Using Breast Cancer Risk Associated Polymorphisms to Identify Women for Breast Cancer Chemoprevention.

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Elad Ziv

Full Text Available Breast cancer can be prevented with selective estrogen receptor modifiers (SERMs and aromatase inhibitors (AIs. The US Preventive Services Task Force recommends that women with a 5-year breast cancer risk ≥3% consider chemoprevention for breast cancer. More than 70 single nucleotide polymorphisms (SNPs have been associated with breast cancer. We sought to determine how to best integrate risk information from SNPs with other risk factors to risk stratify women for chemoprevention.We used the risk distribution among women ages 35-69 estimated by the Breast Cancer Surveillance Consortium (BCSC risk model. We modeled the effect of adding 70 SNPs to the BCSC model and examined how this would affect how many women are reclassified above and below the threshold for chemoprevention.We found that most of the benefit of SNP testing a population is achieved by testing a modest fraction of the population. For example, if women with a 5-year BCSC risk of >2.0% are tested (~21% of all women, ~75% of the benefit of testing all women (shifting women above or below 3% 5-year risk would be derived. If women with a 5-year risk of >1.5% are tested (~36% of all women, ~90% of the benefit of testing all women would be derived.SNP testing is effective for reclassification of women for chemoprevention, but is unlikely to reclassify women with <1.5% 5-year risk. These results can be used to implement an efficient two-step testing approach to identify high risk women who may benefit from chemoprevention.

COX-independent mechanisms of cancer chemoprevention by anti-inflammatory drugs

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Evrim eGurpinar

2013-07-01

Full Text Available Epidemiological and clinical studies suggest that non-steroidal anti-inflammatory drugs (NSAIDs, including cyclooxygenase (COX-2 selective inhibitors, reduce the risk of developing cancer. Experimental studies in human cancer cell lines and rodent models of carcinogenesis support these observations by providing strong evidence for the antineoplastic properties of NSAIDs. The involvement of COX-2 in tumorigenesis and its overexpression in various cancer tissues suggest that inhibition of COX-2 is responsible for the chemopreventive efficacy of these agents. However, the precise mechanisms by which NSAIDs exert their antiproliferative effects are still a matter of debate. Numerous other studies have shown that NSAIDs can act through COX-independent mechanisms. This review provides a detailed description of the major COX-independent molecular targets of NSAIDs and discusses how these targets may be involved in their anticancer effects. Toxicities resulting from COX inhibition and the suppression of prostaglandin synthesis preclude the long-term use of NSAIDs for cancer chemoprevention. Furthermore, chemopreventive efficacy is incomplete and treatment often leads to the development of resistance. Identification of alternative NSAID targets and elucidation of the biochemical processes by which they inhibit tumor growth could lead to the development of safer and more efficacious drugs for cancer chemoprevention.

Aspirin Metabolomics in Colorectal Cancer Chemoprevention | Division of Cancer Prevention

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Substantial evidence supports the effectiveness of aspirin for cancer chemoprevention in addition to its well-established role in cardiovascular protection. In recent meta-analyses of randomized controlled trials in humans, daily aspirin use reduced incidence, metastasis and mortality from several common types of cancer, especially colorectal cancer. The mechanism(s) by which

Use of nonsteroidal antiinflamatory drugs for chemoprevention of colon cancer

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Milić Aleksandra

2013-01-01

Full Text Available Colorectal cancer is in the third most frequent cancer among malignant tumors of both sexes in developed countries. It is predominantly a disease of older persons and occurs mostly after the age of 60. Although the etiology of colon cancer is unknown, it is assumed to arise as a result of unclear and complex interactions between genetic and environmental factors. The main element in the etiology of colorectal cancer is the process of genetic changes in epithelial cells of colon mucosa. It is believed that specific epidemiological factors such as stress, hypoxia, reduced intake of glucose and other nutrients, a hereditary predisposition to mutagenic effects, the meat in the diet, bile acids, reduced intake of minerals and vitamins as well as changes in pH of feces lead to initiation of the process of carcinogenesis in mucosa of the colon. Cancer chemoprevention is defined as the use of chemical agents in order to block, prevent or delay the reversal development or progress of cancer. It is believed that chemoprevention is a key component of cancer control, and numerous studies indicate potential role of NSAIDs in chemoprevention of colon cancer.

Australian clinicians and chemoprevention for women at high familial risk for breast cancer

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Keogh Louise A

2009-05-01

Full Text Available Abstract Objectives Effective chemoprevention strategies exist for women at high risk for breast cancer, yet uptake is low. Physician recommendation is an important determinant of uptake, but little is known about clinicians' attitudes to chemoprevention. Methods Focus groups were conducted with clinicians at five Family Cancer Centers in three Australian states. Discussions were recorded, transcribed and analyzed thematically. Results Twenty three clinicians, including genetic counselors, clinical geneticists, medical oncologists, breast surgeons and gynaecologic oncologists, participated in six focus groups in 2007. The identified barriers to the discussion of the use of tamoxifen and raloxifene for chemoprevention pertained to issues of evidence (evidence for efficacy not strong enough, side-effects outweigh benefits, oophorectomy superior for mutation carriers, practice (drugs not approved for chemoprevention by regulatory authorities and not government subsidized, chemoprevention not endorsed in national guidelines and not many women ask about it, and perception (clinicians not knowledgeable about chemoprevention and women thought to be opposed to hormonal treatments. Conclusion The study demonstrated limited enthusiasm for discussing breast cancer chemoprevention as a management option for women at high familial risk. Several options for increasing the likelihood of clinicians discussing chemoprevention were identified; maintaining up to date national guidelines on management of these women and education of clinicians about the drugs themselves, the legality of "off-label" prescribing, and the actual costs of chemopreventive medications.

Sulforaphane (SFN: An Isothiocyanate in a Cancer Chemoprevention Paradigm

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Mohammad Fahad Ullah

2015-07-01

Full Text Available The International Agency for Research on Cancer (IARC in its latest World Cancer Report (2014 has projected the increase in the global cancer burden from 14 million (2012 to 22 million incidence annually within the next two decades. Such statistics warrant a collaborative engagement of conventional and complementary and alternative therapies to contain and manage cancer. In recent years, there has been a shift in the cancer chemoprevention paradigm with a significant focus turning towards bioactive components of human diets for their anticancer properties. Since diet is an integral part of lifestyle and given that an estimated one third of human cancers are believed to be preventable though appropriate lifestyle modification including dietary habits, the current shift in the conventional paradigm assumes significance. Several epidemiological studies have indicated that consumption of broccoli is associated with a lower risk of cancer incidence including breast, prostate, lung, stomach and colon cancer. The edible plant belonging to the family of cruciferae such as broccoli is a rich source of glucoraphanin, a precursor of isothiocyanate sulforaphane which is considered to be a potent anti-cancer agent. Plant-based dietary agents such as sulforaphane mimic chemotherapeutic drugs such as vorinostat, possessing histone deacetylase inhibition activity. Evidence from epidemiological and experimental studies have emerged, enhancing the clinical plausibility and translational value of sulforaphane in cancer chemoprevention. The present review provides the current understanding of the cancer chemopreventive pharmacology of sulforaphane towards its potential as an anticancer agent.

Acceptance and adherence to chemoprevention among women at increased risk of breast cancer.

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Roetzheim, Richard G; Lee, Ji-Hyun; Fulp, William; Matos Gomez, Elizabeth; Clayton, Elissa; Tollin, Sharon; Khakpour, Nazanin; Laronga, Christine; Lee, Marie Catherine; Kiluk, John V

2015-02-01

Chemoprevention is an option for women who are at increased risk of breast cancer (five year risk ≥1.7%). It is uncertain, however, how often women accept and complete five years of therapy and whether clinical or demographic factors predict completion. Medical records were abstracted for 219 women whose five year risk of breast cancer was ≥1.7% and who were offered chemoprevention while attending a high risk breast clinic at the Moffitt Cancer Center. We examined the likelihood of accepting chemoprevention and completing five years of therapy, and potential clinical and demographic predictors of these outcomes, using multivariable logistic regression and survival analysis models. There were 118/219 women (54.4%) who accepted a recommendation for chemoprevention and began therapy. The likelihood of accepting chemoprevention was associated with lifetime breast cancer risk and was higher for women with specific high risk conditions (lobular carcinoma in situ and atypical ductal hyperplasia). Women with osteoporosis and those that consumed alcohol were also more likely to accept medication. There were 58/118 (49.2%) women who stopped medication at least temporarily after starting therapy. Based on survival curves, an estimated 60% of women who begin chemoprevention will complete five years of therapy. A substantial percentage of women at increased risk of breast cancer will decline chemoprevention and among those that accept therapy, approximately 40% will not be able to complete five years of therapy because of side effects. Copyright © 2014 Elsevier Ltd. All rights reserved.

Arsenic and skin cancer – Case report with chemoprevention

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Uwe Wollina

2016-04-01

Full Text Available ABSTRACT Introduction: Arsenic is a potentially hazardous metalloid that can cause skin cancer. We want to demonstrate a case of chronic arsenicosis and the potential of chemoprevention with retinoids. Case Report: This is a case report of a 72-year-old male patient who was exposed to arsenics by dust and direct skin contact over 3 years in a chemical plant in the late fourties. He developed multiple arsenic keratosis clincialll resembling actinic keratoses, Bowen’s disease and palmar minute keratoses. To prevent a transformation into invasive cancer and to lower the burden of precancerous and in situ cancer lesions, he was treated orally with acitretin 20 mg/day. During 9 months of chemopreventive retinoid therapy a partial response of pre-existent skin lesions was noted. Treatment was well tolerated. During follow-up of 5 years no invasive malignancy developed. Conclusions: Intense exposure to arsenics during a relatively short period of 3 years bears a life-long health hazard with the delayed development of multiple in situ carcinomas and precancerous lesions. Chemoprevention with retinoids can induce a partial response.

Epigenetic Regulation by Sulforaphane: Opportunities for Breast and Prostate Cancer Chemoprevention.

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Atwell, Lauren L; Beaver, Laura M; Shannon, Jackilen; Williams, David E; Dashwood, Roderick H; Ho, Emily

2015-04-01

Sulforaphane (SFN) is a phytochemical derived from cruciferous vegetables that has multiple molecular targets and anti-cancer properties. Researchers have demonstrated several chemopreventive benefits of SFN consumption, such as reductions in tumor growth, increases in cancer cell apoptosis, and disruption of signaling within tumor microenvironments both in vitro and in vivo . Emerging evidence indicates that SFN exerts several of its chemopreventive effects by altering epigenetic mechanisms. This review summarizes evidence of the impact of SFN on epigenetic events and how they relate to the chemopreventive effects of SFN observed in preclinical and clinical studies of breast and prostate cancers. Specific areas of focus include the role of SFN in the regulation of cell cycle, apoptosis, inflammation, antioxidant defense, and cancer cell signaling and their relationships to epigenetic mechanisms. Finally, remaining challenges and research needs for translating mechanistic work with SFN into human studies and clinical intervention trials are discussed.

Phyto-oestrogens and breast cancer chemoprevention

International Nuclear Information System (INIS)

Limer, Jane L; Speirs, Valerie

2004-01-01

Phytoestrogens are polyphenol compounds of plant origin that exhibit a structural similarity to the mammalian steroid hormone 17β-oestradiol. In Asian nations the staple consumption of phyto-oestrogen-rich foodstuffs correlates with a reduced incidence of breast cancer. Human dietary intervention trials have noted a direct relationship between phyto-oestrogen ingestion and a favourable hormonal profile associated with decreased breast cancer risk. However, these studies failed to ascertain the precise effect of dietary phyto-oestrogens on the proliferation of mammary tissue. Epidemiological and rodent studies crucially suggest that breast cancer chemoprevention by dietary phyto-oestrogen compounds is dependent on ingestion before puberty, when the mammary gland is relatively immature. Phyto-oestrogen supplements are commercially marketed for use by postmenopausal women as natural and safe alternatives to hormone replacement therapy. Of current concern is the effect of phyto-oestrogen compounds on the growth of pre-existing breast tumours. Data are contradictory, with cell culture studies reporting both the oestrogenic stimulation of oestrogen receptor-positive breast cancer cell lines and the antagonism of tamoxifen activity at physiological phyto-oestrogen concentrations. Conversely, phyto-oestrogen ingestion by rodents is associated with the development of less aggressive breast tumours with reduced metastatic potential. Despite the present ambiguity, current data do suggest a potential benefit from use of phyto-oestrogens in breast cancer chemoprevention and therapy. These aspects are discussed

Chemoprevention of hormone-dependent prostate cancer in the Wistar-Unilever rat.

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McCormick, D L; Rao, K V

1999-01-01

The high incidence and long latent period of prostate cancer make it an ideal target for chemoprevention. We have evaluated a series of agents for chemopreventive efficacy using a model in which hormone-dependent prostate cancers are induced in the Wistar-Unilever (WU) rat by sequential treatment with antiandrogen (cyproterone acetate), androgen (testosterone propionate), and direct-acting chemical carcinogen (N-methyl-N-nitrosourea), followed by chronic androgen stimulation (testosterone). This regimen reproducibly induces prostate cancers in high incidence, with no gross toxicity and a low incidence of neoplasia in the seminal vesicle and other non-target tissues. Dehydroepiandrosterone (DHEA) and 9-cis-retinoic acid (9-cis-RA) are the most active agents identified to date. DHEA inhibits prostate cancer induction both when chronic administration is begun prior to carcinogen exposure, and when administration is delayed until preneoplastic prostate lesions are present. 9-cis-RA is the most potent inhibitor of prostate carcinogenesis identified; a study to determine the efficacy of delayed administration of 9-cis-RA is in progress. Liarozole fumarate confers modest protection against prostate carcinogenesis, while N-(4-hydroxyphenyl)retinamide (fenretinide), alpha-difluoromethylornithine, oltipraz, DL-alpha-tocopherol acetate (vitamin E), and L-selenomethionine are inactive. Chemoprevention efficacy evaluations in the WU rat will support the identification of agents that merit study for prostate cancer chemoprevention in humans.

Chemoprevention of prostate cancer: Natural compounds, antiandrogens, and antioxidants - In vivo evidence

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Nur Özten-Kandas

2011-01-01

Full Text Available Prostate cancer is the leading non-skin malignancy detected in US males and the second cause of death due to male cancer, in the US. Interventions with drugs or diet supplements that slow down the growth and progression of prostate cancer are potentially very effective in reducing the burden of prostate cancer, particularly if these treatments also prevent the de novo development of new prostatic malignancies. Challenges to identify efficacious agents and develop them for chemopreventive application in men at risk for prostate cancer have included uncertainty about which preclinical models have the ability to predict efficacy in men and lack of consensus about which early phase clinical trial designs are the most appropriate and cost-effective to test promising agents. Efficacy studies in animal models have identified several agents with potential chemopreventive activity against prostate cancer, but few of these findings have been translated into clinical trials. This article identifies some of the major issues associated with prostate cancer chemoprevention research and summarizes the most significant current results from animal efficacy studies and human clinical prevention trials. This summary focuses on: (1 Naturally occurring agents and compounds derived from such agents, including green tea and its constituents, silibinin and milk thistle, and genistein and soy, (2 chemoprevention drugs including agents interfering with androgen action, and (3 antioxidants such as selenium, vitamin E, and lycopene. The general lack of activity of antioxidants is discussed, followed by considerations about translation of preclinical chemoprevention efficacy data, focusing on dose, form, bioavailability, and timing of administration of the agent, as well as discussion of study design of clinical trials and the predictive ability of preclinical models.

Evaluating the potential cancer chemopreventive efficacy of two different solvent extracts of Seriphidium herba-alba in vitro

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Mahmoud Mohamed Mokhtar

2017-06-01

Full Text Available Cancer is the second leading cause of death world-wide. One of the most important medical practices of the 21st century is the chemoprevention of cancer. For a long history, it has been accepted that plants could prevent and exert suitable anti-carcinogenic effects for multiple types of cancers. Seriphidium herba-alba family Asteraceae has been used in the folk medicine by many cultures for treatment of various ailments since ancient times. In the current research we were aimed to evaluate the cancer chemopreventive activity of two crude extracts of S. herba-alba, methylene chloride extract and methanol extract on two cell lines: Human breast cancer cells (MCF-7 and human hepatocellular carcinoma cells (Hep-G2. Assessment of cytotoxicity using methyl thiazole tetrazolium (MTT assay indicated that both extracts exhibit poor cytotoxicity with half maximal inhibitory concentration (IC50 >20 µg/mL. Assessment of glutathione-S-transferases (GSTs activity (spectrophotometrically showed statistically significant enhancement of enzyme activity after treatment with three different doses of methylene chloride extract and glutathione (GSH concentrations were decreased. Analysis of cell mode of death by Ethidium bromide/Acridine orange (EB/AO staining revealed that the dominant mode of death in MCF-7 cells was apoptosis. Assessment of vascular endothelial growth factor (VEGF and platelets derived growth factor (PDGFBB using ELISA showed that VEGF and PDGFBB levels were statistically significant decreased. In Conclusion: both extracts may be cancer chemopreventive agents since they had tumor anti-initiating, and anti-promoting activity.

Colon cancer chemoprevention with ginseng and other botanicals.

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Wargovich, M J

2001-01-01

Colorectal cancer is becoming increasingly common in Asian countries and still remains the second leading cause of cancer deaths in the United States. Efforts to prevent colon cancer have targeted early detection through screening and chemoprevention. For the last ten years our laboratory has utilized an in vivo screening assay for the testing of potential cancer preventives for colon cancer. We have conducted investigations on over 150 compounds including many with botanical or herbal origin...

Cancer Chemopreventive Ability of Conjugated Linolenic Acids

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Kazuo Miyashita

2011-11-01

Full Text Available Conjugated fatty acids (CFA have received increased interest because of their beneficial effects on human health, including preventing cancer development. Conjugated linoleic acids (CLA are such CFA, and have been reviewed extensively for their multiple biological activities. In contrast to other types of CFAs including CLA that are found at low concentrations (less than 1% in natural products, conjugated linolenic acids (CLN are the only CFAs that occur in higher quantities in natural products. Some plant seeds contain a considerably high concentration of CLN (30 to 70 wt% lipid. Our research group has screened CLN from different plant seed oils to determine their cancer chemopreventive ability. This review describes the physiological functions of CLN isomers that occur in certain plant seeds. CLN are able to induce apoptosis through decrease of Bcl-2 protein in certain human cancer cell lines, increase expression of peroxisome proliferator-activated receptor (PPAR-γ, and up-regulate gene expression of p53. Findings in our preclinical animal studies have indicated that feeding with CLN resulted in inhibition of colorectal tumorigenesis through modulation of apoptosis and expression of PPARγ and p53. In this review, we summarize chemopreventive efficacy of CLN against cancer development, especially colorectal cancer.

Chemoprevention of Colorectal Cancer by Artocarpin, a Dietary Phytochemical from Artocarpus heterophyllus.

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Sun, Guochuan; Zheng, Zongping; Lee, Mee-Hyun; Xu, Yijuan; Kang, Soouk; Dong, Zigang; Wang, Mingfu; Gu, Zhennan; Li, Haitao; Chen, Wei

2017-05-03

Artocarpus heterophyllus is an evergreen tree distributed in tropical regions, and its fruit (jackfruit) is well-known as the world's largest tree-borne fruit. Although A. heterophyllus has been widely used in folk medicines against inflammation, its potential in cancer chemoprevention remains unclear. Herein we identified artocarpin from A. heterophyllus as a promising colorectal cancer chemopreventive agent by targeting Akt kinase. Phenotypically, artocarpin exhibited selective cytotoxicity against human colon cancer cells. Artocarpin impaired the anchorage-independent growth capability, suppressed colon cancer cell growth, and induced a G1 phase cell cycle arrest which was followed by apoptotic as well as autophagic cell death. Mechanistic studies revealed that artocarpin directly targeted Akt 1 and 2 kinase activity evidenced by in vitro kinase assay, ex vivo binding assay as well as Akt downstream cellular signal transduction. Importantly, oral administration of artocarpin attenuated colitis-associated colorectal tumorigenesis in mice. Taken together, artocarpin, a bioactive component of A. heterophyllus, might merit investigation as a potential colorectal cancer chemopreventive agent.

Cancer chemoprevention through dietary flavonoids: what's limiting?

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Amawi, Haneen; Ashby, Charles R; Tiwari, Amit K

2017-06-19

Flavonoids are polyphenols that are found in numerous edible plant species. Data obtained from preclinical and clinical studies suggest that specific flavonoids are chemo-preventive and cytotoxic against various cancers via a multitude of mechanisms. However, the clinical use of flavonoids is limited due to challenges associated with their effective use, including (1) the isolation and purification of flavonoids from their natural resources; (2) demonstration of the effects of flavonoids in reducing the risk of certain cancer, in tandem with the cost and time needed for epidemiological studies, and (3) numerous pharmacokinetic challenges (e.g., bioavailability, drug-drug interactions, and metabolic instability). Currently, numerous approaches are being used to surmount some of these challenges, thereby increasing the likelihood of flavonoids being used as chemo-preventive drugs in the clinic. In this review, we summarize the most important challenges and efforts that are being made to surmount these challenges.

Nutraceuticals for prostate cancer chemoprevention: from molecular mechanisms to clinical application.

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Wang, Zhijun; Fan, Jeffery; Liu, Mandy; Yeung, Steven; Chang, Andy; Chow, Moses S S; Pon, Doreen; Huang, Ying

2013-12-01

Nutraceutical is a food, or part of a food, used for the prevention and/or treatment of diseases. A number of nutraceuticals serve as candidates for development of prostate cancer chemopreventive agents because of promising epidemiological, preclinical and pilot clinical findings. Their mechanisms of action may involve an ability to target multiple molecular pathways in carcinogenesis without eliciting toxic side effects. This review provides an overview of several nutraceuticals, including green tea polyphenol, omega-3 fatty acids, vitamin D, lycopene, genistein, quercetin, resveratrol and sulforaphane, for the clinical relevance to chemoprevention of prostate cancer. Their mechanisms of action on regulating key processes of carcinogenesis are also discussed. For each of these agents, a brief summary of completed or currently ongoing clinical trials related to the chemopreventive efficacy on prostate cancer is given. Even though a few clinical trials have been conducted, review of these results indicate that further studies are required to confirm the clinical efficacy and safety, and to provide a guidance on how to use nutraceuticals for optimal effect. Future cancer prevention clinical trials for the nutraceuticals should recruit men with an increased risk of prostate cancer.

Combination chemoprevention with diclofenac, calcipotriol and difluoromethylornithine inhibits development of non-melanoma skin cancer in mice

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Pommergaard, Hans-Christian; Burcharth, Jakob; Rosenberg, Jacob

2013-01-01

Background/Aim: With increasing incidence of non-melanoma skin cancer (NMSC), focus on chemoprevention of this disease is growing. The aim of this study was to evaluate topical combination therapies as chemoprevention of UV radiation-induced tumors in a mouse model.......Background/Aim: With increasing incidence of non-melanoma skin cancer (NMSC), focus on chemoprevention of this disease is growing. The aim of this study was to evaluate topical combination therapies as chemoprevention of UV radiation-induced tumors in a mouse model....

Colorectal cancer chemoprevention: the potential of a selective approach.

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Ben-Amotz, Oded; Arber, Nadir; Kraus, Sarah

2010-10-01

Colorectal cancer (CRC) is a leading cause of cancer death, and therefore demands special attention. Novel recent approaches for the chemoprevention of CRC focus on selective targeting of key pathways. We review the study by Zhang and colleagues, evaluating a selective approach targeting APC-deficient premalignant cells using retinoid-based therapy and TNF-related apoptosis-inducing ligand (TRAIL). This study demonstrates that induction of TRAIL-mediated death signaling contributes to the chemopreventive value of all-trans-retinyl acetate (RAc) by sensitizing premalignant adenoma cells for apoptosis without affecting normal cells. We discuss these important findings, raise few points that deserve consideration, and may further contribute to the development of RAc-based combination therapies with improved efficacy. The authors clearly demonstrate a synergistic interaction between TRAIL, RAc and APC, which leads to the specific cell death of premalignant target cells. The study adds to the growing body of literature related to CRC chemoprevention, and provides solid data supporting a potentially selective approach for preventing CRC using RAc and TRAIL.

Preclinical Cancer Chemoprevention Studies Using Animal Model of Inflammation-Associated Colorectal Carcinogenesis

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Tanaka, Takuji [Cytopatholgy Division, Tohkai Cytopathology Institute, Cancer Research and Prevention (TCI-CaRP), 5-1-2 Minami-uzura, Gifu 500-8285 (Japan); Department of Tumor Pathology, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu 501-1194 (Japan)

2012-07-16

Inflammation is involved in all stages of carcinogenesis. Inflammatory bowel disease, such as ulcerative colitis and Crohn’s disease is a longstanding inflammatory disease of intestine with increased risk for colorectal cancer (CRC). Several molecular events involved in chronic inflammatory process are reported to contribute to multi-step carcinogenesis of CRC in the inflamed colon. They include over-production of free radicals, reactive oxygen and nitrogen species, up-regulation of inflammatory enzymes in arachidonic acid biosynthesis pathway, up-regulation of certain cytokines, and intestinal immune system dysfunction. In this article, firstly I briefly introduce our experimental animal models where colorectal neoplasms rapidly develop in the inflamed colorectum. Secondary, data on preclinical cancer chemoprevention studies of inflammation-associated colon carcinogenesis by morin, bezafibrate, and valproic acid, using this novel inflammation-related colorectal carcinogenesis model is described.

Lung Cancer Chemopreventive Activity of Patulin Isolated from Penicillium vulpinum

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Aymeric Monteillier

2018-03-01

Full Text Available Lung cancer is the most lethal form of cancer in the world. Its development often involves an overactivation of the nuclear factor kappa B (NF-κB pathway, leading to increased cell proliferation, survival, mobility, and a decrease in apoptosis. Therefore, NF-κB inhibitors are actively sought after for both cancer chemoprevention and therapy, and fungi represent an interesting unexplored reservoir for such molecules. The aim of the present work was to find naturally occurring lung cancer chemopreventive compounds by investigating the metabolites of Penicillium vulpinum, a fungus that grows naturally on dung. Penicillium vulpinum was cultivated in Potato Dextrose Broth and extracted with ethyl acetate. Bioassay-guided fractionation of this extract was performed by measuring NF-κB activity using a HEK293 cell line transfected with an NF-κB-driven luciferase reporter gene. The mycotoxin patulin was identified as a nanomolar inhibitor of TNF-α-induced NF-κB activity. Immunocytochemistry and Western blot analyses revealed that its mechanism of action involved an inhibition of p65 nuclear translocation and was independent from the NF-κB inhibitor α (IκBα degradation process. Enhancing its interest in lung cancer chemoprevention, patulin also exhibited antiproliferative, proapoptotic, and antimigration effects on human lung adenocarcinoma cells through inhibition of the Wnt pathway.

Comet Assay in Cancer Chemoprevention.

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Santoro, Raffaela; Ferraiuolo, Maria; Morgano, Gian Paolo; Muti, Paola; Strano, Sabrina

2016-01-01

The comet assay can be useful in monitoring DNA damage in single cells caused by exposure to genotoxic agents, such as those causing air, water, and soil pollution (e.g., pesticides, dioxins, electromagnetic fields) and chemo- and radiotherapy in cancer patients, or in the assessment of genoprotective effects of chemopreventive molecules. Therefore, it has particular importance in the fields of pharmacology and toxicology, and in both environmental and human biomonitoring. It allows the detection of single strand breaks as well as double-strand breaks and can be used in both normal and cancer cells. Here we describe the alkali method for comet assay, which allows to detect both single- and double-strand DNA breaks.

The strategies to control prostate cancer by chemoprevention approaches

International Nuclear Information System (INIS)

Ting, Harold; Deep, Gagan; Agarwal, Chapla; Agarwal, Rajesh

2014-01-01

Prostate cancer (PCA) is the most commonly diagnosed cancer in men in the United States with growing worldwide incidence. Despite intensive investment in improving early detection, PCA often escapes timely detection and mortality remains high; this malignancy being the second highest cancer-associated mortality in American men. Collectively, health care costs of PCA results in an immense financial burden that is only expected to grow. Additionally, even in cases of successful treatment, PCA is associated with long-term and pervasive effects on patients. A proactive alternative to treat PCA is to prevent its occurrence and progression prior to symptomatic malignancy. This may serve to address the issue of burgeoning healthcare costs and increasing number of sufferers. One potential regimen in service of this alternative is PCA chemoprevention. Here, chemical compounds with cancer preventive efficacy are identified on the basis of their potential in a host of categories: their historical medicinal use, correlation with reduced risk in population studies, non-toxicity, their unique chemical properties, or their role in biological systems. PCA chemopreventive agents are drawn from multiple broad classes of chemicals, themselves further subdivided based on source or potential effect, with most derived from natural products. Many such compounds have shown efficacy, varying from inhibiting deregulated PCA cell signaling, proliferation, epithelial to mesenchymal transition (EMT), invasion, metastasis, tumor growth and angiogenesis and inducing apoptosis. Overall, these chemopreventive agents show great promise in PCA pre-clinical models, though additional work remains to be done in effectively translating these findings into clinical use

Chemoprevention, chemotherapy, and chemoresistance in colorectal cancer.

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Marin, Jose J G; Sanchez de Medina, Fermin; Castaño, Beatriz; Bujanda, Luis; Romero, Marta R; Martinez-Augustin, Olga; Moral-Avila, Rosario Del; Briz, Oscar

2012-05-01

Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer-related death in industrialized countries. Chemoprevention is a promising approach, but studies demonstrating their usefulness in large populations are still needed. Among several compounds with chemopreventive ability, cyclooxygenase inhibitors have received particular attention. However, these agents are not without side effects, which must be weighed against their beneficial actions. Early diagnosis is critical in the management of CRC patients, because, in early stages, surgery is curative in >90% of cases. If diagnosis occurs at stages II and III, which is often the case, neoadjuvant chemotherapy and radiotherapy before surgery are, in a few cases, recommended. Because of the high risk of recurrence in advanced cancers, chemotherapy is maintained after tumor resection. Chemotherapy is also indicated when the patient has metastases and in advanced cancer located in the rectum. In the last decade, the use of anticancer drugs in monotherapy or in combined regimens has markedly increased the survival of patients with CRC at stages III and IV. Although the rate of success is higher than in other gastrointestinal tumors, adverse effects and development of chemoresistance are important limitations to pharmacological therapy. Genetic profiling regarding mechanisms of chemoresistance are needed to carry out individualized prediction of the lack of effectiveness of pharmacological regimens. This would minimize side effects and prevent the selection of aggressive, cross-resistant clones, as well as avoiding undesirable delays in the use of the most efficient therapeutic approaches to treat these patients.

Breast cancer chemopreventive and chemotherapeutic effects of Camellia Sinensis (green tea): an updated review.

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Rafieian-Kopaei, Mahmoud; Movahedi, Mino

2017-02-01

Camellia sinensis belongs to the plant family of Theaceae, native to East Asia, the Indian Subcontinent and Southeast Asia, but naturalized in many parts of the world. The aim of this study was to overview its anti-breast cancer chemopreventive and chemotherapeutic effects. This review article is aimed to overview breast cancer chemopreventive and chemotherapeutic effects of Camellia sinensis (green tea). This review article was carried out by searching studies in PubMed, Medline, Web of Science, and IranMedex databases. The initial search strategy identified around 108 references. In this study, 68 studies were accepted for further screening, and met all our inclusion criteria [in English, full text, chemopreventive and chemotherapeutic effects of Camellia sinensis and dated mainly from the year 1999 to 2016. The search terms were Camellia sinensis, chemopreventive, chemotherapeutic properties, pharmacological effects. The result of this study suggested that the catechin available in Camellia sinensis has properties which can prevent and treat breast cancer. It has also been shown to inhibit proliferation of breast cancer cells and to block carcinogenesis. It was found that increased Camellia sinensis consumption may lower the risk of breast cancer. Camellia sinensis intake was shown to reduce the risk of breast cancer incidence. In addition, potential breast cancer chemopreventive effect of Camellia sinensis both in vivo and in vitro was highly confirmed. However, the evidence of low effect and no effect was observed. More clinical trial studies are needed to prove its anti-breast cancer activity decisively. Camellia sinensis is broadly utilized as a part of customary medication since antiquated time because of its cost adequacy, and fewer reaction properties. The studies demonstrated anti-breast cancer activity of Camellia sinensis and its component by adjusting cell signaling pathways such as angiogenesis, apoptosis, and transcription factor. Furthermore

Prostate cancer chemoprevention in men of African descent: current state of the art and opportunities for future research.

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Chornokur, Ganna; Kumar, Nagi B

2013-08-01

Prostate cancer is the most frequently diagnosed malignancy in men. However, African American/Black men are 60 % more likely to be diagnosed with and 2.4 times more likely to die from prostate cancer, compared to Non-Hispanic White men. Despite the increased burden of this malignancy, no evidence-based recommendation regarding prostate cancer screening exists for the high-risk population. Moreover, in addition to screening and detection, African American men may constitute a prime population for chemoprevention. Early detection and chemoprevention may thus represent an integral part of prostate cancer control in this population. Importantly, recent research has elucidated biological differences in the prostate tumors of African American compared to European American men. The latter may enable a more favorable response in African American men to specific chemopreventive agents that target relevant signal transduction pathways. Based on this evolving evidence, the aims of this review are threefold. First, we aim to summarize the biological differences that were reported in the prostate tumors of African American and European American men. Second, we will review the single- and multi-target chemopreventive agents placing specific emphasis on the pathways implicated in prostate carcinogenesis. And lastly, we will discuss the most promising nutraceutical chemopreventive compounds. Our review underscores the promise of chemoprevention in prostate cancer control, as well as provides justification for further investment in this filed to ultimately reduce prostate cancer morbidity and mortality in this high-risk population of African American men.

Curcumin and metformin-mediated chemoprevention of oral cancer is associated with inhibition of cancer stem cells.

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Siddappa, Gangotri; Kulsum, Safeena; Ravindra, Doddathimmasandra Ramanjanappa; Kumar, Vinay V; Raju, Nalini; Raghavan, Nisheena; Sudheendra, Holalugunda Vittalamurthy; Sharma, Anupam; Sunny, Sumsum P; Jacob, Tina; Kuruvilla, Binu T; Benny, Merina; Antony, Benny; Seshadri, Mukund; Lakshminarayan, Padma; Hicks, Wesley; Suresh, Amritha; Kuriakose, Moni A

2017-11-01

Effective chemoprevention is critical for improving outcomes of oral cancer. As single agents, curcumin and metformin are reported to exhibit chemopreventive properties, in vitro as well as in patients with oral cancer. In this study, the chemopreventive efficacy of this drug combination was tested in a 4-nitro quinoline-1-oxide (4NQO) induced mice oral carcinogenesis model. Molecular analysis revealed a cancer stem cell (CSC)-driven oral carcinogenic progression in this model, wherein a progressive increase in the expression of CSC-specific markers (CD44 and CD133) was observed from 8th to 25th week, at transcript (40-100-fold) and protein levels (P ≤ 0.0001). Chemopreventive treatment of the animals at 17th week with curcumin and metformin indicated that the combination regimen decreased tumor volume when compared to the control arm (0.69+0.03 vs 6.66+2.4 mm 3 ; P = 0.04) and improved overall survival of the animals (P = 0.03). Assessment of the molecular status showed an overall downregulation of CSC markers in the treatment arms as compared to the untreated control. Further, in vitro assessment of the treatment on the primary cells generated from progressive stages of 4NQO-induced mice tissue showed a concordant and consistent downregulation of the CSC markers following combination treatment (P oral squamous cell carcinoma through a CSC-associated mechanism. © 2017 Wiley Periodicals, Inc.

Overview of mechanisms of cancer chemopreventive agents

International Nuclear Information System (INIS)

De Flora, Silvio; Ferguson, Lynnette R.

2005-01-01

Epidemiological data provide evidence that it is possible to prevent cancer and other chronic diseases, some of which share common pathogenetic mechanisms, such as DNA damage, oxidative stress, and chronic inflammation. An obvious approach is avoidance of exposure to recognized risk factors. As complementary strategies, it is possible to render the organism more resistant to mutagens/carcinogens and/or to inhibit progression of the disease by administering chemopreventive agents. In a primary prevention setting, addressed to apparently healthy individuals, it is possible to inhibit mutation and cancer initiation by triggering protective mechanisms either in the extracellular environment or inside cells, e.g., by modifying transmembrane transport, modulating metabolism, blocking reactive species, inhibiting cell replication, maintaining DNA structure, modulating DNA metabolism and repair, and controlling gene expression. Tumor promotion can be counteracted by inhibiting genotoxic effects, favoring antioxidant and anti-inflammatory activity, inhibiting proteases and cell proliferation, inducing cell differentiation, modulating apoptosis and signal transduction pathways, and protecting intercellular communications. In a secondary prevention setting, when a premalignant lesion has been detected, it is possible to inhibit tumor progression via the same mechanisms, and in addition by affecting the hormonal status and the immune system in various ways, and by inhibiting tumor angiogenesis. Although tertiary prevention, addressed to cancer patients after therapy, is outside the classical definition of chemoprevention, it exploits similar mechanisms. It is also possible to affect cell-adhesion molecules, to activate antimetastasis genes, and to inhibit proteases involved in basement membrane degradation

Curcumin and Other Polyphenolic Compounds in Head and Neck Cancer Chemoprevention

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Philipp Baumeister

2012-01-01

Full Text Available Despite clear results of observational studies linking a diet rich in fruits and vegetables to a decreased cancer risk, large interventional trials evaluating the impact of dietary micronutrient supplementation, mostly vitamins, could not show any beneficial effects. Today it has become clear that a single micronutrient, given in supernutritional doses, cannot match cancer preventive effects of whole fruits and vegetables. In this regard polyphenols came into focus, not only because of their antioxidant potential but also because of their ability to interact with molecular targets within the cells. Because polyphenols occur in many foods and beverages in high concentration and evidence for their anticancer activity is best for tissues they can come into direct contact with, field cancerization predestines upper aerodigestive tract epithelium for cancer chemoprevention by polyphenols. In this paper, we summarize cancer chemopreventive attempts with emphasis on head and neck carcinogenesis and discuss some methodological issues. We present data regarding antimutagenic effects of curcumin and epigallocatechin-3-gallate in human oropharyngeal mucosa cultures exposed to cigarette smoke condensate.

Cancer Chemoprevention by Traditional Chinese Herbal Medicine and Dietary Phytochemicals: Targeting Nrf2-Mediated Oxidative Stress/Anti-Inflammatory Responses, Epigenetics, and Cancer Stem Cells

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Jong Hun Lee

2013-01-01

Full Text Available Excessive oxidative stress induced by reactive oxygen species (ROS, reactive nitrogen species (RNS, and reactive metabolites of carcinogens alters cellular homeostasis, leading to genetic/epigenetic changes, genomic instability, neoplastic transformation, and cancer initiation/progression. As a protective mechanism against oxidative stress, antioxidant/detoxifying enzymes reduce these reactive species and protect normal cells from endo-/exogenous oxidative damage. The transcription factor nuclear factor-erythroid 2 p45 (NF-E2-related factor 2 (Nrf2, a master regulator of the antioxidative stress response, plays a critical role in the expression of many cytoprotective enzymes, including NAD(PH:quinine oxidoreductase (NQO1, heme oxygenase-1 (HO-1, UDP-glucuronosyltransferase (UGT, and glutathione S-transferase (GST. Recent studies demonstrated that many dietary phytochemicals derived from various vegetables, fruits, spices, and herbal medicines induce Nrf2-mediated antioxidant/detoxifying enzymes, restore aberrant epigenetic alterations, and eliminate cancer stem cells (CSCs. The Nrf2-mediated antioxidant response prevents many age-related diseases, including cancer. Owing to their fundamental contribution to carcinogenesis, epigenetic modifications and CSCs are novel targets of dietary phytochemicals and traditional Chinese herbal medicine (TCHM. In this review, we summarize cancer chemoprevention by dietary phytochemicals, including TCHM, which have great potential as a safer and more effective strategy for preventing cancer.

Chemoprevention of cancer: an ongoing saga.

Science.gov (United States)

Kellen, J A

1999-01-01

The trivial adage "an ounce of prevention..." is certainly appropriate in oncology; cancer has and continues to have an enormous impact on morbidity, suffering, socioeconomics and mortality. Curative therapy is elusive--cancer remains a mainly lethal disease, which makes the objective of prevention even more important and attractive. Sober estimates put the potentially avoidable or preventable cancers in the Western World at 80% (1): the effects of smoking and alcohol, being overweight, diet promiscuity and other lifestyle choices are well known, yet at the individual level, corrective measures are disappointingly ignored. Lately, this issue is being further weakened by our acceptance of inherited susceptibility--why change our habits and indulgences, if we can not escape our genetic destiny? However, there is a massive and growing amount of information on chemoprevention which needs to be carefully evaluated, in the hope that someday, we should be able to avoid or at least delay cancer by the use of natural or synthetic compounds which intervene in the early precancerous process.

Targeting Chemoprevention of Colorectal Cancer to Those Who Are Likely to Respond

OpenAIRE

Stockbrugger, Reinhold W.

2010-01-01

In the past four decades, chemoprevention of colorectal cancer (CRC) has been the subject of many epidemiologic and intervention trials of naturally occurring or pharmacologic agents. Recently, the positioning of cyclooxygenase 2 inhibitors as a viable option in this context was a major breakthrough; however, it was hampered by adverse cardiovascular events. This review questions whether chemopreventive measures for CRC are ready to be used in mass or individual applications, standing alone o...

New Enlightenment of Skin Cancer Chemoprevention through Phytochemicals: In Vitro and In Vivo Studies and the Underlying Mechanisms.

Science.gov (United States)

Singh, Madhulika; Suman, Shankar; Shukla, Yogeshwer

2014-01-01

Skin cancer is still a major cause of morbidity and mortality worldwide. Skin overexposure to ultraviolet irradiations, chemicals, and several viruses has a capability to cause severe skin-related disorders including immunosuppression and skin cancer. These factors act in sequence at various steps of skin carcinogenesis via initiation, promotion, and/or progression. These days cancer chemoprevention is recognized as the most hopeful and novel approach to prevent, inhibit, or reverse the processes of carcinogenesis by intervention with natural products. Phytochemicals have antioxidant, antimutagenic, anticarcinogenic, and carcinogen detoxification capabilities thereby considered as efficient chemopreventive agents. Considerable efforts have been done to identify the phytochemicals which may possibly act on one or several molecular targets that modulate cellular processes such as inflammation, immunity, cell cycle progression, and apoptosis. Till date several phytochemicals in the light of chemoprevention have been studied by using suitable skin carcinogenic in vitro and in vivo models and proven as beneficial for prevention of skin cancer. This revision presents a comprehensive knowledge and the main molecular mechanisms of actions of various phytochemicals in the chemoprevention of skin cancer.

New Enlightenment of Skin Cancer Chemoprevention through Phytochemicals: In Vitro and In Vivo Studies and the Underlying Mechanisms

Directory of Open Access Journals (Sweden)

Madhulika Singh

2014-01-01

Full Text Available Skin cancer is still a major cause of morbidity and mortality worldwide. Skin overexposure to ultraviolet irradiations, chemicals, and several viruses has a capability to cause severe skin-related disorders including immunosuppression and skin cancer. These factors act in sequence at various steps of skin carcinogenesis via initiation, promotion, and/or progression. These days cancer chemoprevention is recognized as the most hopeful and novel approach to prevent, inhibit, or reverse the processes of carcinogenesis by intervention with natural products. Phytochemicals have antioxidant, antimutagenic, anticarcinogenic, and carcinogen detoxification capabilities thereby considered as efficient chemopreventive agents. Considerable efforts have been done to identify the phytochemicals which may possibly act on one or several molecular targets that modulate cellular processes such as inflammation, immunity, cell cycle progression, and apoptosis. Till date several phytochemicals in the light of chemoprevention have been studied by using suitable skin carcinogenic in vitro and in vivo models and proven as beneficial for prevention of skin cancer. This revision presents a comprehensive knowledge and the main molecular mechanisms of actions of various phytochemicals in the chemoprevention of skin cancer.

Preclinical renal cancer chemopreventive efficacy of geraniol by modulation of multiple molecular pathways

International Nuclear Information System (INIS)

Ahmad, Shiekh Tanveer; Arjumand, Wani; Seth, Amlesh; Nafees, Sana; Rashid, Summya; Ali, Nemat; Sultana, Sarwat

2011-01-01

Graphical abstract: Diagrammatic presentation of the hypothesis of the article in a concise manner. It reveals the chemopreventive efficacy of GOH possibly through the modulation of multiple molecular targets. GOH inhibits ROS generation, NFκB and PCNA expression thereby abrogating inflammation and proliferation of tubular cells of kidney. Whereas, GOH induces effector caspase-3 expression both through mitochondrial signalling pathway and death receptor signalling pathway. Highlights: → Geraniol modulates renal carcinogenesis in Wistar rats. → It abrogates Fe-NTA induced oxidative stress, inflammation and hyperproliferation. → Promotes apoptosis via induction of both mitochondrial and death receptor pathway. → Thus, inhibits renal carcinogenesis by modulating multiple molecular targets. -- Abstract: In the present study, we have evaluated the chemopreventive potential of geraniol (GOH), an acyclic monoterpene alcohol against ferric nitrilotriacetate (Fe-NTA) induced renal oxidative stress and carcinogenesis in Wistar rats. Chronic treatment of Fe-NTA induced oxidative stress, inflammation and cellular proliferation in Wistar rats. The chemopreventive efficacy of GOH was studied in terms of xenobiotic metabolizing enzyme activities, LPO, redox status, serum toxicity markers and the expression of putative nephrotoxicity biomarker Kim-1, tumor suppressor gene P53, inflammation, cell proliferation and apoptosis related genes in the kidney tissue. Oral administration of GOH at doses of 100 and 200 mg/kg b wt effectively suppressed renal oxidative stress and tumor incidence. Chemopreventive effects of GOH were associated with upregulation of xenobiotic metabolizing enzyme activities and down regulation of serum toxicity markers. GOH was able to down regulate expression of Kim-1, NFκB, PCNA, P53 along with induction of apoptosis. However, higher dose of GOH was more effective in modulating these multiple molecular targets both at transcriptional and protein

Null activity of selenium and vitamin e as cancer chemopreventive agents in the rat prostate.

Science.gov (United States)

McCormick, David L; Rao, K V N; Johnson, William D; Bosland, Maarten C; Lubet, Ronald A; Steele, Vernon E

2010-03-01

To evaluate the potential efficacy of selenium and vitamin E as inhibitors of prostate carcinogenesis, four chemoprevention studies using a common protocol were done in a rat model of androgen-dependent prostate cancer. After stimulation of prostate epithelial cell proliferation by a sequential regimen of cyproterone acetate followed by testosterone propionate, male Wistar-Unilever rats received a single i.v. injection of N-methyl-N-nitrosourea (MNU) followed by chronic androgen stimulation via subcutaneous implantation of testosterone pellets. At 1 week post-MNU, groups of carcinogen-treated rats (39-44/group) were fed either a basal diet or a basal diet supplemented with l-selenomethionine (3 or 1.5 mg/kg diet; study 1), dl-alpha-tocopherol (vitamin E, 4,000 or 2,000 mg/kg diet; study 2), l-selenomethionine + vitamin E (3 + 2,000 mg/kg diet or 3 + 500 mg/kg diet; study 3), or selenized yeast (target selenium levels of 9 or 3 mg/kg diet; study 4). Each chemoprevention study was terminated at 13 months post-MNU, and prostate cancer incidence was determined by histopathologic evaluation. No statistically significant reductions in prostate cancer incidence were identified in any group receiving dietary supplementation with selenium and/or vitamin E. These data do not support the hypotheses that selenium and vitamin E are potent cancer chemopreventive agents in the prostate, and when considered with the recent clinical data reported in the Selenium and Vitamin E Cancer Prevention Trial (SELECT), show the predictive nature of this animal model for human prostate cancer chemoprevention.

Tea: age-old beverage as an effective cancer chemopreventive agent

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Jasmine George

2011-12-01

Full Text Available Cancer is the major public health problem, causing approximately 7 million deaths every year worldwide. The existing treatment approaches and surgical techniques have not been able to cope effectively with this dreaded disease. Because of this, the concept of chemoprevention is now considered a valid approach to reduce the incidence of cancer. There is convincing epidemiological and experimental evidence to show that dietary polyphenolic plant-derived compounds have cancer preventive properties. Based on evidence from in vitro, in vivo data and epidemiological studies, tea has received considerable attention over recent years for reducing the risk of several cancers. Much of the cancer preventive effects of tea, and in particular green tea, appear to be mediated by the polyphenols they contain. In addition to inhibiting mutagenesis and proliferation, tea is relatively non-toxic, is low cost, and can be taken orally or as a part of the daily diet. Therefore it is logical that future clinical studies should focus on examining the efficacy of tea and its active constituents, such as epigallocatechin- 3-gallate (EGCG and theaflavins (TFs, in chemoprevention as an alternative to pharmacological agents. In this review, we address the use of tea and its constituents for the prevention and treatment of cancer. Further mechanistic and dose-response studies will help us to understand the effects of tea consumption on human carcinogenesis.

Colon Cancer Chemoprevention by Sage Tea Drinking: Decreased DNA Damage and Cell Proliferation.

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Pedro, Dalila F N; Ramos, Alice A; Lima, Cristovao F; Baltazar, Fatima; Pereira-Wilson, Cristina

2016-02-01

Salvia officinalis and some of its isolated compounds have been found to be preventive of DNA damage and increased proliferation in vitro in colon cells. In the present study, we used the azoxymethane model to test effects of S. officinalis on colon cancer prevention in vivo. The results showed that sage treatment reduced the number of ACF formed only if administered before azoxymethane injection, demonstrating that sage tea drinking has a chemopreventive effect on colorectal cancer. A decrease in the proliferation marker Ki67 and in H2 O2 -induced and azoxymethane-induced DNA damage to colonocytes and lymphocytes were found with sage treatment. This confirms in vivo the chemopreventive effects of S. officinalis. Taken together, our results show that sage treatment prevented initiation phases of colon carcinogenesis, an effect due, at least in part, to DNA protection, and reduced proliferation rates of colon epithelial cell that prevent mutations and their fixation through cell replication. These chemopreventive effects of S. officinalis on colon cancer add to the many health benefits attributed to sage and encourage its consumption. Copyright © 2015 John Wiley & Sons, Ltd.

Drug delivery strategies for chemoprevention of UVB-induced skin cancer: A review.

Science.gov (United States)

Bagde, Arvind; Mondal, Arindam; Singh, Mandip

2018-01-01

Annually, more skin cancer cases are diagnosed than the collective incidence of the colon, lung, breast, and prostate cancer. Persistent contact with sunlight is a primary cause for all the skin malignancies. UVB radiation induces reactive oxygen species (ROS) production in the skin which eventually leads to DNA damage and mutation. Various delivery approaches for the skin cancer treatment/prevention have been evolving and are directed toward improvements in terms of delivery modes, therapeutic agents, and site-specificity of therapeutics delivery. The effective chemoprevention activity achieved is based on the efficiency of the delivery system used and the amount of the therapeutic molecule deposited in the skin. In this article, we have discussed different studies performed specifically for the chemoprevention of UVB-induced skin cancer. Ultra-flexible nanocarriers, transethosomes nanocarriers, silica nanoparticles, silver nanoparticles, nanocapsule suspensions, microemulsion, nanoemulsion, and polymeric nanoparticles which have been used so far to deliver the desired drug molecule for preventing the UVB-induced skin cancer. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Moringa oleifera Lam: Targeting Chemoprevention.

