| Journal: | Jornal brasileiro de patologia e medicina laboratorial |
| Database: | PERIÓDICA |
| System number: | 000297320 |
| ISSN: | 1676-2444 |
| Authors: | Faria, Mario Henrique Girao1 Patrocinio, Regia Maria do Socorro Vidal do2 Moraes-Filho, Manoel Odorico de Rabenhorst, Silvia Helena Barem |
| Institutions: | 1Universidade Federal do Ceara, Laboratorio de Genética Molecular, Fortaleza, Ceara. Brasil 2Universidade Federal do Ceara, Faculdade de Medicina, Fortaleza, Ceara. Brasil |
| Year: | 2006 |
| Season: | Ago |
| Volumen: | 42 |
| Number: | 4 |
| Pages: | 271-278 |
| Country: | Brasil |
| Language: | Portugués |
| Document type: | Artículo |
| Approach: | Caso clínico, analítico |
| English abstract | BACKGROUND: Astrocytomas represent the most frequent primary tumors of the central nervous system. Admittedly, part of tumor growth is due to inhibition of programmed cell death: the apoptosis. This phenomenon is basically regulated by the balance between anti-apoptotic (e.g.: B-cell lymphoma protein 2 [BCL-2]) and pro-apoptotic (e.g.: BCL-2 associated protein X [BAX]) molecules. OBJECTIVE: The present study aimed to evaluate the expression of BCL-2 and BAX in human astrocytic tumors of different histopathological grades. MATERIAL AND METHOD: An immunohistochemical study of those proteins using the avidin-biotin-peroxidase method was performed in 55 astrocytomas (13 grade I, 14 grade II, seven grade III and 21 grade IV) and five samples of non-tumor brain tissue (control group). RESULTS: The BCL-2 and BAX positive indices tended to increase according to astrocytomas graduation, with general positivity of 43.26% and 24.67%, respectively. These proteins were not detected among non-tumor specimens. BCL-2 labeling scores demonstrated a tendency to increase in accordance with histopathological advancing, while BAX values were similar in all graduations. The combined analyses of these proteins expression presents a significant correlation with tumor grade (p < 0.05; H test), witch is more evident among glioblastomas (grade IV) in comparison with low-grade astrocytomas (I and II) (p < 0.05; U test). BCL-2/BAX ratio denoted increasing of cellular survival orientation of the astrocytic tumors according to malignant progression. CONCLUSIONS: The results indicate alterations in BCL-2 and BAX proteins expression as resultant of the tumorigenic process in astrocytomas, with increasing predominance of the anti-apoptotic profile in consonance of malignant transformation. In this way, we propose that BCL-2 overexpression in astrocytic tumors may be indicative of more aggressive phenotypes, furthermore configuring a potential therapeutic target |
| Portuguese abstract | A relação BCL-2/BAX indicou o aumento da orientação à sobrevida celular dos tumores astrocíticos de acordo com a progressão maligna. CONCLUSÕES: Tais resultados indicam as alterações na expressão das proteínas BCL-2 e BAX como resultantes do processo tumorigênico nos astrocitomas, com o crescente predomínio do perfil antiapoptótico de acordo com a transformação maligna. Nesse sentido, sugere-se que a superexpressão de BCL-2 nos tumores astrocíticos possa ser indicativa de fenótipos mais agressivos, configurando ainda um potencial alvo terapêutico |
| Disciplines: | Medicina |
| Keyword: | Neurología, Oncología, Inmunología, Inmunohistoquímica, Astrocitoma, Apoptosis, BCL-2, BAX |
| Keyword: | Medicine, Neurology, Oncology, Immunohistochemistry, Astrocytoma, Apoptosis, BCL-2, BAX, Immunology |
| Full text: | Texto completo (Ver HTML) |
