Pancreatic cancer is one of the deadliest tumor types, and it can develop resistance to chemotherapies and even newer immunotherapy drugs. But a study in mice suggests that a combination of a chemotherapy drug and two drugs designed to unleash the immune system could eliminate pancreatic cancer cells.
A claim has circulated that fenbendazole can cure cancer. While some studies using cancer cells in Petri dishes and mice suggest that it might, the claim is false.
Dosage
Fenbendazole is a common antihelminthic drug used to treat parasites such as roundworm and hookworm. It has also been shown to kill cancer cells in laboratory tests. It works by blocking the formation of microtubules, a protein scaffolding in cells that establishes their shape and structure. Cells need these structures to transport organelles and cargo within the cell. Textbook depictions of cells often portray them as amorphous bags of liquid, but the cytoskeleton gives each cell its shape and enables it to travel.
In a series of experiments, scientists tested the ability of high doses of fenbendazole to kill EMT6 mammary tumor cells in culture and to inhibit the growth of paclitaxel-resistant tumors in mice. They found that 2-h treatments of fenbendazole reduced the number of EMT6 cells in cultures, while 24-h treatment significantly reduced paclitaxel-resistant tumors. The researchers also found that combining fenbendazole and paclitaxel increased the toxic effects of both drugs.
Scientists also irradiated tumors in genetically engineered mice and then treated them with three daily fenbendazole injections or a combination of fenbendazole plus 10 Gy of radiation. They found that fenbendazole alone did not prevent the development of new tumors, but in combination with irradiation it prevented the emergence of new local tumors and significantly increased survival.
Side effects
The pancreas is located deep inside the abdomen behind the stomach and produces enzymes that help digest food, regulate blood sugar and produce hormones. Cancer of the pancreas, known as ductal adenocarcinoma, is usually only detected in its advanced stages when it starts to spread beyond the organ.
A common anthelmintic (drug that kills parasites and worms) called fenbendazole has been shown to be effective against the cancer of the pancreas in lab experiments. It has a long history of safe use in humans.
The researchers tested the effect of four benzimidazole-based anthelmintics — fenbendazole, mebendazole, oxibendazole and parbendazole — on pancreatic cancer cells. They found that parbendazole was more effective than the others in preventing cell growth, causing DNA damage, inducing apoptosis and reducing cellular migration.
The scientists also analyzed the cellular mechanisms by which the drugs worked. They found that fenbendazole disrupts microtubules, stabilizes the cell’s protective p53 protein and interferes with the cancer cells’ glucose metabolism.
Interactions with other medications
A group of drugs called benzimidazoles, including mebendazole, albendazole, flubendazole, and fenbendazole, has been found to inhibit the growth of various types of cancer cells. They act as microtubule disruptors and interfere with glucose uptake. They can also enhance the activity of p53 tumor suppressor genes.
Researchers have also discovered that the anti-parasitic drug mebendazole can stop pancreatic cancer in its tracks by starving cancer cells of their supply of fuel. The team gave the drug to genetically engineered mice that developed pancreatic cancer and measured the level of inflammation, tissue change, and the stage, grade, and metastatic status of the cancer.
But despite the claims made by Joe Tippens, there is no evidence that fenbendazole can cure cancer. As Full Fact notes, the anecdotal evidence consists of just one patient who was able to halt his cancer’s progression by taking fenbendazole. This claim didn’t pass any medical tests or clinical trials, so it should be taken with a grain of salt.
Safety
Although fenbendazole may slow cancer growth in lab studies of cells and mice, there’s not enough evidence to show that it cures pancreatic cancer in humans. Anecdotal reports from a few people who say they went into remission after taking fenbendazole aren’t reliable. It could be that other factors, such as conventional cancer treatments they were receiving at the same time, contributed to their remission.
Fenbendazole targets the protein tubulin, which helps establish shape and structure in cells. It interferes with how it forms, causing cell structures to collapse. This includes the micro-skeleton of the inner cell and a pathway used for transporting organelles or cargo.
The team found that fenbendazole, along with three other FDA-approved benzimidazole-based anthelmintics — mebendazole, oxibendazole and parbendazole — significantly reduced the viability of two pancreatic cancer cell lines. The drug inhibited growth, clonogenic activity and migration, altered microtubule organization, affected autophagy and promoted DNA damage responses in the cancer cells. It also synergized with the first-line chemotherapy gemcitabine in a cell-based assay. fenbendazole for pancreatic cancer