XIST and breast cancer: As a specific expression of lncRNA in female cells, a large number of studies have shown that XIST is closely related to the high incidence of cancer in women, such as breast cancer (Schouten et al., 2016), cervical cancer (Zhu et al., 2018), thyroid cancer (Liu et al., 2018), and ovarian cancer (Zuo et al., 2019).