Definition

A phospholipid ether analog labeled with iodine I 124, with a potential imaging property upon positron emission tomography (PET). Upon administration, iodine I 124 NM404 selectively accumulates in and is retained within tumor cells for a prolonged period of time due to the decreased activity of a phospholipase D (PLD), most likely isoform 1 of PLD, in tumor cells compared to normal cells. As tumor cells are unable to metabolize and eliminate MN404, tumor cells can be visualized upon PET imaging. In addition, iodine I 124 NM404 may provide a more accurate image of the tumor than imaging with the current standard. PLD is an enzyme found in the cell membrane of normal cells that degrades phospholipids.