Instruct: Given a question, retrieve relevant passages that answer the question.
Query: How can I preserve the anti-cancer effects of cooked garlic?
The aim of this study was to determine the bioavailability and kinetics of the supposed anticarcinogen sulforaphane, the hydrolysis product of glucoraphanin, from raw and cooked broccoli. Eight men consumed 200 g of crushed broccoli, raw or cooked, with a warm meal in a randomized, free-living, open cross-over trial. Higher amounts of sulforaphane were found in the blood and urine when broccoli was eaten raw (bioavailability of 37%) versus cooked (3.4%, p ) 0.002). Absorption of sulforaphane was delayed when cooked broccoli was consumed (peak plasma time ) 6 h) versus raw broccoli (1.6 h, p ) 0.001). Excretion half-lives were comparable, 2.6 and 2.4 h on average, for raw and cooked broccoli, respectively (p ) 0.5). This study gives complete kinetic data and shows that consumption of raw broccoli results in faster absorption, higher bioavailability, and higher peak plasma amounts of sulforaphane, compared to cooked broccoli.
The use of turmeric, derived from the root of the plant Curcuma longa, for treatment of different inflammatory diseases has been described in Ayurveda and in traditional Chinese medicine for thousands of years. The active component of turmeric responsible for this activity, curcumin, was identified almost two centuries ago. Modern science has revealed that curcumin mediates its effects by modulation of several important molecular targets, including transcription factors (e.g., NF-kappaB, AP-1, Egr-1, beta-catenin, and PPAR-gamma), enzymes (e.g., COX2, 5-LOX, iNOS, and hemeoxygenase-1), cell cycle proteins (e.g., cyclin D1 and p21), cytokines (e.g., TNF, IL-1, IL-6, and chemokines), receptors (e.g., EGFR and HER2), and cell surface adhesion molecules. Because it can modulate the expression of these targets, curcumin is now being used to treat cancer, arthritis, diabetes, Crohn's disease, cardiovascular diseases, osteoporosis, Alzheimer's disease, psoriasis, and other pathologies. Interestingly, 6-gingerol, a natural analog of curcumin derived from the root of ginger (Zingiber officinalis), exhibits a biologic activity profile similar to that of curcumin. The efficacy, pharmacologic safety, and cost effectiveness of curcuminoids prompt us to "get back to our roots."
The consumption of cooked meat appears to predispose individuals to colonic cancer and heterocyclic aromatic amines (HA), formed during the cooking of meat, have been suggested as aetiological agents. Consumption of cruciferous vegetables is thought to protect against cancer. To study the effect of cruciferous vegetables on heterocyclic aromatic amine metabolism in man, a three-period, dietary intervention study has been carried out with 20 non-smoking Caucasian male subjects consuming cooked meat meals containing known amounts of these carcinogens. A high cruciferous vegetable diet (250 g each of Brussels sprouts and broccoli per day) was maintained during period 2 but such vegetables were excluded from periods 1 and 3. At the end of each period, subjects consumed a cooked meat meal and urinary excretion of the HA 2-amino-3,8-dimethylimidazo(4,5-f)quinoxaline (MeIQx) and 2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine (PhIP) was measured. Following a 12 day period of cruciferous vegetable consumption (period 2), induction of hepatic CYP1A2 activity was apparent from changes in the kinetics of caffeine metabolism. Excretion of MeIQx and PhIP in urine at the end of this period of the study was reduced by 23 and 21%, respectively, compared with period 1. This reduction in excretion is probably due to an increase in amine metabolism that might be expected given the observed increase in CYP1A2 activity, since this enzyme has been shown to be primarily responsible for the oxidative activation of MeIQx and PhIP in man. In period 2, urinary mutagenicity was increased relative to period 1 by 52 and 64% in the absence and presence, respectively, of a human liver microsomal activation system, yet no evidence was found of PhIP adduction to lymphocyte DNA, a potential biomarker of the activation process. After another 12 days without cruciferous vegetables (period 3 of the study), the kinetics of caffeine metabolism had returned to original values but excretion of MeIQx and PhIP was still reduced by 17 and 30%, respectively, and urinary mutagenicity (with metabolic activation) was still elevated compared with period 1. This prolonged response of amine metabolism to the cruciferous vegetable diet, shown especially with PhIP, suggests that enzyme systems other than CYP1A2 are involved and affected by a cruciferous vegetable diet.
