RESUMO
Food fortification with iron nanoparticles (NPs) could help prevent iron deficiency anemia, but the absorption pathway and biodistribution of iron-NPs and their bioavailability in humans is unclear. Dietary non-heme iron is physiologically absorbed via the divalent metal transporter-1 (DMT1) pathway. Using radio- iron isotope labelling in mice with a partial knockdown of intestine-specific DMT1, we assessed oral absorption and tissue biodistribution of nanostructured ferric phosphate (FePO4-NP; specific surface area [SSA] 98 m2g-1) compared to to ferrous sulfate (FeSO4), the reference compound. We show that absorption of iron from FePO4-NP appears to be largely DMT1 dependent and that its biodistribution after absorption is similar to that from FeSO4, without abnormal deposition of iron in the reticuloendothelial system. Furthermore, we demonstrate high bioavailability from iron NPs in iron deficient anemic women in a randomized, cross-over study using stable-isotope labelling: absorption and subsequent erythrocyte iron utilization from two 57Fe-labeled FePO4-NP with SSAs of 98 m2g-1 and 188 m2g-1 was 2.8-fold and 5.4-fold higher than from bulk FePO4 with an SSA of 25 m2g-1 (P < 0.001) when added to a rice and vegetable meal consumed by iron deficient anemic women. The FePO4-NP 188 m2g-1 achieved 72% relative bioavailability compared to FeSO4. These data suggest FePO4-NPs may be useful for nutritional applications.
Assuntos
Anemia Ferropriva/dietoterapia , Proteínas de Transporte de Cátions/genética , Compostos Férricos/farmacologia , Ferro/metabolismo , Adsorção/efeitos dos fármacos , Adulto , Anemia Ferropriva/genética , Anemia Ferropriva/metabolismo , Anemia Ferropriva/patologia , Animais , Disponibilidade Biológica , Suplementos Nutricionais/efeitos adversos , Feminino , Compostos Férricos/química , Compostos Ferrosos/farmacologia , Alimentos Fortificados/efeitos adversos , Humanos , Ferro/farmacologia , Radioisótopos de Ferro/farmacologia , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Camundongos , Nanoestruturas/uso terapêutico , Adulto JovemAssuntos
Falso Aneurisma , Falso Aneurisma/terapia , Humanos , Injeções , Mesentério , Stents , Trombina/uso terapêuticoRESUMO
Displacement experiments have demonstrated that experienced migratory birds translocated thousands of kilometers away from their migratory corridor can orient toward and ultimately reach their intended destinations.1 This implies that they are capable of "true navigation," commonly defined2-4 as the ability to return to a known destination after displacement to an unknown location without relying on familiar surroundings, cues that emanate from the destination, or information collected during the outward journey.5-13 In birds, true navigation appears to require previous migratory experience5-7,14,15 (but see Kishkinev et al.16 and Piersma et al.17). It is generally assumed that, to correct for displacements outside the familiar area, birds initially gather information within their year-round distribution range, learn predictable spatial gradients of environmental cues within it, and extrapolate from those to unfamiliar magnitudes-the gradient hypothesis.6,9,18-22 However, the nature of the cues and evidence for actual extrapolation remain elusive. Geomagnetic cues (inclination, declination, and total intensity) provide predictable spatial gradients across large parts of the globe and could serve for navigation. We tested the orientation of long-distance migrants, Eurasian reed warblers, exposing them to geomagnetic cues of unfamiliar magnitude encountered beyond their natural distribution range. The birds demonstrated re-orientation toward their migratory corridor as if they were translocated to the corresponding location but only when all naturally occurring magnetic cues were presented, not when declination was changed alone. This result represents direct evidence for migratory birds' ability to navigate using geomagnetic cues extrapolated beyond their previous experience.
