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2.
Leukemia ; 32(4): 1003-1015, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29158557

RESUMO

Dendritic cells (DCs) have a key role in regulating tumor immunity, tumor cell growth and drug resistance. We hypothesized that multiple myeloma (MM) cells might recruit and reprogram DCs to a tumor-permissive phenotype by changes within their microRNA (miRNA) network. By analyzing six different miRNA-profiling data sets, miR-29b was identified as the only miRNA upregulated in normal mature DCs and significantly downregulated in tumor-associated DCs. This finding was validated in primary DCs co-cultured in vitro with MM cell lines and in primary bone marrow DCs from MM patients. In DCs co-cultured with MM cells, enforced expression of miR-29b counteracted pro-inflammatory pathways, including signal transducer and activator of transcription 3 and nuclear factor-κB, and cytokine/chemokine signaling networks, which correlated with patients' adverse prognosis and development of bone disease. Moreover, miR-29b downregulated interleukin-23 in vitro and in the SCID-synth-hu in vivo model, and antagonized a Th17 inflammatory response. All together, these effects translated into strong anti-proliferative activity and reduction of genomic instability of MM cells. Our study demonstrates that MM reprograms the DCs functional phenotype by downregulating miR-29b whose reconstitution impairs DCs ability to sustain MM cell growth and survival. These results underscore miR-29b as an innovative and attractive candidate for miRNA-based immune therapy of MM.


Assuntos
Células Dendríticas/patologia , Inflamação/genética , MicroRNAs/genética , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Animais , Medula Óssea/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , Camundongos SCID , NF-kappa B/genética , Fator de Transcrição STAT3/genética , Regulação para Cima/genética
3.
Leukemia ; 32(4): 996-1002, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29158558

RESUMO

Arginine methyltransferases critically regulate cellular homeostasis by modulating the functional outcome of their substrates. The protein arginine methyltransferase 5 (PRMT5) is an enzyme involved in growth and survival pathways promoting tumorigenesis. However, little is known about the biologic function of PRMT5 and its therapeutic potential in multiple myeloma (MM). In the present study, we identified and validated PRMT5 as a new therapeutic target in MM. PRMT5 is overexpressed in patient MM cells and associated with decreased progression-free survival and overall survival. Either genetic knockdown or pharmacological inhibition of PRMT5 with the inhibitor EPZ015666 significantly inhibited growth of both cell lines and patient MM cells. Furthermore, PRMT5 inhibition abrogated NF-κB signaling. Interestingly, mass spectrometry identified a tripartite motif-containing protein 21 TRIM21 as a new PRMT5-partner, and we delineated a TRIM21-dependent mechanism of NF-κB inhibition. Importantly, oral administration of EPZ015666 significantly decreased MM growth in a humanized murine model of MM. These data both demonstrate the oncogenic role and prognostic relevance of PRMT5 in MM pathogenesis, and provide the rationale for novel therapies targeting PRMT5 to improve patient outcome.


Assuntos
Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Proteína-Arginina N-Metiltransferases/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Humanos , Isoquinolinas/farmacologia , NF-kappa B/metabolismo , Prognóstico , Pirimidinas/farmacologia , Ribonucleoproteínas/metabolismo , Transdução de Sinais/efeitos dos fármacos
4.
Artigo em Inglês | MEDLINE | ID: mdl-28295762

RESUMO

The role of spirituality on the psychological health was mostly investigated through studies conducted in terminally ill patients. However, there are not studies investigating the role of religious and spiritual beliefs on psychological state and on burden dimensions in caregivers. The purpose of this study was to investigate the association between spirituality, burden, and psychological state in caregivers of terminally ill cancer patients. Two hundred caregivers of terminally ill patients with cancer were interviewed using Prolonged Grief Disorder 12 (PG-12), Hamilton Anxiety Rating Scale (HAM-A), Hamilton Depression Scale (HAM-D), Caregiver Burden Inventory (CBI) and System of Belief Inventory (SBI-15R). The caregiver burden was positively correlated with anxiety, depression and PG-12 scores. The intrinsic spirituality was a significant predictor of the time-dependence burden (positively associated); and of the emotional burden (negatively associated). In caregivers of terminally ill cancer patients, higher levels of intrinsic spirituality predicted a higher amount of time devote to caregiving, and also protected against the emotional distress linked to providing assistance.