Science.gov (United States)

Karim, Nurul Ashikin Abd; Ibrahim, Muhammad Din; Kntayya, Saie Brindha; Rukayadi, Yaya; Hamid, Hazrulizawati Abd; Razis, Ahmad Faizal Abdull

2016-01-01

Moringa oleifera Lam, family Moringaceae, is a perennial plant which is called various names, but is locally known in Malaysia as "murungai" or "kelor". Glucomoringin, a glucosinolate with from M. oleifera is a major secondary metabolite compound. The seeds and leaves of the plant are reported to have the highest amount of glucosinolates. M. oleifera is well known for its many uses health and benefits. It is claimed to have nutritional, medicinal and chemopreventive potentials. Chemopreventive effects of M. oleifera are expected due to the existence of glucosinolate which it is reported to have the ability to induce apoptosis in anticancer studies. Furthermore, chemopreventive value of M. oleifera has been demonstrated in studies utilizing its leaf extract to inhibit the growth of human cancer cell lines. This review highlights the advantages of M. oleifera targeting chemoprevention where glucosinolates could help to slow the process of carcinogenesis through several molecular targets. It is also includes inhibition of carcinogen activation and induction of carcinogen detoxification, anti-inflammatory, anti-tumor cell proliferation, induction of apoptosis and inhibition of tumor angiogenesis. Finally, for synergistic effects of M. oleifera with other drugs and safety, essential for chemoprevention, it is important that it safe to be consumed by human body and works well. Although there is promising evidence about M. oleifera in chemoprevention, extensive research needs to be done due to the expected rise of cancer in coming years and to gain more information about the mechanisms involved in M. oleifera influence, which could be a good source to inhibit several major mechanisms involved in cancer development.

Targeting Chemoprevention of Colorectal Cancer to Those Who Are Likely to Respond.

Science.gov (United States)

Stockbrugger, Reinhold W

2010-01-01

In the past four decades, chemoprevention of colorectal cancer (CRC) has been the subject of many epidemiologic and intervention trials of naturally occurring or pharmacologic agents. Recently, the positioning of cyclooxygenase 2 inhibitors as a viable option in this context was a major breakthrough; however, it was hampered by adverse cardiovascular events. This review questions whether chemopreventive measures for CRC are ready to be used in mass or individual applications, standing alone or in combination with other CRC-preventive measures. It also discusses steps that may be undertaken to explore this field further.

Chemoprevention of Lung Cancer: Prospects and Disappointments in Human Clinical Trials

Directory of Open Access Journals (Sweden)

William N. Rom

2013-01-01

Full Text Available Decreasing the risk of lung cancer, or preventing its development in high-risk individuals, would have a huge impact on public health. The most effective means to decrease lung cancer incidence is to eliminate exposure to carcinogens. However, with recent advances in the understanding of pulmonary carcinogenesis and the identification of intermediate biomarkers, the prospects for the field of chemoprevention research have improved dramatically. Here we review the most recent research in lung cancer chemoprevention—focusing on those agents that have been investigated in human clinical trials. These agents fall into three major categories. First, oxidative stress plays an important role in pulmonary carcinogenesis; and therefore, antioxidants (including vitamins, selenium, green tea extracts, and isothiocyanates may be particularly effective in preventing the development of lung cancer. Second, inflammation is increasingly accepted as a crucial factor in carcinogenesis, and many investigators have focused on anti-inflammatory agents, such as glucocorticoids, NSAIDs, statins, and PPARγ agonists. Finally, the PI3K/AKT/mTOR pathway is recognized to play a central role in tobacco-induced carcinogenesis, and inhibitors of this pathway, including myoinositol and metformin, are promising agents for lung cancer prevention. Successful chemoprevention will likely require targeting of multiple pathways to carcinogenesis—both to minimize toxicity and maximize efficacy.

Regulatory approval of cancer risk-reducing (chemopreventive) drugs: moving what we have learned into the clinic.

Science.gov (United States)

Meyskens, Frank L; Curt, Gregory A; Brenner, Dean E; Gordon, Gary; Herberman, Ronald B; Finn, Olivera; Kelloff, Gary J; Khleif, Samir N; Sigman, Caroline C; Szabo, Eva

2011-03-01

This article endeavors to clarify the current requirements and status of regulatory approval for chemoprevention (risk reduction) drugs and discusses possible improvements to the regulatory pathway for chemoprevention. Covering a wide range of topics in as much depth as space allows, this report is written in a style to facilitate the understanding of nonscientists and to serve as a framework for informing the directions of experts engaged more deeply with this issue. Key topics we cover here are as follows: a history of definitive cancer chemoprevention trials and their influence on the evolution of regulatory assessments; a brief review of the long-standing success of pharmacologic risk reduction of cardiovascular diseases and its relevance to approval for cancer risk reduction drugs; the use and limitations of biomarkers for developing and the approval of cancer risk reduction drugs; the identification of individuals at a high(er) risk for cancer and who are appropriate candidates for risk reduction drugs; business models that should incentivize pharmaceutical industry investment in cancer risk reduction; a summary of scientific and institutional barriers to development of cancer risk reduction drugs; and a summary of major recommendations that should help facilitate the pathway to regulatory approval for pharmacologic cancer risk reduction drugs.

Recruitment strategies for a lung cancer chemoprevention trial involving ex-smokers.

Science.gov (United States)

Kye, Steve H; Tashkin, Donald P; Roth, Michael D; Adams, Bradley; Nie, Wen-Xian; Mao, Jenny T

2009-09-01

The ability to recruit qualified subjects who are willing to adhere to the study protocol in clinical trials is an essential component of translational research. Such tasks can be particularly challenging for chemoprevention studies when the targeted study population is healthy, at risk individuals who do not have signs or symptoms of the disease, and the study participation involves complex scheduling and invasive procedures such as bronchoscopy. In this report, we describe the recruitment process and evaluated the effectiveness of various recruitment strategies utilized in our National Cancer Institute sponsored lung cancer chemoprevention study with celecoxib. Heavy ex-smokers were recruited into the study through various methods such as radio advertisements, print media, mass mailings, flyers, internet postings and others. The number of inquiries, on-site screenees and randomization generated by each method determined the efficacy of that recruitment strategy. We prescreened 4470 individuals, invited 323 people for on-site screening and randomized 137 subjects. Radio advertisements (ads) generated the most inquiries (71.1%), followed by internet posting (11.8%), print media (6.0%), posted and racked flyers (4.4%), mass mailings (2.7%) and other strategies such as referrals from friends or family members or health care providers (2.3%). Radio ads, although costly, yielded the most subjects for on-site screening and randomization. Moreover, among the various types of radio stations, news radio stations were by far the most successful. Our results suggest that advertising on news radio is a highly effective recruitment method for successful accrual of ex-smokers into lung cancer chemoprevention trials.

Endotoxin and cancer chemo-prevention.

Science.gov (United States)

Mastrangelo, Giuseppe; Fadda, Emanuela; Cegolon, Luca

2013-10-01

Reduced rates of lung cancer have been observed in several occupational groups exposed to high levels of organic dusts contaminated by endotoxin. The underlying anti-neoplastic mechanism of endotoxin may be an increased secretion of endogenous anti-neoplastic mediators and activation of the toll-like receptors (TLR). A detoxified endotoxin derivative, Monophosphoryl Lipid A (MPL(®)) is marketed in Europe since 1999 as part of the adjuvant systems in allergy vaccines for treatment of allergic rhino-conjunctivitis and allergic asthma. Over 200,000 patients have used them to date (nearly 70% in Germany). Since detailed exposure (MPL(®) dose and timing of administration) and individual data are potentially available, an observational follow-up study could be conducted in Germany to investigate the protective effect of MPL(®) against cancer, comparing cancer incidence in two groups of patients with allergic rhinitis: those treated with allergoids plus MPL(®) and those treated with a vaccine including the same allergoids but not MPL(®). The protective effect of MPL(®) could be quantified in ever and never smokers. If this proposed observational study provides evidence of protective effects, MPL(®) could be immediately used as a chemo-preventive agent since it is already in use as adjuvant in human vaccines against cancer. Copyright © 2013 Elsevier Ltd. All rights reserved.

A Review of Promising Natural Chemopreventive Agents for Head and Neck Cancer.

Science.gov (United States)

Crooker, Kyle; Aliani, Rana; Ananth, Megha; Arnold, Levi; Anant, Shrikant; Thomas, Sufi Mary

2018-03-30

Head and neck squamous cell carcinoma (HNSCC) accounts for 300,000 deaths per year worldwide and overall survival rates have shown little improvement over the past three decades. Current treatment methods including surgery, chemotherapy, and radiotherapy leave patients with secondary morbidities. Thus, treatment of HNSCC may benefit from exploration of natural compounds as chemopreventive agents. With excellent safety profiles, reduced toxicities, antioxidant properties, and general acceptance for use as dietary supplements, natural compounds are viewed as a desirable area of investigation for chemoprevention. Though most of the field is early in development, numerous studies display the potential utility of natural compounds against HNSCC. These compounds face additional challenges such as low bioavailability for systemic delivery, potential toxicities when consumed in pharmacological doses, and acquired resistance. However, novel delivery vehicles and synthetic analogs have shown overcome some of these challenges. This review covers eleven promising natural compounds in the chemoprevention of HNSCC including vitamin A, curcumin, isothiocyanate, green tea, luteolin, resveratrol, genistein, lycopene, bitter melon, withaferin A, and guggulsterone. The review discusses the therapeutic potential and associated challenges of these agents in the chemopreventive efforts against HNSCC. Copyright ©2018, American Association for Cancer Research.

Effect of Proton Beam on Cancer Progressive and Metastatic Enzymes

International Nuclear Information System (INIS)

Sohn, Y. H.; Nam, K. S.; Oh, Y. H.; Kim, M. K.; Kim, M. Y.; Jang, J. S.

2008-04-01

The purpose of this study was to investigate the effect of proton beam on enzymes for promotion/progression of carcinogenesis and metastasis of malignant tumor cells to clarify proton beam-specific biological effects. The changes of cancer chemopreventive enzymes in human colorectal adenocarcinoma HT-29 cells irradiated with proton beams were tested by measuring the activities of quinine reductase (QR), glutathione S-transferase (GST), and ornithine decarboxylase (ODC), glutathione (GSH) levels, and expression of cyclooxygenase-2 (COX-2). We also examined the effect of proton beam on the ODC activity and expression of COX-2 in human breast cancer cell. We then assessed the metastatic capabilities of HT-29 and MDA-MB-231 cells irradiated with proton beam by measuring the invasiveness of cells through Matrigel-coated membrane and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced MMP activity in MDA-MB-231 and HT-29 cells. QR activity of irradiated HT-29 cells was slightly increased. Proton irradiation at dose of 32 Gy in HT-29 cells increased GST activity by 1.23-fold. In addition GSH levels in HT-29 cells was significantly increased 1.23- (p<0.05), 1.32- (p<0.01) and 1.34-fold (p<0.01) with the proton irradiation at doses of 8, 16 and 32 Gy, respectively. These results suggest that colon cancer chemopreventive activity was increased with the proton irradiation by increasing QR and GST activities and GSH levels and inhibiting ODC activity. Proton ion irradiation decreased the invasiveness of TPA-treated HT-29 cells and MDA-MB-231 cells through Matrigel-coated membrane. Proton ion irradiation pretreatment decreased TPA-induced MMP activity in MDA-MB-231 and HT-29 cells. Further studies are necessary to investigate if these findings could be translated to in vivo situations

Cyclooxygenase as a target for chemoprevention in colorectal cancer: lost cause or a concept coming of age?

LENUS (Irish Health Repository)

Doherty, Glen A

2009-02-01

COX-2 is upregulated at an early stage in colorectal carcinogenesis and generates prostaglandins, which promote cancer cell proliferation, impair apoptosis and enhance angiogenesis, promoting tumour growth and metastasis. There are ample data from animal models and human studies to demonstrate enhanced tumour progression associated with COX-2 activity in cancer cells. Conversely, NSAIDs including aspirin inhibit COX-2 and, therefore, have anti-neoplastic properties. There has been sustained interest in COX-2 as a chemopreventive target in colorectal cancer (CRC) and although both aspirin and COX-2 selective NSAIDs have demonstrated efficacy, adverse effects have limited their widespread adoption. In particular, evidence of the cardiovascular effects of COX-2 selective inhibitors has led to questioning of the suitability of COX-2 as a target for chemoprevention. This review examines the basis for targeting COX-2 in CRC chemoprevention, evaluates the efficacy and safety of the approach and examines future strategies in this area.

Combination chemoprevention with grape antioxidants.

Science.gov (United States)

Singh, Chandra K; Siddiqui, Imtiaz A; El-Abd, Sabah; Mukhtar, Hasan; Ahmad, Nihal

2016-06-01

Antioxidant ingredients present in grape have been extensively investigated for their cancer chemopreventive effects. However, much of the work has been done on individual ingredients, especially focusing on resveratrol and quercetin. Phytochemically, whole grape represents a combination of numerous phytonutrients. Limited research has been done on the possible synergistic/additive/antagonistic interactions among the grape constituents. Among these phytochemical constituents of grapes, resveratrol, quercetin, kaempferol, catechin, epicatechin, and anthocyanins (cyanidin and malvidin) constitute more than 70% of the grape polyphenols. Therefore, these have been relatively well studied for their chemopreventive effects against a variety of cancers. While a wealth of information is available individually on cancer chemopreventive/anti-proliferative effects of resveratrol and quercetin, limited information is available regarding the other major constituents of grape. Studies have also suggested that multiple grape antioxidants, when used in combination, alone or with other agents/drugs show synergistic or additive anti-proliferative response. Based on strong rationale emanating from published studies, it seems probable that a combination of multiple grape ingredients alone or together with other agents could impart 'additive synergism' against cancer. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nanoencapsulation of pomegranate bioactive compounds for breast cancer chemoprevention.

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Shirode, Amit B; Bharali, Dhruba J; Nallanthighal, Sameera; Coon, Justin K; Mousa, Shaker A; Reliene, Ramune

2015-01-01

Pomegranate polyphenols are potent antioxidants and chemopreventive agents but have low bioavailability and a short half-life. For example, punicalagin (PU), the major polyphenol in pomegranates, is not absorbed in its intact form but is hydrolyzed to ellagic acid (EA) moieties and rapidly metabolized into short-lived metabolites of EA. We hypothesized that encapsulation of pomegranate polyphenols into biodegradable sustained release nanoparticles (NPs) may circumvent these limitations. We describe here the development, characterization, and bioactivity assessment of novel formulations of poly(D,L-lactic-co-glycolic acid)-poly(ethylene glycol) (PLGA-PEG) NPs loaded with pomegranate extract (PE) or individual polyphenols such as PU or EA. Monodispersed, spherical 150-200 nm average diameter NPs were prepared by the double emulsion-solvent evaporation method. Uptake of Alexa Fluor-488-labeled NPs was evaluated in MCF-7 breast cancer cells over a 24-hour time course. Confocal fluorescent microscopy revealed that PLGA-PEG NPs were efficiently taken up, and the uptake reached the maximum at 24 hours. In addition, we examined the antiproliferative effects of PE-, PU-, and/or EA-loaded NPs in MCF-7 and Hs578T breast cancer cells. We found that PE, PU, and EA nanoprototypes had a 2- to 12-fold enhanced effect on cell growth inhibition compared to their free counterparts, while void NPs did not affect cell growth. PU-NPs were the most potent nanoprototype of pomegranates. Thus, PU may be the polyphenol of choice for further chemoprevention studies with pomegranate nanoprototypes. These data demonstrate that nanotechnology-enabled delivery of pomegranate polyphenols enhances their anticancer effects in breast cancer cells. Thus, pomegranate polyphenols are promising agents for nanochemoprevention of breast cancer.

Aspirin as a Chemopreventive Agent for Cancer: a New Hope?

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Isnatin Miladiyah

2016-01-01

Full Text Available Introduction: inflammation has been shown to play a major role in the pathogenesis of cancer. Inflammatory process activates the immune system through pro-inflammatory mediators and subsequent triggers transformation into malignant cells. Some tumors or cancers has been associated with chronic infections, such as hepatitis B and C viruses (hepatocellular carcinoma, human papilloma virus (cervical cancer, Helicobacter pylori (gastric cancer and lymphoma, and prostatitis (prostate cancer. A considerable study have investigated the benefits of aspirin for the prevention and treatment of cancer or tumors. Objectives: This paper aims to describe the relationship between inflammation and cancer incidence, so that use of aspirin as an anti-inflammatory agent is a rational choice in the treatment and prevention of cancer. Conclusion: Aspirin potential for chemoprevention of various types of cancer. Considering the high risk of side effects of aspirin, aspirin is not intended as a routine therapy to prevent the occurrence of cancer.

Cancer chemoprevention and cancer preventive vaccines--a call to action: leaders of diverse stakeholder groups present strategies for overcoming multiple barriers to meet an urgent need.

Science.gov (United States)

Herberman, Ronald B; Pearce, Homer L; Lippman, Scott M; Pyenson, Bruce S; Alberts, David S

2006-12-15

The emerging field of cancer prevention through chemoprevention agents and cancer vaccines offers significant promise for reducing suffering and death from cancer. However, that promise may not be kept unless major barriers to progress are lowered or eliminated. Among the most significant barriers are the relatively small investment from government and industry in research and development of cancer preventive agents; a predominant emphasis of translational cancer research on therapeutic interventions for metastatic or advanced cancer; complexities of prevention trial design; a relatively uncharted Food and Drug Administration (FDA) approval process for preventive agents; insufficient public and patient understanding of the importance and potential for cancer preventive measures, with consequent unpredictable public and patient willingness to take preventive agents; an uncertain reimbursement from payors; and limitations in patent law, liability protection, and data package exclusivity that undermine the opportunity for recouping investment. Viewed individually or collectively, each of these barriers serves as a substantial deterrent to intellectual and financial investment by all sectors of the cancer community. In an effort to ultimately overcome these barriers, a Cancer Prevention Research Summit was assembled June 12-13, 2006 in Bethesda, Maryland, organized by C-Change with support from the AACR. The Summit brought together some 120 leaders from private, public, and not-for-profit entities, including cancer researchers and clinicians; federal health officials; regulatory agency representatives; pharmaceutical, biotech, and food industry leaders; patent attorneys; economists; public and private provider group executives; and advocates. Participants engaged in a detailed process to more carefully define the major barriers, identify potential solutions, and formulate initial priorities and recommendations for action. At the conclusion of this dialogue among

Evidence supporting the conceptual framework of cancer chemoprevention in canines.

Science.gov (United States)

Kondratyuk, Tamara P; Adrian, Julie Ann Luiz; Wright, Brian; Park, Eun-Jung; van Breemen, Richard B; Morris, Kenneth R; Pezzuto, John M

2016-05-24

As with human beings, dogs suffer from the consequences of cancer. We investigated the potential of a formulation comprised of resveratrol, ellagic acid, genistein, curcumin and quercetin to modulate biomarkers indicative of disease prevention. Dog biscuits were evaluated for palatability and ability to deliver the chemopreventive agents. The extent of endogenous DNA damage in peripheral blood lymphocytes from dogs given the dietary supplement or placebo showed no change. However, H2O2-inducible DNA damage was significantly decreased after consumption of the supplement. The expression of 11 of 84 genes related to oxidative stress was altered. Hematological parameters remained in the reference range. The concept of chemoprevention for the explicit benefit of the canine is compelling since dogs are an important part of our culture. Our results establish a proof-of-principle and provide a framework for improving the health and well-being of "man's best friend".

Molecular Mechanisms Behind the Chemopreventive Effects of Anthocyanidins

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De-Xing Hou

2004-01-01

Full Text Available Anthocyanins are polyphenolic ring-based flavonoids, and are widespread in fruits and vegetables of red-blue color. Epidemiological investigations and animal experiments have indicated that anthocyanins may contribute to cancer chemoprevention. The studies on the mechanism have been done recently at molecular level. This review summarizes current molecular bases for anthocyanidins on several key steps involved in cancer chemoprevention: (i inhibition of anthocyanidins in cell transformation through targeting mitogen-activated protein kinase (MAPK pathway and activator protein 1 (AP-1 factor; (ii suppression of anthocyanidins in inflammation and carcinogenesis through targeting nuclear factor kappa B (NF-κB pathway and cyclooxygenase 2 (COX-2 gene; (iii apoptotic induction of cancer cells by anthocyanidins through reactive oxygen species (ROS / c-Jun NH2-terminal kinase (JNK-mediated caspase activation. These data provide a first molecular view of anthocyanidins contributing to cancer chemoprevention.

The Role of Nutraceuticals in Chemoprevention and Chemotherapy and Their Clinical Outcomes

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Sabita N. Saldanha

2012-01-01

Full Text Available The genesis of cancer is often a slow process and the risk of developing cancer increases with age. Altering a diet that includes consumption of beneficial phytochemicals can influence the balance and availability of dietary chemopreventive agents. In chemopreventive approaches, foods containing chemicals that have anticancer properties can be supplemented in diets to prevent precancerous lesions from occurring. This necessitates further understanding of how phytochemicals can potently maintain healthy cells. Fortunately there is a plethora of plant-based phytochemicals although few of them are well studied in terms of their application as cancer chemopreventive and therapeutic agents. In this analysis we will examine phytochemicals that have strong chemopreventive and therapeutic properties in vitro as well as the design and modification of these bioactive compounds for preclinical and clinical applications. The increasing potential of combinational approaches using more than one bioactive dietary compound in chemoprevention or cancer therapy will also be evaluated. Many novel approaches to cancer prevention are on the horizon, several of which are showing great promise in saving lives in a cost-effective manner.

Black tea: Phytochemicals, cancer chemoprevention, and clinical studies.

Science.gov (United States)

Singh, Brahma N; Rawat, A K S; Bhagat, R M; Singh, B R

2017-05-03

Tea (Camellia sinensis L.) is the most popular, flavored, functional, and therapeutic non-alcoholic drink consumed by two-thirds of the world's population. Black tea leaves are reported to contain thousands of bioactive constituents such as polyphenols, amino acids, volatile compounds, and alkaloids that exhibit a range of promising pharmacological properties. Due to strong antioxidant property, black tea inhibits the development of various cancers by regulating oxidative damage of biomolecules, endogenous antioxidants, and pathways of mutagen and transcription of antioxidant gene pool. Regular drinking of phytochemicals-rich black tea is linked to regulate several molecular targets, including COX-2, 5-LOX, AP-1, JNK, STAT, EGFR, AKT, Bcl2, NF-κB, Bcl-xL, caspases, p53, FOXO1, TNFα, PARP, and MAPK, which may be the basis of how dose of black tea prevents and cures cancer. In vitro and preclinical studies support the anti-cancer activity of black tea; however, its effect in human trails is uncertain, although more clinical experiments are needed at molecular levels to understand its anti-cancer property. This review discusses the current knowledge on phytochemistry, chemopreventive activity, and clinical applications of black tea to reveal its anti-cancer effect.

Glucoraphanin, the bioprecursor of the widely extolled chemopreventive agent sulforaphane found in broccoli, induces Phase-I xenobiotic metabolizing enzymes and increases free radical generation in rat liver

Energy Technology Data Exchange (ETDEWEB)

Perocco, Paolo [Department of Experimental Pathology, Cancerology Section, viale Filopanti 22, I-40126, University of Bologna, Bologna (Italy); Bronzetti, Giorgio [Institute of Biology and Agricultural Biotechnology - CNR Research Area, via Moruzzi, I-56124 Pisa (Italy); Canistro, Donatella; Sapone, Andrea; Affatato, Alessandra; Pozzetti, Laura; Broccoli, Massimiliano [Department of Pharmacology, Molecular Toxicology Unit, via Irnerio 48, I-40126, University of Bologna, Bologna (Italy); Valgimigli, Luca [Department of Organic Chemistry ' A. Mangini' , Viale Risorgimento 4, I-40127, Alma-Mater Studiorum, University of Bologna, Bologna (Italy); Pedulli, Gian Franco [Department of Organic Chemistry ' A. Mangini' , Viale Risorgimento 4, I-40127, Alma-Mater Studiorum, University of Bologna, Bologna (Italy); Iori, Renato [C.R.A - Research Institute for Industrial Crops, via di Corticella 133, I-40129 Bologna (Italy); Barillari, Jessica [Institute of Biology and Agricultural Biotechnology - CNR Research Area, via Moruzzi, I-56124 Pisa (Italy)]|[C.R.A - Research Institute for Industrial Crops, via di Corticella 133, I-40129 Bologna (Italy); Sblendorio, Valeriana [Department of Pharmacology, Molecular Toxicology Unit, via Irnerio 48, I-40126, University of Bologna, Bologna (Italy); Legator, Marvin S. [Department of Preventive Medicine and Community Health, Division of Environmental Toxicology, The University of Texas Medical Branch at Galveston, 700 Harborside Drive, Galveston, TX 77555-1110 (United States); Paolini, Moreno [Department of Pharmacology, Molecular Toxicology Unit, via Irnerio 48, I-40126, University of Bologna, Bologna (Italy); Abdel-Rahman, Sherif Z. [Department of Preventive Medicine and Community Health, Division of Environmental Toxicology, The University of Texas Medical Branch at Galveston, 700 Harborside Drive, Galveston, TX 77555-1110 (United States)]. E-mail: sabdelra@utmb.edu

2006-03-20

Epidemiological and animal studies linking high fruit and vegetable consumption to lower cancer risk have strengthened the belief that long-term administration of isolated naturally occurring dietary constituents could reduce the risk of cancer. In recent years, metabolites derived from phytoalexins, such as glucoraphanin found in broccoli and other cruciferous vegetables (Brassicaceae), have gained much attention as potential cancer chemopreventive agents. The protective effect of these micronutrients is assumed to be due to the inhibition of Phase-I carcinogen-bioactivating enzymes and/or induction of Phase-II detoxifying enzymes, an assumption that still remains uncertain. The protective effect of glucoraphanin is thought to be due to sulforaphane, an isothiocyanate metabolite produced from glucoraphanin by myrosinase. Here we show, in rat liver, that while glucoraphanin slightly induces Phase-II enzymes, it powerfully boosts Phase-I enzymes, including activators of polycyclic aromatic hydrocarbons (PAHs), nitrosamines and olefins. Induction of the cytochrome P450 (CYP) isoforms CYP1A1/2, CYP3A1/2 and CYP2E1 was confirmed by Western immunoblotting. CYP induction was paralleled by an increase in the corresponding mRNA levels. Concomitant with this Phase-I induction, we also found that glucoraphanin generated large amount of various reactive radical species, as determined by electron paramagnetic resonance (EPR) spectrometry coupled to a radical-probe technique. This suggests that long-term uncontrolled administration of glucoraphanin could actually pose a potential health hazard.

Glucoraphanin, the bioprecursor of the widely extolled chemopreventive agent sulforaphane found in broccoli, induces Phase-I xenobiotic metabolizing enzymes and increases free radical generation in rat liver

International Nuclear Information System (INIS)

Perocco, Paolo; Bronzetti, Giorgio; Canistro, Donatella; Valgimigli, Luca; Sapone, Andrea; Affatato, Alessandra; Pedulli, Gian Franco; Pozzetti, Laura; Broccoli, Massimiliano; Iori, Renato; Barillari, Jessica; Sblendorio, Valeriana; Legator, Marvin S.; Paolini, Moreno; Abdel-Rahman, Sherif Z.

2006-01-01

Epidemiological and animal studies linking high fruit and vegetable consumption to lower cancer risk have strengthened the belief that long-term administration of isolated naturally occurring dietary constituents could reduce the risk of cancer. In recent years, metabolites derived from phytoalexins, such as glucoraphanin found in broccoli and other cruciferous vegetables (Brassicaceae), have gained much attention as potential cancer chemopreventive agents. The protective effect of these micronutrients is assumed to be due to the inhibition of Phase-I carcinogen-bioactivating enzymes and/or induction of Phase-II detoxifying enzymes, an assumption that still remains uncertain. The protective effect of glucoraphanin is thought to be due to sulforaphane, an isothiocyanate metabolite produced from glucoraphanin by myrosinase. Here we show, in rat liver, that while glucoraphanin slightly induces Phase-II enzymes, it powerfully boosts Phase-I enzymes, including activators of polycyclic aromatic hydrocarbons (PAHs), nitrosamines and olefins. Induction of the cytochrome P450 (CYP) isoforms CYP1A1/2, CYP3A1/2 and CYP2E1 was confirmed by Western immunoblotting. CYP induction was paralleled by an increase in the corresponding mRNA levels. Concomitant with this Phase-I induction, we also found that glucoraphanin generated large amount of various reactive radical species, as determined by electron paramagnetic resonance (EPR) spectrometry coupled to a radical-probe technique. This suggests that long-term uncontrolled administration of glucoraphanin could actually pose a potential health hazard

Aspirin as a chemoprevention agent for colorectal cancer.

LENUS (Irish Health Repository)

Lee, Chun Seng

2012-11-01

Colorectal cancer (CRC) is one of the leading causes of mortality in the western world. It is widely accepted that neoplasms such as colonic polyps are precursors to CRC formation; with the polyp-adenoma-carcinoma sequences well described in medical literature [1, 2]. It has been shown that Aspirin and other non-steroid anti-inflammatory drugs (NSAID) have a negative effect on polyp and cancer formation. This review aims to describe some of the mechanism behind the chemoprotective properties of aspirin; COX 2 inhibition, regulation of proliferation and apoptosis and effects on the immune system and also the current evidence that supports its use as a chemoprevention agent against CRC. We will also aim to explore the side effects with the use of aspirin and the pitfalls of using aspirin routinely for primary prophylaxis against CRC.

Chronic unpredictable stress deteriorates the chemopreventive efficacy of pomegranate through oxidative stress pathway.

Science.gov (United States)

Hasan, Shirin; Suhail, Nida; Bilal, Nayeem; Ashraf, Ghulam Md; Zaidi, Syed Kashif; AlNohair, Sultan; Banu, Naheed

2016-05-01

Chronic unpredictable stress (CUS) can influence the risk and progression of cancer through increased oxidative stress. Pomegranate is known to protect carcinogenesis through its anti-oxidative properties. This study is carried out to examine whether CUS affects the chemopreventive potential of pomegranate through oxidative stress pathway. Role of CUS on early stages of 7, 12 dimethyl benz(a) anthracene (DMBA) induced carcinogenesis, and its pre-exposure effect on chemopreventive efficacy of pomegranate juice (PJ) was examined in terms of in vivo antioxidant and biochemical parameters in Swiss albino rats. Rats were divided in various groups and were subjected to CUS paradigm, DMBA administration (65 mg/kg body weight, single dose), and PJ treatment. Exposure to stress (alone) and DMBA (alone) led to increased oxidative stress by significantly decreasing the antioxidant enzymes activities and altering the glutathione (GSH), malondialdehyde (MDA), glutamate oxaloacetate transaminase (GOT), and glutamate pyruvate transaminase (GPT) levels. A significant increase in DNA damage demonstrated by comet assay was seen in the liver cells. Stress exposure to DMBA-treated rats further increased the oxidative stress and disturbed the biochemical parameters as compared to DMBA (alone)-treated rats. Chemoprevention with PJ in DMBA (alone)-treated rats restored the altered parameters. However, in the pre-stress DMBA-treated rats, the overall antioxidant potential of PJ was significantly diminished. Our results indicate that chronic stress not only increases the severity of carcinogenesis but also diminishes the anti-oxidative efficacy of PJ. In a broader perspective, special emphasis should be given to stress management and healthy diet during cancer chemoprevention.

Beneficial and adverse effects of chemopreventive agents

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Lee, Byung Mu; Park, Kwang-Kyun

2003-03-01

The beneficial and adverse effects of some chemopreventive agents, such as Vitamins A, C, E, beta-carotene, indole-3-carbinol, capsaicin, garlic, and aloe are reviewed. Two large randomized trials with a lung cancer endpoint, the Alpha-Tocopherol, Beta-Carotene (ATBC) Prevention Study and the Beta-Carotene and Retinol Efficacy Trial (CARET), suggested that antioxidants might be harmful in smokers. However, the results of the Linxian study and of the ATBC or the CARET studies were significantly different in this respect, and therefore, the relationship between antioxidant and carcinogenesis remains open to debate. Indole-3-carbinol has cancer promoting activities in the colon, thyroid, pancreas, and liver, whereas capsaicin alters the metabolism of chemical carcinogens and may promote carcinogenesis at high doses. Organosulfur compounds and selenium from garlic have no or a little enhancing effect on cancer promotion stage. Information upon chemopreventive mechanisms that inhibit carcinogenesis is imperfect, although the causes and natures of certain human cancers are known. Therefore, definitive preventive guidelines should be carefully offered for various types of tumors, which properly consider ethnic variations, and the efficacies and the safety of chemopreventive agents.

Beneficial and adverse effects of chemopreventive agents

International Nuclear Information System (INIS)

Lee, Byung Mu; Park, Kwang-Kyun

2003-01-01

The beneficial and adverse effects of some chemopreventive agents, such as Vitamins A, C, E, beta-carotene, indole-3-carbinol, capsaicin, garlic, and aloe are reviewed. Two large randomized trials with a lung cancer endpoint, the Alpha-Tocopherol, Beta-Carotene (ATBC) Prevention Study and the Beta-Carotene and Retinol Efficacy Trial (CARET), suggested that antioxidants might be harmful in smokers. However, the results of the Linxian study and of the ATBC or the CARET studies were significantly different in this respect, and therefore, the relationship between antioxidant and carcinogenesis remains open to debate. Indole-3-carbinol has cancer promoting activities in the colon, thyroid, pancreas, and liver, whereas capsaicin alters the metabolism of chemical carcinogens and may promote carcinogenesis at high doses. Organosulfur compounds and selenium from garlic have no or a little enhancing effect on cancer promotion stage. Information upon chemopreventive mechanisms that inhibit carcinogenesis is imperfect, although the causes and natures of certain human cancers are known. Therefore, definitive preventive guidelines should be carefully offered for various types of tumors, which properly consider ethnic variations, and the efficacies and the safety of chemopreventive agents

Chemoprevention of skin cancer by the flavonoid fraction of Saraca asoka.

Science.gov (United States)

Cibin, T R; Devi, D Gayathri; Abraham, Annie

2010-05-01

Saraca asoka (Family - Caesalpiniaceae) has been widely used in the Ayurvedic (traditional Indian) system of medicine especially due to its wound healing property. The present study investigated the chemopreventive property of flavonoids from the flowers of Saraca asoka on 7,12 dimethyl benz(a)anthracene (DMBA) induced skin cancer in mice models. A single topical application of DMBA (100 microg/50 microL of acetone) followed after 2 weeks by three times a week treatment with croton oil (1% in acetone), for 20 weeks resulted in tumor induction. The topical application of the flavonoid fraction of S. asoka (FF S. asoka), 30 min prior to the application of croton oil thrice weekly for 20 weeks, caused a significant reduction in the number of tumors per mouse and the percentage of tumor-bearing mice. Also the latency period for the appearance of the first tumor was delayed by S. asoka pretreatment. In the flavonoid fraction (5 mg and 10 mg/kg body weight) treated animals, the levels of biochemical markers - rhodanese, myeloperoxidase, beta-D-glucuronidase, sialic acid, hexokinase and caspase 3 were significantly restored to near normal levels. These findings suggest the chemopreventive activity of flavonoids from S. asoka on two stage skin carcinogenesis. Histological data also support the chemopreventive potential of S. asoka. Copyright (c) 2009 John Wiley & Sons, Ltd.

PPARγ Ligand as a Promising Candidate for Colorectal Cancer Chemoprevention: A Pilot Study

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Hirokazu Takahashi

2010-01-01

Full Text Available Activating synthetic ligands for peroxisome proliferator-activated receptor gamma (PPARγ, such as pioglitazone, are commonly used to treat persons with diabetes mellitus with improvement of insulin resistance. Several reports have clearly demonstrated that PPARγ ligands could inhibit colorectal cancer cell growth and induce apoptosis. Meanwhile, aberrant crypt foci (ACF have come to be established as a biomarker of the risk of CRC in azoxymethane-treated mice and rats. In humans, ACF can be detected using magnifying colonoscopy. Previously, CRC and adenoma were used as a target for chemopreventive agents, but it needs a long time to evaluate, however, ACF can be a surrogate marker of CRC even for a brief period. In this clinical study, we investigated the chemopreventive effect of pioglitazone on the development of human ACF as a surrogate marker of CRC. Twenty-nine patients were divided into two groups, 20 were in the endoscopically normal control group and 9 were in the pioglitazone (15 mg/day group, and ACF and adenoma were examined before and after 1-month treatment. The number of ACF was significantly decreased (5.8±1.1 to 3.3±2.3 after 1 month of pioglitazone treatment, however, there was no significant change in the number of crypts/ACF or in the number and size of adenomas. Pioglitazone may have a clinical application as a cancer-preventive drug. This investigation is just a pilot study, therefore, further clinical studies are needed to show that the PPARγ ligand may be a promising candidate as a chemopreventive agent for colorectal carcinogenesis.

Chemopreventive effects of NSAIDs as inhibitors of cyclooxygenase-2 and inducers of apoptosis in experimental lung carcinogenesis.

Science.gov (United States)

Setia, Shruti; Vaish, Vivek; Sanyal, Sankar Nath

2012-07-01

Roles of cyclooxygenase (COX) enzyme and intrinsic pathway of apoptosis have been explored for the chemopreventive effects of non-steroidal anti-inflammatory drugs (NSAIDs) on 9,10-dimethyl benz(a)anthracene (DMBA)-induced lung cancer in rat model. 16 weeks after the administration of DMBA, morphological analysis revealed the occurrences of tumours and lesions, which were regressed considerably with the co-administration of indomethacin and etoricoxib, the two NSAIDs under investigation. DMBA group was marked by hyperplasia and dysplasia as observed by histological examination, and these features were corrected to a large extent by the two NSAIDs. Elevated levels of COX-2 were seen in the DMBA group, the enzyme responsible for prostaglandin synthesis during inflammation and cancer, whilst the expression of the constitutive isoform, COX-1, was equally expressed in all the groups. Apoptosis was quantified by studying the activities of apaf-1, caspase-9, and 3 by immunofluorescence and western blots. Their activities were found to diminish in the DMBA-treated animals as compared to the other groups. Fluorescent co-staining of the isolated broncho-alveolar lavage cells showed reduced number of apoptotic cells in the DMBA group, indicating decrease in apoptosis after carcinogen administration. The present results thus suggest that the mechanism of cancer chemoprevention of NSAIDs may include the suppression of COX-2 and the induction of apoptosis.

Drugs with potential chemopreventive properties in relation to epithelial ovarian cancer--a nationwide case-control study.

Science.gov (United States)

Baandrup, Louise

2015-07-01

Ovarian cancer has a poor prognosis because the disease in the majority of patients is diagnosed at an advanced stage as a result of nonspecific symptoms and lack of efficient screening methods. Because of the poor prognosis of ovarian cancer and the challenge of early detection of the disease, identification of protective factors is important. It has been suggested that some commonly used drugs may have a protective effect against cancer, including ovarian cancer; however, the literature on chemopreventive measures for ovarian cancer is sparse and the results are inconclusive. Most previous studies have substantial methodological constraints, including limited study size and self-reporting of drug use, which introduces potential recall bias and misclassification. This PhD thesis includes a nationwide case-control study to evaluate associations between use of drugs with potential chemopreventive properties and risk of epithelial ovarian cancer. The study is nested in the entire Danish female population using data from the following nationwide registries: the Danish Cancer Registry, the Danish Civil Registration System, the Danish Prescription Registry, the Danish National Patient Register, and registries in Statistics Denmark on fertility, education, and income. Information from the included registries is linked by use of the unique personal identification number assigned to all Danish citizens. The cases were all women in Denmark with epithelial ovarian cancer diagnosed during 2000-2009 (Paper 1) and 2000-2011 (Papers 2 and 3), identified in the Cancer Registry. Age-matched female population controls were randomly selected from the Civil Registration System by risk-set sampling. We required that cases and controls have no history of cancer (except non-melanoma skin cancer) and that controls not previously have undergone bilateral oophorectomy or salpingo-oophorectomy. The total study population comprised 3741 epithelial ovarian cancer cases and 50,576 controls in

Anti-inflammatory, antiproliferative, and cytoprotective activity of NO chimera nitrates of use in cancer chemoprevention.

Science.gov (United States)

Hagos, Ghenet K; Abdul-Hay, Samer O; Sohn, Johann; Edirisinghe, Praneeth D; Chandrasena, R Esala P; Wang, Zhiqiang; Li, Qian; Thatcher, Gregory R J

2008-11-01

Nonsteroidal anti-inflammatory drugs (NSAIDs) have shown promise in colorectal cancer (CRC), but they are compromised by gastrotoxicity. NO-NSAIDs are hybrid nitrates conjugated to an NSAID designed to exploit the gastroprotective properties of NO bioactivity. The NO chimera ethyl 2-((2,3-bis(nitrooxy)propyl)disulfanyl)benzoate (GT-094), a novel nitrate containing an NSAID and disulfide pharmacophores, is effective in vivo in rat models of CRC and is a lead compound for design of agents of use in CRC. Preferred chemopreventive agents possess 1) antiproliferative and 2) anti-inflammatory actions and 3) the ability to induce cytoprotective phase 2 enzymes. To determine the contribution of each pharmacophore to the biological activity of GT-094, these three biological activities were studied in vitro in compounds that deconstructed the structural elements of the lead GT-094. The anti-inflammatory and antiproliferative actions of GT-094 in vivo were recapitulated in vitro, and GT-094 was seen to induce phase 2 enzymes via the antioxidant responsive element. In the variety of colon, macrophage-like, and liver cell lines studied, the evidence from structure-activity relationships was that the disulfide structural element of GT-094 is the dominant contributor in vitro to the anti-inflammatory activity, antiproliferation, and enzyme induction. The results provide a direction for lead compound refinement. The evidence for a contribution from the NO mimetic activity of nitrates in vitro was equivocal, and combinations of nitrates with acetylsalicylic acid were inactive.

Crocus sativus L. (saffron for cancer chemoprevention: A mini review

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Prasan R. Bhandari

2015-04-01

Full Text Available Cancer is one of the most feared diseases globally and there has been a sustained rise in its incidence in both developing and developed countries. Despite the growing therapeutic options for patients with cancer, their efficacy is time-limited and non-curative. Hence to overcome these drawbacks, an incessant screening for superior and safer drugs has been ongoing for numerous decades, resulting in the detection of anti-cancer properties of several phytochemicals. Chemoprevention using readily available natural substances from vegetables, fruits, herbs and spices is one of the significantly important approaches for cancer prevention in the present era. Among the spices, Crocus sativus L. (saffron; 番紅花 fān hóng huā has generated interest because pharmacological experiments have established numerous beneficial properties including radical scavenging, anti-mutagenic and immuno-modulating effects. The more powerful components of saffron are crocin, crocetin and safranal. Studies in animal models and with cultured human malignant cell lines have demonstrated antitumor and cancer preventive activities of saffron and its main ingredients. This review provides a brief insight into the anticancer properties of saffron and its components.

Oleuropein and Cancer Chemoprevention: The Link is Hot

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Ammad Ahmad Farooqi

2017-04-01

Full Text Available Cancer comprises a collection of related diseases characterized by the existence of altered cellular pathways resulting in an abnormal tendency for uncontrolled growth. A broad spectrum, coordinated, and personalized approach focused on targeting diverse oncogenic pathways with low toxicity and economic natural compounds can provide a real benefit as a chemopreventive and/or treatment of this complex disease. Oleuropein, a bioactive phenolic compound mainly present in olive oil and other natural sources, has been reported to modulate several oncogenic signalling pathways. This review presents and critically discusses the available literature about the anticancer and onco-suppressive activity of oleuropein and the underlying molecular mechanisms implicated in the anticarcinogenic and therapeutic effects. The existence of limitations and the promising perspectives of research on this phenolic compound are also critically analyzed and discussed.

Dietary Glucosinolates Sulforaphane, Phenethyl Isothiocyanate, Indole-3-Carbinol/3,3'-Diindolylmethane: Anti-Oxidative Stress/Inflammation, Nrf2, Epigenetics/Epigenomics and In Vivo Cancer Chemopreventive Efficacy.

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Fuentes, Francisco; Paredes-Gonzalez, Ximena; Kong, Ah-Ng Tony

2015-05-01

Glucosinolates are a group of sulfur-containing glycosides found in many plant species, including cruciferous vegetables such as broccoli, cabbage, brussels sprouts, and cauliflower. Accumulating evidence increasingly supports the beneficial effects of dietary glucosinolates on overall health, including as potential anti-cancer agents, because of their role in the prevention of the initiation of carcinogenesis via the induction of cellular defense detoxifying/antioxidant enzymes and their epigenetic mechanisms, including modification of the CpG methylation of cancer-related genes, histone modification regulation and changes in the expression of miRNAs. In this context, the defense mechanism mediated by Nrf2-antioxidative stress and anti-inflammatory signaling pathways can contribute to cellular protection against oxidative stress and reactive metabolites of carcinogens. In this review, we summarize the cancer chemopreventive role of naturally occurring glucosinolate derivatives as inhibitors of carcinogenesis, with particular emphasis on specific molecular targets and epigenetic alterations in in vitro and in vivo human cancer animal models.

Clinical cancer chemoprevention: From the hepatitis B virus (HBV vaccine to the human papillomavirus (HPV vaccine

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Horng-Jyh Tsai

2015-04-01

Full Text Available Approximately 2 million new cancer cases are attributed to infectious agents each year worldwide. Vaccines for the hepatitis B virus (HBV, a risk factor of hepatocellular cancer, and human papillomavirus (HPV, a risk factor of cervical cancer, are considered major successes in clinical chemoprevention of cancer. In Taiwan, the first evidence of cancer prevention through vaccinations was provided by HBV vaccination data in infants. The Taiwanese HBV vaccination program has since become a model immunization schedule for newborns worldwide. Persistent infection with high-risk HPV is generally accepted as prerequisite for cervical cancer diagnosis; however, cervical cancer is a rare complication of HPV infections. This is due to the fact that such infections tend to be transient. The safety and efficacy of both available HPV quadrivalent vaccine and bivalent vaccine are not in doubt at the present time. Until a human cytomegalovirus (CMV vaccine becomes available, simple hygienic practices, such as hand washing, can prevent CMV infection both before and during pregnancy. Each country should establish her official guidelines regarding which vaccines should be used to treat various conditions, the target population (i.e., universal or limited to a selected population, and the immunization schedules. After a vaccine is recommended, decisions regarding reimbursement by the public health care fund are evaluated. The guidelines become part of the immunization schedule, which is updated annually and published in the official bulletin. In conclusion, both HBV and HPV vaccines are considered major successes in the chemoprevention of cancer.

Chemoprevention of DMH-induced rat colon carcinoma initiation by combination administration of piroxicam and C-phycocyanin.

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Saini, Manpreet Kaur; Vaiphei, Kim; Sanyal, Sankar Nath

2012-02-01

Cancer research illustrated that combinatorial studies can provide significant improvement in safety and effectiveness over the monotherapy regimens. A combination of two drugs may restrain precancerous colon polyps, opening a new possible opportunity for chemoprevention of colon cancer. In this context, chemopreventive efficacy of a combination regimen of C-phycocyanin, a biliprotein present in Spirulina platensis, a cyanobacterium, which is a selective cycloxygenase-2 (COX-2) inhibitor and piroxicam, a traditional non-steroidal anti-inflammatory drug was considered in 1,2 dimethylhyadrazine (DMH)-induced colon carcinogenesis in rats. Western blotting, immunohistochemistry, DNA fragmentation, fluorescent staining, PGE(2) enzyme immunoassay, and carrageenan-induced paw edema test were performed along with morphological and histological analysis. DMH treatment showed a rich presence of preneoplastic lesions such as multiple plaque lesions, aberrant crypt foci, and well-characterized dysplasia. These features were reduced with piroxicam and C-phycocyanin administration. The number of apoptotic cells was featured prominently in all the groups compared with DMH. DMH treatment revealed intact high molecular weight genomic DNA with no signs of laddering/DNA fragmentation while it was noticeable significantly in control and DMH + piroxicam + C-phycocyanin. DMH group showed highest COX-2 expression and PGE(2) level in comparison with other groups. Doses of piroxicam and C-phycocyanin used in the present study were established at an anti-inflammatory range. A combination regimen of piroxicam and C-phycocyanin, rather than individually has the much greater potential for reduction of DMH-induced colon cancer development and COX-2 being the prime possible target in such chemoprevention.

Chemopreventive Effects of Magnesium Chloride Supplementation on Hormone Independent Prostate Cancer Cells

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Elsa Quiroz

2016-01-01

Full Text Available Background: Lifestyle significantly impacts the risk factors associated with prostate cancer, out of which diet appears to be the most influential. An emerging chemopreventive approach, which involves the adequate intake of dietary constituents, has shown great potential in preventing the occurrence or progression of cancer. Magnesium is known to be an essential cofactor for more than 300 enzymatic processes, and is responsible for the regulation of various cellular reactions in the body. A plethora of studies have shown evidence that changes in the intracellular levels of magnesium could contribute to cell proliferation and apoptosis in some normal and malignant cells. The aim of the study was to investigate the effects of magnesium chloride (MgCl2 in DU-145 prostate cancer cells. Methodology: Cultured DU-145 cells were subjected to graded concentrations or doses (50-500 µM of MgCl2 for 48 hours. The cell viability was assessed using MTT and Resazurin reduction assays. NBT assay was also used to assess the treatment-induced intracellular ROS levels. Acridine Orange/Ethidium Bromide (AcrO/EtBr and Rh123/EtBr fluorescent stains were used to assess the cell death type and mitochondrial membrane potential (Δψm respectively. Results: The results revealed a dose-dependent decrease (P < 0.05 in cell viability in treated DU-145 cells after 48 hours. The NBT assay also revealed a dose dependent biphasic response (P < 0.05 in intracellular levels of ROS. There was a drop (P < 0.05 in ROS levels in all groups except at 100 µM, where ROS level was higher than the control. Apoptosis was the primary mode of cell death as observed in the fluorescence analysis. Conclusion: Our finding suggests that MgCl2 may be potentially chemopreventive for prostate cancer. This justifies further studies into its mechanism of action in DU-145 and other prostate cancer cell types.

Chemical carcinogenesis and chemoprevention: Scientific priority ...

African Journals Online (AJOL)

Occupational cancers are now a serious concern in industrializing developing countries where exposure levels to hazardous chemicals considerably exceed regulatory limits established in industrialized countries. The association between increasing use of chemicals and associated disorders and chemoprevention or ...

Colon cancer chemoprevention by a novel NO chimera that shows anti-inflammatory and antiproliferative activity in vitro and in vivo.

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Hagos, Ghenet K; Carroll, Robert E; Kouznetsova, Tatiana; Li, Qian; Toader, Violeta; Fernandez, Patricia A; Swanson, Steven M; Thatcher, Gregory R J

2007-08-01

Chemopreventive agents in colorectal cancer possess either antiproliferative or anti-inflammatory actions. Nonsteroidal anti-inflammatory drugs (NSAID) and cyclooxygenase-2 inhibitors have shown promise, but are compromised by side effects. Nitric oxide donor NSAIDs are organic nitrates conjugated via a labile linker to an NSAID, originally designed for use in pain relief, that have shown efficacy in colorectal cancer chemoprevention. The NO chimera, GT-094, is a novel nitrate containing an NSAID and disulfide pharmacophores, a lead compound for the design of agents specifically for colorectal cancer. GT-094 is the first nitrate reported to reduce aberrant crypt foci (by 45%) when administered after carcinogen in the standard azoxymethane rat model of colorectal cancer. Analysis of proximal and distal colon tissue from 8- and 28-week rat/azoxymethane studies showed that GT-094 treatment reduced colon crypt proliferation by 30% to 69%, reduced inducible NO synthase (iNOS) levels by 33% to 67%, reduced poly(ADP-ribose)polymerase-1 expression and cleavage 2- to 4-fold, and elevated levels of p27 in the distal colon 3-fold. Studies in cancer cell cultures recapitulated actions of GT-094: antiproliferative activity and transient G(2)-M phase cell cycle block were measured in Caco-2 cells; apoptotic activity was examined but not observed; anti-inflammatory activity was seen in the inhibition of up-regulation of iNOS and endogenous NO production in lipopolysaccharide (LPS)-induced RAW 264.7 cells. In summary, antiproliferative, anti-inflammatory, and cytoprotective activity observed in vivo and in vitro support GT-094 as a lead compound for the design of NO chimeras for colorectal cancer chemoprevention.

