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2.
Urologiia ; (5): 30-3, 2002.
Artigo em Russo | MEDLINE | ID: mdl-12402773

RESUMO

Three-component (cyclosporin A, corticosteroids and azathioprine) immunosuppression has been widely introduced in the treatment of recipients of renal transplants because it allows a significant reduction of the components' doses in greater effectiveness. The analysis of the results of 83 puncture biopsies obtained in the immediate postoperative period after kidney transplantation has shown that administration of an imidazole derivative allows raising therapeutic concentration of cyclosporin up to 200-300 ng/ml, thus preventing rejection crises. However, increased blood concentration of cyclosporin does not increase its toxicity as a result of a significant fall in the overall level of the metabolites.


Assuntos
Terapia de Imunossupressão/métodos , Imunossupressores/uso terapêutico , Transplante de Rim , Período Pós-Operatório , Corticosteroides/administração & dosagem , Corticosteroides/uso terapêutico , Azatioprina/administração & dosagem , Azatioprina/uso terapêutico , Ciclosporina/administração & dosagem , Ciclosporina/uso terapêutico , Quimioterapia Combinada , Humanos , Imuno-Histoquímica , Imunossupressores/administração & dosagem
3.
Leuk Res ; 25(11): 981-95, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11597733

RESUMO

Human C/EBPepsilon is a recently cloned member of the C/EBP family of transcriptional factors. Previous studies demonstrated that the expression of this gene is tightly regulated in a tissue-specific manner; it is expressed almost exclusively in myeloid cells. To understand the mechanism by which the expression of C/EBPepsilon gene is controlled, we cloned a large genomic region surrounding the C/EBPepsilon gene and performed a DNase I hypersensitivity analysis of this locus. These sites probably represent areas of binding of proteins modulating gene transcription. Hypersensitive (HS) regions in 30 kb of DNA surrounding the C/EBPepsilon gene were examined in C/EBPepsilon high-expressing (NB4, HL-60), low-expressing (Jurkat), very-low-expressing (KG-1), and non-expressing (K562) hematopoietic cells as well as in non-hematopoietic-non-expressing cells (MCF-7, DU 145, PC-3). Three HS sites were detected near the first exon of C/EBPepsilon gene. They were found only in hematopoietic cells and were especially prominent in C/EBPepsilon expressing cells, suggesting that these sites play an important role in transcribing the gene. These hypersensitive bands did not change when the cells were cultured with retinoids. Gel-shift assays using 200 bp of nucleotide sequences that encompassed the hypersensitive sites and nuclear extracts from NB4 and Jurkat cells (C/EBPepsilon expressing) as well as K562 and MCF-7 cells (non-expressing) showed different retarded bands on gel electrophoresis. A fourth HS site, located about 11 kb upstream of exon 1, was found only in cells highly expressing C/EBPepsilon. Two sites, one about 4.5 kb upstream of exon 1 and another about 8.5 kb downstream of exon 2, were positive only in non-expressing cell lines, suggesting that repressors may bind in these areas. Taken together, we have found six specific DNase I hypersensitive sites in the region of C/EBPepsilon that may be involved in regulating transcription of this gene.


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/genética , Desoxirribonuclease I/imunologia , Desoxirribonuclease I/metabolismo , Hipersensibilidade a Drogas/metabolismo , Alitretinoína , Antineoplásicos/farmacologia , Sítios de Ligação , Clonagem Molecular , Ensaio de Desvio de Mobilidade Eletroforética , Regulação da Expressão Gênica , Genes Reguladores , Humanos , Transcrição Gênica , Tretinoína/farmacologia , Células Tumorais Cultivadas
4.
Bull Exp Biol Med ; 132(5): 1096-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11865331

RESUMO

The intensity of ascorbate-dependent free radical oxidation of endogenous lipids in malignant tumor tissue of human kidneys was studied. The LPO induction period was markedly increased in renal-cell carcinoma and malignant mesenchymal tumors compared to normal renal cortex. The content of alpha-tocopherol in cancer tissue lipids was considerably (7-fold) increased compared to that in normal renal cortex, which explains high antioxidant activity of these carcinomas. A less pronounced increase in the content of alpha -tocopherol in lipids of malignant mesenchymal tumors compared to the cortex (2-fold) can also contribute to their LPO resistance.


