PLATELET-DERIVED GROWTH-FACTOR (PDGF) AND RECEPTOR (PDGFR) EXPRESSIONIN HUMAN MENINGIOMAS - CORRELATIONS WITH CLINICOPATHOLOGICAL FEATURESAND CYTOGENETIC ANALYSIS

PDGFs and their receptors expression were examined in a series of 46 m eningiomas by using specific monoclonal antibodies. The immunostaining was quantified by an image analyser and the results correlated with c linical and morphological data (histological type and grade). In addit ion, since the PDGFB chain is encoded by the c-sis proto-oncogene loca lized on chromosome 22 and because monosomy 22 has been frequently rep orted in meningiomas, PDGFs and PDGFRs expression have been correlated with cytogenetic analysis performed in 29 cases. The results demonstr ate PDGF A and PDGF B expression in most meningioma specimens and co-e xpression of these growth factors in numerous cells. PDGF A and B immu noreactivity was related to histological grade. PDGFR beta expression was strong in almost all meningiomas whereas PDGFR alpha was low. PDGF R alpha expression was related to tumour location and grade and PDGFR beta to histological subtype only. The cytogenetic analysis was not re lated to PDGFB chain expression. Taken together these data further con firm PDGF and PDGFR expression in human meningioma; PDGF may exist as an heterodimer (AB) as well as its receptor. The lack of correlation b etween cytogenetic analysis and PDGF values, the low level of PDGFB in recurrent meningiomas suggests that it is unlikely that the c-sis pro to-oncogene plays an important role in the genesis of meningiomas.