Cancer is a leading cause of death worldwide. There are a lot of cancer causing agents which are divided as physical carcinogens, chemical carcinogens and biological carcinogens. But most of the carcinogens or causes of cancer are related to our lifestyle like diet, habit, occupation, radiation and some infection, etc. Chemoprevention is highly necessary to prevent cancer related preterm death. For this besides avoiding the causes of cancer we should concentrate ourselves on our diet. Because, numerous phytochemicals derived from edible plants have been reported to interfere with a specific stage of the carcinogenic process. Many mechanisms have been shown to account for the anticarcinogenic actions of dietary constituents and recently attention has been focused on intracellular-signalling cascades as common molecular targets for various chemopreventive phytochemicals. In this study, we tried to describe lifestyle related causes of cancer and the molecular basis of cancer prevention through the phytochemicals.
OBJECTIVE: The aim of this work was to determine the bioavailability of herbs and spices after human consumption by measuring the ability to protect lymphocytes from an oxidative injury and by examining the impact on inflammatory biomarkers in activated THP-1 cells. METHODS: Ten to 12 subjects in each of 13 groups consumed a defined amount of herb or spice for 7 days. Blood was drawn from subjects before consumption and 1 hour after taking the final herb or spice capsules. Subject serum and various extractions of the herbs and spices were analyzed for antioxidant capacity by oxygen radical absorbance capacity (ORAC) analysis or by 1,1-diphenyl-2-picrylhydrzyl (DPPH). Subject peripheral blood mononuclear cells (PBMCs) in medium with10% autologous serum were incubated with hydrogen peroxide to induce DNA strand breaks. Subject serum was also used to treat activated THP-1 cells to determine relative quantities of 3 inflammatory cytokine (tumor necrosis factor-α [TNF-α], interleukin-1α [IL-1α], and IL-6) mRNAs. RESULTS: Herbs and spices that protected PBMCs against DNA strand breaks were paprika, rosemary, ginger, heat-treated turmeric, sage, and cumin. Paprika also appeared to protect cells from normal apoptotic processes. Of the 3 cytokine mRNAs studied (TNF-α, IL-1α, and IL-6), TNF-α was the most sensitive responder to oxidized LDL-treated macrophages. Clove, ginger, rosemary, and turmeric were able to significantly reduce oxidized LDL-induced expression of TNF-α. Serum from those consuming ginger reduced all three inflammatory biomarkers. Ginger, rosemary, and turmeric showed protective capacity by both oxidative protection and inflammation measures. CONCLUSIONS: DNA strand breaks and inflammatory biomarkers are a good functional measure of a food's bioavailability.
Legumes are the basés diet in several countries. They hold a high nutritional value, but other properties related to human health are nowadays being studied. The aim of this work was to study the influence of processes (boiling or germination) on the phenolic composition of dark beans (Phaseolus vulgaris L. c.v. Tolosana) and their effect on their antioxidant, neuroprotective and anticancer ability. Phenolic composition of raw and processed dark beans was analysed by HPLC-PAD and HPLC-ESI/MS. The antioxidant activity was evaluated by ORAC. Astrocytes cultures (U-373) have been used to test their neuroprotective effect. Anticancer activities were evaluated on three different cell lines (renal adenocarcinoma (TK-10), breast adenocarcinoma (MCF-7) and melanoma (UACC-62)) by sulphorhodamine B method. Qualitative and quantitative differences in phenolic composition have been observed between raw and processed dark beans that influence the antioxidant activity, mainly for germinated samples which show a decrease of antioxidant capacity. Although every assayed extracts decreased reactive oxygen species release and exhibited cytotoxicity activities on cancer cell lines, raw beans proved to be the most active in neuroprotective and antitumoral effects; this sample is especially rich in phenolic compounds, mainly anthocyanins. This study further demonstrated that phenolic composition of dark beans is related with cooking process and so with their neuroprotective and anticancer activity; cooking of dark beans improves their digestion and absorption at intestinal level, while maintaining its protective ability on oxidative process at cellular level. Copyright © 2012 Elsevier Ltd. All rights reserved.
