The Synthesis and Initial Evaluation of MerTK Targeted PET Agents

MerTK (Mer tyrosine kinase), a receptor tyrosine kinase, is ectopically or aberrantly expressed in numerous human hematologic and solid malignancies. Although a variety of MerTK targeting therapies are being developed to enhance outcomes for patients with various cancers, the sensitivity of tumors to MerTK suppression may not be uniform due to the heterogeneity of solid tumors and different tumor stages. In this report, we develop a series of radiolabeled agents as potential MerTK PET (positron emission tomography) agents. In our initial in vivo evaluation, [F-18]-MerTK-6 showed prominent uptake rate (4.79 +/- 0.24%ID/g) in B16F10 tumor-bearing mice. The tumor to muscle ratio reached 1.86 and 3.09 at 0.5 and 2 h post-injection, respectively. In summary, [F-18]-MerTK-6 is a promising PET agent for MerTK imaging and is worth further evaluation in future studies.

Automated summary

MerTK is abnormally expressed in various cancers, but the sensitivity of tumors to MerTK suppression may vary. In this study, a radiolabeled agent [F-18]-MerTK-6 was developed and showed prominent uptake in tumors in initial evaluation, suggesting it as a promising PET agent for MerTK imaging.