RESUMO
OBJECTIVE: Catecholaminergic signaling has been a target for therapy in different type of cancers. In this work, we characterized the ADRß2, DRD1 and DRD2 expression in healthy tissue and endometrial tumors to evaluate their prognostic significance in endometrial cancer (EC), unraveling their possible application as an antitumor therapy. METHODS: 109 EC patients were included. The expression of the ADRß2, DRD1 and DRD2 proteins was evaluated by immunohistochemistry and univariate and multivariate analysis to assess their association with clinic-pathological and outcome variables. Finally, HEC1A and AN3CA EC cell lines were exposed to different concentrations of selective dopaminergic agents alone or in combination to study their effects on cellular viability. RESULTS: ADRß2 protein expression was not associated with clinico-pathological parameters or prognosis. DRD1 protein expression was reduced in tumors samples but showed a significant inverse association with tumor size and stage. DRD2 protein expression was significantly associated with non-endometrioid EC, high grade tumors, tumor size, worse disease-free survival (HR = 3.47 (95%CI:1.35-8.88)) and overall survival (HR = 2.98 (95%CI:1.40-6.34)). The DRD1 agonist fenoldopam showed a reduction of cellular viability in HEC1A and AN3CA cells. The exposure to domperidone, a DRD2 antagonist, significantly reduced cell viability compared to the control. Finally, DRD1 agonism and DRD2 antagonism combination induced a significant reduction in cell viability of the AN3CA cells compared to monotherapy, close to being an additive response than a synergistic effect (CI of 1.1 at 0.5% Fa). CONCLUSION: DRD1 and DRD2 expression levels showed a significant association with clinico-pathological parameters. Both the combined activation of DRD1 and blockage of DRD2 may form an innovative strategy to inhibit tumor growth in EC.
Assuntos
Neoplasias do Endométrio , Receptores de Dopamina D2 , Feminino , Humanos , Prognóstico , Receptores de Dopamina D2/metabolismo , Neoplasias do Endométrio/tratamento farmacológicoRESUMO
Vaults are protein nanoparticles that are found in almost all eukaryotic cells but are absent in prokaryotic ones. Due to their properties (nanometric size, biodegradability, biocompatibility, and lack of immunogenicity), vaults show enormous potential as a bio-inspired, self-assembled drug-delivery system (DDS). Vault architecture is directed by self-assembly of the "major vault protein" (MVP), the main component of this nanoparticle. Recombinant expression (in different eukaryotic systems) of the MVP resulted in the formation of nanoparticles that were indistinguishable from native vaults. Nowadays, recombinant vaults for different applications are routinely produced in insect cells and purified by successive ultracentrifugations, which are both tedious and time-consuming strategies. To offer cost-efficient and faster protocols for nanoparticle production, we propose the production of vault-like nanoparticles in Escherichia coli cells, which are still one of the most widely used prokaryotic cell factories for recombinant protein production. The strategy proposed allowed for the spontaneous encapsulation of the engineered cargo protein within the self-assembled vault-like nanoparticles by simply mixing the clarified lysates of the producing cells. Combined with well-established affinity chromatography purification methods, our approach contains faster, cost-efficient procedures for biofabrication in a well-known microbial cell factory and the purification of "ready-to-use" loaded protein nanoparticles, thereby opening the way to faster and easier engineering and production of vault-based DDSs.
Assuntos
Escherichia coli , Nanopartículas , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/metabolismo , Sistemas de Liberação de Medicamentos , Nanopartículas/químicaRESUMO
Silica/biopolymer hydrogel-based materials constitute very attractive platforms for various emerging biomedical applications, particularly for bone repair. The incorporation of calcium phosphates in the hybrid network allows for designing implants with interesting biological properties. Here, we introduce a synthesis procedure for obtaining silica-chitosan (CS)-tricalcium phosphate (TCP) xerogels, with CS nominal content varying from 4 to 40 wt.% and 10 to 20 wt.% TCP. Samples were obtained using the sol-gel process assisted with ultrasound probe, and the influence of ethanol or water as washing solvents on surface area, micro- and mesopore volume, and average pore size were examined in order to optimize their textural properties. Three washing solutions with different soaking conditions were tested: 1 or 7 days in absolute ethanol and 30 days in distilled water, resulting in E1, E7, and W30 washing series, respectively. Soaked samples were eventually dried by evaporative drying at air ambient pressure, and the formation of interpenetrated hybrid structures was suggested by Fourier transformed infrared (FTIR) spectroscopy. In addition the impact that both washing solvent and TCP content have on the biodegradation, in vitro bioactivity and osteoconduction of xerogels were explored. It was found that calcium and phosphate-containing ethanol-washed xerogels presented in vitro release of calcium (2-12 mg/L) and silicon ions (~60-75 mg/L) after one week of soaking in phosphate-buffered saline (PBS), as revealed by inductive coupled plasma (ICP) spectroscopy analysis. However, only the release of silicon was detected for water-washed samples. Besides, all the samples exhibited in vitro bioactivity in simulated body fluid (SBF), as well as enhanced in vitro cell growth and also significant focal adhesion development and maturation.
