A Novel Three Serum Phospholipid Panel Differentiates Normal Individuals from Those with Prostate Cancer

BACKGROUND: The results of prostate specific antigen (PSA) and digital rectal examination (DRE) screenings lead to both under and over treatment of prostate cancer (PCa). As such, there is an urgent need for the identification and evaluation of new markers for early diagnosis and disease prognosis. Studies have shown a link between PCa, lipids and lipid metabolism. Therefore, the aim of this study was to examine the concentrations and distribution of serum lipids in patients with PCa as compared with serum from controls. METHOD: Using Electrospray ionization mass spectrometry (ESI-MS/MS) lipid profiling, we analyzed serum phospholipids from age-matched subjects who were either newly diagnosed with PCa or healthy (normal). RESULTS: We found that cholester (CE), dihydrosphingomyelin (DSM), phosphatidylcholine (PC), egg phosphatidylcholine (ePC) and egg phoshphatidylethanolamine (ePE) are the 5 major lipid groups that varied between normal and cancer serums. ePC 38:5, PC 40:3, and PC 42:4 represent the lipids species most prevalent in PCa as compared with normal serum. Further analysis revealed that serum ePC 38:5 ≥0.015 nmoles, PC 40.3 ≤0.001 nmoles and PC 42:4 ≤0.0001 nmoles correlated with the absence of PCa at 94% prediction. Conversely, serum ePC 38:5 ≤0.015 nmoles, PC 40:3 ≥0.001 nmoles, and PC 42:4 ≥0.0001 nmoles correlated with the presence of PCa. CONCLUSION: In summary, we have demonstrated that ePC 38:5, PC 40:3, and PC 42:4 may serve as early predictive serum markers for the presence of PCa.