by A fungus-fighting drug that has been used for years to treat parasitic infections in animals appears to also shrink tumors in people with cancer. The Joe Tippens cancer protocol, as it’s called, suggests that patients take 222 mg of the medication, or mebendazole, every day for seven days to prevent a patient’s tumors from growing or spreading while other cancer treatments are used. Mebendazole is available as oral granules or a liquid suspension and can be taken with food to reduce the risk of stomach upset. Although researchers are still unsure exactly how mebendazole works to fight cancer, it appears to act against multiple cell pathways, helping to destroy tumors from within.
According to the Stanford researchers who conducted the studies, mebendazole, which is also known as albendazole, disrupts certain normal cellular functions that viruses and some cancer cells use to grow and spread. The drug targets the protein tubulin, which acts as the micro-skeleton of the inner cell and a highway for transporting proteins to where they’re needed. Mebendazole gets inside the tubulin and causes it to collapse, essentially starving the cancer cells of nutrition. The drug also suppresses a cancer-associated gene that promotes cell growth and blocks the activation of p53, a critical step in triggering apoptosis.
In a study published in the journal Science Translational Medicine, the researchers showed that fenbendazole can kill human colorectal cancer cells in culture and slow the spread of tumors in mice. The team found that fenbendazole killed tumors in mice by preventing them from forming new blood vessels, a process known as angiogenesis. The drug also prevented the formation of lung metastases when it was given to mice with established metastatic colorectal cancer, but not to non-metastatic mice.
Researchers also found that fenbendazole caused the cancer cells to undergo a form of cell death known as ferroptosis, which is triggered by the presence of high levels of free iron in the cells. They confirmed that fenbendazole-induced ferroptosis occurred by measuring the activity of various proteins involved in this process. Treatment of cells with the iron chelator deferoxamine mesylate or the inhibitors ferrostatin-1 and DFOM significantly blocked fenbendazole-induced necroptosis. The researchers also found that fenbendazole augmented the apoptosis-inducing activities of 5-fluorouracil in wild-type but not 5-fluorouracil-resistant SNU-C5 cells.
The Stanford research team hopes to carry out further testing of fenbendazole for humans with cancer, including trials of its combination with other drugs. The scientists note that, though fenbendazole has been used in humans for decades to treat parasitic diseases, it has never been tested in randomized clinical trials for its potential to treat cancer. But the research shows that, by targeting several of the pathways that cancer cells rely on to grow and spread, mebendazole could be a powerful tool for treating many different types of cancers in humans. The work was funded by the Virginia and D.K Ludwig Fund for Cancer Research, the National Institutes of Health and the Center for Medicinal Chemistry at Stanford. fenbendazole for humans cancer
