title: Recurrent 12q13-15 chromosomal aberrations, high frequency of isocitrate dehydrogenase 1 mutations, and absence of high mobility group AT-hook 2 expression in periosteal chondromas.
abstract: Periosteal chondroma is a benign cartilage tumor that accounts for <2% of chondromas. In the present study, four cases of periosteal chondromas were cytogenetically investigated and studied for the expression of high-mobility group AT-hook 2 (HMGA2), mutations in codons 132 of isocitrate dehydrogenase (IDH)1 and 172 ofIDH2; mutations -C228T and -C250T in the promoter region of telomerase reverse transcriptase (TERT); and for methylation in the promoter regions ofO-6-methylguanine-DNA methyltransferase (MGMT) and cellular retinol binding protein 1 (CRBP1). Chromosome aberrations of 12q13-15 were found in two out of the four tumors, while two had a normal karyotype. Two periosteal chondromas carried the mutation IDH1R132C (CGT>TGT), and two carried the mutation IDH1R132L (CGT>CTT). However, none of the four tumors had methylatedMGMTandCRBP1promoters or mutations at codon 172 ofIDH2. In addition, -C228T and -C250T mutations were not present in the promoter region ofTERT, nor wasHMGA2demonstrated to be expressed. The present study indicated that in periosteal chondromas, the involvement of 12q13-15 in structural rearrangements may be recurrent but thatHMGA2is not expressed. Additionally, the periosteal chondromas investigated in the study carried a heterozygous IDH1R132 mutation, theMGMTandCRBP1promoters were not methylated, and -C228T and -C250T mutations in the promoter region ofTERTwere absent.
authors.affiliation: Section for Cancer Cytogenetics, Institute for Cancer Genetics and Informatics, The Norwegian Radium Hospital, Oslo University Hospital, Oslo 0424, Norway ; Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo 0316, Norway.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Panagopoulos
authors.affiliation: Section for Cancer Cytogenetics, Institute for Cancer Genetics and Informatics, The Norwegian Radium Hospital, Oslo University Hospital, Oslo 0424, Norway ; Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo 0316, Norway.
authors.forename: Ludmila
authors.initials: L
authors.lastname: Gorunova
authors.affiliation: Department of Radiology and Nuclear Medicine, The Norwegian Radium Hospital, Oslo University Hospital, Oslo 0424, Norway.
authors.forename: Ingeborg
authors.initials: I
authors.lastname: Taksdal
authors.affiliation: Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo 0424, Norway.
authors.forename: Bodil
authors.initials: B
authors.lastname: Bjerkehagen
authors.affiliation: Section for Cancer Cytogenetics, Institute for Cancer Genetics and Informatics, The Norwegian Radium Hospital, Oslo University Hospital, Oslo 0424, Norway ; Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo 0316, Norway ; Faculty of Medicine, University of Oslo, Oslo 0316, Norway.
authors.forename: Sverre
authors.initials: S
authors.lastname: Heim
keywords: 12q13-15 chromosomal aberrations; cytogenetics; high-mobility group AT-hook 2; isocitrate dehydrogenase 1 mutations; periosteal chondromas