Similar Datasets
Project description:Lineage plasticity and stemness have been invoked as causes of therapy resistance in cancer, because these flexible states allow cancer cells to dedifferentiate and alter their dependencies. We investigated such resistance mechanisms in relapsed/refractory early T-cell progenitor acute lymphoblastic leukemia (ETP-ALL) carrying activating NOTCH1 mutations via full-length single-cell RNA sequencing (scRNA-seq) of malignant and microenvironmental cells. We identified 2 highly distinct stem-like states that critically differed with regard to cell cycle and oncogenic signaling. Fast-cycling stem-like leukemia cells demonstrated Notch activation and were effectively eliminated in patients by Notch inhibition, whereas slow-cycling stem-like cells were Notch independent and rather relied on PI3K signaling, likely explaining the poor efficacy of Notch inhibition in this disease. Remarkably, we found that both stem-like states could differentiate into a more mature leukemia state with prominent immunomodulatory functions, including high expression of the LGALS9 checkpoint molecule. These cells promoted an immunosuppressive leukemia ecosystem with clonal accumulation of dysfunctional CD8+ T cells that expressed HAVCR2, the cognate receptor for LGALS9. Our study identified complex interactions between signaling programs, cellular plasticity, and immune programs that characterize ETP-ALL, illustrating the multidimensionality of tumor heterogeneity. In this scenario, combination therapies targeting diverse oncogenic states and the immune ecosystem seem most promising to successfully eliminate tumor cells that escape treatment through coexisting transcriptional programs.
| S-EPMC8109012 | biostudies-literature
Project description:Lineage plasticity and stemness have been invoked as the cause of therapy resistance in cancer, as these flexible states allow cancer cells to de-differentiate and alter their dependencies. We investigated such resistance mechanisms in relapsed / refractory early T-cell progenitor acute lymphoblastic leukemia carrying activating NOTCH1 mutations, by full-length single cell RNA sequencing of malignant and microenvironmental cells. We identified two highly distinct stem-like states that critically differ in their cell-cycle and oncogenic signaling. Fast-cycling stem-like leukemia cells demonstrate Notch activation and are effectively eliminated in patients by Notch inhibition, while slow cycling stem-like cells are Notch-independent but rather rely on PI3K signaling, likely explaining the poor efficacy of Notch inhibition in this disease. Remarkably, we find that both stem-like states can differentiate into a more mature leukemia state with prominent immune-modulatory functions, including high expression of the LGALS9 checkpoint molecule. These cells promote an immunosuppressive leukemia ecosystem with clonal accumulation of dysfunctional CD8+ T cells that express HAVCR2, the cognate receptor for LGALS9. Our study identifies complex interactions between signaling programs, cellular plasticity and immune programs that characterize T-ALL and illustrates the multi-dimensionality of tumor heterogeneity. In this scenario, combination therapies targeting diverse oncogenic states and the immune ecosystem appear most promising to successfully eliminate tumor cells that escape treatment through co-existing transcriptional programs.
2021-01-01 | GSE161895 | GEO
Project description:Lineage plasticity and stemness have been invoked as the cause of therapy resistance in cancer, as these flexible states allow cancer cells to de-differentiate and alter their dependencies. We investigated such resistance mechanisms in relapsed / refractory early T-cell progenitor acute lymphoblastic leukemia carrying activating NOTCH1 mutations, by full-length single cell RNA sequencing of malignant and microenvironmental cells. We identified two highly distinct stem-like states that critically differ in their cell-cycle and oncogenic signaling. Fast-cycling stem-like leukemia cells demonstrate Notch activation and are effectively eliminated in patients by Notch inhibition, while slow cycling stem-like cells are Notch-independent but rather rely on PI3K signaling, likely explaining the poor efficacy of Notch inhibition in this disease. Remarkably, we find that both stem-like states can differentiate into a more mature leukemia state with prominent immune-modulatory functions, including high expression of the LGALS9 checkpoint molecule. These cells promote an immunosuppressive leukemia ecosystem with clonal accumulation of dysfunctional CD8+ T cells that express HAVCR2, the cognate receptor for LGALS9. Our study identifies complex interactions between signaling programs, cellular plasticity and immune programs that characterize T-ALL and illustrates the multi-dimensionality of tumor heterogeneity. In this scenario, combination therapies targeting diverse oncogenic states and the immune ecosystem appear most promising to successfully eliminate tumor cells that escape treatment through co-existing transcriptional programs.