Cancer is primarily a disease of old age, and that life style plays a major role in the development of most cancers is now well recognized. While plant-based formulations have been used to treat cancer for centuries, current treatments usually involve poisonous mustard gas, chemotherapy, radiation, and targeted therapies. While traditional plant-derived medicines are safe, what are the active principles in them and how do they mediate their effects against cancer is perhaps best illustrated by curcumin, a derivative of turmeric used for centuries to treat a wide variety of inflammatory conditions. Curcumin is a diferuloylmethane derived from the Indian spice, turmeric (popularly called "curry powder") that has been shown to interfere with multiple cell signaling pathways, including cell cycle (cyclin D1 and cyclin E), apoptosis (activation of caspases and down-regulation of antiapoptotic gene products), proliferation (HER-2, EGFR, and AP-1), survival (PI3K/AKT pathway), invasion (MMP-9 and adhesion molecules), angiogenesis (VEGF), metastasis (CXCR-4) and inflammation (NF-kappaB, TNF, IL-6, IL-1, COX-2, and 5-LOX). The activity of curcumin reported against leukemia and lymphoma, gastrointestinal cancers, genitourinary cancers, breast cancer, ovarian cancer, head and neck squamous cell carcinoma, lung cancer, melanoma, neurological cancers, and sarcoma reflects its ability to affect multiple targets. Thus an "old-age" disease such as cancer requires an "age-old" treatment.
Scope Anthocyanins, the natural pigments in plant foods, have been associated with cancer prevention. However, the content of anthocyanins in staple foods is typically low and the mechanisms by which they exert anti-cancer activity is not yet fully defined. Methods and results We selected an anthocyanin-enriched purple-fleshed sweet potato clone, P40, and investigated its potential anti-cancer effect in both in vitro cell culture and in vivo animal model. In addition to a high level of total phenolics and antioxidant capacity, P40 possesses a high content of anthocyanins at 7.5 mg/g dry matter. Treatment of human colonic SW480 cancer cells with P40 anthocyanin extracts at 0–40 μM of peonidin-3-glucoside equivalent resulted in a dose-dependent decrease in cell number due to cytostatic arrest of cell cycle at G1 phase but not cytotoxicity. Furthermore, dietary P40 at 10–30% significantly suppressed azoxymethane-induced formation of aberrant crypt foci in the colons of CF-1 mice in conjunction with, at least in part, a lesser proliferative PCNA and a greater apoptotic caspase-3 expression in the colon mucosal epithelial cells. Conclusion These observations, coupled with both in vitro and in vivo studies reported here, suggest anthocyanin-enriched sweet potato P40 may protect against colorectal cancer by inducing cell cycle arrest, anti-proliferative and apoptotic mechanisms.
BACKGROUND: A growing number of preclinical studies have demonstrated that curcumin could be a promising anticancer drug; however, poor bioavailability has been the major obstacle for its clinical application. To overcome this problem, we developed a new form of curcumin (Theracurmin) and reported high plasma curcumin levels could be safely achieved after a single administration of Theracurmin in healthy volunteers. In this study, we aimed to evaluate the safety of repetitive administration of Theracurmin in cancer patients. METHODS: Pancreatic or biliary tract cancer patients who failed standard chemotherapy were eligible for this study. Based on our previous pharmacokinetic study, we selected Theracurmin containing 200 mg of curcumin (Level 1) as a starting dose, and the dose was safely escalated to Level 2, which contained 400 mg of curcumin. Theracurmin was orally administered every day with standard gemcitabine-based chemotherapy. In addition to safety and pharmacokinetics data, NF-κB activity, cytokine levels, efficacy, and quality-of-life score were evaluated. RESULTS: Ten patients were assigned to level 1 and six were to level 2. Peak plasma curcumin levels (median) after Theracurmin administration were 324 ng/mL (range, 47-1,029 ng/mL) at Level 1 and 440 ng/mL (range, 179-1,380 ng/mL) at Level 2. No unexpected adverse events were observed and 3 patients safely continued Theracurmin administration for >9 months. CONCLUSIONS: Repetitive systemic exposure to high concentrations of curcumin achieved by Theracurmin did not increase the incidence of adverse events in cancer patients receiving gemcitabine-based chemotherapy.
