UPLC‑MS/MS‑based metabolomic characterization and comparison of pancreatic adenocarcinoma tissues using...

The purpose of the present study was to compare metabolites from formalin‑fixed and paraffin‑embedded (FFPE) pancreatic tissue blocks with those identified in optimal cutting temperature (OCT)‑embedded pancreatic tissue blocks. Thus, ultra‑performance liquid chromatograph‑mass spectrometry/mass spectrometry‑based metabolic profiling was performed in paired frozen (n=13) and FFPE (n=13) human pancreatic adenocarcinoma tissue samples, in addition to their benign counterparts. A total of 206 metabolites were identified in both OCT‑embedded and FFPE tissue samples. The method feasibility was confirmed through reproducibility and a consistency assessment. Partial least‑squares discriminant analysis and heatmap analysis reliably distinguished tumor and normal tissue phenotypes. The expression of 10 compounds, including N‑acetylaspartate and creatinine, was significantly different in both OCT‑embedded and FFPE tumor samples. These ten compounds may be viable candidate biomarkers of malignant pancreatic tissues. The super‑categories to which they belonged exhibited no significant differences between FFPE and OCT‑embedded samples. Furthermore, purine, arginine and proline, and pyrimidine metabolism used a shared pathway found in both OCT‑embedded and FFPE tissue samples. These results supported the notion that metabolomic data acquired from FFPE pancreatic cancer specimens are reliable for use in retrospective and clinical studies.