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| Author(s): |
Patricia Bortman Rozenchan
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Faculdade de Medicina (FM/SBD) |
| Defense date: | 2005-04-05 |
| Examining board members: |
Maria Mitzi Brentani;
Patricia Maluf Cury;
Olga Célia Martinez Ibañez;
Luiz Fernando Onuchic;
Ismael Dale Cotrim Guerreiro da Silva
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| Advisor: | Maria Mitzi Brentani |
| Abstract | |
The homeostasis of normal breast depends on interactions between epithelial cells and their associated stroma. Previous studies indicated that in breast cancer carcinoma, tumor associated stromal cells with different functions appear to be emerged. These stromal elements include fibroblasts which modulate tumor behavior providing various growth factors and extracellular matrix components. Our aim was to evaluate the differential gene expression between fibroblasts derived from mammary tissue neoplasic or not and to analyze the influence of normal epithelial cells (MCF10A) on gene expression profile of fibroblasts obtained from neoplasic mammary tissue. Fibroblast primary cultures were established and expression of vimentin and smooth cell actin was positive. Co-culture of these cell types separated by inserts, which allow the passage of soluble factors, was done and total RNA was extracted. After mRNA amplification using a template-switching prime, cDNA probes were synthesized, labeled with fluorochrome conjugated deoxynucleotide, a competitive hybridization was undertaken onto cDNA microarray glass slides in which 4,608 ORESTES (open reading frame expressed sequence tags) from Instituto Ludwig de Pesquisa sobre o Câncer/FAPESP bank were spotted and fluorescent signals were quantified. After normalization, the differentially expressed genes, at a False Discovery Ratio (FDR) less then 0.05, were selected for further analysis. We found 283 differentially expressed genes in fibroblasts obtained from neoplasic mammary tissue when compared with non neoplasic derived fibroblasts. Among these genes, 187 were quantitatively down regulated (fold ranging from 1.05 to 4.14) against 96 up regulated (fold ranging from 1.17 to 7.73). The majority of alterations were related to membrane transport, signaling transduction and biosynthesis. Overall these results could suggest a reduced gene expression along transformation process After coculture with MCF10A cells, we found 566 differentially expressed genes in neoplasic mammary tissue derived fibroblasts, 323 were down regulated (fold ranging from 1.09 to 10.62) and 243 up regulated (fold ranging from 1.03 to 16.62). MCF10A influence in mammary tissue neoplasic derived fibroblasts gene expression could be seen trough the deregulation of expression of some genes possibly related cell proliferation, adhesion, apoptosis and survival. (AU) | |