MALDI-MSI analysis of cancer drugs: Significance, advances, and applications

Abstract Because of the heterogeneity and complexity of tumor structure, cancer drugs often cannot effectively reach the tumor, which is one of the reasons for drug resistance and treatment failure. Therefore, the distribution and the metabolism of cancer drugs within the tumor and the body are essential concerns during drug development and cancer therapy. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) has been demonstrated to be a powerful label-free technique to characterize the spatial biodistributions of cancer drugs and their metabolites, facilitating the delivery of safe and effective drugs to the market and eventually benefiting cancer patients. In this review, recent advances are thoroughly reviewed regarding the MALDI-MSI analysis of cancer drugs in preclinical and clinical settings, including technical aspects and practical applications. In conclusion, the significance and future directions of MALDI-MSI in cancer drug research and development are summarized.