Assuntos
Cuidadores/psicologia , Efeitos Psicossociais da Doença , Neoplasias/psicologia , Espiritualidade , Assistência Terminal/psicologia , Adaptação Psicológica , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doente Terminal
5.
Leukemia ; 31(7): 1570-1581, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27890927

RESUMO

Despite therapeutic advances, multiple myeloma (MM) remains an incurable disease, predominantly because of the development of drug resistance. The activator protein-1 (AP-1) transcription factor family has been implicated in a multitude of physiologic processes and tumorigenesis; however, its role in MM is largely unknown. Here we demonstrate specific and rapid induction of the AP-1 family member JunB in MM cells when co-cultured with bone marrow stromal cells. Supporting a functional key role of JunB in MM pathogenesis, knockdown of JUNB significantly inhibited in vitro MM cell proliferation and survival. Consistently, induced silencing of JUNB markedly decreased tumor growth in a murine MM model of the microenvironment. Subsequent gene expression profiling revealed a role for genes associated with apoptosis, DNA replication and metabolism in driving the JunB-mediated phenotype in MM cells. Importantly, knockdown of JUNB restored the response to dexamethasone in dexamethasone-resistant MM cells. Moreover, 4-hydroxytamoxifen-induced activation of a JunB-ER fusion protein protected dexamethasone-sensitive MM cells against dexamethasone- and bortezomib-induced cytotoxicity. In summary, our results demonstrate for the first time a specific role for AP-1/JunB in MM cell proliferation, survival and drug resistance, thereby strongly supporting that this transcription factor is a promising new therapeutic target in MM.


Assuntos
Medula Óssea/patologia , Mieloma Múltiplo/patologia , Fatores de Transcrição/fisiologia , Microambiente Tumoral , Animais , Bortezomib/farmacologia , Proliferação de Células , Dexametasona/farmacologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Camundongos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/mortalidade , NF-kappa B/fisiologia
7.
Leukemia ; 29(11): 2173-83, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25987254

RESUMO

Interferon regulatory factor 4 (IRF4) is an attractive therapeutic target in multiple myeloma (MM). We here report that expression of IRF4 mRNA inversely correlates with microRNA (miR)-125b in MM patients. Moreover, we provide evidence that miR-125b is downregulated in TC2/3 molecular MM subgroups and in established cell lines. Importantly, constitutive expression of miR-125b-5p by lentiviral vectors or transfection with synthetic mimics impaired growth and survival of MM cells and overcame the protective role of bone marrow stromal cells in vitro. Apoptotic and autophagy-associated cell death were triggered in MM cells on miR-125b-5p ectopic expression. Importantly, we found that the anti-MM activity of miR-125b-5p was mediated via direct downregulation of IRF4 and its downstream effector BLIMP-1. Moreover, inhibition of IRF4 translated into downregulation of c-Myc, caspase-10 and cFlip, relevant IRF4-downstream effectors. Finally, in vivo intra-tumor or systemic delivery of formulated miR-125b-5p mimics against human MM xenografts in severe combined immunodeficient/non-obese diabetic mice induced significant anti-tumor activity and prolonged survival. Taken together, our findings provide evidence that miR-125b, differently from other hematologic malignancies, has tumor-suppressor activity in MM. Furthermore, our data provide proof-of-concept that synthetic miR-125b-5p mimics are promising anti-MM agents to be validated in early clinical trials.


