Evaluation of the internal therapeutic effectiveness of 131I-antiEGFR-BSA-PCL in nude mice with colorectal cancer / 中华放射医学与防护杂志

ABSTRACT

Objective To investigate the biological effects of internal radiation and therapeutic effectiveness of 131I-labeled anti-epidermal growth factor receptor (EGFR) in colorectal cancer of model mice.Methods Nano-liposome characterized for EGFR-targeting was constructed.The efficacy of cellular binding and uptake of the liposome was evaluated by the analysis of confocal microscopy observation and the iodide uptake assay.After intra-tumor injections of 74 MBq (740 MBq/ml) 131 I-antiEGFR-BSA-PCL,131 I-BSA-PCL,131 I or an equivalent volume of normal saline.The biological effects of internal irradiation and therapeutic efficacy of the liposomes on colorectal cancer modeled in a male BALB/c mouse were evaluated by means of tumor size,body weight,histopathology,and SPECT imaging.Results The confocal fluorescence images showed that the antiEGFR-BSA-PCL was successfully internalized into LS180 cells.The 131I uptake efficacy of 131I-antiEGFR-BSA-PCL was significantly higher than that of 131I-BSA-PCL in LS180 cells (t =2.77-5.40,P ＜ 0.01).Tumor size measurement showed that tumor growth was inhibited by the treatment with 131 I-EGFR-BSA-PCL and 131I-BSA-PCL,but had no significant differences between these two groups (P ＞0.05).It was found that the 131I-antiEGFR-BSA-PCL was markedly taken up by the tumor and reac hed its uptake value of (21.61 ± 1.0 1) and (20.58 ± 0.65)％ ID/g at 72 h following drug injection,which was higher than the uptake value of 131 I (t =9.36,8.69,P ＜ 0.01).SPECT imaging assay showed that,after being injected into mouse tumor,the 131 I-EGFR-BSA-PCL and 131I-BSA-PCL were uniformly distributed inside the tumor.Conclusions 131 I-antiEGFR-BSA-PCL obviously suppresses the development of colorectal cancer in mice.