Immune System


EFFICACY OF A MEDICAL NUTRIMENT IN THE TREATMENT OF CANCER

TARGET AUDIENCE This activity is designed to meet the educational needs of physicians and other healthcare professionals who diagnose, treat and manage patients who have or are at risk for cancer. OBJECTIVES Upon completion of this article, participants should be able to: 1. Define FWGE and discuss its safety profile. 2. Describe the mechanisms by which FWGE exerts its anticancer activity. 3. Review the efficacy of FWGE in cancer prevention and therapy, both in animal models and human clinical trials. (Altern Ther Health Med. 2007;13(2)56-63.) DISCLOSURE InnoVision Comunications assesses conflict of interest with its faculty, planners, and manager of CME activities. Conflicts of interest that are identified are thoroughly vetted by the CME committee for fair balance, scientific objectivity of studies utilized in this activity, and patient care recommendations. InnoVision is committed to providing its learners with highquality, unbiased, and state-of-the-art education. Gary L. Johanning, PhD, and Feng Wang-Johanning, MD, PhD, have no real or apparent conflicts of interest to report.T he American Cancer Society estimated in 2006 that more than 2.4 million new cancer cases, including basal and squamous cell skin cancers, would be diagnosed in the United States that year.1

TARGET AUDIENCE This activity is designed to meet the educational needs of physicians and other healthcare professionals who diagnose, treat and manage patients who have or are at risk for cancer. OBJECTIVES Upon completion of this article, participants should be able to: 1. Define FWGE and discuss its safety profile. 2. Describe the mechanisms by which FWGE exerts its anticancer activity. 3. Review the efficacy of FWGE in cancer prevention and therapy, both in animal models and human clinical trials. (Altern Ther Health Med. 2007;13(2)56-63.) DISCLOSURE InnoVision Comunications assesses conflict of interest with its faculty, planners, and manager of CME activities. Conflicts of interest that are identified are thoroughly vetted by the CME committee for fair balance, scientific objectivity of studies utilized in this activity, and patient care recommendations. InnoVision is committed to providing its learners with highquality, unbiased, and state-of-the-art education. Gary L. Johanning, PhD, and Feng Wang-Johanning, MD, PhD, have no real or apparent conflicts of interest to report.T he American Cancer Society estimated in 2006 that more than 2.4 million new cancer cases, including basal and squamous cell skin cancers, would be diagnosed in the United States that year.1

EFFICACY OF A MEDICAL NUTRIMENT IN THE TREATMENT OF CANCER

 Cancer patients in the United States generally are treated using conventional therapy, which includes surgery, chemotherapy, radiotherapy, and newer, more targeted therapies such as immunotherapy, gene therapy, angiogenesis inhibitors and targeted therapies.2 With improved diagnosis and treatment, the 5- year survival rate of cancer patients will likely increase, and these cancer survivors will try to find treatments to prevent cancer recurrence and to advance longevity after a diagnosis of cancer. A recent study found that a large percentage of breast and prostate cancer patients use some form of complementary therapy, with vitamins being used by 63% and 37% of breast and prostate cancer patients, respectively, and diet and nutrition therapy being used by 84% and 46% of these patients.3 This study suggests that cancer patients have a strong desire to seek out alternative diet and nutritional therapies to augment their conventional cancer therapy. The challenge to physicians and healthcare providers, then, is to provide information to cancer patients about which therapies are likely to be beneficial to them in preventing recurrence of cancer and promoting their well-being. This review will critically evaluate the efficacy of a plant extract that is currently being evaluated in clinical trials for treatment of cancer patients. The product is a fermented extract of wheat germ called FWGE . This article discusses how the extract is made, whether it is safe, its mode of action, and, finally, the use of FWGE in clinical cancer trials. 

WHAT IS FWGE , AND HOW IS IT PRODUCED? 

The wheat grain kernel consists of 3 parts. The endosperm is the embryo of the kernel. It makes up 83% of the kernel and is the source of energy for new wheat plants if the kernel is planted and sprouts. It is high in starch and gluten (the protein in wheat flour), but relatively low in vitamin and mineral content. The endosperm is used to make white flour. The bran (14%) consists of the thin outer layers of the wheat kernel and contains vitamins, minerals, and fiber. The germ makes up only 2%-3% of the wheat kernel and is the most nutritious part of the wheat kernel. Nutrients are concentrated in the germ, and it is rich in vitamins, minerals, proteins, and fats. Wheat germ contains high levels of tocopherol and B vitamins. It is separated from the other wheat components by the milling process. Whole-wheat flours are made by milling the whole kernel; that is, all 3 of the above parts of the wheat kernel. In addition to the nutrients listed above, wheat germ can be subjected to fermentation with Saccharomyces cerevisiae (yeast) to yield the benzoquinones 2,6-dimethoxy-benzoquinone (DMBQ ) and 2-methoxy-benzoquinone.4 These benzoquinones are present in unfermented wheat germ as glycosides; yeast glycosidase activity present during fermentation leads to release of the benzoquinones as aglycones. FWGE is an aqueous extract of wheat germ, fermented with Saccharomyces cerevisiae for 18 hours at 30˚C.5 After fermentation, water is decanted, and the product is spray-dried, homogenized, encapsulated, and formulated. 

