Therapy of cervical cancer using 131I-labeled nanoparticles.

Objective To evaluate the effectiveness of two kinds of Arg-Gly-Asp (RGD)-targeted 131I-containing nanoliposomes for the treatment of cervical cancer in vitro and in vivo. Methods The nanoparticle liposomes designated RGD-131I-tyrosine peptide chain (TPC)-L and 131I-RGD-L were prepared. The emulsion solvent evaporation method was used to encapsulate the polypeptide into liposomes. The quantity of entrapped polypeptide was measured using UV spectrophotometry. The labeling rates, radiochemical purities, and total radioactivities were measured using paper chromatography. Cytotoxicity was assessed using the MTS assay and flow cytometry. Therapeutic efficacy was monitored using a mouse xenograft model of cervical cancer. Results The labeling efficiency, radiochemical purity, and specific radioactivity of RGD-131I-TPC-L were greater than those of 131I-RGD-L. The cytotoxicity test indicated that late apoptosis of cells treated with RGD-131I-TPC-L and 131I-RGD-L was higher than that of cells treated with Na131I. The therapeutic effect of RGD-131I-TPC-L was better than that of 31I-RGD-L in the mouse model. Conclusions The specific activity of liposome-encapsulated RGD-131I-TPC-L was higher than that of 131I-RGD-L, which labeled liposomes directly. Moreover, the RGD-131I-TPC-L liposomes were more effective for killing xenografted tumor cells.