Fenben, also known as Pancur and Safe-Guard, is a common medication used to treat parasites (roundworms, whipworms, hookworms, tapeworms) and worm infestation in animals (such as cattle). It has recently become popular among cancer patients as an alternative treatment as it is part of the Joe Tippens Protocol. However, little research has been done on its biological effects.
Benzimidazole anthelmintic drugs have been repurposed to overcome drug resistance in cancer cells by interfering with the microtubule network. In this study we found that fenbendazole (FZ) inhibits the growth of human cancer xenografts in nu/nu mice and induces cell death through multiple pathways. In particular, FZ suppresses glucose uptake by blocking GLUT transporters and hexokinase expression. It also interferes with the tubulin polymerization to block ATP formation resulting in loss of cellular energy.
In vitro cytotoxicity tests showed that FZ exhibits a strong anti-proliferative effect in colorectal cancer cells. Time-dependent cell cycle arrest was observed in SNU-C5 and SNU-C5-5-FUR colorectal cancer cells by FZ.
FZ also significantly increased the protein level of p21 and induced apoptosis in 5-fluorouracil-resistant SNU-C5 colorectal cancer cells.
To investigate the biodistribution of FZ and RAPA in vivo, we encapsulated these drugs into different polymers to prepare micelle formulations for the in vivo experiment. Micelle and solution formulations were administered to athymic nu/nu mice that subsequently developed A549 human cancer xenografts. FZ administration led to a significant reduction in tumor size and weight in these mice and reduced tumor vascularity by reducing hemoglobin content as determined by spectrophotometrically measuring hemoglobin in tumor tissue.fenben for cancer