DDX3X and medulloblastoma: Among these proteins, the DDX3X helicase has recently been the focus of intensive study as several recent genomic studies have identified recurrent mutations or chromosome translocations within the DDX3X gene in numerous human tumor types, including T-cell acute lymphoblastic leukemia2, 3, chronic lymphoblastic leukemia4, 5, 6, natural killer/T-cell lymphomas7, head and neck squamous cell carcinomas8, lung carcinomas9, carcinomas of the breast corpus and uterine endometrium10, and medulloblastomas (MB)11, 12, 13.