Assuntos
Migração Animal , Campos Magnéticos , Aves Canoras , Animais , Sinais (Psicologia)RESUMO
OBJECTIVE: Many African infants receiving iron fortificants also receive antibiotics. Antibiotic efficacy against enteropathogens may be modified by high colonic iron concentrations. In this study, we evaluated the effect of antibiotics on the infant gut microbiome and diarrhoea when given with or without iron-containing micronutrient powders (MNPs). DESIGN: In a controlled intervention trial, four groups of community-dwelling infants (n=28; aged 8-10 months) received either: (A) antibiotics for 5 days and iron-MNPs for 40 days (Fe+Ab+); (B) antibiotics and no-iron-MNPs (Fe-Ab+); (C) no antibiotics and iron-MNPs (Fe+Ab-); or (D) no antibiotics and no-iron-MNPs (Fe-Ab-). We collected a faecal sample before the first antibiotic dose (D0) and after 5, 10, 20 and 40 days (D5-D40) to assess the gut microbiome composition by 16S profiling, enteropathogens by quantitative PCR, faecal calprotectin and pH and assessed morbidity over the 40-day study period. RESULTS: In Fe+Ab+, there was a decrease in Bifidobacterium abundances (p<0.05), but no decrease in Fe-Ab+. In Fe-Ab+, there was a decrease in abundances of pathogenic Escherichia coli (p<0.05), but no decrease in Fe+Ab+. In Fe-Ab+, there was a decrease in pH (p<0.05), but no decrease in Fe+Ab+. Longitudinal prevalence of diarrhoea was higher in Fe+Ab+ (19.6%) compared with Fe-Ab+ (12.4%) (p=0.04) and compared with Fe+Ab- (5.2%) (p=0.00). CONCLUSION: Our findings need confirmation in a larger study but suggest that, in African infants, iron fortification modifies the response to broad-spectrum antibiotics: iron may reduce their efficacy against potential enteropathogens, particularly pathogenic E. coli, and may increase risk for diarrhoea. TRIAL REGISTRATION NUMBER: NCT02118402; Pre-results.
Assuntos
Antibacterianos/efeitos adversos , Diarreia/microbiologia , Diarreia/prevenção & controle , Microbioma Gastrointestinal/efeitos dos fármacos , Ferro/farmacologia , Micronutrientes/farmacologia , Bifidobacterium/isolamento & purificação , Escherichia coli/isolamento & purificação , Feminino , Humanos , Concentração de Íons de Hidrogênio , Lactente , Quênia , Complexo Antígeno L1 Leucocitário/análise , Masculino , Reação em Cadeia da Polimerase , Pós , Resultado do TratamentoRESUMO
Nanomaterial engineering provides an important technological advance that offers substantial benefits for applications not only in the production and processing, but also in the packaging and storage of food. An expanding commercialization of nanomaterials as part of the modern diet will substantially increase their oral intake worldwide. While the risk of particle inhalation received much attention, gaps of knowledge exist regarding possible adverse health effects due to gastrointestinal exposure. This problem is highlighted by pigment-grade titanium dioxide (TiO2), which confers a white color and increased opacity with an optimal particle diameter of 200-300 nm. However, size distribution analyses showed that batches of food-grade TiO2 always comprise a nano-sized fraction as inevitable byproduct of the manufacturing processes. Submicron-sized TiO2 particles, in Europe listed as E 171, are widely used as a food additive although the relevant risk assessment has never been satisfactorily completed. For example, it is not possible to derive a safe daily intake of TiO2 from the available long-term feeding studies in rodents. Also, the use of TiO2 particles in the food sector leads to highest exposures in children, but only few studies address the vulnerability of this particular age group. Extrapolation of animal studies to humans is also problematic due to knowledge gaps as to local gastrointestinal effects of TiO2 particles, primarily on the mucosa and the gut-associated lymphoid system. Tissue distributions after oral administration of TiO2 differ from other exposure routes, thus limiting the relevance of data obtained from inhalation or parenteral injections. Such difficulties and uncertainties emerging in the retrospective assessment of TiO2 particles exemplify the need for a fit-to-purpose data requirement for the future evaluation of novel nano-sized or submicron-sized particles added deliberately to food.
Assuntos
Aditivos Alimentares/toxicidade , Titânio/toxicidade , Animais , Células Cultivadas , Exposição Ambiental , Humanos , Camundongos , Testes de ToxicidadeRESUMO
BACKGROUND: A well-functioning immune defence is crucial for fitness, but our knowledge about the immune system and its complex interactions is still limited. Major histocompatibility complex (MHC) molecules are involved in T-cell mediated adaptive immune responses, but MHC is also highly upregulated during the initial innate immune response. The aim of our study was therefore to determine to what extent the highly polymorphic MHC is involved in interactions of the innate and adaptive immune defence and if specific functional MHC alleles (FA) or heterozygosity at the MHC are more important. METHODS: To do this we used captive house sparrows (Passer domesticus) to survey MHC diversity and immune function controlling for several environmental factors. MHC class I alleles were identified using parallel amplicon sequencing and to mirror immune function, several immunological tests that correspond to the innate and adaptive immunity were conducted. RESULTS: Our results reveal that MHC was linked to all immune tests, highlighting its importance for the immune defence. While all innate responses were associated with one single FA, adaptive responses (cell-mediated and humoral) were associated with several different alleles. DISCUSSION: We found that repeated injections of an antibody in nestlings and adults were linked to different FA and hence might affect different areas of the immune system. Also, individuals with a higher number of different FA produced a smaller secondary response, indicating a disadvantage of having numerous MHC alleles. These results demonstrate the complexity of the immune system in relation to the MHC and lay the foundation for other studies to further investigate this topic.
