XIST and osteosarcoma: By contrast, lncRNA XIST was found markedly increased in osteosarcoma tissues and cell lines as demonstrated by qRT‐PCR,97, 98 and its expression was negatively associated with OS, and positively correlated with clinicopathological features, including larger tumour size, advanced Enneking stage, LNM and distant metastasis in osteosarcoma,99 suggesting XIST may be used as an independent clinical biomarker in osteosarcoma.100, 101, 102