To verify that the effect of TRAM-34 was due to its specific inhibition of KCa3.1 activity, GL261, U87MG and primary glioblastoma cells (GBM18) were silenced for KCa3.1 expression with IPTG-inducible shRNA constructs, treated with TMZ and analyzed for viability. This evidence concerns the gene KCNN4 and glioblastoma.