Comprehensive MALDI mass spectrometry imaging of tumor regions post-neoadjuvant therapy

The spatial metabolic analysis of tumor tissues following neoadjuvant chemotherapy (NAC) is critical for understanding chemotherapy-induced metabolic changes. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) offers a powerful tool for revealing spatially resolved metabolic profiles within tissues. However, necrotic regions in post-NAC tissues are fragile, creating challenges for sample preparation and MALDI MSI analysis. In this study, we introduce an optimized workflow employing conductive tape to stabilize tissue samples during sectioning and MALDI MSI analysis, preserving necrotic areas while maintaining tissue integrity. Using this technique, we successfully mapped metabolic alterations across necrotic and viable regions of post-NAC tumor tissues, providing new insights into metabolic changes that occur after chemotherapy. Our findings establish MALDI MSI as a valuable tool for spatially resolved metabolomics in post-NAC tumor tissues, offering insights into chemotherapy-induced metabolic changes.