Serum fatty acid profiles in breast cancer patients following treatment

Abstract

Background: Breast cancer is associated with alterations in lipid metabolism. The treatment of breast cancer can also affect serum lipid composition. The purpose of this study was the examination of serum fatty acids (FAs) profiles in breast cancer survivors to assess if the FA levels normalize.

Methods: Serum levels of FAs were determined by gas chromatography-mass spectrometry in a group of breast cancer patients at baseline (before treatment, n = 28), at two follow-up visits at 12 months (n = 27) and 24 months (n = 19) after the breast cancer resection, and in the group of healthy controls (n = 25). Multivariate analysis was performed to assess how FA serum profile changes following treatment.

Results: Breast cancer patients' serum FA profiles at follow-ups did not normalize to the levels of control group. The greatest differences were found for levels of branched-chain (BCFA), odd-chain (OCFA) and polyunsaturated (PUFAs) FAs, all of which were significantly increased 12 months after the surgery.

Conclusions: After treatment for breast cancer, the patients' serum FA profile differs from the profile before treatment and from controls, especially 12 months after treatment. Some changes may be beneficial - increased BCFA and OCFA levels, and improved n-6/n-3 PUFA ratio. This may reflect lifestyle changes in breast cancer survivors and have an impact on the risk of recurrence.

Keywords: Breast cancer; Fatty acids; Gas chromatography-mass spectrometry; Lipids; Serum.

Fig. 1

The results of principal component analysis based on whole fatty acid profiles in serum of breast cancer patients at different stages of therapy and healthy controls

Fig. 2

Unsupervised principal component analysis (PCA) for two group comparisons. Models including whole serum FA profiles from (A) preoperative patients and 12 M follow-up (n = 27), B preoperative patients and 24 M follow-up (n = 19), C patients at 12 M follow-up and 24 M follow-up (n = 18), D preoperative patients (n = 28) and controls (n = 25), E patients at 12 M follow-up (n = 27) and controls (n = 25), F patients at 24 M follow-up (n = 19) and controls (n = 25)

Fig. 3

The serum fatty acid content [%] of main fatty acid groups in the serum of study subjects. p-values from All Pairwise Multiple Comparison Procedures (Tukey Test) or from Kruskal–Wallis One Way Analysis of Variance on Ranks followed by All Pairwise Multiple Comparison Procedures (Dunn's Method). BCFA: branched chain fatty acids; ECFA: even chain saturated fatty acids; MUFA: monounsaturated fatty acids; OCFA: odd chain saturated fatty acids; PUFA: polyunsaturated fatty acids; VLCFA – very long chain saturated fatty acids with > 20 carbons in acyl chain

Fig. 4

Results from partial least squares supervised analysis (PLS-DA). Models built using significantly different serum fatty acids in (A) preoperative patients and 12 M follow-up (n = 27), B preoperative patients and 24 M follow-up (n = 19), C patients at 12 M and 24 M follow-up (n = 18), D preoperative patients (n = 28) and control (n = 25), E patients at 12 M follow-up (n = 27) and controls (n = 25), F patients at 24 M follow-up (n = 19) and controls (n = 25). Fatty acids included as variables were selected based on significance in paired t-tests for comparisons between preoperative patients and follow-ups (see Tables S4, S5 and S6 respectively) or two-way t-Student’s test for comparisons between breast cancer patients and controls (Table S8)

Fig. 5

Alteration in selected classes of FA in breast cancer survivors suggests a therapeutic opportunity for suppressing cancer recurrence. Arrows up (↑:p < 0.05; ↑↑; p < 0.001) refer to a significantly higher concentration of FA and arrows down (↑:p < 0.05; ↓↓: p < 0.001) are related to a decreased level of FA, compared to healthy control. Mark (*) represents a contribution to tumor progression and ( +) antitumor properties of specific FA. Created with BioRender.com (accessed on 31 October 2022)