Profiling of Serum Metabolites Using MALDI-TOF and Triple-TOF Mass Spectrometry to Develop a Screen for Ovarian Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: We sought to develop a matrix assisted laser desorption ionization-time of flight (MALDI-TOF)-based, ovarian cancer (OVC), low-mass-ion discriminant equation (LOME) and to evaluate a possible supportive role for triple-TOF mass analysis in identifying metabolic biomarkers. MATERIALS AND METHODS: A total of 114 serum samples from patients with OVC and benign ovarian tumors were subjected to MALDI-TOF analysis and a total of 137 serum samples from healthy female individuals and patients with OVC, colorectal cancer, hepatobiliary cancer, and pancreatic cancer were subjected to triple-TOF analysis. An OVC LOME was constructed by reference to the peak intensity ratios of discriminatory low-mass ion (LMI) pairs. Triple-TOF analysiswas used to select and identify metabolic biomarkers for OVC screening. RESULTS: Three OVC LOMEs were finally constructed using discriminatory LMI pairs (137.1690 and 84.4119 m/z; 496.5022 and 709.7642 m/z; and 524.5614 and 709.7642 m/z); all afforded accuracies of > 90%. The LMIs at 496.5022 m/z and 524.5614 m/z were those of lysophosphatidylcholine (LPC) 16:0 and LPC 18:0. Triple-TOF analysis selected seven discriminative LMIs; each LMI had a specificity > 90%. Of the seven LMIs, fourwith a 137.0455 m/z ion atretention times of 2.04-3.14 minuteswere upregulated in sera from OVC patients; the ion was identified as that derived from hypoxanthine. CONCLUSION: MALDI-TOF–based OVC LOMEs combined with triple-TOF–based OVC metabolic biomarkers allow reliable OVC screening; the techniques are mutually complementary both quantitatively and qualitatively.

Identification of Hypoxanthine and Phosphoenolpyruvic Acid as Serum Markers of Chemoradiotherapy Response in Locally Advanced Rectal Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Patients show variable responses to chemoradiotherapy (CRT), which is generally administered before surgery for locally advanced rectal cancer (LARC). The aim of this study was to identify molecular markers predictive of CRT responses by analysis of low-mass ions (LMIs) in serum of LARC patients. MATERIALS AND METHODS: LMIs ( 16.0 muM showed significant association with ypStage 0-1 or TRG 4-3 than ypStage 3-4 (p=0.009) or TRG 1 (p=0.024), respectively. In contrast, a significantly lower concentration of PEP was observed in TRG 4-3 compared with TRG 2-1 (p=0.012). CONCLUSION: Findings of this study demonstrated that serum concentrations of HX and PEP, identified using LMI profiling, may be useful for predicting the CRT response of LARC patients before treatment.