Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
Alcohol Clin Exp Res ; 39(2): 205-11, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25684044

RESUMO

BACKGROUND: Alcohol dependence (AD) is a complex psychiatric disorder, affecting 5.4% of the general population lifetime, characterized by excessive alcohol consumption influenced by environmental risk factors and genetic factors. Genetic alterations in dopaminergic system are involved in the treatment and etiology of AD. The aim of this search was to test the association of the SLC6A3 40 bp-VNTR and DRD2/ANKK1 Taq1A single nucleotide polymorphism (SNP), a transporter and receptor of the dopaminergic system, with AD through a study in a population of northeastern Brazil. METHODS: The study design was a case-control that included 227 males of northeastern Brazil (113 alcoholics and 114 controls). Alcoholics were classified according to the DSM-IV criteria for AD and controls were subjects who had nonalcohol problems or who never drank. Genotyping was detected through polymerase chain reaction (PCR) for SLC6A3 40 bp-VNTR and RFLP-PCR for DRD2/ANKK1 Taq1A, and subsequent electrophoresis on a 2% agarose gel. The distribution of allele and genotype frequencies and association of polymorphisms with AD were assessed by chi-square, Fisher's exact test, and odds ratio (OR) with a confidence interval of 95% and significance p < 0.05. Data were analyzed on BioEstat 5.3 software. RESULTS: The SLC6A3 40 bp-VNTR was associated with AD, allelic, and genotypic frequencies were significantly different, respectively (A9 vs. A10: OR = 1.88; p = 0.01; A9/A9 vs. A10/A10: OR = 6.25; p = 0.02; A9/A9 vs. A9/A10 + A10A10: OR = 5.44; p = 0.03). However, there was no statistically significant difference when the allelic (p = 0.10) and genotypic (p > 0.05) frequencies for DRD2/ANKK1 Taq1A were compared. CONCLUSIONS: These findings suggest that A9 allele and A9/A9 genotype of the SLC6A3 40 bp-VNTR are involved in the vulnerability to AD in the population studied. However, for the DRD2/ANKK1 SNP does not present contributions to the development of AD.


Assuntos
Alcoolismo/genética , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Proteínas Serina-Treonina Quinases/genética , Receptores de Dopamina D2/genética , População Branca/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Estudos de Casos e Controles , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Repetições Minissatélites , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , Adulto Jovem
2.
Mol Cell Biochem ; 364(1-2): 217-23, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22215203

RESUMO

Susceptibility to acute lymphoblastic leukemia can be highly influenced by genetic polymorphisms in metabolizing enzyme genes of environmental carcinogens. This study aimed to evaluate the impact of the CYP3A5 and NAT2 metabolizing enzyme polymorphisms on the risk of childhood acute lymphoblastic leukemia. The analysis was conducted on 204 ALL patients and in 364 controls from a Brazilian population, using PCR-RFLP. The CYP3A5 3 polymorphic homozygous genotype was more frequent among ALL patients and the 3 allele variant was significantly associated with increased risk of childhood ALL (OR = 0.29; 95% CI, 0.14-0.60). The homozygous polymorphic genotype for the 6 allele variant was extremely rare and found in only two individuals. The heterozygous frequencies were similar for the ALL group and the control group. No significant differences were observed between the groups analyzed regarding NAT2 variant polymorphisms. None of the polymorphisms analyzed was related to treatment outcome. The results suggest that CYP3A5 3 polymorphism may play an important role in the risk of childhood ALL.


Assuntos
Arilamina N-Acetiltransferase/genética , Citocromo P-450 CYP3A/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Fatores de Risco , Arilamina N-Acetiltransferase/sangue , Brasil , Citocromo P-450 CYP3A/sangue , Intervalo Livre de Doença , Etnicidade , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Polimorfismo Genético , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Resultado do Tratamento
3.
Biomarkers ; 14(2): 111-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19330589