We assessed the contribution of culinary and medicinal herbs to the total intake of dietary antioxidants. Our results demonstrate that there is more than a 1000-fold difference among antioxidant concentrations of various herbs. Of the dried culinary herbs tested, oregano, sage, peppermint, garden thyme, lemon balm, clove, allspice and cinnamon as well as the Chinese medicinal herbs Cinnamomi cortex and Scutellariae radix all contained very high concentrations of antioxidants (i.e., >75 mmol/100 g). In a normal diet, intake of herbs may therefore contribute significantly to the total intake of plant antioxidants, and be an even better source of dietary antioxidants than many other food groups such as fruits, berries, cereals and vegetables. In addition, the herbal drug, Stronger Neo-Minophagen C, a glycyrrhizin preparation used as an intravenous injection for the treatment of chronic hepatitis, boosts total antioxidant intake. It is tempting to speculate that several of the effects due to these herbs are mediated by their antioxidant activities.
Ionizing radiation of fruits and vegetables, in the form of gamma rays or electron beams, is effective in overcoming quarantine barriers in trade and prolonging shelf life, but a void of information persists on ionizing radiation effects of vitamin profiles in individual foods. Baby-leaf spinach from commercial cultivars, flat-leafed 'Lazio' and crinkled-leaf 'Samish', was grown, harvested, and surface sanitized according to industry practices. Baby-leaf spinach of each cultivar was packaged under air or N(2) atmosphere, representing industry practices, then exposed to cesium-137 gamma-radiation at 0.0, 0.5, 1.0, 1.5, or 2.0 kGy. Following irradiation, leaf tissues were assayed for vitamin (C, E, K, B(9)) and carotenoid (lutein/zeaxanthin, neoxanthin, violoxanthin, and beta-carotene) concentrations. Atmospheres by irradiation had little consistent effect, but N(2) versus air was associated with elevated dihydroascorbic acid levels. Four phytonutrients (vitamins B(9), E, and K and neoxanthin) exhibited little or no change in concentration with increasing doses of irradiation. However, total ascorbic acid (vitamin C), free ascorbic acid, lutein/zeaxanthin, violaxanthin, and beta-carotene all were significantly reduced at 2.0 kGy and, depending on cultivar, were affected at lesser doses of 0.5 and 1.5 kGy. Dihydroascorbic acid, the most affected compound and an indicator of stress, likely due to irradiation-generated oxidative radicals, increased with increasing irradiation doses >0.5 kGy.
Between 2000 and 2050, the number of new cancer patients diagnosed annually is expected to double, with an accompanying increase in treatment costs of more than $80 billion over just the next decade. Efficacious strategies for cancer prevention will therefore be vital for improving patients' quality of life and reducing healthcare costs. Judah Folkman first proposed antiangiogenesis as a strategy for preventing dormant microtumors from progressing to invasive cancer. Although antiangiogenic drugs are now available for many advanced malignancies (colorectal, lung, breast, kidney, liver, brain, thyroid, neuroendocrine, multiple myeloma, myelodysplastic syndrome), cost and toxicity considerations preclude their broad use for cancer prevention. Potent antiangiogenic molecules have now been identified in dietary sources, suggesting that a rationally designed antiangiogenic diet could provide a safe, widely available, and novel strategy for preventing cancer. This paper presents the scientific, epidemiologic, and clinical evidence supporting the role of an antiangiogenic diet for cancer prevention.
