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1.
Mol Cell Biol ; 23(4): 1470-6, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12556505

RESUMEN

Mutations in either the Drosophila melanogaster pelota or pelo gene or the Saccharomyces cerevisiae homologous gene, DOM34, cause defects of spermatogenesis and oogenesis in Drosophila, and delay of growth and failure of sporulation in yeast. These phenotypes suggest that pelota is required for normal progression of the mitotic and meiotic cell cycle. To determine the role of the pelota in mouse development and progression of cell cycle, we have established a targeted disruption of the mouse PELO: Heterozygous animals are variable and fertile. Genotyping of the progeny of heterozygous intercrosses shows the absence of Pelo(-/-) pups and suggests an embryo-lethal phenotype. Histological analyses reveal that the homozygous Pelo deficient embryos fail to develop past day 7.5 of embryogenesis (E7.5). The failure of mitotic active inner cell mass of the Pelo(-/-) blastocysts to expand in growth after 4 days in culture and the survival of mitotic inactive trophoplast indicate that the lethality of Pelo-null embryos is due to defects in cell proliferation. Analysis of the cellular DNA content reveals the significant increase of aneuploid cells in Pelo(-/-) embryos at E7.5. Therefore, the percent increase of aneuploid cells at E7.5 may be directly responsible for the arrested development and suggests that Pelo is required for the maintenance of genomic stability.


Asunto(s)
Ciclo Celular/genética , Muerte Fetal/genética , Animales , Blastocisto/fisiología , Ingeniería Genética/métodos , Ratones , Ratones Mutantes , Mitosis , Mutación , Células Madre/fisiología
2.
Anticancer Res ; 27(1A): 283-8, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17352245

RESUMEN

Overexpression of p16 has been demonstrated to be strongly related to the presence of HPV16, 18. Squamous cell carcinoma of the head and neck has been shown to be associated with human papillomavirus (HPV) infection. The main aim of this study was to investigate the relationship between HPV presence and p16 expression in a representative collection of 60 head and neck carcinomas by tissue microarrays. The presence of HPV (HPV6, 11-low risk, HPV16, 18-high risk) was detected by applying in situ hybridisation. P-16 protein expression was detected immunohistochemically. HPV6, 11 positivity was observed in 10 out of 60 carcinomas. HPV16, 18 presence was found in 30 out of 60 tumours. P-16 expression was detected in 35 out of 60 tumours. A statistically significant relationship was demonstrated between HPV16, 18 presence and increased expression of p16. Also the HPV6, 11 presence was significantly correlated with p16 immunoreactivity. Additionally, this study demonstrates that it is possible to analyse p16 expression and HPV presence by tissue microarrays.


Asunto(s)
Alphapapillomavirus/aislamiento & purificación , Carcinoma de Células Escamosas/virología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/biosíntesis , Neoplasias Laríngeas/virología , Neoplasias de la Boca/virología , Infecciones por Papillomavirus/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/metabolismo , Femenino , Papillomavirus Humano 11/aislamiento & purificación , Papillomavirus Humano 16/aislamiento & purificación , Papillomavirus Humano 18/aislamiento & purificación , Humanos , Inmunohistoquímica , Hibridación in Situ , Neoplasias Laríngeas/metabolismo , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/metabolismo , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/virología , Análisis de Matrices Tisulares
3.
Hum Pathol ; 37(4): 448-52, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16564919

RESUMEN

Ku70 and Ku80 proteins take part in the repairing of DNA double-strand breaks by their function as a regulatory subunit of the DNA-dependent protein kinase. In this study, expression of both genes was analyzed in colorectal carcinoma tissue arrays applying immunohistochemistry. Expression of both genes decreased along with pT stage. Significant differences in Ku70 and Ku80 expression were found between pT3 and pT4 as well as between pT2 and pT3 tumors, respectively. Loss of Ku70/Ku80 expression was more frequently observed in hereditary than in sporadic tumors. We conclude that expression of Ku70/Ku80 genes is down-regulated in colorectal carcinoma and that defects of these genes are more frequently observed in hereditary than in sporadic tumors.