RESUMO

Polymorphic variations of several genes associated with drugs and xenobiotic metabolism have been linked to the factors that predispose to the carcinogenesis process. As considerable interindividual and interethnic variation in metabolizing enzyme activity has been associated with polymorphic alleles, we evaluated the frequency of the polymorphisms of CYP2D6, EPHX1 and NQO1 genes in 361 Brazilian individuals separated by ethnicity (European and African ancestry), using the polymerase chain reaction-restriction fragment length (PCR-RFLP) method. The allele frequencies of the variants *3 and *4 for the gene CYP2D6 were 0.04 and 0.14 for white subjects and 0.03 and 0.10 for black individuals, respectively. For the both variants of the gene EPHX1, we found higher allele frequencies among white individuals compared with mulatto subjects (0.62 vs 0.54 and 0.18 vs 0.14, respectively); however, these differences were not statistically significant (p = 0.39 and 0.56, respectively). For the NQO1 gene we observed a higher frequency of the homozygous genotype among black individuals (7.9%) compared with white subjects (6.3%) (p = 0.003). The genotype frequencies were within the Hardy-Weinberg equilibrium. We concluded that the allele frequencies of CYP2D6, EPHX1 and NQO1 gene polymorphisms in this Brazilian population showed ethnic variability when compared with those observed in other populations.


Assuntos
Citocromo P-450 CYP2D6/genética , Epóxido Hidrolases/genética , Genética Populacional , NAD(P)H Desidrogenase (Quinona)/genética , Polimorfismo Genético , Xenobióticos/metabolismo , Adolescente , Sequência de Bases , Brasil , Criança , Pré-Escolar , Primers do DNA , Feminino , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Adulto Jovem
4.
Environ Mol Mutagen ; 47(9): 725-32, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17111423

RESUMO

Polymorphisms in genes responsible for maintaining genomic integrity are potential modifiers of disease risk. Since considerable interindividual and interethnic variation in DNA repair capacity has been associated with polymorphic alleles, we evaluated the frequency of the 2R/3R variants in the TS promoter, Arg194Trp and Arg399Gln in the XRCC1 gene, and Asp312Asn and Lys751Gln in the XPD gene in 364 healthy individuals from a Brazilian population separated by ethnicity (European ancestry and African ancestry). The genotypes were determined by PCR (TS) or by PCR-RFLP (XRCC1 and XPD). The frequency of the TS 3R allele was 0.56 for whites and 0.51 for nonwhites. In the case of the XRCC1 MspI polymorphism, the allele frequencies were 0.09 for 194Trp in both nonwhites and whites and 0.27 and 0.28 for 399Gln in nonwhites and whites, respectively. For the XPD 312Asn allele, we found a frequency of 0.25 in white individuals, which was significantly different (P = 0.025) from that seen in nonwhites (0.15). Similarly, the 751Gln polymorphic allele of the XPD gene was significantly more frequent (P < 0.002) in whites (0.30) than in nonwhites (0.20). The genotype frequencies were within Hardy-Weinberg equilibrium. We concluded that the genotype and allele frequencies of XPD gene polymorphism differed between white and nonwhite Brazilians, and that the frequencies of the XPD 312Asn and XRCC1 399Gln alleles in this Brazilian population showed ethnic variability when compared with those observed in other populations.


Assuntos
Proteínas de Ligação a DNA/genética , Timidilato Sintase/genética , Proteína Grupo D do Xeroderma Pigmentoso/genética , Brasil , Criança , Pré-Escolar , Reparo do DNA , Feminino , Frequência do Gene , Genótipo , Humanos , Lactente , Masculino , Polimorfismo Genético , Regiões Promotoras Genéticas , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
5.
Environ Mol Mutagen ; 43(2): 100-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14991750

RESUMO

Acute lymphoblastic leukemia (ALL) is the most common form of pediatric cancer. Although exposure to environmental agents appears to predispose individuals to this disease, little attention has been paid to the role of genetic susceptibility to environmental exposures in the etiology of childhood ALL. The enzymes GSTM1, GSTT1, GSTP1, CYP1A1, and CYP2E1 are involved in the bioactivation and detoxification of a variety of xenobiotics present in food, organic solvents, tobacco smoke, drugs, alcoholic drinks, pesticides, and environmental pollutants. Polymorphisms in the genes coding for these enzymes have been associated with increased susceptibility to different cancers, including hematologic malignancies. To investigate whether these polymorphisms represent risk-modifying factors for childhood ALL, a study was conducted involving 113 Brazilian patients of childhood ALL and 221 controls with similar ethnic backgrounds. The data revealed that carriers of the rare GSTP1 Val allele were at higher risk of ALL (odds ratio [OR] = 2.7; 95% confidence interval [CI] = 1.1-6.8; P = 0.04). No difference was found in the prevalence of the GSTM1 and GSTT1 null genotypes between ALL patients and the controls, and no association was found between CYP1A1*2 and CYP2E1*3 variants and ALL. However, when the mutant CYP1A1 and CYP2E1 alleles were considered together with the GSTM1 and GSTP1 risk-elevating genotypes, the risk of ALL was increased further (OR = 10.3; 95% CI = 1.0-111.8; P = 0.05), suggesting a combined effect. These results imply that genetic variants of xenobiotic metabolizing genes influence the risk of developing childhood ALL.


