Here is a list of eighteen main anti-carcinogenic fruits and vegetables.
Fruits and vegetables are extensively studied and proved to be effective in cancer treatment.
1. Pomegranate (Punica Granatum):
Pomegranate is considered as the “nature’s power fruit.” In the past decade numerous studies on the antioxidant, anti-carcinogenic, and anti-inflammatory properties of pomegranate constituents have been published, focusing on treatment and prevention of cancer, cardiovascular disease, diabetes, dental conditions, erectile dysfunction, bacterial infections, antibiotic resistance, and ultraviolet radiation- induced skin damage.
Other potential applications include infant brain ischemia, male infertility, Alzheimer’s disease, arthritis, and obesity. The synergistic action of the pomegranate constituents appears to be superior to that of single constituents. All forms of pomegranate preparations were found to inhibit PC-3 cell invasion through Matrigel and also inhibited the growth of PC-3 xenograft in athymic nude mice.
Prostate cancer is the second leading cause of cancer-related deaths among U.S. males with a similar trend in many western countries. Recent researches have shown that pomegranate extracts selectively inhibit the growth of breast, prostate, colon and lung cancer cells in culture. Malik and Mukhtar (2006) showed that pomegranate fruit extract through modulations in the cyclin kinase inhibitor-cyclin-dependent kinase machinery, resulted in inhibition of cell growth followed by apoptosis of highly aggressive human prostate carcinoma PC-3 cells.
Components from pomegranate fruit each belonging to different representative chemical classes and showing known anti-cancer activities have been tested as potential inhibitors of In vitro invasion of human prostate cancer cells in an assay employing Matrigel artificial membranes.
In preclinical animal studies, oral consumption of pomegranate extract inhibited growth of lung, skin, colon and prostate tumors. Sartippour et al (2008) concluded from their study that an ellagitannin-rich pomegranate extract can inhibit tumor-associated angiogenesis as one of several potential mechanisms for slowing the growth of prostate cancer in chemo-preventive applications.
Colon cancer is one of the major causes of cancer-related death in the Western world. Pomegranate fruit extracts (PFEs) possess polyphenols and other compounds with anti-proliferative, pro-apoptotic and anti-inflammatory effects in prostate, lung, and other cancers. Further, the inhibition of motility and invasion by the fruit extracts, coincident with suppressed RhoC and RhoA protein expression, suggests a role for these defined extracts in lowering the metastatic potential of aggressive breast cancer species.
Khan et al (2007; 2009) found the fruit extract to be a useful chemo-preventive/chemo- therapeutic agent against human lung cancer too. Further, polyphenols constituents in the pomegranate have been found to play an important role in the modulation of inflammatory signals in colon cancer cells also.
Fermented pomegranate juice resulted in 42 per cent reduction in the number of lesions compared with control, whereas the peak separated from the fermented juice and the pomegranate seed oil each resulted in 87 per cent reduction in number of tumorigenic lesions. The results suggested enhanced potential for the purified compound as well as pomegranate seed oil both greater than pomegranate fermented juice polyphenols.
The inhibition and apoptosis induction were significantly higher in the combination treatments consisting of pomegranate extracts and genistein than in the single treatments with either agent although both pomegranate extract and genistein independently had significant – and time-dependent cytotoxic effects on MCF-7 cells.
Pomegranate seed oil has been investigated for possible skin cancer chemo- preventive efficacy in mice. A multi-centric study was conducted by Albrecht et al. (2004) of the effects of pomegranate cold-pressed (Oil) or supercritical CO2-extracted (S) seed oil, fermented juice polyphenols (W), and pericarp polyphenols (P) on human prostate cancer cell xenograft growth in vivo, and/or proliferation, cell cycle distribution, apoptosis, gene expression, and invasion across Matrigel, in vitro. Oil, W, and P each acutely inhibited in vitro proliferation of LNCaP, PC-3, and DU-145 human cancer cell lines showing the anti-tumor activity of pomegranate derived materials against human prostate cancer mediated by changes in both cell cycle distribution and induction of apoptosis.
2. Papaya (Carica Papaya L.):
Various parts of Carica papaya (CP) have been traditionally used as ethno-medicine for a number of disorders, including cancer. There have been anecdotes of patients with advanced cancers achieving remission following consumption of tea extract made from CP leaves. The active components of CP extract, which inhibits tumor cell growth and stimulates anti-tumor effects, is the fraction with molecular weight less than 1000.
