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1.
Leukemia ; 37(5): 988-1005, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37019990

RESUMO

Chromosomal rearrangements of the human KMT2A/MLL gene are associated with de novo as well as therapy-induced infant, pediatric, and adult acute leukemias. Here, we present the data obtained from 3401 acute leukemia patients that have been analyzed between 2003 and 2022. Genomic breakpoints within the KMT2A gene and the involved translocation partner genes (TPGs) and KMT2A-partial tandem duplications (PTDs) were determined. Including the published data from the literature, a total of 107 in-frame KMT2A gene fusions have been identified so far. Further 16 rearrangements were out-of-frame fusions, 18 patients had no partner gene fused to 5'-KMT2A, two patients had a 5'-KMT2A deletion, and one ETV6::RUNX1 patient had an KMT2A insertion at the breakpoint. The seven most frequent TPGs and PTDs account for more than 90% of all recombinations of the KMT2A, 37 occur recurrently and 63 were identified so far only once. This study provides a comprehensive analysis of the KMT2A recombinome in acute leukemia patients. Besides the scientific gain of information, genomic breakpoint sequences of these patients were used to monitor minimal residual disease (MRD). Thus, this work may be directly translated from the bench to the bedside of patients and meet the clinical needs to improve patient survival.


Assuntos
Histona-Lisina N-Metiltransferase , Leucemia Mieloide Aguda , Proteína de Leucina Linfoide-Mieloide , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Leucemia Mieloide Aguda/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Histona-Lisina N-Metiltransferase/genética , Proteína de Leucina Linfoide-Mieloide/genética , Fusão Gênica
2.
Leukemia ; 32(2): 273-284, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28701730

RESUMO

Chromosomal rearrangements of the human MLL/KMT2A gene are associated with infant, pediatric, adult and therapy-induced acute leukemias. Here we present the data obtained from 2345 acute leukemia patients. Genomic breakpoints within the MLL gene and the involved translocation partner genes (TPGs) were determined and 11 novel TPGs were identified. Thus, a total of 135 different MLL rearrangements have been identified so far, of which 94 TPGs are now characterized at the molecular level. In all, 35 out of these 94 TPGs occur recurrently, but only 9 specific gene fusions account for more than 90% of all illegitimate recombinations of the MLL gene. We observed an age-dependent breakpoint shift with breakpoints localizing within MLL intron 11 associated with acute lymphoblastic leukemia and younger patients, while breakpoints in MLL intron 9 predominate in AML or older patients. The molecular characterization of MLL breakpoints suggests different etiologies in the different age groups and allows the correlation of functional domains of the MLL gene with clinical outcome. This study provides a comprehensive analysis of the MLL recombinome in acute leukemia and demonstrates that the establishment of patient-specific chromosomal fusion sites allows the design of specific PCR primers for minimal residual disease analyses for all patients.


Assuntos
Histona-Lisina N-Metiltransferase/genética , Leucemia Mieloide Aguda/genética , Proteína de Leucina Linfoide-Mieloide/genética , Adulto , Criança , Aberrações Cromossômicas , Quebra Cromossômica , Feminino , Rearranjo Gênico/genética , Humanos , Lactente , Masculino , Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocação Genética/genética
3.
Oncogene ; 35(16): 2020-30, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-26189795

RESUMO

Current treatment regimens for rhabdomyosarcoma (RMS), the most common pediatric soft tissue cancer, rely on conventional chemotherapy, and although they show clinical benefit, there is a significant risk of adverse side effects and secondary tumors later in life. Therefore, identifying and targeting sub-populations with higher tumorigenic potential and self-renewing capacity would offer improved patient management strategies. Hedgehog signaling has been linked to the development of embryonal RMS (ERMS) through mouse genetics and rare human syndromes. However, activating mutations in this pathway in sporadic RMS are rare and therefore the contribution of hedgehog signaling to oncogenesis remains unclear. Here, we show by genetic loss- and gain-of-function experiments and the use of clinically relevant small molecule modulators that hedgehog signaling is important for controlling self-renewal of a subpopulation of RMS cells in vitro and tumor initiation in vivo. In addition, hedgehog activity altered chemoresistance, motility and differentiation status. The core stem cell gene NANOG was determined to be important for ERMS self-renewal, possibly acting downstream of hedgehog signaling. Crucially, evaluating the presence of a subpopulation of tumor-propagating cells in patient biopsies identified by GLI1 and NANOG expression had prognostic significance. Hence, this work identifies novel functional aspects of hedgehog signaling in ERMS, redefines the rationale for its targeting as means to control ERMS self-renewal and underscores the importance of studying functional tumor heterogeneity in pediatric cancers.