Assuntos
Hidrocarboneto de Aril Hidroxilases/genética , Glutationa Transferase/genética , Polimorfismo Genético , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adolescente , Brasil , Criança , Pré-Escolar , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP2E1/genética , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença , Glutationa S-Transferase pi , Humanos , Lactente , Isoenzimas/genética , Linfócitos/enzimologia , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/enzimologia
6.
Mutat Res ; 560(2): 187-98, 2004 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-15157656

RESUMO

Alcoholism is one of the main causes of damage for human health, being relevant to study the induction of chromosomal aberrations (CA) by ethanol, and to investigate the individual susceptibility to diseases caused by alcoholism. A cytogenetic study was performed in human peripheral blood lymphocytes of 29 heavy chronic alcoholics, 11 alcoholics in abstinence, and 10 controls. The values of the chromosomal aberrations, mitotic indexes (MI) and proliferation indexes (PI) were determined. A molecular cytogenetic study was also carried out using fluorescence in situ hybridization (FISH) method with DNA library probes for chromosomes 1, 3 and 6, in lymphocytes from chronic alcoholic individuals in comparison with a control group. The results showed that the CA frequencies for chronic alcoholics (5.15 CA/100 cells) and alcoholics in abstinence (3.87 CA/100 cells) were higher than those obtained for control individuals (1.72 CA/100 cells). The mean translocation frequencies (equivalent to the genome) were calculated for six chronic alcoholics (0.267 translocations/100 cells) and six alcoholics in abstinence (0.167 translocations/100 cells), whose values were significantly higher than those observed for six control individuals (0.067 translocations/100 cells). The CA frequencies were not statistically different when smoker and non-smoker alcoholics were compared, indicating that although the smoking habit had significantly increased (four-fold) the CA frequency in healthy control individuals, a lack of interaction effect was observed within the group of alcoholics when smokers and non-smokers were compared. The CA frequencies presented by alcoholics in abstinence were similar to those obtained for chronic alcoholics. Therefore, chronic ethanol intoxication can lead to chromosome damage and disturbances in the metabolism of endogenous and exogenous compounds, which may persist for a long time, and constitute a relevant factor of risk for the development of neoplasias.


Assuntos
Alcoolismo/genética , Etanol/toxicidade , Mutagênicos/toxicidade , Estudos de Casos e Controles , Aberrações Cromossômicas , Doença Crônica , Humanos , Hibridização in Situ Fluorescente , Translocação Genética
7.
J Med Case Rep ; 7: 78, 2013 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-23506330

RESUMO

INTRODUCTION: Brugada syndrome is a hereditary arrhythmia characterized by a specific electrocardiographic pattern and an increased risk of sudden cardiac death, with an apparent absence of structural abnormalities or ischemic heart disease. To date, mutations in the sodium channel, voltage-gated, type V, alpha subunit gene and glycerol-3-phosphate dehydrogenase 1-like gene are estimated to account for approximately 28% of Brugada syndrome probands. CASE PRESENTATION: We report the case of a 32-year-old mixed-race Brazilian man who is sodium channel, voltage-gated, type V, alpha subunit gene and glycerol-3-phosphate dehydrogenase 1-like gene mutation-negative with a type 1 Brugada electrocardiographic pattern and a history of high family mortality, including five sudden deaths among relatives of whom four were first-degree relatives. CONCLUSION: To the best of our knowledge, this is the first case of a patient who has Brugada syndrome and a history of sudden death in four first-degree family members. This case report reinforces the evidence that genetic studies are of limited use while determining risk but remain helpful for diagnosis, and that diagnosis via electrocardiography is of great importance in preventing adverse events and stratifying risk. Although there are several technologically advanced diagnostic tools, they might not be accessible in small towns and hospitals; however, a basic diagnostic tool like electrocardiography is easily accessible.