2021-01-01 | GSE161896 | GEO
Project description:Single cell RNA-seq reveals developmental plasticity with coexisting oncogenic states and immune evasion programs in ETP-ALL
| PRJNA679811 | ENA
Project description:Single cell RNA-seq reveals developmental plasticity with coexisting oncogenic states and immune evasion programs in ETP-ALL [PDX_ETPs_scRNA-seq]
| PRJNA679819 | ENA
Project description:Single cell RNA-seq reveals developmental plasticity with coexisting oncogenic states and immune evasion programs in ETP-ALL [Patients_TALLs_scRNA-seq]
| PRJNA679818 | ENA
Project description:Gliomas with histone H3 lysine27-to-methionine mutations (H3K27M-glioma) arise primarily in the midline of the central nervous system of young children, suggesting a cooperation between genetics and cellular context in tumorigenesis. Although the genetics of H3K27M-glioma are well characterized, their cellular architecture remains uncharted. We performed single-cell RNA sequencing in 3321 cells from six primary H3K27M-glioma and matched models. We found that H3K27M-glioma primarily contain cells that resemble oligodendrocyte precursor cells (OPC-like), whereas more differentiated malignant cells are a minority. OPC-like cells exhibit greater proliferation and tumor-propagating potential than their more differentiated counterparts and are at least in part sustained by PDGFRA signaling. Our study characterizes oncogenic and developmental programs in H3K27M-glioma at single-cell resolution and across genetic subclones, suggesting potential therapeutic targets in this disease.
| S-EPMC5949869 | biostudies-literature
Project description:Oncogenes only transform cells under certain cellular contexts, a phenomenon called oncogenic competence. Using a combination of a human pluripotent stem cell–derived cancer model along with zebrafish transgenesis, we demonstrate that the transforming ability of BRAFV600E along with additional mutations depends on the intrinsic transcriptional program present in the cell of origin. In both systems, melanocytes are less responsive to mutations, whereas both neural crest and melanoblast populations are readily transformed. Profiling reveals that progenitors have higher expression of chromatin-modifying enzymes such as ATAD2, a melanoma competence factor that forms a complex with SOX10 and allows for expression of downstream oncogenic and neural crest programs. These data suggest that oncogenic competence is mediated by regulation of developmental chromatin factors, which then allow for proper response to those oncogenes.
| S-EPMC9440978 | biostudies-literature
Project description:Epithelial-mesenchymal transition (EMT) is a fundamental process that occurs during embryogenesis and tissue repair. However, EMT can be hijacked by malignant cells, where it may promote immune evasion and metastasis. Classically considered a dichotomous transition, EMT in cancer has recently been considered a plastic process whereby malignant cells display and interconvert among hybrid epithelial/mesenchymal (E/M) states. Epithelial-mesenchymal plasticity (EMP) and associated hybrid E/M states are divergent from classical EMT, with unique immunomodulatory effects. Here, we review recent insights into the EMP-immune cross-talk, highlighting possible mechanisms of immune evasion conferred by hybrid E/M states and roles of immune cells in EMP.
| S-EPMC9256788 | biostudies-literature
Project description:PML-RARA and AML1-ETO are important oncogenic fusion proteins that play a central role in transformation to acute myeloid leukemia (AML). Whether these fusion proteins render the tumor cells with immune evasion properties is unknown. Here we show that both oncogenic proteins specifically downregulate the expression of CD48, a ligand of the natural killer (NK) cell activating receptor 2B4, thereby leading to decreased killing by NK cells. We demonstrate that this process is histone deacetylase (HDAC)-dependent, that it is mediated through the downregulation of CD48 messenger RNA, and that treatment with HDAC inhibitors (HDACi) restores the expression of CD48. Furthermore, by using chromatin immunoprecepitation (ChIP) experiments, we show that AML1-ETO directly interacts with CD48. Finally, we show that AML patients who are carrying these specific translocations have low expression of CD48.
| S-EPMC3981677 | biostudies-literature