Background: INI-1, located on chromosome 22q11.2, is a member of the SWI/SWF chromatin remodeling complex and is expressed in all normal tissues. INI-1 encodes a protein of HSWI/SNF chromatin remodeling complex with unknown function, which is prone to mutation and deletion in malignant rhabdoid tumors (MRT). "In most malignant rhabdoid tumors (including atypical teratoma/rhabdoid tumor of the central nervous system in children) and epithelioid sarcomas, INI-1 is inactivated, and the majority of medulloblastomas and primitive neuroectodermal tumors express INI-1."