BACKGROUND: Vanillin is responsible for the flavor and smell of vanilla, a widely used flavoring agent. Previous studies showed that vanillin could enhance the repair of mutations and thus function as an anti-mutagen. However, its role in cancer, a disease that is closely related to mutation has not yet been fully elucidated. METHODS: Hence, this study investigated the cytolytic and cytostatic properties of vanillin against HT-29, a human colorectal cancer cell line. Methods used including cell viability assay, acridine orange (AO)-ethidium bromide (EB) double staining cell morphological analysis, Cell cycle analysis, annexin V-propidium iodide apoptosis test and 5-bromo-2-deoxyuridine (BrdU)-labeling cell proliferation assay. RESULTS: Results showed that apoptosis was induced by vanillin and the IC(50) for HT-29 and NIH/3T3 normal cell lines were 400 microg/ml and 1000 microg/ml, respectively. Different concentrations of vanillin arrest cell cycle at different checkpoints. 5-Bromo-2-deoxyuridine-labeling cell proliferation assay showed that G0/G1 arrest was achieved at lower concentration of vanillin (200 microg/ml) while cell cycle analysis by flow cytometer showed that G2/M arrest occurs at higher concentration of vanillin (1000 microg/ml). CONCLUSION: Cytolytic and cytostatic effects shown by vanillin showed that it could be a useful colorectal cancer preventive agent. Further in vivo study should be carried out to confirm that similar effects could happen in animals.
Berries have been recognized as a functional food with potential to protect against a variety of health conditions, including some cancers. Cranberry (Vaccinium macrocarpon) production and consumption have grown in recent years, warranting further evaluation of potential health benefits. Extracts and isolated constituents from cranberry fruit inhibit growth and proliferation of tumor cells in vitro, and recent data from animal studies lend further support to cranberry's reputation as a cancer fighter. Several likely mechanisms of action for cranberry against prostate and other cancers have been identified, including induction of apoptosis and inhibition of events linked to cellular invasion and migration. This article attempts to put into perspective what is known about cranberry's potential chemopreventive properties, what is yet to be determined, and some factors to consider as research moves forward. Copyright © 2011 Society of Chemical Industry.
Broccoli consumption may reduce the risk of various cancers and many broccoli supplements are now available. The bioavailability and excretion of the mercapturic acid pathway metabolites isothiocyanates after human consumption of broccoli supplements has not been tested. Two important isothiocyanates from broccoli are sulforaphane and erucin. We employed a cross-over study design in which 12 subjects consumed 40 grams of fresh broccoli sprouts followed by a 1 month washout period and then the same 12 subjects consumed 6 pills of a broccoli supplement. As negative controls for isothiocyanate consumption four additional subjects consumed alfalfa sprouts during the first phase and placebo pills during the second. Blood and urine samples were collected for 48 hours during each phase and analyzed for sulforaphane and erucin metabolites using LC-MS/MS. The bioavailability of sulforaphane and erucin is dramatically lower when subjects consume broccoli supplements compared to fresh broccoli sprouts. The peaks in plasma concentrations and urinary excretion were also delayed when subjects consumed the broccoli supplement. GSTP1 polymorphisms did not affect the metabolism or excretion of sulforaphane or erucin. Sulforaphane and erucin are able to interconvert in vivo and this interconversion is consistent within each subject but variable between subjects. This study confirms that consumption of broccoli supplements devoid of myrosinase activity does not produce equivalent plasma concentrations of the bioactive isothiocyanate metabolites compared to broccoli sprouts. This has implications for people who consume the recommended serving size (1 pill) of a broccoli supplement and believe they are getting equivalent doses of isothiocyanates.
