Fig. 5

Publication statistics of spatiotemporal metabolomic measurements in studying cancer-immunity. a, b, c Number of publications focused on caner-immunity (keywords: (((cancer immun*) OR tumor immun*) OR “tumor microenvironment”)) and different measurements, including omics (a), single-cell omics (b), and spatial omics (c), reported by PubMed. Blue curves show the total number of publications by adding the following keywords to search: transcriptom* (a), (((“single-cell transcriptom*”) OR “scRNA-seq”) OR “single-cell RNA-seq”) (b), and ((“spatial transcriptom*”) OR “spatial RNA-seq”) (c). Orange curves show the total number of publications by adding the following keywords to search: proteom* (a), (((“single-cell proteom*”) OR “mass cytometry”) OR “CyTOF”) (b), and ((“spatial proteom*”) (c). Red dashed curves show the total number of publications by adding the following keywords to search: metabolom* (a), (((“single-cell metabolom*”) OR “single-cell mass spectrom”) OR “single-cell MS”) (b), and ((“spatial metabolom*”) (c). d Timeline of the milestone single-cell-level metabolomic techniques. Techniques marked in red have been used to study cancer-immunity. CE, capillary electrophoresis; GCIB, gas cluster ion beam; MS, mass spectrometry; SEAM, spatial single nuclear metabolomics; SIMS, secondary ion mass spectrometry; SLMS, single-lysosome mass spectrometry