3. Grape Seeds (Vitis Vinifera):
Grape seed extract is a rich source of pro anthocyanidins. It acts against colorectal cancer and also protects the liver from oxidative damage following bile duct ligation in rats. This effect possibly involves the inhibition of neutrophil infiltration and lipid peroxidation, and thus restoration of oxidant and anti-oxidant balance in the tissue. The growth inhibitory and apoptotic effects of Grape seed extract against colorectal cancer could be mediated via an up-regulation of Cip1 /p21.
Pakhale et al. (2007) and Ramchandani et al. (2008) found both seedless and seeded grape seed extracts to possess anti-tumor activity in target tissues of mice as was evident from their ability to delay tumor formation along with a significant decrease in tumor multiplicity and incidence.
Sharma et al. (2004) showed a strong possibility of synergistic efficacy of grape seed extract and doxorubicin combination for breast cancer treatment, independent of estrogen receptor status of the cancer cell. Leifert and Abeywardena (2008) observed inhibition of cholesterol uptake and pro-inflammatory 5-LOX activity to be beneficial in preventing the development of chronic degenerative diseases such as cardiovascular disease and cancer.
Singh et al (2004) found that feeding grape seed extract strongly inhibited tumor growth that accounted for 59-73 per cent (p < 0.001) inhibition in tumor volume and 37-47 per cent (p < 0.05) decrease in tumor weight at the end of the experiment without affecting the body weight gain profile and diet consumption. Immuno-histochemical analysis of tumors showed that grape seed extract decreases proliferation index by 51-66 per cent (p < 0.001) and increases apoptotic index by 3-4 fold (p < 0.001).
CD31 staining for endothelial cells, showed decrease in intra-humoral micro-vasculature in grape seed extract-fed group of mice. Thus, the authors suggested that grape seed possesses anticancer efficacy against hormone-refractory human PCA, which is associated with its anti-proliferative, pro-apoptotic and anti-angiogenic activities together with up-regulation of IGFBP-3. Hence it is beneficial in the treatment of chronic degenerative diseases such as cardiovascular disease and cancer.
Studies from various scientific groups conclude that both grapes and grape- based products are excellent sources of various anticancer agents and their regular consumption should thus be beneficial to the general population. Grape waste management is one of the main problems of winery industries, but, conversely, grape waste contains a high amount of polyphenols that might protect against human diseases related to oxidative stress, such as colorectal cancer.
Lazze et al (2009) by the clonogenic assay and the cell cycle distribution analysis observed that the grape extract has a significant anti-proliferative effect in a tumor cell line indicating that grape extract is a promising product to be used as an anti-free radical agent and could exert a chemo-preventive action. Anter et al (2011) suggested that red table grapes are potent anti-mutagens that protect DNA from oxidative damage as well as being cytotoxic toward the HL60 tumor cell line.
Interestingly, recent patents regarding grape polyphenols show a tendency to depend on a minimum use of severe extraction processes and organic solvents.
4. Litchi Fruit (Litchi Chinensis):
Litchi fruit pericarp (LFP) extract exhibited potential anti-cancer activity against hepato-cellular carcinoma in vitro and in vivo through inhibition of proliferation and apoptosis induction of cancer cells Wang et al. (2006b) demonstrated that litchi fruit extract might have potential anti-cancer activity on both ER positive and negative breast cancers, which could be attributed, in part, to its DNA damage effect, proliferating inhibition and apoptosis induction of cancer cells through up-regulation and down-regulation of multiple genes involved in cell cycle regulation and cell proliferation, apoptosis, signal transduction and transcriptional regulation, motility and invasiveness of cancer cells.
ADP-ribosyl transferase (NAD+; poly (ADP-ribose) polymerase)-like 1 (ADPRTL1), Cytochrome P450, subfamily I and Hyaluronan-mediated motility receptor might be the main molecular targets at which LFP water-soluble crude ethanolic extract acted.
The anti-breast cancer activities of epicatechin, proanthocyanidin B2, pro-anthocyanidin B4 and the ethyl acetate fraction was much higher on splenocyte proliferation than that of the reference rutin. Epicatechin and pro-anthocyanidin B2 had lower cyto-toxicities to human breast cancer cell MCF-7 and human embryolic lung fibroblast than paclitaxel.
