Analysis of urinary nucleosides as potential cancer markers determined using LC-MS technique

Nucleosides, the RNA metabolites, are well known as potential markers in various types of cancer. They are mainly detected in urine wherein their concentrations were found elevated in cancer patients. In order to determine the nucleosides' profile in urine with satisfactory sensitivity and accuracy, advanced analytical techniques should be applied involving mass spectrometry detection. In this work we overviewed actual possibilities in targeted and untargeted metabolomics studies of nucleosides and their analogues (cis-diol metabolites) using high performance liquid chromatography hyphenated with mass spectrometry detection. We focused on challenges and drawbacks using different types of ion sources and analyzers. The nucleosides' fragmentation patterns were also compared for the sake of their identification in biological samples. As applied analytical techniques allow for the metabolites' determination, statistical approach essential for evaluation of nucleosides as cancer markers was also reviewed.