Modeling Breast Acini in Tissue Culture for Detection of Malignant Phenotype Reversion to Non-Malignant Phenotype

Backgrounds: Evidence is accumulating to support disruption of tissue architecture as a powerful event in tumor formation. For the past four decades, intensive cancer research with the premise of “cancer as a cell based-disease” focused on finding oncogenes or tumor suppressor genes. However, the role of the tissue architecture was neglected. Three dimensional (3D) cell cultures which can recapitulate major aspects of the microenvironment are appropriate models for exploring cancer. For the first time in Iran, we have launched Matrigel based non-malignant, tumorigenic and reverted breast 3D cell cultures. Methods: Non-tumorigenic MCF-10A and tumorigenic MCF-7 breast cell lines were cultured on plastic and Matrigel. MCF-7 cell lines were reverted to normal phenotype via AIIB2 and LY 294002 inhibitors against β1 integrin and class I phosphatidylinositol 3-kinase, respectively. Results: MCF-10A acini were distinguishably different from MCF-7 on Matrigel. MCF-10A formed organized hollow spherical structures which were in stark contrast to the MCF-7 disorganized cluster of cells. Matrigel allowed visual monitoring of MCF-7 cells treated with inhibitors. After treatment of MCF-7 cells, we observed reversion of MCF-7 phenotype toward normal, comparable to MCF-10A acini. Conclusion: The 3D culture provides a microenvironment which allows malignant and non-malignant cells to demonstrate near physiological behavior and this can distinguish nonmalignant from malignant cells. The 3D culture also allows visual monitoring of malignant phenotype reversion to organized spheres. Iran. Biomed. J. 13 (4): 191-198, 2009