Related Experiment Video
Updated: Apr 8, 2026
Genome-Wide CRISPR Screen for Unveiling Radiosensitive and Radioresistant Genes
Published on: May 23, 2025
In vivo CRISPR/Cas9 Screening Reveals that UBE2L3 Modulates Autophagic Flux through TSC2 Ubiquitination and
Jian Xu1, Ling Cheng2, Sien Ma3
1Department of Surgical Oncology, The First Affiliated Hospital of Bengbu Medical University, Bengbu, Anhui, China.
Abstract:
Triple-negative breast cancer (TNBC), a distinct breast cancer subtype, poses significant challenges to conventional therapeutic approaches, and effective targeted therapies are limited. CRISPR/Cas9 library screening has demonstrated unprecedented efficiency and revolutionary potential in the identification of therapeutic targets. In this study, we performed In vivo CRISPR/Cas9 library screening and identified the E2 ubiquitin-conjugating enzyme UBE2L3 as a critical regulatory factor in the progression of TNBC. Loss of UBE2L3 restricted tumor cell growth by modulating autophagy in TNBC cells. Mechanistically, UBE2L3 downregulation led to increased tuberous sclerosis complex 2 (TSC2) expression, suppressing mTOR activity and altering autophagic processes in tumor cells. This regulation was mediated through the interaction between UBE2L3 and the E3 ubiquitin ligase SMURF2, which together control TSC2 protein ubiquitination and degradation. Autophagy and the tumor microenvironment are closely associated, and we observed that UBE2L3 knockdown in TNBC tumors significantly increased CD8+ T lymphocyte infiltration and enhanced tumor sensitivity to anti-PD-1 therapy. Collectively, our findings provide a theoretical foundation for considering UBE2L3 as a potential therapeutic target in TNBC.
Insights
Researchers identified UBE2L3 as a key factor in triple-negative breast cancer (TNBC) progression. Inhibiting UBE2L3 restricts tumor growth by altering autophagy and enhancing immunotherapy response.
Area of Science:
- Oncology
- Molecular Biology
- Cancer Genetics
Background:
- Triple-negative breast cancer (TNBC) lacks targeted therapies, necessitating novel treatment strategies.
- CRISPR/Cas9 screening is a powerful tool for identifying therapeutic targets in cancer.
Purpose of the Study:
- To identify novel therapeutic targets for TNBC using in vivo CRISPR/Cas9 screening.
- To elucidate the role of UBE2L3 in TNBC progression and its underlying mechanisms.
Main Methods:
- In vivo CRISPR/Cas9 library screening was employed to identify genes regulating TNBC.
- Functional assays were performed to assess the impact of UBE2L3 on tumor cell growth, autophagy, and the tumor microenvironment.
- Protein interaction and ubiquitination assays were conducted to investigate the mechanism of UBE2L3 action.
Main Results:
- UBE2L3 was identified as a critical regulator in TNBC progression.
- Loss of UBE2L3 restricted tumor growth by modulating autophagy via the UBE2L3-SMURF2-TSC2 axis, leading to mTOR inhibition.
- UBE2L3 knockdown increased CD8+ T cell infiltration and enhanced sensitivity to anti-PD-1 therapy in TNBC models.
Conclusions:
- UBE2L3 plays a significant role in TNBC growth and immune evasion.
- Targeting UBE2L3 presents a potential therapeutic strategy for TNBC, possibly in combination with immunotherapy.
