Abstract A40: Development of a perfusion-based 3D human tri-culture breast microtumor

Background: The tumor microenvironment (TME) is a 3D, dynamic interaction between tumor and stromal cells, extracellular matrix, and soluble factors which can promote tumor progression and resistance to therapy. Significant efforts are being made to develop long-term in vitro TME models to study cancer biology, improve drug development, and guide clinical decisions. We have developed a cost-effective micro-bioreactor culture device which enables a wide variety of dynamic cellular and TME interactions that can be monitored with in situ, label free, and non-lytic microscopic analysis. Using the 3DKUBE™, we developed a 3D breast cancer model composed of MCF-7 cells and fibroblasts in segregated co-culture and identified a highly active PI3K inhibitor that had limited activity in 2D monoculture. Based on a more complex morphologic and functional 3D mammary gland model that incorporates multiple human primary cells including epithelial cells (HuMEC), mammary fibroblasts, and adipocytes, our long-term 3D perfused tri-culture breast cancer model is designed to evaluate drug response continuously using non-lytic analysis. We theorize that different breast cancer epithelial cells will be supported in a standard 3D stromal platform which supports mammary gland function. Herein, we describe the 3DKUBE™ modifications and early optimization of a defined stromal TME which supports HuMECs in 3D perfusion. Materials & Methods: Primary human cells were used to optimize seeding conditions for silk fibroin scaffolds containing Matrigel™/collagen hydrogels, including, media composition, cellular ratios, flow rates, and analytical methods for the 3DKUBE™. Destructive analytical methods included morphology (HE 2014 Feb 26-Mar 1; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2015;75(1 Suppl):Abstract nr A40. doi:10.1158/1538-7445.CHTME14-A40