Whole-genome profiling of chromosomal aberrations in hepatoblastoma using high-density single-nucleotide polymorphism genotyping microarrays.
To identify the genomic profile and elucidate the pathogenesis of hepatoblastoma (HBL), the most common pediatric hepatic tumor, we performed high-density genome-wide single-nucleotide polymorphism (SNP) microarray analyses of 17 HBL samples. The copy number analyzer for GeneChip(R) (CNAG) and allele-specific copy number analysis using anonymous references (AsCNAR) algorithms enabled simple but sensitive inference of allelic composition without using paired normal DNA. Chromosomal aberrations were observed in 15 cases (88%). Gains in chromosomes 1q, 2 (or 2q), 8, 17q, and 20 and losses in chromosomes 4q and 11q were frequently identified. High-grade amplifications were detected at 7q34, 14q11.2, and 11q22.2. Several types of deletions, except homozygous deletion, were identified. Most importantly, copy-neutral loss of heterozygosity (uniparental disomy [UPD]) at 11p15 was detected in four of the 17 HBL samples. Insulin-like growth factor II (IGF2) and H19 genes were located within this region. The methylated status of this region indicated the paternal origin of the UPD. The expression patterns of IGF2 and H19 were opposite between genes with and without the UPD. This difference in the expression patterns might influence the clinical features of HBL.
Suzuki
Makoto
M
Department of General Surgical Science, Graduate School of Medicine, Gunma University Graduate School, 3-39-15 Showa, Maebashi, Gunma, Japan.
Kato
Motohiro
M
Yuyan
Chen
C
Takita
Junko
J
Sanada
Masashi
M
Nannya
Yasuhito
Y
Yamamoto
Go
G
Takahashi
Atsushi
A
Ikeda
Hitoshi
H
Kuwano
Hiroyuki
H
Ogawa
Seishi
S
Hayashi
Yasuhide
Y
D000483:Alleles; D045744:Cell Line, Tumor; D002869:Chromosome Aberrations; D002877:Chromosomes, Human; D020869:Gene Expression Profiling; D015894:Genome, Human; D023281:Genomics; D005838:Genotype; D018197:Hepatoblastoma / Q000235:genetics*; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis; D020641:Polymorphism, Single Nucleotide