Asunto(s)
Antígenos Nucleares/metabolismo , Neoplasias Colorrectales Hereditarias sin Poliposis/metabolismo , Proteínas de Unión al ADN/metabolismo , Análisis de Matrices Tisulares/métodos , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Estudios de Cohortes , Neoplasias Colorrectales Hereditarias sin Poliposis/patología , Reparación del ADN , Regulación hacia Abajo , Femenino , Humanos , Autoantígeno Ku , Masculino , Persona de Mediana Edad
4.
Anticancer Res ; 26(3A): 2107-12, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16827152

RESUMEN

Alterations of DNA mismatch repair genes, primarily demonstrated in hereditary nonpolyposis colorectal carcinomas, were reported to be of relevance for the progression of several sporadic tumours. In this study, the expression and mutations of MLH1, MSH2, PMS1 and PMS2 in a panel of thyroid tumours, including nodular hyperplasia, follicular adenomas and carcinomas, were investigated. The expressions of MLH1, MSH2 and PMS1 were generally higher in malignant tumours than in benign lesions (p < 0.01). This observation can find potential diagnostic application in the differentiation of follicular adenomas from follicullar carcinomas of the thyroid. No point mutations in the DNA mismatch repair genes MSH2 (exon 12, 13) and MLH1 (exon 15, 16) were found.


Asunto(s)
Disparidad de Par Base , Reparación del ADN/genética , Mutación , Neoplasias de la Tiroides/genética , Proteínas Adaptadoras Transductoras de Señales , Adenocarcinoma Folicular/genética , Adenocarcinoma Folicular/metabolismo , Adenocarcinoma Folicular/patología , Adenoma/genética , Adenoma/metabolismo , Adenoma/patología , Adenosina Trifosfatasas/biosíntesis , Adenosina Trifosfatasas/genética , Adolescente , Adulto , Anciano , Secuencia de Bases , Carcinoma Papilar/genética , Carcinoma Papilar/metabolismo , Carcinoma Papilar/patología , Proteínas Portadoras/biosíntesis , Proteínas Portadoras/genética , Enzimas Reparadoras del ADN/biosíntesis , Enzimas Reparadoras del ADN/genética , Proteínas de Unión al ADN/biosíntesis , Proteínas de Unión al ADN/genética , Femenino , Expresión Génica , Humanos , Hiperplasia , Masculino , Persona de Mediana Edad , Endonucleasa PMS2 de Reparación del Emparejamiento Incorrecto , Datos de Secuencia Molecular , Homólogo 1 de la Proteína MutL , Proteínas MutL , Proteína 2 Homóloga a MutS/biosíntesis , Proteína 2 Homóloga a MutS/genética , Invasividad Neoplásica , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Proteínas Nucleares/biosíntesis , Proteínas Nucleares/genética , Glándula Tiroides/patología , Neoplasias de la Tiroides/metabolismo , Neoplasias de la Tiroides/patología
5.
Anticancer Res ; 26(2A): 1231-5, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16619529

RESUMEN

The mutations of MLH1 and MSH2 have been reported to be responsible for malignant transformation and tumour progression in several sporadic tumours. Eighty-six primary malignant melanomas with known follow-up were investigated. Point mutations of DNA mismatch repair MLH1 and MSH2 in malignant melanomas were not found. Exon 12 (MSH2) was not present in 26 out of the 86 melanomas and exon 13 (MSH2) was lost in 25 of the tumours. The loss of exon 15 (MLH1) was observed in 22 out of the 86 tumours and the loss of exon 16 (MLH1) in 24 melanomas. The loss of exons correlated strongly with the loss of MLH1 and MSH2 protein expression. In multivariate analysis, including all 4 exons and expressions of MLH1 and MSH2, prognostic significance was found only for loss of exon 12 (MSH2) and loss of exon 15 (MLH1).


Asunto(s)
Proteínas Portadoras/genética , Reparación del ADN/genética , Melanoma/genética , Proteína 2 Homóloga a MutS/genética , Proteínas Nucleares/genética , Proteínas Adaptadoras Transductoras de Señales , Disparidad de Par Base , Proteínas Portadoras/biosíntesis , Exones , Eliminación de Gen , Humanos , Melanoma/metabolismo , Homólogo 1 de la Proteína MutL , Proteína 2 Homóloga a MutS/biosíntesis , Proteínas Nucleares/biosíntesis , Mutación Puntual , Pronóstico , Modelos de Riesgos Proporcionales , Tasa de Supervivencia
6.
Anticancer Res ; 26(3A): 2101-5, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16827151