Curcumin, from the curry spice turmeric, has been shown to possess potent antioxidant and antiinflammatory properties and to reduce beta-amyloid and plaque burden in experimental studies, but epidemiologic evidence is lacking. The authors investigated the association between usual curry consumption level and cognitive function in elderly Asians. In a population-based cohort (n = 1,010) of nondemented elderly Asian subjects aged 60-93 years in 2003, the authors compared Mini-Mental State Examination (MMSE) scores for three categories of regular curry consumption, taking into account known sociodemographic, health, and behavioral correlates of MMSE performance. Those who consumed curry "occasionally" and "often or very often" had significantly better MMSE scores than did subjects who "never or rarely" consumed curry. The authors reported tentative evidence of better cognitive performance from curry consumption in nondemented elderly Asians, which should be confirmed in future studies.
Phytochemicals are recognized as playing an important role in cancer prevention by fruits and vegetables. The avocado is a widely grown and consumed fruit that is high in nutrients and low in calories, sodium, and fats. Studies have shown that phytochemicals extracted from the avocado fruit selectively induce cell cycle arrest, inhibit growth, and induce apoptosis in precancerous and cancer cell lines. Our recent studies indicate that phytochemicals extracted with chloroform from avocado fruits target multiple signaling pathways and increase intracellular reactive oxygen leading to apoptosis. This review summarizes the reported phytochemicals in avocado fruit and discusses their molecular mechanisms and targets. These studies suggest that individual and combinations of phytochemicals from the avocado fruit may offer an advantageous dietary strategy in cancer prevention.
Pine needles (Pinus densiflora Siebold et Zuccarini) have long been used as a traditional health-promoting medicinal food in Korea. To investigate their potential anticancer effects, antioxidant, antimutagenic, and antitumor activities were assessed in vitro and/or in vivo. Pine needle ethanol extract (PNE) significantly inhibited Fe(2+)-induced lipid peroxidation and scavenged 1,1-diphenyl- 2-picrylhydrazyl radical in vitro. PNE markedly inhibited mutagenicity of 2-anthramine, 2-nitrofluorene, or sodium azide in Salmonella typhimurium TA98 or TA100 in Ames tests. PNE exposure effectively inhibited the growth of cancer cells (MCF-7, SNU-638, and HL-60) compared with normal cell (HDF) in 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. In in vivo antitumor studies, freeze-dried pine needle powder supplemented (5%, wt/wt) diet was fed to mice inoculated with Sarcoma-180 cells or rats treated with mammary carcinogen, 7,12-dimethylbenz[a]anthracene (DMBA, 50 mg/kg body weight). Tumorigenesis was suppressed by pine needle supplementation in the two model systems. Moreover, blood urea nitrogen and aspartate aminotransferase levels were significantly lower in pine needle-supplemented rats in the DMBA-induced mammary tumor model. These results demonstrate that pine needles exhibit strong antioxidant, antimutagenic, and antiproliferative effects on cancer cells and also antitumor effects in vivo and point to their potential usefulness in cancer prevention.
A study was performed to investigate the antimutagenic effect of broccoli flower head by the Ames Salmonella reverse mutation assay. Broccoli flower head being the most highly edible part in the plant was analysed for its antimutagenic effect. Without isolating the phytomolecules, the crude ethanol extract of broccoli flower head was tested for suppressing the mutagenic effect induced by certain chemical mutagens. Three strains - TA 98, TA102 and TA 1535 were used in the study. The tester strains were challenged with their respective mutagens. These were challenged with the ethanol extract of broccoli flower head at concentrations of 23 and 46 mg/plate. The plates were incubated for 72 h and the revertant colonies were counted. The crude extract did not prove to be promutagenic. The ethanol extract of the broccoli flower head at 46 mg/plate suppressed the mutagenic effect induced by the corresponding positive mutagens on all the three tester strains used in this study. The crude extract of broccoli flower head alone was not cytotoxic even at the maximum concentration tested (46 mg/plate). In conclusion, the ethanol extract of broccoli at 46 mg/plate suggests their diverse antimutagenic potential against the mutagenic chemicals employed in this study. (c) 2007 John Wiley & Sons, Ltd.
