Lycopene's anti-cancer effects.

Lycopene is a carotenoid in as a natural pigment used in food industry. Flora in the distribution of its scope is broad, mainly in tomatoes, watermelon, grapefruit and papaya, and other food. Now a lot of epidemiological and clinical studies show that the ingestion of tomato products can reduce the risk of cancer, especially gastrointestinal and prostate cancer, lycopene and tomato products are the major carotenoids.
The human body can not on its own synthesis of lycopene, vegetables and fruit must be obtained. Lycopene absorption by many factors, the proteins in food - carotene complex, large quantities of soluble dietary fiber (if plastic), the combination of cholesterol and resin, iron, zinc and protein, and gastro-intestinal diseases, allergic Reaction or parasites are likely to interfere with the absorption of lycopene. Study found that plasma levels of lycopene no gender differences, smoking and drinking on blood levels of lycopene are very small. With the increase of age, blood levels of lycopene in the fall. Lycopene in the heat processed and the presence of lipid can improve bioavailability. If the intake of unprocessed tomato juice, serum lycopene levels did not change, given the processed tomato juice, serum lycopene levels increased three times, its causes may be heat processing to rupture the cell wall, or hot tomato processing so that Red-better access to oil carriers. Also found that fat substitute for sucrose polyester serum lycopene can reduce the level of 50 percent, food mixed into the lycopene than fresh lycopene into a single crystal of serum lycopene levels increased much more. The body was found that lycopene and β-carotene crystals mixed into the food consumption than lycopene alone at the level of lycopene in the blood increased much, but β-carotene had no effect. High-dose Although β-carotene can increase the absorption of lycopene, but can also interfere with lycopene in LDL on the transport.
To complete absorption of lycopene, can also be detected in human serum lycopene to some of the oxidation products. Lycopene is the main organization of carotenoids, human testis and the highest level in the adrenal gland. In human plasma, the lycopene in the blood of the total carotenoids 21% to 43% in the prostate tissue of 64%. Study found that lycopene intake of 55 per cent of the droppings can be detected.
Epidemiological studies
1 serum concentrations of lycopene and digestive tract cancer risk of a negative correlation
In 1985 to 1991, the Italian researchers used a series of cases - control study was observed to eat tomatoes the way large intake of lycopene's role in the prevention of gastrointestinal cancer. Case study groups including the Organization confirmed the oral cancer, pharyngeal cancer, esophageal cancer, stomach, colon and rectal cancer patients, the control group without the cancer patients, ruled out the age, sex, and other mixed factors, found that high tomato red The above-intake and decreased risk of cancer-related sites, stomach, colon and rectal cancer have dropped very significantly (P <0.001) [10].
Japan four different areas of gastric cancer incidence rate has conducted a cross-sectional study, the crowd observed a randomly selected sample of gastric cancer and mortality may be related to lifestyle factors, measured in plasma vitamin A, C, E, β-carrot - And lycopene, found that only plasma lycopene and gastric cancer was negatively correlated [11].
2 intake of tomato products and prostate cancer risk of a negative correlation
Western countries prostate cancer is the common disease in elderly men. Since 1976 from 14 to 000 men for six years of follow-up study found that weekly consumption of tomatoes, five times more than the risk of prostate cancer decreased significantly.
Giovannucci from 1986 to 1992 in the United States 48,000 medical staff of the follow-up study also confirmed that can provide a lot of tomato products lycopene intake and the risk of prostate cancer were negatively correlated, in the risk of prostate cancer decreased 21 %, While other carotenoids, such as β-and α-carotene, lutein and β-hidden Huang quality and risk of prostate cancer are not relevant. The survey found that the intake of tomato sauce and prostate cancer risk of a very significant negative correlation (to reduce the maximum 34 per cent), followed by tomatoes and pizza, tomato juice is not associated with prostate cancer, may be unprocessed tomato juice In the bioavailability of lycopene too low. Control of the age, drinking smoking, body mass index and the vas deferens with mixed factors such as possible after the still negative correlation. In addition, the lycopene found in advanced prostate cancer and invasive more significant role (RR = 0.47).