Assuntos
Carcinogênese , Proteínas Hedgehog/metabolismo , Rabdomiossarcoma Embrionário/patologia , Transdução de Sinais , Humanos , Prognóstico , Rabdomiossarcoma Embrionário/metabolismo , Células Tumorais Cultivadas
4.
Int J Rob Res ; 29(13): 1640-1660, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21170164

RESUMO

The tip asymmetry of a bevel-tip needle results in the needle naturally bending when it is inserted into soft tissue. This enables robotic needle steering, which can be used in medical procedures to reach subsurface targets inaccessible by straight-line trajectories. However, accurate path planning and control of needle steering requires models of needle-tissue interaction. Previous kinematic models required empirical observations of each needle and tissue combination in order to fit model parameters. This study describes a mechanics-based model of robotic needle steering, which can be used to predict needle behavior and optimize system design based on fundamental mechanical and geometrical properties of the needle and tissue. We first present an analytical model for the loads developed at the tip, based on the geometry of the bevel edge and material properties of soft-tissue simulants (gels). We then present a mechanics-based model that calculates the deflection of a bevel-tipped needle inserted through a soft elastic medium. The model design is guided by microscopic observations of needle-gel interactions. The energy-based formulation incorporates tissue-specific parameters, and the geometry and material properties of the needle. Simulation results follow similar trends (deflection and radius of curvature) to those observed in experimental studies of robotic needle insertion.

5.
Oncogene ; 29(27): 3942-52, 2010 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-20453878

RESUMO

A number of drugs developed against cancer-specific molecular targets have been shown to offer survival benefits alone or in combination with standard treatments, especially for those cases in which tumor pathogenesis is dominated by a single molecular abnormality. One example for such a tumor type is alveolar rhabdomyosarcoma (aRMS), which is characterized by a specific translocation creating the oncogenic PAX3/FKHR transcription factor, believed to be the molecular basis of the disease. Recently, we were able to show that the small molecule inhibitor PKC412 (midostaurin) shows strong antitumor activity against aRMS by reducing the transcriptional activity of PAX3/FKHR. In this study, we screened for combination strategies that are superior to PKC412-only treatment and found that the combination of PKC412 with histone deacetylase inhibitors like valproic acid (VPA) synergistically induced apoptosis resulting in suppressed aRMS tumor growth in vivo. We provide evidence that the antitumor effect on combination treatment is achieved by VPA-induced reactivation of p21, which is downregulated in aRMS cells by destabilization of the transcriptional regulator EGR1 by PAX3/FKHR. Our study highlights a possible mechanism behind the increased efficacy and indicates that different arms of PAX3/FKHR oncogenicity can be exploited therapeutically by the specific combination of drugs to increase their therapeutic potential.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação para Baixo/efeitos dos fármacos , Fatores de Transcrição Forkhead/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Neoplasias/patologia , Fatores de Transcrição Box Pareados/metabolismo , Ativação Transcricional/efeitos dos fármacos , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/genética , Sinergismo Farmacológico , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genótipo , Inibidores de Histona Desacetilases/administração & dosagem , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Rabdomiossarcoma Alveolar/tratamento farmacológico , Rabdomiossarcoma Alveolar/genética , Rabdomiossarcoma Alveolar/metabolismo , Rabdomiossarcoma Alveolar/patologia , Estaurosporina/administração & dosagem , Estaurosporina/análogos & derivados , Estaurosporina/farmacologia , Estaurosporina/uso terapêutico , Ácido Valproico/administração & dosagem , Ácido Valproico/farmacologia , Ácido Valproico/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Leukemia ; 23(8): 1490-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19262598

