XPO1 overexpression in cancer cells can lead to the mislocalization of multiple tumor-suppressing proteins (TSPs) including p21, p53, p73, p27, Forkhead box O (FOXO), Retinoblastoma (Rb)1, Adenomatous polyposis coli (APC), Breakpoint Cluster Region-Abelson (BCR-ABL), Inhibitor of kappa B (IκB), and Protein Phosphatase (PP)2A, and contribute to oncogenesis and cancer progression [7,11,12]. This evidence concerns the gene RB1 and cancer.