Reply To Moestue Et Al.: Untangling The Contribution Of Choline Metabolism To The Metastatic Process

We thank Moestue et al. (1) for their insightful response to our article (2). Their critical comments regarding glycerophosphocholine (GPC) as a poorly understood clinical biomarker in breast cancer provide us with the perfect platform to discuss the relevance of GPC and EDI3, which cleaves GPC, for the tumorigenesis process. The schematic representation of lipid metabolism (Fig. 1) illustrates two factors important for tumor progression. First, proliferating and migrating tumor cells have higher demands for lipids to facilitate restructuring of cell membrane for division and migration. Therefore, high amounts of lipid precursors, such as GPC, are needed to facilitate the increased flux observed in various metabolic pathways, for example to supply phosphocholine to the Kennedy pathway during phosphatidylcholine synthesis. Second, some membrane lipids act as anchors for signaling …