Abrogation of Rb Tumor Suppression Initiates GBM in Differentiated Astrocytes by Driving a Progenitor Cell Program
Amit S Adhikari1, Teresa Sullivan1, Rhishikesh Bargaje2
1Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, United States.
Frontiers in Oncology
|July 11, 2022
Summary
Differentiated astrocytes can develop into glioblastoma (GBM) when the RB tumor suppressor pathway is disrupted. This disruption triggers a progenitor-like state, leading to tumor formation and progression.
Area of Science:
- Neuro-oncology
- Cancer Biology
- Developmental Neuroscience
Background:
- Glioblastoma (GBM) is a fatal brain cancer with limited treatment options.
- The early cellular origins of GBM are not well understood.
- GBM is thought to originate in neural progenitor or stem cells.
Purpose of the Study:
- To investigate the role of differentiated astrocytes in GBM development.
- To determine if perturbing the RB pathway can initiate GBM in astrocytes.
- To understand the cellular mechanisms underlying GBM initiation.
Main Methods:
- Inactivation of the Rb tumor suppressor gene in cortical astrocytes.
- In vitro and in vivo experimental models.
- Analysis of astrocyte proliferation, differentiation markers, and self-renewal capacity.
Main Results:
- Rb inactivation induced rapid astrocyte proliferation and progenitor marker expression.
- Inactivated astrocytes formed self-renewing neurospheres.
- This progenitor-like phenotype was sufficient to initiate grade II astrocytomas that progressed to GBM.
Conclusions:
- Differentiated astrocytes are susceptible to GBM initiation upon RB pathway perturbation.
- RB pathway inactivation drives astrocytes to a progenitor-like state, enabling GBM development.
- Cellular susceptibility to GBM initiation is dependent on the specific molecular driver.
