Surface-Enhanced Laser Desorption/Ionization Mass Spectrometry for Biomarker Discovery in Cutaneous Melanoma

Background: Melanoma is an aggressive malignancy and its increasing incidence worldwide has boosted interest in biomarker discovery in blood to monitor melanoma development, therapy efficacy, and to find new therapy targets. Our study aimed to discover candidate protein biomarkers that could have a double role, differentiate between melanoma patients and controls and distinguish patients with good clinical outcomes from patients with unfavorable one. Method: Melanoma patients in stages I-IV were followed-up for 5 years in specialized dermatology centers in southern Romania, from the years 2007 to 2015. Blood samples were drawn at diagnosis and at the time when the clinical outcome could be scored by the clinician as unfavorable or good. In order to obtain the best peptidic pattern of plasma, samples were fractionated using ProteoMinerTM Bead library and after fractionation subjected to SELDI-TOF-MS (surface-enhanced laser desorption/ ionization (SELDI) technology used with time-of-flight (TOF) mass spectrometers) analysis. Results: Nine peaks (p-values <0.01) in the peptide (mass) range were found up-regulated in melanoma patients. We found 3 peaks whose apparent relative abundances decreased in > 80% of patients with good outcomes, which was consistent with reverting to a proteomic profile more similar to controls. Conclusion: Mass spectrometry analysis of plasma can provide validated markers in development and treatment of cutaneous melanoma.