3 serum levels of lycopene and other related cancer risk
The recent diagnosis of pancreatic cancer patients 12 years ago, the frozen storage of serum samples were analyzed, and the control of matching donors with serum samples were compared, found in the blood lycopene levels and the incidence of pancreatic cancer was negatively correlated. On the study found that black women, cervical cancer and lycopene is a strong negative correlation between the only carotenoids and lycopene intake and serum concentrations of lycopene showed a negative correlation. However, lycopene and the risk of lung cancer are not relevant, in Finland also found that breast cancer risk and diet or serum levels of lycopene are not relevant.
Lycopene anti-cancer mechanisms of molecular biology
1 lycopene antioxidant activity
Oxygen free radicals produced within the organization, and the body to DNA, proteins, carbohydrates and lipids, and other important macromolecules response, damage their function, raises a number of diseases such as cancer, cardiovascular diseases and aging, tomato Red-quenching singlet oxygen can be (1 O2) and the removal of hydrogen peroxide, and so on.
Lycopene can accept different excited state of the electronic energy, the role of singlet oxygen can make the energy transfer to lycopene, the generation of oxygen molecules and triplet state of lycopene (1 O2 + lycopene → 3 O2 +3 lycopene), the triplet state Lycopene (3 lycopene) and solvent through a series of optical rotation and vibration reaction regeneration. Thus, a lycopene elements can remove thousands of singlet oxygen. Carotenoids of quenching it with the capacity and the number of the double bonds, lycopene is quenching singlet oxygen and removal of hydrogen peroxide and other free radicals most capable of carotenoids, inhibit destruction of singlet oxygen capacity is β -- Carotene 2 times, some people think that this increase in capacity and the other two did not combine the button on. Lycopene can quenching singlet oxygen to prevent lipid peroxidation, protection against free radical damage biofilm [20].
2-induced cell communication gap junction
Cell space is connected by 15 ~ 20 A distance of two adjacent cells on the connection of the two (connexon) assembly from the film channel, is the main component of its chemical and biological molecular weight of 28 kD of the membrane protein. Each connector of the six dumbbell-shaped protein subunit composition, the center is the diameter of about 15 A water channel, it allows the molecular weight of 1 000 ~ 1 600D following through small molecules or ions, such as Ca2 +, 1,4 , 5 - three phosphatidylinositol, NO, cAMP, and other second messengers and growth regulators, thus ensuring the normal cell growth control signal transmission. Cell gap junction communication (GJIC) cells that can be transmitted within groups of signal control, regulating the normal cell differentiation and proliferation. Most of the tumor cells of gap junction communication weak or missing, the cells transformed into cells after their gap junction communication function or inhibition, cell gap junction communication functions of inhibiting or destroyed was considered promote cancerous stage of the important mechanisms.
Lycopene may be carcinogenic chemical agents and radiation-induced MCA mouse embryonic fibroblasts (C3H10T1 / 2) inhibit the conversion of cells. Lycopene normal cells can be enhanced between the GJIC, Japanese scholars in the rat liver tissue on the fluorescent dye tracer technology research GJIC lycopene on the role and found that when fed daily 5 mg / kg BW of lycopene for five consecutive Day, can significantly enhance the GJIC function, and 50 mg / kg BW has shown inhibition. Bertram, and so the experiments showed that lycopene can enhance the GJIC tumor cells in vitro and can inhibit the normal range of human and animal cells to the tumor transforming, molecular testing found that the level of lycopene and other carotenoids handling of the encoding connexin protein CX - 43 control gene CX-43 mRNA increased significantly, the CX-43 membrane proteins form the GJ volume increased significantly, and with the CX-43 protein phosphorylation, fluorescence detection probe found that cell GJIC functional recovery, suggesting that carotenoids May be activated by CX-43mRNA, increase the number of CX-43 protein to control GJIC function.
3 regulation of tumor cell proliferation
Lycopene may affect breast, lung and uterine cancer cell cycle S phase, suggesting that lycopene by inhibiting cell cycle in G1 to S phase of the conversion to influence cell growth.
In the last six to eight people to realize lycopene may be a useful carotenoids, people have realized that fruits and vegetables in a series of interaction and complementarity of human factors in the reduction of cancer risk in playing an important role, tomatoes Red-promising of which may be a factor.