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1.
ESMO Open ; 7(3): 100465, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35427835

RESUMO

BACKGROUND: Frontline immune checkpoint inhibitors (ICI)-based regimens in non-oncogene-addicted non-small-cell lung cancer (NSCLC) have been deeply investigated. To rank the available therapeutic options, we carried out a systematic review and Bayesian meta-analysis. METHODS: A comprehensive search for randomized controlled trials (RCTs) of ICI regimens, and a pairwise and a network meta-analysis (NMA) with an all-comers and a stratified strategy were conducted. Endpoints were overall survival (OS), progression-free survival (PFS), objective response rate (ORR) and treatment-related adverse events (TRAEs). RESULTS: Nineteen RCTs involving 17 treatment regimens were included. For the all-comers population, pembrolizumab/chemotherapy (CT) and cemiplimab were most likely the best treatments. For programmed death-ligand 1 (PD-L1) <1% nivolumab/ipilimumab with/without CT, for PD-L1 >1% and 1%-49% pembrolizumab/CT and for PD-L1 >50% cemiplimab ranked first for OS. In non-squamous (NSQ), pembrolizumab with/without CT ranked first for OS; cemiplimab ranked worse than the unselected population. In squamous (SQ), pooled hazard ratio (HR) showed a better chance in improving efficacy for combination strategy, while monotherapy did not, except for cemiplimab that ranked second. Atezolizumab/CT/bevacizumab ranked first in most subgroups for PFS. Direct comparison showed a non-statistically significant benefit of ICI regimens for the liver metastases cohort in OS, with a good ranking for pembrolizumab/CT and atezolizumab/bevacizumab/CT. Regarding brain metastases, all ICI regimens demonstrated an improvement in OS and PFS compared to CT. Nivolumab/ipilimumab/CT ranked better in this subset. CONCLUSIONS: Our meta-analysis updated on the most recent findings demonstrates that different ICI treatments rank differently in specific NSCLC settings (histology, biomarker and clinical presentation) offering a novel challenging scenario for clinical decision making and research planning.


Assuntos
Antineoplásicos Imunológicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antineoplásicos Imunológicos/efeitos adversos , Antígeno B7-H1 , Bevacizumab/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Ipilimumab/uso terapêutico , Neoplasias Pulmonares/patologia , Nivolumabe/uso terapêutico
2.
Stem Cell Res ; 10(1): 85-94, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23142801

RESUMO

Neural stem cells (NSCs) raised the hope for cell-based therapies in human neurodevelopmental and neurodegenerative diseases. Current research strategies aim to isolate, enrich, and propagate homogeneous populations of neural stem cells. Unfortunately, several concerns with NSC cultures currently may limit their therapeutic promise. Exhaustion of growth factors and/or their uncontrolled release with burst and fall in their concentration may greatly affect the in vitro behavior of NSCs. In this context, we investigate whether a device containing heparan sulfate (HS), which is a co-factor in growth factor-mediated cell proliferation and differentiation, could potentiate and prolong the delivery of fibroblast growth factor-2 (FGF-2) and thus improve in vitro NSC cultivation. We demonstrated that NSCs cultivated in media with a controlled release of FGF-2 from a polyelectrolyte polymer showed a higher proliferation rate, and reduced apoptosis and senescence. In these experimental conditions NSCs preserve their stemness properties for a longer period of time compared with controls. Also of interest is that cell fate properties are conserved as well. The controlled release of FGF-2 reduced the level of oxidative stress and this is associated with a lower level of damaged DNA. This result may explain the reduced level of senescence and apoptosis in NSCs cultivated in the presence of hydrogel-releasing FGF-2.


Assuntos
Técnicas de Cultura de Células/métodos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Células-Tronco Neurais/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Eletrólitos/química , Heparitina Sulfato/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Cinética , Camundongos , Células-Tronco Neurais/citologia , Polímeros/química
4.
J Thromb Haemost ; 4(4): 848-60, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16634756

