Fig 1.
Typical 600 MHz 1H CPMG spectra of serum samples.
(A) controls (B) tumor-bearing mice. Keys for metabolites: 1, Lipids (mainly LDL); 2, Lipids (mainly VLDL); 3, Isoleucine; 4, Leucine; 5, Valine; 6, 3-Hydroxybutyrate; 7, Unknown; 8, Lactate; 9, Alanine; 10, Citrulline; 11, Arginine; 12, Acetate; 13, Proline; 14, Glutamate; 15, Glutamine; 16, Methionine; 17, Lipid; 18, Pyruvate; 19, Citrate; 20, Polyunsaturated fatty acid; 21, Asparagine; 22, Lysine; 23, α-Ketoglutarate; 24, Creatine; 25, Creatinine; 26, Choline; 27, Phosphocholine (PC) / Glycerophosphocholine (GPC); 28, Glucose; 29, TMAO (Trimethylamine-N-oxide); 30, Betaine; 31, Glycine; 32, Myo-inositol; 33, Glycerol; 34, Serine; 35, β-glucose; 36, α-glucose; 37, Urea; 38, Tyrosine; 39, Histidine; 40, Phenylalanine; 41, Formate.
Fig 2.
Typical 600 MHz 1H BPP-LED spectra of serum samples.
(A) controls (B) tumor-bearing mice. Keys for metabolites: 42, Cholesterol; 43, Lipids (mainly HDL); 44, Lipids (triglycerides and fatty acids); 45, O-acetyl glycoproteins; 46, Glycerolipids; 47, Phosphatidylcholine; 48, Triglyceride; 49, Unsaturated lipid.
Fig 3.
Multivariate analysis of CPMG spectra of serum samples of control and tumor—bearing mice.
(A) The score scatter plot of PCA for controls (black triangle) and tumor-bearing mice (red box). (B) PLS-DA showed a clear separation between controls (black triangle) and tumor-bearing mice (red box) in the score scatter plot. (C) Permutation test results for PLS-DA models (R2 = (0.0, 0.482), Q2 = (0.0, -0.214)). (D) Loading plot corresponding to PLS-DA score scatter plot.
Table 1.
Metabolites responsible for the differences between tumor-bearing mice and controls.
Fig 4.
Multivariate analysis of BPP-LED spectra of serum samples in control and tumor-bearing mice.
(A) The score scatter plot of PCA for controls (black triangle) and tumor-bearing mice (red box). (B) The score scatter plot of PLS-DA for controls (black triangle) and tumor-bearing mice (red box). (C) OPLS-DA showed clear separation between controls (black triangle) and tumor-bearing mice (red box) in the score scatter plot. (D) Permutation test results for PLS-DA models (R2 = (0.0, 0.56), Q2 = (0.0, -0.404)). (E) Loading plot corresponding to PLS-DA score scatter plot.
Fig 5.
Heat map of the 23 significantly changed serum metabolites in the control and tumor—bearing mice.
Fig 6.
ROC curves for distinguishing controls from tumor-bearing mice according to metabolite differences.