Preparation of 99Tcm-(HYNIC-BMS-200261)(tricine)(TPPTS) and its biodistribution and preliminary imaging study in nude mice bearing human breast cancer

Objective To synthesize 99Tcm-(HYNIC-BMS-200261)(tricine)(trisodium triphenylphosphine-3, 3', 3″-trisulfonate)(99Tcm-(HYNIC-BMS-200261)(tricine)(TPPTS)) and evaluate its biodistribution and feasibility of imaging in nude mice bearing human breast cancer xenografts. Methods HYNIC was conjugated to BMS-200261, then tricine and TPPTS were used as coligands for 99Tcm-labeling. The radiochemical purity and stability of 99Tcm-(HYNIC-BMS-200261) (tricine) (TPPTS) were measured with HPLC. Biodistribution in normal mice and imaging in nude mice bearing MDA-MB-435 breast cancer xenografts were performed respectively. Results The radiochemical purity of 99Tcm-(HYNIC-BMS-200261)(tricine)(TPPTS) was over 90%, and remained over 85% after 4 h at room temperature. The biodistribution data in normal mice showed a rapid clearance from blood. The tracer uptake of blood was (0.08±0.02) %ID/g at 2 h postinjection. 99Tcm-(HYNIC-BMS-200261)(tricine)(TPPTS) was excreted mainly via the liver and kidneys. There was little radioactivity accumulation in gastrointestinal tract. The tracer uptake of spleen, stomach and small intestine were (0.35±0.13), (0.27±0.11) and (0.25±0.07) %ID/g at 2 h postinjection. Gamma imaging showed the tumor tissue uptake was remarkable at 30 min postinjection, with the maximum T/NT ratio of 3.40±0.30 at 1 h postinjection. Conclusions 99Tcm-(HYNIC-BMS-200261)(tricine) (TPPTS) may be easily prepared with high radiochemical purity and stability. The imaging results and biodistribution characteristics suggest it may be promising for the detection of breast cancer. Key words: (HYNIC-BMS-200261)(tricine)-(TPPTS); Istope labeling; Technetium; Radionuclide imaging; Breast neoplasms; Mice