RESUMO

BACKGROUND: Megakaryopoiesis represents a multi-step, often unclear, process leading to commitment, differentiation, and maturation of megakaryocytes (MKs) that release platelets. AIM: To identify the novel genes that might help to clarify the molecular mechanisms of megakaryocytopoiesis and be regarded as potential candidates of inherited platelet defects, global gene expression of hematopoietic lineages was carried out. METHODS: Human cord blood was used to purify CD34+ stem cells and in vitro expand CD41+ cells and burst-forming unit-erythroid (BFU-E). We investigated the expression profiles of these three hematopoietic lineages in the Affymetrix system and selected genes specifically expressed in MKs by comparing transcripts of the different lineages using the dchip and pam algorithms. RESULTS: A detailed characterization of MK population showed that 99% of cells expressed the CD41 antigen whereas 73% were recognizable as terminally differentiated fetal MKs. The profile of these cells was compared with that of CD34+ cells and BFU-E allowing us to select 70 transcripts (MK-core), which represent not only the genes with a well-known function in MKs, but also novel genes never detected or characterized in these cells. Moreover, the specific expression was confirmed at both RNA and protein levels, thus validating the 'MK-core' isolated by informatics tools. CONCLUSIONS: This is a global gene expression that for the first time depicts a well-characterized population of cord blood-derived fetal MKs. Novel genes have been detected, such as those encoding components of the extracellular matrix and basal membrane, which have been found in the cytoplasm of Mks, suggesting that new physiological aspects of MKs should be studied.


Assuntos
Sangue Fetal/citologia , Glicoproteína IIb da Membrana de Plaquetas/biossíntese , Trombopoese/fisiologia , Anticorpos Monoclonais/metabolismo , Antígenos CD34/biossíntese , Antígenos CD34/metabolismo , Células Precursoras Eritroides/metabolismo , Citometria de Fluxo , Humanos , Técnicas In Vitro , Microscopia de Fluorescência , Família Multigênica , Análise de Sequência com Séries de Oligonucleotídeos , Glicoproteína IIb da Membrana de Plaquetas/química , RNA/química , RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Nat Genet ; 26(1): 103-5, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10973259

RESUMO

The autosomal dominant, giant-platelet disorders, May-Hegglin anomaly (MHA; MIM 155100), Fechtner syndrome (FTNS; MIM 153640) and Sebastian syndrome (SBS), share the triad of thrombocytopenia, large platelets and characteristic leukocyte inclusions ('Döhle-like' bodies). MHA and SBS can be differentiated by subtle ultrastructural leukocyte inclusion features, whereas FTNS is distinguished by the additional Alport-like clinical features of sensorineural deafness, cataracts and nephritis. The similarities between these platelet disorders and our recent refinement of the MHA (ref. 6) and FTNS (ref. 7) disease loci to an overlapping region of 480 kb on chromosome 22 suggested that all three disorders are allelic. Among the identified candidate genes is the gene encoding nonmuscle myosin heavy chain 9 (MYH9; refs 8-10), which is expressed in platelets and upregulated during granulocyte differentiation. We identified six MYH9 mutations (one nonsense and five missense) in seven unrelated probands from MHA, SBS and FTNS families. On the basis of molecular modelling, the two mutations affecting the myosin head were predicted to impose electrostatic and conformational changes, whereas the truncating mutation deleted the unique carboxy-terminal tailpiece. The remaining missense mutations, all affecting highly conserved coiled-coil domain positions, imparted destabilizing electrostatic and polar changes. Thus, our results suggest that mutations in MYH9 result in three megakaryocyte/platelet/leukocyte syndromes and are important in the pathogenesis of sensorineural deafness, cataracts and nephritis.


Assuntos
Transtornos Plaquetários/genética , Leucócitos/patologia , Proteínas Motores Moleculares , Mutação , Cadeias Pesadas de Miosina/genética , Alelos , Sequência de Aminoácidos , Animais , Transtornos Plaquetários/patologia , Catarata/genética , Galinhas , Cromossomos Humanos Par 22 , Cristalografia por Raios X , Citoplasma/metabolismo , Genótipo , Perda Auditiva Neurossensorial/genética , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Músculo Liso/metabolismo , Mutação de Sentido Incorreto , Cadeias Pesadas de Miosina/química , Miosinas/química , Miosinas/genética , Nefrite/genética , Neutrófilos/patologia , Neutrófilos/ultraestrutura , Fenótipo , Conformação Proteica , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , Síndrome , Trombocitopenia/genética
6.
Genomics ; 61(2): 219-26, 1999 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-10534407

RESUMO

In a search for candidate tumor suppressor genes within a 650-kb common region of loss of heterozygosity (LOH) at 16q24.3 in breast cancer tissues, a 2.6-kb cDNA, named copine VII (CPNE7), was characterized. The gene is 2654 bp and codes for a 633-residue protein with high homology to the other members of the copine family, such as copine I, copine III, and N-copine. The predicted amino acid sequence contains two copies of a C2 domain in the N-terminus. Since these domains have been found in several membrane-binding proteins involved in different intracellular processes, copine VII was viewed as a potential tumor suppressor gene. Mutation analysis was carried out by single-strand conformation polymorphism analysis of 18 breast tumor tissue samples with ascertained LOH on chromosome 16q24.3. Since only two polymorphisms were identified, no evidence was found to indicate that copine VII is the tumor suppressor gene at 16q24.3 involved in breast cancer.


