The anthelmintic drug fenben, marketed as a dog dewormer, is being promoted on social media sites like Facebook and TikTok as a cancer cure. But Health Canada says there is no scientific evidence it can treat human cancer.
FZ alters tubulin acetylation, as shown by uptake of the fluorescent glucose analogue 2-NBDG in A549 and H460 cells. It also reduces glycolysis by inhibiting GLUT transporters and the activity of hexokinase II in cancer cells.
Effects
Fenbendazole has been shown to have pleiotropic effects on cancer cells, resulting in cell death. This is thought to be due to its disruption of microtubule dynamics, modulation of p53 signaling and interference with glucose metabolism.
This may explain why anthelmintic drugs like fenbendazole are used to treat animals before they can be released into the wild or transported between facilities as part of quarantine protocols. These drugs are not considered to be toxic to humans and are currently being researched as possible cancer treatments.
2-h treatments of EMT6 cells with fenbendazole produced no changes in cell numbers, even at concentrations approaching the limit of solubility. However, 24-h incubations with fenbendazole significantly decreased both the number of cells in the cultures and their clonogenicity.
The cytotoxic effect of fenbendazole was enhanced by severe hypoxia, as evidenced by the steepness of the dose-response curve for hypoxic cultures treated with a limiting concentration of drug. This effect is likely due to a pronounced binding of fenbendazole and its metabolites to avian -tubulins. These observations are consistent with the known binding of colchicine to mammalian -tubulin and its ability to induce depolymerization of microtubules through this interaction. This demonstrates that -tubulin is an important target for antiparasitic agents. This interaction also provides a rationale for developing compounds that act on multiple targets.
Dosage
Fenben is a member of the broad-spectrum benzimidazole carbamate family and has been safely used as an anthelmintic for roughly six decades. It works by binding to a protein called tubulin in the cell’s microtubule structure. Textbook depictions of cells often show them as amorphous bags of fluid, but in reality they establish their shape and structure through the protein scaffolding of the cytoskeleton, which is made up of microscopic fibers (microtubules).
In humans, fenbendazole is known as Prohibit and is an effective antiparasitic at doses of 1.0 g and 1.5 g per person. It is a popular choice in the United States for treatment of hookworms including Necator americanus and Ascaris lumbricoides, and it also reduces egg counts in patients with gastrointestinal trematodes such as Heterobilharzia americana and Platynosomum fastosum.
In the laboratory, fenbendazole has been found to prevent cancer cell growth and kill tumors in mice. It’s possible that it could do the same in people with cancer, but only time will tell.
Precautions
Fenbendazole can cause irritation to the skin, eyes and lungs if handled incorrectly. It is important to avoid direct contact with these areas and inhalation of granule dust. If accidental skin or eye contact occurs, wash immediately with plenty of water and seek medical advice. It is toxic to humans and should not be ingested if swallowed accidentally. If a human accidentally ingests this medication, they should consult their physician or local poison control center immediately.
Various monitoring tests may be recommended, depending on the pet’s health status and other medications they are taking. Your veterinarian will perform a fecal exam to check for the presence of internal parasites and determine if any additional treatment is necessary.
Most medicines come with special warnings and precautions. Always follow your doctor’s or pharmacist’s instructions, and refer to the medicine package for more information. Medications should not be discarded down the drain or flushed, as they can contaminate the environment. See your doctor or pharmacist for more details about safe drug disposal. Some medicines, such as antidepressants and sedatives, may have a potential for addiction or abuse.