Mebendazole is a generic, inexpensive prescriiption medicine used to treat worm infections. This drug is called a spindle poison because it interrupts the formation of microtubules, cellular filaments that separate newly made DNA. Chemo drugs such as Taxol and alkylating agents are also spindle poisons, but they have toxicities that mebendazole does not have.
In the last few years, a number of studies have found that mebendazole is a powerful inducer of apoptosis in a wide variety of cancer cells, both in culture dishes and mouse models.
In the following study, half maximal cytotoxic doses of mebendazole in the range 0.1 to 0.8 microM (VERY low) killed a wide diversity of cancer cells, including lung, breast, ovary, colon and osteosarcomas. These studies were also conducted in mice. Mebendazole also inhibited angiogenesis.
Unlike microtubule disruptive drugs such as Taxol and alkylating agents, mebendazole does not harm normal cells.
The following study was published this month. It shows that mebendazole kills two different strains of chemotherapy resistant melanoma cells. One strain contained a mutant p53 protein while the other harbored a normal p53 tumor suppresor protein. Mebandazole kills the cells equally. The half maximal cytotoxic dose was 0.32 microM.
Cimetidine, the generic version of the anti-ulcer drug Tagamet, promotes the toxicity of mebendazole by inhibiting its degradation in the liver.
The average blood concentration of mebendazole after a single clinical dose is 1.67 microM. This value vastly exceeds the concentration of mebendazole needed to kill a host of different cancer cells.
Mebendazole is usually sold as a chewable tablet. When chewed and allowed to remain in the mouth for a short period, the mebendazole can enter the blood through the mucosal membranes of the mouth. Of course, it can also enter the blood via the GI tract. This drug is extremely non-toxic even in doses of 4.5 grams a day.
Microtubule inhibitors are THE target of interest for chemo drugs. In this case, a simple anti-worm drug inhibits microtubule functioning at low non-toxic concentrations. In a culture dish and in mice, mebendazole induces apoptosis in a diversity of cancer cells at extremely low concentrations.
Unfortunately, this drug will NEVER enter clinical trials as a treatment for cancer. There is no money to be made.
Fortunately, physicians can prescribe this drug for the treatment of cancer without a clinical trial. This blog and the referenced articles contain all the scientific justification that they will need.
Grouppe Kurosawa, Medicine in the Public Interest