Jashim Uddin, Ph.D., Lawrence Marnett, Ph.D., and colleagues are developing novel imaging agents that selectively bind to COX-2. In work featured on the cover of the October issue of Cancer Prevention Research, they describe a series of novel fluorine-containing compounds derived from indomethacin or celecoxib that selectively inhibit COX-2. Incorporation of radioactive fluorine (18-F) into one of these compounds provided sufficient signal for in vivo positron emission tomography (PET) imaging.
The 18-F compound was detected at sites of inflammation in animal models, but not in mice missing COX-2. In mice bearing both COX-2-positive and COX-2-negative human tumors, the 18-F compound accumulated only in the COX-2-positive tumor.
The findings suggest that this first COX-2-targeted PET imaging agent will be useful for early detection of cancer and for evaluation of the COX-2 status of pre-malignant and malignant tumors.