An overexpression of fibroblast growth factor (FGF) and FGF receptor 4 in a severe clinical phenotype of facioscapulohumeral muscular dystrophy

We evaluated the expression of a select panel of growth factors and their r eceptors, including fibroblast growth factor 1 (FGF-1), fibroblast growth f actor 2 (FGF-2), platelet-derived growth factor (PDGF), FGF receptor 1 (FGF -RI), FGF receptor 3 (FGF-R3), FGF receptor 4 (FGF-R4), PDGF receptor alpha (PDGF-R alpha), PDGF receptor beta (PDGF-R beta), and heparan sulfate prot eoglycan (HSPG), in muscle biopsy specimens from nine facioscapulohumeral m uscular dystrophy (FSHD) patients using immunohistochemistry. Two cases of Duchenne-type muscular dystrophy (DMD), two of Becker-type muscular dystrop hy (BMD), and one of limb-girdle-type muscular dystrophy (LGMD) were also i nvestigated. Widespread immunostaining for FGF-1 and FGF-2 on the sarcolemm a and overexpression of FGF-R4 in endomysial and perimysial connective tiss ue were seen in one patient with a severe clinical phenotype of FSHD who ha d respiratory failure. Standard histochemistry in this patient revealed mar ked interstitial fibrosis and lobulated fibers. The overexpression of FGF a nd FGF-R4 in this severe FSHD case may be associated with the muscle fibros is and disease severity, (C) 2000 John Wiley & Sons, Inc.