Assuntos
Neoplasias Renais/metabolismo , Peroxidação de Lipídeos , Adulto , Antioxidantes/farmacologia , Ácido Ascórbico/metabolismo , Carcinoma de Células Renais/metabolismo , Ácidos Graxos Insaturados/metabolismo , Feminino , Radicais Livres , Humanos , Córtex Renal/metabolismo , Cinética , Metabolismo dos Lipídeos , Masculino , Mesoderma/metabolismo , Pessoa de Meia-Idade , Fatores de Tempo , alfa-Tocoferol/metabolismo
5.
Blood ; 96(12): 3953-7, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11090083

RESUMO

C/EBP epsilon is a recently cloned member of the C/EBP family of transcriptional factors. Previous studies demonstrated that the expression of this gene is tightly regulated in a tissue specific manner; it is expressed exclusively in myeloid cells. C/EBP epsilon-deficient mice developed normally but failed to generate functional neutrophils and eosinophils, and these mice died of opportunistic infections suggesting that C/EBP epsilon may play a central role in myeloid differentiation. To identify myelomonocytic genes regulated by the C/EBP epsilon gene, we performed representational difference analysis (RDA), a polymerase chain reaction (PCR)-based subtractive hybridization using neutrophils and macrophages from wild-type and C/EBP epsilon knockout mice. We identified a set of differentially expressed genes, including chemokines specific to myelomonocytic cells. Several novel genes were identified that were differentially expressed in normal myelomonocytic cells. Taken together, we have found several genes whose expression might be enhanced by C/EBP epsilon. (Blood. 2000;96:3953-3957)


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/farmacologia , Animais , Líquido Ascítico/citologia , Líquido Ascítico/genética , Northern Blotting , Quimiocinas/genética , Camundongos , Camundongos Knockout , Lavagem Peritoneal , RNA/efeitos dos fármacos , RNA/metabolismo , Tioglicolatos/farmacologia , Fatores de Transcrição/genética
6.
Int J Oncol ; 16(2): 401-11, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10639585

RESUMO

Myeloperoxidase (MPO) is a granule protein, transiently expressed during the promyelocyte stage of myeloid differentiation. It is transcribed in a stage and lineage specific manner. Studies of MPO gene regulation can help to elucidate the mechanism of normal and abnormal myeloid differentiation. Our preliminary data indicated the lack of basal promoter activity in the region immediately 5' to the MPO cDNA. Here, we report the results of the detailed molecular studies of the human MPO promoter region. To locate potential promoter elements active in HL60 cells, we made promoter deletion constructs ranging in size from 200 bp to 4.5 kb of the 5' region of the hMPO gene, cloned into the chloramphenicol acetyl transferase (CAT) reporter vector. Following electroporation of the promoter constructs into HL60 cells, CAT enzyme production was found only in the construct containing approximately the 1 kb region upstream of the reported MPO cDNA. A separate set of constructs was made to look for putative MPO enhancer elements. Several fragments upstream of the MPO promoter showed prominent transactivation of the TK promoter, indicating a possible enhancer. Tissue specificity of MPO promoter fragments was determined in myeloid cells arrested either before induction of MPO expression (KG1), during MPO expression (HL60), or after it had ceased (U937), as well as in non-MPO expressing non-myeloid cells. The construct containing an approximate 1000 bp fragment of the 5' region of MPO was found to direct CAT expression only in HL60 cells. The 3'-truncations of this promoter region resulted in loss of tissue-specificity, while the promoter activity remained largely unchanged. A negative regulatory element was found upstream of the MPO promoter which repressed heterologous promoters in all the tested cell lines. Enhancer elements showed no tissue- or stage-specificity that were characteristic for native MPO gene. Sequence analysis of the putative MPO promoter region showed a number of potential transcription factor binding sites. Of special interest is the region containing the purine-rich site that can bind proteins from the ets-family of transcription factors and a duplicate GATA-like site. When inserted upstream of a reporter containing the minimal Herpes simplex viral thymidine kinase (HSV-TK) promoter (into pBL2CAT plasmid) this site strongly activated the TK promoter in transfected myeloid cells. Further studies showed that oligonucleotides derived from the MPO promoter region bind multiple proteins in a band-shift assay. Taken together, our experiments located the regulatory elements important for human MPO gene expression in HL60 promyelocytes.


Assuntos
Expressão Gênica/genética , Granulócitos/metabolismo , Peroxidase/genética , Regiões Promotoras Genéticas/genética , Animais , Sequência de Bases , Gatos , Genes Reguladores/genética , Genes Reporter/genética , Células HL-60 , Humanos , Dados de Sequência Molecular , Transfecção
7.
Urologiia ; (1): 3-5, 2000.
Artigo em Russo | MEDLINE | ID: mdl-16856451

RESUMO

Chronic cystitis was diagnosed in 36% of children with neuromuscular ureteral dysplasia, in 69% of those with vesicoureteral reflux, in 42% of girls with urolithiasis. Recurrent inflammation was registered in 96, 11% of patients with fibrinous cystitis and catarrhal cystitis, respectively, and in 62% of girls with bullous cystitis. Histological examination of 130 biopsies of bladder mucosa from girls with frequent recurrences of chronic cystitis provided a clear morphological picture of each endoscopic cystitis form. In bullous cystitis there are 2 congenital variants of mucosal structure: overdevelopment of lymphoid tissue as massive lymphoid follicules and lymphangioectatic form. Catarrhal cystitis is characterized by vascular angiomatosis. All the patients with fibrinous cystitis had squamous cell epithelial metaplasia. Morphological findings evidence that fibrinous cystitis is the most severe and unfavorable form of cystitis, bullous cystitis is less severe while catarrhal cystitis is favorable.