8.
Leuk Lymphoma ; 52(6): 1118-26, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21463130

RESUMO

The aim of this study was to evaluate the frequency of polymorphisms in the TYMS, XRCC1, and ERCC2 DNA repair genes in pediatric patients with acute lymphoblastic leukemia using polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (RFLP) approaches. The study was conducted in 206 patients and 364 controls from a Brazilian population. No significant differences were observed among the analyzed groups regarding XRCC1 codon 399 and codon 194 and ERCC2 codon 751 and codon 312 polymorphisms. The TYMS 3R variant allele was significantly associated with a reduced risk of childhood ALL, represented by the sum of heterozygous and polymorphic homozygous genotypes (odds ratio 0.60; 95% confidence interval 0.37-0.99). The results suggest that polymorphism in TYMS may play a protective role against the development of childhood ALL.


Assuntos
Proteínas de Ligação a DNA/genética , Polimorfismo Genético , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Regiões Promotoras Genéticas/genética , Timidilato Sintase/genética , Proteína Grupo D do Xeroderma Pigmentoso/genética , Adolescente , Brasil , Criança , Pré-Escolar , Reparo do DNA/genética , Feminino , Frequência do Gene , Genótipo , Humanos , Lactente , Masculino , Razão de Chances , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
9.
Environ Mol Mutagen ; 51(1): 48-56, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19593802

RESUMO

Polymorphic variations of several genes associated with dietary effects and exposure to environmental carcinogens may influence susceptibility to leukemia development. The objective of the present study was to evaluate the effect of the polymorphisms of debrisoquine hydroxylase (CYP2D6), epoxide hydrolase (EPHX1), myeloperoxidase (MPO), and quinone-oxoreductase (NQO1), which have been implicated in xenobiotic metabolism, on the risk of childhood acute lymphoblastic leukemia (ALL). We evaluated the frequency of polymorphisms in the CYP2D6 (*3 and *4), EPHX1 (*2 and *3), MPO (*2), and NQO1 (*2) genes in 206 patients with childhood ALL and in 364 healthy individuals matched for age and gender from a Brazilian population separated by ethnicity (European ancestry and African ancestry), using the PCR-RFLP method. The CYP2D6 polymorphism variants were associated with an increased risk of ALL. The EPHX1, NQO1, and MPO variant genotypes were significantly associated with a reduced risk of childhood ALL. A significantly stronger protective effect is observed when the EPHX1, NQO1, and MPO variant genotypes are combined suggesting that, CYP2D6 polymorphisms may play a role in the susceptibility to pediatric ALL, whereas the EPHX1, NQO1, and MPO polymorphisms might have a protective function against leukemogenesis.


Assuntos
Citocromo P-450 CYP2D6/genética , Epóxido Hidrolases/genética , Predisposição Genética para Doença , Fator Estimulador de Colônias de Granulócitos/genética , Interleucina-3/genética , NAD(P)H Desidrogenase (Quinona)/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas Recombinantes de Fusão/genética , Adolescente , Brasil , Feminino , Humanos , Lactente , Masculino , Proteínas Recombinantes
10.
Clin Chim Acta ; 411(17-18): 1335-40, 2010 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-20510681

RESUMO

BACKGROUND: Angiogenesis has been shown as an important process in hematological malignancies. It consists in endothelial proliferation, migration, and tube formation following pro-angiogenic factors releasing, specially the vascular endothelial growth factor (VEGF), which angiogenic effect seems to be dependent on nitric oxide (NO). We examined the association among functional polymorphisms in these two angiogenesis related genes: VEGF (-2578C>A, -1154G>A, and -634G>C) and NOS3 (-786T>C, intron 4 b>a, and Glu298Asp) with prognosis of childhood acute lymphoblastic leukemia (ALL). METHODS: The genotypes were determined and haplotypes estimated in 105 ALL patients that were divided in 2 groups: high risk (HR) and low risk of relapse (LR) patients. In addition, event-free survival curves according to genotypes were assessed. RESULTS: The group HR compared to the LR showed a higher frequency of the alleles -2578C and -634C and the haplotype CGC for VEGF (0.72 vs. 0.51, p<0.008; 0.47 vs. 0.26, p<0.008; and 42.1 vs. 14.5, p<0.006; respectively) and a lower frequency of the haplotype CbGlu (0.4 vs. 8.8,p<0.006), for NOS3. CONCLUSION: Polymorphisms of VEGF and NOS3 genes are associated with high risk of relapse, therefore may have a prognostic impact in childhood ALL.


