Document Type : Research Articles
Department of Medicine, Gastroenterology Division, Federal University of Sao Paulo, Brazil.
Department of Surgery, Urology Division, Federal University of Sao Paulo, Brazil.
Department of Medicine, Gynecology Division, Federal University of Sao Paulo, Brazil.
Backgrounds: Colorectal (CRC) is one of the main cause of cancer worldwide. The search for noninvasive markers
for diagnosis and monitoring as the use of analytical technologies such as mass spectrometry (MS), which allowed the
search for lipid metabolites as candidates for probable biomarkers are needed. Objective and Methods: The objective
was to establish the lipid profile of patients with locally advanced, unresectable or metastatic CRC. Peripheral blood
was collected from patients with CRC and controls with normal colonoscopy. After lipid extraction, the samples were
processed and analyzed in the MALDI TOF / TOF equipment. From the data matrix, the statistical analyzes were
performed by the principal component analysis methods and the least squares discriminant analysis. The importance of
the variable in the projection was used to identify the ions that had the greatest discriminatory effect between the groups.
Results: Eight lipids were identified as potential biomarkers and a multiple logistic regression model was proposed
to calculate the performance of the test where we observed values of AUC 0.87, sensitivity 88.33% and specificity
83.78% and for a validation test with 1,000 permutations a p glycerophospholipids and policetidis. The strength of the association between the peak intensities of these lipids and
the presence of CRC make these metabolites candidates for possible biomarkers. The sphingolipid (m / z = 742.98869)
could be a biomarker in monitoring patients with CRC. In the survival analysis, three lipids showed a prognostic value
for colorectal cancer, sphingolipid (m / z = 857.11525) and policetidis (m / z = 876.20796) and glycerophospholipid
(m / z = 1031.54773).