Although much has been published about curcumin, which is obtained from turmeric, comparatively little is known about turmeric itself. Turmeric, a golden spice obtained from the rhizome of the plant Curcuma longa, has been used to give color and taste to food preparations since ancient times. Traditionally, this spice has been used in Ayurveda and folk medicine for the treatment of such ailments as gynecological problems, gastric problems, hepatic disorders, infectious diseases, and blood disorders. Modern science has provided the scientific basis for the use of turmeric against such disorders. Various chemical constituents have been isolated from this spice, including polyphenols, sesquiterpenes, diterpenes, triterpenoids, sterols, and alkaloids. Curcumin, which constitutes 2-5% of turmeric, is perhaps the most-studied component. Although some of the activities of turmeric can be mimicked by curcumin, other activities are curcumin-independent. Cell-based studies have demonstrated the potential of turmeric as an antimicrobial, insecticidal, larvicidal, antimutagenic, radioprotector, and anticancer agent. Numerous animal studies have shown the potential of this spice against proinflammatory diseases, cancer, neurodegenerative diseases, depression, diabetes, obesity, and atherosclerosis. At the molecular level, this spice has been shown to modulate numerous cell-signaling pathways. In clinical trials, turmeric has shown efficacy against numerous human ailments including lupus nephritis, cancer, diabetes, irritable bowel syndrome, acne, and fibrosis. Thus, a spice originally common in the kitchen is now exhibiting activities in the clinic. In this review, we discuss the chemical constituents of turmeric, its biological activities, its molecular targets, and its potential in the clinic. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Cancer of the gallbladder is rare but fatal, and has an unusual geographic and demographic distribution. Gallstones and obesity have been suggested as possible risk factors. As diet is known to influence both these factors, we carried out the present study to evaluate the possible role of diet in gallbladder carcinogenesis. A case-control study involving 64 newly diagnosed cases of gallbladder cancer and 101 cases of gallstones was carried out. The dietary evaluation was carried out by the dietary recall method based on a preset questionnaire developed specifically for the present study, keeping in mind the common dietary habits prevailing in this part of the world. Odds ratios (OR) and 95% confidence interval (CI) were calculated for various dietary items. A significant reduction in odds ratio was seen with the consumption of radish (OR 0.4; 95% CI 0.17-0.94), green chilli (OR 0.45; 95% CI 0.21-0.94) and sweet potato (OR 0.33; 95% CI 0.13-0.83) among vegetables, and mango (OR 0.4; 95% CI 0.16-0.99), orange (OR; 0.45; 95% CI 0.22-0.93), melon (OR 0.3; 95% CI 0.14-0.64) and papaya (OR 0.44; 95% 0.2-0.64) among fruits. A reduction in odds was also seen with the consumption of cruciferous vegetables, beans, onion and turnip, however the difference was not statistically significant. On the other hand, an increase in the odds was observed with consumption of capsicum (OR 2.2), beef (OR 2.58), tea (OR 1.98), red chilli (OR 1.29) and mutton (OR 1.2), however the difference was statistically not significant. In conclusion, the results of the present study show a protective effect of vegetables and fruits on gallbladder carcinogenesis, but red meat (beef and mutton) was found to be associated with increased risk of gallbladder cancer.
Several epidemiologic studies have shown that chronic inflammation predisposes individuals to various types of cancer. Many cancers arise from sites of infection, chronic irritation, and inflammation. Conversely, an oncogenic change induces an inflammatory microenvironment that promotes the development of tumors. Natural bioactive compounds in dietary plant products including fruits, vegetables, grains, legumes, tea, and wine are claimed to help prevent cancer, degenerative diseases, and chronic and acute inflammation. Modern methods in cell and molecular biology allow us to understand the interactions of different natural bioactive compounds with basic mechanisms of inflammatory response. The molecular pathways of this cancer-related inflammation are now unraveled. Natural bioactive compounds exert anti-inflammatory activity by modulating pro-inflammatory gene expressions have shown promising chemopreventive activity. This review summarizes current knowledge on natural bioactive compounds that act through the signaling pathways and modulate inflammatory gene expressions, thus providing evidence for these substances in cancer chemopreventive action.
