GPCPD1 and melanoma: Interestingly the ratio of glycerophosphocholine (3.3 ppm) and phosphocholine (3.2 ppm) is different between melanoma and control group in the aqueous fraction (Figure 3); the melanoma group has higher ratios of glycerophosphocholine to phosphocholine (1:1) and glyerophosphocholine to choline (about 1:1.5), which indicates the possibility of an alteration in glycerophosphodiesterase (such as EDI3), which regulates interconversions between glycerophosphocholine and choline [52].