Isolamento e caracterização de células-tronco/progenitoras a partir de cultivo in vitro de linhagens celulares de carcinoma de mama humana

• Ano de defesa: 2013
• Autor(a) principal: Milene Pereira Moreira
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Mamoesferas; Linhagem celular; Câncer de mama; Cultura tridimensional; Células-tronco do câncer; Células-tronco; Neoplasias da mama; Imagem tridimensional; Células-tronco neoplásicas; Células Cultura e meios de cultura; Linhagem celular tumoral; Mama Câncer; Expressão gênica
• Link de acesso: http://hdl.handle.net/1843/BUOS-97YG7V

Breast cancer is the second most common type of cancer worldwide and the most common among women. It is a heterogeneous disease, possibly due to the existence of a small population of cells in these tumors with stem cell properties, known as cancer stem cells (CSCs). The CSCs hypothesis proposes a hierarchical organization of cells within the tumor where only the CSCs has the ability of sustain tumor growth, resistance to conventional therapies and disease recurrence.Cells with function characteristic of progenitor/stem cell can be prospectively isolated and propagated in vitro as non-adherent spheres, termed mammospheres. Therefore, this study aimed to characterize human cell lines of breast carcinoma BT-549 and Hs 578T , mammospheres-derived from the cell lines cultured in vitro in plastic substrate and in three -dimensional system (Matrigel). For this was made characterization by optical microscopy (Phaloidin/DAPI, Imageit, -tubulin, E-cadherin and VE-caherin) and by flow cytometry (CD90, CD146, CD105, CD31, CD34, CD45 e CD24) and, analysis of expression profile by qRT -PCR of the genes ERBB2, KRT5, MKI67, CDH3 e TP63. The results obtained showed that both cell lines cultured in 2D and in 3D, express -tubulin, with the exception of Hs 578T cell line cultured in 3D, and do not express E -cadherin and VE-cadherin. The immunophenotype classified the BT-549 cell line as CD90+/CD146+/CD105+/CD31-/CD34-/CD45-/CD24+ and the Hs 578T cell line as CD90+/CD146+/CD105+ /CD31-/CD34-/CD45-/CD24-. Both cell lines cultured in Matrigel can form three-dimensional structures and presented a differentiated expression of the genes analyzed when compared with the cell lines cultured in 2D. Under undifferentiating condition s these cell lines form mammospheres-derived, being that the cell line BT -549 demonstrated a better result. The mammospheres-derived and the mammosphere cultured in 3D showed expression of -tubulin and no expression of E-cadherin and VE-cadherin. The gene expression analysis showed that the mammosphere-derived presented a differentiated expression of the genes studied when compared with the parental cell lines, suggesting cues of the participation of these genes in the formation of mammospheres. In 3D culture the mammospheres seems undergoes differentiation and presented a differentiated expression of the genes analyzed compared with the mammosphere - derived from the cell lines. Based in our results, the cell line BT-549 look like a good model to study in vitro the CSCs, being the genes ERBB2 and TP63 potential markers of CSCs.