Assuntos
Neoplasias da Mama/genética , Cromossomos Humanos Par 16 , Genes Supressores de Tumor , Perda de Heterozigosidade , Proteínas de Membrana/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Cricetinae , Análise Mutacional de DNA , Feminino , Humanos , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Polimorfismo Conformacional de Fita Simples , Alinhamento de Sequência
7.
Genomics ; 56(1): 90-7, 1999 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10036189

RESUMO

In sporadic breast cancer, loss of heterozygosity (LOH) frequently occurs in three discrete regions of the long arm of chromosome 16q, the most telomeric of which is located at 16q24.3. Among the genes mapped to this region, PISSLRE is a plausible candidate tumor suppressor gene. It codes for a putative cyclin-dependent kinase that, as with other members of this family, is likely to be involved in regulating the cell cycle and therefore may have a role in oncogenesis. We characterized the genomic structure of PISSLRE and found that the splicing of this gene is complex. A variety of different transcripts were identified, including those due to cryptic splice sites, exon skipping, insertion of intronic sequences, and exon scrambling. The last phenomenon was observed in a rare PISSLRE transcript in which exons are joined at a nonconsensus splice site in an order different from that predicted by the genomic sequence. To screen the PISSLRE gene in breast tumors with ascertained LOH at 16q24.3, we have analyzed each exon by single-strand conformational polymorphism. No variation was found in the coding sequence, leading us to conclude that another tumor suppressor must be targeted by LOH in sporadic breast cancer.


Assuntos
Neoplasias da Mama/genética , Quinases Ciclina-Dependentes/genética , Proteínas Quinases/genética , Processamento Alternativo , Northern Blotting , Cromossomos Humanos Par 16/genética , Éxons , Feminino , Amplificação de Genes , Genes Supressores de Tumor/genética , Humanos , Perda de Heterozigosidade/genética , Dados de Sequência Molecular
8.
Genomics ; 51(3): 463-7, 1998 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9721219

RESUMO

Fanconi anemia (FA) is a genetically heterogeneous disease with at least eight genes on the basis of complementation groups (FAA to FAH). The analysis of the FAA gene in patients suggested the existence of deletions, none of which have thus far been characterized at the genomic level. A detailed restriction map of the FAA gene with the fine localization of its 43 exons is reported in this paper. We also describe the first two genomic deletions, one of 5.0 kb and another of at least 120 kb. The former was likely the result of a recombination between related Alu sequences. Since these interspersed repeats could generate deletions and insertions by mispairing, rearrangements of this gene are a possibility in those FA families in which FAA mutations have not been identified.


Assuntos
Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Anemia de Fanconi/genética , Proteínas Nucleares , Proteínas/genética , Deleção de Sequência/genética , Sequência de Bases , Éxons/genética , Proteínas de Grupos de Complementação da Anemia de Fanconi , Humanos , Íntrons/genética , Dados de Sequência Molecular , Recombinação Genética/genética , Sequências Repetitivas de Ácido Nucleico/genética , Mapeamento por Restrição , Análise de Sequência de DNA
9.
Haematologica ; 83(6): 533-42, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9676027

RESUMO

BACKGROUND AND OBJECTIVE: Fanconi anemia (FA) is an autosomal recessive disease characterized by pancytopenia, congenital malformation and high predisposition to developing malignancies. The phenotypical heterogeneity is associated with genetic heterogeneity: at least 8 complementation groups (FA-A to FA-H) have been identified, each group presumably corresponding to a separate disease gene (FAA to FAH). The FAA and FAC genes, which account for 75-80% of the patients, have been cloned. Their protein products have no significant homology to any known protein, or to each other, and may therefore represent elements of a new pathway. This review describes some of the recent contributions to the understanding of the molecular basis of FA. EVIDENCE AND INFORMATION SOURCES: The authors of the present review have been working in the field of FA for several years. In the present review they have critically examined articles published in journals covered by the Science Citation Index and Medline. STATE OF ART AND PERSPECTIVE(S): A variety of biochemical and cellular approaches have been used to determine the molecular defect of FA. Evidence for a possible role of the defective proteins in cell cycle regulation, apoptosis, or DNA stability have been reported. Recently, it has been demonstrated that FAA and FAC proteins bind each other and form a complex found in similar abundance in both cytoplasm and nucleus, suggesting a possible function in nucleus activities. Knowledge of the mutation spectrum occurring in the FA genes may contribute significantly to pathogenesis studies in FA and help to design mutation screening strategies. Further functional studies and the cloning of other FA genes will provide insights into the biological basis of FA and information for developing specific therapies for the disease.


