To further investigate the presence of invadosomes in hypoxic and fibrotic zones of IPF tissues, we performed immunochemistry staining for the activated form of cortactin (p(Tyr421)) and TKS5, two invadosome markers that have been shown to localize to actin-rich invadopodial structures and to correlate with invadopodia activity [34,35]. Here, CTTN is linked to idiopathic pulmonary fibrosis.