMO

Intergroup contact provides a reliable means of reducing prejudice. Yet, critics suggested that its efficacy is undermined, even eliminated, under certain conditions. Specifically, contact may be ineffective in the face of threat, especially to (historically) advantaged groups, and discrimination, experienced especially by (historically) disadvantaged groups. We considered perceived intergroup threat and perceived discrimination as potential moderators of the effect of contact on prejudice. Two meta-analyses of correlational data from 34 studies (totaling 63,945 respondents-drawn from 67 subsamples across 19 countries) showed that contact was associated with decreased prejudice and increased out-group positivity, in cross-sectional and longitudinal designs, among advantaged and disadvantaged group members, and in both Western, Educated, Industrialized, Rich, and Democratic (WEIRD) and non-WEIRD contexts. Both perceived threat and perceived discrimination moderated the contact-attitude association, but in an unanticipated direction. Indeed, contact's beneficial effects were at least as strong among individuals high (r = .19) as among individuals low (r = .18) in perceived threat. Similarly, the effects of contact were at least as strong among those high (r = .23) as among those low (r = .20) in perceived discrimination. We conclude that contact is effective for promoting tolerant societies because it is effective even among subpopulations where achieving that goal might be most challenging. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Relações Interpessoais , Preconceito , Humanos , Estudos Transversais , Atitude , Motivação
19.
Genome Biol ; 24(1): 80, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37072791

RESUMO

BACKGROUND: Expression quantitative trait loci (eQTL) studies show how genetic variants affect downstream gene expression. Single-cell data allows reconstruction of personalized co-expression networks and therefore the identification of SNPs altering co-expression patterns (co-expression QTLs, co-eQTLs) and the affected upstream regulatory processes using a limited number of individuals. RESULTS: We conduct a co-eQTL meta-analysis across four scRNA-seq peripheral blood mononuclear cell datasets using a novel filtering strategy followed by a permutation-based multiple testing approach. Before the analysis, we evaluate the co-expression patterns required for co-eQTL identification using different external resources. We identify a robust set of cell-type-specific co-eQTLs for 72 independent SNPs affecting 946 gene pairs. These co-eQTLs are replicated in a large bulk cohort and provide novel insights into how disease-associated variants alter regulatory networks. One co-eQTL SNP, rs1131017, that is associated with several autoimmune diseases, affects the co-expression of RPS26 with other ribosomal genes. Interestingly, specifically in T cells, the SNP additionally affects co-expression of RPS26 and a group of genes associated with T cell activation and autoimmune disease. Among these genes, we identify enrichment for targets of five T-cell-activation-related transcription factors whose binding sites harbor rs1131017. This reveals a previously overlooked process and pinpoints potential regulators that could explain the association of rs1131017 with autoimmune diseases. CONCLUSION: Our co-eQTL results highlight the importance of studying context-specific gene regulation to understand the biological implications of genetic variation. With the expected growth of sc-eQTL datasets, our strategy and technical guidelines will facilitate future co-eQTL identification, further elucidating unknown disease mechanisms.


Assuntos
Doenças Autoimunes , Leucócitos Mononucleares , Humanos , Regulação da Expressão Gênica , Locos de Características Quantitativas , Proteínas Ribossômicas/genética , Doenças Autoimunes/genética , Polimorfismo de Nucleotídeo Único , Estudo de Associação Genômica Ampla
20.
Neuroendocrinology ; 96(3): 228-37, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22378048

RESUMO

BACKGROUND: Epidermal growth factor receptor (EGFR) and mammalian target of rapamycin (mTOR) are crucial targets in cancer therapy. Combined inhibition of both targets yielded synergistic effects in vitro and in vivo in several cancer entities. However, the impact of EGFR and mTOR expression and combined inhibition in neuroendocrine lung tumors other than small-cell lung cancer remains unclear. MATERIAL AND METHODS: Expression and activation of EGFR/AKT/mTOR pathway constituents were investigated in typical and atypical bronchial carcinoid (AC) tumors and large-cell neuroendocrine lung carcinomas (LCNEC) by immunohistochemistry in 110 tumor samples, and correlated with clinicopathological parameters and patient survival. Cytotoxicity of mTOR inhibitor everolimus and EGFR inhibitor erlotinib alone and in combination was assessed using growth inhibition assay in NCI-H720 AC and SHP-77 LCNEC cells. Cell cycle phase distribution was determined by FACS. Apoptosis-associated activation of caspase-3/7 was measured by Caspase-Glo® assay. Activity status of EGFR and mTOR pathway components was analyzed by immunoblotting. RESULTS: Activation of the EGFR/AKT/mTOR axis could be demonstrated in all entities and was significantly increased in higher grade tumors. Neoadjuvant chemotherapy correlated significantly with p-AKT expression and p-ERK loss. Erlotinib combined with everolimus exerted synergistic combination effects in AC and LCNEC cells by induction of apoptosis, while cell cycle phase distribution remained unaffected. These effects could be explained by synergistic downregulation of phospho-mTOR, phospho-p70S6 kinase and phospho-AKT expression by everolimus and erlotinib. CONCLUSIONS: Our study indicates that EGFR and mTOR are clinically important targets in bronchial neuroendocrine tumors, and further in vivo and clinical exploration of combined inhibition is warranted.


Assuntos
Carcinoma Broncogênico/metabolismo , Carcinoma Neuroendócrino/metabolismo , Quinazolinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sirolimo/análogos & derivados , Adolescente , Adulto , Idoso , Antineoplásicos/farmacologia , Carcinoma Broncogênico/patologia , Carcinoma Neuroendócrino/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Criança , Receptores ErbB/metabolismo , Cloridrato de Erlotinib , Everolimo , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Adulto Jovem
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