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1.
Mol Cell ; 83(20): 3720-3739.e8, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37591242

RESUMO

Fanconi anemia (FA) signaling, a key genomic maintenance pathway, is activated in response to replication stress. Here, we report that phosphorylation of the pivotal pathway protein FANCD2 by CHK1 triggers its FBXL12-dependent proteasomal degradation, facilitating FANCD2 clearance at stalled replication forks. This promotes efficient DNA replication under conditions of CYCLIN E- and drug-induced replication stress. Reconstituting FANCD2-deficient fibroblasts with phosphodegron mutants failed to re-establish fork progression. In the absence of FBXL12, FANCD2 becomes trapped on chromatin, leading to replication stress and excessive DNA damage. In human cancers, FBXL12, CYCLIN E, and FA signaling are positively correlated, and FBXL12 upregulation is linked to reduced survival in patients with high CYCLIN E-expressing breast tumors. Finally, depletion of FBXL12 exacerbated oncogene-induced replication stress and sensitized cancer cells to drug-induced replication stress by WEE1 inhibition. Collectively, our results indicate that FBXL12 constitutes a vulnerability and a potential therapeutic target in CYCLIN E-overexpressing cancers.


Assuntos
Anemia de Fanconi , Neoplasias , Humanos , Sobrevivência Celular/genética , Cromatina/genética , Ciclina E/genética , Ciclina E/metabolismo , Dano ao DNA , Reparo do DNA , Replicação do DNA/genética , Anemia de Fanconi/metabolismo , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/genética , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/metabolismo , Neoplasias/genética
2.
Blood ; 143(19): 1953-1964, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38237141

RESUMO

ABSTRACT: Sterile alpha motif and histidine-aspartate (HD) domain-containing protein 1 (SAMHD1) is a deoxynucleoside triphosphate triphosphohydrolase with ara-CTPase activity that confers cytarabine (ara-C) resistance in several hematological malignancies. Targeting SAMHD1's ara-CTPase activity has recently been demonstrated to enhance ara-C efficacy in acute myeloid leukemia. Here, we identify the transcription factor SRY-related HMG-box containing protein 11 (SOX11) as a novel direct binding partner and first known endogenous inhibitor of SAMHD1. SOX11 is aberrantly expressed not only in mantle cell lymphoma (MCL), but also in some Burkitt lymphomas. Coimmunoprecipitation of SOX11 followed by mass spectrometry in MCL cell lines identified SAMHD1 as the top SOX11 interaction partner, which was validated by proximity ligation assay. In vitro, SAMHD1 bound to the HMG box of SOX11 with low-micromolar affinity. In situ crosslinking studies further indicated that SOX11-SAMHD1 binding resulted in a reduced tetramerization of SAMHD1. Functionally, expression of SOX11 inhibited SAMHD1 ara-CTPase activity in a dose-dependent manner resulting in ara-C sensitization in cell lines and in a SOX11-inducible mouse model of MCL. In SOX11-negative MCL, SOX11-mediated ara-CTPase inhibition could be mimicked by adding the recently identified SAMHD1 inhibitor hydroxyurea. Taken together, our results identify SOX11 as a novel SAMHD1 interaction partner and its first known endogenous inhibitor with potentially important implications for clinical therapy stratification.


Assuntos
Linfoma de Célula do Manto , Proteína 1 com Domínio SAM e Domínio HD , Fatores de Transcrição SOXC , Linfoma de Célula do Manto/metabolismo , Linfoma de Célula do Manto/patologia , Linfoma de Célula do Manto/tratamento farmacológico , Linfoma de Célula do Manto/genética , Humanos , Proteína 1 com Domínio SAM e Domínio HD/metabolismo , Proteína 1 com Domínio SAM e Domínio HD/genética , Animais , Camundongos , Fatores de Transcrição SOXC/metabolismo , Fatores de Transcrição SOXC/genética , Ligação Proteica , Linhagem Celular Tumoral , Citarabina/farmacologia
3.
Blood ; 143(19): 1953-1964, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38774451