Recent studies have revealed that Litchi pericarp is composed of significant amounts of flavonoids and anthocyanins, including procyanidin B2, B4, epicatechin, cyanidin-3-rutinoside, cyanidin-3-glucoside, quercetin-3-retinoside, quercetin-3- glucoside etc. These components carry high free radical scavenging properties and could be used as anti-inflammation, anti-oxidation, or anti-cancer agents. Therefore it is suggested that flavonoids from litchi fruit pericarp might be potentially useful components for functional foods and/or anti-breast cancer.
In addition to the anti-oxidant activity, litchi fruit pericarp extract displayed a dose- and time-dependent inhibitory effect on human breast cancer, which was attributed, in part, to inhibition of proliferation and induction of apoptosis in cancer cells through up-regulation and down-regulation of multiple genes. Furthermore, various anti-cancer activities were observed for epicatechin, procyanidin B2, procyanidin B4 and the ethyl acetate fraction of LFP tissue extracts.
Procyanidin B4 and the ethyl acetate fraction showed a stronger inhibitory effect on HELF than MCF-7 proliferation, while epicatechin and procyanidin B2 have lower cyto-toxicities towards MCF-7 and HELF than paclitaxel. Therefore the authors suggested that flavonoids from LFP might be potentially useful components for functional foods and/or anti-breast cancer.
Pharmacological studies have revealed that Litchi seeds exert anti-hyper-lipidemic, hypoglycemic, and anti-tumor effects. In India, the seeds are powdered as an herbal medicine owing to their astringency, and after oral intake they have the reputation of relieving neuralgic pains. Hsu et al. (2012) provided in vitro evidence that polyphenol- rich litchi seed ethanol extract serves as a potential chemo-preventive agent for colorectal cancer.
5. Berries:
The anticancer potential of berries has been related, at least in part, to a multitude of bioactive phytochemicals that these colorful fruits contain, including polyphenols (flavonoids, proanthocyanidins, ellagitannins, gallotannins, phenolic acids), stilbenoids, lignans, and triterpenoids. This diverse range of phytochemicals with biological properties such as antioxidant, anticancer, anti-neurodegerative, and anti-inflammatory activities.
Six popularly consumed berries- blackberry, black raspberry, blueberry, cranberry, red raspberry and strawberry showed with increasing concentration of berry extract, increasing inhibition of cell proliferation in all of the cell lines.
Duthie (2007) in his review found a strong and convincing evidence that berry extracts and berry phytochemicals modulate biomarkers of DNA damage and indicators of malignant transformation in vitro and in vivo. Data from numerous cell culture and animal models indicate that berry components such-as the anthocyanins are potent anti-carcinogenic agents and are protective against genomic instability at several sites in the carcinogenic pathway.
Anti-carcinogenic mechanisms include modulation of carcinogen activation and detoxification, decreased DNA binding of the carcinogen, inhibition of oxidative DNA damage, alteration in cell signalling and malignant transformation and inhibition of cell invasiveness and metastasis. But still feels that the evidence in human studies is weak.
6. Cran Berry (Vaccinium Microcarpon):
The main phenolic compounds in European, small-fruited cranberries were pro- anthocyanidins comprising 63-71 per cent of the total phenolic content, but anthocyanins, hydroxycinnamic acids, hydroxybenzoic acids, and flavonols were also found. Pro-anthocyanidins are polymeric phenolic compounds consisting mainly of catechin, epicatechin, gallocatechin, and epigallocatechin units.
Cranberry phenolic extract inhibited LPS-induced NO production in a dose-dependent manner, but it had no major effect on iNOS of COX-2 expression. At a concentration of 100 µg/ml cranberry phenolic extract inhibited LPS-induced IL-6, IL-1β and TNF- α production. Thus, the phenolics, notably pro-anthocyanidins (oligomers and polymers), in cranberries exert multiple bioactivities that may be exploited in food development.
The enhanced anti-proliferative activity of total polyphenols compared to total cranberry extract and its individual phytochemicals suggests synergistic or additive anti-proliferative interactions of the anthocyanins, pro-anthocyanidins, and flavonol glycosides within the cranberry extract.
In vitro studies using a variety of tumor models show that polyphenolic extracts from V. macrocarpon inhibit the growth and proliferation of breast, colon, prostate, lung, and other tumors, as do flavonols, pro-anthocyanidin oligomers and triterpenoids isolated from the fruit. The phytochemicals prevent cardiovascular diseases, various cancers, and infections involving the urinary tract, dental health, and Helicobacter pylori-induced stomach ulcers and cancers.
