How do fenbendazole and mebendazole work?
Fenbendazole induces mitosis by blocking the cancer cells’ ability to separate chromosomes during cell division.
Fenbendazole, available in suspension, granules, or paste, is administered orally to animals. It is part of a class of drugs called benzimidazoles and deworms dogs, horses, and other farm animals by interfering with parasitic worms’ ability to absorb nutrients, starving the parasite. Mebendazole, approved for human use in the 1970s, is also a benzimidazole and is specifically prescribed by doctors to treat worms and other parasites in humans. In contrast, fenbendazole is prescribed only by veterinarians for use in animals. Both drugs have a long history of safe usage, with mebendazole used in humans for over fifty years, including children and adults. Both are produced globally, cost little per dose, and are available over the counter in many countries. Their lack of toxicity, even with extended use, has sparked interest in their potential for long-term or higher-dose research, including cancer studies.
Since cancer cells divide and grow uncontrollably, fenbendazole is presented as a drug that may interfere with that process.
Microtubule destabilization, disruption of function, similar to chemotherapy
Cell cycle arrest
Interference and blocking of glucose uptake in cancer cells
Mitotic Inhibition
Encouraging programmed cell death in cancer (apoptosis)
What happens to the cancer when it reacts with fenbendazole?
The process of cell division and reproduction is disrupted (stops growing)
Nutrients, such as glucose, may be less absorbed, which could starve the cancer.
As the cancer dies, the tumor cells may be degraded and marked for natural elimination from the body.
Fenbendazole works gradually, and treatment with the drug requires continuous exposure and longer-term use for proper effect. A few days or weeks of taking fenbendazole are not enough to achieve the full effect. Also, if you take fenbendazole without a fat supplement and it is not absorbed, the patient will not receive the full benefits of this protocol. Fenbendazole does not dissolve in water; it requires fat to combine with in your stomach for absorption into the human body. If you take the drug for an extended period of time and it is not being absorbed, you will not receive the cancer-fighting benefits.
At the cellular level, microtubule destabilization disrupts the internal tubular structures that serve as a scaffolding, helping cancer cells distribute chromosomes during cell division. This process of division is called mitosis, and it is fundamental for the reproduction of cancer cells. Unlike normal cells, most cancer cells divide and grow uncontrollably during mitosis. Cancer cells’ wild division is destructively unstoppable. This interference with cancer cell division, caused by fenbendazole, arrests the cell cycle and can slow or block cancer growth in animals and humans. Fenbendazole also has the potential to slow or stop the spread of cancer throughout the human body.
Additionally, during this destabilization process, fenbendazole also induces mitosis by blocking the cancer cells’ ability to separate chromosomes during cell division. This inability to divide leads to programmed cell death known as apoptosis. This entire process naturally eliminates cancer cells from the human body.
Fenbendazole’s first positive cancer results were discovered by accident when lab mice, being treated for routine parasite control, demonstrated an unexpected resistance to experimental cancers. Further investigation revealed:
The ability to inhibit tumor growth in various cancers.
Selective cytotoxicity targeting cancer cells.
Minimal impact on surrounding healthy cells.
Synergistic effects alongside conventional treatment, such as chemotherapy.
Fenbendazole acts as a moderate microtubule-destabilizing agent and causes cancer cell death by modulating multiple cellular pathways.
Mebendazole has shown promise in halting the division of cells across various cancer cell lines, including glioblastoma, melanoma, colon cancer, non-small cell lung cancer, and leukemia. Research shows that mebendazole affects other cancer-related processes, such as angiogenesis, which forms the blood vessels that allow cancers to grow. Mebendazole also shows less toxicity to healthy tissue than existing chemotherapies. Some research demonstrated that treating cancer with mebendazole makes cancer cells more sensitive to radiation or chemotherapies, increasing the effectiveness of standard treatments. In low doses, mebendazole has one of the most favorable safety profiles in modern pharmacology.
Mebendazole (methyl 5-benzoyl-1H-benzimidazol-2-yl-carbamate) was introduced in 1968 as a broad-spectrum anthelmintic active against a wide range of parasites, and was first applied to human subjects in 1971. *https://pmc.ncbi.nlm.nih.gov/articles/PMC9862092/pdf/ijms-24-01334.pdf
Meco D, Attinà G, Mastrangelo S, Navarra P, Ruggiero A. Emerging Perspectives on the Antiparasitic Mebendazole as a Repurposed Drug for the Treatment of Brain Cancers. Int J Mol Sci. 2023;24(2):1334. Published 2023 Jan 10. doi:10.3390/ijms24021334
Dr. Mukhopadhyay at MD Anderson first demonstrated that mebendazole has potent anticancer activity in lab experiments in 2002.
Mebendazole and fenbendazole disrupt the parasites’ ability to absorb glucose (food). Without this regular diet, the parasites or worms quickly die. This targeted use has low toxicity and few side effects. Parasitic worms and many forms of cancer have similar biological structures. Some argue that drugs that disrupt parasites can also have the same effect on cancer cells. The same action that fenbendazole has on parasites and worms is proposed in many cancers. Cancer is not a parasite.
Fenbendazole and other benzamidazoles directly interfere with tiny structures inside cells called microtubules. This part of a cell is responsible for cell division and stability. Microtubules are a core feature of all eukaryotic cells, including those found in tumors. Fenbendazole may affect cancer cells internally. Cancer cells that are constantly growing and dividing rely on and are fed by these microtubule systems.
When the parasite can’t maintain this internal structure, it starves and dies. Some suggest this process may also apply to cancer cells.
Fenbendazole works by binding to tubulin, a protein that forms microtubules in the cells of parasites and cancer cells. This binding disrupts microtubule function, leading to the parasites’ inability to absorb nutrients and their eventual death.
Fenbendazole, an anthelmintic drug primarily used in veterinary medicine, has shown potential as an anticancer agent in recent studies. It exhibits moderate microtubule-depolymerizing activity towards human cancer cells and demonstrates antitumor effects in vitro and in vivo. The anticancer mechanisms of fenbendazole include:
Disrupting microtubule dynamics
Activating p53, a tumor suppressor gene
Inhibiting glucose uptake and metabolism in cancer cells
Inducing oxidative stress and activating the MEK3/6-p38MAPK pathway
Causing cell cycle arrest in the G2/M phase
Fenbendazole has shown efficacy against multiple cancer types, including drug-resistant cancer cells. It appears to avoid the development of resistance, unlike traditional chemotherapy drugs, potentially allowing for long-term administration.
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