Fenben, a drug used to treat parasites in livestock, might also kill cancer cells. A study found that it works by interfering with microtubules, which help give structure to normal cells. It also suppressed growth in human cancer cell lines, and boosted the effects of radiation treatment and other drugs that target tubulin.
Although animal anthelmintics have long been used as anti-parasitic agents, it has only recently been discovered that they may also be effective anti-cancer drugs. Several other benzimidazole antihelminthics, including albendazole (Albendazole), have already been approved as anthelmintic agents for humans. However, turning these findings into an approved drug for patients is a long journey.
To investigate whether fenbendazole can kill cancer cells, researchers tested its effects on A549 human non-small lung cancer xenografts in athymic nude mice. They gave mice fenbendazole orally every second day for 12 days. The tumors were then excised, measured and weighed. Fenbendazole significantly reduced tumor size, and increased apoptosis. It also reduced tumor vascularity, measured by spectrophotometric measurement of hemoglobin in the tumors.
Since fenbendazole is poorly absorbed in the gut, most of the drug passes into the liver and is converted to its sulfone metabolite, which is excreted through the feces. This is why it has low toxicity in ruminants, and why it is not a teratogenic or carcinogenic compound. Nevertheless, pheasants are a small commodity group and are consumed at lower rates compared to commercial poultry species such as chickens or turkeys. Therefore, no pheasant meat consumption data is available to support the use of current FDA liver MRLs and fenbendazole sulfone LODs for determining safe levels of fenbendazole residues in pheasant meat for human consumption. fenben for humans