Possible chemo-preventive mechanisms of action by cranberry phytochemicals include induction of apoptosis in tumor cells, reduced ornithine decarboxylase activity, decreased expression of matrix metallo-proteinases associated with prostate tumor metastasis, and anti-inflammatory activities including inhibition of cyclo-oxygenases. These findings suggest a potential role for cranberry as a dietary chemo preventive and provide direction for future research.
7. Deer Berry (Vaccinium Stamineum):
Wang et al. (2007) found Deer berries to contain potent free radical scavenging activities. Pre-treatment of JB6 P (+) mouse epidermal cells with deer berry fruit extracts produced an inhibition on the activation of activator protein-1 (AP-1) and nuclear factor-kappaB (NF-kappaB) induced by either 12- O-tetra-decanoylphorbol 13-acetate (TPA) or ultraviolet-B (UVB).
Deer berry fruit extracts also blocked TPA- or UVB- induced phosphorylation of ERKs and MEK 1/2, two upstream regulators of AP-1 and inhibited proliferation of human leukemia HL-60 cancer cells and human lung epithelial cancer A549 cells and induced apoptosis of HL-60 cells.
8. Lingon Berry (Vaccinium Vitis-Idaea):
The extract of Lingon berry (also known as red cowberries) suppressed TPA-induced neoplastic transformation of JB6 P(+) cells in a dose-dependent manner. Lingon berry extract also induced the apoptosis of human leukemia HL-60 cells in a dose- independent manner.
9. Black Raspberry (Rubus Occidentalis):
The ability of black raspberries to inhibit tumor development maybe mediated by impairing signal transduction pathways leading to activation of AP-1 and NF- kappaB. The RU-ME fraction appears to be the major fraction responsible for the inhibitory activity of black raspberries. In view of the important roles of AP-1 and VEGF in tumor development, one mechanism for the chemo- preventive activity of black raspberries may be inhibition of the PI-3K/Akt/AP-1/VEGF pathway.
Lu et al. (2006) showed that pretreatment of mouse epidermal CI 41 cells with methanol-extracted blackberry fraction RO-ME resulted in a dramatic inhibition of B(a)PDE-induced activation of AP-1 and NF-kappaB, and expression of VEGF and COX-2. The RO-ME fraction appears to be the major fraction responsible for the inhibitory activity of black raspberries.
Further, Huang et al. (2007; 2008a) observed that the inhibition of UV-induced signaling pathways is specific for black raspberries and NF- kappaB. Cyanidin-3- rutinoside, an anthocyanin found in abundance in black raspberries. Black raspberry fractions inhibited the activation of AP-1, NF-kappaB, and nuclear factor of activated T cells (NFAT) by BaPDE as well as their upstream PI-3K/Akt-p70 (S6K) and mitogen- activated protein kinase pathways.
In contrast, strawberry fractions inhibited NFAT activation, but did not inhibit the activation of AP-1, NF-kappaB or the PI-3K/Akt- p70 (S6K) and mitogen-activated protein kinase pathways. Consistent with the effects on NFAT activation, tumor necrosis factor-alpha (TNF-alpha) induction by BaPDE was blocked by extract fractions of both black raspberries and strawberries, whereas vascular endothelial growth factor (VEGF) expression, which depends on AP-1 activation, was suppressed only by black raspberry fractions but not strawberry fractions. Li et al. (2008) thus demonstrated that black raspberry and strawberry components may target different signaling pathways in exerting their anti- carcinogenic effects.
10. Black Current (Ribes Nigrum):
Black currant (Raisins) is known to contain high amounts of anthocyanins (250 mg/100 g fresh fruit). Black currant fruits have been used in Asian and European traditional medicine for the treatment of a variety of diseases. Black currant extract has recently been found to be the second most effective amongst nine different berry extracts studied for their free radical scavenging activity.
Constituents present in black currant juice have been found to exert a number of health-promoting effects, including immuno-modulatory, antimicrobial and anti-inflammatory actions, inhibition of low- density lipoprotein, and reduction of cardiovascular diseases. Bishayee et al. (2010) demonstrated that black currant skin containing an anthocyanin-rich fraction inhibits the proliferation of liver cancer cells, possibly due to additive as well as synergistic effects.
