Project description:Somatic chromosomal deletions are prevalent in cancer, yet their effects are poorly understood. The most prominent homozygous deletions affect chromosome 9p21.3 and eliminate the CDKN2A/B tumor suppressor genes, thus disabling a cell intrinsic barrier to tumorigenesis. However, half of 9p21.3 deletions encompass a cluster of 16 type I interferons (IFNs) whose co-deletion remains unexplored. To functionally dissect 9p21.3 and other genomic deletions, we developed MACHETE (Molecular Alteration of Chromosomes with Engineered Tandem Elements), a genome engineering strategy that enables flexible modeling of megabase-sized deletions. Applying MACHETE to a syngeneic mouse model of pancreatic cancer, we show that concomitant loss of the IFN cluster with Cdkn2a/b enhanced immune evasion, metastasis, and immunotherapy resistance compared to Cdkn2a/b deletions alone. Mechanistically, IFN co-deletion disrupted type I IFN signaling in the tumor microenvironment, leading to marked changes in infiltrating immune cells and escape from CD8+ T cell surveillance, effects largely driven by the poorly understood interferon epsilon (Ifne). These results reveal how IFN-encompassing 9p21.3 deletions disable cell intrinsic and extrinsic tumor suppression, thereby providing a pervasive route for immune evasion, metastasis, and immunotherapy resistance. Our study provides a framework for interrogating large deletion events in cancer and beyond.
Project description:Somatic chromosomal deletions are prevalent in cancer, yet their effects are poorly understood. The most prominent homozygous deletions affect chromosome 9p21.3 and eliminate the CDKN2A/B tumor suppressor genes, thus disabling a cell intrinsic barrier to tumorigenesis. However, half of 9p21.3 deletions encompass a cluster of 16 type I interferons (IFNs) whose co-deletion remains unexplored. To functionally dissect 9p21.3 and other genomic deletions, we developed MACHETE (Molecular Alteration of Chromosomes with Engineered Tandem Elements), a genome engineering strategy that enables flexible modeling of megabase-sized deletions. Applying MACHETE to a syngeneic mouse model of pancreatic cancer, we show that concomitant loss of the IFN cluster with Cdkn2a/b enhanced immune evasion, metastasis, and immunotherapy resistance compared to Cdkn2a/b deletions alone. Mechanistically, IFN co-deletion disrupted type I IFN signaling in the tumor microenvironment, leading to marked changes in infiltrating immune cells and escape from CD8+ T cell surveillance, effects largely driven by the poorly understood interferon epsilon (Ifne). These results reveal how IFN-encompassing 9p21.3 deletions disable cell intrinsic and extrinsic tumor suppression, thereby providing a pervasive route for immune evasion, metastasis, and immunotherapy resistance. Our study provides a framework for interrogating large deletion events in cancer and beyond.
Project description:single cell RNASEQ files for Mullighan BiTE RNASEQ3 paper titled "Tumor intrinsic and extrinsic mechanisms of response and resistance to blinatumomab in relapsed/refractory acute lymphoblastic leukemia"
Project description:Correct neural progenitor fate determination requires the coordination of extrinsic fate determinant signals with intrinsic responses. Post-translational modifications dynamically alter protein function and so are ideally situated to regulate development. Here we show that the deubiquitylaying enzyme, Usp9x modulates both intrinsic and extrinsic regulators of mouse neural progenitors. Nestin-cre mediated deletion of Usp9x from neural progenitors results in a transient disruption of cell adhesion and apical-basal polarity as well as the premature differentiation of intermediate neural progenitors. Ablation of Usp9x also significantly increased β-catenin protein levels, especially S33/S37/T41 phospho-β-catenin, and Wnt signalling. Usp9x was found to be part of the β-catenin destruction complex and loss of Usp9x affects destruction complex composition. Notch signalling was also increased in Usp9x ablated neural progenitors, coinciding with decreased Itch and Numb, and increased Notch intracellular domain protein levels. Usp9x co-localized and immunopreciptiated with Numb from neural progenitors suggesting it is required for Numb stabilisation. These data suggest Usp9x plays a role in coordinating intrinsic responses to extrinsic signals during neural development.
Project description:Dissection of tumor-intrinsic and tumor-extrinsic features of MIT/TFE translocation renal cell carcinoma via single-nucleus RNA sequencing
Project description:WXS files for Mullighan BiTE WXS paper titled "Tumor intrinsic and extrinsic mechanisms of response and resistance to blinatumomab in relapsed/refractory acute lymphoblastic leukemia"