Assuntos
Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Anemia de Fanconi/genética , Anemia de Fanconi/metabolismo , Anemia de Fanconi/fisiopatologia , Proteínas Nucleares , Proteínas/genética , Proteínas/metabolismo , Proteínas de Grupos de Complementação da Anemia de Fanconi , Humanos
10.
Genomics ; 41(3): 309-14, 1997 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-9169126

RESUMO

Fanconi anemia (FA) is a genetically heterogenous disease involving at least five genes on the basis of complementation analysis (FAA to FAE). The FAA gene has been recently isolated by two independent approaches, positional and functional cloning. In the present study we describe the genomic structure of the FAA gene. The gene contains 43 exons spanning approximately 80 kb as determined by the alignment of four cosmids and the fine localization of the first and the last exons in restriction fragments of these clones. Exons range from 34 to 188 bp. All but three of the splice sites were consistent with the ag-gt rule. We also describe three alternative splicing events in cDNA clones that result in the loss of exon 37, a 23-bp deletion at the 5' end of exon 41, and a GCAG insertion at the 3' portion also in exon 41. Sequence analysis of the 5' region upstream of the putative transcription start site showed no obvious TATA and CAAT boxes, but did show a GC-rich region, typical of housekeeping genes. Knowledge of the structure of the FAA gene will provide an invaluable resource for the discovery of mutations in the gene that accounts for about 60-66% of FA patients.


Assuntos
Anemia de Fanconi/genética , Processamento Alternativo , Sequência de Bases , Clonagem Molecular , Cosmídeos , DNA Complementar/genética , Éxons , Anemia de Fanconi/metabolismo , Humanos , Íntrons , Dados de Sequência Molecular , Mutação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
11.
Hum Mol Genet ; 6(4): 615-25, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9097968

RESUMO

A gene cloning strategy based on the screening of the Expressed Sequence Tags database (dbEST) using sequences of mitochondrial housekeeping proteins of yeast was employed to identify the cDNA encoding the precursor of the human mitochondrial RNA polymerase (h-mtRPOL). The 3831 bp h-mtRPOL cDNA is located on chromosome 19p13.3 and encodes a protein of 1230 amino acid residues. The protein sequence shows significant homologies with sequences corresponding to mitochondrial RNA polymerases from lower eukaryotes, and to RNA polymerases from several bacteriophages. The mitochondrial RNA polymerase carries out the central activity of mitochondrial gene expression and, by providing the RNA primers for replication-initiation, is also implicated in the maintenance and propagation of the mitochondrial genome. Genes involved in the control of mtDNA replication and gene expression are attractive candidates for human disorders due to abnormalities of nucleo-mitochondrial intergenomic signalling. The availability of the h-mtRPOL cDNA will allow us to test its role in mitochondrial pathology. In addition, we propose the 'cyberscreening' of dbEST, based on yeast/human cross-species comparison, as a powerful, simple, rapid and inexpensive method, that may accelerate several-fold the molecular dissection of the human mitochondrial proteome.


Assuntos
Clonagem Molecular , RNA Polimerases Dirigidas por DNA/genética , Mitocôndrias/enzimologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Células COS , Mapeamento Cromossômico , Cromossomos Humanos Par 19 , DNA Complementar , DNA Mitocondrial/genética , RNA Polimerases Dirigidas por DNA/química , Bases de Dados Factuais , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Expressão Gênica , Marcadores Genéticos , Testes Genéticos , Humanos , Dados de Sequência Molecular , RNA/genética , RNA Mitocondrial , Proteínas Recombinantes de Fusão , Análise de Sequência , Homologia de Sequência de Aminoácidos
13.
Arch Microbiol ; 164(4): 290-3, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7487335

RESUMO

Growth of Helicobacter pylori in liquid culture requires the addition of media supplements that often interfere with subsequent purification of bacterial antigens. In order to determine whether cyclodextrins can substitute for conventional H. pylori growth supplements, we cultured H. pylori in the presence of five commercially available cyclodextrins. The effect of these compounds on the production of the vacuolating cytotoxin antigen was evaluated. Several cyclodextrins supported flourishing growth and permitted the consistent production of vacuolating cytotoxin. These data suggest that Brucella broth supplemented with cyclodextrins is an improved medium for bacterial culture and industrial production of H. pylori antigens.


Assuntos
Proteínas de Bactérias/biossíntese , Meios de Cultura , Ciclodextrinas/farmacologia , Citotoxinas/biossíntese , Helicobacter pylori/crescimento & desenvolvimento , Antígenos de Bactérias/biossíntese , Helicobacter pylori/metabolismo , Microbiologia Industrial
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