RESUMEN

The relevance of double-strand DNA repair genes has been demonstrated in several tumours. The main aim of this study was to analyse the expression of the heterodimers Ku70 and Ku80, building regulatory subunits of the DNA-dependent protein kinase in 40 oral carcinomas. Ku70 expression was found in 87.5% of grade 1 and grade 3 tumours and in 82.9% of grade 2 carcinomas. Ku80 presence was noted in 87.5% of grade 1 tumours, 82.9% of grade 2 tumours and in all grade 3 tumours. Ku70-positive cells were present in 90.5% of tumours without and in 80% of tumours with lymphatic metastases. A similar relationship was found for Ku80 expression. Additionally, the expression of Ku70 was highly significantly related to smoking habits. Our results demonstrated that defects of DNA double-strand repair genes play an important role in the tumour progression of oral carcinomas.


Asunto(s)
Antígenos Nucleares/genética , Carcinoma de Células Escamosas/genética , Reparación del ADN/genética , Proteínas de Unión al ADN/genética , Neoplasias de la Boca/genética , Adulto , Anciano , Anciano de 80 o más Años , Antígenos Nucleares/biosíntesis , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , ADN de Neoplasias/genética , Proteínas de Unión al ADN/biosíntesis , Femenino , Humanos , Autoantígeno Ku , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Estadificación de Neoplasias , Fumar/genética , Fumar/metabolismo
7.
Anticancer Res ; 26(5A): 3461-5, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17094467

RESUMEN

Recent reports indicate that the alterations in the p16 and pRb pathways can influence tumour progression and poor prognosis in several tumours. The objective of this study was to analyse p16 and pRb expression in161 patients with malignant fibrous histiocytomas (MFH). By immunohistochemistry, p16 and pRb were demonstrated in 25% and 56% of MFH, respectively. Cox regression analysis demonstrated an independent prognostic influence of both genes. Generally, the loss of p16 and pRb expression correlated with poorer prognosis. Promoter methylation of p16 was found in 16/42 of p16 negative MFH and of pRb in 2/42 of pRb-negative MFH. It can be concluded that p16 and pRb alterations play an important role in the progression of soft tissue sarcomas.


Asunto(s)
Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Metilación de ADN , Histiocitoma Fibroso Maligno/genética , Histiocitoma Fibroso Maligno/metabolismo , Regiones Promotoras Genéticas/genética , Proteína de Retinoblastoma/metabolismo , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Humanos , Técnicas para Inmunoenzimas , Pronóstico , Proteína de Retinoblastoma/genética , Transducción de Señal
8.
Anticancer Res ; 25(6B): 4293-8, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16309231

RESUMEN

The proposed grading system for malignant fibrous histiocytomas (MFH) comprises 3 grades of malignancy. Analogous to other grading systems, the system includes the factors of mitotic rate and necrosis. In addition to these two factors, the concept of cellularity was included. The prognostic relevance of the grading systems published by Costa, Coindre, van Unnik, Pezzi and Tsujimoto as well as the grading system proposed by the present study was tested on 161 MFH. The results showed that all grading systems tested produced clearly significant differences (p < 0.01) with regard to the survival estimated for patients with various grades of malignancy. These results revealed the superiority of systems that use 3 grades of malignancy over a 2-grade classification. The proposed grading system yielded a lower percentage of grade II tumours (37%) than the grading systems of Coindre (60%) and van Unnik (70%). In the multivariate analysis of all grading systems, the proposed grading system was the only one to show prognostic relevance (p < 0. 05).


Asunto(s)
Histiocitoma Fibroso Maligno/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico
9.
Anticancer Res ; 25(4): 2789-92, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16080528

RESUMEN

It has been postulated that the high malignancy of melanomas could be connected with an increased cytokeratin (CK) expression. In order to define the relationship between CK expression and genetic instability of melanoma metastases, ploidy-related parameters were compared in cytological specimens of CK-positive and CK-negative melanoma metastases. CK expression was investigated immunohistochemically in 35 melanoma liver metastases and in 52 melanoma lymphatic metastases. Ploidy-related parameters were evaluated on Feulgen-stained specimens with a CAS200 image analyzer. Cytokeratin was detected in 14 out of 35 melanoma liver metastases and in 24 out of 52 melanoma lymphatic metastases investigated. Significant differences between CK-positive and CK-negative melanoma metastases were found for the percentage of diploid cells, percentage of tetraploid cells, percentage of aneuploid cells between 4c and 8c, as well as for 5c exceeding rate. Our results confirmed that CK is present in more advanced (unstable), clearly aneuploid forms of melanoma metastases.


