Certain receptors are often overexpressed during
tumor occurrence and development and closely correlate with
carcinogenesis. Owing to its overexpression on the cell membrane and cytoplasm of various
tumors,
plectin, which is involved in
tumor proliferation, migration, and invasion, has been viewed as a promising target for
cancer imaging. Hence,
plectin-targeting agents have great potential as imaging probes for
tumor diagnosis. In this study, we developed a [99mTc]Tc-labeled
plectin-targeted
peptide (PTP) as a novel single-photon emission computed tomography (SPECT) probe for
tumor imaging and investigated its pharmacokinetics, biodistribution, and targeting ability in several types of
tumor-bearing mouse models. The PTP had good biocompatibility and targeting ability to
tumor cells in vitro and could be readily labeled with [99mTc]Tc after modification with the bifunctional
chelator 6-hydrazino
nicotinamide (HYNIC). Furthermore, the prepared [99mTc]Tc-labeled PTP ([99mTc]Tc-HYNIC-PTP) showed high radiochemical purity and excellent stability in vitro. In addition, favorable biodistribution, fast blood clearance, and clear accumulation of [99mTc]Tc-HYNIC-PTP in several types of
tumors were observed, with a good correlation between
tumor uptake and
plectin expression levels. These results indicate the potential of [99mTc]Tc-HYNIC-PTP as a novel SPECT probe for
tumor imaging.