Figure 3.

U87-EGFRvIII cell line in heterotransplantation models treated with negative control, 6 Gy radiation, and combined treatment with radiosurgery and temozolomide. (A) Bioluminescence images from heterotransplantation models (magnification, ×40) treated with negative control, 6 Gy radiation (48 h after treatment with 6 Gy peripheral doses by radiosurgery with 99% of isodose) and combined treatment with radiosurgery and temozolomide (cells were treated for 24 h with temozolomide at the IC₅₀ dose for 24 h after 6 Gy radiation) at 7, 14 and 21 days subsequent to tumour development. (B) Histological sections of tumor xenografts were excised and fixed in 10% neutral buffered formalin. Following paraffin embedding, 5-µm sections were cut and dried, deparaffinized, and rehydrated. Next, the nonspecific binding sites were blocked, and the slides were incubated at 4°C overnight in a 1:100 dilution of primary antibodies. Finally, the slides were incubated with a secondary antibody for 30 min. Immunohistochemistry for EGFRvIII and Ki-67 on xenograft tumour sections (Scale bar, 100 µm). (C) Evaluation of tumour growth curves. (D) Evaluation of weights of mice. (E) Improved survival observed in mice treated with the combined therapy. H&E, hematoxylin and eosin; TMZ, temozolomid; EGFRvIII, epidermal growth factor receptor variant III.