Coenzyme Q₁₀ was first isolated in 1957, Reviewed in [1] and its chemical structure (benzoquinone compound) was determined in 1958. Reviewed in [2] Interest in coenzyme Q₁₀ as a therapeutic agent in cancer began in 1961, when a deficiency was noted in the blood of both Swedish and American cancer patients, especially in the blood of patients with breast cancer.[2] Reviewed in [3,4] A subsequent study showed a statistically significant relationship between the level of plasma coenzyme Q₁₀ deficiency and breast cancer prognosis.[5] Low blood levels of this compound have been reported in patients with malignancies other than breast cancer, including myeloma, lymphoma, and cancers of the lung, prostate, pancreas, colon, kidney, and head and neck.[2,6] Reviewed in [7] Furthermore, decreased levels of coenzyme Q₁₀ have been detected in malignant human tissue,[8-12] but increased levels have been reported as well.[8]

A large amount of laboratory and animal data on coenzyme Q₁₀ has accumulated since 1962. Reviewed in [2] Research into cellular energy-producing mechanisms that involve this compound was awarded the Nobel Prize in chemistry in 1978. Some of the accumulated data show that coenzyme Q₁₀ stimulates animal immune systems, leading to higher antibody levels,[13] greater numbers and/or activities of macrophages and T cells (T lymphocytes),[13,14] and increased resistance to infection.[15-17] Coenzyme Q₁₀ has also been reported to increase IgG (immunoglobulin G) antibody levels and to increase the CD4 to CD8 T-cell ratio in humans.[18-20] CD4 and CD8 are proteins found on the surface of T cells, with CD4 and CD8 identifying helper T cells and cytotoxic T cells, respectively; decreased CD4 to CD8 T-cell ratios have been reported for cancer patients.[21,22] Research subsequently delineated the antioxidant properties of coenzyme Q₁₀.[23,24] Reviewed in[25-27]

Proposed mechanisms of action for coenzyme Q₁₀ that are relevant to cancer include its essential function in cellular energy production and its stimulation of the immune system (which may both be related), as well as its role as an antioxidant. Coenzyme Q₁₀ is essential to aerobic energy production, Reviewed in [1,25,28] and it has been suggested that increased cellular energy leads to increased antibody synthesis in B cells (B lymphocytes).[6,18] As noted previously (General Information section ¹), coenzyme Q₁₀ can also behave as an antioxidant. Reviewed in [1,25-27,29-32] In this capacity, coenzyme Q₁₀ is thought to stabilize cell membranes (lipid -containing structures essential to maintaining cell integrity) and to prevent free radical damage to other important cellular components. Reviewed in [1,25,27,32] Free radical damage to DNA (and possibly to other cellular molecules) may be a factor in cancer development. Reviewed in [11,23,30,33-36]

References

1. Pepping J: Coenzyme Q10. Am J Health Syst Pharm 56 (6): 519-21, 1999.  [PUBMED Abstract]
   
   
2. Folkers K, Osterborg A, Nylander M, et al.: Activities of vitamin Q10 in animal models and a serious deficiency in patients with cancer. Biochem Biophys Res Commun 234 (2): 296-9, 1997.  [PUBMED Abstract]
   
   
3. Lockwood K, Moesgaard S, Yamamoto T, et al.: Progress on therapy of breast cancer with vitamin Q10 and the regression of metastases. Biochem Biophys Res Commun 212 (1): 172-7, 1995.  [PUBMED Abstract]
   
   
4. Ren S, Lien EJ: Natural products and their derivatives as cancer chemopreventive agents. Prog Drug Res 48: 147-71, 1997.  [PUBMED Abstract]
   
   
5. Jolliet P, Simon N, Barré J, et al.: Plasma coenzyme Q10 concentrations in breast cancer: prognosis and therapeutic consequences. Int J Clin Pharmacol Ther 36 (9): 506-9, 1998.  [PUBMED Abstract]
   
   
6. Folkers K: The potential of coenzyme Q 10 (NSC-140865) in cancer treatment. Cancer Chemother Rep 2 4 (4): 19-22, 1974.  [PUBMED Abstract]
   
   
7. Folkers K: Relevance of the biosynthesis of coenzyme Q10 and of the four bases of DNA as a rationale for the molecular causes of cancer and a therapy. Biochem Biophys Res Commun 224 (2): 358-61, 1996.  [PUBMED Abstract]
   
