NUTRITION, NUTRIMENTS, AND CANCER

There is evidence to prove that in the background of cachexia (often co-occurring with cancer), there is a malfunction of energy supply and storage, which lead to considerable weight loss and feeling weak. It is important to note that the decrease of food intake as a result of tumor related anorexia/cachexia does not necessarily influence the growth of the tumor; therefore, no serious diet has proved to be sensible for cancer patients. The tumor is fully capable of supplying itself with energy for its own growth by consuming the substances of the body itself. Thus, both the decrease in food uptake and the tumor’s parasite nature are responsible for the development of the anorexia/cachexia syndrome. For cancer patients, cachexia represents a predictive factor for survival. The loss of weight by 10% within 6 mo is considered to be critical (1).  Patients suffering from such weight loss responded to the treatment to much less an extent than patients with constant or growing body weight. Moreover, the nutritional status exerts deep influence on the activity of the immune system as well. During the progression of the tumor, patients differ greatly in terms of anorexia and cachexia. For 15–40% of the patients, cachexia is diagnosed at the early stage of the disease and very often in patients who have no other symptoms: just weight loss and feeling weak. The chemotherapy, due to its gastrointestinal toxicity, could contribute to the enhancement of symptoms. A survey showed that 85% of the patients at an advanced stage of the disease suffered from cachexia and anorexia, more than those suffering from pain! It is important to note that there is no positive correlation between weight loss and the size of the tumor.

 Some patients with relatively small tumors lost substantial weight, whereas others with a big tumor burden never develop cachexia (2). Finally, data are available to prove that the supply of nutriments does not foster the growth of tumor. Considering all this, it seems that a tumor can ensure its own growth in the body independently of the increase or decrease of food intake. Thus, the role of nutriments in cancer is an important issue. The provision of nutriments should start preferably before the weight loss or straight after it is recognized to avoid or delay the development of cachexia. A nutriment is not expected to suppress tumor growth or to show some other antitumor effect. However, if it does it in a proven and reproducible manner, it is a special advantage and can be of great importance. FWGE —A SPECIAL NUTRIMENT FOR CANCER PATIENTS FWGE is a chemically transformed natural complex of wheat germ molecules (not identical with wheat germ or germinated wheat), which was registered in 2002 as a special nutriment for cancer patients in Hungary. The aqueous powder contains 63.2% fermented extract of wheat germ and drying aids (35% maltodextrin and 1.8% silicon dioxide). The exact chemical composition of the extract is not entirely known. In fact, this is quite usual in the case of natural products. The manufacturing process of FWGE is standardized to 2,6-dimethoxyp-benzoquinone content (0.4 mg/g on dry matter basis), but there is no data available regarding permanent composition of other constituents in different manufacturing series. The quality of FWGE is controlled by fingerprint chromatography; each batch is compared to the original one used for experimental studies.

 The GMP manufacturing technology involves extraction of wheat germs, fermentation of the extract by Saccharomyces cervisiae,separation of the fermentation liquid, drying, and granulation. In fact, the manufacturing process is patented (International Application No.: PCT/HU1998/000077). FWGE is available in pharmacies without prescription. The effects of FWGE are manifold (3–7). On the contrary, it shows no toxicity, mutagenicity, or genotoxicity (8). Moreover, the combination of FWGE with chemotherapeutic agents did not increase the toxicity or reduce antiproliferative activity (9). The role of FWGE in cancer prevention and treatment can be discussed from several aspects. Molecular Composition of FWGE and Other Wheat Germ Derived Products Natural extracts typically contain many, often hundreds or thousands, of different molecules. This is the case of FWGE and various other wheat germ derived products. Structural studies on such complex mixtures are usually not directed to determine structure and concentration of each molecular component, as it is mostly unfeasible. There are two typical approaches for characterizing such mixtures. The first is to identify and to quantify certain molecules or molecular types in the extract. This is used when targeting given molecules of biological significance (like resveratrol in wines). The second common approach is to separate the mixture into various fractions and characterize these fractions subsequently. Separation is commonly performed using chromatography. A given fraction is characterized by its retention time, whereas the relative amount of the fractions is characterized by an intensity value (depending on the type of detection, this may be, e.g., absorption of ultraviolet light). 