Assuntos
Óxido Nítrico Sintase Tipo III/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Fator A de Crescimento do Endotélio Vascular/genética , Sequência de Bases , Criança , Pré-Escolar , Primers do DNA , Intervalo Livre de Doença , Feminino , Genótipo , Haplótipos , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/enzimologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Recidiva , Fatores de Risco
11.
Sao Paulo Med J ; 127(5): 288-94, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20169278

RESUMO

CONTEXT AND OBJECTIVE: Genetic investigation of central nervous system (CNS) tumors provides valuable information about the genes regulating proliferation, differentiation, angiogenesis, migration and apoptosis in the CNS. The aim of our study was to determine the prevalence of genetic polymorphisms (codon 31 and 3' untranslated region, 3'UTR) and protein expression of the cyclin-dependent kinase inhibitor 1A (CDKN1A) gene in patients with and without CNS tumors. DESIGN AND SETTING: Analytical cross-sectional study with a control group, at the Molecular Biology Laboratory, Pediatric Oncology Department, Hospital das Clínicas de Ribeirão Preto. METHODS: 41 patients with CNS tumors and a control group of 161 subjects without cancer and paires for sex, age and ethnicity were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Protein analysis was performed on 36 patients with CNS tumors, using the Western Blotting technique. RESULTS: The frequencies of the heterozygote (Ser/Arg) and polymorphic homozygote (Arg/Arg) genotypes of codon 31 in the control subjects were 28.0% and 1.2%, respectively. However, the 3'UTR site presented frequencies of 24.2% (C/T) and 0.6% (T/T). These frequencies were not statistically different (P > 0.05) from those seen in the patients with CNS tumors (19.4% and 0.0%, codon 31; 15.8% and 2.6%, 3'UTR site). Regarding the protein expression in ependymomas, 66.67% did not express the protein CDKN1A. The results for medulloblastomas and astrocytomas were similar: neither of them expressed the protein (57.14% and 61.54%, respectively). CONCLUSION: No significant differences in protein expression patterns or polymorphisms of CDKN1A in relation to the three types of CNS tumors were observed among Brazilian subjects.


Assuntos
Neoplasias Encefálicas/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Proteínas de Neoplasias/genética , Polimorfismo Genético/genética , Regiões 3' não Traduzidas/genética , Adolescente , Neoplasias Encefálicas/metabolismo , Criança , Pré-Escolar , Códon/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Métodos Epidemiológicos , Feminino , Humanos , Lactente , Masculino , Proteínas de Neoplasias/metabolismo , Adulto Jovem
12.
Leuk Res ; 33(7): 898-901, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19162321

RESUMO

The interindividual variation in the activity of xenobiotic metabolizing enzymes and DNA repair genes could modify an individual's risk of recurrent malignancy and response to therapy. We investigated whether ALL outcome was related to polymorphisms in genes CYP2D6, MPO, EPHX1, NQO1, TS, XPD and XRCC1 in 95 consecutive ALL children by PCR or PCR-FRLP techniques. Polymorphisms in genes NQO1 and TS were associated with a significantly slow response to induction chemotherapy and NQO1 was also associated with a lower five-year event-free survival. This study suggests that polymorphisms of NQO1 and TS could be important for patient response to induction therapy and for treatment outcome.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Enzimas Reparadoras do DNA/genética , Polimorfismo Genético/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Criança , Citocromo P-450 CYP2D6/genética , Reparo do DNA , Proteínas de Ligação a DNA/genética , Epóxido Hidrolases/genética , Feminino , Citometria de Fluxo , Fator Estimulador de Colônias de Granulócitos/genética , Humanos , Interleucina-3/genética , Masculino , NAD(P)H Desidrogenase (Quinona)/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prognóstico , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes , Indução de Remissão , Taxa de Sobrevida , Timidilato Sintase/genética , Resultado do Tratamento , Proteína 1 Complementadora Cruzada de Reparo de Raio-X , Proteína Grupo D do Xeroderma Pigmentoso/genética
13.
Mutagenesis ; 19(4): 291-8, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15215328