Assuntos
Regeneração Óssea , Fosfatos de Cálcio/química , Quitosana/química , Géis/química , Osteoblastos/citologia , Dióxido de Silício/química , Solventes/química , Materiais Biocompatíveis/química , Líquidos Corporais , Células Cultivadas , Humanos , Teste de MateriaisRESUMO
One-third of diffuse large B-cell lymphoma patients are refractory to initial treatment or relapse after rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone chemotherapy. In these patients, CXCR4 overexpression (CXCR4+) associates with lower overall and disease-free survival. Nanomedicine pursues active targeting to selectively deliver antitumor agents to cancer cells; a novel approach that promises to revolutionize therapy by dramatically increasing drug concentration in target tumor cells. In this study, we intravenously administered a liganded protein nanocarrier (T22-GFP-H6) targeting CXCR4+ lymphoma cells in mouse models to assess its selectivity as a nanocarrier by measuring its tissue biodistribution in cancer and normal cells. No previous protein-based nanocarrier has been described as specifically targeting lymphoma cells. T22-GFP-H6 achieved a highly selective tumor uptake in a CXCR4+ lymphoma subcutaneous model, as detected by fluorescent emission. We demonstrated that tumor uptake was CXCR4-dependent because pretreatment with AMD3100, a CXCR4 antagonist, significantly reduced tumor uptake. Moreover, in contrast to CXCR4+ subcutaneous models, CXCR4- tumors did not accumulate the nanocarrier. Most importantly, after intravenous injection in a disseminated model, the nanocarrier accumulated and internalized in all clinically relevant organs affected by lymphoma cells with negligible distribution to unaffected tissues. Finally, we obtained antitumor effect without toxicity in a CXCR4+ lymphoma model by administration of T22-DITOX-H6, a nanoparticle incorporating a toxin with the same structure as the nanocarrier. Hence, the use of the T22-GFP-H6 nanocarrier could be a good strategy to load and deliver drugs or toxins to treat specifically CXCR4-mediated refractory or relapsed diffuse large B-cell lymphoma without systemic toxicity.
Assuntos
Antineoplásicos , Linfoma Difuso de Grandes Células B , Animais , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Camundongos , Recidiva Local de Neoplasia/tratamento farmacológico , Prednisona/uso terapêutico , Receptores CXCR4/genética , Rituximab/uso terapêutico , Transdução de Sinais , Distribuição Tecidual , Vincristina/uso terapêuticoRESUMO
Reactive astrogliosis, a complex process characterized by cell hypertrophy and upregulation of components of intermediate filaments, is a common feature in brains of Alzheimer's patients. Reactive astrocytes are found in close association with neuritic plaques; however, the precise role of these glial cells in disease pathogenesis is unknown. In this study, using immunohistochemical techniques and light and electron microscopy, we report that plaque-associated reactive astrocytes enwrap, engulf and may digest presynaptic dystrophies in the hippocampus of amyloid precursor protein/presenilin-1 (APP/PS1) mice. Microglia, the brain phagocytic population, was apparently not engaged in this clearance. Phagocytic reactive astrocytes were present in 35% and 67% of amyloid plaques at 6 and 12 months of age, respectively. The proportion of engulfed dystrophic neurites was low, around 7% of total dystrophies around plaques at both ages. This fact, along with the accumulation of dystrophic neurites during disease course, suggests that the efficiency of the astrocyte phagocytic process might be limited or impaired. Reactive astrocytes surrounding and engulfing dystrophic neurites were also detected in the hippocampus of Alzheimer's patients by confocal and ultrastructural analysis. We posit that the phagocytic activity of reactive astrocytes might contribute to clear dysfunctional synapses or synaptic debris, thereby restoring impaired neural circuits and reducing the inflammatory impact of damaged neuronal parts and/or limiting the amyloid pathology. Therefore, potentiation of the phagocytic properties of reactive astrocytes may represent a potential therapy in Alzheimer's disease.