Again, Edirisinghe et al. (2011) demonstrated that black current concentrates (Ben Gairn and Ben Hope – commercial products) also could activate eNOS via Akt/ PI3 kinase pathway in vitro in human umbilical vein endothelial cells and that the effect was not dependent on vitamin C.
11. Amla (Emblica Officinalis Gaertn or Phyllanthus Emblica):
Amla, is arguably the most important medicinal plant in the Indian traditional system of medicine, the Ayurveda. Different parts of the plants show anti-diabetic, hypo-lipidemic, anti-bacterial, anti-oxidant, anti-ulcerogenic, hepato-protective, gastro-protective, and chemo-preventive properties. Baliga and Dsouza (2011) summarized the results of the review and reported that amla and some of its phytochemicals such as gallic acid, ellagic acid, pyrogallol, some nor-sesquiterpenoids, corilagin, geranial, elaeocarpusin, and pro-delphinidins B1 and B2 also possess anti-neoplastic effects.
Amla is also reported to possess radio- modulatory, chemo-modulatory, chemo-preventive effects, free radical scavenging, anti-oxidant, anti-inflammatory, anti-mutagenic and immuno-modulatory activities, properties that are efficacious in the treatment and prevention of cancer.
Experimental studies in the past decade have shown that Triphala composed of the three medicinal fruits Phyllanthus emblica L. or Emblica officinalis Gaertn., Terminalia chebula Retz., and Terminalia belerica Retz. is useful in the prevention of cancer and that it also possesses anti-neoplastic, radio-protective and chemo-protective effects.
12. Broccoli (Brassica Oleracea):
Bioactive chemicals in broccoli include glucosinolates, plant pigments including kaempferol, quercetin, lutein and carotenoids, various vitamins, minerals and amino acids. Cancer prevention is hypothesised to act through various mechanisms including modulation of xenobiotic metabolising enzymes, NF-E2 p45-related factor- 2 (Nrf2)-mediated stress-response mechanisms, and protection against genomic instability.
Broccoli and broccoli extracts also regulate the progression of cancer through anti-inflammatory effects, effects on signal transduction, epigenetic effects and modulation of the colonic micro flora. Broccoli contains isothiocyanates that induce carcinogen-detoxifying enzymes. Glutathione transferase enzymes conjugate isothiocyanates, leading to excretion. Keck and Finley (2006) demonstrated that Se and sulforaphane, alone or as a component of broccoli, may help decrease oxidative stress.
They further suggest that Se is the most important element to decrease oxidative stress, but maximizing the Se content of broccoli also may compromise its ability to induce Phase II detoxification proteins. According to Tsai et al. (2013) regardless of Se content, the cytotoxicity in HCT116 cells of both high-Se (H-SeB) or low-Se (L-SeB) enzymatic-digested Se-enriched broccoli extracts (SeB) forms appeared to be H2O2-independent, whereas the cytotoxicity in HCT116+Chr.3 of either SeB form appeared to be H202-dependent with an increase in anti-oxidative ability for H-SeB.
Broccoli on Lung Cancer:
The risk for lung cancer among those in the highest category of total cruciferous vegetable intake was 22 per cent lower in case-control studies and 17 per cent lower in cohort studies compared with those in the lowest category of intake. Broccoli is a rich source of glucosinolates. The anti- carcinogenic properties of cruciferous vegetables may be attributable to isothiocyanates derived specifically from glucosinolates.
Several experimental and mechanistic studies support a potential anti-cancer role of isothiocyanates. Sulforaphane, an isothiocyanate found in broccoli, is involved in several pathways including induction of detoxifying genes, cell cycle control, and apoptosis; acting as an anti-oxidant and inhibiting histone deacetylase.
Broccoli on Prostate Cancer:
Epidemiological studies suggest that people who consume more than one portion of cruciferous vegetables per week are at lower risk of both the incidence of prostate cancer and of developing aggressive prostate cancer. Srivastava et al. (2003) demonstrated that administration of allyl isothiocyanate inhibits growth of PC-3 xenografts in vivo by inducing apoptosis and reducing mitotic activity.
Joseph et al. (2004) provided evidence that two or more servings per month of cruciferous vegetables may reduce risk of prostate cancer, especially among men with glutathione S- transferase M1-present alleles and are consistent with a role of dietary Isothiocyanates as chemo-preventive agents against prostate cancer. Further, a high intake of broccoli has been found to reduce the risk of aggressive prostate cancer.
