Platelet‐derived growth factor receptors and ligands are up‐regulated in paediatric fibromatoses

Abstract

Platelet-derived growth factors (PDGF) and their receptors (PDGFR) play an essential role in pathways involved in the regulation of cell proliferation, growth and function. Overexpression of PDGF/R is reported in a wide range of solid tumours. The aim was to determine levels of PDGF/R expression in paediatric fibromatoses and myofibromatosis. Quantitative real-time polymerase chain reaction was used to examine the expression level of alpha and beta isoforms of PDGF/R in 17 fibromatoses, four myofibromatoses and three dermatofibrosarcoma protuberans (DFSP) in children. Fifteen of 17 (88%) fibromatoses and all myofibromatoses and DFSPs demonstrated increased expression of PDGFalpha and beta compared with a panel of normal tissues. In terms of the cognate receptors, 13/17 (76%) fibromatoses demonstrated increased expression for PDGFRalpha and Rbeta, whereas 3/4 myofibromatoses demonstrated increased expression of PDGFRalpha and all four had increased PDGFRbeta expression. All DFSPs were associated with increased expression of both PDGFRalpha and PDGFRbeta compared with normal control tissues. Increased expression of PDGF/Ralphabeta may play an important role in the mechanism of growth of these paediatric fibromatous lesions and warrants further investigation, since novel therapeutic interventions could potentially be developed in the light of the expression patterns.