RESUMO

The sterile alpha motif and histidine-aspartate (HD) domain containing protein 1 (SAMHD1) is a deoxynucleoside triphosphate triphosphohydrolase with ara-CTPase activity that confers cytarabine (ara-C) resistance in several haematological malignancies. Targeting SAMHD1's ara-CTPase activity has recently been demonstrated to enhance ara-C efficacy in acute myeloid leukemia. Here, we identify the transcription factor SRY-related HMG-box containing protein 11 (SOX11) as a novel direct binding partner and first known endogenous inhibitor of SAMHD1. SOX11 is aberrantly expressed not only in mantle cell lymphoma (MCL), but also in some Burkitt lymphomas. Co-immunoprecipitation of SOX11 followed by mass spectrometry in MCL cell lines identified SAMHD1 as the top SOX11 interaction partner which was validated by proximity ligation assay. In vitro, SAMHD1 bound to the HMG box of SOX11 with low-micromolar affinity. In situ crosslinking studies further indicated that SOX11-SAMHD1 binding resulted in a reduced tetramerization of SAMHD1. Functionally, expression of SOX11 inhibited SAMHD1 ara-CTPase activity in a dose-dependent manner resulting in ara-C sensitization in cell lines and in a SOX11-inducible mouse model of MCL. In SOX11-negative MCL, SOX11-mediated ara-CTPase inhibition could be mimicked by adding the recently identified SAMHD1 inhibitor hydroxyurea. Taken together, our results identify SOX11 as a novel SAMHD1 interaction partner and its first known endogenous inhibitor with potentially important implications for clinical therapy stratification.


Assuntos
Linfoma de Célula do Manto , Proteína 1 com Domínio SAM e Domínio HD , Fatores de Transcrição SOXC , Linfoma de Célula do Manto/metabolismo , Linfoma de Célula do Manto/patologia , Linfoma de Célula do Manto/tratamento farmacológico , Linfoma de Célula do Manto/genética , Humanos , Proteína 1 com Domínio SAM e Domínio HD/metabolismo , Proteína 1 com Domínio SAM e Domínio HD/genética , Animais , Camundongos , Fatores de Transcrição SOXC/metabolismo , Fatores de Transcrição SOXC/genética , Ligação Proteica , Linhagem Celular Tumoral , Citarabina/farmacologia
4.
Regul Toxicol Pharmacol ; 148: 105595, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38453128

RESUMO

Several New Approach Methodologies (NAMs) for hazard assessment of skin sensitisers have been formally validated. However, data regarding their applicability on certain product classes are limited. The purpose of this project was to provide initial evidence on the applicability domain of GARD™skin and GARD™potency for the product class of agrochemical formulations. For this proof of concept, 30 liquid and 12 solid agrochemical formulations were tested in GARDskin for hazard predictions. Formulations predicted as sensitisers were further evaluated in the GARDpotency assay to determine GHS skin sensitisation category. The selected formulations were of product types, efficacy groups and sensitisation hazard classes representative of the industry's products. The performance of GARDskin was estimated by comparing results to existing in vivo animal data. The overall accuracy, sensitivity, and specificity were 76.2% (32/42), 85.0% (17/20), and 68.2% (15/22), respectively, with the predictivity for liquid formulations being slightly higher compared to the solid formulations. GARDpotency correctly subcategorized 14 out of the 17 correctly predicted sensitisers. Lack of concordance was justifiable by compositional or borderline response analysis. In conclusion, GARDskin and GARDpotency showed satisfactory performance in this initial proof-of-concept study, which supports consideration of agrochemical formulations being within the applicability domain of the test methods.


Assuntos
Agroquímicos , Dermatite Alérgica de Contato , Animais , Agroquímicos/química , Irritantes/farmacologia , Pele , Bioensaio , Estudo de Prova de Conceito , Alternativas aos Testes com Animais
5.
Regul Toxicol Pharmacol ; 149: 105597, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38460723

RESUMO

Development of New Approach Methodologies (NAMs) capable of providing a No Expected Sensitization Induction Level (NESIL) value remains a high priority for the fragrance industry for conducting a Quantitative Risk Assesment (QRA) to evaluate dermal sensitization. The in vitro GARDskin assay was recently adopted by the OECD (TG 442E) for the hazard identification of skin sensitizers. Continuous potency predictions are derived using a modified protocol that incorporates dose-response measurements. Linear regression models have been developed to predict human NESIL values. The aim of the study was to evaluate the precision and reproducibility of the continuous potency predictions from the GARDskin Dose-Response (DR) assay and its application in conducting QRA for fragrance materials using a Next Generation Risk Assessment (NGRA) framework. Results indicated that the GARDskin Dose-Response model predicted human NESIL values with a good degree of concordance with published NESIL values, which were also reproducible in 3 separate experiments. Using Isocyclocitral as an example, a QRA was conducted to determine its safe use levels in different consumer product types using a NGRA framework. This study represents a major step towards the establishment of the assay to derive NESIL values for conducting QRA evaluations for fragrance materials using a NGRA framework.