Assuntos
Doença de Alzheimer/metabolismo , Astrócitos/metabolismo , Fagocitose/fisiologia , Sinapses/metabolismo , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Astrócitos/patologia , Modelos Animais de Doenças , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/metabolismo , Microglia/patologia , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Presenilina-1/genética , Presenilina-1/metabolismo , Sinapses/patologiaRESUMO
Bacterial inclusion bodies are non-toxic, mechanically stable and functional protein amyloids within the nanoscale size range that are able to naturally penetrate into mammalian cells, where they deliver the embedded protein in a functional form. The potential use of inclusion bodies in protein delivery or protein replacement therapies is strongly impaired by the absence of specificity in cell binding and penetration, thus preventing targeting. To address this issue, we have here explored whether the genetic fusion of two tumor-homing peptides, the CXCR4 ligands R9 and T22, to an inclusion body-forming green fluorescent protein (GFP), would keep the interaction potential and the functionality of the fused peptides and then confer CXCR4 specificity in cell binding and further uptake of the materials. The fusion proteins have been well produced in Escherichia coli in their full-length form, keeping the potential for fluorescence emission of the partner GFP. By using specific inhibitors of CXCR4 binding, we have demonstrated that the engineered protein particles are able to penetrate CXCR4+ cells, in a receptor-mediated way, without toxicity or visible cytopathic effects, proving the availability of the peptide ligands on the surface of inclusion bodies. Since no further modification is required upon their purification, the biological production of genetically targeted inclusion bodies opens a plethora of cost-effective possibilities in the tissue-specific intracellular transfer of functional proteins through the use of structurally and functionally tailored soft materials.
Assuntos
Amiloide/administração & dosagem , Amiloide/química , Corpos de Inclusão/química , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Neoplasias/tratamento farmacológico , Amiloide/metabolismo , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Escherichia coli/metabolismo , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Corpos de Inclusão/metabolismo , Peptídeos/administração & dosagem , Peptídeos/química , Peptídeos/metabolismo , Receptores CXCR4/administração & dosagem , Receptores CXCR4/química , Receptores CXCR4/metabolismo , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismoRESUMO
Although all KRas (protein that in humans is encoded by the KRas gene) point mutants are considered to have a similar prognostic capacity, their transformation and tumorigenic capacities vary widely. We compared the metastatic efficiency of KRas G12V (Kirsten rat sarcoma viral oncogene homolog with valine mutation at codon 12) and KRas G13D (Kirsten rat sarcoma viral oncogene homolog with aspartic mutation at codon 13) oncogenes in an orthotopic colorectal cancer (CRC) model. Following subcutaneous preconditioning, recombinant clones of the SW48 CRC cell line [Kras wild-type (Kras WT)] expressing the KRas G12V or KRas G13D allele were microinjected in the mouse cecum. The percentage of animals developing lymph node metastasis was higher in KRas G12V than in KRas G13D mice. Microscopic, macroscopic, and visible lymphatic foci were 1.5- to 3.0-fold larger in KRas G12V than in KRas G13D mice (P < 0.05). In the lung, only microfoci were developed in both groups. KRas G12V primary tumors had lower apoptosis (7.0 ± 1.2 vs. 7.4 ± 1.0 per field, P = 0.02), higher tumor budding at the invasion front (1.2 ± 0.2 vs. 0.6 ± 0.1, P = 0.04), and a higher percentage of C-X-C chemokine receptor type 4 (CXCR4)-overexpressing intravasated tumor emboli (49.8 ± 9.4% vs. 12.8 ± 4.4%, P < 0.001) than KRas G13D tumors. KRas G12V primary tumors showed Akt activation, and ß5 integrin, vascular endothelial growth factor A (VEGFA), and Serpine-1 overexpression, whereas KRas G13D tumors showed integrin ß1 and angiopoietin 2 (Angpt2) overexpression. The increased cell survival, invasion, intravasation, and specific molecular regulation observed in KRas G12V tumors is consistent with the higher aggressiveness observed in patients with CRC expressing this oncogene.
Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Angiopoietina-2/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Humanos , Integrina beta1/metabolismo , Metástase Linfática , Camundongos , Camundongos Nus , Mutação , Invasividade Neoplásica , Metástase Neoplásica , Proteínas de Ligação a RNA/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
BACKGROUND: Production of recombinant drugs in process-friendly endotoxin-free bacterial factories targets to a lessened complexity of the purification process combined with minimized biological hazards during product application. The development of nanostructured recombinant materials in innovative nanomedical activities expands such a need beyond plain functional polypeptides to complex protein assemblies. While Escherichia coli has been recently modified for the production of endotoxin-free proteins, no data has been so far recorded regarding how the system performs in the fabrication of smart nanostructured materials. RESULTS: We have here explored the nanoarchitecture and in vitro and in vivo functionalities of CXCR4-targeted, self-assembling protein nanoparticles intended for intracellular delivery of drugs and imaging agents in colorectal cancer. Interestingly, endotoxin-free materials exhibit a distinguishable architecture and altered size and target cell penetrability than counterparts produced in conventional E. coli strains. These variant nanoparticles show an eventual proper biodistribution and highly specific and exclusive accumulation in tumor upon administration in colorectal cancer mice models, indicating a convenient display and function of the tumor homing peptides and high particle stability under physiological conditions. DISCUSSION: The observations made here support the emerging endotoxin-free E. coli system as a robust protein material producer but are also indicative of a particular conformational status and organization of either building blocks or oligomers. This appears to be promoted by multifactorial stress-inducing conditions upon engineering of the E. coli cell envelope, which impacts on the protein quality control of the cell factory.
Assuntos
Escherichia coli/metabolismo , Nanopartículas , Multimerização Proteica , Proteínas/química , Proteínas/metabolismo , Animais , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Células HeLa , Humanos , Camundongos , Camundongos Nus , Nanopartículas/química , Nanopartículas/metabolismo , Tamanho da Partícula , Polimerização , Engenharia de Proteínas/métodos , Proteínas/farmacologia , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Relação Estrutura-AtividadeRESUMO
The chemokine receptor CXCR4 has been implicated in the migration and trafficking of malignant B cells in several haematological malignancies. Over-expression of CXCR4 has been identified in haematological tumours, but data concerning the role of this receptor in diffuse large B cell lymphoma (DLBCL) are lacking. CXCR4 is a marker of poor prognosis in various neoplasms, correlating with metastatic disease and decreased survival of patients. We studied CXCR4 involvement in cell migration in vitro and dissemination in vivo. We also evaluated the prognostic significance of CXCR4 in 94 biopsies of DLBCL patients. We observed that the level of expression of CXCR4 in DLBCL cell lines correlated positively with in vitro migration. Expression of the receptor was also associated with increased engraftment and dissemination, and decreased survival time in NOD/SCID mice. Furthermore, administration of a specific CXCR4 antagonist, AMD3100, decreased dissemination of DLBCL cells in a xenograft mouse model. In addition, we found that CXCR4 expression is an independent prognostic factor for shorter overall survival and progression-free survival in DLBCL patients. These results show that CXCR4 mediates dissemination of DLBCL cells and define for the first time its value as an independent prognostic marker in DLBCL patients.
Assuntos
Movimento Celular/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/fisiopatologia , Receptores CXCR4/fisiologia , Animais , Benzilaminas , Linhagem Celular Tumoral , Ciclamos , Modelos Animais de Doenças , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Compostos Heterocíclicos/farmacologia , Humanos , Técnicas In Vitro , Linfoma Difuso de Grandes Células B/patologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Invasividade Neoplásica/fisiopatologia , Prognóstico , Receptores CXCR4/antagonistas & inibidores , Receptores CXCR4/genética , Taxa de Sobrevida , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Unliganded drug-nanoconjugates accumulate passively in the tumor whereas liganded nanoconjugates promote drug internalization in tumor cells via endocytosis and increase antitumor efficacy. Whether or not tumor cell internalization associates with enhanced tumor uptake is still under debate. We here compared tumor uptake of T22-GFP-H6, a liganded protein carrier targeting the CXCR4 receptor, and the unliganded GFP-H6 carrier in subcutaneous and metastatic colorectal cancer models. T22-GFP-H6 had a higher tumor uptake in primary tumor and metastatic foci than GFP-H6, with no biodistribution or toxicity on normal tissues. T22-GFP-H6 was detected in target CXCR4+ tumor cell cytosol whereas GFP-H6 was detected in tumor stroma. SDF1-α co-administration switched T22-GFP-H6 internalization from CXCR4+ tumor epithelial cells to the stroma. Therefore, the incorporation of a targeting ligand promotes selective accumulation of the nanocarrier inside target tumor cells while increasing whole tumor uptake in a CXCR4-dependent manner, validating T22-GFP-H6 as a CXCR4-targeted drug carrier.