RESUMO

Chromosomal rearrangements of the human MLL gene are associated with high-risk pediatric, adult and therapy-associated acute leukemias. These patients need to be identified, treated appropriately and minimal residual disease was monitored by quantitative PCR techniques. Genomic DNA was isolated from individual acute leukemia patients to identify and characterize chromosomal rearrangements involving the human MLL gene. A total of 760 MLL-rearranged biopsy samples obtained from 384 pediatric and 376 adult leukemia patients were characterized at the molecular level. The distribution of MLL breakpoints for clinical subtypes (acute lymphoblastic leukemia, acute myeloid leukemia, pediatric and adult) and fused translocation partner genes (TPGs) will be presented, including novel MLL fusion genes. Combined data of our study and recently published data revealed 104 different MLL rearrangements of which 64 TPGs are now characterized on the molecular level. Nine TPGs seem to be predominantly involved in genetic recombinations of MLL: AFF1/AF4, MLLT3/AF9, MLLT1/ENL, MLLT10/AF10, MLLT4/AF6, ELL, EPS15/AF1P, MLLT6/AF17 and SEPT6, respectively. Moreover, we describe for the first time the genetic network of reciprocal MLL gene fusions deriving from complex rearrangements.


Assuntos
Leucemia/genética , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas de Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Recombinação Genética , Translocação Genética , Doença Aguda , Adulto , Biópsia , Medula Óssea/química , Medula Óssea/patologia , Criança , Quebra Cromossômica , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 11/ultraestrutura , Biologia Computacional , DNA de Neoplasias/sangue , DNA de Neoplasias/genética , Duplicação Gênica , Histona-Lisina N-Metiltransferase , Humanos , Reação em Cadeia da Polimerase
7.
Leukemia ; 22(4): 771-82, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18239620

RESUMO

Detection of minimal residual disease (MRD) is the most sensitive method to evaluate treatment response and one of the strongest predictors of outcome in childhood acute lymphoblastic leukemia (ALL). The 10-year update on the I-BFM-SG MRD study 91 demonstrates stable results (event-free survival), that is, standard risk group (MRD-SR) 93%, intermediate risk group (MRD-IR) 74%, and high risk group (MRD-HR) 16%. In multicenter trial AIEOP-BFM ALL 2000, patients were stratified by MRD detection using quantitative PCR after induction (TP1) and consolidation treatment (TP2). From 1 July 2000 to 31 October 2004, PCR target identification was performed in 3341 patients: 2365 (71%) patients had two or more sensitive targets (< or =10(-4)), 671 (20%) patients revealed only one sensitive target, 217 (6%) patients had targets with lower sensitivity, and 88 (3%) patients had no targets. MRD-based risk group assignment was feasible in 2594 (78%) patients: 40% were classified as MRD-SR (two sensitive targets, MRD negativity at both time points), 8% as MRD-HR (MRD > or =10(-3) at TP2), and 52% as MRD-IR. The remaining 823 patients were stratified according to clinical risk features: HR (n=108) and IR (n=715). In conclusion, MRD-PCR-based stratification using stringent criteria is feasible in almost 80% of patients in an international multicenter trial.


Assuntos
Rearranjo Gênico , Neoplasia Residual , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adolescente , Criança , Pré-Escolar , Rearranjo Gênico do Linfócito T , Genes de Imunoglobulinas/genética , Humanos , Lactente , Reação em Cadeia da Polimerase , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Medição de Risco
8.
Oncogene ; 26(51): 7267-81, 2007 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-17525748

RESUMO

The chromosomal translocation t(2;13), characteristic for the aggressive childhood cancer alveolar rhabdomyosarcoma (aRMS), generates the chimeric transcription factor PAX3/FKHR with a well known oncogenic role. However, the molecular mechanisms mediating essential pathophysiological functions remain poorly defined. Here, we used comparative expression profiling of PAX3/FKHR silencing in vitro and PAX3/FKHR-specific gene signatures in vivo to identify physiologically important target genes. Hereby, 51 activated genes, both novel and known, were identified. We also found repression of skeletal muscle-specific genes suggesting that PAX3/FKHR blocks further differentiation of aRMS cells. Importantly, TFAP2B was validated as direct target gene mediating the anti-apoptotic function of PAX3/FKHR. Hence, we developed a pathophysiologically relevant transcriptional profile of PAX3/FKHR and identified a critical target gene for aRMS development.


