Could a medication used to prevent blood clots reveal a new way to weaken cancer cells? This question has begun to attract the attention of the scientific community following recent research on warfarin, a well-known anticoagulant that is being studied for its possible relationship with a cell death mechanism called ferroptosis.
This development is interesting because it does not involve a newly developed medication, but rather a drug with a well-established medical use. However, it is essential to understand what this really means: warfarin is not currently an approved cancer treatment. The evidence available so far comes mainly from laboratory experiments and animal models. Even so, these findings could help identify new vulnerabilities in certain tumors and guide future, more precise therapies.
The Link Between Cancer and Blood Clots
In people with cancer, blood coagulation may behave differently. Some tumors produce substances that promote the formation of blood clots, while certain treatments, surgeries, venous catheters, prolonged immobility, or advanced disease can also increase this risk. One of the main complications is venous thromboembolism, which includes deep vein thrombosis — a clot generally located in the legs — and pulmonary embolism, which occurs when a clot reaches the lungs.
For this reason, anticoagulants are already part of the medical care of some patients with cancer. Their usual function is to prevent or treat events related to blood clotting, not to directly fight the tumor. The medication selected depends on many factors, such as the type of cancer, the treatment the patient is receiving, the risk of bleeding, kidney function, possible interactions with other drugs, and each person’s individual characteristics.
Available options include low-molecular-weight heparins, certain direct oral anticoagulants, and, in specific situations, warfarin. The latter requires careful monitoring, since its action can be influenced by other medications, changes in diet, and different health conditions.
A New Line of Research on Warfarin
In addition to its anticoagulant function, warfarin is being examined from a different perspective. A study published in Cell Metabolism investigated a protein called VKORC1L1, which is related to vitamin K metabolism and to the ability of certain cells to defend themselves against oxidative damage.
In simple terms, cells need protective systems that prevent their membranes from deteriorating. Some tumor cells can take advantage of these systems to continue surviving, even when they are exposed to stressful conditions. The VKORC1L1 protein appears to participate in one of these protective mechanisms by promoting antioxidant activity related to vitamin K.
Researchers observed that warfarin can interfere with this pathway. In experimental studies, by blocking activity related to VKORC1L1, some cancer cells became more vulnerable to ferroptosis. In addition, in animal models, this strategy was associated with reduced tumor growth, especially in experimental models of pancreatic cancer.
What Is Ferroptosis and Why Is It Relevant in Cancer?
Ferroptosis is a regulated form of cell death that depends on iron. It occurs when oxidative damage accumulates in the fats that make up the cell membranes. When this damage exceeds the cell’s defensive capacity, the membrane loses its stability and the cell dies.
Tumors often grow in demanding environments, with limited nutrients, inflammation, and high levels of metabolic stress. If a tumor cell is particularly dependent on a protective system to avoid ferroptosis, blocking that system could make it more vulnerable.
This possibility is especially relevant in tumors that are difficult to treat or resistant to certain current therapies. Nevertheless, important questions remain: Which types of cancer would be more sensitive? How can patients who might benefit be identified? How can ferroptosis be induced in the tumor without affecting healthy tissues? These are questions that must still be addressed through well-designed clinical studies.
Can Warfarin Currently Be Used to Treat Cancer?
Warfarin continues to be a medication primarily indicated for preventing or treating problems related to blood clot formation. There is currently no approved indication for using it as a direct cancer treatment.
This clarification is very important because warfarin can cause serious adverse effects, especially bleeding. It can also interact with medications used in oncology, antibiotics, supplements, and significant changes in diet. In patients with cancer, whose treatments can be complex and whose bleeding risk may vary, any decision related to anticoagulants must be carefully evaluated by the medical team.
Figure 1. Warfarin may inhibit the VKORC1L1-associated vitamin K protective pathway, reducing antioxidant defense and increasing lipid membrane damage. This accumulation of oxidative injury may promote iron-dependent cancer cell death, known as ferroptosis.
Therefore, no person should start taking warfarin, change their dose, or discontinue it based on news about recent research. Patients who already use this medication under medical indication should continue following their specialist’s recommendations.
Main reference:
Yang, X., Wang, Z., Zandkarimi, F., Liu, Y., Duan, S., Li, Z., Kon, N., Zhang, Z., Jiang, X., Stockwell, B. R., & Gu, W. (2023). Regulation of VKORC1L1 is critical for p53-mediated tumor suppression through vitamin K metabolism. Cell metabolism, 35(8), 1474–1490.e8. https://doi.org/10.1016/j.cmet.2023.06.014
Other references:
Liu, X., Zhuang, L., & Gan, B. (2023). Unleashing ferroptosis for cancer therapy with warfarin. Trends in endocrinology and metabolism: TEM, 34(11), 683–684. https://doi.org/10.1016/j.tem.2023.08.008
Zhou, Q., Meng, Y., Le, J., Sun, Y., Dian, Y., Yao, L., Xiong, Y., Zeng, F., Chen, X., & Deng, G. (2024). Ferroptosis: mechanisms and therapeutic targets. MedComm, 5(12), e70010. https://doi.org/10.1002/mco2.70010
