Aberrations of the hSNF5/INI1 gene are restricted to malignant rhabdoid tumors or atypical teratoid/rhabdoid tumors in pediatric solid tumors.
The hSNF5/INI1 gene, which encodes a subunit of the SWI/SNF family of chromatin-remodeling complexes and is located at 22q11.2, has been reported as a tumor suppressor gene inactivated in malignant rhabdoid tumors (MRTs). We analyzed this gene in varieties of pediatric solid tumors including MRTs, using the reverse transcription-polymerase chain reaction (PCR) and PCR-single strand conformation polymorphism method. We found 5 homozygous deletions, 2 truncated mutations, one missense mutation, and one silent mutation of the hSNF5/INI1 gene in 7 MRT cell lines, and one homozygous deletion, one microdeletion, one splicing acceptor site mutation, and one absence of expression in 7 fresh tumor tissues of MRT and atypical teratoid (AT)/rhabdoid tumors (RTs). Homozygous deletions were also found in one (KYM-1) of 8 rhabdomyosarcoma (RMS) cell lines. To investigate characteristics of the KYM-1 cell line, we have established KYM-1 tumors in nude mice into which KYM-1 cells were transplanted. Notably, we found that MyoD1, known as a marker for RMS, was not expressed in the KYM-1 cell line as well as MRT cell lines and fresh tumors. Histopathologic, cytogenetic, and molecular studies of the KYM-1 cell line and KYM-1 tumors in nude mice have revealed that this RMS cell line should be MRT rather than RMS. RMS-carrying aberrations of the hSNF5/INI1 gene should be reevaluated. No aberrations of this gene were found in the other 34 cell lines or 80 fresh tumor specimens except the single nucleotide polymorphisms in the 3' noncoding region. These results suggest that alterations of the hSNF5/INI1 gene were restricted to MRTs or AT/RTs in pediatric solid tumors.
Uno
Kaoru
K
Department of Pediatrics, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
Takita
Junko
J
Yokomori
Kinji
K
Tanaka
Yukichi
Y
Ohta
Shigeru
S
Shimada
Hiroyuki
H
Gilles
Floyd H
FH
Sugita
Kanji
K
Abe
Satoshi
S
Sako
Masahiro
M
Hashizume
Kohei
K
Hayashi
Yasuhide
Y
D000328:Adult; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D002648:Child; D002675:Child, Preschool; D002868:Chromosomal Proteins, Non-Histone; D020732:Cytogenetic Analysis; D004268:DNA-Binding Proteins / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D051379:Mice; D008819:Mice, Nude; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018335:Rhabdoid Tumor / Q000235:genetics* / Q000473:pathology; D000071796:SMARCB1 Protein; D017422:Sequence Analysis, DNA; D013724:Teratoma / Q000235:genetics* / Q000473:pathology; D014157:Transcription Factors; D014407:Tumor Cells, Cultured
D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D000071796:SMARCB1 Protein; C513266:SMARCB1 protein, human; C513265:Smarcb1 protein, mouse; D014157:Transcription Factors