ARF6 and cancer: Both CLIC4 and Arf6 play regulatory roles in pathways enhancing cell proliferation, migration, increase endothelial permeability, angiogenesis, and are predictors of poor prognosis in cancer.5,41–43 Accordingly, Arf6 siRNA and SecinH3 inhibited CLIC4-induced HIF activation and angiogenic responses in cultured HPAECs.