Assuntos
Relação Dose-Resposta a Droga , Perfumes , Medição de Risco/métodos , Humanos , Perfumes/toxicidade , Reprodutibilidade dos Testes , Dermatite Alérgica de Contato/etiologia , Animais , Bioensaio/métodos
6.
Proc Natl Acad Sci U S A ; 118(45)2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34737229

RESUMO

Basal-like breast cancer (BLBC) is the most aggressive subtype of breast tumors with poor prognosis and limited molecular-targeted therapy options. We show that BLBC cells have a high Cys demand and reprogrammed Cys metabolism. Patient-derived BLBC tumors from four different cohorts exhibited elevated expression of the transsulfuration enzyme cystathione ß-synthetase (CBS). CBS silencing (shCBS) made BLBC cells less invasive, proliferate slower, more vulnerable to oxidative stress and cystine (CySSCy) deprivation, prone to ferroptosis, and less responsive to HIF1-α activation under hypoxia. shCBS xenograft tumors grew slower than controls and exhibited impaired angiogenesis and larger necrotic areas. Sulfur metabolite profiling suggested that realigned sulfide/persulfide-inducing functions of CBS are important in BLBC tumor progression. Supporting this, the exclusion of serine, a substrate of CBS for producing Cys but not for producing sulfide/persulfide, did not exacerbate CySSCy deprivation-induced ferroptosis in shCBS BLBC cells. Impaired Tyr phosphorylation was detected in shCBS cells and xenografts, likely due to persulfidation-inhibited phosphatase functions. Overexpression of cystathione γ-lyase (CSE), which can also contribute to cellular sulfide/persulfide production, compensated for the loss of CBS activities, and treatment of shCBS xenografts with a CSE inhibitor further blocked tumor growth. Glutathione and protein-Cys levels were not diminished in shCBS cells or xenografts, but levels of Cys persulfidation and the persulfide-catabolizing enzyme ETHE1 were suppressed. Finally, expression of enzymes of the oxidizing Cys catabolism pathway was diminished, but expression of the persulfide-producing CARS2 was elevated in human BLBC tumors. Hence, the persulfide-producing pathways are major targetable determinants of BLBC pathology that could be therapeutically exploited.


Assuntos
Cistationina beta-Sintase/metabolismo , Cisteína/metabolismo , Neoplasias de Mama Triplo Negativas/enzimologia , Animais , Estudos de Coortes , Progressão da Doença , Feminino , Ferroptose , Humanos , Camundongos SCID , Neovascularização Patológica , Estresse Oxidativo , Sulfetos/metabolismo
7.
Plant J ; 111(2): 422-439, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35555928

RESUMO

Plants undergo photomorphogenic development in the presence of light. Photomorphogenesis is repressed by the E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1), which binds to substrates through their valine-proline (VP) motifs. The UV RESISTANCE LOCUS 8 (UVR8) photoreceptor senses UV-B and inhibits COP1 through the cooperative binding of its own VP motif and photosensing core to COP1, thereby preventing COP1 binding to substrates, including the basic leucine zipper (bZIP) transcriptional regulator ELONGATED HYPOCOTYL 5 (HY5). As a key promoter of visible light and UV-B photomorphogenesis, HY5 requires coregulators for its function. The B-box family transcription factors BBX20-BBX22 were recently described as HY5 rate-limiting coactivators under red light, but their role in UVR8 signaling was unknown. Here we describe a hypermorphic bbx21-3D mutant with enhanced photomorphogenesis, carrying a proline-to-leucine mutation at position 314 in the VP motif that impairs the interaction with and regulation by COP1. We show that BBX21 and BBX22 are UVR8-dependently stabilized after UV-B exposure, which is counteracted by a repressor induced by HY5/BBX activity. bbx20 bbx21 bbx22 mutants under UV-B are impaired in hypocotyl growth inhibition, photoprotective pigment accumulation and the expression of several HY5-dependent genes under continuous UV-B, but the immediate induction of marker genes after exposure to UV-B remains surprisingly rather unaffected. We conclude that BBX20-BBX22 contribute to HY5 activity in a subset of UV-B responses, but that additional, presently unknown, coactivators for HY5 are functional in early UVR8 signaling.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas Nucleares/genética , Prolina/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Raios Ultravioleta
8.
Phys Rev Lett ; 131(22): 221401, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101335