RESUMO
Sound propagates much faster and over larger distances in water than in air, mainly because of differences in the density of these media. This raises the question of whether terrestrial (land mammals, birds) and (semi-)aquatic animals (frogs, fishes, cetaceans) differ fundamentally in the way they communicate acoustically. Terrestrial vertebrates primarily produce sounds by vibrating vocal tissue (folds) directly in an airflow. This mechanism has been modified in frogs and cetaceans, whereas fishes generate sounds in quite different ways mainly by utilizing the swimbladder or pectoral fins. On land, vertebrates pick up sounds with light tympana, whereas other mechanisms have had to evolve underwater. Furthermore, fishes differ from all other vertebrates by not having an inner ear end organ devoted exclusively to hearing. Comparing acoustic communication within and between aquatic and terrestrial vertebrates reveals that there is no 'aquatic way' of sound communication, as compared with a more uniform terrestrial one. Birds and mammals display rich acoustic communication behaviour, which reflects their highly developed cognitive and social capabilities. In contrast, acoustic signaling seems to be the exception in fishes, and is obviously limited to short distances and to substrate-breeding species, whereas all cetaceans communicate acoustically and, because of their predominantly pelagic lifestyle, exploit the benefits of sound propagation in a dense, obstacle-free medium that provides fast and almost lossless signal transmission.
Assuntos
Ecossistema , Vertebrados/fisiologia , Vocalização Animal , Animais , Percepção Auditiva , AudiçãoRESUMO
BACKGROUND: Dendritic cells (DCs) are specialized first-line sensors of foreign materials invading the organism. These sentinel cells rely on pattern recognition receptors such as Nod-like or Toll-like receptors (TLRs) to launch immune reactions against pathogens, but also to mediate tolerance to self-antigens and, in the intestinal milieu, to nutrients and commensals. Since inappropriate DC activation contributes to inflammatory diseases and immunopathologies, a key question in the evaluation of orally ingested nanomaterials is whether their contact with DCs in the intestinal mucosa disrupts this delicate homeostatic balance between pathogen defense and tolerance. Here, we generated steady-state DCs by incubating hematopoietic progenitors with feline McDonough sarcoma-like tyrosine kinase 3 ligand (Flt3L) and used the resulting immature DCs to test potential biological responses against food-grade synthetic amorphous silica (SAS) representing a common nanomaterial generally thought to be safe. RESULTS: Interaction of immature and unprimed DCs with food-grade SAS particles and their internalization by endocytic uptake fails to elicit cytotoxicity and the release of interleukin (IL)-1α or tumor necrosis factor-α, which were identified as master regulators of acute inflammation in lung-related studies. However, the display of maturation markers on the cell surface shows that SAS particles activate completely immature DCs. Also, the endocytic uptake of SAS particles into these steady-state DCs leads to induction of the pro-IL-1ß precursor, subsequently cleaved by the inflammasome to secrete mature IL-1ß. In contrast, neither pro-IL-1ß induction nor mature IL-1ß secretion occurs upon internalization of TiO2 or FePO4 nanoparticles. The pro-IL-1ß induction is suppressed by pharmacologic inhibitors of endosomal TLR activation or by genetic ablation of MyD88, a downstream adapter of TLR pathways, indicating that endosomal pattern recognition is responsible for the observed cytokine response to food-grade SAS particles. CONCLUSIONS: Our results unexpectedly show that food-grade SAS particles are able to directly initiate the endosomal MyD88-dependent pathogen pattern recognition and signaling pathway in steady-state DCs. The ensuing activation of immature DCs with de novo induction of pro-IL-1ß implies that the currently massive use of SAS particles as food additive should be reconsidered.
