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 SeñalRESUMEN
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/metabolismoRESUMEN
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 , PronósticoRESUMEN
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.
