Expression of epidermal growth factor receptor and its relationship to apoptosis in myelodysplastic syndromes

To explore the expression of epidermal growth factor receptor (EGFR) in hematopoietic cells and investigate its relationship to apoptosis in myelodysplastic syndrome (MDS) patients. Mononuclear cells from 18 MDS patients were used to analyze the expression of EGFR and the apoptotic signals by immunocytochemical technique and TdT-mediated dUTP nick end labelling (TUNEL) fluorescein. Flow cytometry (FCM) sorted CD(34)(+) cells from 15 MDS cases and 6 normal donors were also analyzed for the EGFR expression and apoptotic signals. Nine normal marrow samples were taken as controls. EGFR expression and its relationship to apoptosis were analysed. (1) There was a higher EGFR expression rate (38.6 +/- 24.6)% in nucleated cells of MDS marrow than in normal marrow (18.1 +/- 14.0)% (P < 0.05). (2) Apoptosis occurred much more in EGFR negative cells (16.1%) than in EGFR positive cells (1.4%) (P < 0.01). EGFR expression showed negative correlation with apoptosis (r = -0.701; t(r) = 3.60; P < 0.01). (3) In CD(34)(+) cells,