Assuntos
Sobrevivência Celular/fisiologia , Fatores de Transcrição Forkhead/fisiologia , Perfilação da Expressão Gênica , Fatores de Transcrição Box Pareados/fisiologia , Fator de Transcrição AP-2/fisiologia , Proteína Forkhead Box O1 , Humanos , Fator de Transcrição PAX3
9.
Oncogene ; 25(40): 5475-84, 2006 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-16652157

RESUMO

The E1A-targeted transcription factor E4F1 is a key player in the control of mammalian embryonic and somatic cell proliferation and survival. Mouse embryos lacking E4F die at an early developmental stage, whereas enforced expression of E4F1 in various cell lines inhibits cell cycle progression. E4F1-antiproliferative effects have been shown to depend on its capacity to repress transcription and to interact with pRb and p53. Here we show that full-length E4F1 protein (p120(E4F1)) but not its E1A-activated and truncated form (p50(E4F1)), interacts directly in vitro and in vivo with the LIM-only protein FHL2, the product of the p53-responsive gene FHL2/DRAL (downregulated in rhabdomyosarcoma Lim protein). This E4F1-FHL2 association occurs in the nuclear compartment and inhibits the capacity of E4F1 to block cell proliferation. Consistent with this effect, ectopic expression of FHL2 inhibits E4F1 repressive effects on transcription and correlates with a reduction of nuclear E4F1-p53 complexes. Overall, these results suggest that FHL2/DRAL is an inhibitor of E4F1 activity. Finally, we show that endogenous E4F1-FHL2 complexes form in U2OS cells upon UV-light-induced nuclear accumulation of FHL2.


Assuntos
Proteínas de Homeodomínio/metabolismo , Proteínas Musculares/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Transporte Ativo do Núcleo Celular , Proteínas E4 de Adenovirus/metabolismo , Animais , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Humanos , Proteínas com Homeodomínio LIM , Camundongos , Células NIH 3T3 , Ligação Proteica , Proteínas Repressoras/química , Transdução de Sinais , Fatores de Transcrição/química , Transcrição Gênica , Transfecção , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases , Raios Ultravioleta
10.
Leukemia ; 20(5): 777-84, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16511515

RESUMO

Chromosomal rearrangements of the human MLL gene are a hallmark for aggressive (high-risk) pediatric, adult and therapy-associated acute leukemias. These patients need to be identified in order to subject these patients to appropriate therapy regimen. A recently developed long-distance inverse PCR method was applied to genomic DNA isolated from individual acute leukemia patients in order to identify chromosomal rearrangements of the human MLL gene. We present data of the molecular characterization of 414 samples obtained from 272 pediatric and 142 adult leukemia patients. The precise localization of genomic breakpoints within the MLL gene and the involved translocation partner genes (TPGs) was determined and several new TPGs were identified. The combined data of our study and published data revealed a total of 87 different MLL rearrangements of which 51 TPGs are now characterized at the molecular level. Interestingly, the four most frequently found TPGs (AF4, AF9, ENL and AF10) encode nuclear proteins that are part of a protein network involved in histone H3K79 methylation. Thus, translocations of the MLL gene, by itself coding for a histone H3K4 methyltransferase, are presumably not randomly chosen, rather functionally selected.


Assuntos
Leucemia/genética , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas de Fusão Oncogênica/genética , Translocação Genética/genética , Doença Aguda , Adulto , Criança , Aberrações Cromossômicas , Mapeamento Cromossômico , DNA/genética , DNA/isolamento & purificação , Histona-Lisina N-Metiltransferase , Histonas/metabolismo , Humanos , Metilação
11.
Leukemia ; 18(10): 1624-9, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15356660

RESUMO

Several studies involving identical twins with concordant leukemia and retrospective scrutiny of archived neonatal blood spots have shown that the TEL-AML1 fusion gene in childhood acute lymphoblastic leukemia (ALL) frequently arises before birth. A prenatal origin of childhood leukemia was further supported by the detection of clonotypic immunoglobulin gene rearrangements on neonatal blood spots of children with various other subtypes of ALL. However, no comprehensive study is available linking these clonotypic events. We describe a pair of 5-year-old monozygotic twins with concordant TEL-AML1-positive ALL. Separate leukemic clones were identified in the diagnostic samples since distinct IGH and IGK-Kde gene rearrangements could be detected. Additional differences characterizing the leukemic clones included an aberration of the second, nonrearranged TEL allele observed in one twin only. Interestingly, both the identical TEL-AML1 fusion sequence and distinct immunoglobulin gene rearrangements were identified on the neonatal blood spots indicating that separate preleukemic clones evolved already before birth. Finally, we compared the reported twins with an additional 31 children with ALL by using the microarray technology. Gene expression profiling provided evidence that leukemia in twins harbours the same subtype-typical feature as TEL-AML1-positive leukemia in singletons suggesting that the leukemogenesis model might also be applicable generally.


