p53 activates circASCC3 to repress R-loops and enhance resistance to chemotherapy
The tumor suppressor p53 can trigger tumor resistance to chemotherapy by facilitating DNA damage repair and maintaining genomic integrity. Here, we report that a p53-induced circular RNA circASCC3 promotes chemotherapeutic resistance by resolving R-loops. Our results reveal that p53 directly activates the transcription of <i>ASCC3</i>, the host gene of circASCC3. In addition, the RNA-binding protein SFPQ is identified to inhibit the formation of circASCC3 by associating with its flanking regions. Importantly, p53 facilitates the formation of circASCC3 by repressing the expression of SFPQ. CircASCC3 has a marginal effect on the survival and growth of cancer cells under normal growing conditions but surprisingly boosts their survival and growth in response to DNA damage stress. Mechanistic analysis reveals that circASCC3 binds to the DEAD-box RNA helicase DDX5 to inhibit its proteasomal degradation. This results in the prevention of R-loop accumulation due to DNA damage, thereby conferring tumor resistance to chemotherapy. Together, our study uncovers that p53 activates circASCC3 to promote R-loop resolution, which maintains genomic stability and potentially contributes to chemoresistance.
Authors
- Qian Hao (ORCID: https://orcid.org/0000-0002-4229-7880)
- Jun Deng (ORCID: https://orcid.org/0000-0002-7644-5853)
- Xianghuo He (ORCID: https://orcid.org/0000-0001-8872-668X)
- Xiang Zhou (ORCID: https://orcid.org/0000-0002-1172-7948)
- Ruixuan Huang (ORCID: https://orcid.org/0000-0001-6820-2440)
- Yu Gan (ORCID: https://orcid.org/0000-0002-5769-6809)
- Bangxiang Xie (ORCID: https://orcid.org/0000-0002-8174-9771)
- Shenglin Huang (ORCID: https://orcid.org/0000-0003-1279-0794)
- Bing Chen (ORCID: https://orcid.org/0000-0003-0168-8532)
- Xiong Chen (ORCID: https://orcid.org/0000-0001-8217-5362)
- Jing Tong (ORCID: https://orcid.org/0000-0002-5649-3524)
- Yajie Chen (ORCID: https://orcid.org/0000-0001-6567-0396)
- Mingming Cao (ORCID: https://orcid.org/0000-0002-6452-2946)
- Yingdan Huang
Institutions
- Shanghai Medical College of Fudan University (CN)
- Nanchang University (CN)
- Capital Medical University (CN)
- Fudan University (CN)
- Fudan University Shanghai Cancer Center (CN)
- First Affiliated Hospital of Jiangxi Medical College (CN)
- Jiangxi Provincial Cancer Hospital (CN)
- Beijing YouAn Hospital (CN)
Publication Details
- Journal
- Proceedings of the National Academy of Sciences
- Published
- 2025-03-11
- DOI
- https://doi.org/10.1073/pnas.2415869122
- Citations
- 5
- Primary Topic
- Circular RNAs in diseases
- Type
- article
- Field-Weighted Citation Impact
- 4.03
Funders
- National Natural Science Foundation of China