Fenbendazole, a benzimidazole, is a broad-spectrum antiparasitic agent with good safety track record in animals. It also shows antitumor effects and inhibits microtubule-associated tubulin polymerization.
Most patients (B, J, L, and P) first obtained information on fenbendazole through acquaintances or TV news. However, some (C and U) also accessed YouTube.
Antiparasitic
Scientists have found that fenbendazole, an antiparasitic drug used to treat parasitic worm infections in animals, can also be used to kill cancer cells. Their research is published in the journal Scientific Reports.
The team tested the effectiveness of fenbendazole on EMT6 colorectal cancer cells in vitro. The cells were treated with varying concentrations of fenbendazole for 2 or 24 h and assayed using a colony formation assay. The results showed that fenbendazole significantly reduced the clonogenicity of the cells. These effects were attributed to mitochondrial injury and caspase-3-augmented apoptosis.
The team also observed that fenbendazole suppressed autophagy in the cancer cells and increased ferroptosis, which may augment apoptosis. They also found that the cytotoxic activity of fenbendazole in 5-fluorouracil-resistant SNU-C5 cells did not require the protein p53. They also discovered that fenbendazole activated the necroptosis-related proteins RIP, RIP3 and MLKL. The scientists believe that the findings could help researchers develop effective treatments for pancreatic cancer.
Antitumor
The antiparasitic medication mebendazole has potential to treat human cancer because parasite cells behave in a similar way to cancer cells. Unlike most drugs, anthelmintics kill parasites without harming normal cells. However, converting research findings into an approved cancer treatment is a long journey.
Several studies have found that fenbendazole is a potent antitumor agent in mice. The drug is given orally in granules or as a liquid suspension and should be taken seven days a week. It is recommended that patients consume it with food to avoid any gastrointestinal upset.
The research team studied the effects of fenbendazole on EMT6 cancer cell growth in BALB/c mice. The tumors were surgically removed and measured. They were then randomly assigned to three different groups: untreated, irradiated alone, or irradiated with fenbendazole and x-rays. Tumor growth was rigorously compared by calculating the time needed for each tumor to grow from its initial volume to four times that volume. The results showed that fenbendazole did not alter the growth of unirradiated or irradiated tumors.
Cytotoxic
Fenbendazole has been shown to have cytotoxic effects in various cancer cell lines. These effects are due to its inhibition of microtubule polymerization. These polymers are responsible for the organization and structure of cells. This cytotoxic activity is similar to that of other anticancer agents, such as the vinca alkaloids and taxanes.
Moreover, fenbendazole induces necroptosis and apoptosis in 5-FU-sensitive and resistant CRC cells. It also suppresses expression of GPX4 and enhances autophagy via beclin-1 in colorectal cancer cells.
To determine whether fenbendazole has cytotoxic effects on human cancer cells, researchers measured the survival of EMT6 cells in vitro after treatment with varying doses of the drug for 2 or 24 h. Survivals were assayed using a colony formation assay. The data showed that fenbendazole significantly reduced the survival of EMT6 cancer cells. This effect was most pronounced at high concentrations and for long incubations. The researchers suggest that fenbendazole may be a useful addition to the existing arsenal of anticancer drugs.
Inhibitor of microtubule-associated tubulin polymerization
A benzimidazole carbamate drug, fenbendazole has been used to fight parasites in animals by cutting off their supply of nutrition. It works by blocking the transport of sugar in the parasite’s gut and collapsing the microtubules that make up the cell’s skeleton and highway. It could have a similar effect on cancer cells, which also use microtubules to get around the cell and steal nutrients from other cells.
The researchers tested the effect of fenbendazole on tumor growth in mice. They carefully measured tumor volume and waited for each one to reach 1000 mm3. Then, they treated the mice with either fenbendazole alone or in combination with a cytotoxic agent. They calculated the time it took for each tumor to grow from its original volume to four times that volume, and then compared this to the results of groups that received other treatments.
They also added fenbendazole to cultures before irradiating them and then analyzed the resulting survival curves. They found that fenbendazole did not alter the radiation dose-response curves in aerobic or hypoxic EMT6 cultures.fenbendazole for cancer
