Therapy of cervical cancer using (131)I-labeled nanoparticles

OBJECTIVE: To evaluate the effectiveness of two kinds of Arg-Gly-Asp (RGD)-targeted (131)I-containing nanoliposomes for the treatment of cervical cancer in vitro and in vivo. METHODS: The nanoparticle liposomes designated RGD-(131)I-tyrosine peptide chain (TPC)-L and (131)I-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-(131)I-TPC-L were greater than those of (131)I-RGD-L. The cytotoxicity test indicated that late apoptosis of cells treated with RGD-(131)I-TPC-L and (131)I-RGD-L was higher than that of cells treated with Na(131)I. The therapeutic effect of RGD-(131)I-TPC-L was better than that of (31)I-RGD-L in the mouse model. CONCLUSIONS: The specific activity of liposome-encapsulated RGD-(131)I-TPC-L was higher than that of (131)I-RGD-L, which labeled liposomes directly. Moreover, the RGD-(131)I-TPC-L liposomes were more effective for killing xenografted tumor cells.