ARHGAP17 localizes to invadopodia. (A) Representative micrographs of CTRL and ARHGAP17 KO SUM159 cells stained for F-actin and ARHGAP17. Arrowheads highlight invadopodia clusters (scale bar, 10 μm). (B) Representative TIRF micrographs of a SUM159 cell expressing TKS5-mTagBFP2 as a marker for invadopodia and ARHGAP17-GFP (expressed in ARHGAP17 KO cells) forming an invadopodia cluster after 30 min PDBu treatment (scale bar for both panels, 5 μm). (C–E) STORM reconstructions of SUM159 cells treated with PDBu showing myc-ARHGAP17 (expressed in ARHGAP17 KO cells), cortactin, and paxillin localization to invadopodia as defined by F-actin staining (scale bar, 1 μm; inset scale bar, 0.25 μm). The zoomed regions are marked by a dashed line. (F) Quantification of STORM reconstructions using the radial intensity analysis of F-actin, myc-ARHGAP17, cortactin, and paxillin in invadopodia. Lines are expressed as mean ± SEM of three independent experiments in which at least 20 invadopodia per condition per experiment were measured.