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1.
J Urol ; 187(2): 700-6, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22177211

RESUMO

PURPOSE: CYP1B1 activates procarcinogens in some human tissues, including the urinary tract. Changes related to genetic polymorphisms are a known risk factor for cancer. We analyzed the association between CYP1B1 sequence variations and bladder cancer. MATERIALS AND METHODS: Sequence variations in the coding region (exons 2 and 3) and the neighboring introns of CYP1B1 were analyzed by direct polymerase chain reaction and DNA sequencing in 208 unrelated patients with bladder cancer and 208 healthy controls. RESULTS: We identified 6 known single nucleotide polymorphisms organized into 2 linkage disequilibrium blocks. The Ala/Ala and Leu/Val genotypes of the Ala119Ser and Leu432Val polymorphisms were significantly more common in patients than in controls (55.3% vs 42.8% and 54.8% vs 42.3%, respectively). The strongest individual single nucleotide polymorphism risk was found under an over dominant model for Leu432Val (OR 1.65, CI 95% 1.12-2.44). The 2 susceptibility single nucleotide polymorphisms were predicted to be structured into 4 haplotypes and more than 10 diplotypes. No individual haplotype was associated with bladder cancer but the diplotype Ala-Leu/Ala-Val was significantly overrepresented in cases compared to controls (31.73% vs 17.31%, OR 2.22, 95% CI 1.36-3.62, p = 0.001). The OR was approximately 1.6 for the individual genotypes Ala/Ala and Leu/Val, which increased to 2.2 for the Ala-Leu/Ala-Val diplotype. A risk occupation had a modifying effect, increasing the crude OR of the combined genotype Ala/Ala + Leu/Val from 2.2 to 8.3. CONCLUSIONS: This study provides strong evidence for the role of common CYP1B1 variants as risk factors for bladder cancer, which increases with occupational exposure.


Assuntos
Hidrocarboneto de Aril Hidroxilases/genética , Predisposição Genética para Doença , Polimorfismo Genético , Neoplasias da Bexiga Urinária/genética , Idoso , Estudos Transversais , Citocromo P-450 CYP1B1 , Feminino , Humanos , Masculino
2.
Urol Oncol ; 30(6): 864-70, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21458313

RESUMO

PURPOSE: To estimate the prevalence and importance of GSTT1, GSTM1, and CYP1B1 genotypes in renal cell carcinoma (RCC), and to identify their value as a prognostic factor. MATERIALS AND METHODS: Cross-sectional study of a group of patients diagnosed with RCC (n = 133) and a control group (n = 208) with benign conditions and no history of tumor. Controls were selected by cumulative samples and mixed pairing. All subjects pertained to the catchment area for our hospital. Sociodemographic variables, anatomical pathology features, and presence of GSTT1, GSTM1, and CYP1B1 polymorphisms by multiplex PCR and sequencing techniques. RESULTS: There were no differences in the genotype distribution of the GSTT1 and GSTM1 genes between cases and controls. In the case of CYP1B1, the GG genotype (Ala119) was more prevalent in patients with RCC (OR = 2.08; 95% CI: 1.32-2.28) and may be implicated in 34.3% (95% CI: 16.3-52.2) of RCCs. In patients with GSTT1 deletion, TNM stages III to IV were more common (39.1%); whereas in Val432 homozygous patients in CYP1B1, Fuhrman grades 3 to 4 (54.6%) were more common. Because this was a cross-sectional study, longitudinal studies are needed in the future to confirm these data. CONCLUSIONS: No relationship between GSTT1 and GSTM1 genotypes and RCC risk was observed. Homozygous subjects with Ala119 in CYP1B1 had twice the risk of RCC as homozygous for Ser119 or heterozygotes. Patients with GSTT1 deletion had tumors of more advanced stages, and those with Val432 polymorphism in CYP1B1 had tumors of higher Fuhrman grade.