RESUMO

We propose that the dynamics of Kerr black holes is strongly constrained by the principle of gauge symmetry. We initiate the construction of effective field theories for Kerr black holes of any integer quantum spin s using Stückelberg fields, and show that the known three-point Kerr amplitudes are uniquely predicted using massive higher-spin gauge symmetry. This symmetry is argued to be connected to an enhanced range of validity for the Kerr effective field theories. We consider the closely related root-Kerr electromagnetic solution in parallel, for which the dynamical interactions with photons are also constrained by massive higher-spin gauge symmetry. Finally, the spin-s Compton amplitudes are analyzed, and we discuss contact-term constraints at s=2 from Ward identities.

9.
Scand J Med Sci Sports ; 33(8): 1509-1518, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37082779

RESUMO

BACKGROUND: Exercise-induced bronchoconstriction (EIB) and exercise-induced laryngeal obstruction (EILO) are common in elite athletes. Knowledge of which factors are related to incident EIB and EILO is limited. The aim of this study was to explore the course of EIB and EILO in adolescent athletes over a 2 years period and baseline characteristics related to incident EIB. METHODS: Questionnaire data on respiratory symptoms, asthma, and aeroallergy and results of objective EIB and EILO tests were collected from 58 participants (27 tested for EILO) at baseline and after 2 years (follow-up). Associations between incident EIB and baseline asthma-like symptoms, exercise-induced symptoms, fractional exhaled nitric oxide (FeNO), aeroallergy, and sex were assessed using logistic regression models. RESULTS: Ten participants had incident EIB, and eight participants had persistent EIB. Five were EIB positive at baseline but negative at follow-up, while 35 participants were EIB negative at both time points. Having incident EIB was associated with reporting waking up with chest tightness (OR = 4.38; 95% CI: 1.06, 22.09). Reporting an increased number of asthma-like symptoms increased the likelihood of incident EIB (OR = 2.78; 95% CI: 1.16, 6.58). No associations were found between exercise-induced symptoms, FeNO, aeroallergy, or sex and incident EIB. Incident EILO was found in three and persistent EILO in two of the 27 participants tested. CONCLUSION: Two in nine had incident EIB and one eighth had incident EILO, suggesting that recurrent testing for EIB and EILO may be relevant in young athletes. Particularly, EIB-negative athletes reporting multiple asthma-like symptoms could benefit from recurrent EIB testing.


Assuntos
Asma , Broncoconstrição , Adolescente , Humanos , Estudos Longitudinais , Asma/epidemiologia , Atletas , Instituições Acadêmicas
10.
Plant J ; 107(5): 1346-1362, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34160854

RESUMO

The butenolide molecule, karrikin (KAR), emerging in smoke of burned plant material, enhances light responses such as germination, inhibition of hypocotyl elongation, and anthocyanin accumulation in Arabidopsis. The KAR signaling pathway consists of KARRIKIN INSENSITIVE 2 (KAI2) and MORE AXILLARY GROWTH 2 (MAX2), which, upon activation, act in an SCF E3 ubiquitin ligase complex to target the downstream signaling components SUPPRESSOR OF MAX2 1 (SMAX1) and SMAX1-LIKE 2 (SMXL2) for degradation. How degradation of SMAX1 and SMXL2 is translated into growth responses remains unknown. Although light clearly influences the activity of KAR, the molecular connection between the two pathways is still poorly understood. Here, we demonstrate that the KAR signaling pathway promotes the activity of a transcriptional module consisting of ELONGATED HYPOCOTYL 5 (HY5), B-BOX DOMAIN PROTEIN 20 (BBX20), and BBX21. The bbx20 bbx21 mutant is largely insensitive to treatment with KAR2 , similar to a hy5 mutant, with regards to inhibition of hypocotyl elongation and anthocyanin accumulation. Detailed analysis of higher order mutants in combination with RNA-sequencing analysis revealed that anthocyanin accumulation downstream of SMAX1 and SMXL2 is fully dependent on the HY5-BBX module. However, the promotion of hypocotyl elongation by SMAX1 and SMXL2 is, in contrast to KAR2 treatment, only partially dependent on BBX20, BBX21, and HY5. Taken together, these results suggest that light- and KAR-dependent signaling intersect at the HY5-BBX transcriptional module.


