Table 2.

Advantages and disadvantages of transwell-based tumor models.

Transwell model	Description	Advantages	Disadvantages
Migration	Cancer cells pass through transwell membrane, analogous to leaky endothelium	• Easily implemented, low-cost assay • High throughput • Can be used to compare metastatic potential of cells	• Low physiological relevance • Can only assay single-cell motility • Migration and invasion assays can result in conflicting data
Invasion	Cancer cells pass through a layer of ECM and the transwell membrane
Transendothelial migration	Cancer cells pass through a monolayer of endothelial cells to assay extravasation