Assuntos
Fatores Reguladores de Interferon/genética , MicroRNAs/fisiologia , Mieloma Múltiplo/terapia , Animais , Apoptose , Autofagia , Linhagem Celular Tumoral , Proliferação de Células , Genes Supressores de Tumor/fisiologia , Humanos , Masculino , Camundongos , Mieloma Múltiplo/patologia
8.
Reumatismo ; 67(3): 97-102, 2015 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-26876188

RESUMO

The aim of this study was to assess circulating levels of reactive oxygen metabolites (ROMs) as a marker of oxidative stress in rheumatoid arthritis (RA) patients during an anti-tumor necrosis factor alpha (TNF-α) treatment. We enrolled 40 patients with RA (36 females; age 53 ± 13 yrs) treated with different subcutaneously administered TNF-α inhibitors. The oxidative status was determined on the basis of plasma samples taken before, at 24 and 52 weeks of the anti-TNF-α treatment. Hydroperoxide levels were measured using the d-ROMs test, a useful clinically proven oxidative stress marker. During the anti-TNF-α therapy, we observed a significant reduction in serum ROMs levels in RA patients from 33.2 ± 10 mg H2O2/L at baseline to 29.5 ± 7 and 29.3 ± 9 mg H2O2/L, at 24 and 52 weeks, respectively (p<0.05). We also identified a significant correlation between the oxidative stress status and the disease activity score on 28 joints/C-reactive protein and health assessment questionnaire disability index. The results of our study demonstrate that a good control of the disease with anti-TNF-α agents can reduce oxidative stress in RA patients. However, further studies of larger patient cohorts are needed to confirm these preliminary data.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Proteína C-Reativa/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto , Idoso , Artrite Reumatoide/sangue , Biomarcadores/sangue , Feminino , Humanos , Peróxido de Hidrogênio/metabolismo , Masculino , Pessoa de Meia-Idade , Oxidantes/metabolismo
9.
Eur Biophys J ; 40(11): 1237-45, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21750910

RESUMO

We evaluated the potential of tryptophan (Trp) phosphorescence spectroscopy for investigating conformational states of proteins involved in interaction with nanoparticles. Characterization of protein-nanoparticle interaction is crucial in assessing biological hazards related to use of nanoparticles. We synthesized glutathione-coated CdS quantum dots (GSH-CdS), which exhibited an absorption peak at 366 nm, indicative of 2.4 nm core size. Chemical analysis of purified GSH-CdS suggested an average molecular formula of GSH18S56Cd60. Investigations were conducted on model proteins varying in terms of isoelectric point, degree of burial of the Trp probe, and quaternary structure. GSH-CdS fluorescence measurements showed improvement in nanoparticle quantum yield induced by protein interaction. Trp phosphorescence was used to examine the possible perturbations in the protein native fold induced by GSH-CdS. Phosphorescence lifetime measurements highlighted significant conformational changes in some proteins. Despite their small size, GSH-CdS appeared to interact with more than one protein molecule. Rough determination of the affinity of GSH-CdS for proteins was derived from the change in phosphorescence lifetime at increasing nanoparticle concentrations. The estimated affinities were comparable to those observed for specific protein-ligand interactions and suggest that protein-nanoparticle interaction may have a biological impact.


Assuntos
Compostos de Cádmio/química , Glutationa/química , Glutationa/farmacologia , Medições Luminescentes , Proteínas/química , Pontos Quânticos , Sulfetos/química , Triptofano/química , Animais , Geobacillus stearothermophilus/enzimologia , Modelos Moleculares , Conformação Proteica/efeitos dos fármacos , Coelhos
10.
Infez Med ; 17(4): 240-3, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20046105

RESUMO

A case of prosthetic valve endocarditis due to methicillin susceptible Staphylococcus aureus (MSSA) with cerebral metastatic seeding is described. The patient is a 61 year old man with diabetes mellitus, chronic renal failure and previous bacterial endocarditis. Despite appropriate MSSA therapy, the patient was eventually cured with the introduction of linezolid, without needing surgical intervention.