A protective effect of broccoli was observed when broccoli in combination with the glutathione transferase M1 (GSTM1) null genotype was consumed and to be associated with a lower prevalence of colorectal adenomas because of higher isothiocyanate levels.
Traka etal. (2008) observed that broccoli interacts with GSTM1 genotype to result in complex changes to signalling pathways associated with inflammation and carcinogenesis in the prostate. The authors proposed that these changes may be mediated through the chemical interaction of isothiocyanates with signalling peptides in the plasma. This is the first experimental evidence in humans to support that diets rich in cruciferous vegetables may reduce the risk of prostate cancer and other chronic disease.
13. Bitter Gourd (Momordica Charantia):
Several studies have demonstrated that leaf or fruit extracts of Momordica charantia (MC) exert antineoplastic effects against various cancers. Phytochemicals in MC that have been documented with cytotoxicity on cancer cells include proteins, triterpenoids, and their glycosides. Ribosome-inactivated proteins and a chemical analogue, MAP30, in MC have been reported to exhibit the cytotoxicity and inhibit the metastasis of the highly metastatic human breast cancer MDA-MB-231 cells and considered to be potential therapeutic agents against breast carcinomas.
Fruits of the Thai bitter gourd, strongly enhanced glutathione S-transferase activity and the fruit contain mono-functional phase II enzyme inducers and compounds capable of repressing some mono-oxygenases, especially those involved in the metabolic activation of chemical carcinogens. Thai bitter gourd fruits but not Chinese bitter gourd may possess chemo-preventive potential. Extracts of MC have been shown to inhibit proliferation of human breast cancer cells by inducing cell cycle arrest and apoptosis.
Several groups of investigators have reported that treatment of bitter-melon- related products in a number of cancer cell lines induces cell cycle arrest and apoptosis without affecting normal cell growth. Li et al. (2012) demonstrated the apoptosis induced by methanol extract of MC (MCME) on human lung adeno-carcinoma CL1-0 cells through caspase and mitochondria-dependent pathways, which changes of the anti-proapoptotic Bcl-2 and proapoptotic Bax proteins were included.
Methanol extract of Momordica charantia (MCME) was evaluated for its cytotoxic activity on four human cancer cell lines, Hone-1 nasopharyngeal carcinoma cells, AGS gastric adeno-carcinoma cells, HCT-116 colorectal carcinoma cells, and CL1-0 lung adeno-carcinoma cells. The findings according to Li et al. (2012) pointed to its cytotoxic effects on human cancer cells and exhibited promising anti-cancer activity by triggering apoptosis through the regulation of caspases and mitochondria. Bitter gourd is a very popular vegetable in many Asian countries. MAP30 (a natural component from M. charantia, as an anticancer agent against liver cancer) would serve as a novel and relatively safe agent for prophylaxis and treatment of liver cancer.
14. Drumstick (Moringa Oleifera):
The high anti-oxidant/radical scavenging effects observed for different parts of M.oleifera appear to provide justification for their widespread therapeutic use in traditional medicine in different continents. The possibility that this high anti- oxidant/radical scavenging capacity may impact on the cancer chemo-preventive potential of the plant. The anti-neoplastic effects of M. oleifera have been evaluated in animal models.
Relevant human trials showed that this plant may offer anti-tumor benefits, and could also enhance the sensitivity of tumor cells to ordinary chemotherapy. M. oleifera possesses anti-tumor, anti-pyretic, anti-epileptic, anti-inflammatory, anti-ulcer, anti-spasmodic, diuretic, anti-hypertensive, cholesterol- lowering, anti-oxidant, anti-diabetic, and renal- and hepato-protective activities.
The hydro-ethanolic extract of M. oleifera reduced the formation of free radicals, enhanced the levels of anti-oxidants in 7,12- dimethylbenz [a] anthracene induced carcinogenesis rationalizing the ethno- medicinal use of drumstick for the protection against nephrotoxicity induced by chemical carcinogens.