Assuntos
Células Dendríticas/efeitos dos fármacos , Aditivos Alimentares/toxicidade , Interleucina-1beta/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Precursores de Proteínas/metabolismo , Dióxido de Silício/toxicidade , Animais , Células Cultivadas , Células Dendríticas/metabolismo , Células Dendríticas/ultraestrutura , Relação Dose-Resposta a Droga , Endocitose , Endossomos/efeitos dos fármacos , Endossomos/metabolismo , Endossomos/ultraestrutura , Aditivos Alimentares/síntese química , Aditivos Alimentares/metabolismo , Inocuidade dos Alimentos , Inflamassomos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/deficiência , Fator 88 de Diferenciação Mieloide/genética , Nanopartículas , Processamento de Proteína Pós-Traducional , Receptores de Reconhecimento de Padrão/metabolismo , Medição de Risco , Transdução de Sinais/efeitos dos fármacos , Dióxido de Silício/síntese química , Dióxido de Silício/metabolismo , Fatores de Tempo , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo , Regulação para CimaRESUMO
Nanotechnology offers new opportunities for providing health benefits in foods. Food fortification with iron phosphate nanoparticles (FePO4 NPs) is a promising new approach to reducing iron deficiency because FePO4 NPs combine high bioavailability with superior sensory performance in difficult to fortify foods. However, their safety remains largely untested. We fed rats for 90 days diets containing FePO4 NPs at doses at which iron sulfate (FeSO4), a commonly used food fortificant, has been shown to induce adverse effects. Feeding did not result in signs of toxicity, including oxidative stress, organ damage, excess iron accumulation in organs or histological changes. These safety data were corroborated by evidence that NPs were taken up by human gastrointestinal cell lines without reducing cell viability or inducing oxidative stress. Our findings suggest FePO4 NPs appear to be as safe for ingestion as FeSO4.
Assuntos
Compostos Férricos , Alimentos Fortificados , Nanopartículas , Estresse Oxidativo/efeitos dos fármacos , Animais , Disponibilidade Biológica , Sobrevivência Celular/efeitos dos fármacos , Dieta , Relação Dose-Resposta a Droga , Compostos Férricos/administração & dosagem , Compostos Férricos/efeitos adversos , Compostos Férricos/metabolismo , Glutationa/metabolismo , Células HT29 , Humanos , Sobrecarga de Ferro , Masculino , Nanopartículas/administração & dosagem , Nanopartículas/efeitos adversos , Nanopartículas/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
The development of nano-materials is viewed as one of the most important technological advances of the 21st century and new applications of nano-sized particles in the production, processing, packaging or storage of food are expected to emerge soon. This trend of growing commercialization of engineered nano-particles as part of modern diet will substantially increase oral exposure. Contrary to the proven benefits of nano-materials, however, possible adverse health effects have generally received less attention. This problem is very well illustrated by nano-structured synthetic amorphous silica (SAS), which is a common food additive since several decades although the relevant risk assessment has never been satisfactorily completed. A no observed adverse effect level of 2500 mg SAS particles/kg body weight per day was derived from the only available long-term administration study in rodents. However, extrapolation to a safe daily intake for humans is problematic due to limitations of this chronic animal study and knowledge gaps as to possible local intestinal effects of SAS particles, primarily on the gut-associated lymphoid system. This uncertainty is aggravated by digestion experiments indicating that dietary SAS particles preserve their nano-sized structure when reaching the intestinal lumen. An important aspect is whether food-borne particles like SAS alter the function of dendritic cells that, embedded in the intestinal mucosa, act as first-line sentinels of foreign materials. We conclude that nano-particles do not represent a completely new threat and that most potential risks can be assessed following procedures established for conventional chemical hazards. However, specific properties of food-borne nano-particles should be further examined and, for that purpose, in vitro tests with decision-making cells of the immune system are needed to complement existing in vivo studies.
Assuntos
Aditivos Alimentares/efeitos adversos , Nanoestruturas/efeitos adversos , Dióxido de Silício/efeitos adversos , Animais , Aditivos Alimentares/administração & dosagem , Aditivos Alimentares/química , Análise de Alimentos , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/metabolismo , Humanos , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Medição de Risco , Dióxido de Silício/administração & dosagem , Dióxido de Silício/químicaRESUMO