Assuntos
Acetamidas/uso terapêutico , Anti-Infecciosos/uso terapêutico , Valva Aórtica/cirurgia , Endocardite Bacteriana/tratamento farmacológico , Endocardite Bacteriana/etiologia , Próteses Valvulares Cardíacas/efeitos adversos , Embolia Intracraniana/tratamento farmacológico , Staphylococcus aureus Resistente à Meticilina , Oxacilina/uso terapêutico , Oxazolidinonas/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Teicoplanina/uso terapêutico , Humanos , Linezolida , Masculino , Resultado do Tratamento
12.
Braz. j. biol ; 66(1a): 117-120, Feb. 2006. ilus, tab
Artigo em Inglês | LILACS | ID: lil-426273

RESUMO

Neste trabalho, se descrevem a larva do último instar e a pupa do Paramallocera hirta Kirby, 1818, com base em espécimes criados em laboratório a partir de larvas neonatas em toras de Eucalyptus globulus ssp. globulus e com uma dieta artificial. Apresentam-se, também, características com possível valor diagnóstico.


Assuntos
Animais , Besouros/anatomia & histologia , Besouros/crescimento & desenvolvimento , Eucalyptus/parasitologia , Larva/anatomia & histologia , Pupa/anatomia & histologia , Uruguai
13.
Braz. j. biol ; 66(1)2006.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467781

RESUMO

Last instar larva and pupa of Paramallocera hirta Kirby, 1818 are described and illustrated based on specimens reared in the laboratory from neonate larvae on Eucalyptus globulus ssp. globulus logs and on an artificial diet. Characteristics of possible diagnostic value are also presented in this paper.


Neste trabalho, se descrevem a larva do último instar e a pupa do Paramallocera hirta Kirby, 1818, com base em espécimes criados em laboratório a partir de larvas neonatas em toras de Eucalyptus globulus ssp. globulus e com uma dieta artificial. Apresentam-se, também, características com possível valor diagnóstico.

14.
Braz. j. biol ; 65(1): 97-100, Feb. 2005. ilus
Artigo em Inglês | LILACS | ID: lil-416974

RESUMO

Neste trabalho são descritas a larva do último instar e a pupa de Eurymerus eburioides Audinet-Serville, 1833, com base em espécimes criados em laboratório a partir de larvas neonatas de Eucalyptus globulus globulus. Apresentam-se, também, características com possível valor diagnóstico.


Assuntos
Animais , Feminino , Masculino , Besouros/anatomia & histologia , Besouros/crescimento & desenvolvimento , Larva/anatomia & histologia , Pupa/anatomia & histologia
15.
J Sports Med Phys Fitness ; 44(1): 49-53, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15181390

RESUMO

AIM: It has been reported that rhythmic gymnasts are at risk of suffering from low back injuries, because of repetitive lumbar hyperextensions. On the other hand, this sport requires features of leanness, muscular strength and flexibility that should represent protective factors for back pain. METHODS: This cross-sectional study aimed to assess the prevalence of low back pain in 67 club-level competitive rhythmic gymnasts aged 13-19 years. A standardized questionnaire was used to evaluate back-pain symptoms. Anthropometric measurements, time spent in physical activity, psychological testing results, smoking habits and age of menarche were recorded. One hundred and four age-matched general females served as control group. RESULTS: Low back pain complaints were reported by 7 rhythmic gymnasts and by 27 controls (10.4% vs 26.0%, p<0.05); the prevalent location of back pain was bilateral in gymnasts and central in controls. Gymnasts had lower body weight, body mass index, fat body mass and delayed menarche. The females with low-back pain displayed higher body weight, body mass index, fat body mass, age, a greater smoking habit and more anxious/depressive behaviour, both in the gymnast and in the control group. CONCLUSION: Competitive, club-level rhythmic gymnasts show a reduced prevalence of low back-pain. Being younger in age, having greater leanness, not smoking, displaying less anxious/depressive behaviour, and developing increased muscle strength and flexibility, all can represent preventive factors for low back pain. This study suggests that rhythmic gymnastics is not a discipline at increased risk of low back pain.


