A study from the University of Würzburg has identified peroxiredoxin 6 (PRDX6) as a critical enzyme involved in selenoprotein production, opening potential new avenues for treating specific cancers, particularly neuroblastoma in children. The research highlights that inhibiting PRDX6 could impair cancer cell survival, offering a novel therapeutic target.
Selenoproteins play essential roles in various biological functions, including breaking down harmful substances, supporting the immune system, and regulating metabolic processes. However, certain selenoproteins, such as glutathione peroxidase 4 (GPX4), can protect cancer cells from death. GPX4's protective properties pose a challenge for standard cancer therapies, as its activity promotes the survival of drug-tolerant states.
"If we can inhibit GPX4 production, we may be able to target and destroy cancer cells. This is particularly promising for treating neuroblastoma, which primarily affects children," said Professor Pedro Friedmann Angeli, chair of Translational Cell Biology at the University of Würzburg.
Discovery of PRDX6's Role
In collaboration with researchers from the Heidelberg Institute for Stem Cell Technology and Experimental Medicine, the team focused on inhibiting enzymes that promote selenocysteine insertion into selenoproteins. Zhiy Chen, a PhD student in Friedmann Angeli's team, explained, "Until now, we only knew of one enzyme, selenocysteine lyase (SCLY), which was responsible for releasing the selenium atom from selenocysteine. Our research has now identified an unforeseen pathway that requires the enzyme, peroxiredoxin 6 (PRDX6), which can sustain selenoprotein production without SCLY."
Using advanced techniques like mass spectrometry and CRISPR-Cas9-based functional genomics, the researchers discovered that PRDX6 binds directly to selenium and acts as a transporter, enabling the production of new selenoproteins. The study demonstrated that inhibiting PRDX6 could impair cancer cell survival, especially in neuroblastomas, suggesting a new potential therapeutic target.
Implications for Cancer Treatment
Interestingly, the team found that while PRDX6 can compensate for the absence of SCLY, it lacks the specific activity required to remove the selenium atom from its precursors. The Friedmann Angeli group plans to investigate which other proteins collaborate with PRDX6 to maintain selenium protein synthesis. Furthermore, they aim to develop molecular inhibitors targeting both SCLY and PRDX6 to more effectively hinder cancer cell growth.
The collaborative study involved partners from the University of São Paulo in Brazil, the Institute of Stem Cell Technology and Experimental Medicine in Heidelberg, and the German Cancer Research Center (DKFZ).