In Vivo Immunomodulation and Lipid Peroxidation Activities Contributed to Chemoprevention Effects of Fermented Mung Bean against Breast Cancer

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Swee Keong Yeap

2013-01-01

Full Text Available Mung bean has been reported to have antioxidant, cytotoxic, and immunomodulatory effects in vitro. Fermented products are reported to have enhanced immunomodulation and cancer chemopreventive effects. In this study, fermented mung bean treatments in vivo were studied by monitoring tumor development, spleen immunity, serum cytokine (interleukin 2 and interferon gamma levels, and spleen/tumor antioxidant levels after injection with low and high risk 4T1 breast cancer cells. Pretreatment with fermented mung bean was associated with delayed tumor formation in low risk mice. Furthermore, this treatment was connected with higher serum anticancer cytokine levels, spleen T cell populations, splenocyte cytotoxicity, and spleen/tumor antioxidant levels. Histopathological evaluation of fermented mung bean treated tumor revealed lower event of mitotic division. On the other hand, antioxidant and nitric oxide levels that were significantly increased in the untreated mice were inhibited in the fermented mung bean treated groups. These results suggested that fermented mung bean has potential cancer chemoprevention effects through the stimulation of immunity, lipid peroxidation, and anti-inflammation.

Cancer Chemoprevention by Resveratrol: The p53 Tumor Suppressor Protein as a Promising Molecular Target

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Danielly C. Ferraz da Costa

2017-06-01

Full Text Available Increasing epidemiological and experimental evidence has demonstrated an inverse relationship between the consumption of plant foods and the incidence of chronic diseases, including cancer. Microcomponents that are naturally present in such foods, especially polyphenols, are responsible for the benefits to human health. Resveratrol is a diet-derived cancer chemopreventive agent with high therapeutic potential, as demonstrated by different authors. The aim of this review is to collect and present recent evidence from the literature regarding resveratrol and its effects on cancer prevention, molecular signaling (especially regarding the involvement of p53 protein, and therapeutic perspectives with an emphasis on clinical trial results to date.

Pomegranate-mediated chemoprevention of experimental hepatocarcinogenesis involves Nrf2-regulated antioxidant mechanisms

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Bishayee, Anupam; Bhatia, Deepak; Thoppil, Roslin J.; Darvesh, Altaf S.; Nevo, Eviatar; Lansky, Ephraim P.

2011-01-01

Hepatocellular carcinoma (HCC), one of the most prevalent and lethal cancers, has shown an alarming rise in the USA. Without effective therapy for HCC, novel chemopreventive strategies may effectively circumvent the current morbidity and mortality. Oxidative stress predisposes to hepatocarcinogenesis and is the major driving force of HCC. Pomegranate, an ancient fruit, is gaining tremendous attention due to its powerful antioxidant properties. Here, we examined mechanism-based chemopreventive potential of a pomegranate emulsion (PE) against dietary carcinogen diethylnitrosamine (DENA)-induced rat hepatocarcinogenesis that mimics human HCC. PE treatment (1 or 10 g/kg), started 4 weeks prior to the DENA challenge and continued for 18 weeks thereafter, showed striking chemopreventive activity demonstrated by reduced incidence, number, multiplicity, size and volume of hepatic nodules, precursors of HCC. Both doses of PE significantly attenuated the number and area of γ-glutamyl transpeptidase-positive hepatic foci compared with the DENA control. PE also attenuated DENA-induced hepatic lipid peroxidation and protein oxidation. Mechanistic studies revealed that PE elevated gene expression of an array of hepatic antioxidant and carcinogen detoxifying enzymes in DENA-exposed animals. PE elevated protein and messenger RNA expression of the hepatic nuclear factor E2-related factor 2 (Nrf2). Our results provide substantial evidence, for the first time, that pomegranate constituents afford chemoprevention of hepatocarcinogenesis possibly through potent antioxidant activity achieved by upregulation of several housekeeping genes under the control of Nrf2 without toxicity. The outcome of this study strongly supports the development of pomegranate-derived products in the prevention and treatment of human HCC, which remains a devastating disease. PMID:21389260

Chemoprevention of esophageal squamous cell carcinoma

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Stoner, Gary D.; Wang Lishu; Chen Tong

2007-01-01

Esophageal squamous cell carcinoma (SCC) is responsible for approximately one-sixth of all cancer-related mortality worldwide. This malignancy has a multifactorial etiology involving several environmental, dietary and genetic factors. Since esophageal cancer has often metastasized at the time of diagnosis, current treatment modalities offer poor survival and cure rates. Chemoprevention offers a viable alternative that could well be effective against the disease. Clinical investigations have shown that primary chemoprevention of this disease is feasible if potent inhibitory agents are identified. The Fischer 344 (F-344) rat model of esophageal SCC has been used extensively to investigate the biology of the disease, and to identify chemopreventive agents that could be useful in human trials. Multiple compounds that inhibit tumor initiation by esophageal carcinogens have been identified using this model. These include several isothiocyanates, diallyl sulfide and polyphenolic compounds. These compounds influence the metabolic activation of esophageal carcinogens resulting in reduced genetic (DNA) damage. Recently, a few agents have been shown to inhibit the progression of preneoplastic lesions in the rat esophagus into tumors. These agents include inhibitors of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), vascular endothelial growth factor (VEGF) and c-Jun [a component of activator protein-1 (AP-1)]. Using a food-based approach to cancer prevention, we have shown that freeze-dried berry preparations inhibit both the initiation and promotion/progression stages of esophageal SCC in F-344 rats. These observations have led to a clinical trial in China to evaluate the ability of freeze-dried strawberries to influence the progression of esophageal dysplasia to SCC

Intrinsic mitochondrial membrane potential change and associated events mediate apoptosis in chemopreventive effect of diclofenac in colon cancer.

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Kaur, Jasmeet; Sanyal, S N

2010-01-01

The present study explored the role of intrinsic mitochondrial membrane potential (delta psi M) in NSAID-induced apoptosis in the early stages of colon cancer. 1,2-Dimethylhydrazine dihydrochloride (DMH) was used to induce colon cancer and its chemoprevention was studied by diclofenac in a rat model. After 6 weeks of treatment with DMH (early stage), morphological analysis revealed a marked occurrence of preneoplastic features [i.e., mucosal plaque lesions (MPLs) in the colonic tissue]. Coadministration of diclofenac with DMH resulted in a significant reduction of these lesions, thereby proving the chemopreventive efficacy of diclofenac at the chosen anti-inflammatory dose. DMH treatment also led to a significant increase in delta psi M in the isolated colonocytes as assessed by JC-1 fluorescent staining, measured both by fluorescence microscopy and spectrofluorometerically. Further, there was seen a reduction in the number of cells showing low delta psi M, and hence monomer intensity of JC-1 by DMH treatment. To study the mechanism of these alterations in delta psi M in the present work, we studied the protein expression of important proapoptotic proteins, cytochrome c and Bax, by Western blot analysis and immunohistochemistry. DMH treatment reduced the mitochondrial translocation of Bax whereas cytochrome c was found to be located prominently in the mitochondria. Protein expression of antiapoptotic Bcl-2 was also studied in the colonic mucosa, which was expectedly found to be overexpressed after DMH treatment. Diclofenac treatment ameliorated the elevated delta psi M and its associated events to exert its chemopreventive action against early stages of colon cancer.

Evaluation of chemopreventive potential of Strobilanthes crispus against colon cancer formation in vitro and in vivo.

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Al-Henhena, Nawal; Khalifa, Shaden A M; Ying, Rozaida Poh Yuen; Ismail, Salmah; Hamadi, Riad; Shawter, Abdrabu N; Idris, Azila Mohd; Azizan, Ainnul; Al-Wajeeh, Nahla Saeed; Abdulla, Mahmood Ameen; El-Seedi, Hesham R

2015-11-25

With cancer being one of the major causes of death around the world, studies are ongoing to find new chemotherapeutic leads. There are common mechanisms for colorectal cancer (CRC) formation. Several are connected with oxidative stress-induced cell apoptosis and others are related to imbalanced homeostasis or intake of drugs/toxins. Plants that have been used for decades in folk and traditional medicine have been accepted as one of the commonest sources of discovered natural agents of cancer chemotherapy and chemoprevention. The aim was to study the antioxidant and chemopreventive effects of Strobilanthes crispus on colorectal cancer formation. Five groups of rats were injected subcutaneously with AOM, 15 mg/kg body weight, each once weekly for 2 weeks. The cancer group was continued on 10 % Tween-20 feeding for 8 weeks. The standard drug group was continued on 35 mg/kg 5-fluorouracil intraperitoneal injection twice a week for 8 weeks, and the experimental groups were continued on 250 and 500 mg/kg S. crispus extract oral feeding for 8 weeks, respectively. The normal group was injected subcutaneously with normal saline once a week for 2 weeks, followed by oral administration of 10 % Tween-20 for 8 weeks. All the rats were sacrificed after 10 weeks. The colons were evaluated grossly and histopathologically for aberrant crypt foci (ACF). Gene expression was performed for Bax, Bcl2, Defa24, Slc24a3, and APC genes by real-time PCR. S. crispus and its fractions were evaluated for their chemopreventive effects against human colorectal adenocarcinoma cell line HT29 and cytotoxicity for normal human colon epithelial cell line CCD 841, and the active fraction was assessed for its components. We observed significant decrease in total colonic ACF formation, malonaldehyde (MDA) and lactate dehydrogenase (LDH), increase in superoxide dismutase (SOD), up-regulation of APC, Bax and Slc24a3, and down-regulation of Defa24 and Bcl-2 in rats treated with Strobilanthes

Chemopreventive effect of Cynodon dactylon (L.) Pers. extract against DMH-induced colon carcinogenesis in experimental animals.

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Albert-Baskar, Arul; Ignacimuthu, Savarimuthu

2010-07-01

The present study was aimed at evaluating the chemopreventive property of Cynodon dactylon. The antioxidant, antiproliferative and apoptotic potentials of the plant were investigated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, nitric oxide radical scavenging activity (NO(-)) and MTT assay on four cancer cell lines (COLO 320 DM, MCH-7, AGS, A549) and a normal cell line (VERO). In vivo chemopreventive property of the plant extract was studied in DMH-induced colon carcinogenesis. The methanolic extract of C. dactylon was found to be antiproliferative and antioxidative at lower concentrations and induced apoptotic cell death in COLO 320 DM cells. Treatment with methanolic extract of C. dactylon increased the levels of antioxidant enzymes and reduced the number of dysplastic crypts in DMH-induced colon of albino rats. The present investigation revealed the anticancer potential of methanolic extract of C. dactylon in COLO 320 DM cells and experimentally induced colon carcinogenesis in rats.

The 4Ps of Breast Cancer Chemoprevention: Putting Proven Principles into Practice.

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Jordan, V Craig

2017-04-01

The pioneering Royal Marsden Tamoxifen Prevention Trial recruited 2,471 eligible high-risk women to be randomized to either placebo or tamoxifen (20 mg daily) for 8 years. Breast cancer incidence was evaluated at a median of 18.4 years from the start of the study. There was a 32% reduction in estrogen/progesterone receptor (ER/PR)-positive breast cancers after tamoxifen treatment finished. Translational research, to study "the good, the bad, and the ugly of tamoxifen" in the 1980s, subsequently ensured women's safety from possible increases in osteoperosis, coronary heart disease, and endometrial cancer. Other tamoxifen chemoprevention trials followed. The result of laboratory research was the unanticipated discovery of raloxifene to prevent osteoporosis and breast cancer at the same time. A new group of medicines, now known as selective ER modulators, was established. Indeed, the ability to prevent or delay multiple diseases with a single cheap medicine has the potential to alleviate pressure on health care systems that are overwhelmed. It is a priority to educate physicians appropriately to apply recommended proven medicines as preventives. Cancer Prev Res; 10(4); 219-22. ©2017 AACR See related article by Detre, et al., Cancer Prev Res 2017;10(3):171-6 . ©2017 American Association for Cancer Research.

A Review of the Potential of Phytochemicals from Prunus africana (Hook f. Kalkman Stem Bark for Chemoprevention and Chemotherapy of Prostate Cancer

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Richard Komakech

2017-01-01

Full Text Available Prostate cancer remains one of the major causes of death worldwide. In view of the limited treatment options for patients with prostate cancer, preventive and treatment approaches based on natural compounds can play an integral role in tackling this disease. Recent evidence supports the beneficial effects of plant-derived phytochemicals as chemopreventive and chemotherapeutic agents for various cancers, including prostate cancer. Prunus africana has been used for generations in African traditional medicine to treat prostate cancer. This review examined the potential roles of the phytochemicals from P. africana, an endangered, sub-Saharan Africa plant in the chemoprevention and chemotherapy of prostate cancer. In vitro and in vivo studies have provided strong pharmacological evidence for antiprostate cancer activities of P. africana-derived phytochemicals. Through synergistic interactions between different effective phytochemicals, P. africana extracts have been shown to exhibit very strong antiandrogenic and antiangiogenic activities and have the ability to kill tumor cells via apoptotic pathways, prevent the proliferation of prostate cancer cells, and alter the signaling pathways required for the maintenance of prostate cancer cells. However, further preclinical and clinical studies ought to be done to advance and eventually use these promising phytochemicals for the prevention and chemotherapy of human prostate cancer.

A review of the dietary flavonoid, kaempferol on human health and cancer chemoprevention

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Chen, Allen Y.; Chen, Yi Charlie

2013-01-01

Kaempferol is a polyphenol antioxidant found in fruits and vegetables. Many studies have described the beneficial effects of dietary kaempferol in reducing the risk of chronic diseases, especially cancer. Epidemiological studies have shown an inverse relationship between kaempferol intake and cancer. Kaempferol may help by augmenting the body’s antioxidant defense against free radicals, which promote the development of cancer. At the molecular level, kaempferol has been reported to modulate a number of key elements in cellular signal transduction pathways linked to apoptosis, angiogenesis, inflammation, and metastasis. Significantly, kaempferol inhibits cancer cell growth and angiognesis and induces cancer cell apoptosis, but on the other hand, kaempferol appears to preserve normal cell viability, in some cases exerting a protective effect. The aim of this review is to synthesize information concerning the extraction of kaempferol, as well as to provide insights into the molecular basis of its potential chemo-preventative activities, with an emphasis on its ability to control intracellular signaling cascades that regulate the aforementioned processes. Chemoprevention using nanotechnology to improve the bioavailability of kaempferol is also discussed. PMID:23497863

Combination Chemoprevention with Grape Antioxidants

OpenAIRE

Singh, Chandra K.; Siddiqui, Imtiaz A.; El-Abd, Sabah; Mukhtar, Hasan; Ahmad, Nihal

2016-01-01

Antioxidant ingredients present in grape have been extensively investigated for their cancer chemopreventive effects. However, much of the work has been done on individual ingredients, especially focusing on resveratrol and quercetin. Phytochemically, whole grape represents a combination of numerous phytonutrients. Limited research has been done on the possible synergistic/additive/antagonistic interactions among the grape constituents. Among these phytochemical constituents of grapes, resver...

Dietary factors and cancer chemoprevention: An overview of obesity-related malignancies

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Murthy N

2009-01-01

Full Text Available Obesity is a growing health problem in developed nations and in countries that are in the process of westernization like India. Obesity is linked with several health disorders such as hypertension and cardiovascular diseases, Type 2 diabetes, dyslipidemia and certain cancers. Currently, obesity-related malignancies, e.g., cancers of the breast, prostate and colon are the leading cancers in the industrialized societies. An increased amount of fat or adipose tissue in an overweight or obese person probably influences the development of cancer by releasing several hormone-like factors or adipokines. The majority of adipokines are pro-inflammatory, which promote pathological conditions like insulin resistance and cancer. On the other hand, many recent studies have shown that adiponectin, an anti-inflammatory adipokine, has anti-cancer and insulin-sensitizing effects. Adiponectin exerts its physiological functions chiefly by activation of AMP kinase via adiponectin receptors. Interestingly, several fruits and vegetables may contain adiponectin-like molecules or may increase the biosynthesis of adiponectin in our body. Studies on adiponectin analogues or adiponectin receptor agonists are a promising area of cancer chemoprevention research. In general, fruits and vegetables contain various dietary substances such as vitamins, minerals (like calcium and selenium, fiber and phytochemicals or phenolic compounds (like flavonoids and vanilloids, which may act as anti-cancer agents. Similarly, several dietary constituents including phytochemicals may have anti-obesity effects. Consumption of such dietary compounds along with caloric restriction and physical activity may be helpful in preventing obesity-related cancers. For this review article, we searched PubMed primarily to get the relevant literature.

Resveratrol: Chemoprevention with red wine

OpenAIRE

Arısan, Elif Damla; Palavan-Ünsal, Narçin

2007-01-01

According to epidemiological studies, western diet has disadvantages because of cancer prevalence more than Mediterranean or Asia people who consume more vegetables and fruits. Resveratrol (trans-3,4,5-trihydroxystilbene) which is highly found in grapes, berries has received attention for its potential chemopreventive and antitumor effects in experimental systems. Because of high resveratrol content, researchers noted that red wine has multidimensional benefits for ...

The chemopreventive properties and therapeutic modulation of green tea polyphenols in oral squamous cell carcinoma.

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Lee, Ui-Lyong; Choi, Sung-Weon

2011-01-01

Chemoprevention is a relatively novel and promising approach for controlling cancer that uses specific natural products or synthetic agents to suppress, reverse, or prevent premalignancy before transformation into invasive cancer. Oral cavity squamous cell carcinoma (OCSCC) represents a large, worldwide health burden with approximately 274,000 cases diagnosed annually worldwide. Smoking and alcohol consumption are major inducers of OCSCC. Recently, the human papilloma virus was also shown to potentially be an etiologic factor. Due to its easily identifiable risk factors and the presence of premalignant regions, oral cancer makes a good candidate for chemoprevention. Green tea is the most widely consumed beverage in the world, and it has received considerable attention because of its abundant, scientifically proven, beneficial effects on human health. In this review, we discuss the role of green tea in oral cancer chemoprevention with regard to the multiple molecular mechanisms proposed in various in vitro, in vivo, and clinical trials.

Antimutagenic constituents of adlay (Coix lachryma-jobi L. var. ma-yuen Stapf) with potential cancer chemopreventive activity.

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Chen, Huang-Hui; Chiang, Wenchang; Chang, Jang-Yang; Chien, Ya-Lin; Lee, Ching-Kuo; Liu, Ko-Jiunn; Cheng, Yen-Ting; Chen, Ting-Fang; Kuo, Yueh-Hsiung; Kuo, Ching-Chuan

2011-06-22

Adlay has long been used in traditional Chinese medicine and as a nourishing food. The acetone extract of adlay hull had previously been demonstrated to possess potent antimutagenic activity. The aims of this study were to identify the antimutagenic constituents from adlay hull by using Ames antimutagenic activity-guide isolation procedures and to investigate their chemopreventive efficacies in cultured cells. The results demonstrated that six compounds showing great antimutagenic activity were identified by spectroscopic methods and by comparison with authentic samples to be p-hydroxybenzaldehyde, vanillin, syringaldehyde, trans-coniferylaldehyde, sinapaldehyde, and coixol. Two of them, trans-coniferylaldehyde and sinapaldehyde, exhibit relatively potent scavenging of DPPH radicals, inhibit TPA stimulated superoxide anion generation in neutrophil-like leukocytes, and induce Nrf2/ARE-driven luciferase activity in HSC-3 cells. Moreover, trans-coniferylaldehyde possesses cytoprotective efficacy against tert-butyl hydroperoxide-induced DNA double-strand breaks in cultured cells, and the chemopreventive potency induced by trans-coniferylaldehyde may be through the activation of kinase signals, including p38, ERK1/2, JNK, MEK1/2, and MSK1/2. In summary, we first identified six antimutagenic constituents from adlay hull. Among them, trans-coniferylaldehyde would be a highly promising agent for cancer chemoprevention and merits further investigation.

Targeting arachidonic acid pathway by natural products for cancer prevention and therapy.

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Yarla, Nagendra Sastry; Bishayee, Anupam; Sethi, Gautam; Reddanna, Pallu; Kalle, Arunasree M; Dhananjaya, Bhadrapura Lakkappa; Dowluru, Kaladhar S V G K; Chintala, Ramakrishna; Duddukuri, Govinda Rao

2016-10-01

Arachidonic acid (AA) pathway, a metabolic process, plays a key role in carcinogenesis. Hence, AA pathway metabolic enzymes phospholipase A 2 s (PLA 2 s), cyclooxygenases (COXs) and lipoxygenases (LOXs) and their metabolic products, such as prostaglandins and leukotrienes, have been considered novel preventive and therapeutic targets in cancer. Bioactive natural products are a good source for development of novel cancer preventive and therapeutic drugs, which have been widely used in clinical practice due to their safety profiles. AA pathway inhibitory natural products have been developed as chemopreventive and therapeutic agents against several cancers. Curcumin, resveratrol, apigenin, anthocyans, berberine, ellagic acid, eugenol, fisetin, ursolic acid, [6]-gingerol, guggulsteone, lycopene and genistein are well known cancer chemopreventive agents which act by targeting multiple pathways, including COX-2. Nordihydroguaiaretic acid and baicalein can be chemopreventive molecules against various cancers by inhibiting LOXs. Several PLA 2 s inhibitory natural products have been identified with chemopreventive and therapeutic potentials against various cancers. In this review, we critically discuss the possible utility of natural products as preventive and therapeutic agents against various oncologic diseases, including prostate, pancreatic, lung, skin, gastric, oral, blood, head and neck, colorectal, liver, cervical and breast cancers, by targeting AA pathway. Further, the current status of clinical studies evaluating AA pathway inhibitory natural products in cancer is reviewed. In addition, various emerging issues, including bioavailability, toxicity and explorability of combination therapy, for the development of AA pathway inhibitory natural products as chemopreventive and therapeutic agents against human malignancy are also discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Inhibition of Pro-inflammatory and Anti-apoptotic Biomarkers during Experimental Oral Cancer Chemoprevention by Dietary Black Raspberries

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Steve Oghumu

2017-10-01

Full Text Available Oral cancer continues to be a significant public health problem worldwide. Recently conducted clinical trials demonstrate the ability of black raspberries (BRBs to modulate biomarkers of molecular efficacy that supports a chemopreventive strategy against oral cancer. However, it is essential that a preclinical animal model of black raspberry (BRB chemoprevention which recapitulates human oral carcinogenesis be developed, so that we can validate biomarkers and evaluate potential mechanisms of action. We therefore established the ability of BRBs to inhibit oral lesion formation in a carcinogen-induced rat oral cancer model and examined potential mechanisms. F344 rats were administered 4-nitroquinoline 1-oxide (4NQO (20 µg/ml in drinking water for 14 weeks followed by regular drinking water for 6 weeks. At week 14, rats were fed a diet containing either 5 or 10% BRB, or 0.4% ellagic acid (EA, a BRB phytochemical. Dietary administration of 5 and 10% BRB reduced oral lesion incidence and multiplicity by 39.3 and 28.6%, respectively. Histopathological analyses demonstrate the ability of BRBs and, to a lesser extent EA, to inhibit the progression of oral cancer. Oral lesion inhibition by BRBs was associated with a reduction in the mRNA expression of pro-inflammatory biomarkers Cxcl1, Mif, and Nfe2l2 as well as the anti-apoptotic and cell cycle associated markers Birc5, Aurka, Ccna1, and Ccna2. Cellular proliferation (Ki-67 staining in tongue lesions was inhibited by BRBs and EA. Our study demonstrates that, in the rat 4NQO oral cancer model, dietary administration of BRBs inhibits oral carcinogenesis via inhibition of pro-inflammatory and anti-apoptotic pathways.

Chemoprevention utility of silibinin and Cdk4 pathway inhibition in Apc−/+ mice

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Karim, Baktiar O; Rhee, Ki-Jong; Liu, Guosheng; Zheng, Dongfeng; Huso, David L

2013-01-01

Colorectal cancer (CRC) is the second leading cause of death from cancer in the United States. Colorectal cancers have a prolonged latency following initiation that may span decades providing ample time for implementing a chemoprevention strategy that could block or reverse the progression to CRC. Cdk4 pathway alterations have been linked to a number of cancers including CRC. In these experiments we focused on the Cdk4 pathway and its role in intestinal tumorigenesis as a possible target in chemoprevention strategies. We evaluated the effect of Cdk4 blockade on the prevention of intestinal tumor formation by crossing Cdk4 −/− mice to Apc −/+ mice. In addition, we tested the effect of the dietary compound silibinin on the Cdk4 pathway in Apc −/+ mice and HT-29 colon cancer cells in culture. Cdk4 −/− mice backcrossed to Apc −/+ mice reduced intestinal adenoma formation compared to Apc −/+ controls. Silibinin effectively targeted the Cdk4 pathway causing hypophosphorylation of the retinoblastoma protein, inhibited cell growth, and induced apoptosis. As a result silibinin blocked the development of intestinal adenomas by 52% in this genetic model (Apc −/+ mice) of early events in colorectal cancer formation. No toxic abnormalities were detected in mice which received silibinin. Modification of the Cdk4 pathway using a natural plant-derived compound such as silibinin may be a useful chemopreventive strategy for colorectal carcinomas

Chemoprevention by WR-2721

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Grdina, D.J. [Argonne National Lab., IL (United States)]|[Chicago Univ., IL (United States). Dept. of Radiation and Cellular Oncology; Carnes, B.A. [Argonne National Lab., IL (United States)

1993-05-01

WR-2721 [S-2-(3-aminopropylamino)ethylphosphorothioic acid] is an effective chemopreventive agent. C57BL {times} BALB/c F{sub 1} female mice, were exposed to a single whole-body dose of 206 cGy from a {sup 60}Co photon source. Those groups treated with VATR-2721 (400 mg/kg) were administered the agent i.p. 30 min prior to irradiation. Over 90% of deaths were determined to be due to tumor involvement. WR-2721 afforded significant protection against life shortening due to radiation-induced tumors of connective tissue and epithelial tissue origins. Subsequent survival time in WR-2721-treated and irradiated animals as compared to matched irradiated-only controls was extended up to 59 days. A single exposure of animals to VVR-2721 did not affect the cumulative survival curves for unirradiated mice. WR-2721 possesses chemopreventive properties which can be clinically exploited to reduce the risk to therapy-induced secondary cancers in patients who otherwise would have an excellent prognosis for cure and long-term survival.

Chemoprevention by WR-2721

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Grdina, D.J. (Argonne National Lab., IL (United States) Chicago Univ., IL (United States). Dept. of Radiation and Cellular Oncology); Carnes, B.A. (Argonne National Lab., IL (United States))

1993-01-01

WR-2721 [S-2-(3-aminopropylamino)ethylphosphorothioic acid] is an effective chemopreventive agent. C57BL [times] BALB/c F[sub 1] female mice, were exposed to a single whole-body dose of 206 cGy from a [sup 60]Co photon source. Those groups treated with VATR-2721 (400 mg/kg) were administered the agent i.p. 30 min prior to irradiation. Over 90% of deaths were determined to be due to tumor involvement. WR-2721 afforded significant protection against life shortening due to radiation-induced tumors of connective tissue and epithelial tissue origins. Subsequent survival time in WR-2721-treated and irradiated animals as compared to matched irradiated-only controls was extended up to 59 days. A single exposure of animals to VVR-2721 did not affect the cumulative survival curves for unirradiated mice. WR-2721 possesses chemopreventive properties which can be clinically exploited to reduce the risk to therapy-induced secondary cancers in patients who otherwise would have an excellent prognosis for cure and long-term survival.

Cancer Chemoprevention Effects of Ginger and its Active Constituents: Potential for New Drug Discovery.

Science.gov (United States)

Wang, Chong-Zhi; Qi, Lian-Wen; Yuan, Chun-Su

2015-01-01

Ginger is a commonly used spice and herbal medicine worldwide. Besides its extensive use as a condiment, ginger has been used in traditional Chinese medicine for the management of various medical conditions. In recent years, ginger has received wide attention due to its observed antiemetic and anticancer activities. This paper reviews the potential role of ginger and its active constituents in cancer chemoprevention. The phytochemistry, bioactivity, and molecular targets of ginger constituents, especially 6-shogaol, are discussed. The content of 6-shogaol is very low in fresh ginger, but significantly higher after steaming. With reported anti-cancer activities, 6-shogaol can be served as a lead compound for new drug discovery. The lead compound derivative synthesis, bioactivity evaluation, and computational docking provide a promising opportunity to identify novel anticancer compounds originating from ginger.

Evaluation of sestamibi scanning as a predictor of risk of development of breast cancer and as a non-invasive biomarker for breast cancer chemoprevention trials

International Nuclear Information System (INIS)

Kimler, B.F.; Preston, D.; McMillin, C.H.; Dusing, R.; Zalles, C.M.; Fabian, C.J.

2003-01-01

Sestamibi scintimammography is becoming increasingly accepted as an adjunct to conventional breast imaging by mammography and ultrasound. We sought to determine whether it might serve to detect/quantify pre-cancerous breast lesions, specifically hyperplasia with atypia which, when detected by random periareolar fine needle aspiration (FNA), is known to be associated with increased risk for subsequent development of breast cancer. If a parameter derived from sestamibi scanning could be shown to correlate with and predict for atypia, then this could serve 1) to refine estimates of risk of development of breast cancer; and 2) as a surrogate endpoint biomarker in clinical breast cancer chemoprevention trials. To this end, we performed sestamibi scanning on both breasts of 65 women at high risk for development of breast cancer who also underwent FNA. Seventeen women (26%) exhibited non-proliferative cytology; 30 (46%) had hyperplasia; and 18 (28%) had hyperplasia with atypia in the FNA specimen. Since the fine needle aspiration specimens from both breasts are pooled to provide a single result, we likewise pooled the sestamibi results from both breasts so as to consider the most abnormal finding. Twenty-five women (39%) were characterized as having an abnormal sestamibi scan with heterogenous, focal, intense uptake. There was no correlation between an abnormal scan and cytologic evidence of hyperplasia with atypia. Neither was there a correlation between any of a variety of quantitative measures of the sestamibi scans and the cytological classification. At this time, there is no indication for the use of sestamibi scanning for the prediction of risk of subsequent development of breast cancer, or as a surrogate endpoint biomarker in clinical breast cancer chemoprevention trials

Trianthema portulacastrum Linn. exerts chemoprevention of 7,12-dimethylbenz(a)anthracene-induced mammary tumorigenesis in rats

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Bishayee, Anupam, E-mail: abishayee@auhs.edu [Department of Pharmaceutical Sciences, School of Pharmacy, American University of Health Sciences, Signal Hill, CA 90755 (United States); Mandal, Animesh [Cancer Therapeutics and Chemoprevention Group, Department of Pharmaceutical Sciences, College of Pharmacy, Northeast Ohio Medical University, Rootstown, OH 44272 (United States)

2014-10-15

Highlights: • Dietary administration of an ethanolic extract of aerial parts of T. portulacastrum (TPE) exhibits a striking chemopreventive effect in an experimentally induced classical animal model of breast cancer. • The mammary tumor-inhibitory effect of TPE could be achieved, at least in part, though intervention of key hallmark capabilities of tumor cells, such as abnormal cell proliferation and evasion of apoptosis. • TPE is capable of diminishing activated canonical Wnt/β-catenin signaling to exhibit antiproliferative, proapoptotic and oncostatic effects during this early-stage mammary carcinoma. • These results coupled with a safety profile of T. portulacastrum may encourage further studies to understand the full potential of this dietary plant for chemoprevention of breast cancer. - Abstract: Due to limited treatment options for advanced-stage metastatic breast cancer, a high priority should be given to develop non-toxic chemopreventive drugs. The value of various natural and dietary agents to reduce the risk of developing breast cancer is well established. Trianthema portulacastrum Linn. (Aizoaceae), a dietary and medicinal plant, has been found to exert antihepatotoxic and antihepatocarcinogenic properties in rodents. This study was initiated to investigate mechanism-based chemopreventive potential of an ethanolic extract of T. portulacastrum (TPE) against 7,12-dimethylbenz(a)anthracene (DMBA)-initiated rat mammary gland carcinogenesis, an experimental tumor model that closely resembles human breast cancer. Rats had access to a basal diet supplemented with TPE to yield three dietary doses of the extract, i.e., 50, 100 and 200 mg/kg body weight. Following two weeks of TPE treatment, mammary tumorigenesis was initiated by oral administration of DMBA (50 mg/kg body weight). At the end of the study (16 weeks after DMBA exposure), TPE exhibited a striking reduction of DMBA-induced mammary tumor incidence, total tumor burden and average tumor weight

Chemopreventive Potential of Flavonoids in Oral Squamous Cell Carcinoma in Human Studies

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Elena Maria Varoni

2013-07-01

Full Text Available Evidence available from nutritional epidemiology has indicated an inverse association between regular consumption of fruits and vegetables and the risk of developing certain types of cancer. In turn, preclinical studies have attributed the health-promoting effects of plant foods to some groups of phytochemicals, by virtue of their many biological activities. In this survey, we briefly examine the chemopreventive potential of flavonoids and flavonoid-rich foods in human oral carcinogenesis. Despite the paucity of data from clinical trials and epidemiological studies, in comparison to in vitro/in vivo investigations, a high level of evidence has been reported for epigallocatechin gallate (EGCG and anthocyanins. These flavonoids, abundant in green tea and black raspberries, respectively, represent promising chemopreventive agents in human oral cancer.

Increased chemopreventive effect by combining arctigenin, green tea polyphenol and curcumin in prostate and breast cancer cells

Science.gov (United States)

Wang, Piwen; Wang, Bin; Chung, Seyung; Wu, Yanyuan; Henning, Susanne M.; Vadgama, Jaydutt V.

2014-01-01

The low bioavailability of most flavonoids limits their application as anti-carcinogenic agents in humans. A novel approach of treatment with a mixture of bioactive compounds that share molecular anti-carcinogenic targets may enhance the effect on these targets at low concentrations of individual compound, thereby overcoming the limitations of reduced bioavailability. We therefore investigated whether a combination of three natural products arctigenin (Arc), a novel anti-inflammatory lignan from the seeds of Arctium lappa, green tea polyphenol (−)-epigallocatechin gallate (EGCG) and curcumin (Cur) increases the chemopreventive potency of individual compounds. LNCaP prostate cancer and MCF-7 breast cancer cells were treated with 2–4 mg/L (about 5–10μM) Cur, 1μM Arc and 40μM EGCG alone or in combination for 48h. In both cell lines treatment with the mixture of Cur, Arc and EGCG synergistically increased the antiproliferative effect. In LNCaP cells both Arc and EGCG increased the pro-apoptotic effect of Cur. Whereas in MCF-7 cells Arc increased the cell apoptosis of Cur while EGCG enhanced cell cycle arrest of Cur at G0/G1 phase. The strongest effects on cell cycle arrest and apoptosis were achieved by combining all three compounds in both cell lines. The combination treatment significantly increased the ratio of Bax to Bcl-2 proteins, decreased the activation of NFκB, PI3K/Akt and Stat3 pathways and cell migration compared to individual treatment. These results warrant in vivo studies to confirm the efficacy of this novel regimen by combining Arc and EGCG with Cur to enhance chemoprevention in both prostate and breast cancer. PMID:25243063

The beta-carotene and retinol efficacy trial (CARET) for chemoprevention of lung cancer in high risk populations: smokers and asbestos-exposed workers.

Science.gov (United States)

Omenn, G S; Goodman, G; Thornquist, M; Grizzle, J; Rosenstock, L; Barnhart, S; Balmes, J; Cherniack, M G; Cullen, M R; Glass, A

1994-04-01

CARET is a multicenter, two-armed, double-masked randomized chemoprevention trial in Seattle, Portland, San Francisco, Baltimore, Connecticut, and Irvine, to test whether oral administration of beta-carotene (30 mg/day) plus retinyl palmitate (25,000 IU/day) can decrease the incidence of lung cancer in high risk populations, namely, heavy smokers and asbestos-exposed workers. The intervention combines the antioxidant action of beta-carotene and the tumor suppressor mechanism of vitamin A. As of April 30, 1993, CARET had randomized 1,845 participants in the 1985-1988 pilot phase plus 13,260 "efficacy" participants since 1989; of these, 4,000 are asbestos-exposed males and 11,105 are smokers and former smokers (44% female). Accrual is complete everywhere except Irvine, which was the last center added (1991), and the safety profile of the regimen to date has been excellent. With 14,420 smokers, 4,010 asbestos-exposed participants, and 114,100 person-years through February 1998, we expect CARET to be capable of detecting a 23% reduction in lung cancer incidence in the two populations combined and 27, 49, 32, and 35% reductions in the smokers, female smokers, male smokers, and asbestos-exposed subgroups, respectively. CARET is highly complementary to the alpha-tocopherol-beta-carotene study in Finland and the Harvard Physicians Health Study (beta-carotene alone) in the National Cancer Institute portfolio of major cancer chemoprevention trials.

The REDUCE metagram: a comprehensive prediction tool for determining the utility of dutasteride chemoprevention in men at risk for prostate cancer

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Carvell eNguyen

2012-10-01

Full Text Available Introduction: 5-alpha reductase inhibitors can reduce the risk of prostate cancer but can be associated with significant side effects. A library of nomograms which predict the risk of clinical endpoints relevant to dutasteride treatment may help determine if chemoprevention is suited to the individual patient. Methods: Data from the REDUCE trial was used to identify predictive factors for nine endpoints relevant to dutasteride treatment. Using the treatment and placebo groups from the biopsy cohort, Cox proportional hazards and competing risks regression models were used to build 18 nomograms, whose predictive ability was measured by concordance index and calibration plots. Results: A total of 18 nomograms assessing the risks of cancer, high-grade cancer, high grade prostatic intraepithelial neoplasia (HGPIN, atypical small acinar proliferation (ASAP, erectile dysfunction (ED, acute urinary retention (AUR, gynecomastia, urinary tract infection (UTI and BPH-related surgery either on or off dutasteride were created. The nomograms for cancer, high grade cancer, ED, AUR, and BPH-related surgery demonstrated good discrimination and calibration while those for gynecomastia, UTI, HGPIN, and ASAP predicted no better than random chance. Conclusions: To aid patients in determining whether the benefits of dutasteride use outweigh the risks, we have developed a comprehensive metagram that can generate individualized risks of 9 outcomes relevant to men considering chemoprevention. Better models based on more predictive markers are needed for some of the endpoints but the current metagram demonstrates potential as a tool for patient counseling and decision making that is accessible, intuitive, and clinically relevant.

The REDUCE metagram: a comprehensive prediction tool for determining the utility of dutasteride chemoprevention in men at risk for prostate cancer

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Nguyen, Carvell T.; Isariyawongse, Brandon [Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic Foundation, Cleveland, OH (United States); Yu, Changhong; Kattan, Michael W., E-mail: kattanm@ccf.org [Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, OH (United States)

2012-10-11

Introduction: 5-alpha reductase inhibitors can reduce the risk of prostate cancer (PCa) but can be associated with significant side effects. A library of nomograms which predict the risk of clinical endpoints relevant to dutasteride treatment may help determine if chemoprevention is suited to the individual patient. Methods: Data from the REDUCE trial was used to identify predictive factors for 9 endpoints relevant to dutasteride treatment. Using the treatment and placebo groups from the biopsy cohort, Cox proportional hazards (PH) and competing risks regression (CRR) models were used to build 18 nomograms, whose predictive ability was measured by concordance index (CI) and calibration plots. Results: A total of 18 nomograms assessing the risks of cancer, high grade cancer, high grade prostatic intraepithelial neoplasia (HGPIN), atypical small acinar proliferation (ASAP), erectile dysfunction (ED), acute urinary retention (AUR), gynecomastia, urinary tract infection (UTI) and BPH-related surgery either on or off dutasteride were created. The nomograms for cancer, high grade cancer, ED, AUR, and BPH-related surgery demonstrated good discrimination and calibration while those for gynecomastia, UTI, HGPIN, and ASAP predicted no better than random chance. Conclusions: To aid patients in determining whether the benefits of dutasteride use outweigh the risks, we have developed a comprehensive metagram that can generate individualized risks of 9 outcomes relevant to men considering chemoprevention. Better models based on more predictive markers are needed for some of the endpoints but the current metagram demonstrates potential as a tool for patient counseling and decision-making that is accessible, intuitive, and clinically relevant.

The REDUCE metagram: a comprehensive prediction tool for determining the utility of dutasteride chemoprevention in men at risk for prostate cancer

International Nuclear Information System (INIS)

Nguyen, Carvell T.; Isariyawongse, Brandon; Yu, Changhong; Kattan, Michael W.

2012-01-01

Introduction: 5-alpha reductase inhibitors can reduce the risk of prostate cancer (PCa) but can be associated with significant side effects. A library of nomograms which predict the risk of clinical endpoints relevant to dutasteride treatment may help determine if chemoprevention is suited to the individual patient. Methods: Data from the REDUCE trial was used to identify predictive factors for 9 endpoints relevant to dutasteride treatment. Using the treatment and placebo groups from the biopsy cohort, Cox proportional hazards (PH) and competing risks regression (CRR) models were used to build 18 nomograms, whose predictive ability was measured by concordance index (CI) and calibration plots. Results: A total of 18 nomograms assessing the risks of cancer, high grade cancer, high grade prostatic intraepithelial neoplasia (HGPIN), atypical small acinar proliferation (ASAP), erectile dysfunction (ED), acute urinary retention (AUR), gynecomastia, urinary tract infection (UTI) and BPH-related surgery either on or off dutasteride were created. The nomograms for cancer, high grade cancer, ED, AUR, and BPH-related surgery demonstrated good discrimination and calibration while those for gynecomastia, UTI, HGPIN, and ASAP predicted no better than random chance. Conclusions: To aid patients in determining whether the benefits of dutasteride use outweigh the risks, we have developed a comprehensive metagram that can generate individualized risks of 9 outcomes relevant to men considering chemoprevention. Better models based on more predictive markers are needed for some of the endpoints but the current metagram demonstrates potential as a tool for patient counseling and decision-making that is accessible, intuitive, and clinically relevant.

Update on the chemopreventive effects of ginger and its phytochemicals.

Science.gov (United States)

Baliga, Manjeshwar Shrinath; Haniadka, Raghavendra; Pereira, Manisha Maria; D'Souza, Jason Jerome; Pallaty, Princy Louis; Bhat, Harshith P; Popuri, Sandhya

2011-07-01

The rhizomes of Zingiber officinale Roscoe (Zingiberaceae), commonly known as ginger, is one of the most widely used spice and condiment. It is also an integral part of many traditional medicines and has been extensively used in Chinese, Ayurvedic, Tibb-Unani, Srilankan, Arabic, and African traditional medicines, since antiquity, for many unrelated human ailments including common colds, fever, sore throats, vomiting, motion sickness, gastrointestinal complications, indigestion, constipation, arthritis, rheumatism, sprains, muscular aches, pains, cramps, hypertension, dementia, fever, infectious diseases, and helminthiasis. The putative active compounds are nonvolatile pungent principles, namely gingerols, shogaols, paradols, and zingerone. These compounds are some of the extensively studied phytochemicals and account for the antioxidant, anti-inflammatory, antiemetic, and gastroprotective activities. A number of preclinical investigations with a wide variety of assay systems and carcinogens have shown that ginger and its compounds possess chemopreventive and antineoplastic effects. A number of mechanisms have been observed to be involved in the chemopreventive effects of ginger. The cancer preventive activities of ginger are supposed to be mainly due to free radical scavenging, antioxidant pathways, alteration of gene expressions, and induction of apoptosis, all of which contribute towards decrease in tumor initiation, promotion, and progression. This review provides concise information from preclinical studies with both cell culture models and relevant animal studies by focusing on the mechanisms responsible for the chemopreventive action. The conclusion describes directions for future research to establish its activity and utility as a human cancer preventive and therapeutic drug. The above-mentioned mechanisms of ginger seem to be promising for cancer prevention; however, further clinical studies are warranted to assess the efficacy and safety of ginger.

Pomegranate exerts chemoprevention of experimentally induced mammary tumorigenesis by suppression of cell proliferation and induction of apoptosis.

Science.gov (United States)

Bishayee, Anupam; Mandal, Animesh; Bhattacharyya, Piyali; Bhatia, Deepak

2016-01-01

Breast cancer is the second leading cause of cancer-related death in women in the United States and discovery and development of safe chemopreventive drugs is urgently needed. The fruit pomegranate (Punica granatum) is gaining importance because of its various health benefits. This study was initiated to investigate chemopreventive potential of a pomegranate emulsion (PE) against 7,12-dimethylbenz(a)anthracene (DMBA) rat mammary carcinogenesis. The animals were orally administered with PE (0.2-5.0 g/kg), starting 2 wk before and 16 wk following DMBA treatment. PE exhibited a striking reduction of DMBA-induced mammary tumor incidence, total tumor burden, and reversed histopathological changes. PE dose-dependently suppressed cell proliferation and induced apoptosis in mammary tumors. Immunohistochemical studies showed that PE increased intratumor Bax, decreased Bcl2 and manifested a proapoptotic shift in Bax/Bcl2 ratio. In addition, our gene expression study showed PE-mediated upregulation of Bad, caspase-3, caspase-7, caspase-9, poly (ADP ribose) polymerase and cytochrome c in mammary tumors. Thus, PE exerts chemoprevention of mammary carcinogenesis by suppressing cell proliferation and inducing apoptosis mediated through upregulation of Bax and downregulation of Bcl2 in concert with caspase cascades. Pomegranate bioactive phytoconstituents could be developed as a chemopreventive drug to reduce the risk of breast cancer.

Changes of initiation, promotion and metastatic enzyme system in human breast cancer with the proton irradiation

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Sohn, Y. H.; Kim, S. W.; Lee, K. S.; Mo, J. Y. [Dongguk University, Seoul (Korea, Republic of)

2010-04-15

Proton irradiations in the cells were significantly decreased cell viability but increased the QR activity in a dose-dependent manner. Cell viability was 92.3%, 88.4%, 81.8%, 72.4%, 68.9% at doses of 0.5, 2, 8, 16, and 32 Gy, respectively. At doses of 2, 8, 16, and 32 Gy, QR activity was increased 1.27-, 1.31-, 1.45- and 2.08-fold. However, negligible GST activity in the cells was detected and the activity was not changed by proton irradiation. Proton irradiation also increased GSH contents by 1.18- and 1.21-fold at doses of 0.5 and 2 Gy. In contrast, the ODC activity, a key enzyme in polyamine biosynthesis and tumor promotion, was decreased in a dose-dependent manner. We also investigated anti-metastatic effects of proton beam irradiation in breast cancer cells. Invasion and wound healing assay showed that metastatic activities in breast cancer cells were significantly decreased in a dose-dependent manner by proton beam irradiation. In zymography of MMP-9, the activity was slightly diminished. These results suggest that breast cancer chemopreventive potential was increased with proton irradiation by increasing the QR activity and the GSH levels and by inhibiting the ODC activity.

Changes of initiation, promotion and metastatic enzyme system in human breast cancer with the proton irradiation

International Nuclear Information System (INIS)

Sohn, Y. H.; Kim, S. W.; Lee, K. S.; Mo, J. Y.

2010-04-01

Proton irradiations in the cells were significantly decreased cell viability but increased the QR activity in a dose-dependent manner. Cell viability was 92.3%, 88.4%, 81.8%, 72.4%, 68.9% at doses of 0.5, 2, 8, 16, and 32 Gy, respectively. At doses of 2, 8, 16, and 32 Gy, QR activity was increased 1.27-, 1.31-, 1.45- and 2.08-fold. However, negligible GST activity in the cells was detected and the activity was not changed by proton irradiation. Proton irradiation also increased GSH contents by 1.18- and 1.21-fold at doses of 0.5 and 2 Gy. In contrast, the ODC activity, a key enzyme in polyamine biosynthesis and tumor promotion, was decreased in a dose-dependent manner. We also investigated anti-metastatic effects of proton beam irradiation in breast cancer cells. Invasion and wound healing assay showed that metastatic activities in breast cancer cells were significantly decreased in a dose-dependent manner by proton beam irradiation. In zymography of MMP-9, the activity was slightly diminished. These results suggest that breast cancer chemopreventive potential was increased with proton irradiation by increasing the QR activity and the GSH levels and by inhibiting the ODC activity.

Chemopreventive potential of β-Sitosterol in experimental colon cancer model - an In vitro and In vivo study

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Paulraj Gabriel M

2010-06-01

Full Text Available Abstract Background Asclepias curassavica Linn. is a traditional medicinal plant used by tribal people in the western ghats, India, to treat piles, gonorrhoea, roundworm infestation and abdominal tumours. We have determined the protective effect of β-sitosterol isolated from A. curassavica in colon cancer, using in vitro and in vivo models. Methods The active molecule was isolated, based upon bioassay guided fractionation, and identified as β-sitosterol on spectral evidence. The ability to induce apoptosis was determined by its in vitro antiradical activity, cytotoxic studies using human colon adenocarcinoma and normal monkey kidney cell lines, and the expression of β-catenin and proliferating cell nuclear antigen (PCNA in human colon cancer cell lines (COLO 320 DM. The chemopreventive potential of β-sitosterol in colon carcinogenesis was assessed by injecting 1,2-dimethylhydrazine (DMH, 20 mg/kg b.w. into male Wistar rats and supplementing this with β-sitosterol throughout the experimental period of 16 weeks at 5, 10, and 20 mg/kg b.w. Results β-sitosterol induced significant dose-dependent growth inhibition of COLO 320 DM cells (IC50 266.2 μM, induced apoptosis by scavenging reactive oxygen species, and suppressed the expression of β-catenin and PCNA antigens in human colon cancer cells. β-sitosterol supplementation reduced the number of aberrant crypt and crypt multiplicity in DMH-initiated rats in a dose-dependent manner with no toxic effects. Conclusion We found doses of 10-20 mg/kg b.w. β-sitosterol to be effective for future in vivo studies. β-sitosterol had chemopreventive potential by virtue of its radical quenching ability in vitro, with minimal toxicity to normal cells. It also attenuated β-catenin and PCNA expression, making it a potential anticancer drug for colon carcinogenesis.