Assuntos
Hidrocarboneto de Aril Hidroxilases/genética , Carcinoma de Células Renais/genética , Predisposição Genética para Doença/genética , Glutationa Transferase/genética , Neoplasias Renais/genética , Polimorfismo de Nucleotídeo Único , Carcinoma de Células Renais/patologia , Estudos Transversais , Citocromo P-450 CYP1B1 , Genótipo , Humanos , Neoplasias Renais/patologia , Reação em Cadeia da Polimerase Multiplex , Gradação de Tumores , Estadiamento de Neoplasias
3.
BJU Int ; 107(11): 1825-32, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20942828

RESUMO

UNLABELLED: What's known on the subject? and What does the study add? Bladder cancer susceptibility may be determined by genetic differences in the activity of glutathione S-transferases, enzymes that regulate the conversion of exogenous carcinogens to excretable hydrophilic metabolites by glutathione conjugation. The discrepancy of results regarding the association of common genetic polymorphisms and complex diseases such as cancer has raised scepticism in this area of research. Although the evidence generally supports the implication of GSTM1 and GSTT1 polymorphisms in bladder cancer, there is still some debate, with some studies in favour and some against. This study shows a greater risk of bladder cancer in individuals with GSTM1 null genotype, particularly women. This relationship is less evident with GSTT1 null genotypes. Null genotypes in both genes appear to be synergistic, particularly among smokers, and to increase the predisposition to more aggressive tumours. Nevertheless, the role of GSTM1 and GSTT1 polymorphisms in predisposition to bladder cancer should be viewed with caution, due to the multifactorial genetic origin of this condition and the need for long-term longitudinal studies to confirm these results. OBJECTIVE: To estimate the prevalence and importance of GSTT1 and GSTM1 genotypes (implicated in glutathione S-transferase activity) in bladder cancer, to determine whether smoking and occupational factors influence this relationship, and to identify the value of GSTT1 and GSTM1 genotypes as prognostic factors. PATIENTS AND METHODS: A cross-sectional study was conducted with a group of patients with bladder carcinoma and a control group with benign conditions and no history of tumours. The controls were selected and paired as subjects were recruited. Sociodemographic variables, smoking, professional occupation, histological features and the presence of GSTT1 and GSTM1 polymorphisms by multiplex PCR techniques were assessed. RESULTS: GSTM1 genotypes were investigated in 201 patients and 193 controls and GSTT1 genotypes in 190 patients and 163 controls. In the patients group, GSTT1 null genotype was observed in 22.1% (not significant) and GSTM1 null genotype in 54.2% (P=0.008) (odds ratio, OR, 1.7); when considered together, 15.5% (P<0.05; OR, 3.5) of patients had both null genotypes. In the multivariate analysis, the presence of GSTM1 null genotype remained in the model (OR, 2.1) in addition to smoking and age. Subjects with bladder tumour and GSTM1 null genotype were younger than patients without gene deletion (P=0.049). Women with GSTM1 null genotype presented a higher OR than men (P=0.024). When stratified by smoking habit, smokers with both null genotypes showed an OR of 4.7. The percentage of patients with G3 tumours was higher in patients with GSTT1 null genotype (P=0.013) and in patients with both null genotypes (P=0.002). A higher percentage of infiltrating tumours was also observed in patients with both null genotypes (P=0.035). CONCLUSIONS: The data obtained in the present study suggest a higher risk of bladder cancer in individuals with the GSTM1 null genotype. This risk is twofold higher when GSTM1 and GSTT1 null genotypes are both present and is also higher in smokers. A greater predisposition for more aggressive tumours appears to exist, particularly when both null genotypes are combined. Longer-term longitudinal studies are needed to confirm these results.


