[Detection of FUS-CHOP fusion gene in paraffin-embedded tissues and its clinicopathologic significance for myxoid/round cell liposarcomas].
OBJECTIVE
To explore the feasibility of detecting FUS-CHOP fusion gene in formalin-fixed, paraffin-embedded tissue and its application in the diagnosis and differential diagnosis of myxoid/round cell liposarcomas (MRCLs).


METHODS
Forty-four formalin-fixed, paraffin-embedded MRCL samples and 60 control cases (atypical/well-differentiated liposarcoma, pleomorphic liposarcoma, low-grade myofibrosarcoma, etc.) retrieved from the archival files were studied. Nested reverse transcription-polymerase chain reaction (RT-PCR) technique was employed to detect the FUS-CHOP mRNA expression, followed by DNA sequencing confirmation of the PCR product. Housekeeping gene PGK was used to assess the quality of the mRNA templates.


RESULTS
PGK mRNA was detected in 93 of 104 tumor cases (89.4%), including 39 MRCLs cases (39/44, 88.6%) and 90% of the negative control cases. Type II FUS-CHOP fusion transcript was successfully detected in 20 out of 39 (51.3%) MRCL cases. Type I FUS-CHOP fusion transcript was not detected in any MRCLs in this study. All 60 negative control cases were negative for the FUS-CHOP fusion gene transcripts.


CONCLUSIONS
(1) Nested RT-PCR can be used to detect FUS-CHOP mRNA in formalin-fixed, paraffin-embedded tissues. (2) FUS-CHOP is considered a specific molecular and genetic hallmark for MRCLs. Nested RT-PCR is a sensitive and specific technique in detecting FUS-CHOP gene, and can be used in the diagnosis and differential diagnosis of MRCLs.
Xiang
Hua
H
Department of Pathology, Cancer Hospital, Fudan University, Shanghai 200032, China.
Wang
Jian
J
Sun
Meng-hong
MH
Lu
Lei
L
Shui
Ruo-hong
RH
Zhu
Xiong-zeng
XZ
D000293:Adolescent; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008080:Liposarcoma / Q000378:metabolism* / Q000473:pathology; D018208:Liposarcoma, Myxoid / Q000378:metabolism* / Q000473:pathology; D035002:Lower Extremity; D008297:Male; D008875:Middle Aged; D015514:Oncogene Proteins, Fusion / Q000096:biosynthesis* / Q000235:genetics; D016612:Paraffin Embedding; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D034702:RNA-Binding Protein FUS / Q000096:biosynthesis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D012983:Soft Tissue Neoplasms / Q000378:metabolism* / Q000473:pathology; D051742:Transcription Factor CHOP / Q000096:biosynthesis* / Q000235:genetics
D014408:Biomarkers, Tumor; D015514:Oncogene Proteins, Fusion; D012333:RNA, Messenger; D034702:RNA-Binding Protein FUS; C106030:TLS-CHOP fusion protein, human; D051742:Transcription Factor CHOP