Suppression of EGFRvIII tyrosine phosphorylation by combination treatment with nimotuzumab and temozolomide (TMZ) in U87MG.∆EGFR in vitro (A) and in vivo (B, C). A. Cultured U87MG.∆EGFR and U87MG.wtEGFR cells were treated with nimotuzumab and TMZ in vitro, and their total cell lysates were subjected to Western blot analysis. Treatments are as follows: ‐, DMSO control; N, nimotuzumab 1 μM; T, TMZ 20 μM; NT, nimotuzumab; and TMZ combination. B, C. Dephosphorylation of EGFRvIII in mice subcutaneous (B) or intracerebral (C) xenografts upon treatments with either vehicles (V), nimotuzumab alone (N), TMZ alone (T), or both (NT) as described in “Materials and Methods.” Relative tyrosine phosphorylation per molecule is shown below each lane and calculated as a ratio of that of either untreated or vehicle‐treated status and is also standardized with actin expression.