RESUMO

Excessive alcohol consumption may cause the development of pathologies in the liver and pancreas and various digestive tract cancers. The enzymes GSTM1, GSTT1, GSTP1, CYP1A1 and CYP2E1 are involved in the bioactivation and detoxification of a variety of xenobiotics present in food, organic solvents, tobacco smoke, drugs, pesticides, environmental pollutants and alcoholic drinks. Polymorphisms in the genes coding for these enzymes have been associated with susceptibility to different diseases, including ethanol-related diseases. To investigate whether these polymorphisms represent risk-modifying factors for ethanol-related diseases, a study was conducted involving 120 Brazilian alcoholics and 221 controls with similar ethnic backgrounds. The distribution of alcoholics groups was as follows: 65 with liver cirrhosis, 14 with chronic pancreatitis and 41 without cirrhosis or pancreatitis. The data revealed that carriers of the rare GSTP1 Val allele were at higher risk of liver cirrhosis and pancreatitis, since we found higher frequencies of the Val/Val genotype in alcoholics with liver cirrhosis (15.4%) and pancreatitis (28.6%) in comparison with alcoholics without disease (7.3%). No differences were found in the prevalences of the GSTM1 and GSTT1 null genotypes between alcoholics and the controls and no association was found between the rare CYP2E1 c2 allele and liver cirrhosis and pancreatitis. However, when the mutant CYP1A1 allele was compared between alcoholics and controls, the m2/m2 genotype was more prevalent in the liver cirrhosis alcoholics (7.7%) than in the controls (1.4%) and this difference was statistically significant (P = 0.03, OR = 5.33). In conclusion, our data indicate an association between occurrence of the Val/Val GSTP1 genotype and chronic pancreatitis and an association between the m2/m2 CYP1A1 genotype and alcoholic liver cirrhosis. This could indicate that persons with these genotypes are genetically more prone to the development of alcoholic pancreatitis and alcoholic cirrhosis, respectively.


Assuntos
Alcoolismo/enzimologia , Alcoolismo/genética , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP2E1/genética , Glutationa Transferase/genética , Polimorfismo Genético , Aciltransferases/genética , Adulto , Idoso , Alcoolismo/complicações , Sequência de Bases , Estudos de Casos e Controles , Doença Crônica , Primers do DNA/genética , Feminino , Frequência do Gene , Humanos , Cirrose Hepática Alcoólica/enzimologia , Cirrose Hepática Alcoólica/etiologia , Cirrose Hepática Alcoólica/genética , Masculino , Pessoa de Meia-Idade , Pancreatite Alcoólica/enzimologia , Pancreatite Alcoólica/etiologia , Pancreatite Alcoólica/genética
14.
São Paulo med. j ; 127(5): 288-294, Sept. 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-538382

RESUMO

Context and objective: Genetic investigation of central nervous system (CNS) tumors provides valuable information about the genes regulating proliferation, differentiation, angiogenesis, migration and apoptosis in the CNS. The aim of our study was to determine the prevalence of genetic polymorphisms (codon 31 and 3' untranslated region, 3'UTR) and protein expression of the cyclin-dependent kinase inhibitor 1A (CDKN1A) gene in patients with and without CNS tumors. Design and setting: Analytical cross-sectional study with a control group, at the Molecular Biology Laboratory, Pediatric Oncology Department, Hospital das Clínicas de Ribeirão Preto. Methods: 41 patients with CNS tumors and a control group of 161 subjects without cancer and paires for sex, age and ethnicity were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Protein analysis was performed on 36 patients with CNS tumors, using the Western Blotting technique. Results: The frequencies of the heterozygote (Ser/Arg) and polymorphic homozygote (Arg/Arg) genotypes of codon 31 in the control subjects were 28.0 percent and 1.2 percent, respectively. However, the 3'UTR site presented frequencies of 24.2 percent (C/T) and 0.6 percent (T/T). These frequencies were not statistically different (P > 0.05) from those seen in the patients with CNS tumors (19.4 percent and 0.0 percent, codon 31; 15.8 percent and 2.6 percent, 3'UTR site). Regarding the protein expression in ependymomas, 66.67 percent did not express the protein CDKN1A. The results for medulloblastomas and astrocytomas were similar: neither of them expressed the protein (57.14 percent and 61.54 percent, respectively). Conclusion: No significant differences in protein expression patterns or polymorphisms of CDKN1A in relation to the three types of CNS tumors were observed among Brazilian subjects.


