FIGURE 5.

Relative mRNA expression of ErbB4-processing proteases in MB, PA and normal brain. RNA samples representing normal brain tissues (cerebellum and total brain), 31 MB tumours and 35 PA tumours were analyzed for transcripts encoding TACE and components of the γ-secretase complex (Presenilin-1, Presenilin-2, Nicastrin, Pen-2 and Aph1a). Expression of 18S rRNA was used to normalize protease expression. SDs of two parallel analyses were < 5% of the means. MB, medulloblastoma; PA, pilocytic astrocytoma; TACE, tumour necrosis factor-α-converting enzyme.