IL13RA2 and glioblastoma: Interleukin IL-13 is expressed in glioblastoma; it binds to two receptors, IL-13Rα1 and IL-13Rα2, and mediates a variety of different effects on various cell types, including B cells, neutrophils, monocytes, natural killer cells, endothelial cells, and fibroblasts [63,64].