Yong et al. [22] proved that miR-613 was significantly downregulated in osteosarcoma patients, and the increased expression of miR-613 directly inhibited the expression of CXCR4, thus reducing the proliferation, migration, and apoptosis of osteosarcoma cells, as well as lung metastasis. The gene discussed is CXCR4; the disease is osteosarcoma.