The loss of INI1 protein activity was first demonstrated in aggressive pediatric tumors, including atypical teratoid/rhabdoid (AT/RT) tumor of the central nervous system and malignant rhabdoid tumor of the kidney.
CNS and extra-CNS tumors had an identical SMARCB1 amplification (n = 1) or very similar DNA methylation pattern (n = 1) suggestive of clonal origin.All patients died of tumor progression.
Cribriform neuroepithelial tumor (CRINET) is a recently recognized central nervous system neoplasm that arises in the ventricles of young children and is characterized by primitive, non-rhabdoid SMARCB1-deficient cells with prominent cribriform architecture.
We and other investigators have identified deletions and mutations of the INI1 gene in the majority of rhabdoid tumors of the central nervous system, kidney, and extrarenal tissues.