Siglec-15-induced autophagy promotes migration and invasion by targeting Beclin-1/ATG14 pathways and activating EMT both in vitro and in vivo, and Siglec-15-induced autophagy extends our comprehension of the regulation of autophagy on tumor metastasis and provides a potential target for metastatic osteosarcoma treatment. This evidence concerns the gene BECN1 and osteosarcoma.