Assuntos
Antocianinas/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Furanos/farmacologia , Transdução de Sinal Luminoso , Piranos/farmacologia , Fatores de Transcrição/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/fisiologia , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Germinação , Hidrolases/genética , Hidrolases/metabolismo , Hipocótilo/efeitos dos fármacos , Hipocótilo/genética , Hipocótilo/fisiologia , Hipocótilo/efeitos da radiação , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Luz , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/fisiologia , Plântula/efeitos da radiação , Fatores de Transcrição/genética
11.
Phys Rev Lett ; 128(12): 121601, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35394313

RESUMO

We present a closed formula for all Bern-Carrasco-Johansson (BCJ) numerators describing D-dimensional tree-level scattering amplitudes in a heavy-mass effective field theory with two massive particles and an arbitrary number of gluons. The corresponding gravitational amplitudes obtained via the double copy directly enter the computation of black-hole scattering and gravitational-wave emission. Our construction is based on finding a kinematic algebra for the numerators, which we relate to a quasishuffle Hopf algebra. The BCJ numerators thus obtained have a compact form and intriguing features: gauge invariance is manifest, locality is respected for massless exchange, and they contain poles corresponding to massive exchange. Counting the number of terms in a BCJ numerator for n-2 gluons gives the Fubini numbers F_{n-3}, reflecting the underlying quasishuffle Hopf algebra structure. Finally, by considering an appropriate factorization limit, the massive particles decouple, and we thus obtain a kinematic algebra and all tree-level BCJ numerators for D-dimensional pure Yang-Mills theory.

12.
Pediatr Allergy Immunol ; 33(1): e13702, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34797002

RESUMO

BACKGROUND: Self-reported exercise-induced dyspnea (EID) is common among adolescents. Possible underlying pathologies are exercise-induced bronchoconstriction (EIB) and laryngeal obstruction (EILO). The forced oscillation technique (FOT) may evaluate exercise-induced changes in airway caliber. AIM: To investigate in adolescents the relationship between EID, EIB (post-exercise fall in forced expiratory volume in 1s (FEV1 )≥10%), EILO, and post-exercise challenge changes in FOT parameters. METHODS: One hundred and forty-three subjects (97 with EID) of 13-15 years old underwent a standardized exercise challenge with FOT measurement and spirometry repeatedly performed between 2 and 30 min post-exercise. EILO was studied in a subset of 123 adolescents. Subjects showing greater changes than the healthy subgroup in the modulus of the inspiratory impedance were considered FOT responders. RESULTS: EID-nonEIB subjects presented similar post-exercise changes in all FOT parameters to nonEID-nonEIB adolescents. Changes in all FOT parameters correlated with FEV1 fall. 45 of 97 EID subjects responded neither by FEV1 nor FOT to exercise. 19 and 18 subjects responded only by FEV1 (onlyFEV1 responders) or FOT (onlyFOTresponders), respectively. Only a lower baseline forced vital capacity (FVC)%predicted and a higher FEV1 /FVC distinguished the onlyFEV1 responders from onlyFOTresponders. FOT parameters did not present specific post-exercise patterns in EILO subjects. CONCLUSION: FOT can be used to identify post-exercise changes in lower airway function. However, EID has a modest relation with both FEV1 and FOT responses, highlighting the need for objective testing. More research is needed to understand whether onlyFEV1 responders and onlyFOTresponders represent different endotypes.


Assuntos
Dispneia , Adolescente , Testes de Provocação Brônquica , Dispneia/diagnóstico , Volume Expiratório Forçado , Humanos , Oscilometria , Autorrelato , Espirometria
13.
Mol Cell Proteomics ; 19(6): 1047-1057, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32205417

RESUMO

Quantitative proteomics by mass spectrometry is widely used in biomarker research and basic biology research for investigation of phenotype level cellular events. Despite the wide application, the methodology for statistical analysis of differentially expressed proteins has not been unified. Various methods such as t test, linear model and mixed effect models are used to define changes in proteomics experiments. However, none of these methods consider the specific structure of MS-data. Choices between methods, often originally developed for other types of data, are based on compromises between features such as statistical power, general applicability and user friendliness. Furthermore, whether to include proteins identified with one peptide in statistical analysis of differential protein expression varies between studies. Here we present DEqMS, a robust statistical method developed specifically for differential protein expression analysis in mass spectrometry data. In all data sets investigated there is a clear dependence of variance on the number of PSMs or peptides used for protein quantification. DEqMS takes this feature into account when assessing differential protein expression. This allows for a more accurate data-dependent estimation of protein variance and inclusion of single peptide identifications without increasing false discoveries. The method was tested in several data sets including E. coli proteome spike-in data, using both label-free and TMT-labeled quantification. Compared with previous statistical methods used in quantitative proteomics, DEqMS showed consistently better accuracy in detecting altered protein levels compared with other statistical methods in both label-free and labeled quantitative proteomics data. DEqMS is available as an R package in Bioconductor.