Assuntos
Neoplasias Colorretais/tratamento farmacológico , Receptores CXCR4 , Portadores de Fármacos , Endocitose , Humanos , Ligantes , Nanotecnologia , Peptídeos , Transdução de Sinais , Distribuição TecidualRESUMO
A single chain polypeptide containing the low density lipoprotein receptor (LDLR) ligand Seq-1 with blood-brain barrier (BBB) crossing activity has been successfully modified by conventional genetic engineering to self-assemble into stable protein-only nanoparticles of 30nm. The nanoparticulate presentation dramatically enhances in vitro, LDLR-dependent cell penetrability compared to the parental monomeric version, but the assembled protein does not show any enhanced brain targeting upon systemic administration. While the presentation of protein drugs in form of nanoparticles is in general advantageous regarding correct biodistribution, this principle might not apply to brain targeting that is hampered by particular bio-physical barriers. Irrespective of this fact, which is highly relevant to the nanomedicine of central nervous system, engineering the cationic character of defined protein stretches is revealed here as a promising and generic approach to promote the controlled oligomerization of biologically active protein species as still functional, regular nanoparticles.
Assuntos
Barreira Hematoencefálica , Sistemas de Liberação de Medicamentos , Nanopartículas , Peptídeos , Humanos , Receptores de LDL , Distribuição TecidualRESUMO
Sprint speed has a capital relevance in most animals' fitness, mainly for fleeing from predators. Sprint performance is maximal within a certain range of body temperatures in ectotherms, whose thermal upkeep relies on exogenous thermal sources. Ectotherms can respond to diverse thermal environments either by shifting their thermal preferences or maintaining them through different adaptive mechanisms. Here, we tested whether maximum sprint speed of a lizard that shows conservative thermal ecology along a 2200-meter elevational gradient differs with body temperature in lizards from different elevations. Lizards ran faster at optimum than at suboptimum body temperature. Notably, high-elevation lizards were not faster than mid- and low-elevation lizards at suboptimum body temperature, despite their low-quality thermal environment. This result suggests that both preferred body temperature and thermal dependence of speed performance are co-adapted along the elevational gradient. High-elevation lizards display a number of thermoregulatory strategies that allow them to achieve high optimum body temperatures in a low thermal-quality habitat and thus maximize speed performance. As for reproductive condition, we did not find any effect of it on sprint speed, or any significant interaction with elevation or body temperature. However, strikingly, gravid females were significantly slower than males and non-gravid females at suboptimum temperature, but performed similarly well at optimal temperature.
Assuntos
Altitude , Lagartos/fisiologia , Corrida/fisiologia , Animais , Temperatura Corporal/fisiologia , Regulação da Temperatura Corporal/fisiologia , Temperatura Baixa , Ecologia , Ecossistema , Feminino , Número de Gestações , Masculino , Atividade Motora/fisiologia , Reprodução/fisiologia , Caracteres SexuaisRESUMO
INTRODUCTION: Legionellosis is a multisystem bacterial disease, which causes pneumonia with high mortality in patients with comorbidity and admitted in intensive care units (ICU). OBJECTIVE: Determine predictors of mortality or ICU admission. METHODS: Retrospective follow-up of patients diagnosed with Legionella pneumophila pneumonia in Complexo Hospitalario Universitario de A Coruña. Period 2000-2013 (n=240). Analysis of multivariate logistic regression was performed. RESULTS: Mean age was 57.2±15.4 years old, 88.3% were male. Average score of comorbidity (Charlson score) was 2.3±2.3. There was a clear seasonal variation. Predominant symptoms were fever (92.5%), dry cough (38.1%) and dyspnea (33.9%). Creatinine clearance was lower than 60 mL/min/1.73 m² in 29.7% and sodium<135 mEq/l in 58.3%. Admission to ICU rate was 16.3% and 10.8% needs mechanical ventilation. Inhospital mortality rate was 4.6%, rising to 23.1% in patients admitted to ICU. Variables associated to predict ICU admission were age (OR=0.96), liver disease (OR=7.13), dyspnea (OR=4.33), delirium (OR=5.86) and high levels of lactatedehydrogenase (OR=1.002). Variables associated with inhospital mortality were Charlson index (OR=1.70), mechanical ventilation (OR=31.44) and high levels of lactatedehydrogenase (OR=1.002). DISCUSSION: Younger patients with liver disease, dyspnea and confusion are more likely to be admitted to ICU. Comorbidity, mechanical ventilation and elevated LDH levels are associated with higher mortality rate.
