Blood and urine biomarkers in invasive ductal breast cancer: Mass spectrometry applied to identify metabolic alterations

Abstract Specific classes of biomolecules may act as putative biomarkers in altered metabolic pathways related to breast cancer diagnosis, classification, and prognosis. This study aim an integrated metabolomic profiling of blood serum and urine from invasive ductal ER+ breast cancer cases (stage 2 and 3) and matched controls, using high performance liquid chromatography coupled with mass spectrometry. More than 400 metabolites were identified in both biofluids, either common (96 molecules) or specific molecules found only in blood serum or urine (109 and 136 molecules, respectively). Using the Metaboanalyst 5.0 software, by multi- and univariate analysis, the most significant biomolecules were selected for discrimination between the groups and for cancer staging. Polar molecules (amino acids, tryptophan metabolites, nucleosides) and lipids (free fatty acids, acyl carnitines, estrogen metabolites, choline-dependent glycerophospholipids and lysophosphatidyl derivatives, ceramides) were considered as significant, putative biomarkers of altered metabolic pathways. The biological significance of these findings will be amplified by further analysis of larger cohorts of patients and will be essential for the prospective evaluation and early diagnosis of breast cancer.