XPO1 and osteosarcoma: Among the various targets involved in nucleo-cytoplasmic transport, the nuclear export receptor XPO1 (exportin 1, CRM1) represents the most advanced therapeutic target for cancer therapy due to its hyperactivity in various malignant tumors, such as ovarian cancer, glioma, and osteosarcoma, as well as pancreatic cancer and cervical cancer [19,23,24].