Invadopodia

Invadopodia are actin-rich protrusions of the plasma membrane that are associated with degradation of the extracellular matrix in cancer invasiveness and metastasis. 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. Invadopodia can be visualized by the holes they would create in fibronectin-coated plates or by using immunohistochemistry, as co-localizing puncta of actin with Tks5. Invadopodia can also be used as a marker to quantify the invasiveness of cancer cell lines in vitro using a hyaluronic acid hydrogel assay.