Assuntos
Ginástica/lesões , Dor Lombar/epidemiologia , Adolescente , Adulto , Índice de Massa Corporal , Estudos de Casos e Controles , Estudos Transversais , Feminino , Ginástica/fisiologia , Humanos , Itália/epidemiologia , Dor Lombar/etiologia , Dor Lombar/fisiopatologia , Vértebras Lombares/patologia , Vértebras Lombares/fisiologia , Músculo Esquelético/fisiologia , Educação Física e Treinamento/métodos , Postura/fisiologia , Prevalência , Fatores de Risco , Inquéritos e Questionários
16.
Braz. j. biol ; 62(4b): 853-860, Nov. 2002. ilus
Artigo em Inglês | LILACS | ID: lil-339385

RESUMO

The description of the last instar larva and pupa of Phoracantha recurva Newman, 1842 and the redescription of the immature stages of Phoracantha semipunctata Fabricius, 1775 showing new characters of possible diagnostic value are presented in this work. A key of identification of both species based on these characters is also given


Assuntos
Animais , Besouros , Larva , Microscopia Eletrônica de Varredura , Pupa
17.
Braz. j. biol ; 62(4)2002.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467681

RESUMO

The description of the last instar larva and pupa of Phoracantha recurva Newman, 1842 and the redescription of the immature stages of Phoracantha semipunctata Fabricius, 1775 showing new characters of possible diagnostic value are presented in this work. A key of identification of both species based on these characters is also given.


O presente trabalho se refere à descrição do último ínstar larval e da pupa do Phoracantha recurva Newman, 1842, e à redescrição dos ínstares imaturos do Phoracantha semipunctata Fabricius, 1775, com base em novos caracteres morfológicos úteis para identificação das espécies. Além de apresentar uma chave para a identificação de larvas dessas espécies.

18.
Mar Environ Res ; 52(4): 383-95, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11695656

RESUMO

The synthesis of phytochelatins (PC), intracellular metal-binding polypeptides characterized by a repeating sequence of gamma-glutamic acid- cysteine (gamma-Glu-Cys) pairs, has been studied in laboratory cultures of the marine diatom Phaeodactylum tricornutum exposed to Cd, Pb or Zn. Cd and Pb were able to induce PC of different degree of polymerization. The accumulation of the peptides follows a direct relationship with the metal exposure. No PC induction was observed in Zn-treated cultures, although the intracellular concentration of Zn increased during exposure. Both in short-term (7 h exposure, 10 microM Cd or Pb) and 3-day experiments (metal concentration less than 0.5 microM), the major fraction of total PC gamma-Glu-Cys subunits synthesized was polymerized as PC2 when cells were exposed to Pb, but as PC4 when cells were exposed to Cd. In short-term experiments about 50% of the gamma-Glu-Cys residues of the cellular pool of glutathione was quickly and almost quantitatively converted into PC. Recovery experiments, in which metal-stressed cells are suspended in a metal-free medium, showed a decrease of the PC pool and a concomitant increase of glutathione, suggesting a mechanism of degradation and release of metal-phytochelatin complexes.


Assuntos
Cádmio/efeitos adversos , Quelantes/química , Diatomáceas/fisiologia , Dipeptídeos/química , Chumbo/efeitos adversos , Metaloproteínas/biossíntese , Poluentes da Água/efeitos adversos , Biodegradação Ambiental , Cádmio/metabolismo , Glutationa , Chumbo/metabolismo , Metaloproteínas/química , Fotoquímica , Fitoquelatinas
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