Asunto(s)
Aneuploidia , Queratinas/biosíntesis , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundario , Melanoma/genética , Melanoma/secundario , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Inestabilidad Genómica , Humanos , Queratinas/genética , Neoplasias Hepáticas/metabolismo , Metástasis Linfática , Masculino , Melanoma/metabolismo , Persona de Mediana Edad
10.
In Vivo ; 19(6): 1093-6, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16277028

RESUMEN

Twenty-nine cases of oral melanomas were investigated for nm23 and Ki67 antigen expression, as well as for the fraction of tumour cells in S-phase, using immunohistochemical techniques and DNA cytophotometry. Nm23 expression was significantly reduced and Ki67 antigen expression increased in primary tumours with either lymph node or organ metastases in comparison to tumours without metastases. The percentages of Ki67 immunoreactive tumour cells and cells in S-phase correlated positively with each other and negatively with the percentage of nm23-expressing cells. These data argue against a significant growth stimulatory function of the nm23H1 gene product nucleoside diphopshate kinase in the progression of oral melanomas. The functional relevance of nm23 in relation to increased proliferation and metastatic spread is discussed.


Asunto(s)
Biomarcadores de Tumor/análisis , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Melanoma/diagnóstico , Melanoma/enzimología , Neoplasias de la Boca/diagnóstico , Neoplasias de la Boca/enzimología , Nucleósido-Difosfato Quinasa/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Citofotometría , ADN/análisis , Femenino , Genes Relacionados con las Neoplasias , Humanos , Inmunohistoquímica , Antígeno Ki-67/análisis , Metástasis Linfática , Masculino , Melanoma/genética , Melanoma/metabolismo , Melanoma/patología , Melanoma/cirugía , Persona de Mediana Edad , Neoplasias de la Boca/genética , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Neoplasias de la Boca/cirugía , Nucleósido Difosfato Quinasas NM23 , Metástasis de la Neoplasia , Nucleósido-Difosfato Quinasa/genética , Pronóstico , Fase S
11.
Hum Pathol ; 35(2): 210-6, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14991539

RESUMEN

Ku70 and Ku80 proteins are responsible for the repair of DNA double-strand breaks and function as a regulatory subunit of the DNA-dependent protein kinase. In this study we analyzed expression of both genes in malignant melanoma tissue arrays applying in situ hybridization probes produced by our research group and using immunohistochemical analysis. Expression of both genes was down-regulated as melanoma progressed. In situ hybridization demonstrated more Ku70- and Ku80-positive cells than immunohistochemical methods, but the correlation between the two methods was highly significant (P <0.01). We conclude that the in situ hybridization assay for the detection of Ku70 and Ku80 expression used in this study is also suitable for tissue microarray analysis of paraffin-embedded melanoma samples. The laboratory procedure is much more complicated than the immunohistochemical method, however.


Asunto(s)
Antígenos Nucleares/análisis , Biomarcadores de Tumor/análisis , ADN Helicasas , Proteínas de Unión al ADN/análisis , Inmunohistoquímica , Hibridación in Situ/métodos , Melanoma/química , Melanoma/patología , Análisis por Matrices de Proteínas , Adulto , Anciano , Anciano de 80 o más Años , Reparación del ADN , Regulación hacia Abajo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Autoantígeno Ku , Masculino , Melanoma/genética , Persona de Mediana Edad , Estadificación de Neoplasias , Parafina , Reacción en Cadena de la Polimerasa , Sondas ARN , ARN Complementario/análisis , ARN Neoplásico/análisis , Neoplasias Cutáneas/química , Neoplasias Cutáneas/patología
12.
Hum Pathol ; 35(7): 887-91, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15257554

RESUMEN

A new high-throughput tissue-arraying technique, now frequently used in tumor pathology, requires standardization of methods of DNA analysis, previously applied in full histological sections. The main objectives of this study were to evaluate DNA ploidy status and DNA ploidy-related parameters using the CAS200 image analyzer in malignant melanoma tissue microarrays and to compare them with full histological sections. Comparison of DNA ploidy-related parameters, including percentage of diploid cells, percentage of aneuploid cells between 2c and 4c, percentage of tetraploid cells, percentage of aneuploid cells between 4c and 8c, percentage of octaploid cells, percentage of 16-ploid cells, and 5c exceeding rate, did not reveal any significant differences between malignant melanoma tissue microarrays and full sections. The DNA ploidy status according to Auer differed in 1 out of 59 cases investigated. Our study demonstrated that it is possible to evaluate DNA ploidy status and DNA ploidy-related parameters in tissue microarrays, which is of practical relevance to tumor pathology.