Assuntos
Peptídeos/análise , Proteômica/métodos , Espectrometria de Massas em Tandem/métodos , Algoritmos , Biomarcadores/metabolismo , Linhagem Celular , Cromatografia Líquida , Receptores ErbB/antagonistas & inibidores , Escherichia coli/metabolismo , Gefitinibe/farmacologia , Humanos , Focalização Isoelétrica , Células MCF-7 , Proteoma/metabolismo , Reprodutibilidade dos Testes
14.
Mol Cell Proteomics ; 19(6): 928-943, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32234966

RESUMO

Drug resistance is a major obstacle to curative cancer therapies, and increased understanding of the molecular events contributing to resistance would enable better prediction of therapy response, as well as contribute to new targets for combination therapy. Here we have analyzed the early molecular response to epidermal growth factor receptor (EGFR) inhibition using RNA sequencing data covering 13,486 genes and mass spectrometry data covering 10,138 proteins. This analysis revealed a massive response to EGFR inhibition already within the first 24 h, including significant regulation of hundreds of genes known to control downstream signaling, such as transcription factors, kinases, phosphatases and ubiquitin E3-ligases. Importantly, this response included upregulation of key genes in multiple oncogenic signaling pathways that promote proliferation and survival, such as ERBB3, FGFR2, JAK3, and BCL6, indicating an early adaptive response to EGFR inhibition. Using a library of more than 500 approved and experimental compounds in a combination therapy screen, we could show that several kinase inhibitors with targets including JAK3 and FGFR2 increased the response to EGFR inhibitors. Further, we investigated the functional impact of BCL6 upregulation in response to EGFR inhibition using siRNA-based silencing of BCL6. Proteomics profiling revealed that BCL6 inhibited transcription of multiple target genes including p53, resulting in reduced apoptosis which implicates BCL6 upregulation as a new EGFR inhibitor treatment escape mechanism. Finally, we demonstrate that combined treatment targeting both EGFR and BCL6 act synergistically in killing lung cancer cells. In conclusion, or data indicates that multiple different adaptive mechanisms may act in concert to blunt the cellular impact of EGFR inhibition, and we suggest BCL6 as a potential target for EGFR inhibitor-based combination therapy.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteoma/metabolismo , Proteínas Proto-Oncogênicas c-bcl-6/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Benzamidas/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Cromatografia Líquida , Sinergismo Farmacológico , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , Gefitinibe/farmacologia , Perfilação da Expressão Gênica , Inativação Gênica , Humanos , Indóis/farmacologia , Neoplasias Pulmonares/genética , Proteoma/efeitos dos fármacos , Proteoma/genética , Proteínas Proto-Oncogênicas c-bcl-6/genética , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , Pirimidinas/farmacologia , RNA Interferente Pequeno , Transdução de Sinais/genética , Espectrometria de Massas em Tandem , Regulação para Cima
15.
Mol Cell Proteomics ; 19(12): 2047-2068, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32994316

RESUMO

The absence of the dystrophin protein in Duchenne muscular dystrophy (DMD) results in myofiber fragility and a plethora of downstream secondary pathologies. Although a variety of experimental therapies are in development, achieving effective treatments for DMD remains exceptionally challenging, not least because the pathological consequences of dystrophin loss are incompletely understood. Here we have performed proteome profiling in tibialis anterior muscles from two murine DMD models (mdx and mdx52) at three ages (8, 16, and 80 weeks of age), all n = 3. High-resolution isoelectric focusing liquid chromatography-tandem MS (HiRIEF-LC-MS/MS) was used to quantify the expression of 4974 proteins across all 27 samples. The two dystrophic models were found to be highly similar, whereas multiple proteins were differentially expressed relative to WT (C57BL/6) controls at each age. Furthermore, 1795 proteins were differentially expressed when samples were pooled across ages and dystrophic strains. These included numerous proteins associated with the extracellular matrix and muscle function that have not been reported previously. Pathway analysis revealed multiple perturbed pathways and predicted upstream regulators, which together are indicative of cross-talk between inflammatory, metabolic, and muscle growth pathways (e.g. TNF, INFγ, NF-κB, SIRT1, AMPK, PGC-1α, PPARs, ILK, and AKT/PI3K). Upregulation of CAV3, MVP and PAK1 protein expression was validated in dystrophic muscle by Western blot. Furthermore, MVP was upregulated during, but not required for, the differentiation of C2C12 myoblasts suggesting that this protein may affect muscle regeneration. This study provides novel insights into mutation-independent proteomic signatures characteristic of the dystrophic phenotype and its progression with aging.


