SOXC Enhances NGN2-Mediated Reprogramming of Glioblastoma Cells Into Neuron-Like Cells by Modulating RhoA and RAC1/CDC42 Pathway Activity

CNS Neurosci Ther. 2024 Oct;30(10):e70075. doi: 10.1111/cns.70075.

Abstract

Background: Glioblastoma represents the most frequently diagnosed malignant neoplasm within the central nervous system. Human glioblastoma cells can be phenotypically reprogrammed into neuron-like cells through the forced expression of NEUROG2 and SOXC factors. NEUROG2 serves as a pioneer factor, establishing an initial framework for this transformation. However, the specific role of SOXC factors has not been fully elucidated.

Methods: In this study, we used ChIP-seq to determine the potential target gene of NGN2. RNA-seq has been used to evaluate the transcriptional change during NGN2-SOX11-mediated neuron reprogramming. Immunofluorescence was used to determine the neuron reprogramming efficacy and cell proliferation ability. ChIP-qPCR, Co-IP, and Western Blot were performed to investigate the mechanism.

Results: Our findings reveal that SOXC factors, in contrast to their previously identified function as transcriptional activators, act as transcriptional repressors. They achieve this by recruiting TRIM28 to suppress the expression of ECT2, a RhoGEF. This suppression results in the differential regulation of RhoA, RAC1, and CDC42 activities throughout the reprogramming process. We further establish that small molecules targeting RhoA and its effectors can substitute for SOXC factors in facilitating the neuronal reprogramming of glioblastoma cells.

Conclusion: These results underscore the pivotal role of SOXC factors' transcriptional repression and illuminate one of their specific downstream targets.

Keywords: ECT2; NGN2; RAC1/CDC42; RhoA; SOX4/11; glioblastoma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Basic Helix-Loop-Helix Transcription Factors* / genetics
  • Basic Helix-Loop-Helix Transcription Factors* / metabolism
  • Brain Neoplasms / genetics
  • Brain Neoplasms / metabolism
  • Brain Neoplasms / pathology
  • Cell Line, Tumor
  • Cellular Reprogramming* / physiology
  • Glioblastoma* / genetics
  • Glioblastoma* / metabolism
  • Glioblastoma* / pathology
  • Humans
  • Nerve Tissue Proteins* / genetics
  • Nerve Tissue Proteins* / metabolism
  • Neurons* / metabolism
  • SOXC Transcription Factors* / genetics
  • SOXC Transcription Factors* / metabolism
  • Signal Transduction* / physiology
  • cdc42 GTP-Binding Protein* / genetics
  • cdc42 GTP-Binding Protein* / metabolism
  • rac1 GTP-Binding Protein* / genetics
  • rac1 GTP-Binding Protein* / metabolism
  • rhoA GTP-Binding Protein* / genetics
  • rhoA GTP-Binding Protein* / metabolism

Substances

  • rac1 GTP-Binding Protein
  • rhoA GTP-Binding Protein
  • Nerve Tissue Proteins
  • cdc42 GTP-Binding Protein
  • Basic Helix-Loop-Helix Transcription Factors
  • RAC1 protein, human
  • RHOA protein, human
  • NEUROG2 protein, human
  • SOXC Transcription Factors
  • CDC42 protein, human
  • SOX11 protein, human