Asunto(s)
ADN de Neoplasias/análisis , Citometría de Imagen/métodos , Melanoma/genética , Ploidias , Análisis por Matrices de Proteínas , Neoplasias Cutáneas/genética , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Melanoma/patología , Persona de Mediana Edad , Colorantes de Rosanilina , Neoplasias Cutáneas/patología
13.
Hum Pathol ; 35(12): 1543-8, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15619215

RESUMEN

Defects in DNA mismatch-repair genes MLH1 and MSH2 reported primarily in hereditary nonpolyposis colorectal carcinoma are present in many sporadic tumors, including malignant melanomas. The main aim of this study was to investigate the expression of these genes in malignant melanomas in relation to tumor stage. An experiment was performed on paraffin-embedded tissue microarrays of malignant melanomas applying in situ hybridization with probes produced by our research group and immunohistochemical techniques. In situ hybridization demonstrated MLH1 expression in 45 of 59 melanomas and MSH2 expression in 51 of 59 melanomas. Immunohistochemistry detected MLH1 expression in 46 of 59 melanomas and MSH2 expression in 50 of 59 melanomas. Down-regulation of expression of both DNA mismatch repair genes in malignant melanomas was observed. The findings obtained by in situ hybridization and immunohistochemistry correlated significantly. Our study demonstrates the suitability of in situ hybridization with MLH1 and MSH2 probes for paraffin-embedded tissue. Tissue microarrays can be used successfully in both in situ hybridization and immunohistochemistry to analyze the expression of DNA mismatch-repair genes.


Asunto(s)
Proteínas de Unión al ADN/genética , Hibridación in Situ/métodos , Melanoma/genética , Proteínas de Neoplasias/genética , Análisis por Matrices de Proteínas , Proteínas Proto-Oncogénicas/genética , Neoplasias Cutáneas/genética , Proteínas Adaptadoras Transductoras de Señales , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Proteínas Portadoras , Proteínas de Unión al ADN/metabolismo , Femenino , Humanos , Inmunohistoquímica , Masculino , Melanoma/metabolismo , Melanoma/patología , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL , Proteína 2 Homóloga a MutS , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares , Proteínas Proto-Oncogénicas/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Adhesión del Tejido/métodos
14.
Int J Mol Med ; 14(5): 825-36, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15492852

RESUMEN

Transitional cell carcinomas (TCC) of the urinary bladder develop by a multistep process characterized by various stages of transformation differing in their grade of malignancy and biological behaviour. Since the prospective clinical outcome cannot be reliably predicted on histopathological grounds, we analysed the mRNA expression of the MDM2-p73-P14ARF tumour surveillance pathway in an attempt to detect alterations of gene activity, allowing a better understanding of the mechanisms responsible for conversion of low to high malignant TCC. Expression of the mRNA was determined in 71 TCC of various grades and stages using the real-time quantitative reverse transcription-polymerase chain reaction. The MDM2-p73-P14ARF pathway was dominated by the MDM2 gene, the mRNA expression of which proved to be significantly (5-fold) lower in advanced high-grade, high-stage than in superficial low-grade, low-stage TCC. Conversely, the expression of p73 mRNA increased with increasing tumour grades and stages, while the activity of the P14ARF gene was not substantially altered during early and late phases of urothelial carcinogenesis. Analysing the expression of spliced variants of MDM2 mRNA, we found a heterogeneous pattern including a novel splicing transcript coding for an abnormal protein. Promoter hypermethylation of P14ARF occurred in 10% of the TCC with an under-expression of mRNA. An analysis of the effects of lifestyle and occupational bladder cancer risk factors revealed that TCC of smokers showed a 2-fold elevated expression of MDM2 mRNA and an approximately 2-fold lower expression of P14ARF mRNA, whereas the activity of the p73 gene was unchanged. Heavy coffee consumption was associated with a 2-fold decreased expression level of P14ARF mRNA. Exposure to certain occupational hazards (plastic products, paints and lacquer, polycyclic hydrocarbons, chemical solvents) was observed to modulate the activity of the genes analysed. Our findings suggest that an alteration in the MDM2-p73-P14ARF pathway is involved in the progression of bladder cancer to a more malignant and aggressive form.


