TY - JOUR T1 - Prediction of Synergistic Antitumour Effect of Gefitinib and Radiation <em>In Vitro</em> JF - Anticancer Research JO - Anticancer Res SP - 2883 LP - 2888 VL - 31 IS - 9 AU - HUI QIANG LIN AU - HAIDER MERIATY AU - ANDREW KATSIFIS Y1 - 2011/09/01 UR - http://ar.iiarjournals.org/content/31/9/2883.abstract N2 - Aim: This study investigated the potential of a series of biomarkers in predicting the interaction of gefitinib and radiation in tumour treatment. Materials and Methods: In vitro assays were performed on human skin cancer and melanoma cell lines. The antitumour effect was measured by using the MTT assay. Total and phosphorylated epidermal growth factor receptor (EGFR and pEGFR) levels were determined by cell-based ELISA. Results: Gefitinib and radiation interacted to inhibit tumour cell proliferation in a cell line-dependent manner. Synergism dominated the interaction (76%), followed by additive effect (20%) and a few instances of antagonism (4%). Correlation analyses revealed a significant correlation between the median combination index (CI) and gefitinib IC50, radiation ID50, gefitinib- or EGF-modulated EGFR and/or pEGFR expression (all p≤0.05). Conclusion: A potential role of gefitinib efficacy, radiation efficacy and gefitinib- or EGF-modulated EGFR and/or pEGFR expression in the prediction of interaction between gefitinib and radiation is supported. ER -