Study on the possibility of insulin as a carrier of IUdR for hepatocellular carcinoma-targeted therapy

摘要

AIM: To evaluate the possibility of using insulin as a carrier for carcinoma-targeted therapy mediated by receptor, and to investigate the expression of insulin receptor in human hepatocellular carcinoma and the receptor binding characteristics of insulin-IUdR (iododeoxyuridine).METHODS: IUdR was covalently conjugated to insulin.Receptor binding assays of 125Ⅰ-insulin to human hepatocellular carcinoma and its adjacent tissue were performed.Competitive displacements of 125Ⅰ-insulin by insulin and insulin-IUdR to bind to insulin receptor were respectively carried out. Statistical comparisons between the means were made with paired t-test at a confidence level of 95%.RESULTS: The data indicated that there were high- and low-affinity binding sites for 125Ⅰ-insulin on both hepatocellular carcinoma and its adjacent tissue. Hepatocellular carcinoma had a significantly higher Bmax for high affinity binding site than its adjacent liver tissue (P＜0.05, t=2.275). Insulin-IUdR competed as effectively as insulin with 125Ⅰ-insulin for binding to insulin receptor. Values of IC501, C502, KI1 and KI2 for Values of IC50l and KI1 for insulin-IUdR were significantly higher than that for insulin (P＜0.01,t=4.537 and 4.813).CONCLUSION: It is possible to use insulin as a carrier for carcinoma-targeted therapy mediated by receptor.