XIST and neoplasm: XIST has been reported to exert important effects on many tumors including testicular germ cell tumors, ovarian cancer, hematologic cancer and glioblastoma.11, 28, 29, 30 In glioblastoma, XIST could promote tumor cell proliferation and invasion.11 While XIST was reported to be a potent suppressor of hematologic cancer.30 In different tumors, it seems that XIST could have different roles as an oncogene or a tumor suppressor.