Evaluation of Tc-Labeled Bevacizumab-HYNIC Conjugate in Human Ovarian Tumor Xenografts.

The aim of the present investigation was to examine the suitability of Tc--HYNIC-BZMB as a specific vascular endothelial growth factor (VEGF)-targeting agent. Bevacizumab is a recombinant humanized monoclonal antibody that inhibits VEGF. hydroxysuccinimide-2-hydrazinonicotinic acid (-HYNIC) was conjugated to BZMB, followed by labeling with Tc using -[Tris(hydroxymethyl)methyl] glycine (tricine), ethylenediamine-,'-diacetic acid (EDDA), and nicotinic acid as coligands. Tc-labeled BZMB was characterized in terms of TcO, radiocolloids, and labeled -HYNIC-BZMB using thin-layer chromatography and HPLC. Poor metastatic SKOV-3 and high metastatic SKOV-3.ip1 human ovarian cancer cell lines were used for binding uptake of Tc--HYNIC-BZMB. Biodistribution and scintigraphy accuracy were examined in human ovarian tumor xenografts in rats and rabbits. Tc--HYNIC-BZMB prepared by using a mixture of tricine and EDDA demonstrated relatively high radiochemical purity (more than 98%). In L-cysteine and serum, it exhibited a stable behavior up to 16 h. binding uptake indicated that it targets high metastatic SKOV-3.ip1 tumors. Biodistribution in human ovarian tumor xenografts in rats confirmed a significant uptake in SKOV-3.ip1 tumors (5.69% ± 1.86%, 4 h). Scintigraphic accuracy in human ovarian tumor xenografts in rabbits validated its suitability as a high metastatic SKOV-3.ip1 radiotracer. High radiochemical purity, stability in saline and serum, biodistribution, and scintigraphy of Tc--HYNIC-BZMB in human ovarian tumor xenografts in rats and rabbits confirmed its suitability as a potential radiotracer for imaging high metastatic SKOV-3.ip1 sites.