Choline-phospholipids inter-conversion is altered in elderly patients with prostate cancer

Area of Science:

• Biochemistry
• Oncology
• Metabolomics

Background:

• Choline is vital for phospholipids and methyl groups in cells.
• Malignant cells have high demands for methyl and phospholipids, suggesting altered choline metabolism in cancer patients.

Purpose of the Study:

• To investigate differences in choline metabolite concentrations between elderly men with prostate cancer (PCa) and benign prostatic hyperplasia (BPH).
• To assess plasma/serum levels of free choline, betaine, dimethylglycine, folate, total homocysteine (tHcy), cystathionine, methylmalonic acid, S-adenosyl homocysteine (SAH), S-adenosyl methionine (SAM), and phospholipids.

Main Methods:

• A case-control study involving 80 men with PCa and 51 men with BPH (age ≥ 65 years).
• Measurement of plasma/serum concentrations of various choline metabolites and phospholipids.

Main Results:

• No significant differences in free choline, folate, tHcy, SAH, or phosphatidylcholine between PCa and BPH groups.
• Significantly lower concentrations of various sphingomyelin species were observed in men with PCa compared to controls (6-16% differences).
• Multiple regression analysis identified PCa, statin use, choline, age, cystathionine, and methylmalonic acid as negative determinants of sphingomyelins, while phosphatidylcholine was a positive determinant.

Conclusions:

• Results suggest systemic alterations in phospholipid metabolism in PCa.
• A significant decrease in plasma sphingomyelin concentrations was found in elderly men with PCa and statin users, with a synergistic effect observed.
• PCa was not associated with significant changes in plasma choline or methyl metabolites, though altered absorption/uptake cannot be excluded.