The molecular composition of the individual fractions (which may still contain various molecular components) may be characterized, for example, by subsequent spectroscopic analysis. Current methodologies are often based on an on-line combination of high-performance liquid chromatography (HPLC) with mass spectrometry (HPLC-MS). This allows high separation power and gives structural information on the individual components. These techniques are described in detail in a recent book (10), and these have been used to study the molecular composition of FWGE and other wheat germ derived products. Altogether, 15 wheat germ derived samples have been studied as shown in Table 1, and three of these were different FWGE batches. Two different analytical approaches have been used, namely, 1) separation of the samples by normal-phase HPLC, followed by mass spectrometric analysis since this method is well suited to isolate the polar molecules present in FWGE ; and 2) separation of the samples by reverse-phase HPLC, followed by mass spectrometric analysis, which is well suited to isolate the apolar molecules (11). The results show that both the polar and the apolar fraction of wheat germ products consist of several hundred different molecules. As an example, the HPLC-MS chromatogram of an FWGE sample is shown in Fig. 1A. Detailed mass spectrometric analysis shows that most peaks in the chromatogram consist of several components. More significant is the comparison of the molecular composition of different wheat germ derived products. 

Chromatograms and mass spectra of various products show major differences, whereas the composition of the FWGE batches studied were comparable. For example, the chromatogram of a different wheat germ derived product (a German Weizenkeime sample) under identical conditions is shown in Fig. 1B—indicating large differences in molecular composition compared to FWGE . Characterized by retention time and mass spectra, many different components were identified and quantified. A possible illustration of the variability of the molecular composition of various wheat germ derived products is shown in Fig. 2. This shows the relative amounts of 30 characteristic molecular components identified in the 15 investigated wheat germ derived products. The results clearly show that the composition of various wheat germ derived products is significantly different. Thus, experimental data obtained by one of them is not necessarily true for the other. Bearing this in mind, the most important experimental and clinical effects of FWGE are considered. Immunological Aspects After the implantation of skin allografts into mice that had gone through thymus removal, the rejection took much shorter time in the case of mice that had been treated with FWGE than in the case of the control group without FWGE treatment (12). Since the host vs. graft reaction is primarily based on cellular immune response, all this implies an enhanced cellular immune response as a result of FWGE . This is significant because the body’s natural antitumor response is also based on the function of the cellular immune system. The primary antitumor response depends on the activity of the natural killer (NK) cells.

 The activity of these cells is enhanced by the decreased level of main histocompatibility complex class 1 (MHC-I) antigens. The presence of MHC-I antigens on the cell surface makes it possible for the immune cells to recognize a cell as “self.” MHC-I antigens can be found on the surface of every cell with a nucleus including the tumor cells. The MHC-I molecule complex contains peptide fragments of endogen proteins dissociated within the cells, which stabilize the link between the MHC-I alpha and beta microglobulin peptide chains. The recognition of the MHC + peptide by the immune cells is considered to be the basic “cognitive” movement of immune reaction. Due to FWGE treatment, the expression of MHC-I molecules has decreased 90% on the surface of Jurkat T cells and 69% on Raji Burkitt lymphatic cells (13). This considerable decrease in the level of MHC-I antigens as a result of the treatment could be the trigger of the NK cells to kill the tumor cells. Moreover, in SLE-induced mice FWGE produced a shift toward Th1 (cellular immunity) response by enhancing IL-2 and IFN cytokine production while reducing Th2 (antibody related) immune response by decreasing IL-4 and IL-10 production (14). The second important area of natural immune reaction to tumor cells is the activity of macrophages (mononuclear phagocite). Macrophages are present in every organ and tissue, and their task is phagocitoses and to produce biologically active molecules (oxygen radicals and cytokines). The most important of cytokines produced by the macrophages is the TNF-α, the main mediator of antitumor defense, which plays a significant role in local inflammations and adhesive processes. 

The TNF-α is capable of killing the tumor cells both directly (induction of apoptoses, production of oxygen radicals) and indirectly (retardation of tumor angiogenesis, increase of other antitumor reactions). In human THP-1 myeloid leukemia, FWGE —together with lipopolysaccharide and phorbol myrisil acetate—has increased the TNF-α production in a dose-related manner. The immunoglobulin-like intracellular adhesive molecule (ICAM-1, CD54) has a role in connecting cells and also in the immigration of white blood cells from the blood stream. The most important part of effective immune reaction is the transfer of immune cells to the inflamed area or to the site of the tumor. TNF-α increases the production of ICAM-1 molecules and therefore helps the lymphocytes find their “target.” FWGE by itself can increase the level of ICAM-1 molecules, and this effect is synergistic to the similar activity that of TNF-α. Therefore, FWGE increases the production of ICAM-1 and may enhance the appearance of white blood cells at the tumor site in a dual way (by itself and by increasing the TNF-α production of macrophages) (15). Induction of Apoptosis According to current views, the genetic program of a mammal cell determines the whole life cycle of the cell, including differentiation (i.e., the ability of cells to respond to specific ligands), as well as the programmed death of cells. The ligands attached to the receptors on the surface of the cell cause characteristic intracellular cascade of events on the given cell. An information flow or transfer of signals is created by the receptor-ligand link outside the cell triggering the biological effect inside the cell. Such processes of signal transduction control all the functions of the cell, its metabolism, and death. 

