XPO5 and neoplasm: In a subset of tumors with microsatellite instability, a genetic defect in XPO5 traps pre‐miRNAs in the nucleus and reduces miRNA processing, whereas reexpression of the wild‐type XPO5 reverses the impaired pre‐miRNA export and the aggressive cellular phenotype, indicating XPO5's tumor‐suppressive property.13