Assuntos
Hospitalização , Legionella pneumophila , Doença dos Legionários/diagnóstico , Pneumonia Bacteriana/microbiologia , Adulto , Fatores Etários , Idoso , Comorbidade , Creatinina/metabolismo , Delírio/epidemiologia , Dispneia/epidemiologia , Feminino , Mortalidade Hospitalar , Hospitalização/estatística & dados numéricos , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , L-Lactato Desidrogenase/sangue , Doença dos Legionários/mortalidade , Hepatopatias/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pneumonia Bacteriana/mortalidade , Prognóstico , Estudos Retrospectivos , Estações do Ano , Espanha/epidemiologiaRESUMO
AIMS: Focal adhesions have been associated with poor prognosis in multiple cancer types, but their prognostic value in diffuse large B-cell lymphoma (DLBCL) has not been evaluated. The aim of this study was to investigate the expression patterns and the prognostic value of the focal adhesion proteins FAK, Pyk2, p130Cas and HEF1 in DLBCL. METHODS AND RESULTS: Focal adhesion protein expression was examined using immunohistochemistry in normal lymphoid tissues and in 60 DLBCL patient samples. Kaplan-Meier survival and Cox regression analysis were performed to evaluate the correlation of focal adhesion protein expression with patient prognosis. FAK, Pyk2, p130Cas and HEF1 expression was mostly found in the germinal centres of normal human lymphoid tissues. When assessed in DLBCL samples, FAK, Pyk2, p130Cas and HEF1 were highly expressed in 45%, 34%, 42% and 45% of the samples, respectively. Multivariate Cox analysis revealed that decreased FAK expression was a significant independent predictor of poorer disease outcome. CONCLUSIONS: FAK expression is an independent prognostic factor in DLBCL. Our results suggest that the addition of FAK immunostaining to the current immunohistochemical algorithms may facilitate risk stratification of DLBCL patients.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Biomarcadores Tumorais/análise , Proteína Substrato Associada a Crk/biossíntese , Proteína-Tirosina Quinases de Adesão Focal/biossíntese , Linfoma Difuso de Grandes Células B/patologia , Fosfoproteínas/biossíntese , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Análise Serial de TecidosRESUMO
By recruiting functional domains supporting DNA condensation, cell binding, internalization, endosomal escape and nuclear transport, modular single-chain polypeptides can be tailored to associate with cargo DNA for cell-targeted gene therapy. Recently, an emerging architectonic principle at the nanoscale has permitted tagging protein monomers for self-organization as protein-only nanoparticles. We have studied here the accommodation of plasmid DNA into protein nanoparticles assembled with the synergistic assistance of end terminal poly-arginines (R9) and poly-histidines (H6). Data indicate a virus-like organization of the complexes, in which a DNA core is surrounded by a solvent-exposed protein layer. This finding validates end-terminal cationic peptides as pleiotropic tags in protein building blocks for the mimicry of viral architecture in artificial viruses, representing a promising alternative to the conventional use of viruses and virus-like particles for nanomedicine and gene therapy. FROM THE CLINICAL EDITOR: Finding efficient gene delivery methods still represents a challenge and is one of the bottlenecks to the more widespread application of gene therapy. The findings presented in this paper validate the application of end-terminal cationic peptides as pleiotropic tags in protein building blocks for "viral architecture mimicking" in artificial viruses, representing a promising alternative to the use of viruses and virus-like particles for gene delivery.
