1.
Domanski, Henryk, et al.
(författare)
Cytologic features of primary, recurrent, and metastatic dermatofibrosarcoma protuberans
2002
Ingår i: Cancer. - : Wiley. - 1097-0142 .- 0008-543X. ; 96:6, s. 351-361
Tidskriftsartikel (refereegranskat) abstract
BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a low-grade spindle cell neoplasm involving both dermis and subcutis. Its diagnosis may be difficult to render from cytologic smears, as it shares some features with other spindle cell lesions occurring in the skin and soft tissue.METHODS: Fourteen aspiration smears from 12 patients with primary, recurrent, or metastatic DFSP, examined by fine-needle aspiration biopsy (FNAB), were reviewed and compared with corresponding surgical specimens (13 aspirates) and clinical data (one aspirate). The cytologic features of DFSP were evaluated. Other spindle cell lesions in the differential diagnoses were discussed.RESULTS: Unequivocal spindle cell sarcoma diagnoses were rendered in nine aspirates, six of which were labeled correctly as DFSP in the original reports. In three aspirates, the preoperative diagnoses were inconclusive with regard to whether the tumors were benign or malignant. Two aspirates were diagnosed erroneously as benign spindle cell lesions. Cytologic features included tight clusters of bland spindle cells embedded in a collagenous/fibrillar and, often, metachromatic matrix along with dissociated, uniform, or slightly atypical spindle cells or bare nuclei. Tissue fragments showing a storiform pattern and entrapped fat tissue, reported in previous series, were less characteristic, presenting in nine and seven aspirates, respectively.CONCLUSIONS: Correct subtyping of DFSP in fine-needle aspiration smears can be difficult, due to its morphologic overlapping with other spindle cell lesions. A combination of cytology with ancillary studies and appropriate clinical information is crucial to establishing a correct diagnosis.
2.
3.
Gisselsson Nord, David, et al.
(författare)
Differentially amplified chromosome 12 sequences in low- and high-grade osteosarcoma.
2002
Ingår i: Genes, Chromosomes and Cancer. - : Wiley. - 1045-2257. ; 33:2, s. 133-140
Tidskriftsartikel (refereegranskat) abstract
Most osteosarcomas are highly aggressive malignancies characterized by a complex pattern of chromosome abnormalities. However, a subgroup of low-grade, parosteal tumors exhibits a relatively simple aberration pattern dominated by ring chromosomes carrying amplified material from chromosome 12. To assess whether sequences from this chromosome were differentially amplified in low- and high-grade osteosarcomas, copy numbers of the CCND2, ETV6, KRAS2, and D12S85 regions in 12p and the MDM2 region in 12q were evaluated by interphase or metaphase fluorescence in situ hybridization (FISH) in 24 osteosarcomas. Amplification of MDM2 was detected in all five low-grade and four high-grade osteosarcomas, all of which showed ring chromosomes. An overrepresentation of 12p sequences was found in 1/5 low-grade and in 9/19 high-grade tumors. Multicolor single-copy FISH analysis of metaphase cells from six high-grade tumors showed that extra 12p material either occurred together with MDM2 in ring chromosomes or was scattered over the genome as a result of complex structural rearrangements. Most tumors (8/10) not containing amplification of the assessed chromosome 12 loci exhibited a nondiploid pattern at evaluation with probes for centromeric alpha satellite sequences. These findings indicate that gain of sequences from the short arm of chromosome 12 could be a possible genetic pathway in the development of aggressive osteosarcoma.
4.
Panagopoulos, Ioannis, et al.
(författare)
Molecular genetic characterization of the EWS/ATF1 fusion gene in clear cell sarcoma of tendons and aponeuroses.