Assuntos
Predisposição Genética para Doença/epidemiologia , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/genética , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Intervalos de Confiança , Estudos Transversais , Feminino , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Genótipo , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polimorfismo Genético , Prognóstico , Valores de Referência , Distribuição por Sexo , Neoplasias da Bexiga Urinária/patologia
4.
Arch. esp. urol. (Ed. impr.) ; 63(3): 235-238, abr. 2010. ilus
Artigo em Espanhol | IBECS | ID: ibc-85830

RESUMO

OBJETIVOS: Recordar la presencia de tumores testiculares secundarios y revisar la literatura acerca de esta patología.MÉTODOS: Presentamos un paciente con tumor mucosecretor testicular metastásico atendido en urgencias por un cuadro de escroto agudo diez meses después de ser intervenido de un tumor combinado de ciego. La aparición de este tipo de tumores es rara, y el tratamiento de elección es la orquiectomía pero aún así el pronóstico de este tipo de metástasis es malo.RESULTADOS: Los tumores mucinosos pueden presentar diseminación de modo tardío; por lo que es necesario un seguimiento a largo plazo evaluando los lugares más frecuente de asiento. El paciente falleció a los 21 meses del diagnóstico.CONCLUSIONES: La metástasis testiculares y de tumor intestinal mucosecretor son raras. Generalmente afectan a mayores de 60 años, pero también aparecen en jóvenes. Como en los tumores primarios el tratamiento es la orquiectomía(AU)


OBJECTIVES: We review the literature about secondary testicular tumors.METHODS: We present the case of a patient with a metastatic mucus-secreting testicular tumor who presented in the emergency room with symptoms of acute scrotum 10 months after surgery for a mixed tumor of the cecum. This type of tumor is rare, and the treatment of choice is orchiectomy; nevertheless, the prognosis of such metastasis remains poor.RESULTS: Because mucinous tumors can present late dissemination, long-term follow-up with assessment of the most common sites of metastasis is necessary. Our patient died 21 months after the initial diagnosisCONCLUSIONS: Testicular metastases and mucus-secreting intestinal tumor metastases are rare. These tumors occur in patients older than 60 years of age and young men. As in the case of primary tumors, the treatment is orchiectomy(AU)


Assuntos
Humanos , Masculino , Adulto , Neoplasias do Ceco/complicações , Metástase Neoplásica/diagnóstico , Metástase Neoplásica/terapia , Neoplasias Testiculares/cirurgia , Testículo/patologia , Testículo , Ultrassonografia Doppler , Orquiectomia/métodos , Orquiectomia , Colectomia
5.
Arch Esp Urol ; 61(1): 27-33, 2008.
Artigo em Espanhol | MEDLINE | ID: mdl-18405025

RESUMO

OBJECTIVES: To review the current diagnosis and treatment of Leydig cell testicular tumors, with special attention to conservative treatment. METHODS: We report two cases of Leydig cell tumor in young adults, diagnosed two years after the appearance of bilateral gynecomastia as first clinical symptom. RESULTS: One year and eight months after orchyectomy, respectively, clinical symptoms completely disappear in the first case and significantly improved in the second. CONCLUSIONS: Around 10% of the cases, and only in adult patients, these tumors may be malignant, being radical orchyectomy the treatment of choice, although conservative surgery may be performed. Independently of the operation, follow-up must be prolonged.


Assuntos
Tumor de Células de Leydig/diagnóstico , Tumor de Células de Leydig/cirurgia , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/cirurgia , Adulto , Humanos , Masculino
6.
BJU Int ; 102(4): 504-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18325052