15. Tulasi (Ocimum Sanctum):
Ocimum sanctum has been known to possess various beneficial properties including anti-cancer activities. Tulsi arrests cancer if detected at first stage. In laboratory animals, it has been shown to prevent cancer and to protect against radiation. A study from Madras established that hamsters were protected from developing cancer of the mouth by taking holy basil. The seed oil was evaluated for chemo-preventive activity against subcutaneously injected 20-methylcholanthrene induced-fibrosarcoma tumors in the thigh region of Swiss albino mice.
Enhanced survival rate and delay in tumor incidence was observed in seed oil supplemented mice. Liver enzymatic (superoxide dismutase, catalase, glutathione-S-transferase), non-enzymatic antioxidants (reduced glutathione) and lipid peroxidation end product, malondialdehyde levels were significantly modulated with oil treatment as compared to untreated 20-methylcholanthrene injected mice. The potential chemo preventive activity of the oil is partly attributable to its antioxidant properties.
The chemo – preventive efficacy of seed oil (100-ml/kg) was comparable to that of 80 mg/ kg of vitamin E. Kim et al. (2010) support that Ethanolic extract of Ocimum sanctum can be a potent anti-metastatic candidate through inactivation of MMP-9 and enhancement of anti-oxidant enzymes.
Male Wistar rats that were treated with extracts showed low levels of TBARS, ALT, and AST, which clearly indicates the extract had no toxic effects on hepatocytes. Again, there was no significant difference between Ocimum gratissimum and Ocimum canum from Southern Africa except in the levels of vitamins E and C. Thus, George and Chaturvedi (2009) reported that there is a possibility that O. canum might be participating through vitamin C and O. gratissimum through vitamin E.
At the concentration of 50 µg/kg in the in vitro system the flavonoids, orientin and vicenin showed a significantly greater free radical-inhibiting activity. Neither orientin nor vicenin showed any pro-oxidant activity at the concentrations tested. Both compounds inhibited free radical formation in the absence of EDTA. Free radical scavenging appears to be the possible mechanism of radiation protection by these flavonoids. Thus the results indicated a significant protection by these extracts against ethanol-induced hepato-toxicity (p < or = 0.05).
16. Betel Leaves (Piper Betel):
The mutagenic activity of betel quid and its ingredients using four strains of S. typhimurium tester strains was determined. Aqueous extract of betel leaf was not mutagenic in any of the four strains. At the same time, when betel nut extract was fed with betel leaf extract, the lung tumorogenisity induced by the nut reduced from 47 per cent to 38 per cent indicating the protective role of betel leaf. Betel leaf water and acetone extracts reduce the mutagenicity of benzo(a)pyrene and dimethylbenzanthracene. Acetone extract is more potent than water extract in inhibiting mutagenicity of environmental mutagens.
Based on the studies on stomach tumor models and mice, betel leaf extract has been proved to be a promising anti-carcinogenic agent in tobacco-induced cancers and also against environmental mutagens. Similarly, it was also observed that the phenolic compound, ‘hydroxychavicol (HC)’ present in betel leaf suppressed the mutagenic effects of NNK and NNN (N’-nitrosonornicotine) in the test systems of Ames Salmonella/microsome assay and micronucleus test using Swiss male mice thus indicating the role of HC in reducing the risk of oral cancer in betel quid with tobacco chewers.
Chemo-preventive efficacy of betel leaf extracts and its constituents on 7, 12- dimethybenz (a) anthrocene induced carcinogenesis and their effect on drug detoxification system in mouse skin showed that there was a significant inhibition in tumor formation of about 85 per cent by betel leaf extract. The inhibitory effect of oral administration of betel leaf extract or its constituents – beta- carotene and alpha-tocopherol combined with turmeric was higher than that of individual constituents.
Epidemiological studies have implicated chewing tobacco alone to be more hazardous than chewing tobacco with betel quid. Experimental studies have shown that betel leaf is anti-mutagenic against standard mutagens like benzo[a]pyrene and dimethylbenz[a]anthrocene. The tobacco-specific N-nitrosamines (TSNA) are the only carcinogens present in unburnt forms of tobacco, including chewing tobacco. Padma et al. (1989 a; b) observed that betel leaf extract suppressed the mutagenic effects of both the nitrosamines to a significant extent.
