Project description:Cell state evolution underlies tumor development and response to therapy, but mechanisms specifying cancer cell states and intratumor heterogeneity are incompletely understood. Schwannomas are the most common tumors of the peripheral nervous system and are treated with surgery and ionizing radiation. Schwannomas can oscillate in size for many years after radiotherapy, suggesting treatment may reprogram schwannoma cells or the tumor microenvironment. Here we show epigenetic reprogramming shapes the cellular landscape of schwannomas. We find schwannomas are comprised of 2 methylation based molecular groups distinguished by reactivation of neural crest development pathways or misactivation of nerve injury mechanisms that specify cancer cell states and the architecture of the tumor immune microenvironment. Schwannoma molecular groups can arise independently, but ionizing radiation is sufficient for epigenetic reprogramming of neural crest to immune-enriched schwannoma by remodeling chromatin accessibility, gene expression, and metabolism to drive schwannoma cell state evolution and immune cell infiltration. To define functional genomic mechanisms underlying epigenetic reprograming of schwannomas, we develop a technique for simultaneous interrogation of chromatin accessibility and gene expression coupled with genetic and therapeutic perturbations in single-nuclei. Our results elucidate a framework for understanding epigenetic drivers of cancer evolution and establish a paradigm of epigenetic reprograming of cancer in response to radiotherapy.
Project description:Cell state evolution underlies tumor development and response to therapy1, but mechanisms specifying cancer cell states and intratumor heterogeneity are incompletely understood. Schwannomas are the most common tumors of the peripheral nervous system and are treated with surgery and ionizing radiation2–5. Schwannomas can oscillate in size for many years after radiotherapy6,7, suggesting treatment may reprogram schwannoma cells or the tumor microenvironment. Here we show epigenetic reprogramming shapes the cellular landscape of schwannomas. We find schwannomas are comprised of 2 molecular groups distinguished by reactivation of neural crest development pathways or misactivation of nerve injury mechanisms that specify cancer cell states and the architecture of the tumor immune microenvironment. Schwannoma molecular groups can arise independently, but ionizing radiation is sufficient for epigenetic reprogramming of neural crest to immune-enriched schwannoma by remodeling chromatin accessibility, gene expression, and metabolism to drive schwannoma cell state evolution and immune cell infiltration. To define functional genomic mechanisms underlying epigenetic reprograming of schwannomas, we develop a technique for simultaneous interrogation of chromatin accessibility and gene expression coupled with genetic and therapeutic perturbations in single-nuclei. Our results elucidate a framework for understanding epigenetic drivers of cancer evolution and establish a paradigm of epigenetic reprograming of cancer in response to radiotherapy.
Project description:Vestibular schwannoma (VS) is the most common benign tumor in the cerebellopontine angle and internal auditory canal. Illustrating the heterogeneous cellular components of VS could provide insights into its various growth patterns. Single-cell RNA sequencing (scRNA-seq) was used to profile transcriptomes from 7 VS samples and 2 great auricular nerves as normal control.
Project description:Tumor miRNA expression is related to the growth rate of sporadic vestibular schwannomas. Rapid tumor growth is associated with deregulation of several miRNAs, including up-regulation of miR-29abc, miR-19, miR-340-5p, miR-21 and miR-221 and down-regulation of miR-744 and let-7b. Gene ontologies affected by the deregulated miRNAs included neuron development and differentiation, gene silencing and negative regulation of various biological processes, including cellular and intracellular signalling and metabolism. We used microarray to determine the miRNA expresison in vestibular schwannoma their relation to the growth rate.
Project description:Loss of NF2 (merlin) has been suggested as a genetic cause of neurofibromatosis type 2 and malignant peripheral nerve sheath tumor (MPNST). Previously, we demonstrated that NF2 sustained TGF- receptor 2 (TR2) expression and reduction or loss of NF2 activated non-canonical TGF- signaling, which reduced RKIP expression via TR1 kinase activity. Here, we show that a selective RKIP inducer (novel chemical, Nf18001) inhibits tumor growth and promotes schwannoma cell differentiation into mature Schwann cells under NF2-deficient conditions. In addition, Nf18001 is not cytotoxic to cells expressing NF2 and is not disturb canonical TGF- signaling. Moreover, the novel chemical induces expression of SOX10, a marker of differentiated Schwann cells, and promotes nuclear export and degradation of SOX2, a stem cell factor. Treatment with Nf18001 inhibited tumor growth in an allograft model with mouse schwannoma cells. These results strongly suggest that selective RKIP inducers could be useful for the treatment of neurofibromatosis type 2 as well as NF2-deficient MPNST. To know the global effect of Nf18001, we performed the microarray with HEI-193.
Project description:In this study, we have utilized affinity purification with a synthetic biotin-ceramide and LC-MS/MS to identify potential ceramide-interacting proteins in D6P2T Schwannoma cells.
Project description:Hearing loss (HL) is the most common sensory disorder in the world population. One common cause of hearing loss is the presence of vestibular schwannoma (VS) a benign tumor of the VIII cranial nerve, arising from Schwann cells (SCs) transformation. In the last decade, an increasing incidence of VSs may be ascribed to the exposure to electromagnetic field (EMF), which may be considered a pathogenic cause of VS development and HL. In this paper, we explore the possible molecular mechanisms underlying the biologic changes of human SCs and/or their oncogenic transformation following EMF exposure. We investigated, by NGS technology RNA-Seq transcriptomic analysis, the genomic profile and the differential display of HL-related genes following chronic EMF. We found that cell proliferation in parallel with intracellular signaling and metabolic pathways, mostly related to translation and mitochondrial activity were modified by chronic EMF exposure. Importantly, the expression of some HL-related genes, such as NEFL, TPRN, OTOGL, GJB2 and REST appeared regulated chronic EMF.
Project description:Treatment of multiple intracranial schwannomas in patient with neurofibromatosis type 2 (NF2) is extremely unsatisfactory and innovative therapeutic approaches are urgently needed. The lack of clinically relevant NF2 models has severely hampered drug discovery in this rare disease. Here, we report for the first time the establishment and characterization of patient-derived xenograft (PDX) and cell line models of NF2-associated schwannoma, which retain the gene mutations and transcriptome profile, and recapitulate the morphological and histopathological features with the patient tumors, retain patient NF2 mutations, and maintain gene expression profiles resembling the patient tumor profiles with the preservation of multiple key signaling pathways commonly dysregulated in human schwannoma. Using expression profiling, we found that the PI3K/AKT/mTOR networks are elevated in NF2-associated vestibular schwannomas, as well as in PDX models.