Prognostic value of plasma: transforming growth factor-beta in patients with glioblastoma multiforme

We investigated whether the postoperative concentration of circulating tran sforming; growth factor beta (TGF-beta) yields prognostic value in patients with glioblastoma multiforme (gbm). Blood was collected from 20 healthy vo lunteers and in 28 patients with mainly glioblastoma multiforme (gbm), both before radiotherapy, during and after 4 weeks of irradiation. Both latent and active TGF-beta were quantified directly in the blood plasma using a bi oassay with mink lung epithelial cells transfected with a plasminogen activ ator inhibitor-1 promotor luciferase construct. The average plasma concentr ation of TGF-beta before radiotherapy for gbm patients was 26.2 ng/ml, whic h was significant higher than in normal controls (16.2 ng/ml, p=0.02). No c orrelation was found between TGF-beta and survival, nor between plasma TGF- betaB and the diameter of the postoperative contrast-enhancing lesion. The pattern of plasma TGF-beta during radiotherapy did not correlate with the c linical course of patients, nor with the fractionation scheme. Plasma TGF-b eta did not reveal a clinical useful prognostic value for gbm patients, whi ch is partly due to the large variation in TGF-betaB plasma levels between individual patients.