Contexto e objetivo: A investigação genética dos tumores do sistema nervoso central (SNC) provê valiosa informação sobre os genes que regulam a proliferação, diferenciação, angiogênese, migração e apoptose. O objetivo deste estudo é determinar a prevalência entre os polimorfismos genéticos (códon 31 e da região 3' não traduzida, 3'UTR) e a expressão protéica do gene inibidor de quinase dependente de ciclina 1A (CDKN1A) em pacientes com e sem tumor do SNC. Tipo de estudo e local: Estudo transversal analítico com grupo controle, desenvolvido no Laboratório de Biologia Molecular do Departamento de Oncologia Pediátrica do Hospital das Clínicas de Ribeirão Preto. Métodos: 41 pacientes com tumor do SNC e um grupo controle de 161 indivíduos sem câncer pareados por idade, sexo e etnia foram genotipados mediante uma reação de polimorfismo no comprimento de fragmentos de restrição (RFLP). A análise das proteínas foi realizada em 36 pacientes com tumor de SNC mediante Western Blotting. Resultados: A frequência do genótipo heterozigoto (Ser/Arg) e do homozigoto polimórfico (Arg/Arg) do códon 31 nos controles foi 28,0 por cento e 1,2 por cento, respectivamente. Entretanto, o sítio 3'UTR apresentou uma frequência de 24,2 por cento (C/T) e 0,6 por cento (T/T). Estas frequências não são significativamente diferentes (P > 0,05) daquelas observadas no grupo dos pacientes com tumor de SNC (19,4 por cento e 0,0 por cento, códon 31; 15,8 por cento e 2,6 por cento, sítio 3'UTR). Com respeito à expressão protéica, nos ependimomas, 66,67 por cento não expressaram a proteína CDKN1A. Estes resultados foram similares entre os meduloblastomas e os astrocitomas, os quais não expressaram a proteína com 57,14 por cento e 61,54 por cento, respectivamente. Conclusão: Não foram encontradas diferenças significativas entre o padrão de expressão protéica, polimorfismos de CDKN1A e os três tipos de tumores de SNC em indivíduos brasileiros.


Assuntos
Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Adulto Jovem , Neoplasias Encefálicas/genética , /genética , Proteínas de Neoplasias/genética , Polimorfismo Genético/genética , /genética , Neoplasias Encefálicas/metabolismo , Códon/genética , /metabolismo , Métodos Epidemiológicos , Proteínas de Neoplasias/metabolismo , Adulto Jovem
15.
Genet. mol. biol ; 22(3): 401-6, Sept. 1999. ilus, tab
Artigo em Inglês | LILACS | ID: lil-272851

RESUMO

O glaucolido B é uma lactona sesquiterpênica, g-lactona a,b-insaturada, isolada da Vernonia eremophila Mart. (Vernonieae, Asteraceae); apresenta atividade esquistossomicida e antimicrobiana, além de atividade analgésica. A aceitaçäo de uma substância para uso medicinal também depende de dados sobre sua toxicidade, além de sua eficiência medicinal. Assim, o objetivo deste trabalho foi testar a atividade clastogênica e citotóxica do composto glaucolido B in vitro e in vivo, utilizando linfócitos em cultura temporária e células da medula óssea de camundongos BALB/c, respectivamente. Analisaram-se o índice mitótico (MI) e as aberraçöes cromossômicas nos sistemas in vitro e in vivo, e trocas entre cromátides irmäs (SCE) e índice proliferativo (PI) somente no ensaio in vitro. Nas culturas de linfócitos humanos as concentraçöes superiores a 15 µg/ml de meio de cultura inibiram totalmente o crescimento celular. Os testes realizados com as concentraçöes 2,4 e 8 µg/ml de meio de cultura demonstraram que o glaucolido B induziu aumento significativo na freqüência de aberraçöes cromossômicas nas culturas tratadas com as duas maiores concentraçöes, e mostrou citotóxico em concentraçöes iguais ou superiores a 8 µg/ml de meio de cultura, mas näo aumentou a freqüência basal de SCE. A análise das células de medula óssea de camundongos näo revelou aumento significativo na freqüência de aberraçöes cromossômicas com a administraçäo de diferentes concentraçöes de glaucolido B (160, 320 e 640 mg/kg de peso corpóreo), e também näo interferiu na divisäo celular. Assim, este composto näo apresentou açäo clastogênica sobre células de mamíferos in vivo, no entanto teve efeito citotóxico e clastogênico in vitro, sendo necessário cautela no seu possível uso como medicamento.


Assuntos
Animais , Aberrações Cromossômicas , Lactonas , Testes de Mutagenicidade , Mamíferos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA