A video on TikTok and Facebook claims that a common anthelmintic drug cures cancer in humans. While fenbendazole does reduce tumors in animal studies, it hasn’t been shown to kill cancer cells in people or stop cancer growth in patients. It’s also not approved as a treatment for cancer in Canada or the United States, where it is only available as an antiparasitic for dogs.
The anthelmintic drugs fenbendazole, albendazole and mebendazole are all members of the benzimidazole family and are used to treat parasites in animals. Peer-reviewed studies have examined these drugs and others in the same category as possible cancer treatments, but none has found enough evidence to confirm that they could cure cancer in humans.
These drugs are thought to work by interfering with microtubules, which are important structures that separate chromosomes during cell division. They are involved in several other functions, including cell movement and cell cycle control. They have been found to be toxic for many types of cancer cells, and they have been found to enhance the sensitivity of these cells to radiation.
In this study, we evaluated the effects of fenbendazole on the growth of EMT6 colon carcinoma cells in vitro and on their ability to tolerate radiation. We performed the experiments under either aerobic or severe hypoxic conditions, in order to determine whether hypoxia significantly alters the sensitivity of these cells to fenbendazole. Cells were treated for 2 h with various concentrations of fenbendazole and then assayed using a colony formation assay. Survivals are reported both as surviving fractions and as yield-corrected surviving fractions, which correct for differences in cell numbers between treated and untreated cultures.
Severe hypoxia significantly increased the toxicity of 2-h treatments with fenbendazole, while no significant effect was seen for the same treatment under aerobic conditions. This finding suggests that, in general, severe hypoxia has a more marked impact on the sensitivity of these cells to fenbendazole than does aerobic culture.
In a second set of experiments, we evaluated the effects of three daily i.p. injections of fenbendazole on EMT6 tumors in BALB/cRw mice. The tumors were randomized at a volume of 100 mm3 to serve as controls, or to receive fenbendazole plus radiation. Neither the fenbendazole alone nor the combination of fenbendazole and radiation significantly altered tumor growth or the radiation response. However, these results were in agreement with the in vitro data indicating that high concentrations of fenbendazole have both cytotoxic and cytostatic properties in these tumor cells. fenbendazole for cancer