A video circulating on social media platforms like TikTok and Facebook claims a broad-spectrum antiparasitic drug used for dogs can cure advanced lung cancer. The drug, fenbendazole (FZ), is an anthelmintic that disrupts tubulin polymerization, which acts as both the micro-skeleton of the cell’s interior and a highway for transport, starving parasites by cutting off their supply of food. It is currently used as a veterinary drug in Canada, and although preclinical studies are exploring fenbendazole’s potential to treat certain cancers, its efficacy has not yet been proven in humans.
A 57-year-old woman with metastatic pulmonary adenocarcinoma receiving pembrolizumab monotherapy developed liver injury after consuming oral fenbendazole. She had obtained information on the antitumor activity of fenbendazole from social media and self-administered the medication to prevent progression of her cancer.
Despite the lack of antitumor activity, fenbendazole had time-dependent inhibitory effects on both 5-FU-sensitive and -resistant CRC cells and promoted cell death by both p53-dependent apoptosis and ferroptosis-augmented apoptosis in a manner similar to albendazole. We further evaluated the molecular mechanisms of fenbendazole’s anti-cancer effect and found that it inhibits proliferation by altering the expression of p21 in CRC cells, leading to G2/M phase arrest and cell cycle repression.
Moreover, fenbendazole promotes apoptosis in SNU-C5 and SNU-C5/5-FUR cells by activating caspase-3 through mitochondrial injury. In addition, it suppresses autophagy and ferroptosis through decreased expression of GPX4 in the cell. These findings suggest that fenbendazole, a benzimidazole with multiple mechanisms of action, is a promising anti-cancer drug to overcome resistance to conventional chemotherapy.fenbendazole for humans cancer