Assuntos
DNA/administração & dosagem , Técnicas de Transferência de Genes , Nanopartículas/química , Proteínas/química , Sequência de Aminoácidos , DNA/genética , Terapia Genética , Células HeLa , Histidina/química , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Peptídeos/químicaRESUMO
BACKGROUND: Reactive oxidative stress is a critical player in the amyloid beta (Aß) toxicity that contributes to neurodegeneration in Alzheimer's disease (AD). Damaged mitochondria are one of the main sources of reactive oxygen species and accumulate in Aß plaque-associated dystrophic neurites in the AD brain. Although Aß causes neuronal mitochondria reactive oxidative stress in vitro, this has never been directly observed in vivo in the living mouse brain. Here, we tested for the first time whether Aß plaques and soluble Aß oligomers induce mitochondrial oxidative stress in surrounding neurons in vivo, and whether this neurotoxic effect can be abrogated using mitochondrial-targeted antioxidants. METHODS: We expressed a genetically encoded fluorescent ratiometric mitochondria-targeted reporter of oxidative stress in mouse models of the disease and performed intravital multiphoton microscopy of neuronal mitochondria and Aß plaques. RESULTS: For the first time, we demonstrated by direct observation in the living mouse brain exacerbated mitochondrial oxidative stress in neurons after both Aß plaque deposition and direct application of soluble oligomeric Aß onto the brain, and determined the most likely pathological sequence of events leading to oxidative stress in vivo. Oxidative stress could be inhibited by both blocking calcium influx into mitochondria and treating with the mitochondria-targeted antioxidant SS31. Remarkably, the latter ameliorated plaque-associated dystrophic neurites without impacting Aß plaque burden. CONCLUSIONS: Considering these results, combination of mitochondria-targeted compounds with other anti-amyloid beta or anti-tau therapies hold promise as neuroprotective drugs for the prevention and/or treatment of AD.
Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Camundongos , Animais , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/metabolismo , Estresse Oxidativo/fisiologia , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Oxirredução , Mitocôndrias/metabolismo , Modelos Animais de DoençasRESUMO
Focal adhesion (FA) proteins have been associated with transformation, migration, metastasis, and poor outcome in many neoplasias. We previously showed that these proteins were inhibited by E7123, a new celecoxib derivative with antitumor activity, in acute myeloid leukemia. However, little is known about FAs in diffuse large B cell lymphoma (DLBCL). This paper aimed to determine whether E7123 was effective against DLBCL and whether FAs were involved in its action. We evaluated the cytotoxicity and mechanism of action of E7123 and celecoxib in DLBCL cell lines. We also assessed the E7123 in vivo activity in a DLBCL xenograft model and studied FA signaling in primary DLBCL patient samples. We found that E7123 showed higher antitumor effect than celecoxib against DLBCL cells. Its mechanism of action involved deregulation of FA, AKT, and Mcl-1 proteins, a pathway that is activated in some patient samples, apoptosis-inducing factor release and induction of caspase-independent cell death. Moreover, E7123 showed suppression of in vivo tumor growth. These findings indicate that E7123 is effective against DLBCL in vitro and in vivo, with a mechanism of action that differs from that of most current therapies for this malignancy. Our results support further preclinical evaluation of E7123.
Assuntos
Antineoplásicos/farmacologia , Adesões Focais/efeitos dos fármacos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Pirazóis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia , Animais , Antineoplásicos/uso terapêutico , Caspases/metabolismo , Celecoxib , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proteína Substrato Associada a Crk/genética , Inibidores de Ciclo-Oxigenase 2/farmacologia , Fragmentação do DNA/efeitos dos fármacos , Adesões Focais/metabolismo , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Camundongos , Camundongos Nus , Proteína de Sequência 1 de Leucemia de Células Mieloides , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Pirazóis/uso terapêutico , Sulfonamidas/uso terapêutico , Células Tumorais Cultivadas , Regulação para CimaRESUMO
Central nervous system dissemination is a relatively uncommon but almost always fatal complication in diffuse large B-cell lymphoma patients. Optimal therapy for central nervous involvement in this malignancy has not been established. In this paper, we aimed to evaluate the therapeutic effect of E7123, a celecoxib derivative that inhibits focal adhesion signaling, in a novel xenograft model of diffuse large B-cell lymphoma with central nervous system involvement. Cells obtained after disaggregation of HT subcutaneous tumors (HT-SC cells) were intravenously injected in NOD/SCID mice. These mice received oral vehicle or 75 mg/kg of E7123 daily until they were euthanized for weight loss or signs of sickness. The antitumor effect of E7123 was validated in an independent experiment using a bioluminescent mouse model. Intravenously injected HT-SC cells showed higher take rate and higher central nervous system tropism (associated with increased expression of ß1-integrin and p130Cas proteins) than HT cells. The oral administration of E7123 significantly increased survival time in 2 independent experiments using mice injected with unmodified or bioluminescent HT-SC cells. We have developed a new xenograft model of diffuse large B-cell lymphoma with central nervous system involvement that can be used in the pre-clinical evaluation of new drugs for this malignancy. E7123 is a new, well-tolerated and orally available therapeutic agent that merits further investigation since it may improve current management of diffuse large B-cell lymphoma patients with central nervous system involvement.
