Fig. 2.

Overview of in vitro models for studying breast cancer physiopathology and for drug screening applications. The 2D tumor model is typically represented by a monolayer culture of cells; 3D tumor models (e.g., spheroids, cancer cells encapsulated within scaffolds/hydrogels, microcarriers, and others) can reproduce native cell-cell communication and cell-ECM interactions. Ex vivo (tumor biopsy) and in vivo models can be used for drug screening, drug discovery and development, biomarkers detection and to indentify molecular pathways involved in breast tumor. Microfluidic chip models can mimic the in vivo physiopathology of breast cancer, such as vasculature growth, gradient generation, interstitial flow, or shear stress. In addition, important events of the metastatic cascade can be easily reproduced and studied, such as tumor growth, invasion, intravasation, vasculature CTC transit, extravasation, or organ specificity. (Created using Biorender.com).