Development and characterization of a multi-cellular in vitro model for the study of nanoparticle-cell Interface

Abstract

Triple Negative Breast Cancer (TNBC) is distinguished by various characteristics which are associated to its poor prognosis. This type of cancer is aggressive in nature and has no targeted therapies. The tumor microenvironment has shown to modulate tumor cell behavior and response to clinical therapies. Current in vitro technologies allow us to observe multicellular interactions for extended periods; however, these present a variety of limitations including the need for cell sorting, requirement of large amounts of cells, and lack of tunable discrete adjacent compartments. Other technologies such as microfluidic platforms lack a user-friendly interface and require specialized instrumentation and training, making it difficult to be routinely used in a cell biology laboratory. To overcome these problems, an open multi-microwell triculture device was manufactured to probe tumor-stromal interactions. The devices were printed out of polystyrene sheets using a razor-blade plotter and manually layered into a 3-dimensional structure. We have evaluated the effect of normal and cancerous stromal cell clusters (fibroblasts and macrophages) in modulating tumor behavior in MDA-MB-231 cells. Tumor cell proliferation was evaluated at 72hrs cultured with stromal clusters under exposure to stress conditions. Results for normal stromal cell clusters show no significant difference in proliferation at 37°C and 41°C. On the other hand, cancer associated cells show an increased proliferation rate of 11.7% for 37°C than for 41°C. Normal stroma shows potential damping on the effects of the high temperature stress on the cells, as no significant difference was observed. Thus, normal stroma improves recovery from heat damage as compared to cancer-stroma. Multi-adjacent microwell stickers are a fast prototyping culture platform and provide flexibility for testing diverse biomaterials with varying conditions for each cell type in multi-culture cell signaling studies.