%0 Journal Article %T Assessment of epidermal growth factor receptor status in glioblastomas %J Asia Oceania Journal of Nuclear Medicine and Biology %I Mashhad University of Medical Sciences in collaboration with AOFNMB %Z 2322-5718 %A Zhu, Hui-Jun %A Sakahara, Harumi %A Ogawa, Mikako %A Magata, Yasuhiro %A Ohmomo, Yoshiro %A Hirata, Masahiko %A Namba, Hiroki %D 2013 %\ 10/01/2013 %V 1 %N 2 %P 47-52 %! Assessment of epidermal growth factor receptor status in glioblastomas %K [125I]PYK %K gefitinib %K EGFR %K Glioblastoma %R 10.7508/aojnmb.2013.02.007 %X Objective(s): Our previous study showed that a newly designed tracer radioiodinated 6-(3-morpholinopropoxy)-7-ethoxy-4-(3'-iodophenoxy)quinazoline ([125I]PYK) is promising for the evaluation of the epidermal growth factor receptor (EGFR) status and prediction of gefitinib treatment of non-small cell lung cancer. EGFR is over-expressed and mutated also in glioblastoma. In the present study, the expressions and mutation of EGFR were tested with [125I] PYK in glioblastoma in vitro and in vivo to determine whether this could be used to predict the sensitivity of glioblastoma to gefitinib treatment. Methods: Glioblastoma cell lines with different expression of EGFR were tested. Growth inhibition of cell lines by gefitinib was assessed by the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) colorimetric assay. Uptake levels of [125I]PYK were evaluated in cell lines in vitro. Tumor targeting of [125I]PYK was examined by a biodistribution study and imaging by single photon emission computed tomography (SPECT). Results: High concentrations of gefitinib were needed to suppress EGFR-mediated proliferation. The uptake of [125I] PYK in cell lines in vitro was low, and showed no correlation with EGFR expression or mutation status. Biodistribution study and SPECT imaging with [125I]PYK for xenografts showed no [125I]PYK uptake. Conclusion: The results showed prediction of gefitinib effectiveness was difficult in glioblastoma by [125I]PYK, which might be due to the complicated expression of EGFR status in glioblastoma. Thus, new tracers for sites downstream of the mutant EGFR should be investigated in further studies. %U https://aojnmb.mums.ac.ir/article_1601_a4d4600ae0b1f53cad193dc1abbec1de.pdf