   
8. Chipperfield B: Ubiquinone concentrations in some tumour-bearing tissues. Ubiquinone concentrations in tumours and some normal tissues in man. Nature 209 (29): 1207-8, 1966.  [PUBMED Abstract]
   
   
9. Eggens I, Elmberger PG, Löw P: Polyisoprenoid, cholesterol and ubiquinone levels in human hepatocellular carcinomas. Br J Exp Pathol 70 (1): 83-92, 1989.  [PUBMED Abstract]
   
   
10. Mano T, Iwase K, Hayashi R, et al.: Vitamin E and coenzyme Q concentrations in the thyroid tissues of patients with various thyroid disorders. Am J Med Sci 315 (4): 230-2, 1998.  [PUBMED Abstract]
    
    
11. Picardo M, Grammatico P, Roccella F, et al.: Imbalance in the antioxidant pool in melanoma cells and normal melanocytes from patients with melanoma. J Invest Dermatol 107 (3): 322-6, 1996.  [PUBMED Abstract]
    
    
12. Portakal O, Ozkaya O, Erden Inal M, et al.: Coenzyme Q10 concentrations and antioxidant status in tissues of breast cancer patients. Clin Biochem 33 (4): 279-84, 2000.  [PUBMED Abstract]
    
    
13. Bliznakov E, Casey A, Premuzic E: Coenzymes Q: stimulants of the phagocytic activity in rats and immune response in mice. Experientia 26 (9): 953-4, 1970.  [PUBMED Abstract]
    
    
14. Kawase I, Niitani H, Saijo N, et al.: Enhancing effect of coenzyme, Q10 on immunorestoration with Mycobacterium bovis BCG in tumor-bearing mice. Gann 69 (4): 493-7, 1978.  [PUBMED Abstract]
    
    
15. Bliznakov EG: Effect of stimulation of the host defense system by coenzyme Q 10 on dibenzpyrene-induced tumors and infection with Friend leukemia virus in mice. Proc Natl Acad Sci U S A 70 (2): 390-4, 1973.  [PUBMED Abstract]
    
    
16. Bliznakov EG, Adler AD: Nonlinear response of the reticuloendothelial system upon stimulation. Pathol Microbiol (Basel) 38 (6): 393-410, 1972.  [PUBMED Abstract]
    
    
17. Bliznakov EG: Coenzyme Q in experimental infections and neoplasia. In: Folkers K, Yamamura Y, eds.: Biomedical and Clinical Aspects of Coenzyme Q. Vol 1. Amsterdam, The Netherlands: Elsevier/North-Holland Biomedical Press, 1977, pp 73-83. 
    
    
18. Folkers K, Shizukuishi S, Takemura K, et al.: Increase in levels of IgG in serum of patients treated with coenzyme Q10. Res Commun Chem Pathol Pharmacol 38 (2): 335-8, 1982.  [PUBMED Abstract]
    
    
19. Folkers K, Hanioka T, Xia LJ, et al.: Coenzyme Q10 increases T4/T8 ratios of lymphocytes in ordinary subjects and relevance to patients having the AIDS related complex. Biochem Biophys Res Commun 176 (2): 786-91, 1991.  [PUBMED Abstract]
    
    
20. Barbieri B, Lund B, Lundström B, et al.: Coenzyme Q10 administration increases antibody titer in hepatitis B vaccinated volunteers--a single blind placebo-controlled and randomized clinical study. Biofactors 9 (2-4): 351-7, 1999.  [PUBMED Abstract]
    
    
21. Shaw M, Ray P, Rubenstein M, et al.: Lymphocyte subsets in urologic cancer patients. Urol Res 15 (3): 181-5, 1987.  [PUBMED Abstract]
    
    
22. Tsuyuguchi I, Shiratsuchi H, Fukuoka M: T-lymphocyte subsets in primary lung cancer. Jpn J Clin Oncol 17 (1): 13-7, 1987.  [PUBMED Abstract]
    
    
23. Yamamoto Y, Yamashita S, Fujisawa A, et al.: Oxidative stress in patients with hepatitis, cirrhosis, and hepatoma evaluated by plasma antioxidants. Biochem Biophys Res Commun 247 (1): 166-70, 1998.  [PUBMED Abstract]
    
