Related Experiment Video
Updated: Jun 6, 2026

Revealing the Ferroptotic Phenotype of Medulloblastoma
Published on: March 15, 2024
Discovery of ferroptosis-inducing R4VP compounds for targeting aggressive cancers
Avital Oknin-Vaisman1, Deepanjan Panda2, Rostislav Novak1,3
1Rappaport Research Institute and Faculty of Medicine, Ruth and Bruce Cancer Research Center (RTICC), Technion-Israel Institute of Technology IIT, Haifa, Israel.
Abstract:
Aggressive and therapy-resistant cancers present a significant challenge to treatment and are associated with poor patients' survival. Identifying molecular pathways and compounds that target these pathways is critical for improving patient outcomes. RNF4, an E3 Ubiquitin ligase, is pivotal for tumorigenesis in part by stabilizing oncoproteins and its role in DNA repair, thereby enhancing cancer cell survival and driving tumorigenesis. Elevated RNF4 levels are associated with poor prognosis in patients with carcinomas, melanoma, and sarcoma. Here, we describe the design and development of R4VPs, dual degrader compounds connecting two E3 ubiquitin ligases; Von Hippel-Lindau protein (VHL) with RNF4. R4VPs promote RNF4 degradation and thereby reduce the levels of its stabilized phosphorylated oncoproteins, while concomitantly eliminating VHL. R4VPs selectively induce ferroptotic cell death in cancer cells, sparing non-tumorigenic and primary cells in part by binding and modifying the anti-ferroptotic selanoproteins GPX4. R4VPs-induced ferroptosis preferentially targeting cells harboring tumor-driving mutations in the EGFR pathway, whereas it does not affect PI3K-transformed cells. As a consequence, R4VPs effectively induce cell death in Receptor Tyrosine Kinase inhibitor-resistant melanoma and primary patient sarcoma cells. Our findings highlight the potential of selective ferroptosis inducers, such as R4VPs, as a therapeutic strategy for hard-to-treat cancers.
Insights
New dual-acting compounds called R4VPs degrade the RNF4 E3 ubiquitin ligase, selectively inducing cancer cell death via ferroptosis. This offers a promising new therapy for aggressive, treatment-resistant cancers.
Area of Science:
- Oncology
- Molecular Biology
- Drug Development
Background:
- Aggressive and therapy-resistant cancers pose significant treatment challenges and are linked to poor patient survival.
- RNF4, an E3 ubiquitin ligase, promotes cancer cell survival and tumorigenesis by stabilizing oncoproteins and aiding DNA repair.
- Elevated RNF4 levels correlate with poor prognosis in various cancers, including carcinomas, melanoma, and sarcoma.
Purpose of the Study:
- To design and develop novel dual degrader compounds (R4VPs) targeting RNF4 for cancer therapy.
- To investigate the mechanism of R4VPs in inducing cancer cell death.
- To evaluate the efficacy of R4VPs in therapy-resistant cancer models.
Main Methods:
- Design and synthesis of R4VPs, dual degraders linking Von Hippel-Lindau protein (VHL) with RNF4.
- Assessment of RNF4 degradation and oncoprotein levels upon R4VP treatment.
- Evaluation of R4VPs' effect on cancer cell viability and induction of ferroptosis, including interaction with GPX4.
- Testing R4VPs efficacy in cancer cells with specific mutations (EGFR, PI3K) and in resistant melanoma and sarcoma models.
Main Results:
- R4VPs successfully promote RNF4 degradation and reduce stabilized oncoproteins.
- R4VPs selectively induce ferroptosis in cancer cells, sparing normal cells.
- Ferroptosis induction by R4VPs is linked to GPX4 modification.
- R4VPs preferentially target cancer cells with EGFR pathway mutations and demonstrate efficacy in resistant melanoma and sarcoma cells.
Conclusions:
- R4VPs represent a novel therapeutic strategy by selectively inducing ferroptosis in cancer cells.
- Targeting RNF4 degradation offers a promising approach for treating aggressive and therapy-resistant cancers.
- The findings highlight the potential of R4VPs as a new class of drugs for difficult-to-treat malignancies.
Related Concept Videos
Targeted Cancer Therapies
There are several types of targeted therapies against specific...
Targeted Cancer Therapies
There are several types of targeted therapies against specific...
Rous Sarcoma Virus (RSV) and Cancer
RSV is a retrovirus that contains two copies of a plus-strand RNA genome. Its genome consists of four main open...
Rous Sarcoma Virus (RSV) and Cancer
RSV is a retrovirus that contains two copies of a plus-strand RNA genome. Its genome consists of four main open...
Treatment Resistent Cancers
Treatment Resistant Cancers
