LncRNA XIST was found to exhibit decreased serum levels during the early stages of ischemic stroke patients, and silencing lncRNA XIST significantly decreased the endothelial migration and tube formation, and exacerbated cerebral vascular injury by notably reducing the expressions of krüppel-like factor 4 (KLF4) and tight junction proteins claudin-5 and ZO-1, leading to larger infarction and worse neurological functions in transient ischemic stroke mice [61]. The gene discussed is CLDN5; the disease is ischemic stroke.