Summary: Researchers have identified the tRNA-binding protein TRNAU1AP as a critical driver of glioblastoma (GBM) stem cell survival and tumor progression.
A multidisciplinary team showed that elevated TRNAU1AP expression in tumors correlates with poorer clinical outcomes for glioblastoma patients. TRNAU1AP organizes into liquid-like intracellular clusters that selectively enhance the translation of selenoproteins. These selenoproteins, which incorporate selenium, help cancer stem cells withstand oxidative stress and resist therapies.
The study further reveals that the RNA-binding protein IGF2BP3 acts as an N6-methyladenosine (m6A) reader that binds m6A-modified TRNAU1AP mRNA, shielding it from degradation and maintaining high TRNAU1AP protein levels. Disrupting the IGF2BP3–TRNAU1AP axis therefore represents a promising strategy to weaken glioblastoma stem cell defenses and improve therapeutic response.
Key Facts
- TRNAU1AP and patient survival: Analyses of clinical tumor samples and public multi-omic datasets demonstrate that high TRNAU1AP expression is associated with significantly reduced overall survival in glioblastoma patients.
- Driver of selenoprotein production: TRNAU1AP forms phase-separated intracellular clusters that promote efficient translation of a subset of selenoproteins. Those selenoproteins use selenium to protect glioblastoma stem cells from oxidative damage and treatment effects.
- Regulation by IGF2BP3 and m6A: IGF2BP3 recognizes m6A chemical marks on TRNAU1AP mRNA, binds those modified transcripts, and increases their stability, resulting in persistent TRNAU1AP protein overexpression.
- Essential for cancer stem cells: Glioblastoma stem cells depend on the IGF2BP3–TRNAU1AP pathway to retain self-renewal, sustain tumor growth, and resist standard treatments.
- Therapeutic opportunity: Lead investigator Suyun Huang emphasizes the potential to develop small-molecule IGF2BP3 inhibitors that penetrate the central nervous system and block IGF2BP3–RNA interactions to destabilize tumor-supporting transcripts.
Source: Virginia Commonwealth University
New research published in Neuro-Oncology highlights discoveries that could influence the future of glioblastoma therapy and patient outcomes.
A team from Virginia Commonwealth University, VCU Massey Comprehensive Cancer Center and the University of Texas MD Anderson Cancer Center identified TRNAU1AP as a key protein that enables glioblastoma cells—particularly glioblastoma stem cells—to survive, grow, and resist treatment. Their work outlines a mechanistic pathway that may be targeted to sensitize these tumors to therapy.
“We believe this pathway could be targeted to kill this tumor,” said Suyun Huang, Ph.D., lead author, Cancer Biology research program member at Massey, and professor in the Department of Cellular, Molecular, and Genetic Medicine at the VCU School of Medicine. “If we can inhibit these proteins, it may open new therapeutic avenues against this deadly disease.”
About glioblastoma (GBM)
- The most aggressive and common malignant primary brain tumor.
- Extremely difficult to treat because a subpopulation of cancer stem cells sustain tumor growth and drive therapy resistance.
- Median survival remains limited; despite advances, typical survival after diagnosis is on the order of months to a little over a year in many cases.
- Relies on selenoproteins—a group of proteins important to neural function and antioxidant defense—for progression and survival.
The research findings
By integrating tumor tissue analysis and public datasets, the investigators showed that TRNAU1AP supports proliferation, stemness, and tumorigenesis in glioblastoma stem cells (GSCs). Patients whose tumors expressed higher TRNAU1AP levels had worse survival outcomes. Mechanistic studies revealed that TRNAU1AP condenses with the translation factor EEFSEC into phase-separated complexes that increase EEFSEC interaction with selenocysteine tRNA (sec-tRNAsec), thereby promoting translation of several key selenoproteins. Those selenoproteins act as effectors that enable the oncogenic functions of TRNAU1AP.
The team also found that IGF2BP3, a prominent m6A reader in GBM, binds m6A-modified TRNAU1AP mRNA transcripts and protects them from degradation. This m6A-dependent stabilization of TRNAU1AP mRNA leads to sustained selenoprotein production and enhanced GSC stemness and tumorigenicity. Together, these results define an IGF2BP3–TRNAU1AP–selenoprotein axis that sustains gliomagenesis.
What’s next?
