Metabolic profiling on formalin-fixed paraffin-embedded breast cancer tissue using desorption electrospray ionization mass spectrometry imaging

Abstract: A broad range of diseases are identified based on histology. Today, most pathological tissue samples are stored as formalin-fixed paraffin embedded (FFPE) tissue blocks, which is the gold standard for histopathological analysis. Mass spectrometry imaging (MSI) is a powerful tool that enables us to investigate the regional distribution of a variety of molecules in biological samples. Desorption electrospray ionization mass spectrometry imaging (DESI-MSI) is particularly suited to investigate the spatial distribution of metabolites. Metabolite measurements are growing in importance as altered metabolism is a hallmark of many diseases, such as cancer. Currently, fresh frozen (FF) samples are preferred over FFPE samples in tissue based MSI studies. This is primarily due to the concern that metabolites will be lost during fixation and chemical processing. My results indicate that we are able to detect metabolites in FFPE samples.