Chemopreventive potential of β-Sitosterol in experimental colon cancer model - an In vitro and In vivo study

Science.gov (United States)

2010-01-01

Background Asclepias curassavica Linn. is a traditional medicinal plant used by tribal people in the western ghats, India, to treat piles, gonorrhoea, roundworm infestation and abdominal tumours. We have determined the protective effect of β-sitosterol isolated from A. curassavica in colon cancer, using in vitro and in vivo models. Methods The active molecule was isolated, based upon bioassay guided fractionation, and identified as β-sitosterol on spectral evidence. The ability to induce apoptosis was determined by its in vitro antiradical activity, cytotoxic studies using human colon adenocarcinoma and normal monkey kidney cell lines, and the expression of β-catenin and proliferating cell nuclear antigen (PCNA) in human colon cancer cell lines (COLO 320 DM). The chemopreventive potential of β-sitosterol in colon carcinogenesis was assessed by injecting 1,2-dimethylhydrazine (DMH, 20 mg/kg b.w.) into male Wistar rats and supplementing this with β-sitosterol throughout the experimental period of 16 weeks at 5, 10, and 20 mg/kg b.w. Results β-sitosterol induced significant dose-dependent growth inhibition of COLO 320 DM cells (IC50 266.2 μM), induced apoptosis by scavenging reactive oxygen species, and suppressed the expression of β-catenin and PCNA antigens in human colon cancer cells. β-sitosterol supplementation reduced the number of aberrant crypt and crypt multiplicity in DMH-initiated rats in a dose-dependent manner with no toxic effects. Conclusion We found doses of 10-20 mg/kg b.w. β-sitosterol to be effective for future in vivo studies. β-sitosterol had chemopreventive potential by virtue of its radical quenching ability in vitro, with minimal toxicity to normal cells. It also attenuated β-catenin and PCNA expression, making it a potential anticancer drug for colon carcinogenesis. PMID:20525330

Chemopreventive and therapeutic activity of dietary blueberry against estrogen-mediated breast cancer.

Science.gov (United States)

Jeyabalan, Jeyaprakash; Aqil, Farrukh; Munagala, Radha; Annamalai, Lakshmanan; Vadhanam, Manicka V; Gupta, Ramesh C

2014-05-07

Berries are gaining increasing importance lately for their chemopreventive and therapeutic potential against several cancers. In earlier studies, a blueberry-supplemented diet has shown protection against 17β-estradiol (E2)-mediated mammary tumorigenesis. This study tested both preventive and therapeutic activities of diet supplemented with whole blueberry powder (50:50 blend of Tifblue and Rubel). Animals received 5% blueberry diet, either 2 weeks prior to or 12 weeks after E2 treatment in preventive and therapeutic groups, respectively. Both interventions delayed the tumor latency for palpable mammary tumors by 28 and 37 days, respectively. Tumor volume and multiplicity were also reduced significantly in both modes. The effect on mammary tumorigenesis was largely due to down-regulation of CYP 1A1 and ER-α gene expression and also favorable modulation of microRNA (miR-18a and miR-34c) levels. These data suggest that the blueberry blend tested is effective in inhibiting E2-mediated mammary tumorigenesis in both preventive and therapeutic modes.

The intriguing role of fibroblasts and c-Jun in the chemopreventive and therapeutic effect of finasteride on xenograft models of prostate cancer

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Yi-Nong Niu

2016-01-01

Full Text Available In a large clinical trial, finasteride reduced the rate of low-grade prostate cancer (PCa while increasing the incidence of high-grade cancer. Whether finasteride promotes the development of high-grade tumors remains controversial. We demonstrated the role of fibroblasts and c-Jun in chemopreventive and therapeutic effect of finasteride on xenograft models of PCa. LNCaP (PC3 cells or recombinants of cancer cells and fibroblasts were implanted in male athymic nude mice treated with finasteride. Tumor growth, cell proliferation, apoptosis, p-Akt, and p-ERK1/2 were evaluated. In LNCaP (PC3 mono-grafted models, finasteride did not change the tumor growth. In recombinant-grafted models, fibroblasts and c-Jun promoted tumor growth; finasteride induced proliferation of LNCaP cells and repressed PC3 cell apoptosis. When c-Jun was knocked out, fibroblasts and/or finasteride did not promote the tumor growth. Finasteride inhibited p-Akt and p-ERK1/2 in mono-culture cancer cells while stimulating the same signaling molecules in the presence of fibroblasts. Reduced p-Akt and p-ERK1/2 were noted in the presence of c-Jun−/− fibroblasts. Fibroblasts and c-Jun promote PCa growth; finasteride further stimulates tumor growth with promoted proliferation, repressed apoptosis, and up-regulated pro-proliferative molecular pathway in the presence of fibroblasts and c-Jun. Stromal-epithelial interactions play critical roles in finasteride′s therapeutic effects on PCa. Our findings have preliminary implications in using finasteride as a chemopreventive or therapeutic agent for PCa patients.

Sirt1 Is Required for Resveratrol-Mediated Chemopreventive Effects in Colorectal Cancer Cells

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Constanze Buhrmann

2016-03-01

Full Text Available Sirt1 is a NAD+-dependent protein-modifying enzyme involved in regulating gene expression, DNA damage repair, metabolism and survival, as well as acts as an important subcellular target of resveratrol. The complex mechanisms underlying Sirt1 signaling during carcinogenesis remain controversial, as it can serve both as a tumor promoter and suppressor. Whether resveratrol-mediated chemopreventive effects are mediated via Sirt1 in CRC growth and metastasis remains unclear; which was the subject of this study. We found that resveratrol suppressed proliferation and invasion of two different human CRC cells in a dose-dependent manner, and interestingly, this was accompanied with a significant decrease in Ki-67 expression. By transient transfection of CRC cells with Sirt1-ASO, we demonstrated that the anti-tumor effects of resveratrol on cells was abolished, suggesting the essential role of this enzyme in the resveratrol signaling pathway. Moreover, resveratrol downregulated nuclear localization of NF-κB, NF-κB phosphorylation and its acetylation, causing attenuation of NF-κB-regulated gene products (MMP-9, CXCR4 involved in tumor-invasion and metastasis. Finally, Sirt1 was found to interact directly with NF-κB, and resveratrol did not suppress Sirt1-ASO-induced NF-κB phosphorylation, acetylation and NF-κB-regulated gene products. Overall, our results demonstrate that resveratrol can suppress tumorigenesis, at least in part by targeting Sirt1 and suppression of NF-κB activation.

Chemopreventive Potential of Powdered Red Wine Pomace Seasonings against Colorectal Cancer in HT-29 Cells.

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Del Pino-García, Raquel; Rivero-Pérez, María D; González-SanJosé, María L; Ortega-Heras, Miriam; García Lomillo, Javier; Muñiz, Pilar

2017-01-11

This study evaluates the antiproliferative and antigenotoxic actions of powdered red wine pomace seasonings (Sk-S, seedless; W-S, whole; Sd-S, seeds). In vitro gastrointestinal digested and colonic fermented fractions of the seasonings were used as cell treatments. Phenolic acids from Sk-S showed the highest bioaccessibility in the small intestine, whereas polyphenols contained in Sd-S might be the most fermentable in the colon. Dietary fiber from Sk-S was the best substrate for short chain fatty acids production by gut microbiota. Colon cancerous (HT-29) cell viability was inhibited by 50% (IC 50 values) at treatment concentrations ranging from 845 (Sk-S) to 1085 (Sd-S) μg/mL prior digestion, but all digested fractions exhibited similar antiproliferative activities (mean IC 50 = 814 μg/mL). Oxidative DNA damage in cells was also attenuated by the treatments (200 μg/mL, 24 h preincubation), with all colonic fermented fractions displaying similar genoprotective action. These results suggest the potential of red wine pomace seasonings as chemopreventive agents in colorectal cancer.

Flavonoids as modulators of metabolic enzymes and drug transporters.

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Miron, Anca; Aprotosoaie, Ana Clara; Trifan, Adriana; Xiao, Jianbo

2017-06-01

Flavonoids, natural compounds found in plants and in plant-derived foods and beverages, have been extensively studied with regard to their capacity to modulate metabolic enzymes and drug transporters. In vitro, flavonoids predominantly inhibit the major phase I drug-metabolizing enzyme CYP450 3A4 and the enzymes responsible for the bioactivation of procarcinogens (CYP1 enzymes) and upregulate the enzymes involved in carcinogen detoxification (UDP-glucuronosyltransferases, glutathione S-transferases (GSTs)). Flavonoids have been reported to inhibit ATP-binding cassette (ABC) transporters (multidrug resistance (MDR)-associated proteins, breast cancer-resistance protein) that contribute to the development of MDR. P-glycoprotein, an ABC transporter that limits drug bioavailability and also induces MDR, was differently modulated by flavonoids. Flavonoids and their phase II metabolites (sulfates, glucuronides) inhibit organic anion transporters involved in the tubular uptake of nephrotoxic compounds. In vivo studies have partially confirmed in vitro findings, suggesting that the mechanisms underlying the modulatory effects of flavonoids are complex and difficult to predict in vivo. Data summarized in this review strongly support the view that flavonoids are promising candidates for the enhancement of oral drug bioavailability, chemoprevention, and reversal of MDR. © 2017 New York Academy of Sciences.

Designing the selenium and bladder cancer trial (SELEBLAT, a phase lll randomized chemoprevention study with selenium on recurrence of bladder cancer in Belgium

Directory of Open Access Journals (Sweden)

Goossens Maria E

2012-03-01

Full Text Available Abstract Background In Belgium, bladder cancer is the fifth most common cancer in males (5.2% and the sixth most frequent cause of death from cancer in males (3.8%. Previous epidemiological studies have consistently reported that selenium concentrations were inversely associated with the risk of bladder cancer. This suggests that selenium may also be suitable for chemoprevention of recurrence. Method The SELEBLAT study opened in September 2009 and is still recruiting all patients with non-invasive transitional cell carcinoma of the bladder on TURB operation in 15 Belgian hospitals. Recruitment progress can be monitored live at http://www.seleblat.org. Patients are randomly assigned to selenium yeast (200 μg/day supplementation for 3 years or matching placebo, in addition to standard care. The objective is to determine the effect of selenium on the recurrence of bladder cancer. Randomization is stratified by treatment centre. A computerized algorithm randomly assigns the patients to a treatment arm. All study personnel and participants are blinded to treatment assignment for the duration of the study. Design The SELEnium and BLAdder cancer Trial (SELEBLAT is a phase III randomized, placebo-controlled, academic, double-blind superior trial. Discussion This is the first report on a selenium randomized trial in bladder cancer patients. Trial registration ClinicalTrials.gov identifier: NCT00729287

Chemoprevention of colorectal cancer by black raspberry anthocyanins involved the modulation of gut microbiota and SFRP2 demethylation.

Science.gov (United States)

Chen, Lili; Jiang, Bowen; Zhong, Chunge; Guo, Jun; Zhang, Lihao; Mu, Teng; Zhang, Qiuhua; Bi, Xiuli

2018-03-08

Freeze-dried black raspberry (BRB) powder is considered as a potential cancer chemopreventive agent. In this study, we fed azoxymethane (AOM)/dextran sodium sulfate (DSS)-treated C57BL/6J mice with a diet containing BRB anthocyanins for 12 weeks, and this led to a reduction in colon carcinogenesis. These animals had consistently lower tumor multiplicity compared with AOM/DSS-treated mice not receiving BRB anthocyanins. In AOM/DSS-treated mice, the number of pathogenic bacteria, including Desulfovibrio sp. and Enterococcus spp., was increased significantly, whereas probiotics such as Eubacterium rectale, Faecalibacterium prausnitzii and Lactobacillus were dramatically decreased, but BRB anthocyanins supplement could reverse this imbalance in gut microbiota. BRB anthocyanins also caused the demethylation of the SFRP2 gene promoter, resulting in increased expression of SFRP2, both at the mRNA and protein levels. Furthermore, the expression levels of DNMT31 and DNMT3B, as well as of p-STAT3 were downregulated by BRB anthocyanins in these animals. Taken together, these results suggested that BRB anthocyanins could modulate the composition of gut commensal microbiota, and changes in inflammation and the methylation status of the SFRP2 gene may play a central role in the chemoprevention of CRC.

Flavin-Dependent Enzymes in Cancer Prevention

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Danuta Wojcieszyńska

2012-12-01

Full Text Available Statistical studies have demonstrated that various agents may reduce the risk of cancer’s development. One of them is activity of flavin-dependent enzymes such as flavin-containing monooxygenase (FMOGS-OX1, FAD-dependent 5,10-methylenetetrahydrofolate reductase and flavin-dependent monoamine oxidase. In the last decade, many papers concerning their structure, reaction mechanism and role in the cancer prevention were published. In our work, we provide a more in-depth analysis of flavin-dependent enzymes and their contribution to the cancer prevention. We present the actual knowledge about the glucosinolate synthesized by flavin-containing monooxygenase (FMOGS-OX1 and its role in cancer prevention, discuss the influence of mutations in FAD-dependent 5,10-methylenetetrahydrofolate reductase on the cancer risk, and describe FAD as an important cofactor for the demethylation of histons. We also present our views on the role of riboflavin supplements in the prevention against cancer.

The neem limonoids azadirachtin and nimbolide inhibit hamster cheek pouch carcinogenesis by modulating xenobiotic-metabolizing enzymes, DNA damage, antioxidants, invasion and angiogenesis.

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Priyadarsini, Ramamurthi Vidya; Manikandan, Palrasu; Kumar, Gurram Harish; Nagini, Siddavaram

2009-05-01

The neem tree has attracted considerable research attention as a rich source of limonoids that have potent antioxidant and anti-cancer properties. The present study was designed to evaluate the chemopreventive potential of the neem limonoids azadirachtin and nimbolide based on in vitro antioxidant assays and in vivo inhibitory effects on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis. Both azadirachtin and nimbolide exhibited concentration-dependent anti-radical scavenging activity and reductive potential in the order: nimbolide > azadirachtin > ascorbate. Administration of both azadirachtin and nimbolide inhibited the development of DMBA-induced HBP carcinomas by influencing multiple mechanisms including prevention of procarcinogen activation and oxidative DNA damage, upregulation of antioxidant and carcinogen detoxification enzymes and inhibition of tumour invasion and angiogenesis. On a comparative basis, nimbolide was found to be a more potent antioxidant and chemopreventive agent and offers promise as a candidate agent in multitargeted prevention and treatment of cancer.

Regulations of enzymes in animals: effects of developmental processes, cancer, and radiation. Final report. [Analysis of enzymes in human cancer tissue

Energy Technology Data Exchange (ETDEWEB)

Knox, W.E.

1978-09-01

Low grade tumors of various origins are chemically very different. High grade tumors, whatever their origin, are chemically very similar to one another and to embryonic tissues. Analyses of human tumor tissues and sera from cancer patients were conducted for two new groups of enzymes expected to be informative about the physiological state of the tissue. The enzymes measured in tumors and sera were chosen because they were characteristic of fetal tissues and high grade neoplasms in rats, and could, therefore, be expected to exist in human cancers (and fetuses) and to predominate more in those of higher grade malignancies. Results indicated that the classification of enzymes (or isozymes) as fetal or adult types in the rat could be extended to man. Human cancers do contain most of the enzymes expected, and lack others, as expected. Analyses of the same enzymes in sera gave less clear results. It was recognized at the outset that no simple proportionality existed between tissue and serum levels. The tendency existed in cancer patients to have in serum elevated amounts of those enzymes characteristic of undifferentiated tissues. The abnormalities in a specific patient are conditioned by his physiological state, by the grade of his tumor, and by the mass of tumor present. The tumor mass had a very significant effect, so that monitoring this tumor burden by chemical means should be quite possible. The latest work focused on particular enzymes that have not previously been measured in cancer patients. These studies concentrated on pyrroline-5-carboxylate (P-5-C) reductase and its inhibition and on lysosomal glucosidases and phosphatases. Both groups are relatively high in fetal and neoplastic tissues.

In vitro chemopreventive properties of peptides released from quinoa (Chenopodium quinoa Willd.) protein under simulated gastrointestinal digestion.

Science.gov (United States)

Vilcacundo, Rubén; Miralles, Beatriz; Carrillo, Wilman; Hernández-Ledesma, Blanca

2018-03-01

Because of the continuous and direct interaction between the digestive tract and foods, dietary compounds represent an interesting source of chemopreventive agents for gastrointestinal health. In this study, the influence of a standardized static in vitro gastrointestinal digestion model on the release of peptides with chemopreventive potential from quinoa protein was investigated. Gastroduodenal digests and fractions collected by ultrafiltration were evaluated for their in plate oxygen radical absorbance capacity and in vitro colon cancer cell viability inhibitory activity. Highest effects were observed in the digests obtained during the intestinal phase, with fraction containing peptides 5kDa showing the greatest anti-cancer effects. Seventeen potential bioactive peptides derived from quinoa proteins have been identified. These proteins might be utilized as new ingredients in the development of functional foods or nutraceuticals with the aim of reducing oxidative stress-associated diseases, including cancer. Copyright © 2017 Elsevier Ltd. All rights reserved.

Natural chemopreventive alternatives in oral cancer chemoprevention.

Science.gov (United States)

Scrobota, I; Bolfa, P; Filip, A G; Catoi, C; Alb, C; Pop, O; Tatomir, C; Baciut, G

2016-02-01

We studied the effect of grape seed extract Burgund Mare (BM) on oral carcinogenesis and compared it with that of curcumin (CU). Wistar rats were divided into six groups (n = 10): 4-nitro-quinoline-1-oxide (4NQO) oral carcinogenesis was induced to groups 1 - 5; groups 2 and 3 received BM and CU respectively during initiation and groups 4 and 5 BM and CU during post-initiation of carcinogenesis; group 6 represented the negative control group. Total malondialdehyde (MDA) and reduced glutathione (GSH) were assayed fluorometrically in oral tissue (gingival, jugal, palatal, lingual mucosa) and serum. Histopathological exam was performed and a dysplasia score given to each oral mucosal lesion. Ki67, cyclin D1, p63, Bcl2 and p53 were immunohistochemically evaluated. BM and CU reduced tissue MDA values elevated by 4NQO (P = 0.000). The difference between CU and BM effect was significant in the initiation (P = 0.02) but not in the post-initiation phase of carcinogenesis (P = 0.58). Tissue GSH levels decreased by 4NQO (P < 0.001) were not significantly modified by BM or CU. Serum MDA levels increased by 4NQO (P = 0.000) were significantly lowered by CU (P = 0.04) and BM (P = 0.04) during initiation and by CU during post-initiation of carcinogenesis (P = 0.01). CU was more potent than BM during post-initiation of carcinogenesis (P = 0.01). Serum GSH lowered by 4NQO (P = 0.55) was significantly decreased by BM and CU (P < 0.012), with no significant difference between groups receiving BM or CU. Moderate dysplasia was the most advanced dysplasia induced and gingival localization the most frequent. Both BM and CU lowered dysplasia scores, with BM being the most efficient during post-initiation of carcinogenesis (P = 0.001). Ki67, cyclin D1, p63, Bcl2 and p53 expression increased with dysplasia scores. BM showed chemopreventive properties during initiation and post-initiation of oral carcinogenesis, reducing local and general oxidative stress and the intensity of dysplasia

Nanoemulsions of cancer chemopreventive agent benzyl isothiocyanate display enhanced solubility, dissolution, and permeability.

Science.gov (United States)

Qhattal, Hussaini Syed Sha; Wang, Shu; Salihima, Tri; Srivastava, Sanjay K; Liu, Xinli

2011-12-14

Benzyl isothiocyanate (BITC), a compound found in cruciferous vegetables, is an effective chemopreventive agent. The objective of this study was to develop nanoemulsion formulations for the oral delivery of BITC. Optimized oil-in-water BITC nanoemulsions were prepared by a spontaneous self-nanoemulsification method and a homogenization-sonication method. Both nanoemulsions entrapped high amounts of BITC (15-17 mg/mL), with low polydispersity and good colloidal stability. The BITC nanoemulsions showed enhanced solubility and dissolution compared to pure BITC. These formulations markedly increased the apical to basolateral transport of BITC in Caco-2 cell monolayers. The apparent permeability values were 3.6 × 10(-6) cm/s for pure BITC and (1.1-1.3) × 10(-5) cm/s for BITC nanoemulsions. The nanoemulsions were easily taken up by human cancer cells A549 and SKOV-3 and inhibited tumor growth in vitro. This work shows for the first time that BITC can be formulated into nanoemulsions and may show promise in enhancing absorption and bioavailability.

Nitrates and NO-NSAIDs in Cancer Chemoprevention & Therapy: In Vitro Evidence Querying the NO Donor Functionality

Science.gov (United States)

Dunlap, Tareisha; Abdul-Hay, Samer; Chandrasena, R. Esala P.; Hagos, Ghenet K; Sinha, Vaishali; Wang, Zhiqiang; Wang, Huali; Thatcher, Gregory R. J.

2008-01-01

Properties of the NO-ASA family of NO-donating NSAIDs (NO-NSAIDs), notably NCX 4016 (mNO-ASA) and NCX 4040 (pNO-ASA), reported in more than a hundred publications, have included positive preclinical data in cancer chemoprevention and therapy. Evidence is presented that the antiproliferative, the chemopreventive (antioxidant/electrophile response element (ARE) activation), and the anti-inflammatory activity of NO-ASA in cell cultures is replicated by X-ASA derivatives that are incapable of acting as NO donors. pBr-ASA and mBr-ASA are conisogenic with NO-ASA, but are not NO donors. The biological activity of pNO-ASA is replicated by pBr-ASA; and both pNO-ASA and pBr-ASA are bioactivated to the same quinone methide electrophile. The biological activity of mNO-ASA is replicated by mBr-ASA; mNO-ASA and mBr-ASA are bioactivated to different benzyl electrophiles. The observed activity is likely initiated by trapping of thiol biomolecules by the quinone and benzyl electrophiles, leading to depletion of GSH and modification of Cys-containing sensor proteins. Whereas all NO-NSAIDs containing the same structural “linker” as NCX 4040 and NCX 4016 are anticipated to possess activity resulting from bioactivation to electrophilic metabolites, this expectation does not extend to other linker structures. Nitrates require metabolic bioactivation to liberate NO bioactivity, which is often poorly replicated in vitro, and NO bioactivity provided by NO-NSAIDs in vivo provides proven therapeutic benefits in mitigation of NSAID gastrotoxicity. The in vivo properties of X-ASA drugs await discovery. PMID:18485921

Prevention of human cancer by modulation of chronic inflammatory processes

Energy Technology Data Exchange (ETDEWEB)

Ohshima, Hiroshi [International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon Cedex 08 (France)]. E-mail: ohshima@iarc.fr; Tazawa, Hiroshi [International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon Cedex 08 (France); Sylla, Bakary S. [International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon Cedex 08 (France); Sawa, Tomohiro [International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon Cedex 08 (France)

2005-12-11

Chronic inflammation induced by biological, chemical and physical factors has been associated with increased risk of human cancer at various sites. Inflammation facilitates the initiation of normal cells and their growth and progression to malignancy through production of pro-inflammatory cytokines and diverse reactive oxygen and nitrogen species. These also activate signaling molecules involved in inflammation and carcinogenesis such as nuclear transcription factor (NF-{kappa}B), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Several chemopreventive agents act through inhibition of signaling pathways (e.g. NF-{kappa}B), inhibition of oxidant-generating enzymes (e.g. iNOS) and mediators of inflammation (e.g. COX-2), scavenging reactive oxygen and nitrogen species, and modulation of xenobiotic-metabolizing enzymes (especially phase II enzyme induction). Some anti-inflammatory drugs have been tested in clinical trials to prevent human cancer at several sites. Better understanding of the molecular mechanisms by which chronic inflammation increases cancer risk will lead to further development of new strategies for cancer prevention at many sites.

Breast cancer prevention.

Science.gov (United States)

Euhus, David M; Diaz, Jennifer

2015-01-01

Breast cancer is the most common cancer in women with 232,670 new cases estimated in the USA for 2014. Approaches for reducing breast cancer risk include lifestyle modification, chemoprevention, and prophylactic surgery. Lifestyle modification has a variety of health benefits with few associated risks and is appropriate for all women regardless of breast cancer risk. Chemoprevention options have expanded rapidly, but most are directed at estrogen receptor positive breast cancer and uptake is low. Prophylactic surgery introduces significant additional risks of its own and is generally reserved for the highest risk women. © 2014 Wiley Periodicals, Inc.

Chemopreventive effect of tadalafil in cisplatin-induced ...

African Journals Online (AJOL)

Summary: Nephrotoxicity remains a common untoward effect of cisplatin therapy with limited effective chemopreventive options available till date. This study aims to evaluate the possible chemopreventive effect and mechanism(s) of action of 2 mgkg-1 and 5 mgkg-1 of Tadalafil in cisplatin-induced nephrotoxic rats. In this ...

Chemopreventive Effects of Oplopantriol A, a Novel Compound Isolated from Oplopanax horridus, on Colorectal Cancer

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Zhiyu Zhang

2014-07-01

Full Text Available Oplopanax horridus is a North American botanical that has received limited investigations. We previously isolated over a dozen of the constituents from O. horridus, and among them oplopantriol A (OPT A is a novel compound. In this study, we firstly evaluated the in vivo chemoprevention activities of OPT A using the xenograft colon cancer mouse model. Our data showed that this compound significantly suppressed tumor growth with dose-related effects (p < 0.01. Next, we characterized the compound’s growth inhibitory effects in human colorectal cancer cell lines HCT-116 and SW-480. With OPT A treatment, these malignant cells were significantly inhibited in both a concentration- and time-dependent manner (both p < 0.01. The IC50 was approximately 5 µM for HCT-116 and 7 µM for SW-480 cells. OPT A significantly induced apoptosis and arrested the cell cycle at the G2/M phase. From further mechanism explorations, our data showed that OPT A significantly upregulated the expression of a cluster of genes, especially the tumor necrosis factor receptor family and caspase family, suggesting that the tumor necrosis factor-related apoptotic pathway plays a key role in OPT A induced apoptosis.

Teriflunomide (Leflunomide Promotes Cytostatic, Antioxidant, and Apoptotic Effects in Transformed Prostate Epithelial Cells: Evidence Supporting a Role for Teriflunomide in Prostate Cancer Chemoprevention

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Numsen Hail, Jr

2010-06-01

Full Text Available Teriflunomide (TFN is an inhibitor of de novo pyrimidine synthesis and the active metabolite of leflunomide. Leflunomide is prescribed to patients worldwide as an immunomodulatory and anti-inflammatory disease-modifying prodrug. Leflunomide inhibited the growth of human prostate cancer xenographs in mice, and leflunomide or TFN promoted cytostasis and/or apoptosis in cultured cells. These findings suggest that TFN could be useful in prostate cancer chemoprevention. We investigated the possible mechanistic aspects of this tenet by characterizing the effects of TFN using premalignant PWR-1E and malignant DU-145 human prostate epithelial cells. TFN promoted a dose- and time-dependent cytostasis or apoptosis induction in these cells. The cytostatic effects of TFN, which were reversible but not by the presence of excess uridine in the culture medium, included diminished cellular uridine levels, an inhibition in oxygen consumption, a suppression of reactive oxygen species (ROS generation, S-phase cell cycle arrest, and a conspicuous reduction in the size and number of the nucleoli in the nuclei of these cells. Conversely, TFN's apoptogenic effects were characteristic of catastrophic mitochondrial disruption (i.e., a dissipation of mitochondrial inner transmembrane potential, enhanced ROS production, mitochondrial cytochrome c release, and cytoplasmic vacuolization and followed by DNA fragmentation. The respiration-deficient derivatives of the DU-145 cells, which are also uridine auxotrophs, were markedly resistant to the cytostatic and apoptotic effects of TFN, implicating de novo pyrimidine synthesis and mitochondrial bioenergetics as the primary targets for TFN in the respiration competent cells. These mechanistic findings advocate a role for TFN and mitochondrial bioenergetics in prostate cancer chemoprevention.

Chemotherapeutic prevention studies of prostate cancer

DEFF Research Database (Denmark)

Djavan, Bob; Zlotta, Alexandre; Schulman, Claude

2004-01-01

Despite advances in the detection and management of prostate cancer, this disease remains a major cause of morbidity and mortality in men. Increasing attention has focused on the role of chemoprevention for prostate cancer, ie the administration of agents that inhibit 1 or more steps in the natural...... history of prostate carcinogenesis. We review prostate cancer chemoprevention studies in Europe....

Nitrates and NO-NSAIDs in cancer chemoprevention and therapy: in vitro evidence querying the NO donor functionality.

Science.gov (United States)

Dunlap, Tareisha; Abdul-Hay, Samer O; Chandrasena, R Esala P; Hagos, Ghenet K; Sinha, Vaishali; Wang, Zhiqiang; Wang, Huali; Thatcher, Gregory R J

2008-09-01

Properties of the NO-ASA family of NO-donating NSAIDs (NO-NSAIDs), notably NCX 4016 (mNO-ASA) and NCX 4040 (pNO-ASA), reported in more than one hundred publications, have included positive preclinical data in cancer chemoprevention and therapy. Evidence is presented that the antiproliferative, the chemopreventive (antioxidant/electrophile response element (ARE) activation), and the anti-inflammatory activity of NO-ASA in cell cultures is replicated by X-ASA derivatives that are incapable of acting as NO donors. pBr-ASA and mBr-ASA are conisogenic with NO-ASA, but are not NO donors. The biological activity of pNO-ASA is replicated by pBr-ASA; and both pNO-ASA and pBr-ASA are bioactivated to the same quinone methide electrophile. The biological activity of mNO-ASA is replicated by mBr-ASA; mNO-ASA and mBr-ASA are bioactivated to different benzyl electrophiles. The observed activity is likely initiated by trapping of thiol biomolecules by the quinone and benzyl electrophiles, leading to depletion of GSH and modification of Cys-containing sensor proteins. Whereas all NO-NSAIDs containing the same structural "linker" as NCX 4040 and NCX 4016 are anticipated to possess activity resulting from bioactivation to electrophilic metabolites, this expectation does not extend to other linker structures. Nitrates require metabolic bioactivation to liberate NO bioactivity, which is often poorly replicated in vitro, and NO bioactivity provided by NO-NSAIDs in vivo provides proven therapeutic benefits in mitigation of NSAID gastrotoxicity. The in vivo properties of X-ASA drugs await discovery.

The chemopreventive action of bromelain, from pineapple stem (Ananas comosus L.), on colon carcinogenesis is related to antiproliferative and proapoptotic effects.

Science.gov (United States)

Romano, Barbara; Fasolino, Ines; Pagano, Ester; Capasso, Raffaele; Pace, Simona; De Rosa, Giuseppe; Milic, Natasa; Orlando, Pierangelo; Izzo, Angelo A; Borrelli, Francesca

2014-03-01

Colorectal cancer is an important health problem across the world. Here, we investigated the possible antiproliferative/proapoptotic effects of bromelain (from the pineapple stem Ananas comosus L., family Bromeliaceae) in a human colorectal carcinoma cell line and its potential chemopreventive effect in a murine model of colon cancer. Proliferation and apoptosis were evaluated in human colon adenocarcinoma (Caco-2) cells by the (3) H-thymidine incorporation assay and caspase 3/7 activity measurement, respectively. Extracellular signal-related kinase (ERK) and Akt expression were evaluated by Western blot analysis, reactive oxygen species production by a fluorimetric method. In vivo, bromelain was evaluated using the azoxymethane murine model of colon carcinogenesis. Bromelain reduced cell proliferation and promoted apoptosis in Caco-2 cells. The effect of bromelain was associated to downregulation of pERK1/2/total, ERK, and pAkt/Akt expression as well as to reduction of reactive oxygen species production. In vivo, bromelain reduced the development of aberrant crypt foci, polyps, and tumors induced by azoxymethane. Bromelain exerts antiproliferative and proapoptotic effects in colorectal carcinoma cells and chemopreventive actions in colon carcinogenesis in vivo. Bromelain-containing foods and/or bromelain itself may represent good candidates for colorectal cancer chemoprevention. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pharmacokinetics of Dietary Cancer Chemopreventive Compound Dibenzoylmethane in the Rats and Impacts of Nanoemulsion and Genetic knockout of Nrf2 on its Disposition

OpenAIRE

Lin, Wen; Hong, Jin-Liern; Shen, Guoxiang; Wu, Rachel T.; Wu, Yuwen; Huang, Mou-Tuan; Newmark, Harold L.; Huang, Qingrong; Khor, Tin Oo; Heimbach, Tycho; Kong, Ah-Ng

2010-01-01

The pharmacokinetic disposition of a dietary cancer chemopreventive compound dibenzoylmethane (DBM) was studied in male Sprague-Dawley rats after intravenous (i.v.) and oral (p.o.) administrations. Following a single i.v. bolus dose, the mean plasma clearance (CL) of DBM was low as compared to the hepatic blood flow. DBM displayed a high volume of distribution (Vss). The elimination terminal t1/2 was long. The mean CL, Vss and AUC0-∞/dose were similar between the i.v. 10 and 10 mg/kg doses. A...

Metabolic enzymes: key modulators of functionality in cancer stem-like cells.

Science.gov (United States)

Dong, Bo-Wen; Qin, Guang-Ming; Luo, Yan; Mao, Jian-Shan

2017-02-21

Cancer Stem-like Cells (CSCs) are a subpopulation of cancer cells with self-renewal capacity and are important for the initiation, progression and recurrence of cancer diseases. The metabolic profile of CSCs is consistent with their stem-like properties. Studies have indicated that enzymes, the main regulators of cellular metabolism, dictate functionalities of CSCs in both catalysis-dependent and catalysis-independent manners. This paper reviews diverse studies of metabolic enzymes, and describes the effects of these enzymes on metabolic adaptation, gene transcription and signal transduction, in CSCs.

Intrinsic fluorescence biomarkers in cells treated with chemopreventive drugs

Science.gov (United States)

Kirkpatrick, Nathaniel D.; Brands, William R.; Zou, Changping; Brewer, Molly A.; Utzinger, Urs

2005-03-01

Non-invasive monitoring of cellular metabolism offers promising insights into areas ranging from biomarkers for drug activity to cancer diagnosis. Fluorescence spectroscopy can be utilized in order to exploit endogenous fluorophores, typically metabolic co-factors nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD), and estimate the redox status of the sample. Fluorescence spectroscopy was applied to follow metabolic changes in epithelial ovarian cells as well as bladder epithelial cancer cells during treatment with a chemopreventive drug that initiates cellular quiescence. Fluorescence signals consistent with NADH, FAD, and tryptophan were measured to monitor cellular activity, redox status, and protein content. Cells were treated with varying concentrations of N-4-(hydroxyphenyl) retinamide (4-HPR) and measured in a stable environment with a sensitive fluorescence spectrometer. A subset of measurements was completed on a low concentration of cells to demonstrate feasibility for medical application such as in bladder or ovary washes. Results suggest that all of the cells responded with similar dose dependence but started at different estimated redox ratio baseline levels correlating with cell cycle, growth inhibition, and apoptosis assays. NADH and tryptophan related fluorescence changed significantly while FAD related fluorescence remained unaltered. Fluorescence data collected from approximately 1000 - 2000 cells, comparable to a bladder or ovary wash, was measurable and useful for future experiments. This study suggests that future intrinsic biomarker measurements may need to be most sensitive to changes in NADH and tryptophan related fluorescence while using FAD related fluorescence to help estimate the baseline redox ratio and predict response to chemopreventive agents.

Scientific Evidence of Rice By-Products for Cancer Prevention: Chemopreventive Properties of Waste Products from Rice Milling on Carcinogenesis In Vitro and In Vivo

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Bee Ling Tan

2017-01-01

Full Text Available Cancer is a significant global health concern affecting men and women worldwide. Although current chemopreventive drugs could inhibit the growth of cancer cells, they exert many adverse side effects. Dietary factor plays a crucial role in the management of cancers and has drawn the attention of researchers to be used as an option to combat this disease. Both in vitro and in vivo studies showed that rice and its by-products display encouraging results in the prevention of this disease. The mechanism of anticancer effect is suggested partly through potentiation of bioactive compounds like vitamin E, phytic acid, γ-aminobutyric acid (GABA, γ-oryzanol, and phenolics. Nevertheless, the bioactivity of rice and its by-products is still incompletely understood. In this review, we present the findings from a preclinical study both in in vitro and in animal experiments on the promising role of rice by-products with focus on cancer prevention.

Cyclooxygenase-2 inhibitors in colorectal cancer prevention: point.

Science.gov (United States)

Arber, Nadir

2008-08-01

The limited success of current treatments for most advanced common malignancies highlights the importance of cancer prevention. Clinical trials on cyclooxygenase (COX) inhibitor drugs showed the potential of chemoprevention as a strategy for reducing cancer incidence, although not without associated side effects. The attractiveness of these drugs partly stems from an ability to engage multiple mechanisms of action by their potential to influence multiple components of the carcinogenesis pathway, from initiation to progression. There are two isoforms of the COX enzymes. COX-1 is constitutively expressed in normal tissues and serves as a "housekeeper" of mucosal integrity, whereas COX-2 is an immediate early response gene that is highly inducible by neoplastic and inflammatory stimuli. COX-2 is significantly overexpressed in colorectal neoplasms, making it an attractive therapeutic target. The drug market has been revolutionized by the development of preparations targeted selectively against COX-2, and a proof of concept has been achieved. Chemoprevention of colorectal cancer is already possible with celecoxib, but it is still not the ultimate drug of choice especially because of the cardiovascular risk associated with COX-2 inhibitors. Better patient selection and more effective and safer drugs are needed. Celecoxib is probably best used in a subset of individuals at moderate to high colorectal cancer risk and low risk of cardiovascular disease.

ent-Rosane and abietane diterpenoids as cancer chemopreventive agents.

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Núñez, Marvin J; Reyes, Carolina P; Jiménez, Ignacio A; Hayashi, Hirotaka; Tokuda, Harukuni; Bazzocchi, Isabel L

2011-04-01

Two ent-rosane- (cuzcol, 1 and 6-dehydroxycuzcol, 2) and a abietatriene- (salvadoriol, 3) type diterpenoids have been isolated from Maytenus cuzcoina and Crossopetalum uragoga, respectively, along with five known diterpene compounds (4-8). Their stereostructures have been elucidated on the basis of spectroscopic analysis, including 1D and 2D NMR techniques, and computational data. The absolute configuration of cuzcol was determined by application of Riguera ester procedure. This is the first instance of isolation of ent-rosane diterpenoids from species of the Celastraceae. The isolated diterpenes were found to be potent anti-tumour-promoter agents, and carnosol (7) also showed a remarkable chemopreventive effect in an in vivo two-stage carcinogenesis model. Copyright © 2011 Elsevier Ltd. All rights reserved.

Breast Cancer Chemoprevention: A Network Meta-Analysis of Randomized Controlled Trials.

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Mocellin, Simone; Pilati, Pierluigi; Briarava, Marta; Nitti, Donato

2016-02-01

Several agents have been advocated for breast cancer primary prevention. However, few of them appear effective, the associated severe adverse effects limiting their uptake. We performed a comprehensive search for randomized controlled trials (RCTs) reporting on the ability of chemoprevention agents (CPAs) to reduce the incidence of primary breast carcinoma. Using network meta-analysis, we ranked CPAs based simultaneously on efficacy and acceptability (an inverse measure of toxicity). All statistical tests were two-sided. We found 48 eligible RCTs, enrolling 271 161 women randomly assigned to receive either placebo or one of 21 CPAs. Aromatase inhibitors (anastrozole and exemestane, considered a single CPA class because of the lack of between-study heterogeneity; relative risk [RR] = 0.468, 95% confidence interval [CI] = 0.346 to 0.634), arzoxifene (RR = 0.415, 95% CI = 0.253 to 0.682), lasofoxifene (RR = 0.208, 95% CI = 0.079 to 0.544), raloxifene (RR = 0.572, 95% CI = 0.372 to 0.881), tamoxifen (RR = 0.708, 95% CI = 0.595 to 0.842), and tibolone (RR = 0.317, 95% CI = 0.127 to 0.792) were statistically significantly associated with a therapeutic effect, which was restricted to estrogen receptor-positive tumors of postmenopausal women (except for tamoxifen, which is active also during premenopause). Network meta-analysis ranking showed that the new selective estrogen receptor modulators (SERMs) arzoxifene, lasofoxifene, and raloxifene have the best benefit-risk ratio. Aromatase inhibitors and tamoxifen ranked second and third, respectively. These results provide physicians and health care regulatory agencies with RCT-based evidence on efficacy and acceptability of currently available breast cancer CPAs; at the same time, we pinpoint how much work still remains to be done before pharmacological primary prevention becomes a routine option to reduce the burden of this disease. © The Author 2015. Published by Oxford University Press. All rights reserved. For

Development of in vitro models for cellular and molecular studies in toxicology and chemoprevention

Energy Technology Data Exchange (ETDEWEB)

Mace, K.; Offord, E.A.; Harris, C.C.; Pfeifer, A.M.A. [Nestle Research Center, Lausanne (Switzerland)

1998-12-31

Many natural dietary phytochemicals found compounds found in fruits, vegetables, spices and tea have been shown in recent years to be protective against cancer in various animal models. In the light of the potential impact of these compounds on human health it is important to elucidate the mechanisms involved. We therefore developed and characterized relevant in vitro models using immortalized human epithelial cell lines derived from target tissues in carcinogenesis, such as lung, liver and colon. Assays were established, allowing the evaluation of the cytotoxic and genotoxic effects of various procarcinogens, including nitrosamines, mycotoxins and heterocyclic amines on these metabolically-competent human epithelial cell lines. These cellular models appeared to be a useful tool to study the capacity of certain food components to block the initiation stage of carcinogenesis. The ability of carnosol and carnosic acid from rosemary as well as the synthetic dithiolethione, oltipraz, to block the formation of DNA adducts, and their effects on the expression of phase I and phase II enzymes was investigated. We have observed that both rosemary extracts and oltiprax inhibited benzo(a)pyrene- or aflatoxin B{sub 1}-induced DNA adduct formation by strongly inhibiting CYP{sub 450} activities and inducing the expression of glutathione S-transferase. These results in human cell models give some insight into the different mechanisms involved in the chemopreventive action of both natural and synthetic compounds in relation to phase I and phase II enzymes. (orig.)

New perspectives of curcumin in cancer prevention

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Park, Wungki; Amin, A.R.M Ruhul; Chen, Zhuo Georgia; Shin, Dong M.

2013-01-01

Numerous natural compounds have been extensively investigated for their potential for cancer prevention over decades. Curcumin, from Curcuma longa, is a highly promising natural compound that can be potentially used for chemoprevention of multiple cancers. Curcumin modulates multiple molecular pathways involved in the lengthy carcinogenesis process to exert its chemopreventive effects through several mechanisms: promoting apoptosis, inhibiting survival signals, scavenging reactive oxidative species (ROS), and reducing the inflammatory cancer microenvironment. Curcumin fulfills the characteristics for an ideal chemopreventive agent with its low toxicity, affordability, and easy accessibility. Nevertheless, the clinical application of curcumin is currently compromised by its poor bioavailability. Here we review the potential of curcumin in cancer prevention, its molecular targets, and action mechanisms. Finally, we suggest specific recommendations to improve its efficacy and bioavailability for clinical applications. PMID:23466484

Zileuton, 5-lipoxygenase inhibitor, acts as a chemopreventive agent in intestinal polyposis, by modulating polyp and systemic inflammation.

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Elias Gounaris

Full Text Available Leukotrienes and prostaglandins, products of arachidonic acid metabolism, sustain both systemic and lesion-localized inflammation. Tumor-associated Inflammation can also contribute to the pathogenesis of colon cancer. Patients with inflammatory bowel disease (IBD have increased risk of developing colon cancer. The levels of 5-lipoxygenase (5-LO, the key enzyme for leukotrienes production, are increased in colon cancer specimens and colonic dysplastic lesions. Here we report that Zileuton, a specific 5-LO inhibitor, can prevent polyp formation by efficiently reducing the tumor-associated and systemic inflammation in APCΔ468 mice.In the current study, we inhibited 5-LO by dietary administration of Zileuton in the APCΔ468 mouse model of polyposis and analyzed the effect of in vivo 5-LO inhibition on tumor-associated and systemic inflammation.Zileuton-fed mice developed fewer polyps and displayed marked reduction in systemic and polyp-associated inflammation. Pro-inflammatory cytokines and pro-inflammatory innate and adaptive immunity cells were reduced both in the lesions and systemically. As part of tumor-associated inflammation Leukotriene B4 (LTB4, product of 5-LO activity, is increased focally in human dysplastic lesions. The 5-LO enzymatic activity was reduced in the serum of Zileuton treated polyposis mice.This study demonstrates that dietary administration of 5-LO specific inhibitor in the polyposis mouse model decreases polyp burden, and suggests that Zileuton may be a potential chemo-preventive agent in patients that are high-risk of developing colon cancer.

Potential targets for colorectal cancer prevention.

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Temraz, Sally; Mukherji, Deborah; Shamseddine, Ali

2013-08-22

The step-wise development of colorectal neoplasia from adenoma to carcinoma suggests that specific interventions could delay or prevent the development of invasive cancer. Several key factors involved in colorectal cancer pathogenesis have already been identified including cyclooxygenase 2 (COX-2), nuclear factor kappa B (NF-κB), survivin and insulin-like growth factor-I (IGF-I). Clinical trials of COX-2 inhibitors have provided the "proof of principle" that inhibition of this enzyme can prevent the formation of colonic adenomas and potentially carcinomas, however concerns regarding the potential toxicity of these drugs have limited their use as a chemopreventative strategy. Curcumin, resveratrol and quercetin are chemopreventive agents that are able to suppress multiple signaling pathways involved in carcinogenesis and hence are attractive candidates for further research.

Catalase, a remarkable enzyme: targeting the oldest antioxidant enzyme to find a new cancer treatment approach.

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Glorieux, Christophe; Calderon, Pedro Buc

2017-09-26

This review is centered on the antioxidant enzyme catalase and will present different aspects of this particular protein. Among them: historical discovery, biological functions, types of catalases and recent data with regard to molecular mechanisms regulating its expression. The main goal is to understand the biological consequences of chronic exposure of cells to hydrogen peroxide leading to cellular adaptation. Such issues are of the utmost importance with potential therapeutic extrapolation for various pathologies. Catalase is a key enzyme in the metabolism of H2O2 and reactive nitrogen species, and its expression and localization is markedly altered in tumors. The molecular mechanisms regulating the expression of catalase, the oldest known and first discovered antioxidant enzyme, are not completely elucidated. As cancer cells are characterized by an increased production of reactive oxygen species (ROS) and a rather altered expression of antioxidant enzymes, these characteristics represent an advantage in terms of cell proliferation. Meanwhile, they render cancer cells particularly sensitive to an oxidant insult. In this context, targeting the redox status of cancer cells by modulating catalase expression is emerging as a novel approach to potentiate chemotherapy.

Kaiware Daikon (Raphanus sativus L.) extract: a naturally multipotent chemopreventive agent.

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Barillari, Jessica; Iori, Renato; Papi, Alessio; Orlandi, Marina; Bartolini, Giovanna; Gabbanini, Simone; Pedulli, Gian Franco; Valgimigli, Luca

2008-09-10

Brassica vegetables are attracting major attention as healthy foods because of their content of glucosinolates (GLs) that release the corresponding isothiocyanates (ITCs) upon myrosinase hydrolysis. A number of studies have so far documented the chemopreventive properties of some ITCs. On the other hand, single nutrients detached from the food itself risk being somewhat "reductive", since plants contain several classes of compounds endowed with a polyhedral mechanism of action. Our recent finding that 4-methylthio-3-butenyl isothiocyanate (GRH-ITC) and 4-methylsulfinyl-3-butenyl isothiocyanate (GRE-ITC), released by the GLs purified from Japanese (Kaiware) Daikon (Raphanus sativus L.) seeds and sprouts, had selective cytotoxic/apoptotic activity on three human colon carcinoma cell lines prompted further research on the potential chemopreventive role of a standardized Kaiware Daikon extract (KDE), containing 10.5% w/w GRH and 3.8% w/w GRE, compared to its isolated components. KDE administered in combination with myrosinase at doses corresponding to 50 microM GRH-ITC plus 15 microM GRE-ITC (50 microM KDE-ITC) to three human cancer cell lines (LoVo, HCT-116 and HT-29) significantly reduced cell growth by 94-96% of control in six days (p oxygen consumption rate), as monitored by Clark-type microelectrode oxygen-uptake kinetics, and induced very fast quenching of DPPH. radical in methanol with t(1/2) (s) = (1.47 +/- 0.25) x 10(-2)/[KDE; (g/L)], measured by stopped-flow UV-vis kinetics at 298 K. The potential chemopreventive role of KDE is discussed.

Serum levels of polyamine synthesis enzymes increase in diabetic patients with breast cancer

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V Kenan Çelik

2017-09-01

Full Text Available In this study, it was aimed to investigate the relationship between diabetes and breast cancer and the detection of enzymes and ornithine levels in polyamine synthesis pathway in diabetes, breast cancer and diabetic breast cancer patients. Methods: Ornithine, arginine decarboxylase, ornithine decarboxylase and agmatinase levels have been measured in serum of all groups. Ornithine levels were measured spectrophotometrically. Arginine decarboxylase, ornithine decarboxylase and agmatinase levels were determined by ELISA kits. Results: Except for the diabetic group, the levels of enzymes in the polyamine synthesis pathway were increased in all and statistically significant (P < 0.05. The increase in the levels of agmatinase was very important among the enzymes (P < 0.001. Conclusions: Decreased levels of polyamine synthase enzymes in diabetes mellitus were found to be increased patients with breast cancer. Whether and how diabetes-based breast cancer development relates to increase activity of enzymes responsible for polyamine synthesis requires further mechanistic and prospective monitoring studies in larger patient cohorts.

Impact of nanotechnology on the delivery of natural products for cancer prevention and therapy.

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Siddiqui, Imtiaz A; Sanna, Vanna

2016-06-01

Chemoprevention of human cancer by dietary products is a practical approach of cancer control, especially when chemoprevention is involved during the early stages of the carcinogenesis process. Research over the last few decades has clearly demonstrated the efficacy of dietary products for chemoprevention in cell culture and preclinical animal model systems. However, these in vitro and in vivo effects have not been able to be translated to bedside for clinical use. Among many reasons, inefficient systemic delivery and bioavailability of promising chemopreventive agents are considered to significantly contribute to such a disconnection. Since its advent in the field of cancer, nanotechnology has provided researchers with expertise to explore new avenues for diagnosis, prevention, and therapy of the disease. In a similar trait, we introduced a novel concept in which nanotechnology was utilized for enhancing the outcome of chemoprevention (Cancer Res. 2009; 69:1712-1716). This idea, which we termed as 'nanochemoprevention', was exploited by several laboratories and has now become an advancing field in chemoprevention research. This review summarizes some of these applications of nanotechnology in medicine, particularly focused on controlled and sustained release of bioactive compounds with emphasis on current and future utilization of nanochemoprevention for prevention and therapy of cancer. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chemopreventive properties of curcumin analogues ...

African Journals Online (AJOL)

Chemopreventive properties of curcumin analogues, ... These compounds .... using microscope with 400 × magnification. APC ... Figure 3: Microscopic images of rat colorectal tissue stained with APC rabbit polyclonal antibody with different.

Red Wine Polyphenols for Cancer Prevention

Science.gov (United States)

He, Shan; Sun, Cuirong; Pan, Yuanjiang

2008-01-01

Conventional cancer therapies, the second leading cause of death worldwide, result in serious side effects and, at best, merely extend the patient's lifespan by a few years. Searching for effective prevention is of high priority in both basic and clinical sciences. In recent decades natural products have been considered to be an important source of cancer chemopreventive agents. Red wine polyphenols, which consisted of various powerful antioxidants such as flavonoids and stilbenes, have been implicated in cancer prevention and that promote human health without recognizable side effects. Since resveratrol, a major component of red wine polyphenols, has been studied and reviewed extensively for its chemopreventive activity to interfere with the multi-stage carcinogenesis, this review focuses on recent progress in studies on cancer chemopreventive activities of red wine polyphenol extracts and fractions as well as other red wine polyphenols, like procyanidin B5 analogues and myricetin. PMID:19325788

Red Wine Polyphenols for Cancer Prevention

Directory of Open Access Journals (Sweden)

Yuanjiang Pan

2008-05-01

Full Text Available Conventional cancer therapies, the second leading cause of death worldwide, result in serious side effects and, at best, merely extend the patient's lifespan by a few years. Searching for effective prevention is of high priority in both basic and clinical sciences. In recent decades natural products have been considered to be an important source of cancer chemopreventive agents. Red wine polyphenols, which consisted of various powerful antioxidants such as flavonoids and stilbenes, have been implicated in cancer prevention and that promote human health without recognizable side effects. Since resveratrol, a major component of red wine polyphenols, has been studied and reviewed extensively for its chemopreventive activity to interfere with the multi-stage carcinogenesis, this review focuses on recent progress in studies on cancer chemopreventive activities of red wine polyphenol extracts and fractions as well as other red wine polyphenols, like procyanidin B5 analogues and myricetin.

