SDC4 and ovarian carcinoma: Arf6 expression was suppressed in A2780 ovarian carcinoma cells and A375-SM malignant melanoma cells, which both use α5β1, αVβ3, and syndecan-4 to engage fibronectin, and in both cell lines Arf6 inhibition blocked recycling of α5β1 but not αVβ3 (Figures S5B, S5C, S5I, and S5J).