Asunto(s)
Proteínas de Unión al ADN/genética , Proteínas Nucleares/genética , Proteínas Proto-Oncogénicas/genética , Proteína p14ARF Supresora de Tumor/genética , Neoplasias de la Vejiga Urinaria/patología , Secuencia de Bases , Carcinoma de Células Transicionales/genética , Carcinoma de Células Transicionales/patología , Café , Cartilla de ADN , Progresión de la Enfermedad , Exones/genética , Regulación Neoplásica de la Expresión Génica , Genes Supresores de Tumor , Humanos , Datos de Secuencia Molecular , Exposición Profesional , Proteínas Proto-Oncogénicas c-mdm2 , Empalme del ARN , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Riesgo , Fumar , Proteína Tumoral p73 , Proteínas Supresoras de Tumor , Neoplasias de la Vejiga Urinaria/genética
15.
Int J Mol Med ; 10(6): 707-11, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12429996

RESUMEN

p63 is a known homologue of p53. In contrast to p53, however, p63 mutations are rarely seen in tumours. There have been several reports that p63 plays a regulatory role in the normal differentiation of cells, whereas its role in tumour biology must still be elucidated. The main aim of this study was to compare p63 and p53 expression in tissue microarrays of malignant melanomas and to establish any prognostic significance. p63 expression was found in 2 out of 59 tumours, both pT4. The p63 index did not exceed 30%. p53 expression was found in 27 out of 59 melanomas, with maximal expression in up to 80% of tumour cells. There were no correlations observed between the two markers. Multivariate analysis confirmed the prognostically independent role of p53. This study also confirmed that tissue microarrays can be used effectively for evaluation of the expression of certain tumour markers.


Asunto(s)
Melanoma/metabolismo , Proteínas de la Membrana , Fosfoproteínas/genética , Transactivadores/genética , Proteína p53 Supresora de Tumor/genética , Adulto , Anciano , Anciano de 80 o más Años , Proteínas de Unión al ADN , Femenino , Genes Supresores de Tumor , Humanos , Masculino , Melanoma/genética , Persona de Mediana Edad , Fosfoproteínas/metabolismo , Transactivadores/metabolismo , Factores de Transcripción , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Supresoras de Tumor
16.
Anticancer Res ; 24(6): 4191-4, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15736472

RESUMEN

Differential diagnostics of borderline ovarian tumours and ovarian carcinomas is generally based on morphological criteria, which are not always sufficient for final diagnosis. Therefore, we investigated the practical diagnostic application of the CAS200 image analyzer and new ploidy-related parameters in a series of 68 borderline tumours and 42 low-grade carcinomas of the ovary. Highly significant differences between borderline and malignant lesions were found for the percentage of diploid cells (p = 0.0001), the percentage of aneuploid cells between 4c and 8c (p = 0.0001), the percentage of octaploid cells (p = 0.0001), as well as for the 5c exceeding rate (p = 0.0001). The difference concerning the ratio of tetraploid cells also reached the level of significance (p = 0.0320). We suggest that new ploidy-related parameters evaluated by the CAS200 image analyzer can be helpful in ovarian lesions with unclear morphology.


Asunto(s)
Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/genética , Ploidias , Adulto , Anciano , Anciano de 80 o más Años , ADN de Neoplasias/genética , ADN de Neoplasias/metabolismo , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/patología
17.
Anticancer Res ; 24(6): 3819-29, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15736417

