Novel Two MRT Cell Lines Established from Multiple Sites of a Synchronous MRT Patient.

Malignant rhabdoid tumor (MRT) is a rare, aggressive neoplasm found in young children, caused by inactivation of a single gene, SNF5 (INI1, SMARCB1). MRT cases with multifocal tumors at diagnosis are categorized as synchronous MRT, often with a germline mutation of SNF5. The aim of this study was to establish new models useful in clarifying the biological basis of synchronous MRT. We established two novel MRT cell lines, designated as KP-MRT-KS and KP-MRT-KSa, derived from different lesions and at a different time from a synchronous multifocal 7-month-old female MRT patient. Both cells showed typical morphology of MRT, with a compound genomic mutation in exons 2 and 5 of the SNF5 gene. The exon 2 mutation was found in the germline. These cell lines could serve as powerful tools for unveiling the molecular mechanism of refractory synchronous MRT.