Assuntos
Cistite/patologia , Bexiga Urinária/patologia , Adolescente , Criança , Pré-Escolar , Doença Crônica , Cistite/classificação , Cistite/etiologia , Endoscopia , Feminino , Humanos , Lactente , Recidiva
8.
J Clin Invest ; 103(10): 1399-408, 1999 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10330422

RESUMO

The CCAAT/enhancer binding protein epsilon (C/EBPepsilon) is a nuclear transcription factor expressed predominantly in myeloid cells and implicated as a potential regulator of myeloid differentiation. We show that it was rapidly induced in the acute promyelocytic leukemia (APL) cell line NB4 during granulocytic differentiation after exposure to retinoic acid (RA). Our data suggest that induction of C/EBPepsilon expression was through the retinoic acid receptor alpha (RARalpha) pathway. Reporter gene studies showed that C/EBPepsilon promoter/enhancer activity increased in a retinoid-dependent fashion via the retinoic acid response element (RARE) present in the promoter region of C/EBPepsilon. The RA-induced expression of C/EBPepsilon markedly increased in U937 myelomonoblasts that were induced to express promyelocytic leukemia/RARalpha (PML/RARalpha), but not in those induced to express promyelocytic leukemia zinc finger/RARalpha (PLZF/RARalpha). In retinoid-resistant APL cell lines, C/EBPepsilon either is not induced or is induced only at very high concentrations of RA (>/=10(-6) M). In addition, forced expression of C/EBPepsilon in the U937 myelomonoblastic leukemia cells mimicked terminal granulocytic differentiation, including morphologic changes, increased CD11b/CD66b expression, and induction of secondary granule protein expression. Our data strongly suggest that C/EBPepsilon is a downstream target gene responsible for RA-induced granulocytic differentiation of APL cells.


Assuntos
Proteínas de Ligação a DNA/genética , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/genética , Proteínas Nucleares/genética , Retinoides/uso terapêutico , Proteínas Estimuladoras de Ligação a CCAAT , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Resistência a Medicamentos/genética , Elementos Facilitadores Genéticos , Expressão Gênica/efeitos dos fármacos , Genes Reporter , Humanos , Leucemia Promielocítica Aguda/metabolismo , Regiões Promotoras Genéticas , Receptores do Ácido Retinoico/metabolismo , Receptor alfa de Ácido Retinoico , Tretinoína/farmacologia , Células Tumorais Cultivadas , Células U937
9.
Blood ; 93(10): 3327-37, 1999 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10233885

RESUMO

C/EBPepsilon is essential for granulocytic differentiation. We investigated the role of C/EBPepsilon in the transcriptional activation of various myeloid-specific genes. We found that two C/EBPepsilon isoforms, p32 and p30, possessing transcriptional activation domains were coexpressed in myeloid cells. Interestingly, isoform C/EBPepsilon p30 but not p32 was differentially upregulated in NB-4 promyelocytic leukemia cells treated with retinoids. Both isoforms bound specifically to C/EBP sites in myeloid promoters. The kd for C/EBPepsilon binding to the C/EBP site of the neutrophil elastase promoter was 4.2 nmol/L. In transfection assays using the nonhematopoietic cell line, CV-1, the p32 isoform activated promoters from the myeloid-specific mim-1, neutrophil elastase, and granulocyte colony-stimulating factor (G-CSF) receptor genes by 2.5-, 1.8-, and 1.6-fold, respectively. The p30 isoform lacked significant transcriptional activity, suggesting that other hematopoietic-specific factors were required for its function. Consistent with this prediction, transfections into the hematopoietic cell line Jurkat showed a 9.0- and 2.5-fold activation of the mim-1 promoter by the p32 and p30 isoforms, respectively. The additional 32 NH2-terminal residues made p32 a significantly more potent transcriptional activator than p30. T lymphoblasts (Jurkat cells) and immature myeloid cells (eg, Kcl22 cells) expressed high levels of the c-myb hematopoietic transcription factor. Cotransfection of c-myb with either the p32 or p30 isoform of C/EBPepsilon in CV-1 cells cooperatively transactivated the mim-1 promoter by 20- and 16-fold, respectively, and the neutrophil elastase promoter by 10-and 7-fold, respectively. Pulldown assays showed that each C/EBPepsilon isoform interacted directly with the DNA binding domain of the c-myb protein. Further studies showed that Kcl22 myeloid cells only contained active C/EBPepsilon, but not C/EBPalpha, C/EBPbeta, or C/EBPdelta. A mutation of the C/EBP site in the neutrophil elastase promoter markedly decreased the transactivation of the promoter in Kcl22 myeloblasts. These results demonstrate a role for C/EBPepsilon in regulating myeloid promoters, such as neutrophil elastase, probably through a direct interaction with c-myb.


