Classification
Dicholoroacetates are salts of dichloroacetic acid. Both the salt and acid are man-made chemicals. DCA is a by-product of the chlorine disinfection of water.1 2 DCA is a powder that can be made into pill form.
Dichloroacetic acid is typically manufactured for industrial purposes. Because the acid form (shown above) causes severe burns, only the salt, sodium dichloroacetate (DCA), is being studied as a possible drug.3 In the late 20th century, DCA was found to decrease high blood sugar levels in diabetics.4 DCA blocks a key enzymeA protein that speeds up the process of chemical reactions in the body without becoming altered in the process. Almost every biological process is driven by the activity of enzymes. Without enzyme catalysts, the complex reactions that build and break down cell parts would not happen at a rate compatible with life. Enzyme names usually describe the reaction that is being catalyzed and all of them end in -ase. (pyruvate dehydrogenase kinaseAn enzyme that adds phosphate groups to another molecule. Many key proteins controlling gene expression are kinase targets. Addition of a phosphate group to a protein can alter the activity of the protein and are often used as molecular on/off switches. For example, the retinoblastoma tumor suppressor gene is 'off' when phosphate groups are added to the protein at specific locations. Removal of the phosphate groups turns the protein 'on'. Enzymes that remove phosphate groups are known as phosphatases. Note that all enzymes, regardless of function, end in ASE) in the metabolic pathway that produces usable energy from sugar.5
Scientific Research
DCA and metabolic disorders
Because of its effects on how sugar is used by the body, DCA has been/is being studied as a possible treatment for some metabolic diseases, including lactic acidosis.6 7 8
DCA and cancer treatment
DCA's effects on energy production pathways led to studies examining the effects of DCA on cancer cells in animals and people (in vivo) and in the laboratory (in vitroFrom the Latin, ). The work has focused on the chemical's ability to block an abnormal metabolic process that occurs in many cancer cells (called aerobic glycolysis or the "Warburg effect") and to "reactivate" nonfunctional mitochondria Mitochondria are subcellular organelles responsible for extracting the bulk of the energy we use from the food we eat. As a byproduct, oxygen radicals (reactive chemicals) are produced that may contribute to cancer formation by damaging DNA. A mitochondrion (the singular version of the word) is filled with inner membranes upon which the last stages of energy generation take place..9 10 11 12 13 Studies suggest that DCA-mediated changes lead to reduced blood vessel development (angiogenesisThe formation of blood vessels. This process is required for a tumor to grow past a small size since the blood delivers nutrients to the cells in the tumor mass.) in tumors.10 14
DCA's anti-cancer activity has been studied with cells (and a few patients) from a number of cancer types, including lung carcinoid,15 breast cancer,16 neuroblastoma,17 prostate cancer,18 multiple myeloma,19 kidney cancer,20 and endometrialRefers to the endometrium, the inner lining of the uterus. The endometrium is a common site of cancer. cancer.21 It seems to exert potent anti-cancer effects especially in conjunction with Metformin.22 23
DCA may even be used in combination with standard treatments. Research suggests that it can increase the effectiveness of radiation on cancer cells,24 decrease the side effects associated with chemotherapyTreatment of cancer patients with anticancer drugs. Commonly called 'chemo'. These drugs work by attacking cell growth or division. Often these agents are used in combination to take advantage of their different modes of attack on cell division.,25 and prevent cancer from recurring after surgery.26
Cancer cells from different types of cancer (i.e. breast vs lung vs liver) and even those from the same patient can be very different from each other. Research with neuroblastoma suggests that the differences seen between cancer cells can affect the effectiveness of DCA. As an example, the chemical has greater effects on undifferentiated, fully proliferating, more malignant neuroblastoma cancer cells than on differentiated and less malignant cells of the same type.27
However, in some systems DCA has been shown to PROTECT cancer cells from death. In research with colon cancer cells, DCA prevented the death of the cells in the laboratory and in animals.28 In mice with neuroblastoma, DCA enhanced the growth of tumor cells.29 Another study showed mixed results: DCA did not slow down tumor growth in mice, though it did make it harder for cancerous cells to spread (metastasizeThe movement of a cancer to a location outside its site of origin. The distant growths are termed metastases.).30
DCA and the immune system
The effects of DCA on the immune system are being studied and are not yet clear. One study suggests that DCA may decrease the immune response against cancer by altering the activity of T lymphocytes, while other research has shown that DCA could increase immune function in tumors by reducing lactic acid levels in the tumor environment.31 32
Clinical Trials
Despite the research done so far, relatively little is known about DCA as a cancer treatment in patients. A Canadian trial on 5 glioblastoma patients demonstrated some responses, but the information is difficult to interpret because the patients were also given other treatments and/or had failed previous treatments.33 There is a single report of a patient with non-Hodgkin's lymphomaA cancer arising in the lymphatic system. The white blood cells affected are part of the body's immune system. The lymphatic system is a large network of vessels that carry fluid and cells of the immune system around the body. Lymph nodes are regional collection centers in the lymphatic system. See also, 'lymphatic system'. who entered remissionA period of time in which the symptoms and signs of cancer are decreased or absent. Remission can be spontaneous or brought about by treatments. This may be of varying duration and does not necessarily indicate that a patient is cured. after treatment with DCA (after failing to respond to treatment with chemotherapy).34 Currently, there are several active clinical trials examining the effects of DCA on different cancer types. Some Phase I trials are complete, but study results have not been posted.35
View DCA clinical trials for cancer.
Side effects of DCA
A potentially dangerous side effect of DCA treatment is nerve damage (peripheral neuropathy). The mechanisms by which DCA induces peripheral neuropathy are not completely known, but DCA-induced neuropathy often limits the use of DCA in the treatment of patients.33 36
DCA as a potential cancer causing agent (carcinogenAn agent that is able to cause cancer. Many carcinogens are chemicals that cause changes (mutations) in DNA. Radiation is another type of carcinogen. )
According to the U.S. Environmental Protection Agency (EPA), DCA is carcinogenic in laboratory mice and rats. Several studies have shown that DCA causes cancer in lab animals.37 38 39 There have not been enough studies to determine whether DCA causes cancer in humans, but based on the results in animals, the EPA considers it ‘likely’ that DCA can cause cancer in humans.40
US Food and Drug Administration Approval
There is not enough evidence that dichloroacetate is effective in the fight against cancer, and it has not been approved by the FDA for cancer treatment.
Please be sure to see our notice on complementary therapies. To better understand and evaluate the research described above, read our Introduction to Scientific Research.
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