Dietary Bioactive Diallyl Trisulfide in Cancer Prevention and Treatment.

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Puccinelli, Michael T; Stan, Silvia D

2017-07-28

Bioactive dietary agents have been shown to regulate multiple cancer hallmark pathways. Epidemiologic studies have linked consumption of Allium vegetables, such as garlic and onions, to decreased incidence of cancer. Diallyl trisulfide (DATS), a bioactive compound derived from Allium vegetables, has been investigated as an anti-cancer and chemopreventive agent. Preclinical studies provide ample evidence that DATS regulates multiple cancer hallmark pathways including cell cycle, apoptosis, angiogenesis, invasion, and metastasis. DATS has been shown to arrest cancer cells at multiple stages of the cell cycle with the G2/M arrest being the most widely reported. Additionally, increased pro-apoptotic capacity as a result of regulating intrinsic and extrinsic apoptotic pathway components has been widely reported following DATS treatment. Invasion, migration, and angiogenesis represent emerging targets of DATS and support its anti-cancer properties. This review summarizes DATS mechanisms of action as an anti-cancer and chemopreventive agent. These studies provide rationale for future investigation into its use as a cancer chemopreventive agent.

Chemopreventive effect of myrtenal on bacterial enzyme activity and the development of 1,2-dimethyl hydrazine-induced aberrant crypt foci in Wistar Rats

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Lokesh Kumar Booupathy

2016-01-01

Full Text Available Colon cancer remains as a serious health problem around the world despite advances in diagnosis and treatment. Dietary fibers are considered to reduce the risk of colon cancer as they are converted to short chain fatty acids by the presence of anaerobic bacteria in the intestine, but imbalanced diet and high fat consumption may promote tumor formation at different sites, including the large bowel via increased bacterial enzymes activity. The present study was conducted to characterize the inhibitory action of myrtenal on bacterial enzymes and aberrant crypt foci (ACF. Experimental colon carcinogenesis induced by 1,2-dimethylhydrazine is histologically, morphologically, and anatomically similar to human colonic epithelial neoplasm. Discrete microscopic mucosal lesions such as ACF and malignant tumors function as important biomarkers in the diagnosis of colon cancer. Methylene blue staining was carried out to visualize the impact of 1,2-dimethylhydrazine and myrtenal. Myrtenal-treated animals showed decreased levels of bacterial enzymes such as β-glucuronidase, β-glucosidase, and mucinase. Characteristic changes in the colon were noticed by inhibiting ACF formation in the colon. In conclusion, treatment with myrtenal provided altered pathophysiological condition in colon cancer-bearing animals with evidence of decreased crypt multiplicity and tumor progression.

Phase 0 Clinical Chemoprevention Trial of the AKT Inhibitor SR13668

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Reid, Joel M.; Walden, Chad; Qin, Rui; Allen Ziegler, Katie L.; Haslam, John L.; Rajewski, Roger A.; Warndahl, Roger; Fitting, Cindy L.; Boring, Daniel; Szabo, Eva; Crowell, James; Perloff, Marjorie; Jong, Ling; Mandrekar, Sumithra J.; Ames, Matthew M.; Limburg, Paul J.

2011-01-01

Purpose SR13668, an orally active AKT pathway inhibitor, has demonstrated cancer chemopreventive potential in preclinical studies. To accelerate the clinical development of this promising agent, we designed and conducted the first-ever phase 0 chemoprevention trial to evaluate and compare the effects of food and formulation on SR13668 bioavailability. Patients and Methods Healthy adult volunteers were randomly assigned to receive a single, 38 mg oral dose of SR13668 in one of five different formulations, with or without food. Based on existing animal data, SR13668 in a PEG400/Labrasol® oral solution was defined as the reference formulation. Blood samples were obtained pre- and post-agent administration for pharmacokinetic analyses. Area under the plasma concentration-time curve (AUC0-∞) was defined as the primary endpoint. Data were analyzed and compared using established statistical methods for phase 0 trials with a limited sample size. Results Participants (N=20) were rapidly accrued over a 5-month period. Complete pharmacokinetic data were available for 18 randomized participants. AUC0-∞ values were highest in the fed state (range = 122–439 ng/mL × hours) and were statistically significantly different across formulations (p = 0.007), with Solutol® HS15 providing the highest bioavailability. SR13668 time to peak plasma concentration (3 hours; range, 2 – 6 hours) and half-life were (11.2 ± 3.1 hours) were not formulation dependent. Conclusions Using a novel, highly efficient study design, we rapidly identified a lead formulation of SR13668 for further clinical testing. Our findings support application of the phase 0 trial paradigm to accelerate chemoprevention agent development. PMID:21372034

Potential Targets for Colorectal Cancer Prevention

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Ali Shamseddine

2013-08-01

Full Text Available The step-wise development of colorectal neoplasia from adenoma to carcinoma suggests that specific interventions could delay or prevent the development of invasive cancer. Several key factors involved in colorectal cancer pathogenesis have already been identified including cyclooxygenase 2 (COX-2, nuclear factor kappa B (NF-κB, survivin and insulin-like growth factor-I (IGF-I. Clinical trials of COX-2 inhibitors have provided the “proof of principle” that inhibition of this enzyme can prevent the formation of colonic adenomas and potentially carcinomas, however concerns regarding the potential toxicity of these drugs have limited their use as a chemopreventative strategy. Curcumin, resveratrol and quercetin are chemopreventive agents that are able to suppress multiple signaling pathways involved in carcinogenesis and hence are attractive candidates for further research.

Beyond COX-1: the effects of aspirin on platelet biology and potential mechanisms of chemoprevention.

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Ornelas, Argentina; Zacharias-Millward, Niki; Menter, David G; Davis, Jennifer S; Lichtenberger, Lenard; Hawke, David; Hawk, Ernest; Vilar, Eduardo; Bhattacharya, Pratip; Millward, Steven

2017-06-01

After more than a century, aspirin remains one of the most commonly used drugs in western medicine. Although mainly used for its anti-thrombotic, anti-pyretic, and analgesic properties, a multitude of clinical studies have provided convincing evidence that regular, low-dose aspirin use dramatically lowers the risk of cancer. These observations coincide with recent studies showing a functional relationship between platelets and tumors, suggesting that aspirin's chemopreventive properties may result, in part, from direct modulation of platelet biology and biochemistry. Here, we present a review of the biochemistry and pharmacology of aspirin with particular emphasis on its cyclooxygenase-dependent and cyclooxygenase-independent effects in platelets. We also correlate the results of proteomic-based studies of aspirin acetylation in eukaryotic cells with recent developments in platelet proteomics to identify non-cyclooxygenase targets of aspirin-mediated acetylation in platelets that may play a role in its chemopreventive mechanism.

Selenium Supranutrition: Are the Potential Benefits of Chemoprevention Outweighed by the Promotion of Diabetes and Insulin Resistance?

Science.gov (United States)

Rocourt, Caroline R. B.; Cheng, Wen-Hsing

2013-01-01

Selenium was considered a toxin until 1957, when this mineral was shown to be essential in the prevention of necrotic liver damage in rats. The hypothesis of selenium chemoprevention is principally formulated by the observations that cancer incidence is inversely associated with selenium status. However, recent clinical and epidemiological studies demonstrate a role for some selenoproteins in exacerbating or promoting other disease states, specifically type 2 diabetes, although other data support a role of selenium in stimulating insulin sensitivity. Therefore, it is clear that our understanding in the role of selenium in glucose metabolism and chemoprevention is inadequate and incomplete. Research exploring the role of selenium in individual healthcare is of upmost importance and possibly will help explain how selenium is a double-edged sword in the pathologies of chronic diseases. PMID:23603996

Polyethylene Glycol Mediated Colorectal Cancer Chemoprevention: Roles of Epidermal Growth Factor Receptor and Snail

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Wali, Ramesh K.; Kunte, Dhananjay P.; Koetsier, Jennifer L.; Bissonnette, Marc; Roy, Hemant K.

2008-01-01

Polyethylene glycol (PEG) is a clinically widely used agent with profound chemopreventive properties in experimental colon carcinogenesis. We previously reported that Snail/β-catenin signaling may mediate the suppression of epithelial proliferation by PEG, although the upstream events remain unclear. We report herein the role of epidermal growth factor receptor (EGFR), a known mediator of Snail and overepressed in ~80% of human colorectal cancers (CRC), on PEG-mediated anti-proliferative and hence anti-neoplastic effects in azoxymethane (AOM)-rats and HT-29 colon cancer cells. AOM-rats were randomized to either standard diet or one with 10% PEG 3350 and euthanized 8 weeks later. The colonic samples were subjected to immunohistochemical or Western blot analyses. PEG decreased mucosal EGFR by 60% (pPEG effects were obtained in HT-29 cells. PEG suppressed EGFR protein via lysosmal degradation with no change in mRNA levels. To show that EGFR antagonism per se was responsible for the antiproliferative effect, we inhibited EGFR by either pre-treating cells with gefitinib or stably transfecting with EGFR-shRNA and measured the effect of PEG on proliferation. In either case PEG effect was blunted suggesting a vital role of EGFR. Flow cytometric analysis revealed that EGFR-shRNA cells, besides having reduced membrane EGFR also expressed low Snail levels (40%), corroborating a strong association. Furthermore, in EGFR silenced cells PEG effect on EGFR or Snail was muted, similar to that on proliferation. In conclusion, we show that EGFR is the proximate membrane signaling molecule through which PEG initiates antiproliferative activity with Snail/β-catenin pathway playing the central intermediary function. PMID:18790788

Polyethylene glycol-mediated colorectal cancer chemoprevention: roles of epidermal growth factor receptor and Snail.

Science.gov (United States)

Wali, Ramesh K; Kunte, Dhananjay P; Koetsier, Jennifer L; Bissonnette, Marc; Roy, Hemant K

2008-09-01

Polyethylene glycol (PEG) is a clinically widely used agent with profound chemopreventive properties in experimental colon carcinogenesis. We reported previously that Snail/beta-catenin signaling may mediate the suppression of epithelial proliferation by PEG, although the upstream events remain unclear. We report herein the role of epidermal growth factor receptor (EGFR), a known mediator of Snail and overexpressed in approximately 80% of human colorectal cancers, on PEG-mediated antiproliferative and hence antineoplastic effects in azoxymethane (AOM) rats and HT-29 colon cancer cells. AOM rats were randomized to either standard diet or one with 10% PEG-3350 and euthanized 8 weeks later. The colonic samples were subjected to immunohistochemical or Western blot analyses. PEG decreased mucosal EGFR by 60% (P PEG effects were obtained in HT-29 cells. PEG suppressed EGFR protein via lysosmal degradation with no change in mRNA levels. To show that EGFR antagonism per se was responsible for the antiproliferative effect, we inhibited EGFR by either pretreating cells with gefitinib or stably transfecting with EGFR-short hairpin RNA and measured the effect of PEG on proliferation. In either case, PEG effect was blunted, suggesting a vital role of EGFR. Flow cytometric analysis revealed that EGFR-short hairpin RNA cells, besides having reduced membrane EGFR, also expressed low Snail levels (40%), corroborating a strong association. Furthermore, in EGFR silenced cells, PEG effect on EGFR or Snail was muted, similar to that on proliferation. In conclusion, we show that EGFR is the proximate membrane signaling molecule through which PEG initiates antiproliferative activity with Snail/beta-catenin pathway playing the central intermediary function.

MRI to assess chemoprevention in transgenic adenocarcinoma of mouse prostate (TRAMP)

International Nuclear Information System (INIS)

Arbab, Ali S; Shankar, Adarsh; Varma, Nadimpalli RS; Deeb, Dorrah; Gao, Xiaohua; Iskander, ASM; Janic, Branislava; Ali, Meser M; Gautam, Subhash C

2011-01-01

indicating higher number of tumor foci, which was also proven by histology. In vivo MRI is helpful in determining the efficacy of chemoprevention of prostate cancer in TRAMP mice

A randomized phase II chemoprevention trial of 13-CIS retinoic acid with or without alpha tocopherol or observation in subjects at high risk for lung cancer.

Science.gov (United States)

Kelly, Karen; Kittelson, John; Franklin, Wilbur A; Kennedy, Timothy C; Klein, Catherine E; Keith, Robert L; Dempsey, Edward C; Lewis, Marina; Jackson, Mary K; Hirsch, Fred R; Bunn, Paul A; Miller, York E

2009-05-01

No chemoprevention strategies have been proven effective for lung cancer. We evaluated the effect of 13-cis retinoic acid (13-cis RA), with or without alpha tocopherol, as a lung cancer chemoprevention agent in a phase II randomized controlled clinical trial of adult subjects at high risk for lung cancer as defined by the presence of sputum atypia, history of smoking, and airflow obstruction, or a prior surgically cured nonsmall cell lung cancer (disease free, >3 years). Subjects were randomly assigned to receive either 13-cis RA, 13-cis RA plus alpha tocopherol (13-cis RA/alpha toco) or observation for 12 months. Outcome measures are derived from histologic evaluation of bronchial biopsy specimens obtained by bronchoscopy at baseline and follow-up. The primary outcome measure is treatment "failure" defined as histologic progression (any increase in the maximum histologic score) or failure to return for follow-up bronchoscopy. Seventy-five subjects were randomized (27/22/26 to observations/13-cis RA/13-cis RA/alpha toco); 59 completed the trial; 55 had both baseline and follow-up bronchoscopy. The risk of treatment failure was 55.6% (15 of 27) and 50% (24 of 48) in the observation and combined (13 cis RA plus 13 cis RA/alpha toco) treatment arms, respectively (odds ratio adjusted for baseline histology, 0.97; 95% confidence interval, 0.36-2.66; P = 0.95). Among subjects with complete histology data, maximum histology score in the observation arm increased by 0.37 units and by 0.03 units in the treated arms (difference adjusted for baseline, -0.18; 95% confidence interval, -1.16 to 0.81; P = 0.72). Similar (nonsignificant) results were observed for treatment effects on endobronchial proliferation as assessed by Ki-67 immunolabeling. Twelve-month treatment with 13-cis RA produced nonsignificant changes in bronchial histology, consistent with results in other trials. Agents advancing to phase III randomized trials should produce greater histologic changes. The

A Randomized Phase II Chemoprevention Trial of 13-CIS Retinoic Acid with Or without α Tocopherol or Observation in Subjects at High Risk for Lung Cancer

Science.gov (United States)

Kelly, Karen; Kittelson, John; Franklin, Wilbur A.; Kennedy, Timothy C.; Klein, Catherine E.; Keith, Robert L.; Dempsey, Edward C.; Lewis, Marina; Jackson, Mary K.; Hirsch, Fred R.; Bunn, Paul A.; Miller, York E.

2011-01-01

No chemoprevention strategies have been proven effective for lung cancer. We evaluated the effect of 13-cis retinoic acid (13-cis RA), with or without α tocopherol, as a lung cancer chemoprevention agent in a phase II randomized controlled clinical trial of adult subjects at high risk for lung cancer as defined by the presence of sputum atypia, history of smoking, and airflow obstruction, or a prior surgically cured nonsmall cell lung cancer (disease free, >3 years). Subjects were randomly assigned to receive either 13-cis RA, 13-cis RA plus α tocopherol (13-cis RA/α toco) or observation for 12 months. Outcome measures are derived from histologic evaluation of bronchial biopsy specimens obtained by bronchoscopy at baseline and follow-up. The primary outcome measure is treatment “failure” defined as histologic progression (any increase in the maximum histologic score) or failure to return for follow-up bronchoscopy. Seventy-five subjects were randomized (27/22/26 to obervations/13-cis RA/13-cis RA/α toco); 59 completed the trial; 55 had both baseline and follow-up bronchoscopy. The risk of treatment failure was 55.6% (15 of 27) and 50% (24 of 48) in the observation and combined (13 cis RA plus 13 cis RA/α toco) treatment arms, respectively (odds ratio adjusted for baseline histology, 0.97; 95% confidence interval, 0.36–2.66; P = 0.95). Among subjects with complete histology data, maximum histology score in the observation arm increased by 0.37 units and by 0.03 units in the treated arms (difference adjusted for baseline, −0.18; 95% confidence interval, −1.16 to 0.81; P = 0.72). Similar (nonsignificant) results were observed for treatment effects on endobronchial proliferation as assessed by Ki-67 immunolabeling. Twelve-month treatment with 13-cis RA produced nonsignificant changes in bronchial histology, consistent with results in other trials. Agents advancing to phase III randomized trials should produce greater histologic changes. The addition of �

Radioisotope-enzymes and cancer study

International Nuclear Information System (INIS)

Luyen, T. van

2008-01-01

Cancer is a pathological sign, when the abnormal cells appear in certain human tissues or organs. These cells can reproduce beyond the control of normal biological protection mechanism. Because they reproduce very fast, the metabolic process is accelerated, which causes the extreme need for more energy, substrate and catalyzing enzymes. Based on these needs, we can control the metabolic process by: Stopping supplying the energy. Stopping supplying the substrate and the materials to build up the cell's structure. Stopping operating catalysis by breaking out the enzyme's structure. Destroying the tumor cell by extra agents such as radiations and chemicals. All of these methods have been studied for a long time, which costs too much money, time and labor. Although we succeeded in some ways, the results are still not satisfactory. There are many reasons for this situation but the main one is the lack of information to understand all the processes taking place in the cell and our body. However, as far as we studied, we would like to propose the method to break the structure of the enzyme by nuclear decay process. (author)

Burden and Chemoprevention of Skin Cancer

NARCIS (Netherlands)

L.M. Hollestein (Loes)

2013-01-01

markdownabstractThe incidence of skin cancer is increasing in the Netherlands since 1989, the first year of the Netherlands Cancer Registry (NCR). In 2010 more than 43,000 patients were newly diagnosed with skin cancer in the Netherlands. During a life time at least 1 in 5 persons living in

Chemopreventive Effect of Aster glehni on Inflammation-Induced Colorectal Carcinogenesis in Mice

Directory of Open Access Journals (Sweden)

Kyung-Sook Chung

2018-02-01

Full Text Available Although Aster glehni is a common dietary herb that has various bioactivities, including anti-diabetic, anti-adipogenic, and anti-inflammatory effects, A. glehni has not been studied in colon cancer. Therefore, we hypothesized the chemopreventive effects of an ethanol extract of A. glehni (AG on azoxymethane/dextran sulfate sodium (AOM/DSS-induced colitis-associated cancer (CAC in mice. In this study, we found that treatment with AG significantly attenuated the AOM/DSS-induced enlargement of the spleen and shortening of the colon. In addition, colonic tumor formation, colonic damage, and increased muscle thickness were significantly reduced in AOM/DSS-induced mice fed AG. Treatment with AG also reduced intestinal interleukin (IL-1β, IL-6, and tumor necrosis factor (TNF-α production and decreased inducible nitric oxide synthase (iNOS and cyclooxygenase (COX-2 protein expression in mice with AOM/DSS-induced CAC. Furthermore, AG reduced nuclear factor (NF-κB activation via phosphorylation and degradation of inhibitor of kappa Bα (IκBα, leading to inhibition of NF-κB p65 nuclear translocation. It also downregulated the expression of NF-κB-related proteins, including the B-cell lymphoma 2 (Bcl-2 family and inhibitors of apoptosis proteins (IAPs, in mice with AOM/DSS-induced CAC. Taken together, these findings suggest that the treatment with AG inhibited colitis-associated colon carcinogenesis in mice, and this chemopreventive effect was strongly mediated by suppression of the NF-κB signaling pathway, indicating that AG could be a promising protective agent against CAC.

Trimethoxy-resveratrol and piceatannol administered orally suppress and inhibit tumor formation and growth in prostate cancer xenografts

Science.gov (United States)

Resveratrol (Res) is recognized as a promising cancer chemoprevention dietary polyphenol with antioxidative, anti-inflammatory and anticancer properties. However, the role of its analogues in prostate cancer (PCa) chemoprevention is still unknown. METHODS. We synthesized natural and synthetic anal...

Upregulation of intrinsic apoptotic pathway in NSAIDs mediated chemoprevention of experimental lung carcinogenesis.

Science.gov (United States)

Setia, Shruti; Sanyal, Sankar N

2012-01-01

Non-steroidal anti-inflammatory drugs (NSAIDs) act by inhibition of cyclooxygenase-2 (COX-2), which is overexpressed in cancer. The role of COX-2 and apoptosis were evaluated in 9,10-dimethylbenz(a)anthracene (DMBA)-induced lung cancer in rat and chemoprevention with indomethacin, a traditional NSAID and etoricoxib, a selective COX-2 inhibitor. The animals were divided into Control, DMBA, DMBA+ indomethacin and DMBA+ etoricoxib groups. They received a single intratracheal instillation of DMBA while NSAIDs were given orally daily for 32 weeks. Besides morphology and histology of lungs, RT-PCR, western blots and immunohistochemistry were performed for the expression of apoptotic proteins and COX enzymes. Apoptosis was studied by DNA fragmentation and fluorescent staining. The occurrence of tumors and lesions was noted in the DMBA animals, besides constricted alveolar spaces and hyperplasia. COX-1 was found to be uniformly expressed while COX-2 level was raised significantly in DMBA group. The apoptotic proteins, apaf-1, caspase-9 and caspase-3 were highly diminished in DMBA group but restored to normal level in NSAIDs groups. Also, apoptosis was suppressed in carcinogen group by DNA fragmentation analysis and fluorescent staining of the lung cells while co-administration of NSAIDs along with DMBA led to the restoration of apoptosis. DMBA administration to the rats led to tumorigenesis in the lungs, had no effects on COX-1 expression, while elevating the COX-2 levels and suppressing apoptosis. The treatment with NSAIDs led to the amelioration of these effects. However, etoricoxib which is a COX-2 specific inhibitor, was found to be more effective than the traditional NSAID, indomethacin.

Antioxidant enzyme expression and reactive oxygen species damage in prostatic intraepithelial neoplasia and cancer.

Science.gov (United States)

Bostwick, D G; Alexander, E E; Singh, R; Shan, A; Qian, J; Santella, R M; Oberley, L W; Yan, T; Zhong, W; Jiang, X; Oberley, T D

2000-07-01

Oxidative stress results in damage to cellular structures and has been linked to many diseases, including cancer. The authors sought to determine whether the expression of three major antioxidant enzymes, copper-zinc superoxide dismutase (SOD1), manganese superoxide dismutase (SOD2), and catalase, was altered in human prostate carcinoma and its likely precursor, high grade prostatic intraepithelial neoplasia (PIN). The level of reactive oxygen species damage was evaluated by measuring the expression of the DNA adduct 8-hydroxydeoxyguanosine. The authors evaluated the tissue expression of the antioxidant enzymes in prostate carcinoma by immunohistochemistry, immunogold electron microscopy, and enzymatic assay. The polymerase chain reaction was used to amplify and screen tissue specimens for the genes of SOD1, SOD2, and extracellular SOD (SOD3). Matched paraffin embedded tissue sections were evaluated by RNA in situ hybridization for expression of SOD1 and immunohistochemically for the DNA adduct 8-hydroxydeoxyguanosine. All prostatic tissues, including cancer, displayed immunoreactivity for the three antioxidant enzymes in epithelial cells, with no staining of the stroma, inflammatory cells, or endothelial cells. The number of immunoreactive cells was greater in benign epithelium than in PIN and cancer for each enzyme. The mean percentage and intensity of immunoreactive cells was greatest for SOD2, intermediate for SOD1, and lower for catalase. Staining in cancer was heterogeneous. Immunogold ultrasound studies revealed strong mitochondrial labeling for SOD2, which was greater in benign epithelium than in cancer; SOD1 labeling was invariably weaker, with nuclear labeling in benign epithelium and cytoplasmic labeling in cancer cells. There was no difference in enzyme activity for the three antioxidant enzymes between benign epithelium and cancer. No mutations were found in the 5 exons of SOD1, 5 exons of SOD2, and 3 exons of SOD3, except for 3 of 20 cases with

Sulforaphane, a cancer chemopreventive agent, induces pathways associated with membrane biosynthesis in response to tissue damage by aflatoxin B{sub 1}

Energy Technology Data Exchange (ETDEWEB)

Techapiesancharoenkij, Nirachara [Laboratory of Environmental Toxicology, Chulabhorn Research Institute, Bangkok 10210 (Thailand); Fiala, Jeannette L.A. [Department of Biological Engineering and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Navasumrit, Panida [Laboratory of Environmental Toxicology, Chulabhorn Research Institute, Bangkok 10210 (Thailand); Croy, Robert G.; Wogan, Gerald N. [Department of Biological Engineering and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Groopman, John D. [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205 (United States); Ruchirawat, Mathuros [Laboratory of Environmental Toxicology, Chulabhorn Research Institute, Bangkok 10210 (Thailand); Essigmann, John M., E-mail: jessig@mit.edu [Department of Biological Engineering and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

2015-01-01

Aflatoxin B{sub 1} (AFB{sub 1}) is one of the major risk factors for liver cancer globally. A recent study showed that sulforaphane (SF), a potent inducer of phase II enzymes that occurs naturally in widely consumed vegetables, effectively induces hepatic glutathione S-transferases (GSTs) and reduces levels of hepatic AFB{sub 1}-DNA adducts in AFB{sub 1}-exposed Sprague Dawley rats. The present study characterized the effects of SF pre-treatment on global gene expression in the livers of similarly treated male rats. Combined treatment with AFB{sub 1} and SF caused reprogramming of a network of genes involved in signal transduction and transcription. Changes in gene regulation were observable 4 h after AFB{sub 1} administration in SF-pretreated animals and may reflect regeneration of cells in the wake of AFB{sub 1}-induced hepatotoxicity. At 24 h after AFB{sub 1} administration, significant induction of genes that play roles in cellular lipid metabolism and acetyl-CoA biosynthesis was detected in SF-pretreated AFB{sub 1}-dosed rats. Induction of this group of genes may indicate a metabolic shift toward glycolysis and fatty acid synthesis to generate and maintain pools of intermediate molecules required for tissue repair, cell growth and compensatory hepatic cell proliferation. Collectively, gene expression data from this study provide insights into molecular mechanisms underlying the protective effects of SF against AFB{sub 1} hepatotoxicity and hepatocarcinogenicity, in addition to the chemopreventive activity of this compound as a GST inducer. - Highlights: • This study revealed sulforaphane (SF)-deregulated gene sets in aflatoxin B{sub 1} (AFB{sub 1})-treated rat livers. • SF redirects biochemical networks toward lipid biosynthesis in AFB{sub 1}-dosed rats. • SF enhanced gene sets that would be expected to favor cell repair and regeneration.

The Chemopreventive Phytochemical Moringin Isolated from Moringa oleifera Seeds Inhibits JAK/STAT Signaling.

Directory of Open Access Journals (Sweden)

Carina Michl

Full Text Available Sulforaphane (SFN and moringin (GMG-ITC are edible isothiocyanates present as glucosinolate precursors in cruciferous vegetables and in the plant Moringa oleifera respectively, and recognized for their chemopreventive and medicinal properties. In contrast to the well-studied SFN, little is known about the molecular pathways targeted by GMG-ITC. We investigated the ability of GMG-ITC to inhibit essential signaling pathways that are frequently upregulated in cancer and immune disorders, such as JAK/STAT and NF-κB. We report for the first time that, similarly to SFN, GMG-ITC in the nanomolar range suppresses IL-3-induced expression of STAT5 target genes. GMG-ITC, like SFN, does not inhibit STAT5 phosphorylation, suggesting a downstream inhibitory event. Interestingly, treatment with GMG-ITC or SFN had a limited inhibitory effect on IFNα-induced STAT1 and STAT2 activity, indicating that both isothiocyanates differentially target JAK/STAT signaling pathways. Furthermore, we showed that GMG-ITC in the micromolar range is a more potent inhibitor of TNF-induced NF-κB activity than SFN. Finally, using a cellular system mimicking constitutive active STAT5-induced cell transformation, we demonstrated that SFN can reverse the survival and growth advantage mediated by oncogenic STAT5 and triggers cell death, therefore providing experimental evidence of a cancer chemopreventive activity of SFN. This work thus identified STAT5, and to a lesser extent STAT1/STAT2, as novel targets of moringin. It also contributes to a better understanding of the biological activities of the dietary isothiocyanates GMG-ITC and SFN and further supports their apparent beneficial role in the prevention of chronic illnesses such as cancer, inflammatory diseases and immune disorders.

Nrf2: bane or blessing in cancer?

Science.gov (United States)

Xiang, MingJun; Namani, Akhileshwar; Wu, ShiJun; Wang, XiaoLi

2014-08-01

The Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor-E2-related factor 2 (Nrf2)-antioxidant response element pathway serves a major function in endogenous cytoprotection in normal cells. Nrf2 is a transcription factor that mainly regulates the expression of a wide array of genes that produce the antioxidants and other proteins responsible for the detoxification of xenobiotics and reactive oxygen species. Nrf2 mediates the chemoprevention of cancer in normal cells. Growing body of evidence suggests that Nrf2 is not only involved in the chemoprevention of normal cells but also promotes the growth of cancer cells. However, the mechanism underlying the function of Nrf2 in oncogenesis and tumor protection in cancer cells remains unclear and thus requires further study. This review aims to rationalize the existing functions of Nrf2 in chemoprevention and tumorigenesis, as well as the somatic mutations of Nrf2 and Keap1 in cancer and Nrf2 cross talk with miRNAs. This review also discusses the future challenges in Nrf2 research.

Pancreatic Enzymes

Science.gov (United States)

... Contact Us DONATE NOW GENERAL DONATION PURPLESTRIDE Pancreatic enzymes Home Facing Pancreatic Cancer Living with Pancreatic Cancer ... and see a registered dietitian. What are pancreatic enzymes? Pancreatic enzymes help break down fats, proteins and ...

Chemoprevention of Skin Cancer Program Project | Division of Cancer Prevention

Science.gov (United States)

DESCRIPTION (provided by applicant): Skin cancer is the most common malignancy in the world. One out of three new cancers is a skin cancer. More than 1 million cases of non-melanoma skin cancer (NMSC) (basal cell carcinoma [BCC] and squamous cell cancers [SCC]) occur annually. While the incidence rates for non-melanoma skin cancers continue to rise, there continues to be a

Inhibition of Akt enhances the chemopreventive effects of topical rapamycin in mouse skin

Science.gov (United States)

Dickinson, Sally E; Janda, Jaroslav; Criswell, Jane; Blohm-Mangone, Karen; Olson, Erik R.; Liu, Zhonglin; Barber, Christie; Rusche, Jadrian J.; Petricoin, Emmanuel; Calvert, Valerie; Einspahr, Janine G.; Dickinson, Jesse; Stratton, Steven P.; Curiel-Lewandrowski, Clara; Saboda, Kathylynn; Hu, Chengcheng; Bode, Ann M.; Dong, Zigang; Alberts, David S.; Bowden, G. Timothy

2016-01-01

The PI3Kinase/Akt/mTOR pathway has important roles in cancer development for multiple tumor types, including UV-induced non-melanoma skin cancer. Immunosuppressed populations are at increased risk of aggressive cutaneous squamous cell carcinoma (SCC). Individuals who are treated with rapamycin, (sirolimus, a classical mTOR inhibitor) have significantly decreased rates of developing new cutaneous SCCs compared to those that receive traditional immunosuppression. However, systemic rapamycin use can lead to significant adverse events. Here we explored the use of topical rapamycin as a chemopreventive agent in the context of solar simulated light (SSL)-induced skin carcinogenesis. In SKH-1 mice, topical rapamycin treatment decreased tumor yields when applied after completion of 15 weeks of SSL exposure compared to controls. However, applying rapamycin during SSL exposure for 15 weeks, and continuing for 10 weeks after UV treatment, increased tumor yields. We also examined whether a combinatorial approach might result in more significant tumor suppression by rapamycin. We validated that rapamycin causes increased Akt (S473) phosphorylation in the epidermis after SSL, and show for the first time that this dysregulation can be inhibited in vivo by a selective PDK1/Akt inhibitor, PHT-427. Combining rapamycin with PHT-427 on tumor prone skin additively caused a significant reduction of tumor multiplicity compared to vehicle controls. Our findings indicate that patients taking rapamycin should avoid sun exposure, and that combining topical mTOR inhibitors and Akt inhibitors may be a viable chemoprevention option for individuals at high risk for cutaneous SCC.

Occult progression by Apc-deficient intestinal crypts as a target for chemoprevention

Science.gov (United States)

Liskay, R.Michael

2014-01-01

Although Apc mutation is widely considered an initiating event in colorectal cancer, little is known about the earliest stages of tumorigenesis following sporadic Apc loss. Therefore, we have utilized a novel mouse model that facilitates the sporadic inactivation of Apc via frameshift reversion of Cre in single, isolated cells and subsequently tracks the fates of Apc-deficient intestinal cells. Our results suggest that consistent with Apc being a ‘gatekeeper’, loss of Apc early in life during intestinal growth leads to adenomas or increased crypt fission, manifested by fields of mutant but otherwise normal-appearing crypts. In contrast, Apc loss occurring later in life has minimal consequences, with mutant crypts being less prone to either increased crypt fission or adenoma formation. Using the stem cell-specific Lgr5-CreER mouse, we generated different sized fields of Apc-deficient crypts via independent recombination events and found that field size correlates with progression to adenoma. To evaluate this early stage prior to adenoma formation as a therapeutic target, we examined the chemopreventive effects of sulindac on Apc-deficient occult crypt fission. We found that sulindac treatment started early in life inhibits the morphologically occult spread of Apc-deficient crypts and thus reduces adenoma numbers. Taken together these results suggest that: (i) earlier Apc loss promotes increased crypt fission, (ii) a field of Apc-deficient crypts, which can form via occult crypt fission or independent neighboring events, is an important intermediate between loss of Apc and adenoma formation and (iii) normal-appearing Apc-deficient crypts are potential unappreciated targets for cancer screening and chemoprevention. PMID:23996931

Selenium and Breast Cancer Chemoprevention

National Research Council Canada - National Science Library

Thompson, Henry J

2005-01-01

.... The intermediate biomarkers being studied are as follows: indicators of oxidative damage to cellular macromolecules such as DNA and lipids, indicators of IGF metabolic status, and cellular indicators of breast cancer risk...

Chemopreventive effects of free and bound phenolics associated to steep waters (nejayote) obtained after nixtamalization of different maize types.

Science.gov (United States)

Rojas-García, Carlos; García-Lara, Silverio; Serna-Saldivar, Sergio O; Gutiérrez-Uribe, Janet A

2012-03-01

Free and bound phenolics extracts from nejayote solids were obtained after optimally lime-cooking blue, normal white, red, normal yellow, high-carotenoid and quality protein maize types. The extraction yield ranged from 4.47 to 10.05%. Bound phenolics extracts had higher content of total phenolics, antioxidant activity and ferulic acid compared to the free phenolics extracts. In general, free phenolics extracts were less cytotoxic than the bound phenolics counterparts. Bound phenolics extracts had higher induction of quinone reductase (QR) and particularly the normal yellow nejayote exerted the highest chemopreventive index tested in Hepa1c1c7 cells. When tested for monofunctional phase 2 induction capacity in BPrc1 cells, the bound phenolics extracts of blue, normal white and quality protein nejayotes were better inducers than the normal yellow counterpart. Particularly, the free phenolics extract of the white maize nejayote induced BPrc1 cells QR and exerted a higher chemopreventive index compared to the bound phenolics extract. Therefore, the nejayote of the normal white maize was the best source of monofunctional phase 2 enzyme inducers.

When defense becomes dangerous – transcription factor Nrf2 and cancer

Directory of Open Access Journals (Sweden)

Adam Krysztofiak

2015-01-01

Full Text Available The transcription factor Nrf2 controls the expression of genes encoding cytoprotective enzymes and proteins. Its activation is related to conformational changes in the inhibitory protein Keap1 and/or Nrf2 phosphorylation by upstream kinases. Activation of Nrf2 can lead to the induction of phase II enzymes responsible for the inactivation of potential carcinogens. This may constitute an important strategy of chemoprevention. Moreover, these enzymatic systems participating in the biotransformation of drugs can reduce their therapeutic effects, contributing to drug resistance. For this reason, a clear understanding of the role of Nrf2 is essential to assess the beneficial and adverse effects of its up-regulation, particularly in relation to the prevention and treatment of cancer. This article summarizes the current state of knowledge on the significance of Nrf2 in tumorigenesis.

Localized sequence-specific release of a chemopreventive agent and an anticancer drug in a time-controllable manner to enhance therapeutic efficacy.

Science.gov (United States)

Pan, Wen-Yu; Lin, Kun-Ju; Huang, Chieh-Cheng; Chiang, Wei-Lun; Lin, Yu-Jung; Lin, Wei-Chih; Chuang, Er-Yuan; Chang, Yen; Sung, Hsing-Wen

2016-09-01

Combination chemotherapy with multiple drugs commonly requires several injections on various schedules, and the probability that the drug molecules reach the diseased tissues at the proper time and effective therapeutic concentrations is very low. This work elucidates an injectable co-delivery system that is based on cationic liposomes that are adsorbed on anionic hollow microspheres (Lipos-HMs) via electrostatic interaction, from which the localized sequence-specific release of a chemopreventive agent (1,25(OH)2D3) and an anticancer drug (doxorubicin; DOX) can be thermally driven in a time-controllable manner by an externally applied high-frequency magnetic field (HFMF). Lipos-HMs can greatly promote the accumulation of reactive oxygen species (ROS) in tumor cells by reducing their cytoplasmic expression of an antioxidant enzyme (superoxide dismutase) by 1,25(OH)2D3, increasing the susceptibility of cancer cells to the cytotoxic action of DOX. In nude mice that bear xenograft tumors, treatment with Lipos-HMs under exposure to HFMF effectively inhibits tumor growth and is the most effective therapeutic intervention among all the investigated. These empirical results demonstrate that the synergistic anticancer effects of sequential release of 1,25(OH)2D3 and DOX from the Lipos-HMs may have potential for maximizing DOX cytotoxicity, supporting more effective cancer treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Phytochemicals from cruciferous vegetables, epigenetics, and prostate cancer prevention.

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W Watson, Gregory; M Beaver, Laura; E Williams, David; H Dashwood, Roderick; Ho, Emily

2013-10-01

Epidemiological evidence has demonstrated a reduced risk of prostate cancer associated with cruciferous vegetable intake. Follow-up studies have attributed this protective activity to the metabolic products of glucosinolates, a class of secondary metabolites produced by crucifers. The metabolic products of glucoraphanin and glucobrassicin, sulforaphane, and indole-3-carbinol respectively, have been the subject of intense investigation by cancer researchers. Sulforaphane and indole-3-carbinol inhibit prostate cancer by both blocking initiation and suppressing prostate cancer progression in vitro and in vivo. Research has largely focused on the anti-initiation and cytoprotective effects of sulforaphane and indole-3-carbinol through induction of phases I and II detoxification pathways. With regards to suppressive activity, research has focused on the ability of sulforaphane and indole-3-carbinol to antagonize cell signaling pathways known to be dysregulated in prostate cancer. Recent investigations have characterized the ability of sulforaphane and indole-3-carbinol derivatives to modulate the activity of enzymes controlling the epigenetic status of prostate cancer cells. In this review, we will summarize the well-established, "classic" non-epigenetic targets of sulforaphane and indole-3-carbinol, and highlight more recent evidence supporting these phytochemicals as epigenetic modulators for prostate cancer chemoprevention.

Efficacy of geraniol but not of β-ionone or their combination for the chemoprevention of rat colon carcinogenesis

Directory of Open Access Journals (Sweden)

A. Vieira

2011-06-01

Full Text Available β-ionone (βI, a cyclic isoprenoid, and geraniol (GO, an acyclic monoterpene, represent a promising class of dietary chemopreventive agents against cancer, whose combination could result in synergistic anticarcinogenic effects. The chemopreventive activities of βI and GO were evaluated individually or in combination during colon carcinogenesis induced by dimethylhydrazine in 48 3-week-old male Wistar rats (12 per group weighing 40-50 g. Animals were treated for 9 consecutive weeks with βI (16 mg/100 g body weight, GO (25 mg/100 g body weight, βI combined with GO or corn oil (control. Number of total aberrant crypt foci (ACF and of ACF ≥4 crypts in the distal colon was significantly lower in the GO group (66 ± 13 and 9 ± 2, respectively compared to control (102 ± 9 and 17 ± 3 and without differences in the βI (91 ± 11 and 14 ± 3 and βI+GO groups (96 ± 5 and 19 ± 2. Apoptosis level, identified by classical apoptosis morphological criteria, in the distal colon was significantly higher in the GO group (1.64 ± 0.06 apoptotic cells/mm² compared to control (0.91 ± 0.07 apoptotic cells/mm². The GO group presented a 0.7-fold reduction in Bcl-2 protein expression (Western blot compared to control. Colonic mucosa concentrations of βI and GO (gas chromatography/mass spectrometry were higher in the βI and GO groups, respectively, compared to the control and βI+GO groups. Therefore, GO, but not βI, represents a potential chemopreventive agent in colon carcinogenesis. Surprisingly, the combination of isoprenoids does not represent an efficient chemopreventive strategy.

Breast cancer prevention strategies in lobular carcinoma in situ: A decision analysis.

Science.gov (United States)

Wong, Stephanie M; Stout, Natasha K; Punglia, Rinaa S; Prakash, Ipshita; Sagara, Yasuaki; Golshan, Mehra

2017-07-15

Women diagnosed with lobular carcinoma in situ (LCIS) have a 3-fold to 10-fold increased risk of developing invasive breast cancer. The objective of this study was to evaluate the life expectancy (LE) and differences in survival offered by active surveillance, risk-reducing chemoprevention, and bilateral prophylactic mastectomy among women with LCIS. A Markov simulation model was constructed to determine average LE and quality-adjusted LE (QALE) gains for hypothetical cohorts of women diagnosed with LCIS at various ages under alternative risk-reduction strategies. Probabilities for invasive breast cancer, breast cancer-specific mortality, other-cause mortality and the effectiveness of preventive strategies were derived from published studies and from the National Cancer Institute's Surveillance, Epidemiology, and End Results database. Assuming a breast cancer incidence from 1.02% to 1.37% per year under active surveillance, a woman aged 50 years diagnosed with LCIS would have a total LE of 32.78 years and would gain 0.13 years (1.6 months) in LE by adding chemoprevention and 0.25 years (3.0 months) in LE by adding bilateral prophylactic mastectomy. After quality adjustment, chemoprevention resulted in the greatest QALE for women ages 40 to 60 years at LCIS diagnosis, whereas surveillance remained the preferred strategy for optimizing QALE among women diagnosed at age 65 years and older. In this model, among women with a diagnosis of LCIS, breast cancer prevention strategies only modestly affected overall survival, whereas chemoprevention was modeled as the preferred management strategy for optimizing invasive disease-free survival while prolonging QALE form women younger than 65 years. Cancer 2017;123:2609-17. © 2017 American Cancer Society. © 2017 American Cancer Society.

Chemopreventive Effects of Germinated Rough Rice Crude Extract in Inhibiting Azoxymethane-Induced Aberrant Crypt Foci Formation in Sprague-Dawley Rats

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Elnaz Saki

2017-01-01

Full Text Available Chemoprevention has become an important area in cancer research due to low success rate of current therapeutic modalities. Diet plays a vital role in the etiology of cancer. This research was carried out to study the chemopreventive properties of germinated rough rice (GRR crude extract in Sprague-Dawley rats induced with azoxymethane. Germination of rough rice causes significant changes in several chemical compositions of presently bioactive compounds. These compounds may prevent or postpone the inception of cancer. Fifty male Sprague-Dawley rats (6 weeks of age were randomly divided into 5 groups which were (G1 induced with azoxymethane (AOM and not given GRR (positive control, (G2 induced with AOM and given 2000 mg/kg GRR, (G3 induced with AOM and given 1000 mg/kg GRR, (G4 induced with AOM and given 500 mg/kg GRR, and (G5 not induced with AOM and not given GRR crude extract (negative control. To induce colon cancer, rats received two IP injections of AOM in saline (15 mg/kg for two subsequent weeks. Organs were removed and weighed. Aberrant crypt foci (ACF were evaluated histopathologically. β-Catenin expressions were determined by Western blot. Treatment with 2000 mg/kg GRR crude extract not only resulted in the greatest reduction in the size and number of ACF but also displayed the highest percentage of nondysplastic ACF. Treatment with 2000 mg/kg GRR also gave the lowest level of expression in β-catenin. Thus, GRR could be a promising dietary supplement for prevention of CRC.

Metabolic enzyme expression highlights a key role for MTHFD2 and the mitochondrial folate pathway in cancer

Science.gov (United States)

Nilsson, Roland; Jain, Mohit; Madhusudhan, Nikhil; Sheppard, Nina Gustafsson; Strittmatter, Laura; Kampf, Caroline; Huang, Jenny; Asplund, Anna; Mootha, Vamsi K.

2014-01-01

Metabolic remodeling is now widely regarded as a hallmark of cancer, but it is not clear whether individual metabolic strategies are frequently exploited by many tumours. Here we compare messenger RNA profiles of 1,454 metabolic enzymes across 1,981 tumours spanning 19 cancer types to identify enzymes that are consistently differentially expressed. Our meta-analysis recovers established targets of some of the most widely used chemotherapeutics, including dihydrofolate reductase, thymidylate synthase and ribonucleotide reductase, while also spotlighting new enzymes, such as the mitochondrial proline biosynthetic enzyme PYCR1. The highest scoring pathway is mitochondrial one-carbon metabolism and is centred on MTHFD2. MTHFD2 RNA and protein are markedly elevated in many cancers and correlated with poor survival in breast cancer. MTHFD2 is expressed in the developing embryo, but is absent in most healthy adult tissues, even those that are proliferating. Our study highlights the importance of mitochondrial compartmentalization of one-carbon metabolism in cancer and raises important therapeutic hypotheses.

Chemopreventive Activities of Sulforaphane and Its Metabolites in Human Hepatoma HepG2 Cells

Directory of Open Access Journals (Sweden)

Peng Liu

2018-05-01

Full Text Available Sulforaphane (SFN exhibits chemopreventive effects through various mechanisms. However, few studies have focused on the bioactivities of its metabolites. Here, three metabolites derived from SFN were studied, known as sulforaphane glutathione, sulforaphane cysteine and sulforaphane-N-acetylcysteine. Their effects on cell viability, DNA damage, tumorigenicity, cell migration and adhesion were measured in human hepatoma HepG2 cells, and their anti-angiogenetic effects were determined in a 3D co-culture model of human umbilical vein endothelial cells (HUVECs and pericytes. Results indicated that these metabolites at high doses decreased cancer cell viability, induced DNA damage and inhibited motility, and impaired endothelial cell migration and tube formation. Additionally, pre-treatment with low doses of SFN metabolites protected against H2O2 challenge. The activation of the nuclear factor E2-related factor 2 (Nrf2-antioxidant response element (ARE pathway and the induction of intracellular glutathione (GSH played an important role in the cytoprotective effects of SFN metabolites. In conclusion, SFN metabolites exhibited similar cytotoxic and cytoprotective effects to SFN, which proves the necessity to study the mechanisms of action of not only SFN but also of its metabolites. Based on the different tissue distribution profiles of these metabolites, the most relevant chemical forms can be selected for targeted chemoprevention.

Oral Carcinogenesis and Oral Cancer Chemoprevention: A Review

OpenAIRE

Tanaka, Takuji; Tanaka, Mayu; Tanaka, Takahiro

2011-01-01

Oral cancer is one of the major global threats to public health. The development of oral cancer is a tobacco-related multistep and multifocal process involving field cancerization and carcinogenesis. The rationale for molecular-targeted prevention of oral cancer is promising. Biomarkers of genomic instability, including aneuploidy and allelic imbalance, are possible to measure the cancer risk of oral premalignancies. Understanding of the biology of oral carcinogenesis will yield important adv...

Nitric oxide-releasing sulindac is a novel skin cancer chemopreventive agent for UVB-induced photocarcinogenesis

Energy Technology Data Exchange (ETDEWEB)

Chaudhary, Sandeep C.; Singh, Tripti; Kapur, Puneet; Weng, Zhiping; Arumugam, Aadithya; Elmets, Craig A. [Department of Dermatology, University of Alabama at Birmingham, 1530 3rd Avenue South, VH509, Birmingham, AL 35294-0019 (United States); Kopelovich, Levy [Division of Cancer Prevention, National Cancer Institute, 6130 Executive Blvd, Suite 2114, Bethesda, MD 20892 (United States); Athar, Mohammad, E-mail: mathar@uab.edu [Department of Dermatology, University of Alabama at Birmingham, 1530 3rd Avenue South, VH509, Birmingham, AL 35294-0019 (United States)

2013-05-01

Nitric oxide (NO)-releasing non-steroidal anti-inflammatory drugs (NO-NSAIDs) which have been synthesized to reduce gastro-intestinal and cardiovascular toxicities of NSAIDs, possess anti-proliferative, pro-apoptotic and anti-cancer activities. Here, we show that NO-sulindac inhibited UVB-induced skin tumorigenesis in SKH-1 hairless mice. Topical application of NO-sulindac reduced tumor incidence, number (p < 0.05) and volume (p < 0.005) as compared to UVB (alone)-irradiated vehicle-treated mice. An increase in TUNEL-positive cells in skin lesions was accompanied by the enhanced Bax:Bcl-2 ratio. The expression of pro-apoptotic Bax was increased whereas anti-apoptotic Bcl-2 reduced. However, proliferation was identified as the major target of NO-sulindac in this study. A reduced expression of PCNA and cyclin D1 associated with the dampening of cell cycle progression was observed. The mechanism of this inhibition was related to the reduction in UVB-induced Notch signaling pathway. UVB-induced inflammatory responses were diminished by NO-sulindac as observed by a remarkable reduction in the levels of phosphorylated MAP Kinases Erk1/2, p38 and JNK1/2. In this regard, NO-sulindac also inhibited NFκB by enhancing IκBα as evidenced by the reduced expression of iNOS and COX-2, the direct NFκB transcription target proteins. NO-sulindac significantly diminished the progression of benign lesions to invasive carcinomas by suppressing the tumor aggressiveness and retarding epithelial–mesenchymal transition. A marked decrease in the expression of mesenchymal markers such as Fibronectin, N-cadherin, SNAI, Slug and Twist and an increase in epithelial cell polarity marker E-cadherin were noted in NO-sulindac-treated tumors. Our data suggest that NO-sulindac is a potent inhibitor of UVB-induced skin carcinogenesis and acts by targeting proliferation-regulatory pathways. - Highlights: ► NO-sulindac is a potent chemopreventive agent for UVB-induced skin cancer. ► NO

Chemopreventive effects of in vitro digested and fermented bread in human colon cells.

