Dataset Information

Chromatin Modification Abnormalities by CHD7 and KMT2C Loss Promote Medulloblastoma Progression [scMultiome]

ABSTRACT: Medulloblastoma, a common malignant pediatric brain tumor that typically originating from the cerebellum, is characterized by mutations in chromatin modifiers, highlighting the significance of epigenomic abnormalities in their progression. To prove this significance, the development and use of animal models that closely recapitulate the disease have been highly effective. However, due to substantial time and cost limitations of developing genetically engineered mouse models, a complete understanding of the oncogenic potential of chromatin modifiers’ mutations found in human medulloblastomas is still elusive. In this study, we address this by CRISPR-mediated gene editing platform to knock out chromatin modifiers mutated human in SHH-subgroup medulloblastoma as well as the Ptch1 gene in cerebellar granule neuron progenitors. We functionally screened molecules involved tumor formation, identifying CHD7 and KMT2C as tumor suppressor genes. Multi-layered omics analysis revealed that these molecules epigenetically regulate the expression of Neurod1 that encodes a transcription factor crucial for neuronal differentiation, through histone H3 modification. Mutations impairing these factors suppress Neurod1, accelerating tumor growth. Conversely, forced expression of Neurod1 inhibits proliferation and promotes differentiation, underscoring its role as a key regulator in medulloblastoma aggressiveness. These findings not only demonstrate converging epigenomic abnormalities in SHH-subgroup medulloblastoma but also hold significant potential for evaluating epigenetic drugs targeting medulloblastoma, advancing the development of novel treatments.

ORGANISM(S): Mus musculus

PROVIDER: GSE263361 | GEO | 2025/03/30

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Project description:Deregulated developmental processes in the cerebellum cause medulloblastoma, the most common malignant tumor of the central nervous system. About 20-30% of cases are caused by mutations increasing the activity of the Sonic hedgehog (Shh) pathway, a critical mitogen in cerebellar development. The proto-oncogene Smoothened is a key transducer of the Shh pathway. Activating mutations in Smoothened that lead to constitutive activity of the Shh pathway have been identified in human medulloblastoma. To understand the molecular and cellular effects of Smoothened variants in normal development and medulloblastoma genesis, we generated the SmoA2 transgenic mouse model which expresses the transgene exclusively in granule neuron precursors. In this study, we demonstrate how two point mutations in a single molecule can produce starkly different phenotypes as seen in comparison to our previous model, ND2:SmoA1. The SmoA2 mice have severe aberrations in cerebellar development whereas the SmoA1 mice are largely normal during development. Medulloblastomas in the SmoA2 mice develop in the dysplastic cerebellar milieu. Intriguingly, despite disruptions in the stereotypic organization of the cerebellum, the SmoA2 mice do not exhibit any overt abnormalities in motor coordination. The differences in the global transcriptional profiles downstream of SmoA1 and SmoA2 further demonstrate the distinctiveness of the two oncogenic Smoothened mutations. The SmoA2 model serves as a unique spatiotemporal tool to investigate the functional significance of the reiterative cerebellar circuitry as well as to further understand Shh pathway mechanics in cerebellar development and oncogenesis. We previously generated a SmoA1 transgenic mouse medulloblastoma model, which expresses the SmoA1 transgene driven by the GNP-specific fragment of the promoter of ND2 transcription factor leading to constitutively active Shh signaling exclusively in the cerebellum. In this study, we characterize the ND2:SmoA2 transgenic mouse model with a similarly designed transgene expressing the SmoA2 mutation. To assess transcriptional changes downstream of SmoA1 and SmoA2, we evaluated global gene expression profiles of P5 SmoA1, SmoA2 and Wt age-matched cerebella. We chose this specific developmental stage because (1) the phenotypes of SmoA1 and SmoA2 are robust and distinct at P5; (2) at P5 GNPs undergo proliferation, migration and differentiation and therefore expression profiling could capture key differences in multiple processes.

Dataset Information

Chromatin Modification Abnormalities by CHD7 and KMT2C Loss Promote Medulloblastoma Progression [scMultiome]

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets