Elevated levels and altered fatty acid composition of plasma lysophosphatidylcholine(lysoPC) in ovarian cancer patients

Lysophosphatidylcholine (lysoPC), a product of phosphatidylcholine (PC) hydrolysis via phospholipase A activity, has been proposed to activate cells from a number of lineages, Here, we demonstrate that lysoPC levels are significantly elevated (by 43% overall, relative to normal controls) in the plasma of ovarian cancer patients. This does not appear to be common to all cancers as 5 out of 6 leukemia patients tested had markedly lower (less than one-half of normal) plasma lysoPC. In the plasma of ovarian cancer patients, the percentages of palmitoyl- and stearoyl-lysoPC species were significantly higher, whereas oleoyl and particularly linoleoyl/lysoPC were significantly lower than in control subjects. The molar ratios of lysoPC/PC and palmitoyl-lysoPC/linoleoy/lysoPC were also significantly elevated in the plasma of ovarian cancer patients compared with those of control subjects. Furthermore, the calculated value of plasma (lysoPC/PC) x (palmitoyl-lysoPC/linoleoyl lysoPC) was markedly higher in patients compared with controls.