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT , Hematopoese/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica , Animais , Sítios de Ligação , Células COS , Núcleo Celular/metabolismo , Clonagem Molecular , Proteínas de Ligação a DNA/metabolismo , Genes Reporter , Humanos , Células Jurkat , Elastase de Leucócito/genética , Camundongos , Oncogenes , Biossíntese de Proteínas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-myb , Proteínas Recombinantes de Fusão/biossíntese , Ativação Transcricional , Transfecção , Células U937
10.
J Biol Chem ; 273(24): 14796-804, 1998 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-9614080

RESUMO

Human CCAAT/enhancer-binding protein epsilon (C/EBPepsilon), a new member of the C/EBP family, significantly up-regulates both the mim-1 and human myeloperoxidase promoters, suggesting an important role for C/EBPepsilon in the transcriptional regulation of a subset of myeloid-specific genes. To elucidate the structure and function of C/EBPepsilon in transcriptional activation, amino acid residues 1-115, 147-249, or 1-249 of C/EBPepsilon were fused to the yeast GAL4 DNA binding domain. These expression vectors were cotransfected with a chloramphenicol acetyltransferase reporter gene and, in all cell lines tested, only the GAL-C/EBPepsilon-(1-115) fusion protein significantly activated expression from the chloramphenicol acetyltransferase reporter gene. Sixteen deletion mutants of C/EBPepsilon mapped the transactivation domain to amino acids 1-18 at the N terminus and revealed the presence of a transcription repression element between amino acid residues 116 and 162. Expression vectors containing the repression domain of C/EBPepsilon strongly inhibited gene transcription from TK, SV40, and adenoviral major late promoters bearing GAL4 binding sites. Fusion of this repression domain to the VP16 activation domain inhibited the transactivation function of VP16. Deletion of this repression domain increased gene transcription from a neutrophil elastase promoter-luciferase reporter. Taken together, these data suggest that C/EBPepsilon regulates transcription by utilizing both activation and repression functions.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas Nucleares/química , Proteínas Repressoras/genética , Ativação Transcricional/genética , Proteínas Estimuladoras de Ligação a CCAAT , Linhagem Celular , Regulação da Expressão Gênica/genética , Genes Reporter/genética , Humanos , Elastase de Leucócito/genética , Regiões Promotoras Genéticas/genética , Proteínas Recombinantes de Fusão/química , Transfecção/genética
11.
Vopr Med Khim ; 44(2): 158-66, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9634718

RESUMO

The effect of a long-lasting loading with alpha-tocopherol on the development of dimethylnitrosamine-induced kidney tumors was investigated in 55 non-bred white male rats. The carcinogen was repeatedly introduced into the stomach by means of a gastric tube. Starting 24 days after the last administration of the carcinogen the alpha-tocopherol loading began and lasted up to the end of the experiment. 21 rats were loaded with vitamin E introduced into the stomach, 5 times a week at a dose of 70 mg/kg body weight. 17 rats received sunflower seed oil--the vitamin E solvent; other 17 rats received only standard ration. The control group (20 rats) were not treated with the carcinogen. One part of these rats received alpha-tocopherol by the above schedule while another part--sunflower oil alone. It was shown that the alpha-tocopherol loading had no effect on the incidence of renal tumors. Nevertheless it enhanced to some extent the rate of their development as well as the incidence of blastomes in other organs. Based on histological examination, tumors developed in kidneys were of epithelial and mesenchymal origins with the mesenchymal tumors occurring more frequently (63-69% of the total). Vitamin E content in tumor tissue of rats, loaded or not loaded with alpha-tocopherol, was much higher than that in intact kidneys of corresponding control animals, suggesting a high tumor tropism of this vitamin. Total lipid concentration of tumor tissue was 1.5 times lower than that of intact kidneys. Histological nature of tumors had no visible effect on their vitamin E and total lipid content.


