Figure 4

Decreased IL-13Rα2 expression through IL-13-PE immunotoxin treatment. (A) Western blot showing decreased expression of IL-13Rα2 in SCCs from IL-13-PE treated mice when compared to the corresponding control SCCs. Tumors developed from different locations in the head and neck epithelium such as the tongue, muzzle, and ear. (B) Tumors from the muzzle and ear of the IL-13-PE treated mice show a significant decrease (P value < 0.05) in relative IL-13Rα2 expression compared to the non-treated mice. (C) Immunohistochemistry shows a general decrease in IL-13Rα2 expression on a tumor from the ear of an IL-13-PE treated mouse as compared to the control but, of the cancer cells that escaped cell death by IL-13-PE, there was no change in p-Akt, a genetic change induced by Pten deletion, nor was there any difference in active proliferation through Ki67 staining.