RESUMO

OBJECTIVES: To analyse the implications of DNA mismatch repair genes hMLH1 and hMSH2 in sporadic renal cell carcinoma (RCC). MATERIALS AND METHODS: Specimens of tumour and healthy renal tissue were collected from 89 patients treated for sporadic RCC. Another 95 blood samples taken from individuals with no history of cancer were also analysed. After DNA extraction and PCR amplification, microsatellite instability (MSI) was determined using the Bethesda microsatellite panel, two exonic microsatellites of the TGFbRII and BAX genes, and the microsatellite D3S1611. The promoter methylation status of hMLH1 was investigated using the HpaII and MspI restriction enzymes. In addition, a sequencing analysis of complete coding region of hMLH1 and hMSH2 genes was performed. RESULTS: MSI and promoter hypermethylation of hMLH1 were not detected. Interestingly, loss of heterozygosity (LOH) was common among patients with RCC, particularly in microsatellite D3S1611 (34.9%). Mutations were identified in eight patients: K618A and V716M in gene hMLH1; and I145V, G322D, and the novel mutation P349A, in gene hMSH2. The mutations also appeared in healthy renal tissue and therefore, were considered as germline DNA sequence variations. There were G322D and K618A changes in >1% of the healthy control subjects, suggesting that they are DNA polymorphisms. CONCLUSIONS: Our data show that loss of function of both hMLH1 and hMSH2 is not involved in sporadic RCC, either by promoter methylation or mutation in their exons. However, LOH indicated that chromosomal instability affecting large fragments of DNA was the main genetic alteration we detected associated with RCC.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Carcinoma de Células Renais/genética , Reparo de Erro de Pareamento de DNA , Neoplasias Renais/genética , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Idoso , Carcinoma de Células Renais/cirurgia , Estudos de Casos e Controles , Estudos Transversais , Metilação de DNA , Feminino , Humanos , Neoplasias Renais/cirurgia , Perda de Heterozigosidade/genética , Masculino , Instabilidade de Microssatélites , Proteína 1 Homóloga a MutL , Proteínas MutL , Mutação/genética , Reação em Cadeia da Polimerase
7.
Urol Oncol ; 26(6): 620-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18367096

RESUMO

OBJECTIVE: To determine the prognostic value of p53 gene mutations and P53 overexpression for predicting the incidence of recurrence, progression and long-term survival of patients with transitional cell carcinoma (TCC) of the bladder. METHODS: Prospective cohort study with 94 consecutive patients diagnosed and treated for TCC. DNA was obtained from tumor tissue to perform PCR-SSCP of p53 exons 5-9, with automatic sequencing of any mutated samples. Immunohistochemistry using anti-human P53 monoclonal antibody was also performed. Survival was analyzed and the survival curves compared (Mantel-Haenszel). Lastly, a Cox proportional hazards model was constructed. RESULTS: Mutations were found in 46.8% of samples, with 61.8% in infiltrating tumors. Exon 8 was involved in 42.3%. P53 overexpression (cutoff > or =20%) was found in 52.1%. Mean follow-up was 44.1 months; 43.6% had died by the end of this period. Mean survival was lower in patients with exon 8 mutations (38.4 months), compared with patients without this exon mutated (P = 0.016). There were no differences in patient survival based on positive or negative immunohistochemistry (cutoff > or =20%), although survival was lower in patients with a percentage higher than 50% of antibody-stained cells (P = 0.02). In the Cox analysis, tumor stage, pM stage, and interaction between stage > or =pT2 and mutated p53 gene were independent risk factors, with a 6.13-fold risk of death in these patients (P = 0.019). The number of tumors, nuclear grade, pTa stage, and the interaction between GI degree and nonmutated p53 gene remained in the Cox model for superficial tumors, such that these patients had a lower risk of recurrence or progression (P = 0.008). CONCLUSIONS: Alterations in the p53 gene may be indicative of poorer prognosis and greater recurrence in patients with urothelial bladder tumor, in particular, the presence of mutations in exon 8 and a greater percentage of stained cells in the immunohistochemistry. Nevertheless, the classic prognostic factors (primarily, pTNM stage) should still be considered the most useful factors for follow-up of these patients.


Assuntos
Carcinoma de Células de Transição/genética , Genes p53 , Mutação , Neoplasias da Bexiga Urinária/genética , Idoso , Carcinoma de Células de Transição/mortalidade , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Neoplasias da Bexiga Urinária/mortalidade
8.
Arch. esp. urol. (Ed. impr.) ; 61(1): 27-33, ene.-feb. 2008. ilus
Artigo em Es | IBECS | ID: ibc-059042