Assuntos
Carcinógenos/toxicidade , Dimetilnitrosamina/toxicidade , Neoplasias Renais/metabolismo , Vitamina E/administração & dosagem , Vitamina E/metabolismo , Animais , Neoplasias Renais/induzido quimicamente , Neoplasias Renais/patologia , Metabolismo dos Lipídeos , Masculino , Óleos de Plantas/administração & dosagem , Ratos , Óleo de Girassol
12.
Leuk Res ; 21(9): 833-9, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9393598

RESUMO

We and others have cloned a novel human gene CCAAT/enhancer-binding protein epsilon (C/EBP-epsilon) encoding a member of the C/EBP gene family. It is exclusively expressed in myeloid and T-lymphoid cells and appears to have an important role in inducing expression of several myeloid-specific genes. We used a polymerase chain reaction (PCR)-based technique to examine DNA from 93 hamster/human radiation hybrid clones in order chromosomally to map C/EBP-epsilon to 14q11.2 (between D14S264 and D14S275) which is telomeric to the T-cell receptor alpha and delta genes and centromeric to several other myeloid gene products including Cathepsin G (CTSG) and Chymase-1 (CMA1). To determine whether C/EBP-epsilon behaves as an altered tumor-suppressor gene, samples from patients with acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS) evolving to AML were studied for loss of heterozygosity (LOH) using microsatellite sequences that we identified within 0.2 kb of the amino-terminus of the human C/EBP-epsilon gene. Allelic loss of the C/EBP-epsilon gene was detected in four out of 20 (20%) evolving MDS cases and in none of the 17 AML and 17 T-cell leukemia cases. Mutational analysis of the gene was performed using PCR-SSCP on 37 AML and 40 MDS cases including those with LOH at the gene. No abnormalities were found suggesting that the altered gene in this region is not C/EBP-epsilon. Also, C/EBP-epsilon was examined by Southern blot analysis on DNA samples from 20 AML patients and 10 AML cell lines. No rearrangements or amplifications of the gene were detected. Taken together, we have mapped C/EBP-epsilon to 14q11.2, a region containing other myeloid and T-lymphoid specific genes. Furthermore, no structural alterations were detected in the C/EBP-epsilon gene.


Assuntos
Cromossomos Humanos Par 14/genética , DNA de Neoplasias/genética , Proteínas de Ligação a DNA/genética , Leucemia/genética , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Pré-Leucemia/genética , Doença Aguda , Alelos , Animais , Proteínas Estimuladoras de Ligação a CCAAT , Mapeamento Cromossômico , Cromossomos Humanos Par 14/ultraestrutura , Cricetinae , Análise Mutacional de DNA , Genes Supressores de Tumor , Humanos , Células Híbridas , Leucemia/patologia , Leucemia Mieloide/genética , Leucemia Mieloide/patologia , Leucemia-Linfoma de Células T do Adulto/genética , Leucemia-Linfoma de Células T do Adulto/patologia , Perda de Heterozigosidade , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Pré-Leucemia/patologia , Células Tumorais Cultivadas
13.
Blood ; 90(7): 2591-600, 1997 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-9326225

RESUMO

Human C/EBP epsilon is a newly cloned CCAAT/enhancer-binding transcription factor. Initial studies indicated it may be an important regulator of human myelopoiesis. To elucidate the range of expression of C/EBP epsilon, we used reverse transcription-polymerase chain reaction (RT-PCR) analysis and examined its expression in 28 hematopoietic and 14 nonhematopoietic cell lines, 16 fresh myeloid leukemia samples, and normal human hematopoietic stem cells and their mature progeny. Prominent expression of C/EBP epsilon mRNA occurred in the late myeloblastic and promyelocytic cell lines (NB4, HL60, GFD8), the myelomonoblastic cell lines (U937 and THP-1), the early myeloblast cell lines (ML1, KCL22, MDS92), and the T-cell lymphoblastic leukemia cell lines CEM and HSB-2. For the acute promyelocytic leukemia cell line NB4, C/EBP epsilon was the only C/EBP family member that was easily detected by RT-PCR. No C/EBP epsilon mRNA was found in erythroid, megakaryocyte, basophil, B lymphoid, or nonhematopoietic cell lines. Most acute myeloid leukemia samples (11 of 12) from patients expressed C/EBP epsilon. Northern blot and RT-PCR analyses showed that C/EBP epsilon mRNA decreased when the HL60 and KG-1 myeloblast cell lines were induced to differentiate toward macrophages. Similarly, Western blot analysis showed that expression of C/EBP epsilon protein was either unchanged or decreased slightly as the promyelocytic cell line NB4 differentiated down the macrophage-like pathway after treatment with a potent vitamin D3 analog (KH1060). In contrast, C/EBP epsilon protein levels increased dramatically as NB4 cells were induced to differentiate down the granulocytic pathway after exposure to 9-cis retinoic acid. Furthermore, very early, normal hematopoietic stem cells (CD34+/CD38-), purified from humans had very weak expression of C/EBP epsilon mRNA, but levels increased as these cells differentiated towards granulocytes. Likewise, purified granulocytes appeared to express higher levels of C/EBP epsilon mRNA than purified macrophages. Addition of phosphothiolated antisense, but not sense oligonucleotides to C/EBP epsilon, decreased clonal growth of HL-60 and NB4 cells by about 50% compared with control cultures. Taken together, our results indicate that expression of C/EBP epsilon is restricted to hematopoietic tissues, especially myeloid cells as they differentiate towards granulocytes and inhibition of its expression in HL-60 and NB4 myeloblasts and promyelocytes decreased their proliferative capacity. Therefore, this transcriptional factor may play an important role in the process of normal myeloid development.


