Expression and mutational status of PDGFR in thymic tumours.
BACKGROUND
There is an ongoing search for new therapeutic targets in invasive non-resectable thymic tumours because of the low response rates in current chemotherapeutic treatment modalities. In this study, the possibility that platelet-derived growth factor receptor A (PDGFRA) and/ or PDGFRB may represent potential therapeutic targets in epithelial tumours of the thymus was investigated.


METHODS
Tissue samples were obtained by thymectomy from 36 different patients with epithelial tumours of the thymus (26 thymomas types A, AB, B1-3 and 10 thymic carcinomas). Normal thymi from three young children were used as controls. The PDGFRA and PDGFRB protein expressions as well as the mutational statuses of exons 12, 14 and 18 of the PDGFRA gene were analyzed.


RESULTS
All the subtypes of thymomas and the thymic carcinomas showed staining for PDGFRA, but no mutations in the known mutational hotspots were identified. Only about one third of the tumours stained for PDGFRB. PDGFRA and PDGFRB protein staining were slightly positively correlated.


CONCLUSIONS
PDGFRA may represent a potential therapeutic target in thymic tumours.
Translational Research Unit, Thoraxklinik-Heidelberg gGmbH, University of Heidelberg, Amalienstr. 5, 69126 Heidelberg, Germany. michael.meister@thoraxklinik-heidelberg.de
Michael
M
Meister
Philip
P
Kahl
Thomas
T
Muley
Alicia
A
Morresi-Hauf
Christian
C
Sebening
Michael A
MA
Kern
Marco
M
Breinig
Philipp
P
Schnabel
Hendrik
H
Dienemann
Peter
P
Schirmacher
Ralf J
RJ
Rieker
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004252:DNA Mutational Analysis; D005091:Exons; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D020796:Receptor, Platelet-Derived Growth Factor alpha / Q000096:biosynthesis* / Q000235:genetics*; D020797:Receptor, Platelet-Derived Growth Factor beta / Q000096:biosynthesis* / Q000235:genetics*; D013953:Thymus Neoplasms / Q000201:enzymology* / Q000235:genetics / Q000473:pathology
D020796:Receptor, Platelet-Derived Growth Factor alpha; D020797:Receptor, Platelet-Derived Growth Factor beta