My laboratory at Massachusetts General Hospital (MGH) studies pediatric and adult brain tumors with single-cell and spatial genomic technologies. We leverage a systems biology approach to characterize and target the cellular states that drive gliomas. We pioneered and co-directed the first studies leveraging single-cell RNA-sequencing to decipher human gliomas, with important implications for disease classification and for our understanding of intra-tumor heterogeneity. Our efforts have offered new insights into cancer stem cell programs, lineages of cellular differentiation, and the interplay between neural development and genetics in IDH-mutant oligodendroglioma (Tirosh et al., Nature 2016; Spitzer et al, Cancer Cell, 2024), IDH-mutant astrocytoma (Venteicher et al., Science 2017), pediatric gliomas with histone H3 mutation (Filbin et al., Science 2018), IDH-wildtype glioblastoma (Patel et al, Science 2014; Neftel et al, Cell 2019; Chaligne et al, Nature Genetics 2021; Mangena et al, Cancer Discovery 2024; Nomura et al, Nature Genetics 2025; Spitzer et al, Nature Genetics 2025) and medulloblastoma (Hovestadt et al, Nature, 2019). Our studies are also characterizing and refining our understanding of the composition of the tumor micro-environment in gliomas (Mathewson et al, Cell 2021; Hara et al, Cancer Cell 2021) and of the spatial architecture of these tumors (Greenwald et al, Cell, 2024). Overall, my laboratory has dissected with great details the circuitries of cancer and immune cells in human brain tumors, offering novel insights into their biology and into vulnerabilities that could be leveraged for their management.  In addition to leading these efforts, my laboratory is deeply embedded into numerous collaborative projects within the DF/HCC neuro-oncology program (e.g. co-leader of the Harvard brain cancer SPORE).