Full Fact: A benzimidazole that is used to treat parasites in dogs, fenbendazole, also known as methiazole, has been found to have anti-cancer effects. It targets microtubules in cancer cells by inhibiting their polymerization.
Fenbendazole triggers apoptosis in 5-FU-sensitive SNU-C5 and SNU-C5/5-FUR CRC cells without activating mutant p53, and it induces ferroptosis augmented by decreased expression of the autophagy inhibitors GPX4 and SLC7A11.
Cell cycle arrest
The antiparasitic drug fenbendazole causes cancer cells to undergo cell cycle arrest and triggers apoptosis, autophagy, and ferroptosis. It binds to beta-tubulin and disrupts microtubules, preventing their assembly into the mitotic spindle. It also inhibits glucose uptake and decreases glycogen stores. As a result, fenbendazole induces apoptosis through the mitochondrial caspase-3-poly (ADP-ribose) polymerase pathway. This drug is also known to bind phosphorylated histone H3 and induce DNA damage. In addition, it binds to adenosine triphosphate, a key energy substrate. This drug may also reduce cellular viability and differentiation.
A recent study found that fenbendazole inhibits the proliferation of human melanoma cells by blocking cyclin D and CDK4/6 activity. This effect is accompanied by an accumulation of DNA damage, which may be associated with genomic instability and tumor formation.
Another effect of fenbendazole is the inhibition of mitotic spindle assembly by blocking the mitotic checkpoint. This leads to mitotic catastrophe, which can lead to aneuploidy. Aneuploidy is correlated with tumor recurrence and resistance to standard chemotherapy regimens.
In SNU-C5 and SNU-C5/5-FUR CRC cells, fenbendazole induced G2/M phase arrest and apoptosis in both wild-type and mutant p53 cells. This apoptosis was mediated by p53-p21 pathways and partially by autophagy and ferroptosis. However, the activation of apoptosis and autophagy was reduced in mutant p53 cells due to decreased expression of LC3 and Atg7.
Apoptosis
Fenbendazole belongs to a class of drugs called benzimidazole carbamates. The drug is used to treat parasites in animals, but it may also kill cancer cells. Research has shown that fenbendazole can prevent the spread of pancreatic cancer in mice and inhibit the growth of breast cancer in vitro. Other studies have found that other drugs in this class, such as mebendazole and pyrantel tetracycline, can reduce cancer cell proliferation.
A video posted on TikTok and Facebook by a veterinarian has claimed that the dog deworming medicine fenbendazole can cure advanced lung cancer. The post, which has received millions of views on social media, is based on the anecdotal account of Joe Tippens, who says his rare form of lung cancer went into remission after he took fenbendazole. However, a veterinary oncologist tells AFP that this claim is unsubstantiated.
The researchers found that fenbendazole significantly reduced the growth of human tumor cells, and caused apoptosis and cellular cycle arrest. The results were published in the journal Scientific Reports.
The benzimidazole family of drugs acts by binding to tubulin microtubules and disrupting their equilibrium. This causes a disruption in the mitotic spindle, a structure that separates the chromosomes during cell division. The chromosomes must be separated evenly in order to divide properly. If the chromosomes are not divided equally, they will be damaged and may be unable to replicate. Damaged chromosomes are more likely to become malignant and cause disease.
Necroptosis
A benzimidazole drug, fenbendazole is widely used as an antiparasitic agent against various parasitic infections in animals. It exerts its anthelmintic effects by binding to b-tubulin microtubule subunits and disrupting their polymerization. Recently, it has been found to exhibit cytotoxic activity against cancer cells in vitro. It inhibits the growth of tumor cells and causes mitotic slippage, which is one of the earliest events in cell cycle arrest.
Although fenbendazole is effective against cancer in some studies of cancer cells grown in petri dishes and mice, there isn’t enough evidence from randomized clinical trials that it can cure cancer in humans. In addition, many patients who claim to be cured of their cancer say they took fenbendazole along with other conventional treatments and may therefore not represent the typical patient experience.
The relapsed colon cancer patient who was the subject of Jones’ TikTok video claimed to have cured himself of his rare cancer by taking fenbendazole along with immuno-cancer treatments in a clinical trial. However, the video didn’t include any details about his other cancer treatments and his anecdotal remission wasn’t backed by medical research. In addition, fenbendazole isn’t FDA-approved for use in humans and could cause serious side effects. The nonprofit organization Cancer Research UK told Full Fact that there’s no proof that fenbendazole can cure cancer, and the drug hasn’t been tested in humans during randomized clinical trials to prove it’s safe or effective for this purpose.
Toxicity
Fenbendazole is an anthelmintic used to treat parasitic worms such as ascarids, whipworms, hookworms, and a single species of tapeworm in humans and animals. It is absorbed in the gastrointestinal tract and converted to its active metabolites, fenbendazole sulfone and oxifendazole. These compounds exhibit antiparasitic and anti-inflammatory activities, as well as antitumor activity in animal models. In addition, they have low toxicity in humans and are cheap as generic drugs. Therefore, they have a high potential for repurposing as anticancer drugs.
The repurposing of drugs to treat cancer has gained momentum in the medical community. This strategy can help shorten drug development times and reduce costs compared to the traditional drug discovery process. It is also a promising strategy for treating drug-resistant tumors. The benzimidazole family of antiparasitic drugs, including mebendazole (MBZ), albendazole (ABZ), and flubendazole (FZ), have been investigated for their potential to treat cancer. They have been shown to inhibit the proliferation of colonic carcinoma cells and induce apoptosis through activation of the caspase-3/PARP pathway.
In addition, fenbendazole has been shown to suppress microtubule formation and to inhibit RAS-related signaling pathways in human cancer cells. However, its anticancer activity hasn’t been tested in randomized clinical trials. As a result, the FDA and other medical organizations warn patients against taking fenbendazole to treat their cancers. Despite this warning, TikTok and Facebook users continue to make claims about the use of fenbendazole to treat fenbendazole for cancer
