Discovery of Urinary Biomarkers in Patients with Breast Cancer Based on Metabolomics

A metabolomics study was conducted to identify urinary biomarkers for breast cancer, using gas chromatographymassspectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS), analyzed by principal components analysis(PCA) as well as a partial least squares-discriminant analysis (PLS-DA) for a metabolic pattern analysis. To find potentialbiomarkers, urine samples were collected from before- and after-mastectomy of breast cancer patients and healthy controls. Androgens, corticoids, estrogens, nucleosides, and polyols were quantitatively measured and urinary metabolic profiles wereconstructed through PCA and PLS-DA. The possible biomarkers were discriminated from quantified targeted metabolites with ametabolic pattern analysis and subsequent screening. We identified two biomarkers for breast cancer in urine, β-cortol and 5-methyl-2-deoxycytidine, which were categorized at significant levels in a student t-test (p-value < 0.05). The concentrations ofthese metabolites in breast cancer patients significantly increased relative to those of controls and patients after mastectomy. Biomarkers identified in this study were highly related to metabolites causing oxidative DNA damage in the endogenous metabolism. These biomarkers are not only useful for diagnostics and patient stratification but can be mapped on a biochemical chartto identify the corresponding enzyme for target identification via metabolomics. KCI Citation Count: 0