Assuntos
Progressão da Doença , Distrofia Muscular de Duchenne/genética , Mutação/genética , Proteômica , Animais , Diferenciação Celular , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Mioblastos/metabolismo , Mioblastos/patologia , Reprodutibilidade dos Testes , Regulação para Cima
16.
BMC Pulm Med ; 22(1): 430, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36404311

RESUMO

BACKGROUND: Ground glass opacity (GGO) is the main HRCT feature representing alveolitis in systemic sclerosis-associated interstitial lung disease (SSc-ILD), but may also represent other conditions such as atelectasis or edema. It is unclear how much this is affected by the HRCT scan protocol used. We aimed to compare the performance of three different HRCT protocols to evaluate the degree of SSc-ILD related changes. METHODS: Eleven patients with SSc underwent chest HRCT scan by three different protocols: First, a supine scan after lying down for 15 minutes, then two scans in alternating order: A prone position scan, and a supine position scan after performing 10 deep breaths using a positive expiratory pressure (PEP) device. The HRCT scans were evaluated by the Warrick score system for ILD-related findings. RESULTS: The three HRCT protocols were compared and resulted in different mean (95% CI) Warrick scores: 9.4 (5.3-13.4) in supine after rest; 7.5 (95% CI 3.8-11.1) in prone and 7.6 (95% CI 4.2-11.1) in supine after PEP. When comparing supine after rest to prone and supine after PEP, the latter two scans had a significantly lower score (p = 0.001 for both comparisons). In all cases, only sub-scores for ground glass opacities differed, while sub-scores for fibrosis-related changes did not change. CONCLUSIONS: Different HRCT scan protocols significantly altered the Warrick severity score for SSc-ILD findings, primarily because of changes in ground glass opacities. These differences may be clinically meaningful.


Assuntos
Doenças Pulmonares Intersticiais , Escleroderma Sistêmico , Humanos , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/etiologia , Escleroderma Sistêmico/complicações , Tomografia Computadorizada por Raios X/métodos
17.
Plant J ; 103(2): 481-496, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32436306

RESUMO

Under acute stress conditions, precocious seedling development may result in the premature death of young seedlings, before they switch to autotrophic growth. The phytohormone abscisic acid (ABA) inhibits seed germination and post-germination seedling establishment under unfavorable conditions. Various environmental signals interact with the ABA pathway to optimize these early developmental events under stress. Here, we show that light availability critically influences ABA sensitivity during early seedling development. In dark conditions, the ABA-mediated inhibition of post-germination seedling establishment is strongly enhanced. COP1, a central regulator of seedling development in the dark, is necessary for this enhanced post-germination ABA sensitivity in darkness. Despite their slower germination, cop1 seedlings establish faster than wild type in the presence of ABA in both light and dark. PHY and CRY photoreceptors that inhibit COP1 activity in light modulate ABA-mediated inhibition of seedling establishment in light. Genetically, COP1 acts downstream to ABI5, a key transcriptional regulator of ABA signaling, and does not influence the transcriptional and protein levels of ABI5 during the early post-germination stages. COP1 promotes post-germination growth arrest independent of the antagonistic interaction between ABA and cytokinin signaling pathways. COP1 facilitates the binding of ABI5 on its target promoters and the ABA-mediated upregulation of these target genes is reduced in cop1-4. Together, our results suggest that COP1 positively regulates ABA signaling to inhibit post-germination seedling establishment under stress.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/fisiologia , Reguladores de Crescimento de Plantas/fisiologia , Plântula/fisiologia , Ubiquitina-Proteína Ligases/fisiologia , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/fisiologia , Citocininas/metabolismo , Escuridão , Reguladores de Crescimento de Plantas/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
18.
Eur Respir J ; 57(6)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33303532

