OBJECTIVETo detect the PAX3/PAX7-FKHR fusion transcripts to identify genetic alteration in embryonal rhabdomyosarcoma (ERMS) and alveolar rhabdomyosarcoma (ARMS) tissues.

METHODSOne-step reverse transcription- polymerase chain reaction (RT-PCR) were used to detect the expression of the PAX3/PAX7-FKHR fusion transcrips in 16 cases of rhabdomyosarcoma (7 cases of ARMS, 9 cases of ERMS) and 16 specimens were compared to the surrounding normal tissue. Comparative genomic hybridization (CGH) was employed to detect the genomic imbalance (DNA loss or amplification) in 16 RMS cases.

RESULTSPAX3-FKHR fusion transcripts were positive in 3/7 and PAX 7-FKHR fusion transcripts were positive in 2/7 of ARMS patients, respectively, and were all negative in ERMS and Control tumors. There were different chromosome variations for each RMS, chromosome amplification was frequently seen in 1p36 (69%), 5q32 (56%), 8q21 (63%), 13q14 (69%), 19q (63%), 20q (56%). Chromosome loss was frequently seen in 3p21-pter (56%), 9p23-pter (50%), 10q (69%), 16/16q24 (56%).

CONCLUSIONOne-step RT-PCR assay for detection specific fusion gene provides a useful tool for confirmation of the diagnosis of RMS in diagnostically difficult cases and in retrospective studies. Chimeric gene transcript resulting from specific chromosomal translocations is a reliable index for the molecular diagnosis of RMS.

Chromosome Aberrations ; Comparative Genomic Hybridization ; Forkhead Box Protein O1 ; Forkhead Transcription Factors ; genetics ; Gene Expression Regulation, Neoplastic ; Humans ; Oncogene Proteins, Fusion ; genetics ; PAX3 Transcription Factor ; PAX7 Transcription Factor ; genetics ; Paired Box Transcription Factors ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Rhabdomyosarcoma ; genetics

OBJECTIVEThe aim of this study was to characterize the profile of chromosomal imbalances of alveolar rhabdomyosarcoma (ARMS).

METHODSOne-step RT-PCR was used to detect the expression of PAX3-FKHR and PAX7-FKHR fusion transcripts in 10 cases of alveolar rhabdomyosarcoma and in an ARMS cell line. Comparative genomic hybridization (CGH) was used to investigate the genomic imbalances in these cases. It was analyzed according to the histological type, pathologic grading, clinical staging, gender and age, respectively.

RESULTSThe 10 patients with alveolar rhabdomyosarcoma showed evidence of increased or decreased DNA sequence copy numbers involving one or more regions of the genome. (1) The frequently gained chromosome arms of ARMS were 12q, 2p, 6p, 6q, 10q, 2q, 4q, 15q, 1p, 9q, 14q and 18q (> or = 30.0%), and the frequently lost chromosome arms of ARMS were 3p, 6p, 20q and 21q (> 30.0%). (2) The frequently gained chromosome arm translocation associated with ARMS were 12q, 10q, 2p, 2q, 6p, 6q, 1p, 4q, 8q, 11q, 14q and 15q (> 30.0%). The frequently lost chromosome arms were 3p, 5q, 6p, 1q, 8p, 11p, 20q and 21q (> 30.0%). (3) There were no correlation between chromosome changes and histological type, pathologic grade, clinical stage, gender and age, respectively.

CONCLUSIONThese observations suggest that: (1) 12q, 2p, 6p, 6q, 10q, 2q, 4q, 15q, 1p, 9q, 14q, 18q gain and 3p, 6p, 20q, 21q loss may correlated with ARMS-related carcinogenesis; (2) 12q gain may be correlated with translocation.

Adolescent ; Adult ; Aged ; Cell Line, Tumor ; Child ; Chromosome Aberrations ; Chromosome Deletion ; Chromosomes, Human, Pair 12 ; genetics ; Chromosomes, Human, Pair 3 ; genetics ; Chromosomes, Human, Pair 5 ; genetics ; Chromosomes, Human, Pair 6 ; genetics ; Comparative Genomic Hybridization ; DNA Copy Number Variations ; Female ; Humans ; Infant ; Male ; Neoplasm Staging ; Oncogene Proteins, Fusion ; metabolism ; PAX7 Transcription Factor ; metabolism ; Rhabdomyosarcoma, Alveolar ; genetics ; metabolism ; pathology ; Young Adult