2002
Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136. ; 99:4, s. 560-567
Tidskriftsartikel (refereegranskat) abstract
Clear cell sarcoma (CCS) is a rare malignant soft tissue tumor particularly associated with tendons and aponeuroses. The cytogenetic hallmark is the translocation t(12;22)(q13;q12) resulting in a chimeric EWS/ATF1 gene in which the 3'-terminal part of EWS at 22q is replaced by the 3'-terminal part of ATF1 at 12q. To date, only 13 cases of CCS have been analyzed for fusion genes at the transcription level, and there is no information about the breakpoints at the genomic level. In the present study, we describe the molecular genetic characteristics of CCS from 10 patients. Karyotypes were obtained from 10 cases, 7 of which showed the characteristic t(12;22). As an initial step in the characterization of the EWS/ATF1 and ATF1/EWS chimeras, we constructed an exon/intron map of the ATF1 gene. The entire ATF1 gene spanned >40 kb and was composed of 7 exons. Intron 3, in which most of the genomic breakpoints occurred, was to a large extent (83%) composed of repetitive elements. RT-PCR amplified EWS/ATF1 cDNA fragments in all patients and ATF1/EWS cDNA fragments in 6 of 10 patients. Four types of EWS/ATF1 chimeric transcript, designated types 1-4, were identified. The most frequent chimeric transcript (type 1) was an in-frame fusion of exon 8 of EWS with exon 4 of ATF1. This was the only chimeric transcript in 5 patients but found together with other variants in 3 tumors. The type 2 transcript of EWS/ATF1, an in-frame fusion of exon 7 of EWS with exon 5 of ATF1, was detected in 4 patients, as the only transcript in 1 case and together with other variants in 3 cases. An in-frame fusion of exon 10 of EWS with exon 5 of ATF1 (type 3) was found in 1 patient as the only transcript, and an out-of-frame fusion of EWS exon 7 with ATF1 exon 7 (type 4) was detected in 1 patient together with type 1 and type 2 transcripts. Sequencing of the amplified ATF1/EWS cDNA fragments showed in 5 patients that ATF1 exon 3 was fused with EWS exon 10, resulting in an out-of-frame chimeric transcript. In 1 case, nt 428 of ATF1 (exon 4) was fused with EWS exon 8; at the junction, there was an insertion of 4 nucleotides, also resulting in an out-of-frame transcript. Genomic extra long PCR and sequence analysis mapped the genomic breakpoints to introns 7, 8 and 9 of EWS and intron 3 and exon 4 of ATF1. While a simple end-to-end fusion was observed in 2 cases, additional nucleotides were found at the junctions in 2 other cases. In addition, topoisomerase I consensus sequences were found close to the junctions, suggesting that this enzyme may participate in the genesis of the EWS/ATF1 fusion.
5.
Panagopoulos, Ioannis, et al.
(författare)
Molecular genetic characterization of the EWS/CHN and RBP56/CHN fusion genes in extraskeletal myxoid chondrosarcoma.
2002
Ingår i: Genes, Chromosomes and Cancer. - : Wiley. - 1045-2257. ; 35:4, s. 340-352
Tidskriftsartikel (refereegranskat) abstract
Extraskeletal myxoid chondrosarcoma (EMC) is a soft-tissue neoplasm cytogenetically characterized by the translocations t(9;22)(q22;q11-12) or t(9;17)(q22;q11), generating EWS/CHN or RBP56/CHN fusion genes, respectively. In the present study, 18 EMCs were studied both cytogenetically and at the molecular level. Chromosomal aberrations were detected in 16 samples: 13 with involvement of 9q22 and 22q11-12, and three with rearrangements of 9q22 and 17q11. Fifteen cases had an EWS/CHN fusion transcript and three had an RBP56/CHN transcript. The most frequent EWS/CHN transcript (type 1; 10 tumors), involved fusion of EWS exon 12 with CHN exon 3, and the second most common (type 5; two cases) was fusion of EWS exon 13 with CHN exon 3. In all tumors with RBP56/CHN fusion, exon 6 of RBP56 was fused to exon 3 of CHN. By genomic XL PCR and sequence analyses, the breakpoints from 14 cases were mapped in the EWS, RBP56, and CHN genes. In CHN, 12 breakpoints were found in intron 2 and only two in intron 1. In EWS, the breaks occurred in introns 7 (one break), 12 (eight breaks), and 13 (one break), and in RBP56 in intron 6. Repetitive elements such as Alu and LINE sequences seem to have limited, if any, importance in the genesis of EWS/CHN and RBP56/CHN chimeras. Furthermore, there were no chi, chi-like, topoisomerase II, or translin consensus sequences in the introns harboring the translocation breakpoints, nor could the number of topo I sites in EWS, RBP56, and CHN introns explain the uneven distribution of the breakpoints among EWS or CHN introns. Additional genetic events, such as nucleotide insertions, homologies at the junction, deletions, duplications, and inversions, were found to accompany the translocations, indicating that the chromosomal translocations do not require sequence-specific recombinases or extensive homology between the recombined sequences. Copyright 2002 Wiley-Liss, Inc.
