Fluorine-18 Labelled Radioligands for PET Imaging of Cyclooxygenase-2

Abstract

Molecular imaging probes enable the early and accurate detection of disease-specific biomarkers and facilitate personalized treatment of many chronic diseases, including cancer. Among current clinically used functional imaging modalities, positron emission tomography (PET) plays a significant role in cancer detection and in monitoring the response to therapeutic interventions. Several preclinical and clinical studies have demonstrated the crucial involvement of cyclooxygenase-2 (COX-2) isozyme in cancer development and progression, making COX-2 a promising cancer biomarker. A variety of COX-2-targeting PET radioligands has been developed based on anti-inflammatory drugs and selective COX-2 inhibitors. However, many of those suffer from non-specific binding and insufficient metabolic stability. This article highlights examples of COX-2-targeting PET radioligands labelled with the short-lived positron emitter 18F, including radiosynthesis and PET imaging studies published in the last decade (2012–2021).

Up-and-coming Radiotracers for Imaging Pain Generators

“… 64 Other major drawbacks of the previous radiotracers include substantial defluorination in the case of [18F] tracers, significant defluorination in the case of [18F] tracers, high nonspecific binding, low COX-2 affinity, and others. 63 65 More recently, a novel cyclooxygenase-2 PET radioligand, [11C]MC1, was developed that did show upregulation in primate neuroinflammation and in human peripheral tissue with inflammation. 66 Another new radioligand, [18F]MTP, is a potential candidate for COX-2 imaging in clinical studies of neuroinflammation, but more research is needed before clinical translation is possible ( Fig.…”