3D Spheroid Invasion Assay for High-Throughput Screening of Small-Molecule Libraries.

Cancer metastasis is a complex cascade that involves the activation of cancer cell migration and invasion of the extracellular space. Cancer-associated fibroblasts (CAFs) are known inducers of cancer cell invasion. However, current in vitro invasion assays such as the Boyden chamber assay are cumbersome and low throughput. Therefore, there is an urgent need for new ex vivo, surrogate invasion assays that can faithfully recapitulate the cancer cell invasion process in vitro and are amenable to large-scale screening of small-molecule libraries in a high-throughput fashion. Here, we describe a well-established high-throughput three-dimensional (3D) spheroid invasion assay as a powerful tool to identify novel molecular targets that can potentially mediate CAF-dependent cancer cell invasion.