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Updated: Aug 6, 2026
06:21
Multi-Gene Single Nucleotide Polymorphism Detection in Gastric Cancer Based on Ion Semiconductor Sequencing Platform
Published on: May 10, 2024
CircRAD23B-208aa Promotes Gastric Cancer Progression by Activating the Unfolded Protein Response through PDIA5
Yuli Chen1,2, Jiahao Guo1, Ziwei Li1
1Department of Oncology, Suzhou Cancer Center Core Laboratory, Oncology Laboratory of Medical Science and Technology Innovation Center, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou Municipal Hospital, Gusu School, Nanjing Medical University, Suzhou, Jiangsu Province, China.
Research (Washington, D.C.)
|July 23, 2026
Summary
A novel circular RNA, circRAD23B, promotes gastric cancer growth and metastasis by activating the unfolded protein response (UPR) pathway. Targeting this pathway offers a new therapeutic strategy for gastric cancer.
Area of Science:
- Oncology
- Molecular Biology
- Genetics
Background:
- Gastric cancer (GC) is a deadly disease with poor outcomes.
- Limited effective therapies exist for advanced GC.
- Circular RNAs (circRNAs) are emerging as key players in cancer biology.
Purpose of the Study:
- To identify novel molecular mechanisms driving GC progression.
- To investigate the role of circRNAs in GC pathogenesis.
- To explore potential therapeutic targets for GC.
Main Methods:
- Integrated RNA sequencing and ribosome nascent-chain complex sequencing.
- Analysis of circRNA expression in GC tissues.
- Functional studies in vitro and in vivo.
- Investigation of protein-protein interactions and post-translational modifications.
Main Results:
- Identified circRAD23B, a circRNA significantly upregulated in GC.
- circRAD23B expression correlates with advanced stage, metastasis, and poor survival.
- circRAD23B encodes a protein (circRAD23B-208aa) that promotes GC proliferation, invasion, and metastasis.
- circRAD23B-208aa activates the unfolded protein response (UPR) pathway by stabilizing PDIA5 and enhancing ATF6 signaling.
- This represents the first identified circRNA-encoded activator of the UPR pathway.
Conclusions:
- circRAD23B is a novel oncogenic driver in gastric cancer.
- The circRAD23B-208aa protein activates the UPR pathway through PDIA5 SUMOylation and ATF6 signaling.
- Targeting the SUMOylation-dependent PDIA5/ATF6 axis presents a promising therapeutic strategy for GC.
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