Assuntos
Doenças em Gêmeos/genética , Rearranjo Gênico , Genes de Imunoglobulinas , Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Gêmeos Monozigóticos , Sequência de Bases , Pré-Escolar , Subunidade alfa 2 de Fator de Ligação ao Core , Feminino , Perfilação da Expressão Gênica , Humanos , Hibridização in Situ Fluorescente , Dados de Sequência Molecular , Filogenia , Leucemia-Linfoma Linfoblástico de Células Precursoras/embriologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Homologia de Sequência do Ácido Nucleico
12.
Histol Histopathol ; 17(1): 123-30, 2002 01.
Artigo em Inglês | MEDLINE | ID: mdl-11813862

RESUMO

It has been previously shown that S100A2 is downregulated in tumor cells. The level of immunohistochemical S100A2 expression was therefore characterized in 424 normal and tumoral (benign and malignant) tissues of various origins, but mostly epithelial (with either glandular, squamous, respiratory or urothelial differentiation). We also investigated whether S100A2 could be co-localized with cytokeratin K14, an intermediate filament protein expressed in basal proliferative keratinocytes. Our data show that S100A2 has a low level of expression in non-epithelial tissue. In epithelial tissue S100A2 expression decreases remarkably in the tumors when compared to the normal specimens, and was correlated with the level of keratin K14. This decrease in S100A2 staining from normal to cancer cases is more pronounced in glandular than in squamous epithelial tissue. In addition, the patterns of S100A2 staining also differ between glandular and squamous tissue. These data suggest distinct functional roles for S100A2 in epithelial tissue of squamous or glandular origins.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Fatores Quimiotáticos/biossíntese , Células Epiteliais/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias Epiteliais e Glandulares/metabolismo , Proteínas S100/biossíntese , Carcinoma de Células Escamosas/genética , Fatores Quimiotáticos/genética , Citoplasma/metabolismo , Neoplasias de Cabeça e Pescoço/genética , Humanos , Imuno-Histoquímica , Queratinas/metabolismo , Neoplasias Epiteliais e Glandulares/genética , Inclusão em Parafina , Proteínas S100/genética , Fixação de Tecidos
13.
Biochem Biophys Res Commun ; 288(2): 462-7, 2001 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-11606065

RESUMO

The S100 subfamily of EF-hand proteins is distinguished by the binding of Zn(2+) in addition to Ca(2+). In an effort to understand the role of Zn(2+) in modulating the activity of S100 proteins, we have carried out heteronuclear NMR studies of Zn(2+)-bound S100A2 and obtained near complete resonance assignments. This analysis revealed an equilibrium between multiple isoforms due to cis-trans isomerism of proline residues in flexible regions of the protein. The secondary structure of S100A2 has been determined based on the NMR chemical shift index (CSI) technique. The protein is found to possess essentially the same secondary structure found in other S100 proteins such as S100A6 and S100B. Homology models have been built based on the high resolution three-dimensional structures of other S100 proteins. The models predict two Zn(2+) binding clusters, one involving residues His17-Cys21-Cys93 and the other Cys2-His39, and with Cys86 participating in either the N-terminal or the C-terminal binding site.


Assuntos
Proteínas de Ciclo Celular , Fatores Quimiotáticos/química , Proteínas S100/química , Zinco/química , Proteínas de Ligação ao Cálcio/química , Proteínas de Transporte/química , Humanos , Espectroscopia de Ressonância Magnética/métodos , Modelos Moleculares , Fatores de Crescimento Neural/química , Conformação Proteica , Reprodutibilidade dos Testes , Proteína A6 Ligante de Cálcio S100 , Proteína A7 Ligante de Cálcio S100 , Subunidade beta da Proteína Ligante de Cálcio S100 , Homologia de Sequência de Aminoácidos
14.
Histol Histopathol ; 16(3): 707-12, 2001 07.
Artigo em Inglês | MEDLINE | ID: mdl-11510959

