In contrast to KCa2 and KCa3.1, the phylogenetically distantly related large-conductance voltage-gated and non-calmodulin-regulated KCa1.1 in human U251 glioblastoma cells was not blocked by 13b (Table S1) while flufenamic acid at 10 μM was found to potentiate KCa1.1 by 2.7-fold similar to a previous report [39] and caffeic acid at 10 μM had no blocking or activating effects (Table S1). This evidence concerns the gene KCNMA1 and glioblastoma.