Human prostate cells grown in a lab. The Decipher test looks at the activity of 22 genes in prostate cancer cells. Credit: NIH
According to a recent laboratory study conducted in 2026, it has been discovered that menadione, a substance that is similar to vitamin K, has the potential to enhance the effectiveness of chemotherapy against prostate cancer cells. The research, which was published in Prostate Cancer, attempted to combine menadione with cabazitaxel, a chemotherapy drug that is often utilised in advanced prostate cancer treatment. The results revealed that the combination was able to slow down the growth of cancer cells more effectively than either treatment alone.
The scientists also discovered changes in the metabolism of the cells and in their genes, which provides an opportunity to better understand how the combination works. These findings are important because cancer cells depend on specific processes to produce energy, grow, and survive. Disrupting these processes may make it more difficult for cancer cells to continue multiplying.
The results of this research also support earlier findings from a 2024 study, which discovered that menadione could disturb the recycling process inside prostate cancer cells. This disruption affected the cells' ability to function normally and helped slow down cancer progression in laboratory mice.
Nevertheless, the 2026 research was conducted in vitro, meaning the experiments were performed on cells in a laboratory rather than in human patients. Therefore, more investigations need to be carried out to determine whether this combination is both effective and safe for application in humans.
It is also important to note that menadione, also known as vitamin K3, is different from vitamin K1 and vitamin K2. It can be harmful to health, particularly at high doses, and should not be used as a cancer treatment without appropriate medical supervision. Although the findings are promising, further research is needed before this approach can be considered a possible treatment for prostate cancer.
Reference:
Gómez-Rosas, A. L., et al. (2026). In vitro effects of cabazitaxel and menadione on human prostate cancer cells. Prostate Cancer. https://doi.org/10.1155/proc/4174599
