XPO1 inhibition prevents export of tumor-suppressor genes from the nucleus. (A) XPO1 mediates leucine-rich NES transport of tumor-suppressor proteins such as TP53 from the nucleus to the cytoplasm. This enhances leukemia cell survival. (B) Selinexor inhibits XPO1 function, leading to nuclear accumulation of TSPs, such as TP53, that can induce leukemia cell death.