Diffuse large B-cell lymphoma (DLBCL) is a clinically heterogeneous lymphoid malignancy and the most common subtype of non-Hodgkin's lymphoma in adults, with one of the highest mortality rates in most developed areas of the world. More than half of DLBLC patients can be cured with standard R-CHOP regimens, however approximately 30 to 40 % of patients will develop relapsed/refractory disease that remains a major cause of morbidity and mortality due to the limited therapeutic options.Recent advances in gene expression profiling have led to the identification of at least three distinct molecular subtypes of DLBCL: a germinal center B cell-like subtype, an activated B cell-like subtype, and a primary mediastinal B-cell lymphoma subtype. Moreover, recent findings have not only increased our understanding of the molecular basis of chemotherapy resistance but have also helped identify molecular subsets of DLBCL and rational targets for drug interventions that may allow for subtype/subset-specific molecularly targeted precision medicine and personalized combinations to both prevent and treat relapsed/refractory DLBCL. Novel agents such as lenalidomide, ibrutinib, bortezomib, CC-122, epratuzumab or pidilizumab used as single-agent or in combination with (rituximab-based) chemotherapy have already demonstrated promising activity in patients with relapsed/refractory DLBCL. Several novel potential drug targets have been recently identified such as the BET bromodomain protein (BRD)-4, phosphoribosyl-pyrophosphate synthetase (PRPS)-2, macrodomain-containing mono-ADP-ribosyltransferase (ARTD)-9 (also known as PARP9), deltex-3-like E3 ubiquitin ligase (DTX3L) (also known as BBAP), NF-kappaB inducing kinase (NIK) and transforming growth factor beta receptor (TGFßR).This review highlights the new insights into the molecular basis of relapsed/refractory DLBCL and summarizes the most promising drug targets and experimental treatments for relapsed/refractory DLBCL, including the use of novel agents such as lenalidomide, ibrutinib, bortezomib, pidilizumab, epratuzumab, brentuximab-vedotin or CAR T cells, dual inhibitors, as well as mechanism-based combinatorial experimental therapies. We also provide a comprehensive and updated list of current drugs, drug targets and preclinical and clinical experimental studies in DLBCL. A special focus is given on STAT1, ARTD9, DTX3L and ARTD8 (also known as PARP14) as novel potential drug targets in distinct molecular subsets of DLBCL.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Resistencia a Medicamentos Antineoplásicos , Humanos , Imunoterapia , Linfoma Difuso de Grandes Células B/patologia , Terapia de Alvo Molecular , Medicina de PrecisãoRESUMO
BACKGROUND: Prostate cancer (PCa) is one of the leading causes of cancer-related mortality and morbidity in the aging male population and represents the most frequently diagnosed malignancy in men around the world. The Deltex (DTX)-3-like E3 ubiquitin ligase (DTX3L), also known as B-lymphoma and BAL-associated protein (BBAP), was originally identified as a binding partner of the diphtheria-toxin-like macrodomain containing ADP-ribosyltransferase-9 (ARTD9), also known as BAL1 and PARP9. We have previously demonstrated that ARTD9 acts as a novel oncogenic survival factor in high-risk, chemo-resistant, diffuse large B cell lymphoma (DLBCL). The mono-ADP-ribosyltransferase ARTD8, also known as PARP14 functions as a STAT6-specific co-regulator of IL4-mediated proliferation and survival in B cells. METHODS: Co-expression of DTX3L, ARTD8, ARTD9 and STAT1 was analyzed in the metastatic PCa (mPCa) cell lines PC3, DU145, LNCaP and in the normal prostate luminal epithelial cell lines HPE and RWPE1. Effects on cell proliferation, survival and cell migration were determined in PC3, DU145 and/or LNCaP cells depleted of DTX3L, ARTD8, ARTD9, STAT1 and/or IRF1 compared to their proficient control cells, respectively. In further experiments, real-time RT-PCR, Western blot, immunofluorescence and co-immunoprecipitations were conducted to evaluate the physical and functional interactions between DTX3L, ARTD8 and ARTD9. RESULTS: Here we could identify DTX3L, ARTD9 and ARTD8 as novel oncogenic survival factors in mPCa cells. Our studies revealed that DTX3L forms a complex with ARTD8 and mediates together with ARTD8 and ARTD9 proliferation, chemo-resistance and survival of mPCa cells. In addition, DTX3L, ARTD8 and ARTD9 form complexes with each other. Our study provides first evidence that the enzymatic activity of ARTD8 is required for survival of mPCa cells. DTX3L and ARTD9 act together as repressors of the tumor suppressor IRF1 in mPCa cells. Furthermore, the present study shows that DTX3L together with STAT1 and STAT3 is implicated in cell migration of mPCa cells. CONCLUSIONS: Our data strongly indicate that a crosstalk between STAT1, DTX3L and ARTD-like mono-ADP-ribosyltransferases mediates proliferation and survival of mPCa cells. The present study further suggests that the combined targeted inhibition of STAT1, ARTD8, ARTD9 and/or DTX3L could increase the efficacy of chemotherapy or radiation treatment in prostate and other high-risk tumor types with an increased STAT1 signaling.