The specific response to any outside stimulus is all controlled by the genes of the cell. The programmed death of cells (apoptosis) requires the coordinated function of certain genes, and this is exactly how it differs from cell deaths triggered by other causes (e.g., the necrosis of a cell means the collapse of the intracellular metabolism and the disorganized function of the cell). Apoptosis results in typical morphological changes (e.g., chromatin condensation and fragmentation). When the apoptotic cell dies, it does not affect the neighboring cells (cells dying in any other way usually damage the neighboring cells as well). In some tumors, spontaneous apoptosis can be noted, but it can be induced by chemotherapy, radiation therapy, or immune therapy. Therefore, the antitumor therapy can induce apoptosis of cancer cells, killing the tumor without destroying or damaging the neighboring cells. FWGE -induced apoptosis in several human cell lines including MCF-7 breast cancer (16), Jurkat acute lymphoid leukemia T cell (17,18), A2058 human melanoma (19), HT-29 colon cancer (20), HL-60 promyelocytic leukemia (21), H9 human lymphoid cell (22), and gastric cancer cell lines (23). The CD45 is a strongly glycolized receptor that is expressed to a large extent on the surface of the leukocytes and has intracellular phosphatase activity. CD45 has a fundamental role in the intracellular signal transduction of the leukocytes including the apoptosis. FWGE can decrease the CD45 phosphatase activity in Jurkat-T cell lines. FWGE , however, can induce apoptosis in cells that lack in CD45 to the same extent as the parent cell lines. This proves that the apoptosis induction by FWGE does not involve the CD45 system (17).

 Recent data show that FWGE induces apoptosis of the cells involving the caspase system (18). It is of importance that the induction of apoptosis by FWGE seems to be tumor specific, since in the case of normal peripheral blood mononuclear (PBM) cells, apoptosis does not occur as proven by DNA and FACS analyses. On the other hand FWGE inhibits in dose-related manner the polyclonal mitogen (phytohemagglutinin) induced PBM cell proliferation. This serves as evidence that FWGE -induced inhibition of cell proliferation and the induction of apoptosis have different mechanisms. FWGE was examined in Jurkat cell lines also with regard to intracellular calcium concentration. As a result of FWGE treatment, an early and transient increase in intracellular calcium concentration occurs. This observation can be explained by the enhanced influx of extracellular calcium into the cells, since in the presence of calcium chelator EGTA FWGE does not alter the intracellular calcium concentration. It is of interest that the FWGE -induced increase of intracellular calcium concentration precedes both the reduction of expression of the MHC-I molecules and the induction of apoptosis (17). Glucose Metabolism The genetic program also determines the metabolic capacity of a cell and also its unique characteristics (metabolic profile), as all this depends on the differentiation of the cell. The knowledge of the metabolic profile of cells and the analysis of the changes induced by certain stimuli become the basis for pharmaceutical research and development. The investigation of the metabolic profile of normal and tumor cells and the measurement of the metabolic changes have contributed significantly to the discovery of unknown therapeutic targets as well as to the development of new antitumor agents. 

The metabolic profile of the FWGE treated and untreated pancreatic adenocarcinoma cell lines was investigated and compared to each other in MIA cell line (24). Cells were incubated with C13 isotopic labeled glucose, and the intracellular sugar metabolism was followed. Since the carbon atoms of sugar are used in the synthesis of different types of molecules (such as ribose, fatty acids, etc.), the measurement of the amount of isotopic labeled molecules (by gas chromatography and mass spectrometry) provide a method for exact follow-up of the glucose metabolism pathways. The results of these measurements were very noteworthy. FWGE inhibited the glucose uptake of the cancer cells in a dose-related fashion as well as influenced the metabolic pathways of glucose. Namely, FWGE decreased the messenger and ribosomal RNA synthesis and at the same time enhanced the pentose cycle and fatty acid synthesis. The tumor cells primarily need sugar as the source of energy for cell division; therefore, FWGE can reduce the proliferation activity of the cancer cells by reducing the sugar uptake. To maintain the cell functions, the cells require continuous protein synthesis, which is mediated by messenger and ribosomal RNA synthesis. By reducing the available sugar for the synthesis of these nucleic acids (the intracellular sugar is redirected to the enhanced pentose cycle and fatty acid synthesis), FWGE can deeply influence the intracellular metabolism of tumor cells. In other words, FWGE can “pinch” the sugar from the nucleic acid synthesis, leading to reduced chances for survival of the tumor cells. These are direct effects of FWGE on cancer cells and do not require the contribution of the immune system.