The broad-spectrum anti-parasitic drug fenbendazole, which is used to treat parasitic worms in animals like horses, may also be a useful cancer treatment. Scientists have found that fenbendazole has microtubule depolymerizing activity and can alter cancer cell metabolism. Their results were published in the journal Scientific Reports.
The team tested the effect of fenbendazole on different types of human cancer cells. They found that it reduced glucose uptake in cancer cells by disrupting a pathway that normally enables cells to use sugar as energy. This led to a reduction in cell proliferation and death.
They tested the effects of fenbendazole on cancer cells that had been genetically modified to express mutant forms of the protein mitotic spindle assembly factor 2 (MSA2). The team found that fenbendazole interferes with MSA2 function and prevents the formation of the spindle, causing cells to die.
To further explore fenbendazole’s potential as a cancer treatment, the researchers developed a novel delivery system to carry the drug. They encapsulated fenbendazole in a self-assembling polymer called poly(methyl methacrylate) b-poly(ethylene glycol) to form micelles. Micelles have a low PDI (polar/non-polar interface) and high permeability, making them ideal for drug delivery. The researchers then used a mouse model to test the efficacy of the micelles in reducing tumor growth.
The mice received either free fenbendazole or a combination of fenbendazole and the immunotherapy drug rapamycin. After two weeks of injections, the mice that received the fenbendazole/rapamycin mixture showed significantly less cancer tumors than the control group. The fenbendazole/rapamycin micelles also had higher levels of both drugs in their plasma than the free fenbendazole.
The scientists believe that fenbendazole’s dual action on the mitochondria and microtubules could explain its effectiveness against cancer cells. They are continuing to study the drug in other animal models and plan to conduct clinical trials in humans in the future. This research was supported by the Virginia and D.K Ludwig Fund for Cancer Research and by the National Institutes of Health. fenbendazole cancer