Abnormal serum lysophospholipids in multiple myeloma patients

Lysophosphatidylcholine (LPC) and lysophosphatidic acid (LPA) mediate vario us kinds of biological activities and play an important role in cellular si gnal transduction. We analyzed serum phospholipids obtained from 16 multipl e myeloma (MM) patients and observed that serum LPA level was significantly higher in MM patients (5.3 +/- 0.5 nmol/mL) than in normal controls (1.7 /- 0.3 nmol/mL). LPC level was also higher than that in normal controls, an d it correlated significantly with the concentration of LPA (r = 0.678, P < 0.01). In MM patients, palmitic acid/linoleic acid ratios in phosphatidylc holine and LPC were higher than those in normal controls. In the 12-mon fol low-up study of two patients with the immune globulin G type, we recognized that the increase of LPC, LPA, and arachidonic acid/linoleic acid ratio in phosphatidylinositol corresponded with a decline in the serum albumin leve l and choline esterase activity.