XIST and thyroid cancer: LncRNAs, such as MALAT1, HOTAIR, TUG1, XIST and so on, could promote cancer cell proliferation, invasion and/or migration, including multiple myeloma [6], triple-negative breast cancer [7], cervical cancer [8, 9], pancreatic cancer [10], bladder cancer [11], as well as thyroid cancer [12–15].