RESUMEN

Soft tissue sarcomas frequently carry p53 mutations reducing chemotherapeutical response. Especially malignant fibrous histiocytoma (MFH) reveals a reduced ifosfamide (IF) chemosensitivity when compared to other sarcoma entities. This is the first study to analyze MFH cells for the effects of IF on the expression of the pathways P16-CDK4-Rb and P14ARF-MDM2-P73 regulating cell cycle. The aim was to identify candidate genes possibly involved in the anti-apoptotic response of p53-deficient MFH cells during chemotherapy. PCR, real-time RT-PCR and confocal laser scanning microscopy were applied on primary cultures of MFH cells containing defective p53 genes. The cultures were treated with different concentrations of IF. A non-treated MFH culture served as negative control. A threshold concentration of IF (100 microM) was determined sparing the majority of the cells (99%), whereas higher IF quantities caused complete apoptosis. Data collected over a period of 48 h showed that the MFH cells surviving 100 microM IF overexpressed the kinase gene CDK4 and oncogene MDM2 by a factor of 63. A similar strong increase was observed at the protein level for both proteins. In contrast, the other proteins analyzed were not detectable. Additionally, the MFH cells induced complex patterns of MDM2 mRNA splicing and an abnormal mRNA transcript carrying a novel MDM2 missense mutation. These effects were neither observed in the non-treated culture nor in cultures completely inducing spontaneous apoptosis. Therefore, we speculate that the induction of the gene CDK4, and especially of MDM2, is involved in anti-apoptotic mechanisms of p53-negative MFH cells tolerating IF in vitro. Further experiments are necessary to test whether the novel candidate genes favor development of chemoresistance and whether MDM2 mRNA splicing variants contribute to this process in vivo.


Asunto(s)
Antineoplásicos Alquilantes/farmacología , Histiocitoma Fibroso Benigno/tratamiento farmacológico , Histiocitoma Fibroso Benigno/genética , Ifosfamida/farmacología , Proteína p53 Supresora de Tumor/deficiencia , Actinas/biosíntesis , Actinas/genética , Empalme Alternativo/efectos de los fármacos , Caspasa 3 , Caspasas/metabolismo , Quinasa 4 Dependiente de la Ciclina , Inhibidor p16 de la Quinasa Dependiente de Ciclina/biosíntesis , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Quinasas Ciclina-Dependientes/biosíntesis , Quinasas Ciclina-Dependientes/genética , Proteínas de Unión al ADN/biosíntesis , Proteínas de Unión al ADN/genética , Genes Supresores de Tumor , Histiocitoma Fibroso Benigno/metabolismo , Humanos , Proteínas Nucleares/biosíntesis , Proteínas Nucleares/genética , Proteínas Proto-Oncogénicas/biosíntesis , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-mdm2 , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Proteína de Retinoblastoma/biosíntesis , Proteína de Retinoblastoma/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas , Proteína Tumoral p73 , Proteína p14ARF Supresora de Tumor/biosíntesis , Proteína p14ARF Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/genética , Proteínas Supresoras de Tumor
18.
Anticancer Res ; 24(2B): 981-6, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15161053

RESUMEN

Brain metastases, including those of malignant melanoma (known for its high genomic instability), are the most common intracranial tumors. The main objective of this study was to investigate expression and mutation in the DNA mismatch repair system in melanoma brain metastases. Expression of MLH1, MSH2, PMS1 and PMS2 was investigated immunohistochemically in 31 melanoma metastatic tumors. Mutational analysis of MLH1 and MSH2 was performed in 17 melanoma brain metastases. Loss of MLH1 and MSH2 expression was found in 10/31 and 12/31 tumors. PMS1 (27/31) and PMS2 (28/31) expression was preserved in the majority of lesions. Potential missense mutation was found in MSH2 (exon 13) in 2/17 melanomas. Mutation in the intron sequence between exon 14 and 15 of MLH1 (exon 15) was observed in 4/17 cases. Our results indicate that the two major DNA mismatch repair genes, MLH1 and MSH2, are more frequently affected by alterations in the DNA mismatch repair system than the helper genes PMS1 and PMS2. The presence of mutations of MSH2 and MLH1 in melanoma brain metastases, which has not been found in primary melanomas, indicates the high genomic instability of melanoma brain metastases.