RESUMO

The expression levels of seven different S100 proteins (S100A1, S100A2, S100A3, S100A4, S100A5, S100A6, and S100B) were characterized by immunohistochemistry in the epithelial versus connective tissues of a series of 35 colon specimens, including 6 normal samples, 5 adenomas with low-grade dysplasia, 5 adenomas with high-grade dysplasia, and 19 cancers. The results showed that S100A2, S100A3, and S100B proteins could not (or only marginally) be detected in colon tissues. On the other hand, the expression of S100A6 increased in epithelial tissues directly proportional to the increase of malignancy. The percentage of epithelial (or connective tissue) cells expressing S100A4 significantly decreased as the malignancy grade increased. The expression level of S100A1 proteins was somewhat higher in the connective tissues of normal cases and adenomas with low-grade dysplasia than in adenomas with high-grade dysplasia and cancers. This pattern of expression was not observed in epithelial tissues. While the node-positive cancers did not express S100A1, about half of the node-negative specimens did. The expression levels of S100A5 were similar in different epithelial tissues. However, in the connective tissues the expression levels decreased inversely proportional to the increase in pathological grading of the specimens. Therefore, the present study implicates several S100 proteins as useful tools for histochemical typing of colon cancer malignancy development.


Assuntos
Proteínas de Ciclo Celular , Colo/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Proteínas S100/metabolismo , Adenoma/etiologia , Adenoma/metabolismo , Adenoma/patologia , Proteínas de Ligação ao Cálcio/metabolismo , Fatores Quimiotáticos/metabolismo , Neoplasias do Colo/etiologia , Humanos , Imuno-Histoquímica , Fatores de Crescimento Neural/metabolismo , Prognóstico , Proteína A6 Ligante de Cálcio S100 , Subunidade beta da Proteína Ligante de Cálcio S100 , Proteína A4 de Ligação a Cálcio da Família S100
15.
Lab Invest ; 81(4): 599-612, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11304580

RESUMO

It has been previously shown that S100A2 is down-regulated in tumor cells and can be considered a tumor suppressor. We have recently shown that this down-regulation can be observed particularly in epithelial tissue, where S100A2 expression decreases remarkably in tumors as compared with normal specimens. In the present paper we investigate whether S100A2 could play a tumor-suppressor role in certain epithelial tissues by acting at the cell migration level. To this end, we made use of five in vitro human head and neck squamous cell carcinoma lines in which we characterized S100A2 expression at both RNA and protein level. To characterize the influence of S100A2 on cell kinetic and cell motility features, we used two complementary approaches involving specific antisense oligonucleotides and the addition of S100A2 to the culture media. The different expression analyses gave a coherent demonstration of the fact that the FADU and the RPMI-2650 cell lines exhibit high and low levels of S100A2 expression, respectively. Antisense oligonucleotides (in FADU) and extracellular treatments (in RPMI) showed that, for these two models, S100A2 had a clear inhibitory influence on cell motility while modifying the cell kinetic parameters only slightly. These effects seem to be related, at least in part, to a modification in the polymerization/depolymerization dynamics of the actin microfilamentary cytoskeleton. Furthermore, we found evidence of the presence of the receptor for advanced glycation end-products (RAGE) in RPMI cells, which may act as a receptor for extracellular S100A2. The present study therefore presents experimentally based evidence showing that S100A2 could play a tumor-suppressor role in certain epithelial tissues by restraining cell migration features, at least in the case of head and neck squamous cell carcinomas.


Assuntos
Carcinoma de Células Escamosas/patologia , Movimento Celular , Fatores Quimiotáticos/fisiologia , Neoplasias de Cabeça e Pescoço/patologia , Proteínas S100/fisiologia , Actinas/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Fatores Quimiotáticos/genética , Fatores Quimiotáticos/metabolismo , Regulação para Baixo , Genes Supressores de Tumor , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Cinética , Oligonucleotídeos Antissenso/farmacologia , Polímeros/metabolismo , RNA Mensageiro/biossíntese , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Proteínas S100/genética , Proteínas S100/metabolismo , Células Tumorais Cultivadas
16.
Int J Oncol ; 18(4): 715-20, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11251165

