Therapeutic anti-EGFR antibody 806 generates responses in murine de novo EGFR mutant–dependent lung carcinomas
J. Clin. Invest. Danan Li, et al. 117:346 doi:10.1172/JCI30446 [Go to this article.]

Figure 2
Histopathological features of EGFRvIII-driven lung adenocarcinomas in mice treated with mAb806. (A) Lung adenocarcinoma driven by EGFRvIII expression for more than 8 weeks (top row). After 1 week of treatment with mAb806, tumors became smaller and had increased fibrosis (middle row). Lung specimens were grossly normal when mAb806 treatment ended at 5 weeks (bottom row). Arrows show a fibrotic nodule, consisting of fibroblasts and macrophages. No tumor cells were found in this particular fibrosis area. Original magnification, ×100 (left column), ×800 (right column). (B) Similar patterns and intensities of immunohistological staining of total EGFR can be observed in control mice and mice treated with mAb806 for 1 week (top- and bottom-left panels, respectively); intensity of phospho-EGFR staining of tumor cells decreased after 1 week of treatment (bottom-right panel) compared with that in untreated tumors (top-right panel). Representative photos were taken under ×200 magnification. (C) TUNEL staining shows an increase in the number of apoptotic nuclei (red arrows) in EGFRvIII-driven lung tumors after 1 week of treatment with mAb806 (bottom-left panel) compared with untreated tumors (top-left panel). Representative photos were taken under ×200 magnification. Data (expressed as mean ± SD) represent the apoptotic indices in lung tumors before and after 1 week of mAb806 treatment, determined from at least 200 high-power fields (HPF). Statistical analyses were performed using 2-tailed unpaired Student’s t test (right panel).