Many of these client proteins probably bind to Exportin 1 via various adapter molecules, and they include tumor suppressors (e.g., p53, p27), many oncogene proteins (e.g., cyclins) and important regulators of fundamental cellular processes, including intracellular vesicle formation, cytoskeleton functions, ribosome maturation and translation, and mRNA degradation [7,18,19]. The gene discussed is XPO1; the disease is neoplasm.