RESUMO

Objetivo: Revisar el diagnóstico y tratamiento actual de los tumores testiculares de células de Leydig, poniendo especial atención en el tratamiento conservador. Métodos: Presentamos dos casos de tumor de células de Leydig en adultos jóvenes, diagnosticados dos años después de aparecer ginecomastia bilateral como primera manifestación clínica. Resultados: al año y ocho meses respectivamente de efectuarse la orquiectomía, las manifestaciones clínicas desaparecieron totalmente en el primer caso y mejoraron ostensiblemente en el segundo. Conclusiones: Alrededor del 10% y sólo en adultos, estos tumores pueden ser malignos, siendo el tratamiento de elección la orquiectomía radical, aunque es posible la realización de cirugía conservadora. El seguimiento de estos pacientes, independientemente de la cirugía practicada, debe ser prolongado (AU)


Objectives: To review the current diagnosis and treatment of Leydig cell testicular tumors, with special attention to conservative treatment. Methods: We report two cases of Leydig cell tumor in young adults, diagnosed two years after the appearance of bilateral gynecomastia as first clinical symptom. Results: One year and eight months after orchyectomy, respectively, clinical symptoms completely disappear in the first case and significantly improved in the second. Conclusions: Around 10% of the cases, and only in adult patients, these tumors may be malignant, being radical orchyectomy the treatment of choice, although conservative surgery may be performed. Independently of the operation, follow-up must be prolonged (AU)


Assuntos
Masculino , Adulto , Humanos , Tumor de Células de Leydig/diagnóstico , Neoplasias Testiculares/diagnóstico , Tumor de Células de Leydig/cirurgia , Ginecomastia/etiologia , Ginecomastia/diagnóstico , Orquiectomia/métodos , Biomarcadores Tumorais , Neoplasias Testiculares/cirurgia
9.
Urol Int ; 79(4): 321-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18025850

RESUMO

OBJECTIVE: To analyze the correlation between the genotypic and phenotypic patterns of p53 in patients with transitional cell carcinoma (TCC) of the urinary bladder. MATERIALS AND METHODS: Cross-sectional study of 73 patients diagnosed with TCC. DNA was obtained from the tumor tissue to perform polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) of exons 5-9 of the p53 gene, with automatic sequencing done on any mutated samples. Immunohistochemistry (IHC) was also performed using anti-human P53 monoclonal antibody, and the diagnostic performance of this test was analyzed by a ROC curve, using the presence of p53 mutations found by PCR-SSCP as 'gold standard'. RESULTS: The cutoff point for defining immunopositivity was 20%. IHC had a specificity of 62.9%, and a sensitivity of 65.8%. The highest sensitivity values appeared in G3 tumors (75%) and infiltrating tumors (71.4%), and the highest specificity values were observed in G1 (77.7%) and G2 tumors (90%) and superficial tumors (66.6%). Mutations in exon 8 gave a positive result most frequently (73.7%) and were considered most relevant in terms of altering P53 function (60.9%). False negatives were documented in 28.5% of infiltrating tumors, and false positives in 33.4% of superficial tumors. CONCLUSIONS: There is a moderate correlation between p53 mutations and P53 protein overexpression, with this stronger in high-grade, infiltrating tumors, in exon 8 mutations, and when the mutation induces relevant changes in the protein structure. Although IHC is useful in routine clinical practice, the classic prognostic factors should still be considered the most important in the follow-up of these patients.


Assuntos
Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/patologia , Recidiva Local de Neoplasia/genética , Proteína Supressora de Tumor p53/genética , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Carcinoma de Células de Transição/mortalidade , Estudos Transversais , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Mutação , Estadiamento de Neoplasias , Polimorfismo Conformacional de Fita Simples , Probabilidade , Fatores de Risco , Sensibilidade e Especificidade , Análise de Sobrevida , Neoplasias da Bexiga Urinária/mortalidade
10.
Urology ; 70(1): 178.e7-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17656237

RESUMO

Isolated polyarteritis nodosa is a rare condition that may be triggered by local exposure to certain agents capable of provoking local immunostimulation without a systemic immune reaction. Isolated polyarteritis nodosa in the testes presents similar histologic characteristics as those of systemic inflammation, although infarcted areas in the testis are more common in generalized polyarteritis nodosa. Definitive diagnosis requires histologic study. We present the case of a 26-year-old patient with isolated testicular polyarteritis nodosa whose symptoms consisted predominantly of intense testicular pain and slight enlargement of both testes.


