In contrast, after subsequent dissection of lung sections and hematoxylin and eosin staining (H&E staining), we observed a greater number of metastatic tumors and larger tumor volumes in the lungs of mice continually exposed to induced HOTAIR (iHOT+ mice + Dox treatment, Figure 2D–E, Figure 3—figure supplement 1A), indicating that HOTAIR overexpression drives metastatic progression. The gene discussed is HOTAIR; the disease is neoplasm.