Anti-EGFR therapy radiosensitizes human lung adenocarcinoma xenograft in nude mouse / 中华放射肿瘤学杂志

ABSTRACT

Objective To investigate the effect of Gefitinib on radiosensitivity of human lung adenocarcinoma xenograft in nude mouse. Methods Human lung adenocarcinoma cell line A549 was used to establish nude mouse xenograft tumor model. The mice were derided into 4 groups control,irradiation alone, Gefinitib alone and radiation combined with Genifitib. Radiation schedule was 3 fractions of 5 Gy,once daily. Gefitinib was daily administered by gavage at 100 mg/( kg·day-1) for 14 days. In the combination group,radiotherapy was performed 2 hours after Gefitinib administration. Tumor diameter was measured every other day. Percentage of tumor growth inhibition, growth delay time and regrowth delay time were evaluated. Results For A549 xenografts in radiation alone, gefitinib alone and combination therapy groups, the percentage of tumor growth inhibition was 22.7%, 12.4% and 38.2%, respectively (F=25.75, P=0.000). Tumor growth delay time was 6.0,7.8 and 21.6 days,respectively(F=70.49,P=0.000). Tumor regrowth delay time in combination therapy and irradiation alone groups was 23.4 and 10.2 days. (F=174.24, P= 0.000). Sensitizing enhancement ratio of combinantion group was 1.5 in growth and 1.7 in regrowth. Conclusions Anti-EGFR therapy enhances the radiosensitivity of human lung adenocarcinoma xenograft in nude mouse.