Assuntos
Poliarterite Nodosa/diagnóstico , Doenças Testiculares/diagnóstico , Adulto , Humanos , Masculino
11.
Int Urogynecol J Pelvic Floor Dysfunct ; 18(8): 949-54, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17361325

RESUMO

Bladder endometriosis is rare, although the bladder is the urinary tract structure most often affected by this condition. The common clinical manifestations of bladder endometriosis include menouria and urethral and pelvic pain syndrome occurring cyclically. Imaging methods are not conclusive for the definitive diagnosis. Cystoscopy is the most useful diagnostic test with confirmation by histologic study. Treatment must be individualized according to the patient's age, desire for future pregnancies, the severity of the symptoms, the site affected, and whether other organs are involved. Two types of treatment are currently used as follows: medical-hormonal and surgical.


Assuntos
Endometriose/diagnóstico , Endometriose/terapia , Doenças da Bexiga Urinária/diagnóstico , Doenças da Bexiga Urinária/terapia , Endometriose/etiologia , Feminino , Humanos , Doenças da Bexiga Urinária/etiologia
12.
Actas Urol Esp ; 30(3): 295-300, 2006 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-16749586

RESUMO

OBJECTIVES: To analyze the change in the behavior of renal cell carcinoma for its presentation, treatment, histology and mortality during a 17 year period. MATERIAL AND METHOD: Retrospective study on 212 patients diagnosed with renal cell carcinoma in our Department from the year 1988 up to 2004, analyzing the clinical and demographic data and comparing them to each other according to two periods: 1988-1996 and 1997-2004. RESULTS: An increase has been appreciated in the incidence of renal tumors in the second period and in a same way an increase in the incidental diagnosis and in the practice of nephron sparing surgery. Clear cell type was the most frequent in both periods and tumoral size was higher in the first period than in second. TNM stage I was the most frequent, although in first period it was higher percentage of stage IV. Cause-specific mortality has increased in the last years. CONCLUSION: An increase is appreciated in the incidence of renal cell tumors. Although the diagnosis is in earlier stages, a descent in the mortality has not been found.


Assuntos
Carcinoma de Células Renais/epidemiologia , Neoplasias Renais/epidemiologia , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/cirurgia , Feminino , Humanos , Incidência , Neoplasias Renais/diagnóstico , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
13.
Med. clín (Ed. impr.) ; 126(12): 452-454, abr. 2006. tab, graf
Artigo em Es | IBECS | ID: ibc-043904

RESUMO

Fundamento y objetivo: La metilación de los islotes CpG (secuencias del genoma ricas en guanina y citosina) presentes en las regiones promotoras constituye la forma de inactivación epigenética más común y es una alteración en el mecanismo de regulación de los genes que no requiere cambios en la secuencia del ADN. Se ha descrito hipermetilación del promotor del gen hMLH1 en algunas líneas celulares procedentes de carcinoma de células renales (CCR). Nuestro objetivo ha sido determinar la existencia de hipermetilación en el promotor del gen hMLH1 en muestras de ADN tumoral de pacientes con CCR esporádico. Material y método: Se recogieron consecutivamente 65 muestras de tejido tumoral procedente de pacientes diagnosticados de CCR. Tras la obtención y purificación del ADN se procedió a su digestión con las enzimas de restricción HpaII y MspI, seguido de amplificación mediante reacción en cadena de la polimerasa de 3 regiones del promotor del gen hMLH1, electroforesis en gel de agarosa y análisis densitométrico de las bandas amplificadas. Resultados: La edad media de los pacientes fue de 63,7 años. El tipo celular más frecuente fue el carcinoma de células claras (67,7%). Un 73,9% de los tumores se diagnosticaron en estadios inferiores a pT2, un 9,3% tenían afectación ganglionar y un 20%, metástasis a distancia. No se detectó hipermetilación somática en la región promotora del gen hMLH1 en ninguno de los pacientes estudiados. Conclusiones: La hipermetilación del promotor del gen hMLH1 no parece intervenir en la patogenia del CCR esporádico, y es necesario analizar la existencia de otro tipo de mutaciones, inestabilidad de microsatélites y/o pérdida de heterocigosis para determinar el posible papel de este gen en la patogenia del CCR esporádico