    
24. Yamamoto Y, Yamashita S: Plasma ratio of ubiquinol and ubiquinone as a marker of oxidative stress. Mol Aspects Med 18 (Suppl): S79-84, 1997.  [PUBMED Abstract]
    
    
25. Crane FL, Sun IL, Sun EE: The essential functions of coenzyme Q. Clin Investig 71 (8 Suppl): S55-9, 1993.  [PUBMED Abstract]
    
    
26. Overvad K, Diamant B, Holm L, et al.: Coenzyme Q10 in health and disease. Eur J Clin Nutr 53 (10): 764-70, 1999.  [PUBMED Abstract]
    
    
27. Ernster L, Forsmark-Andrée P: Ubiquinol: an endogenous antioxidant in aerobic organisms. Clin Investig 71 (8 Suppl): S60-5, 1993.  [PUBMED Abstract]
    
    
28. Folkers K, Wolaniuk A: Research on coenzyme Q10 in clinical medicine and in immunomodulation. Drugs Exp Clin Res 11 (8): 539-45, 1985.  [PUBMED Abstract]
    
    
29. Beyer RE, Nordenbrand K, Ernster L: The role of coenzyme Q as a mitochondrial antioxidant: a short review. In: Folkers K, Yamamura Y, eds.: Biomedical and Clinical Aspects of Coenzyme Q. Vol 5. Amsterdam, The Netherlands: Elsevier Science Publishers B V (Biomedical Division), 1986, pp 17-24. 
    
    
30. Gordon M: Dietary antioxidants in disease prevention. Nat Prod Rep 13 (4): 265-73, 1996.  [PUBMED Abstract]
    
    
31. Palazzoni G, Pucello D, Littarru GP, et al.: Coenzyme Q10 and colorectal neoplasms in aged patients. Rays 22 (1 Suppl): 73-6, 1997 Jan-Mar.  [PUBMED Abstract]
    
    
32. Ernster L, Dallner G: Biochemical, physiological and medical aspects of ubiquinone function. Biochim Biophys Acta 1271 (1): 195-204, 1995.  [PUBMED Abstract]
    
    
33. Aust AE, Eveleigh JF: Mechanisms of DNA oxidation. Proc Soc Exp Biol Med 222 (3): 246-52, 1999.  [PUBMED Abstract]
    
    
34. Halliwell B: Oxygen and nitrogen are pro-carcinogens. Damage to DNA by reactive oxygen, chlorine and nitrogen species: measurement, mechanism and the effects of nutrition. Mutat Res 443 (1-2): 37-52, 1999.  [PUBMED Abstract]
    
    
35. Burcham PC: Internal hazards: baseline DNA damage by endogenous products of normal metabolism. Mutat Res 443 (1-2): 11-36, 1999.  [PUBMED Abstract]
    
    
36. Dreher D, Junod AF: Role of oxygen free radicals in cancer development. Eur J Cancer 32A (1): 30-8, 1996.  [PUBMED Abstract]
    
    

Glossary Terms

In biochemistry, reactions that need oxygen to happen or happen when oxygen is present.

A type of protein made by plasma cells (a type of white blood cell) in response to an antigen (foreign substance). Each antibody can bind to only one specific antigen. The purpose of this binding is to help destroy the antigen. Antibodies can work in several ways, depending on the nature of the antigen. Some antibodies destroy antigens directly. Others make it easier for white blood cells to destroy the antigen.

A substance that protects cells from the damage caused by free radicals (unstable molecules made by the process of oxidation during normal metabolism). Free radicals may play a part in cancer, heart disease, stroke, and other diseases of aging. Antioxidants include beta-carotene, lycopene, vitamins A, C, and E, and other natural and manufactured substances.

A white blood cell that comes from bone marrow. As part of the immune system, B cells make antibodies and help fight infections. Also called B lymphocyte.

A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.

Cancer that forms in tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). It occurs in both men and women, although male breast cancer is rare.

A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.

A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called a clinical trial.

A substance found in most tissues in the body, and in many foods. It can also be made in the laboratory. It is used by the body to produce energy for cells, and as an antioxidant. It is being studied in the treatment of cancer and in the relief of side effects caused by some cancer treatments. Also called Q10, CoQ10, vitamin Q10, and ubiquinone.

The longest part of the large intestine, which is a tube-like organ connected to the small intestine at one end and the anus at the other. The colon removes water and some nutrients and electrolytes from partially digested food. The remaining material, solid waste called stool, moves through the colon to the rectum and leaves the body through the anus.