Science.gov (United States)

Schlörmann, Wiebke; Hiller, Beate; Jahns, Franziska; Zöger, Romy; Hennemeier, Isabell; Wilhelm, Anne; Lindhauer, Meinolf G; Glei, Michael

2012-10-01

Bread as a staple food product represents an important source for dietary fibre consumption. Effects of wheat bread, wholemeal wheat bread and wholemeal rye bread on mechanisms which could have impact on chemoprevention were analysed in colon cells after in vitro fermentation. Effects of fermented bread samples on gene expression, glutathione S-transferase activity and glutathione content, differentiation, growth and apoptosis were investigated using the human colon adenoma cell line LT97. Additionally, apoptosis was studied in normal and tumour colon tissue by determination of caspase activities. The expression of 76 genes (biotransformation, differentiation, apoptosis) was significantly upregulated (1.5-fold) in LT97 cells. The fermented bread samples were able to significantly increase glutathione S-transferase activity (1.8-fold) and glutathione content (1.4-fold) of the cells. Alkaline phosphatase activity as a marker of differentiation was also significantly enhanced (1.7-fold). The fermented bread samples significantly inhibited LT97 cell growth and increased the level of apoptotic cells (1.8-fold). Only marginal effects on apoptosis in tumour compared to normal tissue were observed. This is the first study which presents chemopreventive effects of different breads after in vitro fermentation. In spite of differences in composition, the results were comparable between the bread types. Nevertheless, they indicate a potential involvement of this staple food product regarding the prevention of colon cancer.

The inactivation of human CYP2E1 by phenethyl isothiocyanate, a naturally occurring chemopreventive agent, and its oxidative bioactivation.

Science.gov (United States)

Yoshigae, Yasushi; Sridar, Chitra; Kent, Ute M; Hollenberg, Paul F

2013-04-01

Phenethylisothiocyanate (PEITC), a naturally occurring isothiocyanate and potent cancer chemopreventive agent, works by multiple mechanisms, including the inhibition of cytochrome P450 (P450) enzymes, such as CYP2E1, that are involved in the bioactivation of carcinogens. PEITC has been reported to be a mechanism-based inactivator of some P450s. We describe here the possible mechanism for the inactivation of human CYP2E1 by PEITC, as well as the putative intermediate that might be involved in the bioactivation of PEITC. PEITC inactivated recombinant CYP2E1 with a partition ratio of 12, and the inactivation was not inhibited in the presence of glutathione (GSH) and not fully recovered by dialysis. The inactivation of CYP2E1 by PEITC is due to both heme destruction and protein modification, with the latter being the major pathway for inactivation. GSH-adducts of phenethyl isocyanate (PIC) and phenethylamine were detected during the metabolism by CYP2E1, indicating formation of PIC as a reactive intermediate following P450-catalyzed desulfurization of PEITC. Surprisingly, PIC bound covalently to CYP2E1 to form protein adducts but did not inactivate the enzyme. Liquid chromatography mass spectroscopy analysis of the inactivated CYP2E1 apo-protein suggests that a reactive sulfur atom generated during desulfurization of PEITC is involved in the inactivation of CYP2E1. Our data suggest that the metabolism of PEITC by CYP2E1 that results in the inactivation of CYP2E1 may occur by a mechanism similar to that observed with other sulfur-containing compounds, such as parathion. Digestion of the inactivated enzyme and analysis by SEQUEST showed that Cys 268 may be the residue modified by PIC.

Preferences for breast cancer risk reduction among BRCA1/BRCA2 mutation carriers: a discrete-choice experiment.

Science.gov (United States)

Liede, Alexander; Mansfield, Carol A; Metcalfe, Kelly A; Price, Melanie A; Snyder, Carrie; Lynch, Henry T; Friedman, Sue; Amelio, Justyna; Posner, Joshua; Narod, Steven A; Lindeman, Geoffrey J; Evans, D Gareth

2017-09-01

Unaffected women who carry BRCA1 or BRCA2 mutations face difficult choices about reducing their breast cancer risk. Understanding their treatment preferences could help us improve patient counseling and inform drug trials. The objective was to explore preferences for various risk-reducing options among women with germline BRCA1/2 mutations using a discrete-choice experiment survey and to compare expressed preferences with actual behaviors. A discrete-choice experiment survey was designed wherein women choose between hypothetical treatments to reduce breast cancer risk. The hypothetical treatments were characterized by the extent of breast cancer risk reduction, treatment duration, impact on fertility, hormone levels, risk of uterine cancer, and ease and mode of administration. Data were analyzed using a random-parameters logit model. Women were also asked to express their preference between surgical and chemoprevention options and to report on their actual risk-reduction actions. Women aged 25-55 years with germline BRCA1/2 mutations who were unaffected with breast or ovarian cancer were recruited through research registries at five clinics and a patient advocacy group. Between January 2015 and March 2016, 622 women completed the survey. Breast cancer risk reduction was the most important consideration expressed, followed by maintaining fertility. Among the subset of women who wished to have children in future, the ability to maintain fertility was the most important factor, followed by the extent of risk reduction. Many more women said they would take a chemoprevention drug than had actually taken chemoprevention. Women with BRCA1/2 mutations indicated strong preferences for breast cancer risk reduction and maintaining fertility. The expressed desire to have a safe chemoprevention drug available to them was not met by current chemoprevention options.

Piper betel leaf: a reservoir of potential xenohormetic nutraceuticals with cancer-fighting properties.

Science.gov (United States)

Gundala, Sushma R; Aneja, Ritu

2014-05-01

Plants contain a much greater diversity of bioactive compounds than any man-made chemical library. Heart-shaped Piper betel leaves are magnificent reservoirs of phenolic compounds with antiproliferative, antimutagenic, antibacterial, and antioxidant properties. Widely consumed in South Asian countries, the glossy leaf contains a multitude of biophenolics such as hydroxychavicol, eugenol, chavibetol, and piperols. Convincing data underscore the remarkable chemotherapeutic and chemopreventive potential of betel leaves against a variety of cancer types. The leaf constituents modulate an extensive array of signaling molecules such as transcription factors as well as reactive oxygen species (ROS) to control multiple nodes of various cellular proliferation and death pathways. Herein, we provide an overall perspective on the cancer-fighting benefits of the phenolic phytochemicals in betel leaves and a comprehensive overview of the mechanisms responsive to dose-driven ROS-mediated signaling cascades conscripted by bioactive phenolics to confer chemotherapeutic and chemopreventive advantages. Intriguingly, these ROS-triggered responses are contextual and may either elicit a protective xenohormetic antioxidant response to premalignant cells to constitute a chemopreventive effect or generate a curative chemotherapeutic response by pro-oxidatively augmenting the constitutively elevated ROS levels in cancer cells to tip the balance in favor of selective apoptosis induction in cancer cells while sparing normal ones. In conclusion, this review provides an update on how distinct ROS levels exist in normal versus cancer cells and how these levels can be strategically modulated and exploited for therapeutic gains. We emphasize the yet untapped potential of the evergreen vine, betel leaf, for chemopreventive and chemotherapeutic management of cancer.

Chemoprevention of colon carcinogenesis by polyethylene glycol: suppression of epithelial proliferation via modulation of SNAIL/beta-catenin signaling.

Science.gov (United States)

Roy, Hemant K; Kunte, Dhananjay P; Koetsier, Jennifer L; Hart, John; Kim, Young L; Liu, Yang; Bissonnette, Marc; Goldberg, Michael; Backman, Vadim; Wali, Ramesh K

2006-08-01

Polyethylene glycol (PEG) is one of the most potent chemopreventive agents against colorectal cancer; however, the mechanisms remain largely unexplored. In this study, we assessed the ability of PEG to target cyclin D1-beta-catenin-mediated hyperproliferation in the azoxymethane-treated rat model and the human colorectal cancer cell line, HT-29. Azoxymethane-treated rats were randomized to AIN-76A diet alone or supplemented with 5% PEG-8000. After 30 weeks, animals were euthanized and biopsies of aberrant crypt foci and uninvolved crypts were subjected to immunohistochemical and immunoblot analyses. PEG markedly suppressed both early and late markers of azoxymethane-induced colon carcinogenesis (fractal dimension by 80%, aberrant crypt foci by 64%, and tumors by 74%). In both azoxymethane-treated rats and HT-29 cells treated with 5% PEG-3350 for 24 hours, PEG decreased proliferation (45% and 52%, respectively) and cyclin D1 (78% and 56%, respectively). Because beta-catenin is the major regulator of cyclin D1 in colorectal cancer, we used the T-cell factor (Tcf)-TOPFLASH reporter assay to show that PEG markedly inhibited beta-catenin transcriptional activity. PEG did not alter total beta-catenin expression but rather its nuclear localization, leading us to assess E-cadherin expression (a major determinant of beta-catenin subcellular localization), which was increased by 73% and 71% in the azoxymethane-rat and HT-29 cells, respectively. We therefore investigated the effect of PEG treatment on levels of the negative regulator of E-cadherin, SNAIL, and observed a 50% and 75% decrease, respectively. In conclusion, we show, for the first time, a molecular mechanism through which PEG imparts its antiproliferative and hence profound chemopreventive effect.

The relevance of piroxicam for the prevention and treatment of nonmelanoma skin cancer and its precursors.

Science.gov (United States)

Campione, Elena; Paternò, Evelin Jasmine; Candi, Eleonora; Falconi, Mattia; Costanza, Gaetana; Diluvio, Laura; Terrinoni, Alessandro; Bianchi, Luca; Orlandi, Augusto

2015-01-01

Piroxicam (PXM), a nonsteroidal anti-inflammatory drug, is an enolic benzothiazine and a potent member of the oxicam series. The drug suppresses the synthesis of proinflammatory enzymes, such as cyclo-oxygenases-1 and -2 (COX-1 and 2), downregulates the production of prostaglandins (PGs) and tromboxanes, and inhibits polyamines production by blocking ornithine decarboxylase induction involved in nonmelanoma skin carcinogenesis. In addition, PXM is able to induce tumor cell apoptosis and suppresses metalloproteinase 2 activities. Skin carcinogenesis is a multistep process in which the accumulation of genetic events leads to a gradually dysplastic cellular expression, deregulation of cell growth, and carcinomatous progression. COX-1 upregulation plays a significant role in PG and vascular epidermal growth factor production supporting tumor growth. Increased level of PGs in premalignant and/or malignant cutaneous tumors is also favored by upregulation of COX-2 and downregulation of the tumor suppressor gene 15-hydroxy-prostaglandin dehydrogenase. Chemoprevention can be a hopeful approach to inhibit carcinoma occurrence before an invasive tumor develops. The chemopreventive effect of nonsteroidal anti-inflammatory drugs on nonmelanoma skin cancers has been established. In this study, we highlighted the different modalities of action of PXM on the pathogenesis of nonmelanoma skin cancer, analyzing and evaluating binding modes and energies between COX-1 or COX-2 and PXM by protein-ligand molecular docking. Our clinical experience about the local use of PXM on actinic keratoses and field cancerization is also reported, confirming its efficacy as target therapy.

Proteomic Profiling Reveals That Resveratrol Inhibits HSP27 Expression and Sensitizes Breast Cancer Cells to Doxorubicin Therapy

OpenAIRE

D?az-Ch?vez, Jos?; Fonseca-S?nchez, Miguel A.; Arechaga-Ocampo, Elena; Flores-P?rez, Ali; Palacios-Rodr?guez, Yadira; Dom?nguez-G?mez, Guadalupe; Marchat, Laurence A.; Fuentes-Mera, Lizeth; Mendoza-Hern?ndez, Guillermo; Gariglio, Patricio; L?pez-Camarillo, C?sar

2013-01-01

The use of chemopreventive natural compounds represents a promising strategy in the search for novel therapeutic agents in cancer. Resveratrol (3,4',5-trans-trihydroxystilbilene) is a dietary polyphenol found in fruits, vegetables and medicinal plants that exhibits chemopreventive and antitumor effects. In this study, we searched for modulated proteins with preventive or therapeutic potential in MCF-7 breast cancer cells exposed to resveratrol. Using two-dimensional electrophoresis we found s...

A small-molecule inhibitor of the ubiquitin activating enzyme for cancer treatment.

Science.gov (United States)

Hyer, Marc L; Milhollen, Michael A; Ciavarri, Jeff; Fleming, Paul; Traore, Tary; Sappal, Darshan; Huck, Jessica; Shi, Judy; Gavin, James; Brownell, Jim; Yang, Yu; Stringer, Bradley; Griffin, Robert; Bruzzese, Frank; Soucy, Teresa; Duffy, Jennifer; Rabino, Claudia; Riceberg, Jessica; Hoar, Kara; Lublinsky, Anya; Menon, Saurabh; Sintchak, Michael; Bump, Nancy; Pulukuri, Sai M; Langston, Steve; Tirrell, Stephen; Kuranda, Mike; Veiby, Petter; Newcomb, John; Li, Ping; Wu, Jing Tao; Powe, Josh; Dick, Lawrence R; Greenspan, Paul; Galvin, Katherine; Manfredi, Mark; Claiborne, Chris; Amidon, Benjamin S; Bence, Neil F

2018-02-01

The ubiquitin-proteasome system (UPS) comprises a network of enzymes that is responsible for maintaining cellular protein homeostasis. The therapeutic potential of this pathway has been validated by the clinical successes of a number of UPS modulators, including proteasome inhibitors and immunomodulatory imide drugs (IMiDs). Here we identified TAK-243 (formerly known as MLN7243) as a potent, mechanism-based small-molecule inhibitor of the ubiquitin activating enzyme (UAE), the primary mammalian E1 enzyme that regulates the ubiquitin conjugation cascade. TAK-243 treatment caused depletion of cellular ubiquitin conjugates, resulting in disruption of signaling events, induction of proteotoxic stress, and impairment of cell cycle progression and DNA damage repair pathways. TAK-243 treatment caused death of cancer cells and, in primary human xenograft studies, demonstrated antitumor activity at tolerated doses. Due to its specificity and potency, TAK-243 allows for interrogation of ubiquitin biology and for assessment of UAE inhibition as a new approach for cancer treatment.

Andrographolide and analogues in cancer prevention.

Science.gov (United States)

Mishra, Siddhartha Kumar; Tripathi, Swati; Shukla, Archana; Oh, Seung Hyun; Kim, Hwan Mook

2015-01-01

Andrographis paniculata is a medicinal plant traditionally used for treatment of cough and cold, fever, laryngitis, and several infectious diseases. Extracts of A. paniculata have shown versatile potency against various diseases including cancer. The active biomolecules of A. paniculata mainly are lactone and diterpene. Andrographolide and analogues have been widely used for prevention of different diseases. Andrographolides have shown potent antiinflammatory and anticancer activities. It showed potentials as chemopreventive agents by suppressing growth of cancer cells by inhibiting NF-kappaB, PI3K/AKT and other kinase pathways and by inducing apoptosis. Andrographolide induced both intrinsic and extrinsic apoptosis pathway in different cancer cells via expression of different anti-apoptotic protein like Bax, p53, and activated caspases. Andrographolide was successfully used as an antineoplastic drug in cancer chemotherapy. Andrographolide inhibited the growth of human breast, prostate, and hepatoma tumors. Andrographolide and analogues need to be subjected to further clinical and biomedical studies in cancer chemoprevention. Andrographolide could be potent anticancer agent when used in combination with other chemotherapeutic agents.

Aspirin in the Chemoprevention of Colorectal Neoplasia: An Overview

Science.gov (United States)

Chan, Andrew T.; Arber, Nadir; Burn, John; Chia, John Whay-Kuang; Elwood, Peter; Hull, Mark A.; Logan, Richard F.; Rothwell, Peter M.; Schrör, Karsten; Baron, John A.

2011-01-01

Considerable evidence supports the effectiveness of aspirin for chemoprevention of colorectal cancer (CRC) in addition to its well-established benefits in the prevention of vascular disease. Epidemiologic studies have consistently observed an inverse association between aspirin use and risk of CRC. A recent pooled analysis of a long-term post-trial follow-up of nearly 14,000 patients from 4 randomized, cardiovascular disease prevention trials showed that daily aspirin treatment for about 5 years was associated with a 34% reduction in 20-year CRC mortality. A separate meta-analysis of nearly 3,000 patients with a history of colorectal adenoma or cancer in 4 randomized adenoma prevention trials demonstrated that aspirin reduced the occurrence of advanced adenomas by 28% and any adenoma by 17%. Aspirin has also been shown to be beneficial in a clinical trial of patients with Lynch syndrome, a hereditary CRC syndrome; in those treated with aspirin for at least 2 years, there was a ≥ 50% reduction in the risk of CRC commencing 5 years after randomization and after aspirin had been discontinued. A few observational studies have shown an increase in survival among patients with CRC who use aspirin. Taken together, these findings strengthen the case for consideration of long-term aspirin use in CRC prevention. Despite these compelling data, there is a lack of consensus about the balance of risks and benefits associated with long-term aspirin use, particularly in low-risk populations. The optimal dose to use for cancer prevention and the precise mechanism underlying aspirin’s anticancer effect require further investigation. PMID:22084361

Procyanidins from wild grape (Vitis amurensis) seeds regulate ARE-mediated enzyme expression via Nrf2 coupled with p38 and PI3K/Akt pathway in HepG2 cells.

Science.gov (United States)

Bak, Min-Ji; Jun, Mira; Jeong, Woo-Sik

2012-01-01

Procyanidins, polymers of flavan-3-ol units, have been reported to exhibit many beneficial health effects such as antioxidant and anti-carcinogenic effects. In this study, we investigated the cancer chemopreventive properties of procyanidins from wild grape (Vitis amurensis) seeds in particular their roles in inducing phase II detoxifying/antioxidant enzymes as well as in modulating the upstream kinases. Ethanolic extract of V. amurensis seeds was fractionated with a series of organic solvents and finally separated into six fractions, F1-F6. Chemical properties of the procyanidins were analyzed by vanillin assay, BuOH-HCl test, and depolymerization with phloroglucinol followed by LC/MS analysis. The F5 had the highest procyanidin content among all the fractions and strongly induced the reporter activity of antioxidant response element as well as the protein expression of nuclear factor E2-related factor (Nrf2) in HepG2 human hepatocarcinoma cells. The procyanidin-rich F5 also strongly induced the expression of the phase II detoxifying and antioxidant enzymes such as NAD(P)H:quinone oxidoreductase1 and hemeoxygenase1. Phosphorylations of the upstream kinases such as MAPKs and PI3K/Akt were significantly increased by treatment with procyanidin fraction. In addition, the procyanidin-mediated Nrf2 expression was partly attenuated by PI3K inhibitor LY294002, and almost completely by p38 inhibitor SB202190, but neither by JNK inhibitor SP600125 nor by MEK1/2 inhibitor U0126. Taken together, the procyanidins from wild grape seeds could be used as a potential natural chemopreventive agent through Nrf2/ARE-mediated phase II detoxifying/antioxidant enzymes induction via p38 and PI3K/Akt pathway.

Effect of Food Sources of Natural Chemo preventive Agents on ...

African Journals Online (AJOL)

Objective: The work attempted to evaluate the potential of natural products containing cancer chemopreventive agents in increasing the level of some endogenous antioxidant enzymes such as Glutathione STransferase (GST), Glutathione reductase (GR), catalase, superoxide dismutase(SOD-1,2) in brain and kidney ...

Sulindac treatment in hereditary non-pollyposis colorectal cancer

NARCIS (Netherlands)

Rijcken, Fleur E. M.; Hollema, Harry; van der Zee, Ate G. J.; van der Sluis, Tineke; Ek, Wytske Boersma-van; Kleibeuker, Jan H.

Non-steroidal anti-inflammatory drugs, e.g. sulindac have been extensively studied for chemoprevention in familial adenomatous polyposis, but not in hereditary non-polyposis colorectal cancer (HNPCC). We evaluated these effects in HNPCC using surrogate end-points for cancer risk. In a randomised

Modulation of xenobiotic metabolising enzymes by anticarcinogens-focus on glutathione S-transferases and their role as targets of dietary chemoprevention in colorectal carcinogenesis

Energy Technology Data Exchange (ETDEWEB)

Pool-Zobel, Beatrice [Department of Nutritional Toxicology, Institute for Nutrition, Friedrich Schiller University Jena, 07743 Jena (Germany)]. E-mail: b8pobe@uni-jena.de; Veeriah, Selvaraju [Department of Nutritional Toxicology, Institute for Nutrition, Friedrich Schiller University Jena, 07743 Jena (Germany); Boehmer, Frank-D. [Institute of Molecular Cell Biology, University Hospital, Friedrich Schiller University Jena, 07743 Jena (Germany)

2005-12-11

There is evidence that consumption of certain dietary ingredients may favourably modulate biotransformation of carcinogens. Associated with this is the hypothesis that the risk for developing colorectal cancer could be reduced, since its incidence is related to diet. Two main groups of biotransformation enzymes metabolize carcinogens, namely Phase I enzymes, which convert hydrophobic compounds to more water-soluble moieties, and Phase II enzymes (e.g. glutathione S-transferases [GST]), which primarily catalyze conjugation reactions. The conjugation of electrophilic Phase I intermediates with glutathione, for instance, frequently results in detoxification. Several possible colon carcinogens may serve as substrates for GST isoenzymes that can have marked substrate specificity. The conjugated products could be less toxic/genotoxic if GSTs are induced, thereby reducing exposure. Thus, numerous studies have shown that the induction of GSTs by antioxidants enables experimental animals to tolerate exposure to carcinogens. One important mechanism of GST induction involves an antioxidant-responsive response element (ARE) and the transcription factor nuclear factor E2-related factor 2 (Nrf2), which is bound to the Kelch-like ECH associated protein 1 (Keap1) in the cytoplasm. Antioxidants may disrupt the Keap-Nrf2 complex, allowing Nrf2 to translocate to the nucleus and mediate expression of Phase II genes via interaction with the ARE. GSTs are also induced by butyrate, a product of gut flora-derived fermentation of plant foods, which may act via different mechanisms, e.g. by increasing histone acetylation. GSTs are expressed with high inter-individual variability in human colonocytes, which points to large differences in cellular susceptibility to xenobiotics. Enhancing expression of GSTs in human colon tissue could therefore contribute to reducing cancer risks. However, it has not been demonstrated in humans that this mechanism is associated with cancer prevention. In the

Modulation of xenobiotic metabolising enzymes by anticarcinogens-focus on glutathione S-transferases and their role as targets of dietary chemoprevention in colorectal carcinogenesis

International Nuclear Information System (INIS)

Pool-Zobel, Beatrice; Veeriah, Selvaraju; Boehmer, Frank-D.

2005-01-01

There is evidence that consumption of certain dietary ingredients may favourably modulate biotransformation of carcinogens. Associated with this is the hypothesis that the risk for developing colorectal cancer could be reduced, since its incidence is related to diet. Two main groups of biotransformation enzymes metabolize carcinogens, namely Phase I enzymes, which convert hydrophobic compounds to more water-soluble moieties, and Phase II enzymes (e.g. glutathione S-transferases [GST]), which primarily catalyze conjugation reactions. The conjugation of electrophilic Phase I intermediates with glutathione, for instance, frequently results in detoxification. Several possible colon carcinogens may serve as substrates for GST isoenzymes that can have marked substrate specificity. The conjugated products could be less toxic/genotoxic if GSTs are induced, thereby reducing exposure. Thus, numerous studies have shown that the induction of GSTs by antioxidants enables experimental animals to tolerate exposure to carcinogens. One important mechanism of GST induction involves an antioxidant-responsive response element (ARE) and the transcription factor nuclear factor E2-related factor 2 (Nrf2), which is bound to the Kelch-like ECH associated protein 1 (Keap1) in the cytoplasm. Antioxidants may disrupt the Keap-Nrf2 complex, allowing Nrf2 to translocate to the nucleus and mediate expression of Phase II genes via interaction with the ARE. GSTs are also induced by butyrate, a product of gut flora-derived fermentation of plant foods, which may act via different mechanisms, e.g. by increasing histone acetylation. GSTs are expressed with high inter-individual variability in human colonocytes, which points to large differences in cellular susceptibility to xenobiotics. Enhancing expression of GSTs in human colon tissue could therefore contribute to reducing cancer risks. However, it has not been demonstrated in humans that this mechanism is associated with cancer prevention. In the

Suppression of proliferation and oxidative stress by extracts of Ganoderma lucidum in the ovarian cancer cell line OVCAR-3.

Science.gov (United States)

Hsieh, Tze-Chen; Wu, Joseph M

2011-12-01

Lingzhi (LZ) is a medical mushroom also known as Ganoderma lucidum, which has been used in traditional Chinese medicine for more than 4,000 years and moreover, due to its presumed health benefits and apparent absence of side-effects it has also been widely consumed as a dietary supplement by cancer patients and by individuals diagnosed with various chronic diseases. The reported benefits of Ganoderma lucidum may be largely ascribed to its biologically active constituent polysaccharides and triterpenes known as ganoderic acids having structural similarity to steroid hormones. Laboratory studies have shown that Ganoderma lucidum enhances immune functions and also inhibits growth of various cancer cells both in vitro and in vivo. However, the mechanism by which Ganoderma lucidum exerts its chemopreventive activities remains unknown. In this study, we investigated whether Ganoderma lucidum elicits its anti-tumor effects by suppressing cell growth and inducing antioxidative/detoxification activity in human ovarian OVCAR-3 cells. The results showed that Ganoderma lucidum inhibits cell growth and disruption of cell cycle progression via down regulation of cyclin D1. Chemopreventive activities elicited by Ganoderma lucidum were demonstrated by the induction of antioxidant SOD and catalase as well as the phase II detoxification enzyme NAD(P)H:quinone oxidoreductase 1 (NQO1) and glutathione S-transferase P1 (GSTP1) via the Nrf2 mediated signaling pathway known to provide chemoprotection against carcinogenicity. These findings indicate that Ganoderma lucidum possesses chemopreventive potential contributing to its overall health effects and further suggest that Ganoderma lucidum may have clinical applications as an adjunct supplementary agent in chemotherapy.

Quantification of 4'-geranyloxyferulic acid, a new natural colon cancer chemopreventive agent, by HPLC-DAD in grapefruit skin extract.

Science.gov (United States)

Genovese, S; Epifano, F; Carlucci, G; Marcotullio, M C; Curini, M; Locatelli, M

2010-10-10

Oxyprenylated natural products (isopentenyloxy-, geranyloxy- and the less spread farnesyloxy-compounds and their biosynthetic derivatives) represent a family of secondary metabolites that have been consider for years merely as biosynthetic intermediates of the most abundant C-prenylated derivatives. Many of the isolated oxyprenylated natural products were shown to exert in vitro and in vivo remarkable anti-cancer and anti-inflammatory effects. 4'-Geranyloxyferulic acid [3-(4'-geranyloxy-3'-methoxyphenyl)-2-trans-propenoic] has been discovered as a valuable chemopreventive agent of several types of cancer. After development of a high yield and "eco-friendly" synthetic scheme of this secondary metabolite, starting from cheap and non-toxic reagents and substrates, we developed a new HPLC-DAD method for its quantification in grapefruit skin extract. A preliminary study on C18 column showed the separation between GOFA and boropinic acid (having the same core but with an isopentenyloxy side chain), used as internal standard. The tested column were thermostated at 28+/-1 degrees C and the separation was achieved in gradient condition at a flow rate of 1 mL/min with a starting mobile phase of H(2)O:methanol (40:60, v/v, 1% formic acid). The limit of detection (LOD, S/N=3) was 0.5 microg/mL and the limit of quantification (LOQ, S/N=10) was 1 microg/mL. Matrix-matched standard curves showed linearity up to 75 microg/mL. In the analytical range the precision (RSD%) values were extract of grapefruit. In conclusion, this method showed LOQ values able to selective quantification of this analyte in grapefruit skin extract.

Investigation of nuclear nano-morphology marker as a biomarker for cancer risk assessment using a mouse model

Science.gov (United States)

Bista, Rajan K.; Uttam, Shikhar; Hartman, Douglas J.; Qiu, Wei; Yu, Jian; Zhang, Lin; Brand, Randall E.; Liu, Yang

2012-06-01

The development of accurate and clinically applicable tools to assess cancer risk is essential to define candidates to undergo screening for early-stage cancers at a curable stage or provide a novel method to monitor chemoprevention treatments. With the use of our recently developed optical technology--spatial-domain low-coherence quantitative phase microscopy (SL-QPM), we have derived a novel optical biomarker characterized by structure-derived optical path length (OPL) properties from the cell nucleus on the standard histology and cytology specimens, which quantifies the nano-structural alterations within the cell nucleus at the nanoscale sensitivity, referred to as nano-morphology marker. The aim of this study is to evaluate the feasibility of the nuclear nano-morphology marker from histologically normal cells, extracted directly from the standard histology specimens, to detect early-stage carcinogenesis, assess cancer risk, and monitor the effect of chemopreventive treatment. We used a well-established mouse model of spontaneous carcinogenesis--ApcMin mice, which develop multiple intestinal adenomas (Min) due to a germline mutation in the adenomatous polyposis coli (Apc) gene. We found that the nuclear nano-morphology marker quantified by OPL detects the development of carcinogenesis from histologically normal intestinal epithelial cells, even at an early pre-adenomatous stage (six weeks). It also exhibits a good temporal correlation with the small intestine that parallels the development of carcinogenesis and cancer risk. To further assess its ability to monitor the efficacy of chemopreventive agents, we used an established chemopreventive agent, sulindac. The nuclear nano-morphology marker is reversed toward normal after a prolonged treatment. Therefore, our proof-of-concept study establishes the feasibility of the SL-QPM derived nuclear nano-morphology marker OPL as a promising, simple and clinically applicable biomarker for cancer risk assessment and

Phytochemicals attenuating aberrant activation of β-catenin in cancer cells.

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Dan Wang

Full Text Available Phytochemicals are a rich source of chemoprevention agents but their effects on modulating the Wnt/β-catenin signaling pathway have remained largely uninvestigated. Aberrantly activated Wnt signaling can result in the abnormal stabilization of β-catenin, a key causative step in a broad spectrum of cancers. Here we report the modulation of lithium chloride-activated canonical Wnt/β-catenin signaling by phytochemicals that have antioxidant, anti-inflammatory or chemopreventive properties. The compounds were first screened with a cervical cancer-derived stable Wnt signaling reporter HeLa cell line. Positive hits were subsequently evaluated for β-catenin degradation, suppression of β-catenin nuclear localization and down-regulation of downstream oncogenic targets of Wnt/β-catenin pathway. Our study shows a novel degradation path of β-catenin protein in HeLa cells by Avenanthramide 2p (a polyphenol and Triptolide (a diterpene triepoxide, respectively from oats and a Chinese medicinal plant. The findings present Avenanthramide 2p as a potential chemopreventive dietary compound that merits further study using in vivo models of cancers; they also provide a new perspective on the mechanism of action of Triptolide.

Evaluation of chemopreventive and cytotoxic effect of lemon seed extracts on human breast cancer (MCF-7) cells.

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Kim, Jinhee; Jayaprakasha, Guddadarangavvanahally K; Uckoo, Ram M; Patil, Bhimanagouda S

2012-02-01

Extracts from lemon seed were investigated for the radical scavenging activity and apoptotic effects in human breast adenocarcinoma (MCF-7) cells and non-malignant breast (MCF-12F) cells for the first time. Defatted seed powder was successively extracted with ethyl acetate (EtOAc), acetone, methanol (MeOH), and MeOH:water (80:20). The chemical constituents were identified and quantified by LC-MS and HPLC analysis, respectively. The highest radical scavenging activity of 62.2% and 91.3% was exhibited by MeOH:water (80:20) at 833μg/mL in 1,1-diphenyl-2-picryl hydrazyl (DPPH) and 2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS(+)), respectively. In addition, the MeOH:water (80:20) extract showed the highest (29.1%, Pwater (80:20) extract induced DNA fragmentation and poly(ADP-ribose) polymerase (PARP) cleavage. Increased levels of Bax and cytosolic cytochrome C and decreased levels of Bcl2 were also observed in MeOH:water (80:20) treated MCF-7 cells. In conclusion, the MeOH:water (80:20) extract from lemon seed has potent antioxidant activity and induces apoptosis in MCF-7 cells, leading to the inhibition of proliferation. These results suggest that aglycones and glucosides of the limonoids and flavonoid present in MeOH:water (80:20) extract may potentially serve as a chemopreventive agent for breast cancer. Copyright © 2011 Elsevier Ltd. All rights reserved.

Chemoprevention Trial of Selenium and Prostate Cancer

Science.gov (United States)

1999-10-01

use in slowing the growth of prostate cancer. This study will not use selenium as a treatment option for the possible cure of prostate cancer...slice or 1 piece o Q rj Chocolate candy and candy bars o o o o o Q o o c 1 small bar or 1 ounce ._> . ■Q Hard candy, jam, jelly, honey , or...your stream? Have you noticed any stress incontinence? (leakage of urine when sneezing, coughing or laughing) _1 -NOT AT ALL _ 2-LESS THAN 1 IN 5

A component of green tea (-)-epigallocatechin-3-gallate, promotes apoptosis in T24 human bladder cancer cells via modulation of the PI3K/Akt pathway and Bcl-2 family proteins

International Nuclear Information System (INIS)

Qin Jie; Xie Liping; Zheng Xiangyi; Wang Yunbin; Bai Yu; Shen Huafeng; Li Longcheng; Dahiya, Rajvir

2007-01-01

Bladder cancer is the fourth most common cancer in men and ninth most common in women. It has a protracted course of progression and is thus an ideal candidate for chemoprevention strategies and trials. This study was conducted to evaluate the chemopreventive/antiproliferative potential of (-)-epigallocatechin gallate (EGCG, the major phytochemical in green tea) against bladder cancer and its mechanism of action. Using the T24 human bladder cancer cell line, we found that EGCG treatment caused dose- and time-dependent inhibition of cellular proliferation and cell viability, and induced apoptosis. Mechanistically, EGCG inhibits phosphatidylinositol 3'-kinase/Akt activation that, in turn, results in modulation of Bcl-2 family proteins, leading to enhanced apoptosis of T24 cells. These findings suggest that EGCG may be an important chemoprevention agent for the management of bladder cancer

Breast Cancer Prevention (PDQ®)—Health Professional Version

Science.gov (United States)

Risk factors for breast cancer are female sex and advancing age, inherited risk, breast density, obesity, alcohol consumption, and exposure to ionizing radiation. Interventions to prevent breast cancer include chemoprevention (e.g. SERMs, AIs), risk-reducing surgery (e.g. mastectomy, oophorectomy). Review the evidence on risk factors and interventions to prevent breast cancer in this expert-reviewed summary.

Does a role for selenium in DNA damage repair explain apparent controversies in its use in chemoprevention?

Science.gov (United States)

Diamond, Alan M.

2013-01-01

The trace element selenium is an essential micronutrient that has received considerable attention for its potential use in the prevention of cancer. In spite of this interest, the mechanism(s) by which selenium might function as a chemopreventive remain to be determined. Considerable experimental evidence indicates that one possible mechanism by which selenium supplementation may exert its benefits is by enhancing the DNA damage repair response, and this includes data obtained using cultured cells, animal models as well as in human clinical studies. In these studies, selenium supplementation has been shown to be beneficial in reducing the frequency of DNA adducts and chromosome breaks, consequentially reducing the likelihood of detrimental mutations that ultimately contribute to carcinogenesis. The benefits of selenium can be envisioned as being due, at least in part, to it being a critical constituent of selenoproteins such as glutathione peroxidases and thioredoxin reductases, proteins that play important roles in antioxidant defence and maintaining the cellular reducing environment. Selenium, therefore, may be protective by preventing DNA damage from occurring as well as by increasing the activity of repair enzymes such as DNA glycosylases and DNA damage repair pathways that involve p53, BRCA1 and Gadd45. An improved understanding of the mechanism of selenium’s impact on DNA repair processes may help to resolve the apparently contradicting data obtained from decades of animal work, human epidemiology and more recently, clinical supplementation studies. PMID:23204505

Epigallocatechin Gallate Nanodelivery Systems for Cancer Therapy

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Andreia Granja

2016-05-01

Full Text Available Cancer is one of the leading causes of morbidity and mortality all over the world. Conventional treatments, such as chemotherapy, are generally expensive, highly toxic and lack efficiency. Cancer chemoprevention using phytochemicals is emerging as a promising approach for the treatment of early carcinogenic processes. (−-Epigallocatechin-3-gallate (EGCG is the major bioactive constituent in green tea with numerous health benefits including anti-cancer activity, which has been intensively studied. Besides its potential for chemoprevention, EGCG has also been shown to synergize with common anti-cancer agents, which makes it a suitable adjuvant in chemotherapy. However, limitations in terms of stability and bioavailability have hampered its application in clinical settings. Nanotechnology may have an important role in improving the pharmacokinetic and pharmacodynamics of EGCG. Indeed, several studies have already reported the use of nanoparticles as delivery vehicles of EGCG for cancer therapy. The aim of this article is to discuss the EGCG molecule and its associated health benefits, particularly its anti-cancer activity and provide an overview of the studies that have employed nanotechnology strategies to enhance EGCG’s properties and potentiate its anti-tumoral activity.

Perspectives of the Nrf-2 signaling pathway in cancer progression and therapy

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Priyanka Basak

Full Text Available The Nuclear factor erythroid2-related factor2 (Nrf2, a master regulator of redox homoeostasis, is a key transcription factor regulating a wide array of genes for antioxidant and detoxification enzymes. It protects organs from various kinds of toxic insults. On the other hand, activation of Nrf2 is also correlated with cancer progression and chemoresistance. Downregulation of Nrf2 activity has attracted an increasing amount of attention as it may provide an alternative cancer therapy. In this review, we examine recent studies on roles of Nrf2 in several pathophysiological conditions emphasising cancer. We discuss elaborately the current knowledge on Nrf2 regulation including KEAP1-dependent and KEAP1-independent cascades. KEAP1/Nrf2 system is a master regulator of cellular response against a variety of environmental stresses. We also highlight several tightly controlled regulations of Nrf2 by numerous proteins, small molecules, toxic metals, etc. In addition, we evaluate the possible therapeutic approaches of increasing chemosensitivity via modulating Nrf2 signaling. Keywords: Nrf2, Transcription factor, KEAP1, Oxidative stress, Cell proliferation, Carcinogenesis, Chemoprevention

Role of nitric oxide and antioxidant enzymes in the pathogenesis of oral cancer.

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Patel, Jayendrakumar B; Shah, Franky D; Shukla, Shilin N; Shah, Pankaj M; Patel, Prabhudas S

2009-01-01

Oral cancer is the leading malignancy in India. Nitric oxide and antioxidant enzymes play an important role in etiology of oral cancer. Therefore, the present study evaluates nitric oxide and antioxidant enzyme levels in healthy individual without tobacco habits (NHT, N=30) and healthy individuals with tobacco habits (WHT, n=90), patients with oral precancers (OPC, n=15) and oral cancer patients (n=126). Blood samples were collected from the subjects. NO2 + NO3 (nitrite+nitrate), superoxide dismutase (SOD) and catalase levels were estimated using highly specific spectrophotometeric methods. Statistical analysis was done by SPSS statistical software version 10. Mean plasma NO2 + NO3 levels were elevated in patients with OPC and oral cancer patients as compared to the controls. Mean activities of erythrocyte SOD and catalase were higher in WHT than NHT. Erythrocyte SOD and catalase levels were higher in WHT and patients with OPC as compared to NHT. The erythrocyte SOD and catalase activities were lower in oral cancer patients than patients with OPC. The erythrocyte SOD activity was higher in advanced oral cancer than the early disease. Erythrocyte catalase activity was lower in poorly differentiated tumors than well and moderately differentiated tumors. Pearson's correlation analysis revealed that alterations in plasma NO2 + NO3 levels were negatively associated with changes in erythrocyte SOD activities. The data revealed that the alterations in antioxidant activities were associated with production of nitric oxide in oral cancer, which may have significant role in oral carcinogenesis.

Co-regulation of histone-modifying enzymes in cancer.

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Abul B M M K Islam

Full Text Available Cancer is characterized by aberrant patterns of expression of multiple genes. These major shifts in gene expression are believed to be due to not only genetic but also epigenetic changes. The epigenetic changes are communicated through chemical modifications, including histone modifications. However, it is unclear whether the binding of histone-modifying proteins to genomic regions and the placing of histone modifications efficiently discriminates corresponding genes from the rest of the genes in the human genome. We performed gene expression analysis of histone demethylases (HDMs and histone methyltransferases (HMTs, their target genes and genes with relevant histone modifications in normal and tumor tissues. Surprisingly, this analysis revealed the existence of correlations in the expression levels of different HDMs and HMTs. The observed HDM/HMT gene expression signature was specific to particular normal and cancer cell types and highly correlated with target gene expression and the expression of genes with histone modifications. Notably, we observed that trimethylation at lysine 4 and lysine 27 separated preferentially expressed and underexpressed genes, which was strikingly different in cancer cells compared to normal cells. We conclude that changes in coordinated regulation of enzymes executing histone modifications may underlie global epigenetic changes occurring in cancer.

Oral chemoprevention with acetyl salicylic Acid, vitamin d and calcium reduces the risk of tobacco carcinogen-induced bladder tumors in mice

DEFF Research Database (Denmark)

Pommergaard, Hans-Christian; Burcharth, J; Rosenberg, J

2013-01-01

, and diet with chemoprevention (acetyl salicylic acid, 1-alpha 25(0H)2-vitamin D3 and calcium). There were significantly fewer tumors (0 (0-0) vs. 0 (0-2), p = .045) and fewer animals with tumors (0/20 vs. 5/20, p = .045) in the chemoprevention group compared with controls. Thus, chemoprevention diet...

Diet and prostate cancer - a holistic approach to management.

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Cheetham, Philippa J; Katz, Aaron E

2011-10-01

There is now increasing evidence from epidemiologic surveys and from laboratory, intervention, and case-control studies that diet and lifestyle plays a crucial role in prostate cancer biology and tumorigenesis. This applies to both the development and progression of prostate cancer, although in many cases the specific initiating factors in the diet are poorly understood. Conversely, many nutrients and herbs also show significant promise in helping to treat prostate cancer by slowing progression and reducing recurrence, ultimately reducing the risk of morbidity and mortality from the disease. Furthermore for all grades of prostate cancer, nutritional interventions complement conventional treatment to improve response and quality of life. Slowing or even reversing the progression of, high-grade prostate intraepithelial neoplasia [HGPIN]). with chemo-preventative agents could be the best primary defense against prostate cancer, preventing it from occurring in the first place. The information given in this review about prostate cancer chemoprevention summarizes the key evidence for the role of different dietary components and their effect on prostate cancer prevention and progression. Most nutritional chemoprevention agents also have the added benefit of being beneficial for the cardiovascular system, bone health and for the prevention of other cancers.

Procyanidins from Wild Grape (Vitis amurensis Seeds Regulate ARE-Mediated Enzyme Expression via Nrf2 Coupled with p38 and PI3K/Akt Pathway in HepG2 Cells

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Woo-Sik Jeong

2012-01-01

Full Text Available Procyanidins, polymers of flavan-3-ol units, have been reported to exhibit many beneficial health effects such as antioxidant and anti-carcinogenic effects. In this study, we investigated the cancer chemopreventive properties of procyanidins from wild grape (Vitis amurensis seeds in particular their roles in inducing phase II detoxifying/antioxidant enzymes as well as in modulating the upstream kinases. Ethanolic extract of V. amurensis seeds was fractionated with a series of organic solvents and finally separated into six fractions, F1–F6. Chemical properties of the procyanidins were analyzed by vanillin assay, BuOH-HCl test, and depolymerization with phloroglucinol followed by LC/MS analysis. The F5 had the highest procyanidin content among all the fractions and strongly induced the reporter activity of antioxidant response element as well as the protein expression of nuclear factor E2-related factor (Nrf2 in HepG2 human hepatocarcinoma cells. The procyanidin-rich F5 also strongly induced the expression of the phase II detoxifying and antioxidant enzymes such as NAD(PH:quinone oxidoreductase1 and hemeoxygenase1. Phosphorylations of the upstream kinases such as MAPKs and PI3K/Akt were significantly increased by treatment with procyanidin fraction. In addition, the procyanidin-mediated Nrf2 expression was partly attenuated by PI3K inhibitor LY294002, and almost completely by p38 inhibitor SB202190, but neither by JNK inhibitor SP600125 nor by MEK1/2 inhibitor U0126. Taken together, the procyanidins from wild grape seeds could be used as a potential natural chemopreventive agent through Nrf2/ARE-mediated phase II detoxifying/antioxidant enzymes induction via p38 and PI3K/Akt pathway.

Angiotensin-converting enzyme and its association with outcome in lung cancer.

OpenAIRE

R?mer, F. K.

1981-01-01

Serum angiotensin-converting enzyme (SACE) in 141 patients with newly detected primary lung cincer was 22.1 +/- 6.1 nmol/ml/min (mean +/- s.d.); lower than in healthy controls (24.4 +/- 6.2 nmol/ml/min, P less than 0.02). No correlation was found between SACE and sex, age, site of cancer, histological type, or lung function. After subdivision of the patients according to increasing SACE levels: less than 16.0 (mean SACE of lung cancer--s.d.), 16.0-22.0, 22.1-28.2 and greater than 28.2 nmol/ml...

Epigenetics of prostate cancer and the prospect of identification of novel drug targets by RNAi screening of epigenetic enzymes.

Science.gov (United States)

Björkman, Mari; Rantala, Juha; Nees, Matthias; Kallioniemi, Olli

2010-10-01

Alterations in epigenetic processes probably underlie most human malignancies. Novel genome-wide techniques, such as chromatin immunoprecipitation and high-throughput sequencing, have become state-of-the-art methods to map the epigenomic landscape of development and disease, such as in cancers. Despite these advances, the functional significance of epigenetic enzymes in cancer progression, such as prostate cancer, remain incompletely understood. A comprehensive mapping and functional understanding of the cancer epigenome will hopefully help to facilitate development of novel cancer therapy targets and improve future diagnostics. The authors have developed a novel cell microarray-based high-content siRNA screening technique suitable to address the putative functional role and impact of all known putative and novel epigenetic enzymes in cancer, including prostate cancer.

Potential Impact of Seasonal Malaria Chemoprevention on the Acquisition of Antibodies Against Glutamate-Rich Protein and Apical Membrane Antigen 1 in Children Living in Southern Senegal

DEFF Research Database (Denmark)

Ndiaye, Magatte; Sylla, Khadime; Sow, Doudou

2015-01-01

Seasonal malaria chemoprevention (SMC) is defined as the intermittent administration of full treatment courses of an antimalarial drug to children during the peak of malaria transmission season with the aim of preventing malaria-associated mortality and morbidity. SMC using sulfadoxine-pyrimetham......Seasonal malaria chemoprevention (SMC) is defined as the intermittent administration of full treatment courses of an antimalarial drug to children during the peak of malaria transmission season with the aim of preventing malaria-associated mortality and morbidity. SMC using sulfadoxine......-pyrimethamine (SP) combined with amodiaquine (AQ) is a promising strategy to control malaria morbidity in areas of highly seasonal malaria transmission. However, a concern is whether SMC can delay the natural acquisition of immunity toward malaria parasites in areas with intense SMC delivery. To investigate this......, total IgG antibody (Ab) responses to Plasmodium falciparum antigens glutamate-rich protein R0 (GLURP-R0) and apical membrane antigen 1 (AMA-1) were measured by enzyme-linked immunosorbent assay in Senegalese children under the age of 10 years in 2010 living in Saraya and Velingara districts (with SMC...

Flavonoids as Chemopreventive and Therapeutic Agents Against Lung Cancer

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Albert Cabrera

2014-05-01

Full Text Available The objective of the present review is to study the relationship between flavonoids and lung cancer, proposing that their regular consumption in Western diets could be beneficial for protecting patients against lung cancer. An extensive search of the scientific literature was performed in the following electronic specialized databases (PubMed central (PMC-NBCI, Elsevier Journal, SciELO Spain, Scirus, Science Direct, including studies in animals, cells, and humans, in order to establish the effect of flavonoids in the prevention and development of lung cancer. Although in vitro and animal studies show the potential ability of flavonoids to act against different types of cancers, especially against lung cancers, the diverse results reported within epidemiological studies, together with the lack of experiments in humans, are the major factors in limiting making dietary recommendations based on scientific evidence for the management of patients with lung cancer. Therefore, the authors of the present study recommend following the dietary health practice guidelines which promotes the consumption of food enriched in flavonoids and reflects the current state of knowledge of an effective and appropriate diet in lung cancer patients.Erratum in: Rev Esp Nutr Hum Diet. 2013;17(2:91-92Link: http://www.renhyd.org/index.php/renhyd/article/view/6/17

Biological Basis for Chemoprevention of Ovarian Cancer

National Research Council Canada - National Science Library

Berchuck, Andrew

2006-01-01

To achieve a better understanding of the etiology of ovarian cancer we have initiated a case-control study that considers genetic susceptibility epidemiologic risk factors and acquired genetic alterations...

Biomarkers of Selenium Chemoprevention of Prostate Cancer

National Research Council Canada - National Science Library

Dong, Yan

2003-01-01

The purpose of the present study was to examine the mechanism of selenium growth inhibition in PC-3 human prostate cancer cells Selenium retarded cell cycle progression at multiple transition points...

Molecular Mechanisms of Anticancer Effects of Phytoestrogens in Breast Cancer.

Science.gov (United States)

Hsieh, Chia-Jung; Hsu, Ya-Ling; Huang, Ya-Fang; Tsai, Eing-Mei

2018-01-01

Phytoestrogens derived from plants exert estrogenic as well as antiestrogenic effects and multiple actions within breast cancer cells. Chemopreventive properties of phytoestrogens have emerged from epidemiological observations. In recent clinical research studies, phytoestrogens are safe and may even protect against breast cancer. In this brief review, the molecular mechanisms of phytoestrogens on regulation of cell cycle, apoptosis, estrogen receptors, cell signaling pathways, and epigenetic modulations in relation to breast cancer are discussed. Phytoestrogens have a preferential affinity for estrogen receptor (ER)-β, which appears to be associated with antiproliferative and anticarcinogenic effects. Moreover, while phytoestrogens not only inhibit ER-positive but also ER-negative breast cancer cells, the possibility of epigenetic modulation playing an important role is also discussed. In conclusion, as there are multiple targets and actions of phytoestrogens, extensive research is still necessary. However, due to low toxicity, low cost, and easy availability, their potent chemoprevention effects deserve further study. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Prolyl hydroxylase domain enzymes: important regulators of cancer metabolism

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Yang M

2014-08-01

Full Text Available Ming Yang,1 Huizhong Su,1 Tomoyoshi Soga,2 Kamil R Kranc,3 Patrick J Pollard1 1Cancer Biology and Metabolism Group, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK; 2Institute for Advanced Biosciences, Keio University, Mizukami, Tsuruoka, Yamagata, Japan; 3MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, UK Abstract: The hypoxia-inducible factor (HIF prolyl hydroxylase domain enzymes (PHDs regulate the stability of HIF protein by post-translational hydroxylation of two conserved prolyl residues in its α subunit in an oxygen-dependent manner. Trans-4-prolyl hydroxylation of HIFα under normal oxygen (O2 availability enables its association with the von Hippel-Lindau (VHL tumor suppressor pVHL E3 ligase complex, leading to the degradation of HIFα via the ubiquitin-proteasome pathway. Due to the obligatory requirement of molecular O2 as a co-substrate, the activity of PHDs is inhibited under hypoxic conditions, resulting in stabilized HIFα, which dimerizes with HIFβ and, together with transcriptional co-activators CBP/p300, activates the transcription of its target genes. As a key molecular regulator of adaptive response to hypoxia, HIF plays important roles in multiple cellular processes and its overexpression has been detected in various cancers. The HIF1α isoform in particular has a strong impact on cellular metabolism, most notably by promoting anaerobic, whilst inhibiting O2-dependent, metabolism of glucose. The PHD enzymes also seem to have HIF-independent functions and are subject to regulation by factors other than O2, such as by metabolic status, oxidative stress, and abnormal levels of endogenous metabolites (oncometabolites that have been observed in some types of cancers. In this review, we aim to summarize current understandings of the function and regulation of PHDs in cancer with an emphasis on their roles in metabolism. Keywords: prolyl hydroxylase domain (PHD

Specialty Supplements and Prostate Cancer Risk in the VITamins And Lifestyle (VITAL) Cohort

Science.gov (United States)

Brasky, Theodore M.; Kristal, Alan R.; Navarro, Sandi L.; Lampe, Johanna W.; Patterson, Ruth E.; Peters, Ulrike; White, Emily

2011-01-01

Although there is evidence from studies of prostate cancer cell lines and rodent models that several supplements may have anti-inflammatory, anti-oxidant, or other anti-cancer properties, few epidemiologic studies have examined the association between non-vitamin, non-mineral, “specialty” supplement use and prostate cancer risk. Participants, 50–76 years, were 35,239 male members of the VITamins And Lifestyle (VITAL) cohort who were residents of western Washington State, and who completed an extensive baseline questionnaire in 2000–2002. Participants responded about their frequency (days/week) and duration (years) of specialty supplement uses. 1,602 incident invasive prostate cancers were obtained from the Surveillance, Epidemiology, and End Results registry. Multivariate-adjusted hazards ratios (HR) and 95% confidence intervals (95% CI) were estimated by Cox proportional hazards models. Any use of grapeseed supplements was associated with a 41% (HR 0.59, 95% CI: 0.40–0.86) reduced risk of total prostate cancer. There were no associations for use of chondroitin, co-enzyme Q10, fish oil, garlic, ginkgo biloba, ginseng, glucosamine, or saw palmetto. Grapeseed may be a potential chemopreventive agent, however as current evidence is limited, it should not yet be promoted for prevention of prostate cancer. PMID:21598177

Association of cancer metabolism-related proteins with oral carcinogenesis – indications for chemoprevention and metabolic sensitizing of oral squamous cell carcinoma?