RESUMO

S100A4 has been implicated in invasion and metastasis of cancer, but prognostic significance of its expression in esophageal squamous cell carcinoma remains unclear. In this study, we examined the expression of S100A4 by Western blot analysis and immunohistochemistry in surgically resected esophageal squamous cell carcinoma. The relationship between S100A4 tissue status and clinicopathological findings was analyzed to assess the prognostic significance of S100A4 in esophageal squamous cell carcinoma. The S100A4 protein level was significantly higher in tumor tissue than in corresponding normal esophageal mucosa (p<0.05) in 22 cases of esophageal carcinoma by Western blot analysis. S100A4 expression was detected in 25% of 52 cases of esophageal squamous cell carcinoma by immunohistochemistry and correlated with the depth of invasion (p<0.05). Patients with S100A4-positive carcinoma had significantly poorer prognosis than those with S100A4-negative carcinoma, which was also true in the cases with deep invasion of the primary cancer (T3, T4) (p<0.01 and p<0.05, respectively). Moreover, S100A4 tissue status remained the only independent prognostic parameter in the multivariate analysis. Our results suggest that S100A4 may play a key role in the progression of esophageal carcinoma and that immunohistochemical detection of S100A4 in the primary tumor may be useful for the prediction of a poor prognosis.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , Proteínas S100/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Prognóstico , Proteína A4 de Ligação a Cálcio da Família S100 , Taxa de Sobrevida
17.
Brain Res Dev Brain Res ; 126(2): 191-9, 2001 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-11248353

RESUMO

The immunolocalization of three members of the S100 calcium-binding protein family was investigated in the dog cochlea during normal postnatal development. Sections of decalcified and paraffin-embedded cochleae from 16 beagle puppies aged from birth to 3 months were treated with polyclonal antisera raised against the human recombinant S100A1, S100A5, and S100A6 proteins. At birth, in the dog cochlea, S100A1 was expressed in the immature Deiter's cells, and slightly in the pillar cells. From the second week, S100A1 was detected in the supporting structures of the organ of Corti, i.e. the Deiter's, the pillar, the border, and the Hensen's cells, and in the reticular membrane. From birth onwards, S100A5 remained a neuronal-specific protein, only located in a subpopulation of neurons in the spiral ganglion. S100A6 was not expressed at birth. From the second week of life, the Schwann cells and nerve sheaths in the modiolus, in the spiral ganglion, and running in the direction of the organ of Corti exhibited S100A6-labeling. From the 12th postnatal day, some scattered intermediate cells started to express S100A6 protein in the stria vascularis. The number of labeled intermediate cells increased during the third week. At adult stage, the intermediate cells were S100A6-stained with cytoplasmic labeling throughout the stria vascularis from the base to the apex of the cochlea. None of the other cochlear structures expressed the S100 proteins under study during the postnatal development of the dog cochlea. The S100A1, S100A5, S100A6 immunostaining was limited to specific cell types in dog cochlea. These S100 proteins were useful markers in the study of supporting cells, neurons, nerve fibers sheaths and stria vascularis (S100A6) during the normal postnatal development of the dog cochlea.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Cóclea/crescimento & desenvolvimento , Cóclea/metabolismo , Proteínas S100/metabolismo , Animais , Animais Recém-Nascidos , Cóclea/citologia , Cães , Feminino , Imuno-Histoquímica , Masculino , Especificidade de Órgãos , Gânglio Espiral da Cóclea/citologia , Gânglio Espiral da Cóclea/crescimento & desenvolvimento , Gânglio Espiral da Cóclea/metabolismo , Estria Vascular/citologia , Estria Vascular/metabolismo
18.
Cancer Res ; 61(3): 823-6, 2001 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-11221862

RESUMO

Deregulated expression of the transcription factor PAX3 was observed previously in several tumors like rhabdomyosarcoma and Ewing's sarcoma. Because PAX3 expression is also found in pluripotent neural crest cells, we investigated whether melanomas, tumors derived mostly from cutaneous intraepidermal melanocytes, might show deregulated PAX3 expression. Using a specific and sensitive reverse transcription-PCR, we detected PAX3 mRNA in 77% (27 of 35) of primary cultured melanomas. These results could be confirmed by direct in situ hybridization on the corresponding tissue sections where PAX3 expression was unambiguously confined to tumor cells and not detected in surrounding normal tissue, normal skin sections, or sections of benign lesions. Furthermore, down-regulation of PAX3 expression achieved through a specific antisense oligonucleotide-based treatment resulted in > 70% of dead cells specifically in PAX3-positive melanomas. Annexin V staining confirmed that primary melanoma cells underwent apoptosis after treatment These experiments suggest that in situ hybridization of PAX3 on paraffin-embedded tissue may represent a novel means to identify melanoma cell lesions, which appear to become dependent on expression of this deregulated transcription factor.


