Investigation of PAX3/7-FKHR fusion genes and IGF2 gene expression in rhabdomyosarcoma tumors.
The purpose of our study was to investigate the prevalence of the PAX3/7-FKHR fusion genes and quantify the IGF2 gene expression in rhabdomyosarcoma (RMS) samples. Soft tissue sarcomas account 5% of childhood cancers and 50% of them are RMS. Morphological evaluation of pediatric RMS has defined two histological subtypes, embryonal (ERMS) and alveolar (ARMS). Chromosomal analyses have demonstrated two translocations associated with ARMS, resulting in the PAX3/7-FKHR rearrangements. Reverse transcriptase-polymerase chain reaction (RT-PCR) is extremely useful in the diagnosis of ARMS positive for these rearrangements. Additionally, several studies have shown a significant involvement of IGF pathway in the pathogenesis of RMS. The presence of PAX3/7-FKHR gene fusions was studied in 25 RMS samples from patients attending the IOP-GRAACC/UNIFESP and three RMS cell lines by RT-PCR. IGF2 gene expression was quantified by qPCR and related with clinic pathological parameters. Of the 25 samples, nine (36%) were ARMS and 16 (64%) were ERMS. PAX3/7-FKHR gene fusions expression was detected in 56% of ARMS tumor samples. IGF2 overexpression was observed in 80% of samples and could indicate an important role of this pathway in RMS biology.
Pediatric Oncology Institute (GRAACC), Department of Pediatrics, Federal University of São Paulo, São Paulo, SP, Brazil. rramos.souza@hotmail.com
Robson Ramos
RR
de Souza
Indhira Dias
ID
Oliveira
Eliana Maria Monteiro
EM
Caran
Maria Teresa de Seixas
MT
Alves
Simone
S
Abib
Silvia Regina Caminada
SR
Toledo
D002282:Adenocarcinoma, Bronchiolo-Alveolar / Q000235:genetics / Q000378:metabolism; D000293:Adolescent; D045744:Cell Line, Tumor; D002648:Child; D005260:Female; D000071161:Forkhead Box Protein O1; D051858:Forkhead Transcription Factors / Q000235:genetics* / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007335:Insulin-Like Growth Factor II / Q000235:genetics* / Q000378:metabolism; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism; D008297:Male; D015514:Oncogene Proteins, Fusion; D000072041:PAX3 Transcription Factor; D051763:PAX7 Transcription Factor / Q000235:genetics* / Q000378:metabolism; D051761:Paired Box Transcription Factors / Q000235:genetics* / Q000378:metabolism; D012189:Retrospective Studies; D012208:Rhabdomyosarcoma / Q000235:genetics* / Q000378:metabolism; D018233:Rhabdomyosarcoma, Embryonal / Q000235:genetics / Q000378:metabolism
C085126:FOXO1 protein, human; D000071161:Forkhead Box Protein O1; D051858:Forkhead Transcription Factors; C035170:IGF2 protein, human; D015514:Oncogene Proteins, Fusion; D000072041:PAX3 Transcription Factor; C489409:PAX3 protein, human; D051763:PAX7 Transcription Factor; C497321:PAX7 protein, human; D051761:Paired Box Transcription Factors; D007335:Insulin-Like Growth Factor II