ALK and osteosarcoma: It increases miR-384 levels and downregulates the pleiotrophin (PTN) expression, a heparin-binding growth factor involved in cellular differentiation, proliferation, and metastasis, which promotes chemoresistance in osteosarcoma cells by upregulating P-gp via the anti-anaplastic lymphoma kinase (ALK)/ glycogen synthase kinase 3β (GSK3β)/β-catenin signaling pathway.