Assuntos
Fator Regulador 1 de Interferon/genética , Proteínas de Neoplasias/genética , Poli(ADP-Ribose) Polimerases/genética , Neoplasias da Próstata/genética , Ubiquitina-Proteína Ligases/genética , Movimento Celular/genética , Proliferação de Células , Humanos , Fator Regulador 1 de Interferon/metabolismo , Masculino , Metástase Neoplásica , Proteínas de Neoplasias/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Neoplasias da Próstata/patologia , Fator de Transcrição STAT1/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
PURPOSE: Our aim was to investigate whether microRNAs can predict the clinical outcome of patients with gastric cancer. We used integrated analysis of microRNA and mRNA expression profiles to identify gastric cancer microRNA subtypes and their underlying regulatory scenarios. EXPERIMENTAL DESIGN: MicroRNA-based gastric cancer subtypes were identified by consensus clustering analysis of microRNA profiles of 90 gastric cancer tissues. Activated pathways in the subtypes were identified by gene expression profiles. Further integrated analysis was conducted to model a microRNA regulatory network for each subtype. RNA and protein expression were analyzed by RT-PCR and tissue microarray, respectively, in a cohort of 385 gastric cancer cases (including the 90 cases for profiling) to validate the key microRNAs and targets in the network. Both in vitro and in vivo experiments were carried out to further validate the findings. RESULTS: MicroRNA profiles of 90 gastric cancer cases identified two microRNA subtypes significantly associated with survival. The poor-prognosis gastric cancer microRNA subtype was characterized by overexpression of epithelial-to-mesenchymal transition (EMT) markers. This gastric cancer "mesenchymal subtype" was further validated in a patient cohort comprising 385 cases. Integrated analysis identified a key microRNA regulatory network likely driving the gastric cancer mesenchymal subtype. Three of the microRNAs (miR-200c, miR-200b, and miR-125b) targeting the most genes in the network were significantly associated with survival. Functional experiments demonstrated that miR-200b suppressed ZEB1, augmented E-cadherin, inhibited cell migration, and suppressed tumor growth in a mouse model. CONCLUSIONS: We have uncovered a key microRNA regulatory network that defines the mesenchymal gastric cancer subtype significantly associated with poor overall survival in gastric cancer.
Assuntos
MicroRNAs/genética , Neoplasias Gástricas/genética , Idoso , Animais , Antígenos CD , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Feminino , Redes Reguladoras de Genes , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Estimativa de Kaplan-Meier , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Transplante de Neoplasias , Fenótipo , Prognóstico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidade , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma , Homeobox 1 de Ligação a E-box em Dedo de ZincoRESUMO
ADP-ribosylation is an important post-translational protein modification (PTM) that regulates diverse biological processes. ADP-ribosyltransferase diphtheria toxin-like 10 (ARTD10, also known as PARP10) mono-ADP-ribosylates acidic side chains and is one of eighteen ADP-ribosyltransferases that catalyze mono- or poly-ADP-ribosylation of target proteins. Currently, no enzyme is known that reverses ARTD10-catalyzed mono-ADP-ribosylation. Here we report that ARTD10-modified targets are substrates for the macrodomain proteins MacroD1, MacroD2 and C6orf130 from Homo sapiens as well as for the macrodomain protein Af1521 from archaebacteria. Structural modeling and mutagenesis of MacroD1 and MacroD2 revealed a common core structure with Asp102 and His106 of MacroD2 implicated in the hydrolytic reaction. Notably, MacroD2 reversed the ARTD10-catalyzed, mono-ADP-ribose-mediated inhibition of glycogen synthase kinase 3ß (GSK3ß) in vitro and in cells, thus underlining the physiological and regulatory importance of mono-ADP-ribosylhydrolase activity. Our results establish macrodomain-containing proteins as mono-ADP-ribosylhydrolases and define a class of enzymes that renders mono-ADP-ribosylation a reversible modification.
Assuntos
N-Glicosil Hidrolases/metabolismo , Adenosina Difosfato Ribose/metabolismo , Humanos , Modelos Moleculares , Mutagênese , N-Glicosil Hidrolases/química , N-Glicosil Hidrolases/genéticaRESUMO
The B-aggressive lymphoma-1 protein and ADP-ribosyltransferase BAL1/ARTD9 has been recently identified as a risk-related gene product in aggressive diffuse large B-cell lymphoma (DLBCL). BAL1 is constitutively expressed in a subset of high-risk DLBCLs with an active host inflammatory response and has been suggested to be associated with interferon-related gene expression. Here we identify BAL1 as a novel oncogenic survival factor in DLBCL and show that constitutive overexpression of BAL1 in DLBCL tightly associates with intrinsic interferon-gamma (IFNγ) signaling and constitutive activity of signal transducer and activator of transcription (STAT)-1. Remarkably, BAL1 stimulates the phosphorylation of both STAT1 isoforms, STAT1α and STAT1ß, on Y701 and thereby promotes the nuclear accumulation of the antagonistically acting and transcriptionally repressive isoform STAT1ß. Moreover, BAL1 physically interacts with both STAT1α and STAT1ß through its macrodomains in an ADP-ribosylation-dependent manner. BAL1 directly inhibits, together with STAT1ß, the expression of tumor suppressor and interferon response factor (IRF)-1. Conversely, BAL1 enhances the expression of the proto-oncogenes IRF2 and B-cell CLL/lymphoma (BCL)-6 in DLBCL. Our results show for the first time that BAL1 represses the anti-proliferative and pro-apoptotic IFNγ-STAT1-IRF1-p53 axis and mediates proliferation, survival and chemo-resistance in DLBCL. As a consequence constitutive IFNγ-STAT1 signaling does not lead to apoptosis but rather to chemo-resistance in DLBCL overexpressing BAL1. Our results suggest that BAL1 may induce an switch in STAT1 from a tumor suppressor to an oncogene in high-risk DLBCL.