Assuntos
Proteínas de Ligação a DNA/biossíntese , Regulação da Expressão Gênica/efeitos dos fármacos , Granulócitos/citologia , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/citologia , Monócitos/citologia , Proteínas Nucleares/biossíntese , Doença Aguda , Alitretinoína , Western Blotting , Proteínas Estimuladoras de Ligação a CCAAT , Calcitriol/análogos & derivados , Calcitriol/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/isolamento & purificação , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Células HL-60/efeitos dos fármacos , Células HL-60/metabolismo , Hematopoese/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Proteínas Nucleares/isolamento & purificação , Oligonucleotídeos Antissenso/farmacologia , Reação em Cadeia da Polimerase , RNA Mensageiro/biossíntese , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Tretinoína/farmacologia
14.
Blood ; 90(8): 2987-94, 1997 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-9376579

RESUMO

Human C/EBP epsilon is a newly cloned gene coding for a CCAAT/enhancer binding protein that may be involved in the regulation of myeloid differentiation. Our studies showed that levels of C/EBP epsilon mRNA were markedly increased in NB4 cells (promyelocytic leukemia line), because they were induced by 9-cis retinoic acid (9-cis RA) to differentiate towards granulocytes. Accumulation of C/EBP epsilon mRNA occurred as early as 1 hour after exposure of NB4 cells to 9-cis RA (5 x 10(-7) mol/L); and at 48 hours, levels were increased by 5.1-fold. Dose-response studies showed that 10(-7) to 10(-6) mol/L 9-cis RA (12 hours) resulted in peak levels of C/EBP epsilon mRNA; but even 10(-10) mol/L 9-cis RA increased levels of these transcripts. NB4 cells pulse-exposed (30 minutes) to all-trans retinoic acid (ATRA), washed, and cultured (3 days) with either dimethylsulfoxide (DMSO) or hexamethylene bisacetamide (HMBA) had a prominent increase in levels of C/EBP epsilon mRNA and an increase in granulocytic differentiation, but exposure to either DMSO or HMBA alone had no effect on base levels of C/EBP epsilon and did not induce differentiation. Macrophage-differentiation of NB4 reduced levels of C/EBP epsilon mRNA. Nuclear run-off assays and half-life studies showed that accumulation of C/EBP epsilon mRNA by 9-cis RA was due to enhanced transcription. Furthermore, this C/EBP epsilon mRNA accumulation did not require synthesis of new protein factors because 9-cis RA induced C/EBP epsilon mRNA accumulation in the absence of new protein synthesis. ATRA also induced expression of C/EBP epsilon protein in NB4 cells, as shown by Western blotting. In contrast to the increase of C/EBP epsilon in 9-cis RA-mediated granulocytic differentiation, the DMSO-induced differentiation of HL-60 cells down the granulocytic pathway was associated with an initial reduction of C/EBP epsilon mRNA levels. In summary, we have discovered that expression of C/EBP epsilon mRNA is markedly enhanced as the NB4 promyelocytes are induced by retinoids to differentiate towards granulocytes. This induction of C/EBP epsilon mRNA expression is transcriptionally mediated and occurs in the absence of synthesis of additional protein factors. We suspect that the C/EBP epsilon promoter/enhancer contains a retinoic acid-response element that is directly stimulated by retinoids.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas Nucleares/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/genética , Northern Blotting , Proteínas Estimuladoras de Ligação a CCAAT , Diferenciação Celular , Clonagem Molecular , Granulócitos/citologia , Células HL-60 , Humanos , Transcrição Gênica
15.
Mol Cell Biol ; 17(3): 1375-86, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9032264