The wheat germ fermentation end-product, which is suitable for human consumption, is a dried extract standardized to contain methoxy-substituted benzoquinones (2-methoxy-benzoquinone and 2,6-DMBQ ) at a concentration of 0.04%. Since FWGE is a complex mixture, additional, as yet poorly characterized molecules remain in the product. Nobel laureate and Hungarian scientist Dr Albert SzentGyörgyi initially proposed the use of methoxy-substituted benzoquinones like those present in FWGE as anticancer agents. He hypothesized that disorders of metabolism might play important roles in cancer development, and found that high redox potential quinones such as those discussed above could block cell replication6 and suggested that they might prove to be useful in reversing disorders of cellular metabolism. FWGE was developed by the Hungarian biochemist Máté Hidvégi and was registered in Hungary as medical nutriment no. 503 in 2002. It is approved there as a non-prescription medical nutriment for cancer patients. FWGE also has been registered as a special nutriment for cancer patients in the Czech Republic and Bulgaria and is on the Australian register of Therapeutic Goods. It is currently available in 10 countries. In the United States and a number of other countries, FWGE is classified as a dietary supplement. It is manufactured in a Good Manufacturing Practices (GMP) facility by Biromedicina First Hungarian Corporation for Cancer Research and Oncology in Budapest and is distributed in the United States as Avé, a dietary supplement instant-drink mix. IS FWGE SAFE TO CONSUME? Several studies have been carried out to evaluate the safety of FWGE in doses used for treatment of cancer and autoimmune diseases.

 Boros et al discussed some of the studies in animals and humans that provide an indication of its safety;7 studies in these species to date suggest few adverse effects of FWGE . Acute and subacute toxicology tests carried out in a Good Laboratory Practice (GLP) setting revealed minimal side effects. Toxicity studies in the rat and mouse demonstrated an acute oral LD50 of FWGE in male and female mice and rats of greater than 2,000 mg/kg. The no-observable adverse effect level, which is the greatest concentration or amount of FWGE that causes no detectable adverse alteration, was 2,000 mg/kg/day in rats, and in a subchronic study with mice and rats was found to be 3,000 mg/kg/day. There is a wide therapeutic window for FWGE . Doses toxic to normal cells are more than 50 times higher than the dosage recommended for therapy, which suggests that a wide range of therapeutic dosages can be tested before the product becomes toxic. The US Food and Drug Administration recently granted FWGE a status of Generally Recognized As Safe (GRAS), which allows it to be used in foods, drinks, and dietary supplements. Significant side effects have not been reported, but mild and transient diarrhea, nausea, flatulence, soft stool, constipation, dizziness, and increase in body weight can accompany the consumption of FWGE .

 Hematologic evaluations of hospitalized cancer patients in Hungary found that the white blood cell count, lymphocyte count, neutrophil granulocyte count, monocyte count, eosinophil granulocyte count, hemoglobin level, red blood cell count, erythrocyte sedimentation rate, hematocrit, platelet count, and prothrombin level were normal after 1-5 years of FWGE treatment.7 MECHANISM OF ACTION OF FWGE Since FWGE is a plant extract, the exact chemical composition is not known, and the constituent(s) that is active against cancer has not yet been identified. The methoxy-substituted benzoquinones are good candidates for the active ingredients in FWGE , but studies have shown that these may not be the important compounds in FWGE possessing immunostimulatory activity. As discussed in more detail in the “Immunomodulation”section of this article, FWGE in mice shortened the survival time of skin grafts in comparison to controls. However, DMBQ given in a dose equivalent to the lower FWGE dose did not have any effect on skin grafts whereas a DMBQ dose equivalent to the higher dose of FWGE actually elongated the graft survival. In addition, the higher DMBQ dose was toxic and resulted in the death of 5 experimental animals during the study.8 FWGE has documented anticancer activities, which will be discussed in the next section. Many cancer patients are using FWGE as a cancer treatment, so it is important to understand its mode of action, both from the standpoint of providing an explanation for any untoward effects that might develop with its use, as well as to identify potential novel pathways that lead to beneficial effects in cancer patients. 

