Fig. 4.

Intratumoural survivin/BIRC5 expression in relation to survival of patients with GBM. Kaplan-Meier survival analyses showing BIRC5 gene expression (A) as well as survivin protein expression (B) in GBM tissue samples in relation to the survival pattern of patients with GBM. Molecular analysis of BIRC5 gene transcription levels in GBM tissue was measured by real-time polymerase chain reaction, while survivin protein expression in paraffin-embedded GBM tissue sections was detected using immunohistochemistry. For BIRC5 gene transcription, low expression indicates a delta cycle threshold (CT) value of >6.4, while high expression indicates a delta CT value of <6.4. Twenty samples from patients with GBM were tested. ΔCT range was 3.56–10.00 and the median ΔCT value was 6.4. Thirteen samples exhibited ΔCT ≥ 6.4 and the remaining seven samples ΔCT <6.4.