RESUMO

We investigated the prevalence of chronic cough and its association with work ability and sick leave in the general population.Data were analysed from the Respiratory Health In Northern Europe (RHINE) III cohort (n=13 500), of which 11 252 participants had also participated in RHINE II 10 years earlier, a multicentre study in Northern Europe. Participants answered a questionnaire on chronic cough, employment factors, smoking and respiratory comorbidities.Nonproductive chronic cough was found in 7% and productive chronic cough in 9% of the participants. Participants with nonproductive cough were more often female and participants with productive cough were more often smokers and had a higher body mass index (BMI) than those without cough. Participants with chronic cough more often reported >7 days of sick leave in the preceding year than those without cough ("nonproductive cough" 21% and "productive cough" 24%; p<0.001 for comparisons with "no cough" 13%). This pattern was consistent after adjusting for age, sex, BMI, education level, smoking status and comorbidities. Participants with chronic cough at baseline reported lower work ability and more often had >7 days of sick leave at follow-up than those without cough. These associations remained significant after adjusting for cough at follow-up and other confounding factors.Chronic cough was found in around one in six participants and was associated with more sick leave. Chronic cough 10 years earlier was associated with lower work ability and sick leave at follow-up. These associations were not explained by studied comorbidities. This indication of negative effects on employment from chronic cough needs to be recognised.


Assuntos
Tosse , Licença Médica , Emprego , Europa (Continente) , Feminino , Humanos , Prevalência
19.
Phys Rev Lett ; 127(5): 051601, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34397246

RESUMO

We present a new method, exact in α^{'}, to explicitly compute string tree-level amplitudes involving one massive state and any number of massless ones. This construction relies on the so-called twisted heterotic string, which admits only gauge multiplets, a gravitational multiplet, and a single massive supermultiplet in its spectrum. In this simplified model, we determine the moduli-space integrand of all amplitudes with one massive state using Berends-Giele currents of the gauge multiplet. These integrands are then straightforwardly mapped to gravitational amplitudes in the twisted heterotic string and to the corresponding massive amplitudes of the conventional type-I and type-II superstrings.

20.
Proc Natl Acad Sci U S A ; 115(6): E1229-E1238, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29374092

RESUMO

Neuroblastoma (NB) is a remarkably heterogenic childhood tumor of the sympathetic nervous system with clinical behavior ranging from spontaneous regression to poorly differentiated tumors and metastasis. MYCN is amplified in 20% of cases and correlates with an undifferentiated, aggressive phenotype and poor prognosis. Estrogen receptor alpha (ERα) and the nerve growth factor (NGF) receptors TrkA and p75NTR are involved in neuronal differentiation and survival. We have previously shown that MYCN, via miR-18a, targets ERα in NB cells. Here, we demonstrate that interference with miR-18a or overexpression of ERα is sufficient to induce NGF signaling and to modulate both basal and NGF-induced neuronal differentiation in MYCN-amplified NB cells. Proteomic analysis confirmed an increase of neuronal features and showed that processes linked to tumor initiation and progression were inhibited upon ERα overexpression. Indeed, ectopic ERα expression was sufficient to inhibit metabolic activity and tumorigenic processes, including glycolysis, oxidative phosphorylation, cell viability, migration, and anchorage independent growth. Importantly, ERα overexpression reduced tumor burden in NB mouse models and high ERα levels were linked to improved survival in patients. In addition to ERα, several other nuclear hormone receptors (NHRs), including the glucocorticoid and the retinoic acid receptors, correlated with clinical markers for favorable and low-stage NB disease. Our data suggest that MYCN targets ERα and thereby NGF signaling to maintain an undifferentiated and aggressive phenotype. Notably, we identified the estrogen-NGF crosstalk, as well as a set of other NHRs, as potential prognostic markers and targets for therapeutic strategies against NB.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Estrogênios/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteína Proto-Oncogênica N-Myc/genética , Fator de Crescimento Neural/farmacologia , Neuroblastoma/patologia , Animais , Diferenciação Celular , Receptor alfa de Estrogênio/genética , Amplificação de Genes , Humanos , Camundongos , Proteína Proto-Oncogênica N-Myc/metabolismo , Neuroblastoma/genética , Neuroblastoma/metabolismo , Fenótipo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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