Is the Low-Resolution Mass Spectrometer Capable of Detecting Cancer at Early Stages?

Abstract

It is known that cancer promotes changes in the metabolites found in biofluids and, therefore, the early detection of these metabolites allows for the best prognosis of the disease. Since ESI-MS fingerprinting has proved to be an excellent tool for ‘‘first pass’’ metabolome analysis of complex biological samples, we have presented, for the first time, the use of direct infusion electrospray ionization low-resolution mass spectrometry associated with chemometric analysis (ESI-DIMS-PCA) for the detection of early stage cancer in mice. Ehrlich tumors were induced in Balb-C and Swiss mice, and blood was collected 1, 2, 3, 5, 7 and 10 days after tumor induction. Data from the mass spectra were analyzed via principal component analysis (PCA). Sample classifications were obtained within 3 days of tumor induction, which reflects a precocious time for cancer detection. ESI-DIMS-PCA was also used to detect cancer in groups of Swiss mice inoculated with sarcoma 180. Sample classifications were obtained 3 days after tumor induction, which indicates ESI-DIMS-PCA can be used to detect distinct neoplasms. Loading plot analysis demonstrated that the ions differentiating between the experimental and control groups are lysophosphatidylcholines and phosphatidylcholines. Partial least-squares analysis demonstrated that ESI-DIMS-PCA is capable of determining unknown samples in different stages of cancer development. ESI-DIMS with chemometric analysis is a promising technique for diagnosing cancer in the early stages without the need for invasive procedures.