RESUMO

Chicken NF-M transcription factor, in cooperation with either c-Myb or v-Myb, is active in the combinatorial activation of myeloid-cell-specific genes in heterologous cell types, such as embryonic fibroblasts. In humans, similar effects were observed with homologous members of the CCAAT/enhancer-binding protein (C/EBP) family of transcriptional regulators, especially the human homolog of chicken NF-M, C/EBP-beta (NF-IL6). However, the NF-IL6 gene is expressed in a variety of nonmyeloid cell types and is strongly inducible in response to inflammatory stimuli, making it an unlikely candidate to have an exclusive role as a combinatorial differentiation switch during myelopoiesis in human cells. By using a reverse transcription-PCR-based approach and a set of primers specific for the DNA-binding domains of highly homologous members of the C/EBP family of transcriptional regulators, we have cloned a novel human gene encoding a member of the C/EBP gene family, identified as the human homolog of CRP1, C/EBP-epsilon. A 1.2-kb cDNA encoding full-length human C/EBP-epsilon was cloned from a promyelocyte-late myeloblast-derived lambda gt11 library. Molecular analysis of the cDNA and genomic clones indicated the presence of two exons encoding a protein with an apparent molecular mass of 32 kDa and a pI of 9.5. Primer extension analysis of C/EBP-epsilon mRNA detected a single major transcription start site approximately 200 bp upstream of the start codon. The putative promoter area is similar to those of several other myeloid-cell-specific genes in that it contains no TATAAA box but has a number of purine-rich stretches with multiple sites for the factors of the Ets family of transcriptional regulators. Northern blot analyses indicated a highly restricted mRNA expression pattern, with the strongest expression occurring in promyelocyte and late-myeloblast-like cell lines. Western blot and immunoprecipitation studies using rabbit anti-C/EBP-epsilon antibodies raised against the N-terminal portion of C/EBP-epsilon (amino acids 1 to 115) showed that C/EBP-epsilon is a 32-kDa nuclear phosphoprotein. The human C/EBP-epsilon protein exhibited strong and specific binding to double-stranded DNA containing consensus C/EBP sites. Cotransfection of the C/EBP-epsilon sense and antisense expression constructs together with chloramphenicol acetyltransferase reporter vectors containing myeloid-cell-specific c-mim and human myeloperoxidase promoters suggested a role for C/EBP-epsilon transcription factor in the regulation of a subset of myeloid-cell-specific genes. Transient tranfection of a promyelocyte cell line (NB4) with a C/EBP-epsilon expression plasmid increased cell growth by sevenfold, while antisense C/EBP-epsilon caused a fivefold decrease in clonal growth of these cells.


Assuntos
Acetiltransferases , Proteínas Estimuladoras de Ligação a CCAAT , Regulação da Expressão Gênica , Genes/genética , Granulócitos , Fatores de Transcrição/genética , Sequência de Aminoácidos , Animais , Especificidade de Anticorpos , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Éxons/genética , Células HL-60 , Humanos , Camundongos , Dados de Sequência Molecular , Peso Molecular , Peroxidase/genética , Fosfoproteínas/genética , Regiões Promotoras Genéticas/genética , Proteínas/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , Proteínas Recombinantes de Fusão , Análise de Sequência de DNA , Fatores de Transcrição/química , Fatores de Transcrição/fisiologia , Transcrição Gênica/genética , Ativação Transcricional
16.
Urol Nefrol (Mosk) ; (6): 23-7, 1996.
Artigo em Russo | MEDLINE | ID: mdl-9036602

RESUMO

The level of vitamin E was measured in 31 renal carcinomas and unaffected renal cortex taken as control. Two groups were formed in respect to cell composition of the carcinoma: 14 tumors composed of clear cells; 17 tumors composed of other types cells. Vitamin E concentrations and total lipids in the tumor tissue were elevated. Despite a significant positive correlation between levels of vitamin E and lipids in cancer tissue, high content of lipids is not the main reason of vitamin E accumulation. Concentration of vitamin A measured in 17 carcinomas was similar to control as per 1 mg of tissue lipids. Blood levels of vitamin E and total lipids in 12 patients with renal cell carcinoma were significantly higher than in healthy subjects and returned to normal after nephrectomy.


Assuntos
Carcinoma de Células Renais/química , Neoplasias Renais/química , Lipídeos/análise , Vitamina A/análise , Vitamina E/análise , Adulto , Idoso , Carcinoma de Células Renais/cirurgia , Feminino , Humanos , Córtex Renal/química , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Nefrectomia , Solubilidade
17.
Mol Carcinog ; 16(2): 101-8, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8645424

RESUMO

p53 is a nuclear phosphoprotein whose function is classified as tumor suppression. Studies have shown that p53 functions by binding to p53 DNA recognition sequences and regulates transcription of growth-regulatory genes. Various p53 recognition sequences have recently been identified. pOST2 contained two copies of a palindromic high-affinity DNA-binding sequence for p53; the other p53 recognition sequences included p53-binding fragments found in the human ribosomal gene cluster (pRGC) region and in the murine muscle creatine kinase promoter (pMCK). The purpose of this study was to compare the abilities of various p53 recognition sequences to mediate transcription in the presence of endogenously produced wild-type (wt) or mutant p53. Three p53-responsive chloramphenicol acetyltransferase (CAT) reporter constructs (pOST2, pRGC, and pMCK) that contain one or two copies of p53 recognition sequences upstream of a herpes thymidine kinase (TK) promoter and CAT reporter cDNA were constructed. Either a p53-responsive gene or a control reporter gene was transfected into human carcinoma cell lines (having various p53 mutations) either with or without a wt or mutant p53 expression vector. CAT activity was assayed to measure transactivation through the various p53-responsive elements. We showed that pOST2 had a greater ability to mediate transactivation by p53 than either pRGC or pMCK. p53 with a mutation at either codon 175 or 248 was unable to transactivate a reporter gene with pOST2, pRGC, or pMCK. We found it interesting that pOST2, but not pRGC or pMCK, was able to mediate transactivation in cell lines that produce codon 273-mutant p53. These findings suggest that various sensitivities of the different p53-responsive elements to specific mutant and wt p53s may be an important factor in the role of p53 as a transcriptional activator both under normal physiological conditions and during carcinogenesis.


