High Doses of Selenium May Protect Against Ovarian Cancer

A new study, published in Redux Biology, finds that high doses of selenium have anti-cancer properties.

Selenium has been investigated as a potential anti-cancer agent for the reduction of the risk of different malignancies including colorectal, lung, and prostate cancer, as well as an adjuvant to conventional anti-tumour therapies. Such use is limited, however, by the narrow therapeutic window of selenium, since exceeding the daily recommended dose of 60–70 μg can lead to serious illness such as selenosis that occurs at doses above 400 μg. Nanoparticle formulations of selenium, on the other hand, have proven to be more tolerated in vivo than aqueous/organic selenium.  (Toubhans et al., 2023).

Swansea University and Université Grenoble Alpes, worked with selenium nanoparticles. They found them to be highly effective at killing ovarian cancer cell models grown in 3D to replicate the native tumor environment.

Researchers also identified a new biological mechanism that explains how selenium causes this anti-cancer effect. Specifically, selenium alters the activity of enzymes called histone methyltransferases, which regulate epigenetic processes that alter how genes function. Unlike genetic mutations, epigenetic changes are reversible but can change how the body reads a DNA sequence.

These observations provide important new insights into the action of selenium nanoparticles. It is now important to consider both the classic antioxidant and novel histone methylation effects of this key redox element in its development in cancer therapy and other applications. 


Toubhans, B., Alkafri, N., Quintela, M., James, D. W., Bissardon, C., Gazze, S., Knodel, F., Proux, O., Gourlan, A. T., Rathert, P., Bohic, S., Gonzalez, D., Francis, L. W., Charlet, L., & Conlan, R. S. (2023). Selenium nanoparticles modulate histone methylation via lysine methyltransferase activity and S-adenosylhomocysteine depletion. Redox Biology, 61, 102641. https://doi.org/10.1016/j.redox.2023.102641

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