Science.gov (United States)

2014-01-01

Background Tumor metabolism is a crucial factor for the carcinogenesis of oral squamous cell carcinoma (OSCC). Methods Expression of IGF-R1, glycolysis-related proteins (GLUT-1, HK 2, PFK-1, LDHA, TKTL1), mitochondrial enzymes (SDHA, SDHB, ATP synthase) were analyzed in normal oral mucosa (n = 5), oral precursor lesions (simple hyperplasia, n = 11; squamous intraepithelial neoplasia, SIN I-III, n = 35), and OSCC specimen (n = 42) by immunohistochemistry and real-time polymerase chain reaction (qPCR) analysis in OSCC cell lines. Metabolism-related proteins were correlated with proliferation activity (Ki-67) and apoptotic properties (TUNEL assay) in OSCC. Specificity of antibodies was confirmed by western blotting in cancer cell lines. Results Expression of IGF-R1, glycolysis-related proteins (GLUT-1, HK 2, LDHA, TKTL1), and mitochondrial enzymes (SDHA, SDHB, ATP synthase) were significantly increased in the carcinogenesis of OSCC. Metabolic active regions of OSCC were strongly correlated with proliferating cancer (Ki-67+) cells without detection of apoptosis (TUNEL assay). Conclusions This study provides the first evidence of the expression of IGF-R1, glycolysis-related proteins GLUT-1, HK 2, PFK-1, LDHA, and TKTL1, as well as mitochondrial enzymes SDHA, SDHB, and ATP synthase in the multi-step carcinogenesis of OSCC. Both, hypoxia-related glucose metabolism and mitochondrial oxidative phosphorylation characteristics are associated with the carcinogenesis of OSCC. Acidosis and OXPHOS may drive a metabolic shift towards the pentose phosphate pathway (PPP). Therefore, inhibition of the PPP, glycolysis, and targeted anti-mitochondrial therapies (ROS generation) by natural compounds or synthetic vitamin derivatives may act as sensitizer for apoptosis in cancer cells mediated by adjuvant therapies in OSCC. PMID:25048361

Breast cancer and steroid metabolizing enzymes: the role of progestogens.

Science.gov (United States)

Pasqualini, Jorge R

2009-12-01

It is well documented that breast tissue, both normal and cancerous, contains all the enzymatic systems necessary for the bioformation and metabolic transformation of estrogens, androgens and progesterone. These include sulfatases, aromatase, hydroxysteroid-dehydrogenases, sulfotransferases, hydroxylases and glucuronidases. The control of these enzymes plays an important role in the development and pathogenesis of hormone-dependent breast cancer. As discussed in this review, various progestogens including dydrogesterone and its 20alpha-dihydro-derivative, medrogestone, promegestone, nomegestrol acetate and norelgestromin can reduce intratissular levels of estradiol in breast cancer by blocking sulfatase and 17beta-hydroxysteroid-dehydrogenase type 1 activities. A possible correlation has been postulated between breast cell proliferation and estrogen sulfotransferase activity. Progesterone is largely transformed in the breast; normal breast produces mainly 4-ene derivatives, whereas 5alpha-derivatives are most common in breast cancer tissue. It has been suggested that this specific conversion of progesterone may be involved in breast carcinogenesis. In conclusion, treatment with anti-aromatases combined with anti-sulfatase or 17beta-hydroxysteroid-dehydrogenase type 1 could provide new therapeutic possibilities in the treatment of patients with hormone-dependent breast cancer. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

Mitochondrial Enzyme Plays Critical Role in Chemotherapy-Induced Heart Damage | Center for Cancer Research

Science.gov (United States)

Doxorubicin (DOX) is an effective drug for treating cancers ranging from leukemia and lymphoma to solid tumors, such as breast cancer. DOX kills dividing cells in two ways: inserting between the base pairs of DNA and trapping a complex of DNA and an enzyme that cuts DNA, topoisomerase 2α, preventing DNA repair. However, DOX also causes congestive heart failure in about 30

Resveratrol: A review of preclinical studies for human cancer prevention

International Nuclear Information System (INIS)

Athar, Mohammad; Back, Jung Ho; Tang Xiuwei; Kim, Kwang Ho; Kopelovich, Levy; Bickers, David R.; Kim, Arianna L.

2007-01-01

The search for novel and effective cancer chemopreventive agents has led to the identification of various naturally occurring compounds one of which is resveratrol (trans-3,4',5-trihydroxystilbene), a phytoalexin derived from the skin of grapes and other fruits. Resveratrol is known to have potent anti-inflammatory and antioxidant effects and to inhibit platelet aggregation and the growth of a variety of cancer cells. Its potential chemopreventive and chemotherapeutic activities have been demonstrated in all three stages of carcinogenesis (initiation, promotion, and progression), in both chemically and UVB-induced skin carcinogenesis in mice, as well as in various murine models of human cancers. Evidence from numerous in vitro and in vivo studies has confirmed its ability to modulate various targets and signaling pathways. This review discusses the current preclinical and mechanistic data available and assesses resveratrol's anticancer effects to support its potential as an anticancer agent in human populations

Potent Skin Cancer Chemopreventing Activity of Some Novel Semi-synthetic Cembranoids from Marine Sources

OpenAIRE

Fahmy, Hesham; Zjawiony, Jordan K.; Konoshima, Takao; Tokuda, Harukuni; Khan, Shabana; Khalifa, Sherief

2006-01-01

Abstract: In the course of our continuing research in development and evaluation of novel skin cancer chemopreventive agents from marine sources, five semi-synthetic cembranoids derived from the marine natural product sarcophine, isolated from the soft coral Sarcophyton glaucum, were synthesized and shown to exhibit a remarkable chemopreventive activity in the in-vitro Epstein Barr Virus Early Antigen (EBV-EA) activation assay. These compounds were assayed in vivo using the two-stage carcinog...

Induction of apoptosis in human breast cancer cell line MCF-7 by ...

African Journals Online (AJOL)

Currently, breast cancer is the leading cause of cancer-related death in women. Therefore, there is an urgent need to develop alternative therapeutic measures against this deadly disease. Many components from dietary or medicinal plants have been identified that possess substantial chemopreventive properties. India has ...

Targeted enzyme prodrug therapies.

Science.gov (United States)

Schellmann, N; Deckert, P M; Bachran, D; Fuchs, H; Bachran, C

2010-09-01

The cure of cancer is still a formidable challenge in medical science. Long-known modalities including surgery, chemotherapy and radiotherapy are successful in a number of cases; however, invasive, metastasized and inaccessible tumors still pose an unresolved and ongoing problem. Targeted therapies designed to locate, detect and specifically kill tumor cells have been developed in the past three decades as an alternative to treat troublesome cancers. Most of these therapies are either based on antibody-dependent cellular cytotoxicity, targeted delivery of cytotoxic drugs or tumor site-specific activation of prodrugs. The latter is a two-step procedure. In the first step, a selected enzyme is accumulated in the tumor by guiding the enzyme or its gene to the neoplastic cells. In the second step, a harmless prodrug is applied and specifically converted by this enzyme into a cytotoxic drug only at the tumor site. A number of targeting systems, enzymes and prodrugs were investigated and improved since the concept was first envisioned in 1974. This review presents a concise overview on the history and latest developments in targeted therapies for cancer treatment. We cover the relevant technologies such as antibody-directed enzyme prodrug therapy (ADEPT), gene-directed enzyme prodrug therapy (GDEPT) as well as related therapies such as clostridial- (CDEPT) and polymer-directed enzyme prodrug therapy (PDEPT) with emphasis on prodrug-converting enzymes, prodrugs and drugs.

Breast Cancer Biomarkers Based on Nipple and Fine Needle Aspirates

National Research Council Canada - National Science Library

Russo, Irma H

2005-01-01

... of the cytological normal breast epithelium of women at high risk for breast cancer. This signature will serve as an intermediate biomarker for evaluating the response of the breast to novel chemopreventive agents...

Innovative agents in cancer prevention.

Science.gov (United States)

Manson, Margaret M; Farmer, Peter B; Gescher, Andreas; Steward, William P

2005-01-01

There are many facets to cancer prevention: a good diet, weight control and physical activity, a healthy environment, avoidance of carcinogens such as those in tobacco smoke, and screening of populations at risk to allow early detection. But there is also the possibility of using drugs or naturally occurring compounds to prevent initiation of, or to suppress, tumour growth. Only a few such agents have been used to date in the clinic with any success, and these include non-steroidal anti-inflammatory drugs for colon, finasteride for prostate and tamoxifen or raloxifene for breast tumours. An ideal chemopreventive agent would restore normal growth control to a preneoplastic or cancerous cell population by modifying aberrant signalling pathways or inducing apoptosis (or both) in cells beyond repair. Characteristics for such an agent include selectivity for damaged or transformed cells, good bioavailability and more than one mechanism of action to foil redundancy or crosstalk in signalling pathways. As more research effort is being targeted towards this area, the distinction between chemotherapeutic and chemopreventive agents is blurring. Chemotherapeutic drugs are now being designed to target over- or under-active signalling molecules within cancer cells, a philosophy which is just as relevant in chemoprevention. Development of dietary agents is particularly attractive because of our long-standing exposure to them, their relative lack of toxicity, and encouraging indications from epidemiology. The carcinogenic process relies on the cell's ability to proliferate abnormally, evade apoptosis, induce angiogenesis and metastasise to distant sites. In vitro studies with a number of different diet-derived compounds suggest that there are molecules capable of modulating each of these aspects of tumour growth. However, on the negative side many of them have rather poor bioavailability. The challenge is to uncover their multiple mechanisms of action in order to predict their

New Strategy for Prostate Cancer Prevention Based on Selenium Suppression of Androgen Receptor Signaling

Science.gov (United States)

2010-04-01

combination in prostate cancer chemoprevention. Emodin is a phytochemical that has been shown to induce AR degradation (18). We hypothesize that the...Since the induction of PSA screening , the majority of the prostate cancers diagnosed are asymptomatic, early-stage, small volume diseases. Current

A formulation of pancreatic pro-enzymes provides potent anti-tumour efficacy: a pilot study focused on pancreatic and ovarian cancer.

Science.gov (United States)

Perán, Macarena; López-Ruiz, Elena; García, María Ángel; Nadaraia-Hoke, Shorena; Brandt, Ralf; Marchal, Juan A; Kenyon, Julian

2017-10-25

Proteolytic enzymes have shown efficacy in cancer therapy. We present a combination of the two pro-enzymes Trypsinogen and Chymotrypsinogen A with potent in vitro and in vivo anti-tumour efficacy. A synergetic anti-tumour effect for Trypsinogen and Chymotrypsinogen A was determined at a ratio 1:6 (named PRP) using 24 human cancer cell lines. The antiangiogenic effect of PRP was analysed by matrigel-based tube formation and by fibrous capsule formation assays. Furthermore, cell invasion and wound healing assays together with qRT-PCR determination of epithelial-to-mesenchymal transition (EMT) markers were performed on human cancer cells treated with PRP. Additionally, in vivo pharmacokinetic studies were implemented and the PRP's anti-tumour efficacy was explored against orthotopic pancreatic and ovarian cancer tumours. PRP formulation was proven to inhibit in vitro angiogenesis, tumour growth, cancer cell migration and invasiveness; and to be an effective and well tolerated in vivo anti-tumour treatment. Finally, the clinical efficacy of a suppository formulation containing both pancreatic pro-enzymes in the context of a UK Pharmaceuticals Special Scheme was evaluated in advanced cancer patients. Consequently, PRP could have relevant oncological clinical applications for the treatment of advanced or metastatic pancreatic adenocarcinoma and advanced epithelial ovarian cancer.

Grapefruit and its biomedical, antigenotoxic and chemopreventive properties.

Science.gov (United States)

Cristóbal-Luna, José Melesio; Álvarez-González, Isela; Madrigal-Bujaidar, Eduardo; Chamorro-Cevallos, Germán

2018-02-01

Grapefruit (Citrus paradisi Mcfad) is a perenifolium tree 5-6 m high with a fruit of about 15 cm in diameter, protected by the peel we can find about 11-14 segments (carpels), each of which is surrounded by a membrane and each containing the juice sacs, as well as the seeds. The fruit is made up of numerous compounds, and is known to have nutritive value because of the presence of various vitamins and minerals, among other chemicals. The fruit is also used in the field of gastronomy. Information has been accumulated regarding the participation of the fruit structures in a variety of biomedical, antigenotoxic and chemopreventive effects, surely related with the presence of the numerous chemicals that have been determined to constitute the fruit. Such studies have been carried out in different in vitro and in vivo experimental models, and in a few human assays. The information published so far has shown interesting results, therefore, the aims of the present review are to initially examine the main characteristics of the fruit, followed by systematization of the acquired knowledge concerning the biomedical, antigenotoxic and chemopreventive effects produced by the three main structures of the fruit: peel, seed, and pulp. Copyright © 2018 Elsevier Ltd. All rights reserved.

Genotype of metabolic enzymes and the benefit of tamoxifen in postmenopausal breast cancer patients

International Nuclear Information System (INIS)

Wegman, Pia; Vainikka, Linda; Stål, Olle; Nordenskjöld, Bo; Skoog, Lambert; Rutqvist, Lars-Erik; Wingren, Sten

2005-01-01

Tamoxifen is widely used as endocrine therapy for oestrogen-receptor-positive breast cancer. However, many of these patients experience recurrence despite tamoxifen therapy by incompletely understood mechanisms. In the present report we propose that tamoxifen resistance may be due to differences in activity of metabolic enzymes as a result of genetic polymorphism. Cytochrome P450 2D6 (CYP2D6) and sulfotransferase 1A1 (SULT1A1) are polymorphic and are involved in the metabolism of tamoxifen. The CYP2D6*4 and SULT1A1*2 genotypes result in decreased enzyme activity. We therefore investigated the genotypes of CYP2D6 and SULT1A1 in 226 breast cancer patients participating in a trial of adjuvant tamoxifen treatment in order to validate the benefit from the therapy. The patients were genotyped using PCR followed by cleavage with restriction enzymes. Carriers of the CYP2D6*4 allele demonstrated a decreased risk of recurrence when treated with tamoxifen (relative risk = 0.28, 95% confidence interval = 0.11–0.74, P = 0.0089). A similar pattern was seen among the SULT1A1*1 homozygotes (relative risk = 0.48, 95% confidence interval = 0.21–1.12, P = 0.074). The combination of CYP2D6*4 and/or SULT1A1*1/*1 genotypes comprised 60% of the patients and showed a 62% decreased risk of distant recurrence with tamoxifen (relative risk = 0.38, 95% confidence interval = 0.19–0.74, P = 0.0041). The present study suggests that genotype of metabolic enzymes might be useful as a guide for adjuvant endocrine treatment of postmenopausal breast cancer patients. However, results are in contradiction to prior hypotheses and the present sample size is relatively small. Findings therefore need to be confirmed in a larger cohort

Skin Cancer Chemoprevention by Silibinin: Mechanisms and Efficacy | Division of Cancer Prevention

Science.gov (United States)

Basal cell carcinoma (BCC), a non-melanoma skin cancer (NMSC) type, is a major health problem in the United States (US); annual BCC incidences alone are higher than all other cancer incidences combined (1.67 million/year). Most BCC cases are curable by surgery/radiation, but these can be painful and highly disfiguring and are not viable treatment options for BCC patients with

Prevention of Post-Radiotherapy Failure in Prostate Cancer by Vitamin D

National Research Council Canada - National Science Library

Vijayakumar, Srinivasan

2005-01-01

.... We propose to have prostate cancer patients who have already undergone radiation treatment take a non-toxic chemopreventive agent A SYNTHETIC FORM OF VITAMIN D, 1alpha-hydroxyvitamin D5 for two years...

Red Wine Polyphenols for Cancer Prevention

OpenAIRE

He, Shan; Sun, Cuirong; Pan, Yuanjiang

2008-01-01

Conventional cancer therapies, the second leading cause of death worldwide, result in serious side effects and, at best, merely extend the patient's lifespan by a few years. Searching for effective prevention is of high priority in both basic and clinical sciences. In recent decades natural products have been considered to be an important source of cancer chemopreventive agents. Red wine polyphenols, which consisted of various powerful antioxidants such as flavonoids and stilbenes, have been ...

Chemopreventive Effects of RXR-Selective Rexinoid Bexarotene on Intestinal Neoplasia of ApcMin/+ Mice

Directory of Open Access Journals (Sweden)

Naveena B. Janakiram

2012-02-01

Full Text Available Retinoid X receptor (RXR has been implicated in several neoplastic diseases. Previously, we have shown that RXR-α is downregulated in human and rodent colonic tumors, suggesting a potential target for colon cancer prevention (http://www.cancer.org/Cancer/ColonandRectumCancer/DetailedGuide/colorectal-cancer-key-statistics. Experiments were designed to assess the chemopreventive efficacy of the selective RXR agonist bexarotene for the suppression of intestinal tumorigenesis in ApcMin/+ mice. Before the efficacy studies, we determined that the maximal tolerated dose in C57BL/6J mice was less than 400 ppm. For the efficacy study, 6-week-old male and female C57BL/6J-ApcMin/+ mice (nine mice per group were fed diets containing 0, 30, and 60 ppm of bexarotene or 200 ppm of bexarotene for 80 days before intestinal tumors were evaluated. Dietary administration of 30 and 60 ppm of bexarotene suppressed the intestinal polyp formation by 38% (P < .015 and 60% (P < .0001 in males, respectively, and by 8.5% and 37% (P < .007 in females, respectively. Also, significant inhibition (50%–100% of colonic tumor formation was observed in both male and female mice with bexarotene treatment. Administration of 200 ppm of bexarotene showed significant suppression of tumor formation (66%, P < .0001; however, it had significant toxicity. Intestinal tumors of bexarotene-fed mice showed significantly reduced expression of proliferating cell nuclear antigen (60%, P < .0001, cyclin D1, and cyclooxygenase 2 and increased RXR-α messenger RNA and uptake of oleate (34%, P < .01. Also, bexarotene-fed mice showed dose-dependent suppression of serum triglycerides (25%–72%, P < .0001 and inflammatory cytokines.

Priorities for the primary prevention of breast cancer.

Science.gov (United States)

Colditz, Graham A; Bohlke, Kari

2014-01-01

Despite recent calls to intensify the search for new risk factors for breast cancer, acting on information that we already have could prevent thousands of cases each year. This article reviews breast cancer primary prevention strategies that are applicable to all women, discusses the underutilization of chemoprevention in high-risk women, highlights the additional advances that could be made by including young women in prevention efforts, and comments on how the molecular heterogeneity of breast cancer affects prevention research and strategies. © 2014 American Cancer Society.

Chemopreventive Effects of the p53-Modulating Agents CP-31398 and Prima-1 in Tobacco Carcinogen-Induced Lung Tumorigenesis in A/J Mice

Directory of Open Access Journals (Sweden)

Chinthalapally V. Rao

2013-09-01

Full Text Available Lung cancer is the leading cause of cancer deaths worldwide. Expression of the p53 tumor suppressor protein is frequently altered in tobacco-associated lung cancers. We studied chemopreventive effects of p53-modulating agents, namely, CP-31398 and Prima-1, on 4-(methylnitrosamino-1-(3-pyridyl-1-butanone (NNK-induced lung adenoma and adenocarcinoma formation in female A/J mice. Seven-week-old mice were treated with a single dose of NNK (10 µmol/mouse by intraperitoneal injection and, 3 weeks later, were randomized to mice fed a control diet or experimental diets containing 50 or 100 ppm CP-31398 or 150 or 300 ppm Prima-1 for either 17 weeks (10 mice/group or 34 weeks (15 mice/group to assess the efficacy against lung adenoma and adenocarcinoma. Dietary feeding of 50 or 100 ppm CP-31398 significantly suppressed (P < .0001 lung adenocarcinoma by 64% and 73%, respectively, after 17 weeks and by 47% and 56%, respectively, after 34 weeks. Similarly, 150 or 300 ppm Prima-1 significantly suppressed (P < .0001 lung adenocarcinoma formation by 56% and 62%, respectively, after 17 weeks and 39% and 56%, respectively, after 34 weeks. Importantly, these results suggest that both p53 modulators cause a delay in the progression of adenoma to adenocarcinoma. Immunohistochemical analysis of lung tumors from mice exposed to p53-modulating agents showed a significantly reduced tumor cell proliferation and increased accumulation of wild-type p53 in the nucleus. An increase in p21- and apoptotic-positive cells was also observed in lung tumors of mice exposed to p53-modulating agents. These results support a chemopreventive role of p53-modulating agents in tobacco carcinogen-induced lung adenocarcinoma formation.

Quantitation of chemopreventive synergism between (-)-epigallocatechin-3-gallate and curcumin in normal, premalignant and malignant human oral epithelial cells.

Science.gov (United States)

Khafif, A; Schantz, S P; Chou, T C; Edelstein, D; Sacks, P G

1998-03-01

An in vitro model for oral cancer was used to examine the growth inhibitory effects of chemopreventive agents when used singly and in combination. The model consists of primary cultures of normal oral epithelial cells, newly established cell lines derived from dysplastic leukoplakia and squamous cell carcinoma. Two naturally occurring substances, (-)-epigallocatechin-3-gallate (EGCG) from green tea and curcumin from the spice turmeric were tested. Cells were treated singly and in combination and effects on growth determined in 5-day growth assays and by cell cycle analysis. Effective dose 50s and the combination index were calculated with the computerized Chou-Talalay method which is based on the median-effect principle. Agents were shown to differ in their inhibitory potency. EGCG was less effective with cell progression; the cancer cells were more resistant than normal or dysplastic cells. In contrast, curcumin was equally effective regardless of the cell type tested. Cell cycle analysis indicated that EGCG blocked cells in G1, whereas curcumin blocked cells in S/G2M. The combination of both agents showed synergistic interactions in growth inhibition and increased sigmoidicity (steepness) of the dose-effect curves, a response that was dose and cell type dependent. Combinations allowed for a dose reduction of 4.4-8.5-fold for EGCG and 2.2-2.8-fold for curcumin at ED50s as indicated by the dose reduction index (DRI). Even greater DRI values were observed above ED50 levels. Our results demonstrate that this model which includes normal, premalignant and malignant oral cells can be used to analyse the relative potential of various chemopreventive agents. Two such naturally-occurring agents, EGCG and curcumin, were noted to inhibit growth by different mechanisms, a factor which may account for their demonstrable interactive synergistic effect.

Effects of Brassicaceae Isothiocyanates on Prostate Cancer

Directory of Open Access Journals (Sweden)

Silvia Novío

2016-05-01

Full Text Available Despite the major progress made in the field of cancer biology, cancer is still one of the leading causes of mortality, and prostate cancer (PCa is one of the most encountered malignancies among men. The effective management of this disease requires developing better anticancer agents with greater efficacy and fewer side effects. Nature is a large source for the development of chemotherapeutic agents, with more than 50% of current anticancer drugs being of natural origin. Isothiocyanates (ITCs are degradation products from glucosinolates that are present in members of the family Brassicaceae. Although they are known for a variety of therapeutic effects, including antioxidant, immunostimulatory, anti-inflammatory, antiviral and antibacterial properties, nowadays, cell line and animal studies have additionally indicated the chemopreventive action without causing toxic side effects of ITCs. In this way, they can induce cell cycle arrest, activate apoptosis pathways, increase the sensitivity of resistant PCa to available chemodrugs, modulate epigenetic changes and downregulate activated signaling pathways, resulting in the inhibition of cell proliferation, progression and invasion-metastasis. The present review summarizes the chemopreventive role of ITCs with a particular emphasis on specific molecular targets and epigenetic alterations in in vitro and in vivo cancer animal models.

ACTOplus Met XR in Treating Patients With Stage I-IV Oral Cavity or Oropharynx Cancer Undergoing Definitive Treatment | Division of Cancer Prevention

Science.gov (United States)

This randomized phase IIb trial studies how well ACTOplus met XR works in treating in patients with stage I-IV oral cavity or oropharynx cancer that are undergoing definitive treatment. Chemoprevention is the use of drugs to keep oral cavity or oropharynx cancer from forming or coming back. The use of ACTOplus met XR may slow disease progression in patients with oral cavity or

The Role of Redox-Regulating Enzymes in Inoperable Breast Cancers Treated with Neoadjuvant Chemotherapy

Directory of Open Access Journals (Sweden)

Nelli Roininen

2017-01-01

Full Text Available Although validated predictive factors for breast cancer chemoresistance are scarce, there is emerging evidence that the induction of certain redox-regulating enzymes may contribute to a poor chemotherapy effect. We investigated the possible association between chemoresistance and cellular redox state regulation in patients undergoing neoadjuvant chemotherapy (NACT for breast cancer. In total, 53 women with primarily inoperable or inflammatory breast cancer who were treated with NACT were included in the study. Pre-NACT core needle biopsies and postoperative tumor samples were immunohistochemically stained for nuclear factor erythroid 2-related factor 2 (Nrf2, Kelch-like ECH-associated protein 1 (Keap1, thioredoxin (Trx, and peroxiredoxin I (Prx I. The expression of all studied markers increased during NACT. Higher pre-NACT nuclear Prx I expression predicted smaller size of a resected tumor (p=0.00052; r=−0.550, and higher pre-NACT cytoplasmic Prx I expression predicted a lower amount of evacuated nodal metastasis (p=0.0024; r=−0.472. Pre-NACT nuclear Trx expression and pre-NACT nuclear Keap1 expression had only a minor prognostic significance as separate factors, but when they were combined, low expression for both antibodies before NACT predicted dismal disease-free survival (log-rank p=0.0030. Our results suggest that redox-regulating enzymes may serve as potential prognostic factors in primarily inoperable breast cancer patients.

Prevention of ovarian cancer.

Science.gov (United States)

Hanna, Louise; Adams, Malcolm

2006-04-01

Ovarian cancer is the leading cause of death from gynaecological malignancy. The incidence is high in the Western world. The incidence of ovarian cancer is reduced by pregnancy, lactation, the oral contraceptive pill and tubal ligation. Lifestyle factors are important in the aetiology of ovarian cancer and current evidence suggests the risk can be reduced by eating a diet rich in fruit and vegetables, taking regular exercise, avoiding smoking, avoiding being overweight and avoiding long-term use of hormonal replacement therapy (HRT). Familial ovarian cancer is responsible for about 10% of ovarian cancer cases. Strategies available to high-risk women include screening (covered elsewhere) and prophylactic salpingo-oophorectomy. The precise role of chemoprevention for high-risk women in the form of the oral contraceptive pill is unclear.

Effect of a vegan diet on biomarkers of chemoprevention in females

NARCIS (Netherlands)

Verhagen, H.; Rauma, A.L.; Törrönen, R.; Vogel, N. de; Bruijntjes-Rozier, G.C.D.M.; Dreve, M.A.; Bogaards, J.J.P.; Mykkänen, H.

1996-01-01

1. In order to study the potential beneficial effects of a vegan diet, a cross-sectional study was performed and several biomarkers of chemoprevention were measured in a population of female 'living food' eaters ('vegans'; n = 20) vs matched omnivorous controls (n = 20). 2. White blood cells

Nutrients, Foods, and Colorectal Cancer Prevention

OpenAIRE

Song, Mingyang; Garrett, Wendy S.; Chan, Andrew T.

2015-01-01

Diet has an important role in the development of colorectal cancer. In the past few decades, findings from extensive epidemiologic and experimental investigation have linked consumption of several foods and nutrients to the risk of colorectal neoplasia. Calcium, fiber, milk, and whole grain have been associated with a lower risk of colorectal cancer, and red meat and processed meat with an increased risk. There is substantial evidence for the potential chemopreventive effects of vitamin D, fo...

Dietary factors and epigenetic regulation for prostate cancer prevention.

Science.gov (United States)

Ho, Emily; Beaver, Laura M; Williams, David E; Dashwood, Roderick H

2011-11-01

The role of epigenetic alterations in various human chronic diseases has gained increasing attention and has resulted in a paradigm shift in our understanding of disease susceptibility. In the field of cancer research, e.g., genetic abnormalities/mutations historically were viewed as primary underlying causes; however, epigenetic mechanisms that alter gene expression without affecting DNA sequence are now recognized as being of equal or greater importance for oncogenesis. Methylation of DNA, modification of histones, and interfering microRNA (miRNA) collectively represent a cadre of epigenetic elements dysregulated in cancer. Targeting the epigenome with compounds that modulate DNA methylation, histone marks, and miRNA profiles represents an evolving strategy for cancer chemoprevention, and these approaches are starting to show promise in human clinical trials. Essential micronutrients such as folate, vitamin B-12, selenium, and zinc as well as the dietary phytochemicals sulforaphane, tea polyphenols, curcumin, and allyl sulfur compounds are among a growing list of agents that affect epigenetic events as novel mechanisms of chemoprevention. To illustrate these concepts, the current review highlights the interactions among nutrients, epigenetics, and prostate cancer susceptibility. In particular, we focus on epigenetic dysregulation and the impact of specific nutrients and food components on DNA methylation and histone modifications that can alter gene expression and influence prostate cancer progression.

The selective estrogen receptor modulators in breast cancer prevention.

Science.gov (United States)

Li, Fangxuan; Dou, Jinli; Wei, Lijuan; Li, Shixia; Liu, Juntian

2016-05-01

Persistently increased blood levels of estrogens are associated with an increased risk of breast cancer. Selective estrogen receptor modulators (SERMs) are a class of compounds that act on the estrogen receptor (ER). Several clinical trials have demonstrated the effectiveness of its prophylactic administration. Incidence of invasive ER-positive breast cancer was reduced by SERMs treatment, especially for those women with high risk of developing breast cancer. In this study, we reviewed the clinical application of SERMs in breast cancer prevention. To date, four prospective randomized clinical trials had been performed to test the efficacy of tamoxifen for this purpose. Concerning on the benefit and cost of tamoxifen, various studies from different countries demonstrated that chemoprevention with tamoxifen seemed to be cost-effective for women with a high risk of invasive breast cancer. Based above, tamoxifen was approved for breast cancer prevention by the US Food and Drug Administration in 1998. Raloxifene was also approved for postmenopausal women in 2007 for breast cancer prevention which reduces the risk of invasive breast cancer with a lower risk of unwanted stimulation of endometrium. Thus, raloxifene is considered to have a better clinical possesses as prophylactic agent. Several other agents, such as arzoxifene and lasofoxifene, are currently being investigated in clinic. The American Society of Clinical Oncology and National Comprehensive Cancer Network had published guidelines on breast cancer chemoprevention by SERMs. However, use of tamoxifen and raloxifene for primary breast cancer prevention was still low. A broader educational effort is needed to alert women and primary care physicians that SERMs are available to reduce breast cancer risk.

Compounds from the Fruits of the Popular European Medicinal Plant Vitex agnus-castus in Chemoprevention via NADP(H:Quinone Oxidoreductase Type 1 Induction

Directory of Open Access Journals (Sweden)

Shenghong Li

2013-01-01

Full Text Available As part of our continuing efforts in the search for potential biologically active compounds from medicinal plants, we have isolated 18 compounds including two novel nitrogen containing diterpenes from extracts of the fruits of Vitex agnus-castus. These isolates, along with our previously obtained novel compound vitexlactam A (1, were evaluated for potential biological effects, including cancer chemoprevention. Chemically, the nitrogenous isolates were found to be two labdane diterpene alkaloids, each containing an α, β-unsaturated γ-lactam moiety. Structurally, they were elucidated to be 9α-hydroxy-13(14-labden-16,15-amide (2 and 6β-acetoxy-9α-hydroxy-13(14-labden-15,16-amide (3, which were named vitexlactams B and C, respectively. The 15 known isolates were identified as vitexilactone (4, rotundifuran (5, 8-epi-manoyl oxide (6, vitetrifolin D (7, spathulenol (8, cis-dihydro-dehydro-diconiferylalcohol-9-O-β-D-glucoside (9, luteolin-7-O-glucoside (10, 5-hydroxy-3,6,7,4′-tetramethoxyflavone (11, casticin (12, artemetin (13, aucubin (14, agnuside (15, β-sitosterol (16, p-hydroxybenzoic acid (17, and p-hydroxybenzoic acid glucose ester (18. All compound structures were determined/identified on the basis of 1D and/or 2D NMR and mass spectrometry techniques. Compounds 6, 8, 9, and 18 were reported from a Vitex spieces for the first time. The cancer chemopreventive potentials of these isolates were evaluated for NADP(H:quinone oxidoreductase type 1 (QR1 induction activity. Compound 7 demonstrated promising QR1 induction effect, while the new compound vitexlactam (3 was only slightly active.

Compounds from the Fruits of the Popular European Medicinal Plant Vitex agnus-castus in Chemoprevention via NADP(H):Quinone Oxidoreductase Type 1 Induction.

Science.gov (United States)

Li, Shenghong; Qiu, Shengxiang; Yao, Ping; Sun, Handong; Fong, Harry H S; Zhang, Hongjie

2013-01-01

As part of our continuing efforts in the search for potential biologically active compounds from medicinal plants, we have isolated 18 compounds including two novel nitrogen containing diterpenes from extracts of the fruits of Vitex agnus-castus. These isolates, along with our previously obtained novel compound vitexlactam A (1), were evaluated for potential biological effects, including cancer chemoprevention. Chemically, the nitrogenous isolates were found to be two labdane diterpene alkaloids, each containing an α , β -unsaturated γ -lactam moiety. Structurally, they were elucidated to be 9 α -hydroxy-13(14)-labden-16,15-amide (2) and 6 β -acetoxy-9 α -hydroxy-13(14)-labden-15,16-amide (3), which were named vitexlactams B and C, respectively. The 15 known isolates were identified as vitexilactone (4), rotundifuran (5), 8-epi-manoyl oxide (6), vitetrifolin D (7), spathulenol (8), cis-dihydro-dehydro-diconiferylalcohol-9-O- β -D-glucoside (9), luteolin-7-O-glucoside (10), 5-hydroxy-3,6,7,4'-tetramethoxyflavone (11), casticin (12), artemetin (13), aucubin (14), agnuside (15), β -sitosterol (16), p-hydroxybenzoic acid (17), and p-hydroxybenzoic acid glucose ester (18). All compound structures were determined/identified on the basis of 1D and/or 2D NMR and mass spectrometry techniques. Compounds 6, 8, 9, and 18 were reported from a Vitex spieces for the first time. The cancer chemopreventive potentials of these isolates were evaluated for NADP(H):quinone oxidoreductase type 1 (QR1) induction activity. Compound 7 demonstrated promising QR1 induction effect, while the new compound vitexlactam (3) was only slightly active.

DUOX enzyme activity promotes AKT signalling in prostate cancer cells.

Science.gov (United States)

Pettigrew, Christopher A; Clerkin, John S; Cotter, Thomas G

2012-12-01

Reactive oxygen species (ROS) and oxidative stress are related to tumour progression, and high levels of ROS have been observed in prostate tumours compared to normal prostate. ROS can positively influence AKT signalling and thereby promote cell survival. The aim of this project was to establish whether the ROS generated in prostate cancer cells positively regulate AKT signalling and enable resistance to apoptotic stimuli. In PC3 cells, dual oxidase (DUOX) enzymes actively generate ROS, which inactivate phosphatases, thereby maintaining AKT phosphorylation. Inhibition of DUOX by diphenylene iodium (DPI), intracellular calcium chelation and small-interfering RNA (siRNA) resulted in lower ROS levels, lower AKT and glycogen synthase kinase 3β (GSK3β) phosphorylation, as well as reduced cell viability and increased susceptibility to apoptosis stimulating fragment (FAS) induced apoptosis. This report shows that ROS levels in PC3 cells are constitutively maintained by DUOX enzymes, and these ROS positively regulate AKT signalling through inactivating phosphatases, leading to increased resistance to apoptosis.

Norathyriol Suppresses Skin Cancers Induced by Solar Ultraviolet Radiation by Targeting ERK Kinases

Energy Technology Data Exchange (ETDEWEB)

Li, Jixia; Malakhova, Margarita; Mottamal, Madhusoodanan; Reddy, Kanamata; Kurinov, Igor; Carper, Andria; Langfald, Alyssa; Oi, Naomi; Kim, Myoung Ok; Zhu, Feng; Sosa, Carlos P.; Zhou, Keyuan; Bode, Ann M.; Dong, Zigang (Cornell); (Guangdong); (UMM)

2012-06-27

Ultraviolet (UV) irradiation is the leading factor in the development of skin cancer, prompting great interest in chemopreventive agents for this disease. In this study, we report the discovery of norathyriol, a plant-derived chemopreventive compound identified through an in silico virtual screening of the Chinese Medicine Library. Norathyriol is a metabolite of mangiferin found in mango, Hypericum elegans, and Tripterospermum lanceolatum and is known to have anticancer activity. Mechanistic investigations determined that norathyriol acted as an inhibitor of extracellular signal-regulated kinase (ERK)1/2 activity to attenuate UVB-induced phosphorylation in mitogen-activated protein kinases signaling cascades. We confirmed the direct and specific binding of norathyriol with ERK2 through a cocrystal structural analysis. The xanthone moiety in norathyriol acted as an adenine mimetic to anchor the compound by hydrogen bonds to the hinge region of the protein ATP-binding site on ERK2. Norathyriol inhibited in vitro cell growth in mouse skin epidermal JB6 P+ cells at the level of G{sub 2}-M phase arrest. In mouse skin tumorigenesis assays, norathyriol significantly suppressed solar UV-induced skin carcinogenesis. Further analysis indicated that norathyriol mediates its chemopreventive activity by inhibiting the ERK-dependent activity of transcriptional factors AP-1 and NF-{kappa}B during UV-induced skin carcinogenesis. Taken together, our results identify norathyriol as a safe new chemopreventive agent that is highly effective against development of UV-induced skin cancer.

Effect of selenium-saturated bovine lactoferrin (Se-bLF) on antioxidant enzyme activities in human gut epithelial cells under oxidative stress.

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Burrow, Hannah; Kanwar, Rupinder K; Mahidhara, Ganesh; Kanwar, Jagat R

2011-10-01

Cancer and many chronic inflammatory diseases are associated with increased amounts of reactive oxygen species (ROS). The potential cellular and tissue damage created by ROS has significant impact on many disease and cancer states and natural therapeutics are becoming essential in regulating altered redox states. We have shown recently that iron content is a critical determinant in the antitumour activity of bovine milk lactoferrin (bLF). We found that 100% iron-saturated bLF (Fe-bLF) acts as a potent natural adjuvant and fortifying agent for augmenting cancer chemotherapy and thus has a broad utility in the treatment of cancer. Furthermore, we also studied the effects of iron saturated bLF's ability as an antioxidant in the human epithelial colon cancer cell line HT29, giving insights into the potential of bLF in its different states. Thus, metal saturated bLF could be implemented as anti-cancer neutraceutical. In this regard, we have recently been able to prepare a selenium (Se) saturated form of bLF, being up to 98% saturated. Therefore, the objectives of this study were to determine how oxidative stress induced by hydrogen peroxide (H2O2) alters antioxidant enzyme activity within HT29 epithelial colon cancer cells, and observe changes in this activity by treatments with different antioxidants ascorbic acid (AA), Apo (iron free)-bLF and selenium (Se)-bLF. The states of all antioxidant enzymes (glutathione peroxidase (GPx), glutathione reductase (GR), glutathione- s-transferase (GsT), catalase and superoxide dismutase (SOD)) demonstrated high levels within untreated HT29 cells compared to the majority of other treatments being used, even prior to H2O2 exposure. All enzymes showed significant alterations in activity when cells were treated with antioxidants AA, Apo-bLF or Se-bLF, with and/or without H2O2 exposure. Obvious indications that the Se content of the bLF potentially interacted with the glutathione (GSH)/GPx/GR/GsT associated redox system could be

Biological Basis for Chemoprevention of Ovarian Cancer

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2006-10-01

Concealing Clothing” Sukru Hatun, Omer Islam, Filiz Cizmecioglu, Bulent Kara, Kadir Babaoglu, Fatma Berk,and Ayse Sevim Go¨ kalp J. Nutr. 135: 218–222...to studies in ovarian caner , analyses of the relationship between the short AR CAG repeat length polymorphism and prostate cancer risk also have...pregnant, months of OC use, BMI, tubal ligation, family history of breast or ovarian caner in a first degree relative, waist-to-hip ratio 23 Table 6

Dietary intake of total polyphenol and polyphenol classes and the risk of colorectal cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort

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Zamora-Ros, Raul; Cayssials, Valerie; Jenab, Mazda

2018-01-01

Polyphenols may play a chemopreventive role in colorectal cancer (CRC); however, epidemiological evidence supporting a role for intake of individual polyphenol classes, other than flavonoids is insufficient. We evaluated the association between dietary intakes of total and individual classes and ...

Epigenetic potential of resveratrol and analogs in preclinical models of prostate cancer

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Prostate cancer is affected by lifestyle, particularly diet. Dietary polyphenols such as resveratrol possess anticancer properties and, therefore, chemopreventive and therapeutic potentials. Resveratrol has pleiotropic effect exerting its biological activity through multiple pathways and targets ass...

Polyphenols in Food: Cancer Prevention and Apoptosis Induction.

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Sharma, Ashita; Kaur, Mandeep; Katnoria, Jatinder Kaur; Nagpal, Avinash Kaur

2017-10-06

Polyphenols are group of water-soluble organic compounds, mainly of natural origin. The compounds having about 5-7 aromatic rings and more than 12 phenolic hydroxyl groups are classified as polyphenols. These are the antioxidants which protect the body from oxidative damage. In plants, they are the secondary metabolites produced as a defense mechanism against stress factors. Antioxidant property of polyphenols is suggested to provide protection against many diseases associated with reactive oxygen species (ROS), including cancer. Various studies carried out across the world have suggested that polyphenols can inhibit the tumor generation, induce apoptosis in cancer cells and interfere in progression of tumors. This group of wonder compounds is present in surplus in natural plants and food products. Intake of polyphenols through diet can scavenge ROS and thus can help in cancer prevention. The plant derived products can also be used along with conventional chemotherapy to enhance the chemopreventive effects. The present review focuses on various in vitro and in vivo studies carried out to assess the anti-carcinogenic potential of polyphenols present in our food. Also, the pathways involved in cancer chemopreventive effects of various subclasses (flavonoids, lignans, stilbenes and phenolic acids) of polyphenols are discussed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

NOSH-aspirin (NBS-1120), a novel nitric oxide- and hydrogen sulfide-releasing hybrid has enhanced chemo-preventive properties compared to aspirin, is gastrointestinal safe with all the classic therapeutic indications

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Kodela, Ravinder; Chattopadhyay, Mitali; Velázquez-Martínez, Carlos A.; Kashfi, Khosrow

2015-01-01

Aspirin is chemopreventive; however, side effects preclude its long-term use. NOSH-aspirin (NBS-1120), a novel hybrid that releases nitric oxide and hydrogen sulfide, was designed to be a safer alternative. Here we compare the gastrointestinal safety, anti-inflammatory, analgesic, antipyretic, anti-platelet, and chemopreventive properties of aspirin and NBS-1120 administered orally to rats at equimolar doses. Gastrointestinal safety: 6h post-administration, the number and size of hemorrhagic lesions in stomachs were counted; tissue samples were frozen for PGE2, SOD, and MDA determination. Anti-inflammatory: 1h after drug administration, the volume of carrageenan-induced rat paw edemas was measured for 5h. Anti-pyretic: fever was induced by LPS (ip) an hour before administration of the test drugs, core body temperature was measured hourly for 5h. Analgesic: time-dependent analgesic effects were evaluated by carrageenan-induced hyperalgesia. Antiplatelet: anti-aggregatory effects were studied on collagen-induced platelet aggregation of human platelet-rich plasma. Chemoprevention: Nude mice were gavaged daily for 25 days with vehicle, aspirin or NBS-1120. After one week, each mouse was inoculated subcutaneously in the right flank with HT-29 human colon cancer cells. Both agents reduced PGE2 levels in stomach tissue; however, NBS-1120 did not cause any stomach ulcers, whereas aspirin caused significant bleeding. Lipid peroxidation induced by aspirin was higher than that exerted by NBS-1120. SOD activity was significantly inhibited by aspirin but increased by NBS-1120. Both agents showed similar anti-inflammatory, analgesic, anti-pyretic, and anti-platelet activities. Aspirin increased plasma TNFα more than NBS-1120-treated animals. NBS-1120 was better than aspirin as a chemopreventive agent; it dose-dependently inhibited tumor growth and tumor mass. PMID:26394025

Non-classical mechanisms of transcriptional regulation by the vitamin D receptor: insights into calcium homeostasis, immune system regulation and cancer chemoprevention.

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Dimitrov, Vassil; Salehi-Tabar, Reyhaneh; An, Beum-Soo; White, John H

2014-10-01

Hormonal 1,25-dihydroxyvitamin D [1,25(OH)2D] signals through the nuclear vitamin D receptor (VDR), a ligand-regulated transcription factor. Gene expression profiling studies have revealed that 1,25(OH)2D signaling through the VDR can lead to activation or repression of target gene transcription in roughly equal proportions. Classically, transcriptional regulation by the VDR, similar to other nuclear receptors, has been characterized by its capacity to recognize high affinity cognate vitamin D response elements (VDREs), located in the regulatory regions of target genes. Several biochemical studies revealed that the VDRE-bound receptor recruits a series of coregulatory proteins, leading to transactivation of adjacent target genes. However, genome-wide and other analyses of VDR binding have revealed that a subset of VDR binding sites does not contain VDREs, and that VDREs are not associated with transcriptionally repressed VDR target genes. Work over the last ∼20 years and in particular recent findings have revealed a diverse array of mechanisms by which VDR can form complexes with several other classes of transcriptional activators, leading to repression of gene transcription. Moreover, these efforts have led to several insights into the molecular basis for the physiological regulation of calcium homeostasis, immune system function and cancer chemoprevention by 1,25(OH)2D/VDR signaling. This article is part of a Special Issue entitled '16th Vitamin D Workshop'. Copyright © 2013 Elsevier Ltd. All rights reserved.

Pancreatic enzyme supplementation after gastrectomy for gastric cancer: a randomized controlled trial.

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Catarci, Marco; Berlanda, Manuele; Grassi, Giovanni Battista; Masedu, Francesco; Guadagni, Stefano

2018-05-01

Gastrectomy for gastric cancer is a significant cause of secondary exocrine pancreatic insufficiency. Pancreatic enzyme replacement therapy may influence nutritional status and quality of life after gastrectomy, but the pertinent clinical research to date remains controversial. A randomized controlled trial to test this hypothesis was carried out. After gastrectomy, 43 patients with gastric cancer were randomly assigned to a normal diet (Normal-d; n = 21) or to a pancreatic enzyme supplementation diet (PES-d; n = 22) and were followed up during a 12-month period, assessing nutritional status and quality of life through body mass index (BMI), instant nutritional assessment (INA) class status, serum pre-albumin (SPA) values, and GastroiIntestinal Quality of Life Index (GIQLI). BMI was not significantly influenced by the type of diet; INA class status was significantly improved in the PES-d arm, particularly during the first 3 months after gastrectomy; SPA levels increased in both arms at 6 months after gastrectomy, reaching significantly higher values in the PES-d arm at 12 months. GIQLI was not significantly influenced by the type of diet throughout the follow-up period; however, this index significantly improved in the PES-d arm between the first and third month after gastrectomy. PES-d improves nutritional status and quality of life after gastrectomy for gastric cancer, particularly within 3 months from the operation. A larger, multicenter trial is necessary to address the potential influence of several confounding variables such as disease stage and adjuvant treatments.

Mouse Models for Studying Oral Cancer: Impact in the Era of Cancer Immunotherapy.

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Luo, J J; Young, C D; Zhou, H M; Wang, X J

2018-04-01

Model systems for oral cancer research have progressed from tumor epithelial cell cultures to in vivo systems that mimic oral cancer genetics, pathological characteristics, and tumor-stroma interactions of oral cancer patients. In the era of cancer immunotherapy, it is imperative to use model systems to test oral cancer prevention and therapeutic interventions in the presence of an immune system and to discover mechanisms of stromal contributions to oral cancer carcinogenesis. Here, we review in vivo mouse model systems commonly used for studying oral cancer and discuss the impact these models are having in advancing basic mechanisms, chemoprevention, and therapeutic intervention of oral cancer while highlighting recent discoveries concerning the role of immune cells in oral cancer. Improvements to in vivo model systems that highly recapitulate human oral cancer hold the key to identifying features of oral cancer initiation, progression, and invasion as well as molecular and cellular targets for prevention, therapeutic response, and immunotherapy development.

Adlay (薏苡 yì yĭ; “soft-shelled job's tears”; the seeds of Coix lachryma-jobi L. var. ma-yuen Stapf is a Potential Cancer Chemopreventive Agent toward Multistage Carcinogenesis Processes

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Ching-Chuan Kuo, Ph.D.

2012-10-01

Full Text Available Adlay (薏苡 yì yĭ; “soft-shelled job’s tears”, the seeds of Coix lachryma-jobi L. var. ma-yuen Stapf is a grass crop that has long been used in traditional Chinese medicine (TCM and as a nourishing food in China for the treatment of warts, chapped skin, rheumatism, neuralgia, inflammatory, and neoplastic diseases. In addition, adlay also has been said to have stomachic, diuretic, antipholgistic, anodynic, and antispasmodic effects. Carcinogenesis is a multistage process that begins with exposure of viruses or chemicals that are found in the environment. Chemoprevention refers to the use of natural or synthetic, non-toxic chemical substances to reverse, repress, or prevent carcinogenesis. In this review, we summarize recent research attempting to study the chemopreventive blocking and suppressing potential of adlay and its active components in scavenging electrophiles and reactive oxygen species, antimutagenicity, enhancing Nrf2-mediated detoxification and antioxidant effect, altering carcinogen metabolism, suppressing proliferation, decreasing inflammation, and enhancing antitumor immunity. In addition, several active components with diverse chemopreventive properties have been also mentioned in this review article.