Assuntos
Proteínas de Ligação a DNA/biossíntese , Melanoma/metabolismo , Melanoma/patologia , Fatores de Transcrição , Sobrevivência Celular/fisiologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/fisiologia , Regulação Neoplásica da Expressão Gênica , Humanos , Hibridização In Situ , Melanoma/genética , Estadiamento de Neoplasias , Fator de Transcrição PAX3 , Fatores de Transcrição Box Pareados , Inclusão em Parafina , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
19.
Physiol Res ; 50(6): 567-74, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11829317

RESUMO

Impaired calcium homeostasis and altered expression of Ca2+-binding proteins are associated with cardiomyopathies, myocardial hypertrophy, infarction or ischemia. S100A1 protein with its modulatory effect on different target proteins has been proposed as one of potential candidates which could participate in these pathological processes. The exact localization of S100A1 in human heart cells on the ultrastructural level accompanied with biochemical determination of its target proteins may help clarify the role of S100A1 in heart muscle. In the present study the distribution of the S100A1 protein using postembedding (Lowicryl K4M) immunocytochemical method in human heart muscle has been determined quantitatively, relating number of antigen sites to the unit area of a respective structural component. S100A1 antigen sites have been detected in elements of sarcoplasmic reticulum (SR), in myofibrils at all levels of sarcomere and in mitochondria, the density of immunolabeling at Z-lines being about 3 times and at SR more than 5 times higher than immunolabeling of remaining structural components. The presence of the S100A1 in SR and myofibrils may be related to the known target proteins for S100A1 at these sites.


Assuntos
Proteínas de Ligação ao Cálcio/análise , Miocárdio/química , Adulto , Humanos , Imuno-Histoquímica , Masculino , Microscopia Imunoeletrônica , Miocárdio/ultraestrutura , Miofibrilas/química , Miofibrilas/ultraestrutura , Proteínas S100 , Sarcômeros/química , Sarcômeros/ultraestrutura
20.
Clin Cancer Res ; 6(11): 4234-42, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11106237

RESUMO

S100A4 is known to be involved in cancer cell motility by virtue of its ability to activate nonmuscle myosin. E-cadherin has an important role in the homophilic cell-cell adhesion and is called an invasion suppressor gene. In the current study, we investigate the histological type and metastatic potential of gastric cancer from the aspect of the interrelationship of E-cadherin and S100A4 expression. Expression of E-cadherin and S100A4 in gastric cancer cell lines, primary gastric cancers, and their normal counterparts were analyzed by reverse transcription-PCR, Western blot, and immunohistochemical methods. S100A4 protein and E-cadherin were expressed in five of eight gastric cancer cell lines, and inverse expression of the two proteins are found in four cell lines. In the clinical specimens, E-cadherin mRNA expression in differentiated adenocarcinomas (88%, 14 of 16) was significantly more frequent than that in poorly differentiated adenocarcinomas (50%, 22 of 44; P = 0.015). Western blot analysis demonstrates that S100A4 protein expression in poorly differentiated adenocarcinomas was 1.6-fold higher than in well differentiated adenocarcinoma. Immunohistochemically, S100A4 expression was detected in 51 (55%) of 92 primary gastric cancers. Reduced expression of E-cadherin in primary tumors was found in 66 (72%) of 92 tumors. S100A4 expression in the poorly differentiated adenocarcinomas had a strong relation to positive lymph node involvement or peritoneal dissemination. Reduced E-cadherin expression showed a strong relationship with positive serosal involvement and infiltrating type. Tumors classified as a group with reduced E-cadherin and high expression of S100A4 reveal positive peritoneal dissemination, serosal involvement, and infiltrating type in the growth pattern. Furthermore, these tumors showed a strong correlation with the poorly differentiated adenocarcinoma. In contrast, tumors with preserved E-cadherin and low expression of S100A4 have a close relation to the well differentiated adenocarcinoma and a favorable prognosis. By the Cox proportional hazard model, S100A4 and E-cadherin tissue status was judged as an independent prognostic factor. S100A4 and E-cadherin tissue status may be a powerful aid in evaluating metastatic potential or the prognosis of patients with gastric cancer.


Assuntos
Caderinas/análise , Proteínas S100/análise , Neoplasias Gástricas/patologia , Caderinas/genética , Humanos , Metástase Neoplásica , Prognóstico , RNA Mensageiro/análise , Proteína A4 de Ligação a Cálcio da Família S100 , Proteínas S100/genética , Neoplasias Gástricas/química , Neoplasias Gástricas/mortalidade , Células Tumorais Cultivadas
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