Alternative splicing of fibronectin transcripts in osteochondrogenic tumors

Background: Fibronectin (FN) acts in many, fundamental biological processes including cell adhesion, migration, proliferation and apoptosis. Although FN shows an ubiquitous expression pattern, alternative mRNA splicing modula tes tissue-specific molecular hererogeneity at three regions: extra domain- B extra domain-A and variable region. Materials and Methods: In the present study, we analyzed the FN mRNA splicing in osteochondrogenic tumors as wel l as in various normal tissues using the RT-PCR method. Results: Normal car tilage almost exclusively contained short mRNA lacking alternative exons in all regions. However, 14 osteochondrogenic tumors including osteochondroma , enchondroma, chondroblastoma, chondrosarcoma and osteosarcoma uniformly c ontained long mRNA with various patterns of alternative exons in the three regions. Conclusion: These results indicated that the lack of regulation ex cluding the alternative exons may be associated with tumorigenesis in chond rocytes.