Myogenin--a more specific target for RT-PCR detection of rhabdomyosarcoma than MyoD1.
BACKGROUND
MyoD1 and myogenin are differentially expressed in early myogenesis and have been identified in rhabdomyosarcoma (RMS). This study evaluates reverse transcriptase-polymerase chain reaction (RT-PCR) for MyoD1 and myogenin mRNA as diagnostic markers of RMS, and the potential application of this method for the detection of small volume disease in bone marrow (BM) and peripheral blood (PB).


METHODS
Expression of MyoD1 and myogenin mRNA was examined by RT-PCR in RMSs (9 alveolar RMS, 10 embryonal RMS, 1 pleomorphic RMS), and 21 other paediatric tumor samples (10 neuroblastoma, 10 Ewing sarcomas, and 1 Sarcoma (not otherwise specified) (S(NOS)). BM (n = 19) and PB (n = 22) samples from the same RMS study population were also examined for MyoD1 and myogenin mRNA expression.


RESULTS
Positive expression of both markers was demonstrated in adult muscle, but not in normal PB. Myogenin mRNA was expressed in 16/18 and MyoD1 mRNA in 12/12 RMSs studied. Myogenin was not expressed in 10/10 neuroblastomas, but was present in 2/10 Ewing sarcomas. However, MyoD1 mRNA was detected in 10/10 Ewing sarcomas and 7/10 neuroblastomas. Myogenin mRNA was detected in two BM samples from children with histologically negative BM and in 1/22 PB samples. Detection of MyoD1 mRNA in BM and PB was compromised by the amplification of a similar sized, non-specific product.


CONCLUSIONS
Myogenin mRNA is a more specific marker than MyoD1 for the diagnosis of RMS. Myogenin mRNA is potentially a useful target for the assessment of small volume disease in RMS.
Michelagnoli
Maria P
MP
Candlelighter's Children's Cancer Research Laboratory, St. James's University Hospital, Leeds, United Kingdom. maria.michelagnoli@uclh.org
Burchill
Susan A
SA
Cullinane
Catherine
C
Selby
Peter J
PJ
Lewis
Ian J
IJ
D000293:Adolescent; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000235:genetics; D019046:Bone Marrow Neoplasms / Q000737:chemistry / Q000175:diagnosis; D002648:Child; D002675:Child, Preschool; D005069:Evaluation Studies as Topic; D015972:Gene Expression Regulation, Neoplastic; D019337:Hematologic Neoplasms / Q000737:chemistry / Q000175:diagnosis; D006801:Humans; D007223:Infant; D024510:Muscle Development; D017570:MyoD Protein / Q000032:analysis* / Q000235:genetics; D018008:Myogenin / Q000032:analysis* / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D012334:RNA, Neoplasm / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012208:Rhabdomyosarcoma / Q000737:chemistry* / Q000175:diagnosis*; D012680:Sensitivity and Specificity
D014408:Biomarkers, Tumor; C503799:MYOG protein, human; D017570:MyoD Protein; D018008:Myogenin; D012333:RNA, Messenger; D012334:RNA, Neoplasm