Abstract 3013: Study of three-dimensional cell culturing influence on DNA methylation profile

Abstract In this study, we purpose the analysis of the DNA methylation profile of four different human breast cell lines, two non transformed and two tumoral, taking into account the influence of the environment in cell culturing. The extracellular matrix was initially thought to serve as nothing more than a physical support for the cells. However, nowadays is very well known that the extracellular matrix is a key component in cell biology, regulating cell biology and tissue homeostasis. This suggests that there is a bidirectional crosstalk between the cells and the surrounding extracellular matrix. Cell culturing is a commonly used technique in all areas of biology research. Usually, adherent cells are spreading in two-dimensional plates where they growth attached to the plastic surface in two directions. Mammary epithelial cells that are cultured on this conventional way fail to form acinar-like structures and loss tissue specific protein expression. Many of the microenvironment influences can be restored in cell culturing models by using three-dimensional cultures in extracellular matrix gels. 3D culturing of epithelial cells can help to reconstruct the acinar morphology seen in vivo and restore some mammary-specific function, like milk proteins production. DNA methylation plays a significant role in the epigenetic regulation of chromatin structure and gene expression. In this work, we tried to analyze the DNA methylation profile of four different human breast cell lines growth in 2 and 3 dimensions to assess the influence of DNA methylation in the two models. HMEC (finite lifespan human mammary epithelial cell line), MCF10A (spontaneously immortalized, but not transform, human breast epithelial cell line), MCF7 (human breast adenocarcinoma cell line, metastasic) and MDA-MB-231 (human breast adenocarcinoma cell line, metastasic) were growth in plates with and without MatrigelTM basement Membrane Matrix Growth Factor Reduced (BD). 3D culturing was done by spreading the cells in the matrix surface and allowing them to form the characteristic acini of the mammary gland. Morphological differences are evident between the 2 and 3D culture models, being much more accurate the 3D model from a phenotypic point of view. DNA mehtylation status was done by illumina's Infinium Microarrays, comparing the methylation profile of each cell line growth in 2 and 3D. We determined in this way which genes are differentially methylated in 2 and 3 dimensions. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3013. doi:10.1158/1538-7445.AM2011-3013