Background and objective: Epigenetic inactivation is a gene function abnormality that produces no changes in the DNA sequence, with the most frequent epigenetic alteration being hypermethylation of CpG islands in the promoter regions of the genes. Based on recent indications of a potential relationship between mismatch repair genes and renal cell carcinoma (RCC), we were interested in investigating the existence of promoter hypermethylation of the hMLH1 gene in tumor DNA samples from patients with sporadic RCC. Material and method: Sixty-five tumor tissue specimens were collected consecutively. The DNA was first obtained and purified, then digested with the restriction enzymes Hpa II and Msp I, followed by polimerase chain reaction amplification of 3 promoter regions of the hMLH1 gene, agarose gel electrophoresis, and densitometric analysis of the images of the amplified bands. Results: Mean patient age was 63.7 years. The most frequent cell type was clear cell carcinoma (67.7%). 73.9% of tumors were diagnosed in stages below pT2, 9.3% had gland involvement and 20%, distant metastasis. No somatic hypermethylation was detected in the promoter region of the hMLH1 gene in any of the patients studied. Conclusions: Our data indicate that promoter hypermethylation of the hMLH1 gene is not implicated in the pathogenesis of sporadic RCC, and therefore the existence of another type of mutation, microsatellite instability and/or loss of heterozygosity should be examined to determine the possible role of this gene in sporadic RCC


Assuntos
Masculino , Feminino , Pessoa de Meia-Idade , Humanos , Carcinoma de Células Renais/genética , Metilação de DNA , Neoplasias Renais/genética , Regiões Promotoras Genéticas/genética
14.
Med Clin (Barc) ; 126(12): 452-4, 2006 Apr 01.
Artigo em Espanhol | MEDLINE | ID: mdl-16620731

RESUMO

BACKGROUND AND OBJECTIVE: Epigenetic inactivation is a gene function abnormality that produces no changes in the DNA sequence, with the most frequent epigenetic alteration being hypermethylation of CpG islands in the promoter regions of the genes. Based on recent indications of a potential relationship between mismatch repair genes and renal cell carcinoma (RCC), we were interested in investigating the existence of promoter hypermethylation of the hMLH1 gene in tumor DNA samples from patients with sporadic RCC. MATERIAL AND METHOD: Sixty-five tumor tissue specimens were collected consecutively. The DNA was first obtained and purified, then digested with the restriction enzymes Hpa II and Msp I, followed by polimerase chain reaction amplification of 3 promoter regions of the hMLH1 gene, agarose gel electrophoresis, and densitometric analysis of the images of the amplified bands. RESULTS: Mean patient age was 63.7 years. The most frequent cell type was clear cell carcinoma (67.7%). 73.9% of tumors were diagnosed in stages below pT2, 9.3% had gland involvement and 20%, distant metastasis. No somatic hypermethylation was detected in the promoter region of the hMLH1 gene in any of the patients studied. CONCLUSIONS: Our data indicate that promoter hypermethylation of the hMLH1 gene is not implicated in the pathogenesis of sporadic RCC, and therefore the existence of another type of mutation, microsatellite instability and/or loss of heterozygosity should be examined to determine the possible role of this gene in sporadic RCC.


Assuntos
Carcinoma de Células Renais/genética , Proteínas de Transporte/genética , Neoplasias Renais/genética , Proteínas Nucleares/genética , Proteínas Adaptadoras de Transdução de Sinal , Pareamento Incorreto de Bases , Metilação de DNA , Reparo do DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Regiões Promotoras Genéticas
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