ROR1 and osteosarcoma: Studies have shown that ROR1 is expressed on CSCs in chronic lymphocytic leukemia, mantle cell lymphoma, glioblastoma, neuroblastoma, osteosarcoma, pancreatic, gastric, fallopian, endometrial, ovarian, and breast cancer, and its inhibition can affect the maintenance of these cells [6,9,10,11,12,13,14,15,16,17,18].