Purnark, a mixture of extracts of turmeric, betel leaf and catechu, when tested for its chemo-preventive activity against benzo(a)pyrene-induced DNA damage, seemed to give 50-60 per cent protection against BP induced sister chromatid exchange and micronuclei. Betel leaf extract reduced the tumorigenic effects of NNK (nitrosamine 4- (N-nitrosomethylamino)-1-(3-pyridyl)-1-butanone) by 25 per cent and also inhibited the reduction in vitamin A concentration in liver and plasma induced by NNK. Betel leaf thus has protective effect against the mutagenic, carcinogenic and adverse metabolic effects of NNK in mice.
It appears that the carcinogenic potential of betel is enhanced by the elevated hormonal profile in pregnant women. There is a need to determine if there is an increased likelihood of developing cancer in betel chewing pregnant women due to increased sensitivity of their lymphocytes to genetic damage compared with non- chewing pregnant women.
17. Bael (Aegle Marmelos):
Bael has been used since antiquity for treating various ailments, some of which are now known to be the result of oxidative stress. In studies spanning nearly a decade, it has been observed that bael prevented radiation-induced ill-effects, and the results of these studies indicate that it has the potential to be an effective, nontoxic radio-protective agent.
18. Resveratrol:
Resveratrol, a polyphenol is found in grape skins, peanuts, berries and red wine. It has been shown to possess potent growth inhibitory effects against various human cancer cells. Resveratrol has a number of biological effects in a variety of cell culture systems. Resveratrol produces variable anti-tumor effects in different tumor cell lines infact it inhibits all the three major steps of carcinogenesis- initiation, promotion, and progression.
Resveratrol has also been shown to have growth- inhibitory activity, and induces apoptotic cell death in a number of human cancer cell lines as well as in animal models of carcinogenesis. In U251 glioma cells, treatment with resveratrol led to growth inhibition, induction of apoptosis and G0/G1-phase cell cycle arrest. Further, resveratrol inhibited the growth of human skin squamous cell carcinoma A431 xenograft in nude mice. And its mechanism may be associated with the apoptosis of tumor cell through the depression of Survivin (an inhibitor of apoptosis protein), and the activation of caspase-3.
Resveratrol dose-dependently reduced the incidence, total number and multiplicity of visible hepatocyte nodules. Mean nodular volume and nodular volume as percentage of liver volume was also inhibited upon resveratrol treatment. Histo-pathological examination of liver tissue confirmed the protective effect of resveratrol.
Immuno-histochemical detection of cell proliferation and assay of apoptosis indicated a decrease in cell proliferation and increase of apoptotic cells in the livers of resveratrol- supplemented rats. Resveratrol also induced the expression of pro-apoptotic protein Bax, reduced anti-apoptotic Bcl-2 expression and with a concurrent increase in Bax/ Bcl-2 ratio with respect to DENA control thus providing evidence that resveratrol exerts a significant chemo-preventive effect on DENA-initiated hepato-carcinogenesis through inhibition of cell proliferation and induction of apoptosis.
Yin et al. (2013) showed that resveratrol effectively inhibited the growth of lung cancer in a dose-dependent manner in nude mice. Dias et al. (2013) offered strong preclinical evidence for the utilization of dietary stilbenes, particularly 3M-Res, as novel, potent, effective chemo-preventive agents in prostate cancer.
In the case of cervical cancer resveratrol treatment induced apoptosis in all cell lines, particularly in CaSki cells, as measured by Annexin-V flow cytometry analysis. There was a decrease in the mitochondrial membrane potential (apoptosis) in HeLa, CaSki, and SiHa cells and an increased lysosomal permeability (autophagy) in C33A, CaLo (HPV18 positive), and HeLa cell lines. It is a promising phytomedicine for cancer therapy and further efforts are needed to explore this potential therapeutic strategy.
Anaplastic thyroid carcinoma (ATC) is an extremely aggressive malignancy with undifferentiated features, for which conventional treatments, including radioactive iodine ablation, are usually not effective. Resveratrol inhibited cell growth and enhanced re-differentiation in ATC cells dependent upon the activation of Notch1 signaling. Thus, activation of Notch1 signaling could be a potential therapeutic strategy for ATC patients, and thus warrants further clinical investigation.
Other Foods:
Hui et al. (2010) investigated the anticancer effects of an anthocyanin-rich extract from black rice on breast cancer cells in vitro and in vivo. Oral administration of the extract (100 mg/kg/day) to nude mice bearing MDA-MB-453 cell xenografts significantly suppressed tumor growth and angiogenesis by suppressing the expression of angiogenesis factors MMP-9, MMP-2, and uPA in tumor tissue.