Caracterização de linhagens derivadas de câncer de mama humano e avaliação do efeito induzido pelo paclitaxel sobre a susceptibilidade de células de câncer de mama à radiação gama

• Ano de defesa: 2009
• Autor(a) principal: Cristiane Rodrigues Correa
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: câncer de mama; Bioquímica; Raios gama; Mamas Câncer; Linhagem (Genética)
• Link de acesso: http://hdl.handle.net/1843/CMFC-7X4JBZ

Breast cancer is the sixth leading cause of cancer death in the world, and the most frequent type in women. Each year, over 22% of the new cases of cancer in women are breast cancer. Advances in breast cancer detection and treatment have contributed to improve the rate of survival, although mortality rates remain significantly high. Despite all these advances, more efficient diagnostic methods and effective treatments are necessary. The establishment of breast cancer cell lines is an important tool to understand biological processes involved in this disease, as well as the development of potential model of treatment. In the present work, two cell lines, MACL-1 and MGSO-3, from human primary breast cancer were characterized and the effect of paclitaxel on the radiation response of breast cancer cell line was investigated. Characterization of the cell lines included morphological examination that demonstrated a typical epithelial morphology and PCR analyses which showed that both cell lines were telomerase positive. Real time PCR showed that the levels of MUC1 expression in both cell lines were greater than in MDA-MB-231 cell line. Moreover, MACL-1 and MGSO-3 were capable of growing in soft agar culture, which suggests their metastatic potential, and both demonstrated a positive tumorogenic potential in nude mice. These experimental models open new perspectives on the investigation of breast cancer biology and treatment. Our data also showed that pretreatment with paclitaxel enhanced radiation-mediated cell death, promoting caspase-3 activity and apoptosis in breast cancer cell lines. Although, only MACL-1 showed significant difference in clonogenic assays between radiosensivity parameters calculated from irradiated cells, with or without paclitaxel. In conclusion, the results obtained showed that paclitaxel did not induce systematically a radiosensitization and that a synergistic effect was observed in MACL-1 cell line.