Assuntos
Carcinoma/genética , Ativação Transcricional , Proteína Supressora de Tumor p53/fisiologia , Sequência de Bases , Carcinoma/metabolismo , Cloranfenicol O-Acetiltransferase/genética , Cloranfenicol O-Acetiltransferase/metabolismo , Códon , Humanos , Dados de Sequência Molecular , Mutação , Neuroblastoma/enzimologia , Neuroblastoma/genética , Sequências Reguladoras de Ácido Nucleico , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas
18.
Urol Nefrol (Mosk) ; (3): 3-5, 1996.
Artigo em Russo | MEDLINE | ID: mdl-8928328

RESUMO

113 hydronephrosis children underwent Andersen-Hynes operation, 62 Calp de Werd operation. The ureteropelvic segment was examined morphologically. 3 macroscopic variants of ureteral structure and 5 variants of leiomyocyte presence in the muscular lining of the ureter are defined. Long-term follow-up results (1-10 years) are available. Resection gave positive results in 80%, graft plastic repair was effective in 92% of cases.


Assuntos
Hidronefrose/cirurgia , Rim/cirurgia , Criança , Seguimentos , Humanos , Hidronefrose/patologia , Rim/patologia , Músculo Liso/patologia , Músculo Liso/cirurgia , Nefrectomia/métodos , Ureter/patologia , Ureter/cirurgia
19.
Urol Nefrol (Mosk) ; (1): 4-5, 1995.
Artigo em Russo | MEDLINE | ID: mdl-7732631

RESUMO

Current views of foreign investigators on refluxogenic nephropathy rest on the results of pig experiments. The authors studied human material: kidneys of children who died of pyelonephritis caused by vesicoureteral reflux. Electron-microscopic and other morphological examinations of the kidney pelvic wall provided evidence for a distinct difference in relevant morphological structures observed in congenital versus acquired reflux. Congenital vesicoureteral reflux displays a specific morphological picture suggesting congenital refluxogenic nephropathy, whereas acquired reflux produces a typical picture of ascending pyelonephritis.


Assuntos
Rim/patologia , Nefrose/patologia , Pielonefrite/patologia , Refluxo Vesicoureteral/congênito , Refluxo Vesicoureteral/patologia , Adolescente , Atrofia/etiologia , Atrofia/patologia , Biópsia , Criança , Pré-Escolar , Doença Crônica , Humanos , Nefrectomia , Nefrose/etiologia , Pielonefrite/etiologia , Refluxo Vesicoureteral/complicações
20.
Nephron ; 69(4): 449-53, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7777111

RESUMO

Vitamin E was quantified in renal cell carcinomas (RCC) and in 'intact' renal cortex, obtained from 31 patients subjected either to unilateral nephrectomy or to partial resection of the only kidney. Histologically, 14 tumors consisted predominantly of clear cells (group 1) and 17 of other cell types (group 2). In both groups, a significant increase in vitamin E concentration, as compared to the 'intact' cortex, was observed: 167.8 +/- 27.9 and 68.2 +/- 15.2 micrograms/g wet tissue weight (mean +/- SEM) for groups 1 and 2, respectively, versus 10.1 +/- 0.53 micrograms/g wet tissue weight for the cortex. Although the total lipid content was also increased in tumors (especially in group 1), the vitamin E concentration in tumor tissue, calculated per milligram of total lipids, proved to be much higher in both groups than in 'intact' cortex. A significant positive correlation was observed between vitamin E and total lipid content in group 1 and 2 carcinomas. It was also found that vitamin E accumulation in RCC is unlikely to be attributed to an enhanced lipid deposit in the tumor cells. Thus, in 8 tumors of group 2 the vitamin E levels were markedly enhanced although these tumors did not differ from the cortex in total lipid concentrations. Vitamin A content determined in 17 carcinomas, when calculated per milligram of total lipids, was the same as in 'intact' cortex.


Assuntos
Carcinoma de Células Renais/metabolismo , Córtex Renal/metabolismo , Neoplasias Renais/metabolismo , Vitamina A/metabolismo , Vitamina E/metabolismo , Adulto , Idoso , Feminino , Humanos , Metabolismo dos Lipídeos , Masculino , Pessoa de Meia-Idade , Solubilidade
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