Invadopodia are actin-rich protrusions of the plasma membrane that are associated with degradation of the extracellular matrix in cancer invasiveness and metastasis.[1][2] Very similar to podosomes, invadopodia are found in invasive cancer cells and are important for their ability to invade through the extracellular matrix, especially in cancer cell extravasation.[3]
Invadopodia are generally visualized by the holes they create in ECM (fibronectin, collagen etc.)-coated plates, in combination with immunohistochemistry for the invadopodia localizing proteins such as cortactin, actin, Tks5[1][2][4] etc. Invadopodia can also be used as a marker to quantify the invasiveness of cancer cell lines in vitro using a hyaluronic acidhydrogel assay.[5]