Asunto(s)
Disparidad de Par Base , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundario , Reparación del ADN/genética , Proteínas de Unión al ADN/genética , Melanoma/genética , Melanoma/secundario , Mutación , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogénicas/genética , Proteínas Adaptadoras Transductoras de Señales , Adulto , Anciano , Neoplasias Encefálicas/metabolismo , Proteínas Portadoras , Proteínas de Unión al ADN/biosíntesis , Femenino , Expresión Génica , Inestabilidad Genómica/genética , Humanos , Inmunohistoquímica , Masculino , Melanoma/metabolismo , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL , Proteína 2 Homóloga a MutS , Proteínas de Neoplasias/biosíntesis , Proteínas Nucleares , Proteínas Proto-Oncogénicas/biosíntesis
19.
Anticancer Res ; 24(2B): 1011-23, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15161057

RESUMEN

Based on the concept that tumor suppressor genes are involved in the pathogenesis of urinary bladder carcinogenesis, we analysed the mRNA expression of the retinoblastoma (Rb) and p16 (CDKN2, INK4A, MTS1) genes as well as of the proto-oncogene cyclin D-dependent kinase 4 (CDK4) in 71 transitional cell carcinomas (TCC) of the urinary bladder in relation to the tumor grades and stages, and with reference to certain lifestyle and occupational risk factors. Using real-time quantitative reverse transcription-polymerase chain reaction, high-stage muscle invasive TCC expressed the Rb, p16 and CDK4 mRNA at lower levels than low-stage superficial cancers, indicating down-regulation to be linked with tumor progression. The drop of the expression in the group of grade 2 TCC when invading the muscle layer compared to grade 2 carcinomas with a superficial pattern of growth is considered to represent a key event in promoting urothelial carcinogenesis in this subset of carcinomas. The protein expression of the Rb gene evaluated by immunohistochemistry proved to be closely related to the tumor grades and stages as well as to the mRNA expression, high-grade and high-stage TCC disclosing a lower rate of positive immunoreactivity than low-grade and low-stage carcinomas. The p16 protein product was expressed at a lower level in grade 3 than in grade 1 TCC, but there was no correlation with the tumor stages or the mRNA expression. TCC with loss of heterozygosity (LOH) at the INK4A region showed a decreased expression of p16 mRNA compared to those without an allelic loss. Tobacco smoke was not identified to substantially modulate the Rb/p16/CDK4 pathways, except for a ten-fold elevated mRNA expression of the p16 gene in TCC of light compared to heavy smokers. Heavy coffee consumption was associated with a reduced expression of CDK4 mRNA. Among occupational exposures, TCC of patients in contact with stone dust, paints and lacquer, plastics, wood and wood preservers and chemical solvents and adhesives displayed altered partly elevated, partly reduced levels of Rb, p16 and CDK4 mRNA compared to non-exposed subjects. Although the underlying molecular-genetic pathways are not yet fully understood, the current results suggest functional reduction of the tumor suppressor genes Rb and p16 to be associated with progression of bladder cancer to a more malignant and aggressive behaviour.


Asunto(s)
Carcinoma de Células Transicionales/genética , Quinasas Ciclina-Dependientes/genética , Genes p16/fisiología , Proteínas Proto-Oncogénicas , ARN Mensajero/biosíntesis , Proteína de Retinoblastoma/genética , Neoplasias de la Vejiga Urinaria/genética , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Transicionales/metabolismo , Carcinoma de Células Transicionales/patología , Quinasa 4 Dependiente de la Ciclina , Quinasas Ciclina-Dependientes/biosíntesis , Progresión de la Enfermedad , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Exposición Profesional , Proto-Oncogenes Mas , ARN Mensajero/genética , Proteína de Retinoblastoma/biosíntesis , Factores de Riesgo , Fumar , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patología
20.
Anticancer Res ; 24(5B): 3203-7, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15510611

RESUMEN

The unclear role of cytokeratin (CK) in the progression and diagnostics of malignant melanomas stimulated us to compare the reactivity of three antibodies directed to CK in 109 paraffin-embedded melanomas. By far the majority of melanomas did not express cytokeratin even at the<1% level, only vimentin. In about 6% of melanomas it was possible to find CK expression ranging between 3 and 40% of melanoma cells. There was a correlation between CK expression and pT-stage. Cytokeratin-expressing tumours were found in the more advanced pT-stages. The independent prognostic values of none of the three CK antibodies investigated could be shown.


Asunto(s)
Anticuerpos Monoclonales/química , Queratinas/biosíntesis , Melanoma/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos , Femenino , Humanos , Inmunohistoquímica , Queratinas/inmunología , Masculino , Melanoma/patología , Persona de Mediana Edad , Estadificación de Neoplasias , Adhesión en Parafina , Pronóstico
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