Fig. 5.

Immunohistochemical staining of EGFR, HER2 and VEGF in PDX tumor sections. Regions (brown areas) demonstrate high positive staining. Images A, B and C show moderate EGFR expression (IHC 1+), images D, E and F demonstrate high HER2 expression (IHC 2+), G and H images show overexpression of VEGF overexpression (IHC 3+) and image I shows negative staining for VEGF (IHC 0). The boxed areas illustrate higher magnification of the tumor sections. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)