What are some of the potential mechanisms that modulate the anticancer effects of FWGE ? The molecular targets of FWGE , discussed below, include apoptosis induction via poly (ADP-ribose) polymerase (PARP) and other pathways, the immune system, major histocompatibility complex (MHC) class I, ribonucleotide reductase (RNR), cyclooxygenase (COX-1 and COX-2) enzyme activity, intracellular adhesion molecule (ICAM) 1, tumor necrosis factor alpha (TNF-α) production, and transketolase (TK). This is a relatively large number of molecular targets, which suggests that several as yet undefined components of FWGE may promote its antineoplastic action. The discovery of individual active compounds in FWGE should thus be pursued to find which components are responsible for each biological effect. Cell Cycle, Induction of Apoptosis and Poly Polymerase Cleavage FWGE influences apoptosis (programmed cell death) via several molecular pathways. Since apoptosis involves the killing of cancer cells, a major mechanism of FWGE action is apoptosis induction. Probably the most significant effect on apoptosis is cleavage of PARP. As discussed below, FWGE activates downstream caspase-3 proteases, resulting in cleavage of PARP and subsequent prevention of DNA repair in cancer cells. The cytotoxic effects of FWGE have been documented in several studies, and cell death generally occurred by apoptosis and in some cases, necrosis. FWGE treatment decreased the number of Jurkat T-cell leukemia cells that accumulated a formazan dye (MTT), and this decrease was greater at higher FWGE doses, indicating that FWGE decreases cancer cell viability.9

 Cell cycle analysis by flow cytometry after propium iodide (PI) staining revealed that cells treated with 0.7 and 1 mg/mL FWGE had an increase in the sub-G1 region of the cell cycle, which is associated with apoptosis, and a significant decrease in the S phase, and these changes became prominent at 48 and 72 hours following FWGE treatment. The effective dose of FWGE for inhibiting tumor metastasis formation in cancer patients in clinical trials is 0.5 to 1 mg/mL,10 so this dosage is physiologically relevant. FWGE caused an increase in apoptosis, as measured by flow cytometry after PI and annexin V staining, in Jurkat cells, beginning at doses of 0.5 mg/mL. Doses of 0.5 and 1 mg/mL showed a greater apoptotic response at 72 hours than at 24 hours of treatment, and doses of 5 and 10 mg/mL FWGE showed a time-independent maximal effect, with approximately 90% of cancer cells undergoing apoptosis. Laser scanning cytometry experiments showed that FWGE -treated cells had undergone apoptosis, not cell death by necrosis. The authors of this study used a caspase inhibitor to see whether the phosphatidylserine externalization characteristic of caspase action is reversed in FWGE -treated cells. Movement of phosphatidylserine from the inner to the outer plasma membrane of the cell is a characteristic that distinguishes apoptosis from necrosis. The caspase inhibitor Z-VAD.fmk did indeed block the FWGE -induced increase in apoptosis in cells treated with 1 mg/mL FWGE for 72 hours, thus demonstrating that the apoptosis resulting from FWGE treatment is due to caspase activation. 

To further investigate the involvement of caspases in FWGE action, the effect of FWGE at doses of 0.3, 0.5, and 0.7 mg/mL on cleavage of PARP was determined, and cleavage of PARP was observed at FWGE doses above 0.5 mg/mL and was especially evident at a 0.7-mg/mL FWGE concentration. PARP plays an important role in DNA repair, and its cleavage leads to DNA fragmentation, resulting in the apoptosis that accompanies FWGE treatment. Breast cancer cells also respond to FWGE by inducing apoptosis. Marcsek et al reported that viability of the breast cancer cell lines MCF-7 (estrogen receptor positive) and MDA-MB231 (estrogen receptor negative) began to decrease when the cells were treated with levels of FWGE between 0.625 and 1.25 mg/mL,11 levels roughly the same as those cytotoxic to Jurkat cells in the studies described above. Cell cycle S phase and apoptosis were determined by flow cytometry based on PI and anti-5- bromo-2’-deoxyuridine (BrdU) fluorescence. FWGE strongly enhanced apoptosis of MCF-7 cells 24 and 48 hours after treatment, and this effect on apoptosis was even greater in cells treated with a combination of FWGE and the estrogen receptor modulator tamoxifen. In contrast to what was observed with Jurkat cells, the percentage of MCF-7 cells in the S phase of the cell cycle increased after 24 hours of FWGE treatment, followed by a decrease to control levels in cells treated for 48 hours.

 Colon cancer HT-29 cells showed decreased colony formation in clonogenic assays, with an IC50 value for FWGE (concentration of FWGE that results in 50% of the colony formation observed in controls) of 0.118 mg/mL,12 which is considerably lower than the levels of 0.5 to 1 mg/mL that show clinical efficacy. When vitamin C was co-administered with FWGE , the IC50 was lowered still further, with a value of 0.075 mg/mL when 100 µM vitamin C was added. Vitamin C was used here because it was previously demonstrated that vitamin C influenced the effects of FWGE when these 2 compounds were co-administered. Similar to what was found in the studies with Jurkat cells, FWGE increased the percentage of cells in the G0-G1 phase of the cell cycle and led to an arrest of the cell cycle in the G1 phase, with a subsequent depletion of cells in the S and G2-M phases. In contrast to the effect of FWGE almost exclusively involving apoptosis in Jurkat cells, in HT-29 colon cancer cells, FWGE in concentrations of 0.8 to 3.2 mg/mL induced predominantly necrosis rather than apoptosis, although apoptosis did begin to increase at high FWGE concentrations. One important aspect of FWGE as it relates to cell death is that it does not induce apoptosis in normal cells such as peripheral blood mononuclear cells.

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