Huang and colleagues plan to pursue small-molecule inhibitors of IGF2BP3 that can cross the blood–brain barrier. The objective is to disrupt IGF2BP3’s interaction with m6A-modified RNAs, destabilize TRNAU1AP transcripts, reduce protective selenoprotein levels, and render glioblastoma stem cells more susceptible to existing therapies.
Collaborators
- Additional VCU collaborators: Xiaowei Zhang, M.D.; Li Li, Ph.D.; Linlin Li, Ph.D.; Shijun Yu, M.D., Ph.D.; Taohui Ouyang, M.D.; Xiao Han, Ph.D.; Richard I. Joh, Ph.D.; and Huizhi Wang, Ph.D.
- Scientists from MD Anderson Cancer Center.
This research was funded by
- Paul M. Corman, MD Chair in Cancer Research Endowment Fund
- National Center for Advancing Translational Sciences
- CCTR Endowment Fund of Virginia Commonwealth University
Key Questions Answered:
A: Glioblastoma contains a specialized population of cancer stem cells that self-renew, sustain tumor growth, and resist conventional radiation and chemotherapy. These cells exploit protective mechanisms—such as increased selenoprotein synthesis—to survive oxidative stress and therapeutic damage.
A: IGF2BP3 functions as an m6A reader that recognizes N6-methyladenosine marks on TRNAU1AP mRNA. By binding these modified transcripts, IGF2BP3 prevents their degradation, increasing mRNA stability and enabling continued translation of TRNAU1AP protein.
A: Designing brain-penetrant small molecules that block IGF2BP3–RNA binding could destabilize TRNAU1AP mRNA, reduce protective selenoprotein levels, and sensitize glioblastoma stem cells to existing therapies, potentially improving treatment outcomes.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- The journal paper was reviewed in full.
- Additional context was provided by staff editors.
About this brain cancer research news
Author: Blake Belden
Source: Virginia Commonwealth University
Contact: Blake Belden – Virginia Commonwealth University
Image: Image credited to Neuroscience News
Original Research: Open access. “Phase separation of TRNAU1AP protein sustains selenoprotein translation and promotes glioblastoma tumorigenesis” by Xiaowei Zhang, Li Li, Linlin Li, Shijun Yu, Taohui Ouyang, Xiao Han, Richard I. Joh, Yiwen Chen, Huizhi Wang, Suyun Huang. Neuro-Oncology. DOI: 10.1093/neuonc/noag097
Abstract
Phase separation of TRNAU1AP protein sustains selenoprotein translation and promotes glioblastoma tumorigenesis
Background
Glioblastoma depends on selenoproteins, but the mechanisms that dysregulate their expression are not fully understood. The tRNA-binding protein TRNAU1AP has been incompletely characterized, and its role in tumorigenesis in vivo remained unclear. IGF2BP3 is one of the most dysregulated m6A readers in GBM, yet how it promotes glioblastoma stem cell (GSC) self-renewal had not been defined.
Methods
TRNAU1AP expression in human GBM samples and public datasets was assessed by Western blotting, immunohistochemistry, and gene expression analyses. The functional roles of TRNAU1AP in GSCs were tested using gain- and loss-of-function experiments measuring proliferation, self-renewal, and tumorigenicity. Proteomics, spatial transcriptomics, RNA immunoprecipitation, and polysome profiling investigated how TRNAU1AP regulates selenoprotein synthesis. RNA immunoprecipitation and phase-separation assays characterized the TRNAU1AP–EEFSEC interaction. Multiomics and RNA stability studies probed IGF2BP3-dependent control of TRNAU1AP expression.
Results
TRNAU1AP is required for GSC proliferation, stemness, and tumorigenesis and is linked to poor patient survival. TRNAU1AP interacts with EEFSEC to form a phase-separated complex that strengthens EEFSEC binding to sec-tRNAsec, promoting translation of multiple selenoproteins. These selenoproteins act as downstream effectors of TRNAU1AP’s oncogenic activity. IGF2BP3 upregulates TRNAU1AP via m6A-dependent transcript stabilization, driving elevated selenoprotein synthesis and reinforcing GSC stemness and tumorigenic potential.
Conclusion
The study identifies novel oncogenic roles for TRNAU1AP and describes IGF2BP3–TRNAU1AP coupling as a key mechanism supporting selenoprotein synthesis and gliomagenesis. These insights advance understanding of RNA-binding proteins in cancer biology and point to potential therapeutic targets in glioblastoma.