FISH analysis revealed COL1A1-PDGFB gene rearrangement in all DFSP cases (n=7), whereas RT-PCR could detect the COL1A1-PDGFB fusion transcript only in 1 DFSP.Two cases were negative.
The COL1A1-PDGFB fusion protein activates the PDGFB receptor and resultant constitutive activation of PDGFR receptor is essential in the pathogenesis of DFSP.
Molecular biology has been valuable in showing dermatofibrosarcoma protuberans and infantile fibrosarcoma that are characterized by COL1A1-PDGFB and ETV6-NTRK3 rearrangements respectively.
A real-time polymerase chain reaction assay for the COL1A1-PDGFB fusion transcript in a series of DFSP containing sarcoma was conducted to determine whether the chimaeric gene could be identified in both components of DFSP-FS and DFSP-PleoSarc.Eight cases were analysed.
Reverse transcription polymerase chain reaction and sequence analysis showed the presence of an identical COL1A1-PDGFB fusion transcript in ordinary DFSP (plaque-like area), FS, and myxoid areas of DFSP.
These results strongly suggest that the COL1A1-PDGFB chimeric gene expression associated with DP, induces tumours formation through production of mature PDGFB, in an autocrine or paracrine way.
With the development of cytogenetic and molecular biology techniques, the detection of fusion transcripts of the collagen type 1a1 (COL1A1) and platelet-derived growth factor-BB (PDGFB) genes has been recognized as a reliable and valuable molecular tool for the diagnosis of DFSPs.
To analyse the presence of collagen type I alpha 1-platelet-derived growth factor beta (COL1A1-PDGFB) transcripts in 20 cases of dermatofibrosarcoma protuberans (DFSP) and to assess the relationship between COL1A1 breakpoints and clinical and histopathological variables.
Genomic gains of COL1A1-PDGFB were found predominantly in the DFSP component of GCF/DFSP hybrids but in none of the pure GCF, suggesting that these gains are associated with the histologic evolution of GCF into DFSP.
This is the first report of a DFSP case where the lack of chromosomes 17 and 22 rearrangement and the absence of COL1A1-PDGFB fusion gene have been demonstrated.
Transforming activity of the chimeric sequence formed by the fusion of collagen gene COL1A1 and the platelet derived growth factor b-chain gene in dermatofibrosarcoma protuberans.