SP94 peptide as a specific probe for hepatocellular carcinoma imaging / 中华核医学与分子影像杂志

ABSTRACT

Objective To investigate the capability of 99 Tcm?tricine?EDDA/HYNIC?SFSIIHTPILPL ( SP94) as a specific probe for HCC imaging. Methods HYNIC?SP94 peptide was prepared by solid phase synthesis, followed by 99 Tcm labeling with tricine?EDDA as the coligand. After determination of radiochemical purity and stability, cell binding study was carried out by incubating Huh?7 cells with 99 Tcm?tricine?EDDA/HYNIC?SP94 at different specific activities (2.5, 4.0 and 30.0 GBq/μmol). The biodistribution studies and microSPECT/CT imaging were performed in Huh?7 tumor?bearing mice ( study group) and Hela tumor?bear?ing mice ( control group ) . Statistical analysis was by two?sample t test. Results 99 Tcm?tricine?EDDA/HYNIC?SP94 was synthesized with over 95% of labeling yield, which remained stable in saline and FBS up to 12 h. With increasing concentrations of 99 Tcm?tricine?EDDA/HYNIC?SP94, Huh?7 cell binding increased but became gradually saturated. In biodistribution studies, (1.02±0.26) %ID/g of tracer was accumulated in Huh?7 tumors at 0.5 h after injection of 99 Tcm?tricine?EDDA/HYNIC?SP94, higher than that in the HYNIC?SP94 blocking group ((0.34±0.09) %ID/g;t=3.537, P<0.05). Compared to Hela tumors, Huh?7 tumors were clearly visualized by microSPECT/CT, with which better imaging quality could be achieved with higher specific radioactivity. Conclusion 99 Tcm?tricine?EDDA/HYNIC?SP94 could achieve a high labeling effi?ciency and good in vitro stability as a potential diagnostic tracer specifically targeted for HCC.