A type of white blood cell that can directly destroy specific cells. T cells can be separated from other blood cells, grown in the laboratory, and then given to a patient to destroy tumor cells. Certain cytokines can also be given to a patient to help form cytotoxic T cells in the patient's body.

In medicine, a shortage of a substance (such as a vitamin or mineral) needed by the body.

DNA. The molecules inside cells that carry genetic information and pass it from one generation to the next. Also called DNA.

A highly reactive chemical that often contains oxygen and is produced when molecules are split to give products that have unpaired electrons (a process called oxidation). Free radicals can damage important cellular molecules such as DNA or lipids or other parts of the cell.

Cancer that arises in the head or neck region (in the nasal cavity, sinuses, lips, mouth, salivary glands, throat, or larynx [voice box]).

The complex group of organs and cells that defends the body against infections and other diseases.

A type of protein that acts as an antibody.

Invasion and multiplication of germs in the body. Infections can occur in any part of the body and can spread throughout the body. The germs may be bacteria, viruses, yeast, or fungi. They can cause a fever and other problems, depending on where the infection occurs. When the body’s natural defense system is strong, it can often fight the germs and prevent infection. Some cancer treatments can weaken the natural defense system.

One of a pair of organs in the abdomen. Kidneys remove waste from the blood (as urine), produce erythropoietin (a substance that stimulates red blood cell production), and play a role in blood pressure regulation.

Research done in a laboratory. These studies may use test tubes or animals to find out if a drug, procedure, or treatment is likely to be useful. Laboratory studies take place before any testing is done in humans.

Fat.

One of a pair of organs in the chest that supplies the body with oxygen, and removes carbon dioxide from the body.

A type of white blood cell. Lymphocytes have a number of roles in the immune system, including the production of antibodies and other substances that fight infections and other diseases.

Cancer that begins in cells of the immune system. There are two basic categories of lymphomas. One kind is Hodgkin lymphoma, which is marked by the presence of a type of cell called the Reed-Sternberg cell. The other category is non-Hodgkin lymphomas, which includes a large, diverse group of cancers of immune system cells. Non-Hodgkin lymphomas can be further divided into cancers that have an indolent (slow-growing) course and those that have an aggressive (fast-growing) course. These subtypes behave and respond to treatment differently. Both Hodgkin and non-Hodgkin lymphomas can occur in children and adults, and prognosis and treatment depend on the stage and the type of cancer.

A type of white blood cell that surrounds and kills microorganisms, removes dead cells, and stimulates the action of other immune system cells.

A cancerous tumor that can invade and destroy nearby tissue and spread to other parts of the body.

Cancerous. Malignant tumors can invade and destroy nearby tissue and spread to other parts of the body.

The smallest particle of a substance that has all of the physical and chemical properties of that substance. Molecules are made up of one or more atoms. If they contain more than one atom, the atoms can be the same (an oxygen molecule has two oxygen atoms) or different (a water molecule has two hydrogen atoms and one oxygen atom). Biological molecules, such as proteins and DNA, can be made up of many thousands of atoms.

Cancer that arises in plasma cells, a type of white blood cell.

A glandular organ located in the abdomen. It makes pancreatic juices, which contain enzymes that aid in digestion, and it produces several hormones, including insulin. The pancreas is surrounded by the stomach, intestines, and other organs.

Research using animals to find out if a drug, procedure, or treatment is likely to be useful. Preclinical studies take place before any testing in humans is done.

The likely outcome or course of a disease; the chance of recovery or recurrence.

A gland in the male reproductive system. The prostate surrounds the part of the urethra (the tube that empties the bladder) just below the bladder, and produces a fluid that forms part of the semen.

A molecule made up of amino acids that are needed for the body to function properly. Proteins are the basis of body structures such as skin and hair and of substances such as enzymes, cytokines, and antibodies.

Describes a mathematical measure of difference between groups. The difference is said to be statistically significant if it is greater than what might be expected to happen by chance alone. Also called significant.

One type of white blood cell that attacks virus-infected cells, foreign cells, and cancer cells. T cells also produce a number of substances that regulate the immune response. Also called T lymphocyte.

Having to do with treating disease and helping healing take place.

A group or layer of cells that work together to perform a specific function.