Assuntos
Apoptose , Proliferação de Células , Fator Regulador 1 de Interferon/metabolismo , Interferon gama/metabolismo , Linfoma Difuso de Grandes Células B/metabolismo , Proteínas de Neoplasias/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/genética , Células HEK293 , Humanos , Fator Regulador 1 de Interferon/genética , Fator Regulador 2 de Interferon/biossíntese , Fator Regulador 2 de Interferon/genética , Interferon gama/genética , Linfoma Difuso de Grandes Células B/genética , Proteínas de Neoplasias/genética , Poli(ADP-Ribose) Polimerases , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Fator de Transcrição STAT1/genética , Proteína Supressora de Tumor p53/genéticaRESUMO
Environments undergo short-term and long-term changes due to natural or human-induced events. Animals differ in their ability to cope with such changes which can be related to their ecology. Changes in the environment often elicit avoidance reactions (neophobia) which protect animals from dangerous situations but can also inhibit exploration and familiarization with novel situations and thus, learning about new resources. Studies investigating the relationship between a species' ecology and its neophobia have so far been restricted to comparing only a few species and mainly in captivity. The current study investigated neophobia reactions to experimentally-induced changes in the natural environment of six closely-related blackbird species (Icteridae), including two species represented by two distinct populations. For analyses, neophobic reactions (difference in number of birds feeding and time spent feeding with and without novel objects) were related to several measures of ecological plasticity and the migratory strategy (resident or migratory) of the population. Phylogenetic relationships were incorporated into the analysis. The degree of neophobia was related to migratory strategy with migrants expressing much higher neophobia (fewer birds feeding and for a shorter time with objects present) than residents. Furthermore, neophobia showed a relationship to diet breadth with fewer individuals of diet generalists than specialists returning when objects were present supporting the dangerous niche hypothesis. Residents may have evolved lower neophobia as costs of missing out on opportunities may be higher for residents than migrants as the former are restricted to a smaller area. Lower neophobia allows them approaching changes in the environment (e.g. novel objects) quickly, thereby securing access to resources. Additionally, residents have a greater familiarity with similar situations in the area than migrants and the latter may, therefore, initially stay behind resident species.
Assuntos
Migração Animal/fisiologia , Aprendizagem da Esquiva/fisiologia , Filogenia , Aves Canoras/fisiologia , Animais , California , Comportamento Exploratório/fisiologia , Geografia , Humanos , Mississippi , Especificidade da EspécieRESUMO
AIM: To investigate the role of neurotensin (NTS) in hepatocellular carcinoma (HCC) sub- grouping and the clinical and pathological significance of activation of NTS/IL-8 pathway in HCC. METHODS: The genome-wide gene expression profiling were conducted in 10 pairs of cancer tissues and corresponding normal adjacent tissues samples using Affymetrix GeneChip® Human Genome U133 Plus 2.0 microarray to screen differentially expressing genes and enrich dysfunctional activated pathways among different HCC subgroups. The levels of NTS protein and multiple inflammation and epithelial mesenchymal transition (EMT) related proteins, including IL-8, VEGF, MMP9, CD68, E-Cadherin, ß-Catenin and Vimentin were examined in 64 cases of paraffin-embedded HCC samples using immunohistochemistry (IHC) staining method. The clinical outcome and overall survival (OS) were compared. RESULTS: A subgroup of HCC characterized by up-regulated NTS expression was accompanied by up-regulated inflammatory responses and EMT. The direct interaction between NTS and IL-8 was identified by pathway enrichment analysis. Significantly increased IL-8 protein was confirmed in 90.91% of NTS(+) HCC samples and significantly positively correlated to the levels of NTS protein in cancer tissues (Pâ=â0.036), which implied activation of NTS/IL-8 pathway in HCC. The levels of VEGF and MMP9 correlated with co-expression of NTS and IL-8. Increased infiltration of CD68(+) macrophages and more cancer cells displaying EMT features were found in NTS(+)IL-8(+) samples. The co-expression of NTS and IL-8 in cancer significantly correlated with the clinical outcomes, as the mortality rate of NTS(+)IL-8(+) HCC patients is 2.5-fold higher than the others after the surgery (Pâ=â0.022). Accordingly, the OS of NTS(+)IL-8(+) HCC patients significantly decreased who are under a higher hazard of death at an expected hazard ratio (HR) of 3.457. CONCLUSION: Dysfunctional activation of the NTS/IL-8 pathway was detected in HCC which is associated with increased inflammatory response in microenvironment, enhanced EMT in cancer, and worse prognosis in HCC patients.