Dietary factors such as fruit and vegetables are thought to reduce the risk of cancer incidence and mortality. We investigated the effect of a diet rich in fruit and vegetables against the long-term effects of radiation exposure on the risk of cancer. A cohort of 36,228 atomic-bomb survivors of Hiroshima and Nagasaki, for whom radiation dose estimates were currently available, had their diet assessed in 1980. They were followed for a period of 20 years for cancer mortality. The joint-effect of fruit and vegetables intake and radiation exposure on risk of cancer death was examined, in additive (sum of effects of diet alone and radiation alone) and multiplicative (product of effects of diet alone and radiation alone) models. In the additive model, a daily intake of fruit and vegetables significantly reduced the risk of cancer deaths by 13%, compared to an intake of once or less per week. Radiation exposure of 1 Sievert (Sv) increased significantly the risk of cancer death by 48-49%. The additive joint-effects showed a lower risk of cancer among those exposed to 1 Sv who had a diet rich in vegetables (49%-13%=36%) or fruit (48%-13%=35%). The multiplicative model gave similar results. The cancer risk reduction by vegetables in exposed persons went from 52% (effect of radiation alone) to 32% (product of effect of vegetables and radiation), and cancer risk reduction by fruit was 52% (radiation alone) to 34% (product of effect of fruit and radiation). There was no significant evidence to reject either the additive or the multiplicative model. A daily intake of fruit and vegetables was beneficial to the persons exposed to radiation in reducing their risks of cancer death.
Many studies have supported the protective effects of broccoli and broccoli sprouts against cancer. The chemopreventive properties of sulforaphane, which is derived from the principal glucosinolate of broccoli and broccoli sprouts, have been extensively studied. Recent research into the effects of sulforaphane on cancer stem cells (CSCs) has drawn lots of interest. CSCs are suggested to be responsible for initiating and maintaining cancer, and to contribute to recurrence and drug resistance. A number of studies have indicated that sulforaphane may target CSCs in different types of cancer through modulation of NF-κB, SHH, epithelial-mesenchymal transition and Wnt/β-catenin pathways. Combination therapy with sulforaphane and chemotherapy in preclinical settings has shown promising results. In this article, we focus on the effects of sulforaphane on CSCs and self-renewal pathways, as well as giving a brief review of recent human studies using broccoli sprout preparations.
Research leading to the discovery of a series of mutagenic and carcinogenic heterocyclic amines (HCAs) was inspired by the idea that smoke produced during cooking of food, especially meat or fish, might be carcinogenic. More than ten kinds of HCAs, actually produced by cooking or heating of meat or fish, have now been isolated and their structures determined, most being previously unregistered compounds. They are highly mutagenic towards Salmonella typhimurium in the presence of S9 mix and are also mutagenic in vitro and in vivo toward mammalian cells. HCAs have now been chemically synthesized in quantity and subjected to long-term animal testing. When HCAs were fed in the diet, rodents developed cancers in many organs, including the colon, breast and prostate, and one HCA produced hepatomas in monkeys. The lesions exhibited alteration in genes including Apc, beta-catenin and Ha-ras, and these changes provide clues to the induction mechanisms. The HCAs are oxidized to hydroxyamino derivatives by cytochrome P450s, and further converted to ester forms by acetyltransferase and sulfotransferase. Eventually, they produce DNA adducts through the formation of N-C bonds at guanine bases. There are HCA-sensitive and resistant strains of rodents and a search for the responsible genes is now under way. While the content of HCAs in dishes consumed in ordinary life is low and not sufficient in itself to explain human cancer, the coexistence of many other mutagens/carcinogens of either autobiotic or xenobiotic type and the possibility that HCAs induce genomic instability and heightened sensitivity to tumor promoters suggest that avoidance of exposure to HCAs or reduction of HCAs' biological effects as far as possible are to be highly recommended. Usage of microwave ovens for cooking and supplementation of the diet, for example with soy-isoflavones, which have been found to suppress the occurrence of HCA-induced breast cancers, should be encouraged. Advice to the general public about how to reduce the carcinogenic load imposed by HCAs would be an important contribution to cancer prevention.