(71d) Patterned Co-Culture of Breast Cancer Cells and Stromal Cells As an in Vitro Breast Cancer Model

The process by which normal cells transformed to malignant cells and malignant cells turn into metastatic may depend on the interaction between the cells and the cell microenvironment. Several cancer studies mainly focused on the mutated and highly proliferated cancer cell, however, during the last decade the role of tumor microenvironment has been shown to be very significant in the malignant evolution of neoplasia and cancer progression. Despite the importance of tumor microenvironment, the current scientific understanding remains limited on the interaction between the tumor cells and the surrounding cells. In the present study we investigated the effect of interaction of breast cancer cells and stromal cells on regulation of human epidermal growth factor receptor-2 (HER-2). We developed a patterned co-culture system of breast cancer cells and stromal cells using microfabrication and micropatterning techniques and compared the results with random co-culture and monocultures. We characterized the cellular interaction of breast cancer cells and stromal cells in patterned co-culture by evaluating the morphology, proliferation and expression of HER-2. Both cells were pre-stained with different fluorescent dyes to observe the distinct patterns of each type of cells in co-cultures. Our results indicate two different stages of cancer development. Co-cultures may be an indication of the situation in which breast cancer cells are in paracrine regulation of stromal cells and monocultures may be representative of the situation in which breast cancer cells escaped from paracrine regulation of stromal cells.