Assuntos
Carcinoma Hepatocelular/genética , Transição Epitelial-Mesenquimal/genética , Interleucina-8/genética , Neoplasias Hepáticas/genética , Neurotensina/genética , Microambiente Tumoral/genética , Adulto , Idoso , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/cirurgia , Análise por Conglomerados , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Imuno-Histoquímica , Interleucina-8/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Neurotensina/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Transdução de Sinais/genética , Análise de SobrevidaRESUMO
Trochulus oreinos oreinos and T. oreinos scheerpeltzi are two land snail taxa endemic to the Northeastern Austrian Alps, which have been regarded as subspecies of the highly variable, widespread land snail T. hispidus. We analysed these three taxa morphologically and genetically to evaluate whether a delimitation between them is possible and, if so, to resolve their phylogenetic relationships. Shell morphological results revealed high similarity between the two T. oreinos taxa, and that they are clearly separated from T. hispidus. Additionally, the T. oreinos subspecies concur with respect to their habitat preferences, as they are both restricted to rocky high alpine areas, whereas the local form of T. hispidus is distributed over a wider altitudinal range in moist areas and scrubby perennial herb vegetation near water bodies. While the morphological and ecological results allow clear differentiation between T. hispidus and T. oreinos only, analyses of the mitochondrial cytochrome c oxidase subunit I and 16S rRNA genes revealed high sequence divergences between all three taxa, which indicates that they represent old lineages. The two T. oreinos taxa appear as distantly related sister groups, well separated from T. hispidus. Whether T. o. oreinos and T. o. scheerpeltzi should be considered as species cannot be decided at the current state of knowledge.
RESUMO
Five antiepidermal growth factor receptor therapies have been approved for the treatment of solid tumors. However, response rates are relatively low. Several biomarkers that enrich for patients with tumors most likely to respond to these therapeutic agents have been identified. Mutations in the intermediate signal transduction pathway member KRAS also selects patients with tumors depending on signaling through this pathway. However, because KRAS acts downstream of the EGF receptor, somatic changes in this gene can be used as a marker to exclude patients unlikely to benefit from anti-EGFR therapy. Recent clinical data have provided substantial evidence that KRAS mutational status should be utilized as a diagnostic marker for predicting that response to anti-EGFR therapies in colorectal and non-small cell lung cancer.
Assuntos
Antineoplásicos/farmacologia , Receptores ErbB/antagonistas & inibidores , Mutação , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Animais , Progressão da Doença , Frequência do Gene , Humanos , Proteínas Proto-Oncogênicas p21(ras) , SobrevidaRESUMO
Usutu virus (USUV), family Flaviviridae, has been responsible for avian mortality in Austria from 2001 to 2006. The proportion of USUV-positive individuals among the investigated dead birds decreased dramatically after 2004. To test the hypothesis that establishment of herd immunity might be responsible, serological examinations of susceptible wild birds were performed. Blood samples of 442 wild birds of 55 species were collected in 4 consecutive years (2003--2006). In addition, 86 individuals from a birds of prey rehabilitation centre were bled before, at the peak, and after the 2005 USUV transmission season in order to identify titre dynamics and seroconversions. The haemagglutination inhibition test was used for screening and the plaque reduction neutralization test for confirmation. While in the years 2003 and 2004 the proportion of seropositive wild birds was <10%, the percentage of seroreactors raised to >50% in 2005 and 2006. At the birds of prey centre, almost three quarters of the owls and raptors exhibited antibodies before the 2005 transmission season; this percentage dropped to less than half at the peak of USUV transmission and raised again to almost two thirds after the transmission season. These data show a from year to year continuously increasing proportion of seropositive wild birds. The owl and raptor data indicate significant viral exposure in the previous season(s), but also a number of new infections during the current season, despite the presence of antibodies in some of these birds. Herd immunity is a possible explanation for the significant decrease in USUV-associated bird mortalities in Austria during the recent years.