Assuntos
Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Adesões Focais/efeitos dos fármacos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Pirazóis/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Administração Oral , Animais , Linhagem Celular Tumoral , Neoplasias do Sistema Nervoso Central/mortalidade , Neoplasias do Sistema Nervoso Central/patologia , Adesões Focais/patologia , Humanos , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Distribuição Aleatória , Transdução de Sinais/fisiologia , Taxa de Sobrevida/tendênciasRESUMO
Microglia are brain-resident myeloid cells and play a major role in the innate immune responses of the CNS and the pathogenesis of Alzheimer's disease (AD). However, the contribution of nonparenchymal or brain-infiltrated myeloid cells to disease progression remains to be demonstrated. Here, we show that monocyte-derived cells (MDC) invade brain parenchyma in advanced stages of AD continuum using transcriptional analysis and immunohistochemical characterization in post-mortem human hippocampus. Our findings demonstrated that a high proportion (60%) of demented Braak V-VI individuals was associated with up-regulation of genes rarely expressed by microglial cells and abundant in monocytes, among which stands the membrane-bound scavenger receptor for haptoglobin/hemoglobin complexes or Cd163. These Cd163-positive MDC invaded the hippocampal parenchyma, acquired a microglial-like morphology, and were located in close proximity to blood vessels. Moreover, and most interesting, these invading monocytes infiltrated the nearby amyloid plaques contributing to plaque-associated myeloid cell heterogeneity. However, in aged-matched control individuals with hippocampal amyloid pathology, no signs of MDC brain infiltration or plaque invasion were found. The previously reported microglial degeneration/dysfunction in AD hippocampus could be a key pathological factor inducing MDC recruitment. Our data suggest a clear association between MDC infiltration and endothelial activation which in turn may contribute to damage of the blood brain barrier integrity. The recruitment of monocytes could be a consequence rather than the cause of the severity of the disease. Whether monocyte infiltration is beneficial or detrimental to AD pathology remains to be fully elucidated. These findings open the opportunity to design targeted therapies, not only for microglia but also for the peripheral immune cell population to modulate amyloid pathology and provide a better understanding of the immunological mechanisms underlying the progression of AD.
Assuntos
Doença de Alzheimer , Monócitos , Humanos , Idoso , Placa Amiloide , Encéfalo , Hipocampo , Proteínas AmiloidogênicasRESUMO
BACKGROUND: Lenvatinib, a tyrosine kinase inhibitor (TKI) approved for the treatment of progressive and radioactive iodine (RAI)-refractory differentiated thyroid cancer (DTC), is associated with significant adverse effects that can be partially mitigated through the development of novel drug formulations. The utilization of nanoparticles presents a viable option, as it allows for targeted drug delivery, reducing certain side effects and enhancing the overall quality of life for patients. This study aimed to produce and assess, both in vitro and in vivo, the cytotoxicity, biodistribution, and therapeutic efficacy of lenvatinib-loaded PLGA nanoparticles (NPs), both with and without decoration using antibody conjugation (cetuximab), as a novel therapeutic approach for managing aggressive thyroid tumors. METHODS: Poly(lactic-co-glycolic acid) nanoparticles (NPs), decorated with or without anti-EGFR, were employed as a lenvatinib delivery system. These NPs were characterized for size distribution, surface morphology, surface charge, and drug encapsulation efficiency. Cytotoxicity was evaluated through MTT assays using two cellular models, one representing normal thyroid cells (Nthy-ori 3-1) and the other representing anaplastic thyroid cells (CAL-62). Additionally, an in vivo xenograft mouse model was established to investigate biodistribution and therapeutic efficacy following intragastric administration. RESULTS: The NPs demonstrated success in terms of particle size, polydispersity index (PDI), zeta potential, morphology, encapsulation efficiency, and cetuximab distribution across the surface. In vitro analysis revealed cytotoxicity in both cellular models with both formulations, but only the decorated NPs achieved an ID50 value in CAL-62 cells. Biodistribution analysis following intragastric administration in xenografted thyroid mice demonstrated good stability in terms of intestinal barrier function and tumor accumulation. Both formulations were generally well tolerated without inducing pathological effects in the examined organs. Importantly, both formulations increased tumor necrosis; however, decorated NPs exhibited enhanced parameters related to apoptotic/karyolytic forms, mitotic index, and vascularization compared with NPs without decoration. CONCLUSIONS: These proof-of-concept findings suggest a promising strategy for administering TKIs in a more targeted and effective manner.