The ingredient in dog wormers that’s been touted to cure cancer
The anthelmintic agent fenben (also called metronidazole or FLG) has been shown to suppress cancer cells in laboratory settings. However, there isn’t enough evidence that it can prevent recurrent cancer or is safe for humans. There are already a number of established treatments available for people with recurrent cancer, including chemotherapy, immunotherapies and targeted therapies.
In a study published in the journal Nature, researchers investigated fenben’s anti-cancer effects on 5-FU resistant colorectal cancer (CRC) cell lines. The team found that fenben induced apoptosis, cell cycle arrest, and ferroptosis in both wild-type and 5-FU resistant SNU-C5 cells. Moreover, the drug significantly decreased cell viability in both cells, and was more effective at inhibiting 5-FU resistance in p53 mutant cells.
Specifically, fenbendazole binds to the mitochondrion, causing it to break apart and release oxidative stress. This in turn triggers the expression of apoptotic proteins, such as caspase-3 and -7, and apoptosis. Furthermore, fenbendazole increased the expression of autophagy-related proteins, such as LC3 and Atg7. It also suppressed the expression of GPX4, which led to ferroptosis in both SNU-C5 and 5-FU resistant cells.
To evaluate the effectiveness of fenben in reducing tumor growth and metastasis, the researchers used animal models. They first exposed mice to the anthelmintic drug, followed by surgery and radiation therapy. The results showed that fenbendazole reduced tumor growth in the liver and lung, and inhibited metastasis. In addition, fenbendazole also reduced the activity of ERK1/2 and mTOR, which can promote cancer growth.
A similar study conducted by researchers from the University of Massachusetts Amherst found that fenbendazole, an anthelmintic agent, reduced the growth of melanoma skin tumors in mice. The team discovered that fenbendazole inhibits the formation of a protein called cyclin B1. Cyclin B1 is essential for normal cell division, but it is overexpressed in melanoma cells and causes them to grow more rapidly. Similarly, fenbendazole prevented melanoma cells from forming cyclin A and cyclin D, which are also required for normal cell division.
Ultimately, the researchers hope that their findings will help doctors use fenben to treat human cancer patients. They plan to test the drug on human cancers that are resistant to standard chemotherapy agents, such as 5-FU and oxaliplatin. They will also examine the effect of fenbendazole on tumor cell survival and viability. The study was funded by the National Institutes of Health. The authors report no conflict of interest. The full study is available in the journal Nature Medicine.
