XIST and Alzheimer disease: Recently, Zhang et al. carried out a study in order to prove lncRNA XIST’s effect on AD pathogenic mechanism and identify its corresponding pathway, with the findings showing that lncRNA XIST regulated smooth muscle cell proliferation and apoptosis through the sponge of miR-17 and the regulation of the subsequent downstream PTEN to affect the development of aortic dissection in mice [15].