We found that BMSCs derived exosomes promoted lipid accumulation in osteosarcoma cells, significantly increased triglyceride (TG) and total cholesterol (TC) levels, decreased lipid deposition levels in cells after inhibiting XIST, on this basis, downregulated miR-655 level, the lipid levels, TG and TC contents were also restored, Inhibit the expression of ACLY, the level of TG and TC decreased accordingly (Fig. 7A–D). The gene discussed is ACLY; the disease is osteosarcoma.