Topical Treatment with Diclofenac, Calcipotriol (Vitamin-D3 Analog) and Difluoromethylornithine (DFMO) Does Not Prevent Nonmelanoma Skin Cancer in Mice

DEFF Research Database (Denmark)

Pommergaard, H C; Burcharth, J; Rosenberg, J

2013-01-01

Nonmelanoma skin cancer is a common cancer type with increasing incidence. The purpose of this study was to evaluate topical application of diclofenac, calcipotriol, and difluoromethylornithine as chemoprevention in a mouse model of ultraviolet light-induced skin tumors, since these agents have...

Prognostic Value of Malic Enzyme and ATP-Citrate Lyase in Non-Small Cell Lung Cancer of the Young and the Elderly.

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Agnes Csanadi

Full Text Available Lung cancer is the leading cause of death among malignancies worldwide. Understanding its biology is therefore of pivotal importance to improve patient's prognosis. In contrast to non-neoplastic tissues, cancer cells utilize glucose mainly for production of basic cellular modules '(i.e. nucleotides, aminoacids, fatty acids. In cancer, Malic enzyme (ME and ATP-citrate lyase (ACLY are key enzymes linking aerobic glycolysis and fatty acid synthesis and may therefore be of biological and prognostic significance in non-small cell lung cancer (NSCLC.ME and ACLY expression was analyzed in 258 NSCLC in correlation with clinico-pathological parameters including patient's survival.Though, overall expression of both enzymes correlated positively, ACLY was associated with local tumor stage, whereas ME correlated with occurrence of mediastinal lymph node metastases. Young patients overexpressing ACLY and/or ME had a significantly longer overall survival. This proved to be an independent prognostic factor. This contrasts older NSCLC patients, in whom overexpression of ACLY and/or ME appears to predict the opposite.In NSCLC, ME and ACLY show different enzyme expressions relating to local and mediastinal spread. Most important, we detected an inverse prognostic impact of ACLY and/or ME overexpression in young and elderly patients. It can therefore be expected, that treatment of NSCLC especially, if targeting metabolic pathways, requires different strategies in different age groups.

Application Instructions | Division of Cancer Prevention

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This is NOT a grant application - if successful, funds will not be transferred to your institution to support your project. Rather, this is an application to access the scientific capabilities and resources of the NCI with the goal of moving promising cancer chemopreventive agents into clinical testing. If successful, you will partner with the NCI in developing a drug

Chemopreventive and Anticancer Activities of Allium victorialis var. platyphyllum Extracts.

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Kim, Hyun-Jeong; Park, Min Jeong; Park, Hee-Juhn; Chung, Won-Yoon; Kim, Ki-Rim; Park, Kwang-Kyun

2014-09-01

Allium victorialis var. platyphyllum is an edible perennial herb and has been used as a vegetable or as a Korean traditional medicine. Allium species have received much attention owing to their diverse pharmacological properties, including antioxidative, anti-inflammatory, and anticancer activities. However, A. victorialis var. platyphyllum needs more study. The chemopreventive potential of A. victorialis var. platyphyllum methanol extracts was examined by measuring 12-O-tetra-decanoylphorbol 13-acetate (TPA)-induced superoxide anion production in the differentiated HL-60 cells, TPA-induced mouse ear edema, and Ames/Salmonella mutagenicity. The apoptosis-inducing capabilities of the extracts were evaluated by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay, 4',6-diamidino-2-phenylindole staining, and the DNA fragmentation assay in human colon cancer HT-29 cells. Antimetastatic activities of the extracts were also investigated in an experimental mouse lung metastasis model. The methanol extracts of A. victorialis var. platyphyllum rhizome (AVP-R) and A. victorialis var. platyphyllum stem (AVP-S) dose-dependently inhibited the TPA-induced generation of superoxide anion in HL-60 cells and TPA-induced ear edema in mice, as well as 7,12-dimethylbenz[a]anthracene (DMBA) and tert-butyl hydroperoxide (t-BOOH) -induced bacterial mutagenesis. AVP-R and AVP-S reduced cell viability in a dose-related manner and induced apoptotic morphological changes and internucleosomal DNA fragmentation in HT-29 cells. In the experimental mouse lung metastasis model, the formation of tumor nodules in lung tissue was significantly inhibited by the treatment of the extracts. AVP-R and AVP-S possess antioxidative, anti-inflammatory, antimutagenic, proapoptotic, and antimetastatic activities. Therefore, these extracts can serve as a beneficial supplement for the prevention and treatment of cancer.

Managing cancer risk and decision making after kidney transplantation.

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Webster, A C; Wong, G; Craig, J C; Chapman, J R

2008-11-01

Kidney transplant recipients are at higher risk of cancer at most sites, and cancer after transplantation causes considerable morbidity and mortality. To optimize long-term patient outcomes, clinicians balance the prospect of graft failure and dialysis, with competing risks of diabetes, cardiovascular and cerebrovascular disease and the risk of malignancy. In this paper we critically examine the assumptions underpinning primary prevention, immunization, chemoprevention and screening programs, and highlight considerations when applying evidence to the kidney transplant population, and suggest a clinical research agenda that aims to define a rational approach to managing posttransplant cancer risk.

Chemoprevention of esophageal adenocarcinoma in a rat model by ursodeoxycholic acid.

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Ojima, Eisuke; Fujimura, Takashi; Oyama, Katsunobu; Tsukada, Tomoya; Kinoshita, Jun; Miyashita, Tomoharu; Tajima, Hidehiro; Fushida, Sachio; Harada, Shin-ichi; Mukaisho, Ken-ichi; Hattori, Takanori; Ohta, Tetsuo

2015-08-01

Reflux of bile acid into the esophagus induces esophagitis, inflammation-stimulated hyperplasia, metaplasia such as Barrett's esophagus (BE), and esophageal adenocarcinoma (EAC). Caudal-type homeobox 2 (Cdx2) via nuclear factor (NF)-κB induced by bile acid is an important factor in the development of BE and EAC. In colorectal cancer, experimental data suggest a chemopreventive effect of ursodeoxycholic acid (UDCA). We hypothesized that UDCA may protect against the esophageal inflammation-metaplasia-carcinoma sequence by decreasing the overall proportion of the toxic bile acids. Wistar male rats that underwent a duodenoesophageal reflux procedure were divided into two groups. One group was given commercial chow (control group), and the other was given experimental chow containing UDCA (UDCA group). The animals were killed at 40 weeks after surgery, and their bile and esophagus were examined. In the UDCA group, the esophagitis was milder and the incidence of BE was significantly lower (p acid, UDCA was markedly increased in the UDCA group compared with the control group (32.7 ± 11.4 vs. 0.82 ± 0.33 mmol/L, p acid was decreased (32.7 ± 4.05 vs. 60.9 ± 8.26 mmol/L, p acid composition.

Antitumor properties and modulation of antioxidant enzymes' activity by Aloe vera leaf active principles isolated via supercritical carbon dioxide extraction.

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El-Shemy, H A; Aboul-Soud, M A M; Nassr-Allah, A A; Aboul-Enein, K M; Kabash, A; Yagi, A

2010-01-01

The aim of this study was to evaluate the potential anticancer properties and modulatory effect of selected Aloe vera (A. vera) active principles on antioxidant enzyme activities. Thus, three anthraquinones (Namely: aloesin, aloe-emodin and barbaloin) were extracted from A. vera leaves by supercritical fluid extraction and subsequently purified by high performance liquid chromatography. Additionally, the N-terminal octapeptide derived from verectin, a biologically active 14 kDa glycoprotein present in A. vera, was also tested. In vivo, active principles exhibited significant prolongation of the life span of tumor-transplanted animals in the following order: barbaloin> octapeptide> aloesin > aloe-emodin. A. vera active principles exhibited significant inhibition on Ehrlich ascite carcinoma cell (EACC) number, when compared to positive control group, in the following order: barbaloin> aloe-emodin > octapeptide > aloesin. Moreover, in trypan blue cell viability assay, active principles showed a significant concentration-dependent cytotoxicity against acute myeloid leukemia (AML) and acute lymphocytes leukemia (ALL) cancerous cells. Furthermore, in MTT cell viability test, aloe-emodin was found to be active against two human colon cancer cell lines (i.e. DLD-1 and HT2), with IC(50) values of 8.94 and 10.78 microM, respectively. Treatments of human AML leukemic cells with active principles (100 microg ml(-1)) resulted in varying intensities of internucleosomal DNA fragmentation, hallmark of cells undergoing apoptosis, in the following order: aloe-emodin> aloesin> barbaloin> octapeptide. Intererstingly, treatment of EACC tumors with active principles resulted in a significant elevation activity of key antioxidant enzymes (SOD, GST, tGPx, and LDH). Our data suggest that the tested A. vera compounds may exert their chemo-preventive effect through modulating antioxidant and detoxification enzyme activity levels, as they are one of the indicators of tumorigenesis. These

Cancer preventive and curative attributes of plants of the Cactaceae family: a review.

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Harlev, Eli; Nevo, Eviatar; Solowey, Elaine; Bishayee, Anupam

2013-06-01

The ever-increasing occurrence of cancer and the severe side effects and limited efficacy of current cancer chemotherapy based on chemical drugs shift the attention toward drugs of plant origin. The Cactaceae family comprises more than 1500 species, but until recently only a few of them have been tested for their chemopreventive and anticancer attributes, leaving a wide unexplored area still waiting for researchers to investigate. Considering this fact, and also the promising results obtained with the relatively few plants of this family already tested, it should justly be expected that some plants of the Cactaceae family yet unexplored might possess outstanding anticancer attributes, exceeding those displayed by the plants already tested. This review presents in vitro and in vivo experimental evidence on cancer chemopreventive and therapeutic potential of bioactive phytoconstituents and extracts derived from cactus plants. It also examines the underlying biochemical and molecular mechanisms involved in the antineoplastic effects of plants of the Cactaceae family. Current limitation and future directions of research towards effective use of cacti to develop efficient and side effect-free future cancer-preventive and anticancer drugs are also discussed. Georg Thieme Verlag KG Stuttgart · New York.

Sulforaphane – a possible agent in prevention and therapy of cancer

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Joanna Tomczyk

2010-11-01

Full Text Available Sulforaphane (SFN is an isothiocyanate that is naturally present in cruciferous vegetables, with high concentration in broccoli. The results of the most recent studies indicate multi-targeted sulforaphane actions which may contribute to prevention and therapy of cancer. Protective properties of sulforaphane have been observed in every stage of carcinogenesis. The mechanism of protection against the initiation of carcinogenesis by SFN includes modulation of phase I and II xenobiotic-metabolizing enzymes, as well as direct blocking of specific binding sites of carcinogens with the DNA molecule. As a result, sulforaphane inhibits DNA adduct formation, thus reducing the risk of mutations. Further sulforaphane activity is targeted at cancer cells and prevents their expansion due to regulation of proliferation and induction of differentiation or apoptosis. In vitro studies using various types of cancer cells have revealed the ability of SFN to arrest the cell cycle, particularly in G2/M, while SFN at higher concentration is shown to activate apoptotic pathways. The possible SFN anticancer effect in the progression stage of carcinogenesis has been proved by only a few studies, which provide evidence for its antiangiogenic and antimetastatic influence. Additionally, SFN exhibits anti-inflammatory and antibacterial effects relevant to cancer prevention.Apart from the biological activity of SFN, this review also focuses on its bioavailability and tissue distribution as well as individuals’ genetic predispositions as significant factors influencing the potential efficiency of chemoprevention using this compound.

Tamoxifen for women at high risk of breast cancer

OpenAIRE

Nazarali, Safia A; Narod, Steven A

2014-01-01

Safia A Nazarali, Steven A Narod Women's College Research Institute, Women's College Hospital, and The University of Toronto, Toronto, Ontario, Canada Abstract: Tamoxifen has been used as a treatment for women who have been diagnosed with breast cancer for roughly four decades and has been approved as chemoprevention for over ten years. Although tamoxifen has been proven to be beneficial in preventing breast cancer in high-risk women, its use has not been widely embraced. To ...

Development of Targeted, Enzyme-Activated Nano-Conjugates for Hepatic Cancer Therapy

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Kuruvilla, Sibu Philip

Hepatocellular carcinoma (HCC) is the 5th most commonly-occurring cancer worldwide and the 2nd highest cause for cancer-related deaths globally. The current treatment strategy is the direct injection of a chemotherapeutic agent (e.g. doxorubicin; DOX) into the hepatic artery, through a process called hepatic arterial infusion (HAI). Unfortunately, HAI is severely hindered by limited therapeutic efficacy against the tumor and high systemic toxicity to surrounding organs (e.g. cardiotoxicity). This thesis focuses on the development of a targeted, nanoparticle-based drug delivery system aimed to improve the clinical treatment of HCC. In particular, we employ generation 5 (G5) poly(amido amine) (PAMAM) dendrimers targeted to hepatic cancer cells via N-acetylgalactosamine (NAcGal) ligands attached to the surface through a poly(ethylene glycol) (PEG) brush. DOX is attached to the G5 surface through two different enzyme-sensitive linkages, L3 or L4, to achieve controllable release of the drug inside hepatic cancer cells. The combination of NAcGal-PEG targeting branches with either L3- or L4-DOX linkages led to the development of P1 and P2 particles, respectively. In Part 1, we discuss the development of these particles and measure their ability to target and kill hepatic cancer cells in vitro. In Part 2, we investigate the antitumor activity of P1 and P2 particles in tumor-bearing mice in comparison to the free drug, and we measure the cardiac function of mice undergoing treatment to assess differences in DOX-induced cardiotoxicity. Finally, in Part 3, we explore multi-valent targeting of G5 dendrimers in pursuit of further improving their specificity to hepatic cancer cells. Ultimately, this thesis provides insight into the utility of nanoparticle-based drug delivery systems that can potentially be translated to the clinic to improve cancer therapy.

SPIN1, negatively regulated by miR-148/152, enhances Adriamycin resistance via upregulating drug metabolizing enzymes and transporter in breast cancer.

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Chen, Xu; Wang, Ya-Wen; Gao, Peng

2018-05-09

Spindlin1 (SPIN1), a protein highly expressed in several human cancers, has been correlated with tumorigenesis and development. Alterations of drug metabolizing enzymes and drug transporters are major determinants of chemoresistance in tumor cells. However, whether the metabolizing enzymes and transporters are under the control of SPIN1 in breast cancer chemoresistance has not yet been defined. SPIN1 expression in breast cancer cells and tissues was detected by quantitative real-time PCR (qRT-PCR) and immunohistochemistry. Chemosensitivity assays in vitro and in vivo were performed to determine the effect of SPIN1 on Adriamycin resistance. Downstream effectors of SPIN1 were screened by microarray and confirmed by qRT-PCR and Western blot. Luciferase assay and Western blot were used to identify miRNAs regulating SPIN1. We showed that SPIN1 was significantly elevated in drug-resistant breast cancer cell lines and tissues, compared with the chemosensitive ones. SPIN1 enhanced Adriamycin resistance of breast cancer cells in vitro, and downregulation of SPIN1 by miRNA could decrease Adriamycin resistance in vivo. Mechanistically, drug metabolizing enzymes and transporter CYP2C8, UGT2B4, UGT2B17 and ABCB4 were proven to be downstream effectors of SPIN1. Notably, SPIN1 was identified as a direct target of the miR-148/152 family (miR-148a-3p, miR-148b-3p and miR-152-3p). As expected, miR-148a-3p, miR-148b-3p or miR-152-3p could increase Adriamycin sensitivity in breast cancer cells in vitro. Moreover, high expression of SPIN1 or low expression of the miR-148/152 family predicted poorer survival in breast cancer patients. Our results establish that SPIN1, negatively regulated by the miR-148/152 family, enhances Adriamycin resistance in breast cancer via upregulating the expression of drug metabolizing enzymes and drug transporter.

Primary prevention of colorectal cancer: myth or reality?

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Crosara Teixeira, Marcela; Braghiroli, Maria Ignez; Sabbaga, Jorge; Hoff, Paulo M

2014-11-07

Colorectal cancer incidence has been rising strongly in parallel with economic development. In the past few decades, much has been learned about the lifestyle, dietary and medication risk factors for this malignancy. With respect to lifestyle, compelling evidence indicates that prevention of weight gain and maintenance of a reasonable level of physical activity can positively influence in lowering the risk. Although there is controversy about the role of specific nutritional factors, consideration of dietary pattern as a whole appears useful for formulating recommendations. Though quite often recommended, the role for many supplements, including omega-3, vitamin D, folate, and vitamin B6, remains unsettled. Only calcium and vitamin D supplementation appear to add a modest benefit, particularly in those with a low daily intake. With regard to chemoprevention, medications such as aspirin and nonsteroidal anti-inflammatory drugs, and postmenopausal hormonal replacement for women might be associated with substantial reductions in colorectal cancer risk, though their utility is affected by their side effect profile. However, the role of agents such as statins, bisphosphonates and antioxidants have yet to be determined. Ultimately, primary prevention strategies focusing on modifying environmental, lifestyle risk factors, and chemopreventive drugs are options that have already been tested, and may impact on colon cancer incidence.

Screening of Missense SNPs in Coding Regions of COX-2 as a Key Enzyme Involved in Cancer

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Sodabeh Jahanbakhsh-Godehkahriz

2013-09-01

Full Text Available Background & Objectives: Non-synonymous single nucleotide polymorphism (nsSNPs which results in disruption of protein function are used as markers in linkage and association of human proteins that might be involved in diseases and cancers .   Methods: To study the functional effect of nsSNP in cyclooxygenase-2 (COX2 amino acids, the nucleotide sequences encoding COX-2 gene in cancers were extracted from the NCBI (gi|223941909 data bank (283 cases and analyzed by SIFT, I-Mutant 2.0, SNP and GO, PANTHER and FASTSNP servers. These servers involve programs that predict the effects of amino acid substitution on protein function, stability and missense .   Results: COX-2 is an essential enzyme for the production of pro-inflammatory prostaglandins which are relevant to cancer development and progression. The substitutions in some positions such as R228H and S428A of COX-2 in most of cancers linked to reformed protein function through disruption in enzyme active site.   Conclusion: Amino acid substitutions as a consequence of COX-2 nsSNPs have important role in human disease. Substitutions which are located in catalytic domain are important for the enzymatic function of COX-2 and associated with higher expression of COX-2.

Chemoprevention of skin cancer with 1,1-Bis (3'-indolyl-1-(aromatic methane analog through induction of the orphan nuclear receptor, NR4A2 (Nurr1.

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Cedar H A Boakye

Full Text Available The objective of this study was to demonstrate the anti-skin cancer and chemopreventive potential of 1,1-bis(3'-indolyl-1-(p-chlorophenyl methane (DIM-D using an in vitro model.In vitro cell cytotoxicity and viability assays were carried out in A431 human epidermoid carcinoma cell line and normal human epidermal keratinocytes (NHEK respectively by crystal violet staining. Apoptosis induction in A431 cells (DIM-D treated and NHEK cells pretreated with DIM-D (2 hr prior to UVB irradiation, were assessed. The accumulation of reactive oxygen species (ROS in DIM-D pretreated NHEK cells (2 hr prior to UVB exposure was also determined. Immunocytochemistry and western blot analysis was performed to determine cleaved caspase 3 and DNA damage markers in DIM-D treated A431 cells and in DIM-D pretreated NHEK cells prior to UVB irradiation.The IC50 values of DIM-D were 68.7 ± 7.3, 48.3 ± 10.1 and 11.5 ± 3.1 μM whilst for Epigallocatechin gallate (EGCG were 419.1 ± 8.3, 186.1 ± 5.2 and 56.7 ± 3.1 μM for 24, 48 and 72 hr treatments respectively. DIM-D exhibited a significantly (p<0.05 greater induction of DNA fragmentation in A431 cells compared to EGCG with percent cell death of 38.9. In addition, DIM-D induced higher expression in A431 cells compared to EGCG of cleaved caspase 3 (3.0-fold vs. 2.4-fold changes, Nurr1 (2.7-fold vs. 1.7-fold changes and NFκB (1.3-fold vs. 1.1-fold changes. DIM-D also exhibited chemopreventive activity in UVB-irradiated NHEK cells by significantly (p<0.05 reducing UVB-induced ROS formation and apoptosis compared to EGCG. Additionally, DIM-D induced expression of Nurr1 but reduced expression of 8-OHdG significantly in UVB-irradiated NHEK cells compared to EGCG and UV only.Our results suggest that DIM-D exhibits Nurr1-dependent transactivation in the induction of apoptosis in A431 cells and it protects NHEK cells against UVB-induced ROS formation and DNA damage.

Nutrition Frontiers - Summer 2016 | Division of Cancer Prevention

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Volume 7, Issue 3 The summer issue of Nutrition Frontiers showcases the combined effects of ursolic acid and resveratrol for skin cancer, the potential chemopreventive effects of the dietary supplement 4-MU, and a method to monitor a heterocyclic aromatic amine in dyed hair. Learn about our spotlight investigators, Drs. Michael Caligiuri and Jianhua Yu, and their research on

Nutrition Frontiers - Spring 2016 | Division of Cancer Prevention

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Volume 7, Issue 2 The spring issue of Nutrition Frontiers showcases green tea's effect on human metabolism, fish oil — as a chemopreventive agent in myeloid leukemia and, with pectin, how they affect microRNA expression in the colon. Learn about our spotlight investigator, Dr. Richard Eckert, and his research on skin cancer prevention, upcoming announcements and more. |

Cancer chemopreventive potential of apples, apple juice, and apple components.

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Gerhauser, Clarissa

2008-10-01

Apples ( MALUS sp., Rosaceae) are a rich source of nutrient as well as non-nutrient components and contain high levels of polyphenols and other phytochemicals. Main structural classes of apple constituents include hydroxycinnamic acids, dihydrochalcones, flavonols (quercetin glycosides), catechins and oligomeric procyanidins, as well as triterpenoids in apple peel and anthocyanins in red apples. Several lines of evidence suggest that apples and apple products possess a wide range of biological activities which may contribute to health beneficial effects against cardiovascular disease, asthma and pulmonary dysfunction, diabetes, obesity, and cancer (reviewed by Boyer and Liu, Nutr J 2004). The present review will summarize the current knowledge on potential cancer preventive effects of apples, apple juice and apple extracts (jointly designated as apple products). In brief, apple extracts and components, especially oligomeric procyanidins, have been shown to influence multiple mechanisms relevant for cancer prevention in IN VITRO studies. These include antimutagenic activity, modulation of carcinogen metabolism, antioxidant activity, anti-inflammatory mechanisms, modulation of signal transduction pathways, antiproliferative and apoptosis-inducing activity, as well as novel mechanisms on epigenetic events and innate immunity. Apple products have been shown to prevent skin, mammary and colon carcinogenesis in animal models. Epidemiological observations indicate that regular consumption of one or more apples a day may reduce the risk for lung and colon cancer.

The effectiveness of cyclooxygenase-2 inhibitors and evaluation of angiogenesis in the model of experimental colorectal cancer.

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Gungor, Hilal; Ilhan, Nevin; Eroksuz, Hatice

2018-06-01

Colorectal cancer (CRC) is an important cause of cancer-related deaths worldwide. Early diagnosis and treatment of CRCs are of importance for improving the survival. In the present study, we studied the effects of nonsteroidal anti-inflammatory drugs (NSAIDs)-induced chemopreventive effects on tumor development incidence and angiogenesis in experimental CRC rats. 1,2-Dimethylhydrazine dihydrochloride (DMH) was used as cancer-inducing agent and two NSAIDs (celecoxib and diclofenac) were given orally as chemopreventive agents. Histopathological and immuno histochemical evaluations were performed in colorectal tissue samples, whereas angiogenesis parameters were studied in blood samples. Histopathological examination showed that adenocarcinoma (62.5%), dysplastic changes (31.25%) and inflammattory changes (6.25%) were detected in DMH group, whereas no pathological change was observed in control rats. In treatment groups, there was marked decrease in adenocarcinoma rate (30% and 10%, respectively). A significant increase was detected in MMP-2, MMP-9 levels and MMP-2/TIMP-2 ratio in DMH group as compared with controls and treatment groups. In immunohistochemical evaluations, there was an increase in intensity and extent of staining of MMP-2 and MMP-9 in DMH group as compared to controls and treatment groups. The decrease in celecoxib group was more prominent. Overall, it was concluded that NSAIDs, particularly cyclooxygenase-2 (COX-2) inhibitors, might have a protective effect on CRC development and slow down progression of tumor in a DMH-induced experimental cancer model. One of the possible mechanisms in the chemoprevention of colon cancer seems to be inhibition of angiogenesis by diclofenac and celecoxib. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Chemopreventive properties of raisins originating from Greece in colon cancer cells.

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Kountouri, Aggeliki M; Gioxari, Aristea; Karvela, Evangelia; Kaliora, Andriana C; Karvelas, Michalis; Karathanos, Vaios T

2013-02-26

Colorectal cancer is one of the major causes of cancer-related mortality in humans in both developed and developing countries. Dietary patterns influence the risk of colon cancer development, while plant-derived foods have gained great interest, due to the high content of antioxidants. Corinthian raisins (Currants, CR) and Sultanas (S) (Vitis vinifera L., Vitaceae) are dried vine fruits produced in Greece with many culinary uses in both the Mediterranean and the Western nutrition. In the present study, we investigated the effects of CR and S on human colon cancer cells. Methanol extracts of CR and S were used at different concentrations. The total polyphenol content and anti-radical activity were measured by Folin-Ciocalteu and DPPH, respectively. Antioxidant, anti-inflammatory and anti-proliferative effects on HT29 cell culture were evaluated. All extracts exhibited DPPH˙ scavenging activity in a dose-dependent manner. Both products suppressed cell proliferation, while the levels of glutathione and cyclooxygenase 2 were significantly decreased. A significant reduction in IL-8 levels and NF-kappaB p65 activation was also observed. Both antioxidant and anti-inflammatory effects were dependent on the duration of exposure. Results indicate that the methanol extracts of CR and S exhibit anti-radical activity in vitro, as well as cancer preventive efficacy on colon cancer cells, with S having slightly higher activity. The beneficial properties of these unique dried grapes are attributed to their high content of phenolic compounds.

Virtual Dual inhibition of COX-2 / 5-LOX enzymes based on binding properties of alpha-amyrins, the anti-inflammatory compound as a promising anti-cancer drug

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Ranjbar, Mohammad Mehdi; Assadolahi, Vahideh; Yazdani, Mohsen; Nikaein, Donya; Rashidieh, Behnam

2016-01-01

Hydro-alcoholic fruit extract of Cordia myxa was considerably effective on curing acute inflammation in mouse model. Previous studies suggested significant anti-inflammatory activities as well as potential anticancer agent of α-amyrins in seeds. Inhibition of Cyclooxygenase-2 (COX-2) and 5-Lipooxygenase (5-LOX) is significant in cancer prevention and therapeutics although this inhibition with chemo-drugs has its own side-effects. It is shown that these enzymes pathways are related to several cancers including colon, breast and lung cancer. This study was conducted based on Cordia species' α-amyrins as a safer natural anti-cancer compound for inhibition of COX-2 and 5-LOX enzymes by molecular docking. The X-ray crystal structure of COX2 / 5-LOX enzymes and α-amyrins was retrieved and energetically minimized respectively. The binding site and surface of enzymes were detected. Docking studies were performed by AutoDock 4.2 using Lamarckian genetic algorithm (LGA). Finally drug likeness, molecular pharmacokinetic properties and toxicity of α-amyrins was calculated. Molecular Docking revealed hydrogen and hydrophobic interactions between α-amyrins with both active sites of COX-2 and 5-LOX enzymes. Interestingly, it covalently bonded to Fe cofactor of 5-LOX enzyme and chelated this molecule. Base on binding energies (∆G) α-amyrin has more inhibitory effects on 5-LOX (-10.45 Kcal/mol) than COX-2 (-8.02 Kcal/mol). Analysis of molecular pharmacokinetic parameters suggested that α-amyrins complied with most sets of Lipinski's rules, and so it could be a suitable ligand for docking studies. Eventually, bioactivity score showed α-amyrins possess considerable biological activities as nuclear receptor, enzyme inhibitor, GPCR and protease inhibitor ligand. These results clearly demonstrate that α-amyrins could act as potential highly selective COX-/5-LOX inhibitor. Also, it is a safe compound in comparison with classical non-steroidal anti-inflammatory drugs (NSAIDs

The Chemopreventive Effect of Tanacetum Polycephalum Against LA7-Induced Breast Cancer in Rats and the Apoptotic Effect of a Cytotoxic Sesquiterpene Lactone in MCF7 Cells: A Bioassay-Guided Approach

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Hamed Karimian

2015-06-01

Full Text Available Background: Tanacetum polycephalum L. Schultz-Bip is a member of the Asteraceae family. This study evaluated the chemopreventive effect of a T. polycephalum hexane extract (TPHE using in in vivo and in vitro models. Methods and Results: Five groups of rats: normal control, cancer control, TPHE low dose, TPHE high dose and positive control (tamoxifen were used for the in vivo study. Histopathological examination showed that TPHE significantly suppressed the carcinogenic effect of LA7 tumour cells. The tumour sections from TPHE-treated rats demonstrated significantly reduced expression of Ki67 and PCNA compared to the cancer control group. Using a bioassay-guided approach, the cytotoxic compound of TPHE was identified as a tricyclic sesquiterpene lactone, namely, 8β- hydroxyl- 4β, 15- dihydrozaluzanin C (HDZC. Signs of early and late apoptosis were observed in MCF7 cells treated with HDZC and were attributed to the mitochondrial intrinsic pathway based on the up-regulation of Bax and the down-regulation of Bcl-2. HDZC induced cell cycle arrest in MCF7 cells and increased the expression of p21 and p27 at the mRNA and protein levels. Conclusion: This results of this study substantiate the anticancer effect of TPHE and highlight the involvement of HDZC as one of the contributing compounds that act by initiating mitochondrial-mediated apoptosis.

Transforming Cancer Prevention through Precision Medicine and Immune-oncology.

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Kensler, Thomas W; Spira, Avrum; Garber, Judy E; Szabo, Eva; Lee, J Jack; Dong, Zigang; Dannenberg, Andrew J; Hait, William N; Blackburn, Elizabeth; Davidson, Nancy E; Foti, Margaret; Lippman, Scott M

2016-01-01

We have entered a transformative period in cancer prevention (including early detection). Remarkable progress in precision medicine and immune-oncology, driven by extraordinary recent advances in genome-wide sequencing, big-data analytics, blood-based technologies, and deep understanding of the tumor immune microenvironment (TME), has provided unprecedented possibilities to study the biology of premalignancy. The pace of research and discovery in precision medicine and immunoprevention has been astonishing and includes the following clinical firsts reported in 2015: driver mutations detected in circulating cell-free DNA in patients with premalignant lesions (lung); clonal hematopoiesis shown to be a premalignant state; molecular selection in chemoprevention randomized controlled trial (RCT; oral); striking efficacy in RCT of combination chemoprevention targeting signaling pathway alterations mechanistically linked to germline mutation (duodenum); molecular markers for early detection validated for lung cancer and showing promise for pancreatic, liver, and ovarian cancer. Identification of HPV as the essential cause of a major global cancer burden, including HPV16 as the single driver of an epidemic of oropharyngeal cancer in men, provides unique opportunities for the dissemination and implementation of public health interventions. Important to immunoprevention beyond viral vaccines, genetic drivers of premalignant progression were associated with increasing immunosuppressive TME; and Kras vaccine efficacy in pancreas genetically engineered mouse (GEM) model required an inhibitory adjuvant (Treg depletion). In addition to developing new (e.g., epigenetic) TME regulators, recent mechanistic studies of repurposed drugs (aspirin, metformin, and tamoxifen) have identified potent immune activity. Just as precision medicine and immune-oncology are revolutionizing cancer therapy, these approaches are transforming cancer prevention. Here, we set out a brief agenda for the

Renin-angiotensin system inhibitors, angiotensin I-converting enzyme gene insertion/deletion polymorphism, and cancer: The Rotterdam study

NARCIS (Netherlands)

R. van der Knaap (Ronald); C. Siemes (Claire); J.W.W. Coebergh (Jan Willem); P. Tikka-Kleemola (Päivi); A. Hofman (Albert); B.H.Ch. Stricker (Bruno)

2008-01-01

textabstractBACKGROUND. Angiotensin I-converting enzyme (ACE) inhibitors, angiotensin II antagonists, and the ACE insertion/deletion (I/D) gene polymorphism all influence serum angiotensin II action. Because angiotensin II levels have been associated with cancer, the objective of the current

Carcinogenicity of chromium and chemoprevention: a brief update

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Wang Y

2017-08-01

Full Text Available Yafei Wang,1,* Hong Su,1,* Yuanliang Gu,1 Xin Song,1 Jinshun Zhao1,2 1Department of Preventative Medicine, Zhejiang Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo, People’s Republic of China; 2Toxicology and Molecular Biology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, USA *These authors contributed equally to this work Abstract: Chromium has two main valence states: hexavalent chromium (Cr[VI] and trivalent chromium (Cr[III]. Cr(VI, a well-established human carcinogen, can enter cells by way of a sulfate/phosphate anion-transport system, and then be reduced to lower-valence intermediates consisting of pentavalent chromium (Cr[V], tetravalent chromium (Cr[IV] or Cr(III via cellular reductants. These intermediates may directly or indirectly result in DNA damage or DNA–protein cross-links. Although Cr(III complexes cannot pass easily through cell membranes, they have the ability to accumulate around cells to induce cell-surface morphological alteration and result in cell-membrane lipid injuries via disruption of cellular functions and integrity, and finally to cause DNA damage. In recent years, more research, including in vitro, in vivo, and epidemiological studies, has been conducted to evaluate the genotoxicity/carcinogenicity induced by Cr(VI and/or Cr(III compounds. At the same time, various therapeutic agents, especially antioxidants, have been explored through in vitro and in vivo studies for preventing chromium-induced genotoxicity/carcinogenesis. This review aims to provide a brief update on the carcinogenicity of Cr(VI and Cr(III and chemoprevention with different antioxidants. Keywords: hexavalent chromium, Cr(VI, trivalent chromium, Cr(III, genotoxicity, carcinogenicity, chemoprevention, antioxidant 

Effect of Chemical Prevention Drugs-based MicroRNAs and Their Target Genes 
on Tumor Inhibition

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Yanhui JIANG

2015-04-01

Full Text Available Chemopreventive drugs including natural chemopreventive drugs and synthetic chemopreventive drugs, it not only can prevent cancer, can also play a role in tumor treatment. MicroRNAs (miRNAs is a kind of short chains of non-coding RNA, regulating the expression of many genes through the way of degradation of mRNA or inhibitting mRNA translation. In recent years, more and more studies have shown that chemopreventive drugs through influence the expression of miRNAs and their target genes play a role in the prevention and treatment in a variety of tumors, and chemopreventive drugs on the experimental study of miRNAs and their target genes in tumor have demonstrated a good safety and efficacy. Effect on chemopreventive drugs-based microRNAs and their target genes into cancer cells will be expected as a new starting point for cancer research. The thesis expounds and analyzes between the natural chemopreventive drugs and synthetic chemopreventive drugs and miRNAs and their target genes in tumor research progress.

­­The Effects of Naringenin on Some Human Breast Cancer Cells: A Systematic Review

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Zahra Akbarzadeh

2016-06-01

Full Text Available Background: Breast cancer is the most common cancer in women worldwide. Recently, natural remedies such as Naringenin (Nar - a kind of flavonoids which can be found in grapefruits, oranges, and tomatoes - seem to be interesting. They play a useful role in treatment and chemoprevention because of having pleiotropic molecular mechanisms of action on breast cancer cells.Methods: We performed a PRISMA-directed systematic review to investigate the effects of Naringenin on some human breast cancer cells (MCF-7, T47D, and MDA-MB-231. Tumor size, apoptosis, estrogenic properties, and cytotoxicity were assessed as primary outcomes. The systematic search without restriction was conducted in electronic databases, including PubMed, Scopus, Google scholar, and Cochrane Library.Results: Initially, 6445 articles were identified. After screening their titles and abstracts, 32 studies were selected for text appraisal. Finally, 6 articles which met the inclusion criteria were evaluated. Based on the evaluation, Nar could inhibit both cell proliferation and tumor growth at different concentration. Moreover, it could induce apoptosis.Conclusions: Due to anticancer properties of Nar, some probable mechanisms of these effects are induction of alteration in aromatase and caspase enzymes, and suppression of oestrogen signal transduction pathways. However, more investigations are necessary in the future to decide whether Nar consumption is recommendable as part of breast cancer treatment and control. Also, some clinical trials should be designed to determine the optimal dose for the therapeutic use.

Androgen Receptor Signaling in Bladder Cancer

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Li, Peng; Chen, Jinbo; Miyamoto, Hiroshi

2017-01-01

Emerging preclinical findings have indicated that steroid hormone receptor signaling plays an important role in bladder cancer outgrowth. In particular, androgen-mediated androgen receptor signals have been shown to correlate with the promotion of tumor development and progression, which may clearly explain some sex-specific differences in bladder cancer. This review summarizes and discusses the available data, suggesting the involvement of androgens and/or the androgen receptor pathways in urothelial carcinogenesis as well as tumor growth. While the precise mechanisms of the functions of the androgen receptor in urothelial cells remain far from being fully understood, current evidence may offer chemopreventive or therapeutic options, using androgen deprivation therapy, in patients with bladder cancer. PMID:28241422

Androgen Receptor Signaling in Bladder Cancer

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Peng Li

2017-02-01

Full Text Available Emerging preclinical findings have indicated that steroid hormone receptor signaling plays an important role in bladder cancer outgrowth. In particular, androgen-mediated androgen receptor signals have been shown to correlate with the promotion of tumor development and progression, which may clearly explain some sex-specific differences in bladder cancer. This review summarizes and discusses the available data, suggesting the involvement of androgens and/or the androgen receptor pathways in urothelial carcinogenesis as well as tumor growth. While the precise mechanisms of the functions of the androgen receptor in urothelial cells remain far from being fully understood, current evidence may offer chemopreventive or therapeutic options, using androgen deprivation therapy, in patients with bladder cancer.

The protective role of carotenoids and polyphenols in patients with head and neck cancer

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Hui-Ping Chang

2015-02-01

Full Text Available Head and neck cancer is a critical global health problem and approximately 650,000 patients per year are diagnosed with this type of cancer. In addition, head and neck cancer exhibits a high recurrence rate, readily causing second primary cancers in other locations, often yielding a poor prognosis. Current medical and surgical treatment options result in considerable impairment of speaking and swallowing functions, with side effects such as nausea, vomiting, bone marrow suppression, and renal damage, thereby impairing patients' quality of life. Thus, developing a prevention and therapeutic intervention strategy for head and neck cancer is vital. Phytochemicals have been shown to have a unique ability to protect cells from damage and modulation of cell repair. The chemopreventive activities of phytochemicals have also been demonstrated to be associated with their antioxidant properties and the induction and stimulation of intercellular communication via gap junctions, which play a role in the regulation of cancer cell cycle, differentiation, apoptosis, and stagnate cancer cell growth. Phytochemicals can also regulate cancer cell signaling pathways, reduce the invasion and metastasis of cancer cells, and protect normal cells during treatment, thus reducing the damage caused by chemotherapy and radiotherapy. The most studied of the chemopreventive effects of phytochemicals are the carotenoids and phenolics. In this review, we investigated the multiple mechanisms of carotenoids and polyphenols (PPs for use in preventing head and neck cancer, reducing the side effects of chemotherapy and radiotherapy, improving patient survival rates, and reducing the occurrence rate of second primary cancers.

Chemopreventive agents attenuate rapid inhibition of gap junctional intercellular communication induced by environmental toxicants

Czech Academy of Sciences Publication Activity Database

Babica, Pavel; Čtveráčková, Lucie; Lenčešová, Zuzana; Trosko, J. E.; Upham, B. L.

2016-01-01

Roč. 68, č. 5 (2016), s. 827-837 ISSN 0163-5581 R&D Projects: GA MŠk LH12034 Institutional support: RVO:67985939 Keywords : gap junctional intercellular communication * chemopreventive agents * environmental toxicants Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 2.447, year: 2016

Oral cancer cells may rewire alternative metabolic pathways to survive from siRNA silencing of metabolic enzymes

International Nuclear Information System (INIS)

Zhang, Min; Chai, Yang D; Brumbaugh, Jeffrey; Liu, Xiaojun; Rabii, Ramin; Feng, Sizhe; Misuno, Kaori; Messadi, Diana; Hu, Shen

2014-01-01

Cancer cells may undergo metabolic adaptations that support their growth as well as drug resistance properties. The purpose of this study is to test if oral cancer cells can overcome the metabolic defects introduced by using small interfering RNA (siRNA) to knock down their expression of important metabolic enzymes. UM1 and UM2 oral cancer cells were transfected with siRNA to transketolase (TKT) or siRNA to adenylate kinase (AK2), and Western blotting was used to confirm the knockdown. Cellular uptake of glucose and glutamine and production of lactate were compared between the cancer cells with either TKT or AK2 knockdown and those transfected with control siRNA. Statistical analysis was performed with student T-test. Despite the defect in the pentose phosphate pathway caused by siRNA knockdown of TKT, the survived UM1 or UM2 cells utilized more glucose and glutamine and secreted a significantly higher amount of lactate than the cells transferred with control siRNA. We also demonstrated that siRNA knockdown of AK2 constrained the proliferation of UM1 and UM2 cells but similarly led to an increased uptake of glucose/glutamine and production of lactate by the UM1 or UM2 cells survived from siRNA silencing of AK2. Our results indicate that the metabolic defects introduced by siRNA silencing of metabolic enzymes TKT or AK2 may be compensated by alternative feedback metabolic mechanisms, suggesting that cancer cells may overcome single defective pathways through secondary metabolic network adaptations. The highly robust nature of oral cancer cell metabolism implies that a systematic medical approach targeting multiple metabolic pathways may be needed to accomplish the continued improvement of cancer treatment

Nanoencapsulation of polyphenols for protective effect against colon-rectal cancer.

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Santos, Isis S; Ponte, Bruno M; Boonme, Prapaporn; Silva, Amélia M; Souto, Eliana B

2013-01-01

The human population at large is exposed to many critical factors (e.g. bad food habits, chemical substances, and stress) leading to the development of serious diseases. Colon or colorectal cancer is one of the most prevalent types of cancer in many countries. Despite being a multi-factorial chronic disease, resulting from the interaction of multiple genetic and environmental factors, the critical factor is mostly a poor diet regimen. Therefore, an accumulation of constant mutations leads to a complex arrangement of events during tumor initiation, development and propagation. It is well known that many plants are rich in polyphenols with anti-oxidant, anti-atherogenic, anti-diabetic, anti-cancer, anti-viral, and anti-inflammatory properties. These compounds are secondary metabolites with the ability to donate electrons to free radicals through different mechanisms. In recent years, a large number of studies have attributed a protective effect to polyphenols and foods containing these compounds (e.g. plants, vegetables, cereals, tea, coffee or chocolate). Polyphenolic compounds have been described to inhibit cancer development and propagation, being used as chemopreventive agents. Some polyphenols reported a preventive action against colon cancer, e.g. curcumin, gallic acid, ellagic acid, and epigallocatechin-3-gallate. The present article focuses on the properties of these molecules as chemopreventive agents and the recent advances on their formulation in nanoparticulate systems for targeted therapy and increased bioavailability. Copyright © 2012 Elsevier Inc. All rights reserved.

The role of nutraceuticals in the regulation of Wnt and Hedgehog signaling in cancer

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Li, Yiwei; Wang, Zhiwei; Kong, Dejuan

2010-01-01

Multiple cellular signaling pathways have been involved in the processes of cancer cell invasion and metastasis. Among many signaling pathways, Wnt and Hedgehog (Hh) signaling pathways are critically involved in embryonic development, in the biology of cancer stem cells (CSCs) and in the acquisition of epithelial to mesenchymal transition (EMT), and thus this article will remain focused on Wnt and Hh signaling. Since CSCs and EMT are also known to be responsible for cancer cell invasion and metastasis, the Wnt and Hedgehog signaling pathways are also intimately associated with cancer invasion and metastasis. Emerging evidence suggests the beneficial role of chemopreventive agents commonly known as nutraceutical in cancer. Among many such agents, soy isoflavones, curcumin, green tea polyphenols, 3,3′-diindolylmethane, resveratrol, lycopene, vitamin D, etc. have been found to prevent, reverse, or delay the carcinogenic process. Interestingly, these agents have also shown to prevent or delay the progression of cancer, which could in part be due to their ability to attack CSCs or EMT-type cells by attenuating the Wnt and Hedgehog signaling pathways. In this review, we summarize the current state of our knowledge on the role of Wnt and Hedgehog signaling pathways, and their targeted inactivation by chemopreventive agents (nutraceuticals) for the prevention of tumor progression and/or treatment of human malignancies. PMID:20711635

Promoter de-methylation of cyclin D2 by sulforaphane in prostate cancer cells

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Hsu Anna

2011-10-01

Full Text Available Abstract Sulforaphane (SFN, an isothiocyanate derived from cruciferous vegetables, induces potent anti-proliferative effects in prostate cancer cells. One mechanism that may contribute to the anti-proliferative effects of SFN is the modulation of epigenetic marks, such as inhibition of histone deacetylase (HDAC enzymes. However, the effects of SFN on other common epigenetic marks such as DNA methylation are understudied. Promoter hyper-methylation of cyclin D2, a major regulator of cell cycle, is correlated with prostate cancer progression, and restoration of cyclin D2 expression exerts anti-proliferative effects on LnCap prostate cancer cells. Our study aimed to investigate the effects of SFN on DNA methylation status of cyclin D2 promoter, and how alteration in promoter methylation impacts cyclin D2 gene expression in LnCap cells. We found that SFN significantly decreased the expression of DNA methyltransferases (DNMTs, especially DNMT1 and DNMT3b. Furthermore, SFN significantly decreased methylation in cyclin D2 promoter regions containing c-Myc and multiple Sp1 binding sites. Reduced methlyation of cyclin D2 promoter corresponded to an increase in cyclin D2 transcript levels, suggesting that SFN may de-repress methylation-silenced cyclin D2 by impacting epigenetic pathways. Our results demonstrated the ability of SFN to epigenetically modulate cyclin D2 expression, and provide novel insights into the mechanisms by which SFN may regulate gene expression as a prostate cancer chemopreventive agent.

Two different approaches in skin cancer therapy: using a photosensitizer/a natural product

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Abraham, Annie; Gayathri, Devi D.; Cibin, T. R.; Ramaiah, D.

2010-02-01

This paper deals with two potential modes for the treatment of skin cancer-one a novel approach using a squaraine dye and the other using a natural product- the flavonoid fraction of Saraca asoka. Squaraine dye is a photosensitizing agent, which is preferentially taken up and retained by the tumor cells and when irradiated with high power visible light results in the selective destruction of the tumor cells by photodynamic therapy. The uniqueness of this mode of treatment lies in the selective destruction of tumor cells without affecting the neighbouring normal cells, which is much advantageous over radiation therapy now frequently used. The chemopreventive and therapeutic effects of the plant component are explored as well. The experimental models were Swiss albino mice in which skin tumor was induced by DMBA. Marked reduction in tumor volume and burden in the treated groups were observed. The reversal of biochemical enzyme markers like rhodanese, myeloperoxidase, β-D glucuronidase, lactate dehydrogenase, hexokinase and sialic acid to near normal levels were observed in the PDT and flavonoid fraction treated groups. The live photographs of the experimental animals and histopathological data further support the obtained results. The study assumes importance as it combines a traditional treatment mode and a novel aspect in cancer therapy using the same experimental models. Also this is the first report on PDT using a squaraine dye for skin cancer therapy in vivo.

Breast cancer anxiety's associations with responses to a chemoprevention decision aid.

Science.gov (United States)

Dillard, Amanda J; Scherer, Laura; Ubel, Peter A; Smith, Dylan M; Zikmund-Fisher, Brian J; McClure, Jennifer B; Greene, Sarah; Stark, Azadeh; Fagerlin, Angela

2013-01-01

Few studies have examined how specific emotions may affect decision-making processes. Anxiety may be especially relevant in health decisions such as those related to cancer in which thoughts of illness or death may be abundant. We examined associations between women's anxiety about developing breast cancer and variables related to their decision to take a medication that could reduce their chances of the disease. Six-hundred and thirty-two American women, who had an increased risk of breast cancer, reviewed a web-based decision aid about tamoxifen. We examined associations between their baseline, self-reported anxiety about developing the disease and post decision aid measures including knowledge about tamoxifen, attitude toward the medication, and behavioral intentions to look for more information and take the medication. Results showed that anxiety was not associated with knowledge about tamoxifen, but it was associated with attitude toward the medication such that women who were more anxious about developing breast cancer were more likely to think the benefits were worth the risks. Greater anxiety was also associated with greater behavioral intentions to look for additional information and take the medication in the next few months. Secondary analyses showed that behavioral intentions were related to knowledge of tamoxifen and attitude toward the medication only for women who were reporting low levels of anxiety. Overall, the findings suggest that anxiety about breast cancer may motivate interest in tamoxifen and not necessarily through affecting knowledge or attitudes. Copyright © 2012 Elsevier Ltd. All rights reserved.

Chemopreventive glucosinolate accumulation in various broccoli and collard tissues: Microfluidic-based targeted transcriptomics for by-product valorization.

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Lee, Young-Sang; Ku, Kang-Mo; Becker, Talon M; Juvik, John A

2017-01-01

Floret, leaf, and root tissues were harvested from broccoli and collard cultivars and extracted to determine their glucosinolate and hydrolysis product profiles using high performance liquid chromatography and gas chromotography. Quinone reductase inducing bioactivity, an estimate of anti-cancer chemopreventive potential, of the extracts was measured using a hepa1c1c7 murine cell line. Extracts from root tissues were significantly different from other tissues and contained high levels of gluconasturtiin and glucoerucin. Targeted gene expression analysis on glucosinolate biosynthesis revealed that broccoli root tissue has elevated gene expression of AOP2 and low expression of FMOGS-OX homologs, essentially the opposite of what was observed in broccoli florets, which accumulated high levels of glucoraphanin. Broccoli floret tissue has significantly higher nitrile formation (%) and epithionitrile specifier protein gene expression than other tissues. This study provides basic information of the glucosinolate metabolome and transcriptome for various tissues of Brassica oleracea that maybe utilized as potential byproducts for the nutraceutical market.

Oxidative stress in cancer and fibrosis: Opportunity for therapeutic intervention with antioxidant compounds, enzymes, and nanoparticles

Directory of Open Access Journals (Sweden)

Jingga Morry

2017-04-01

Full Text Available Oxidative stress, mainly contributed by reactive oxygen species (ROS, has been implicated in pathogenesis of several diseases. We review two primary examples; fibrosis and cancer. In fibrosis, ROS promote activation and proliferation of fibroblasts and myofibroblasts, activating TGF-β pathway in an autocrine manner. In cancer, ROS account for its genomic instability, resistance to apoptosis, proliferation, and angiogenesis. Importantly, ROS trigger cancer cell invasion through invadopodia formation as well as extravasation into a distant metastasis site. Use of antioxidant supplements, enzymes, and inhibitors for ROS-generating NADPH oxidases (NOX is a logical therapeutic intervention for fibrosis and cancer. We review such attempts, progress, and challenges. Lastly, we review how nanoparticles with inherent antioxidant activity can also be a promising therapeutic option, considering their additional feature as a delivery platform for drugs, genes, and imaging agents.

The role of arginine and the modified arginine deiminase enzyme ADI-PEG 20 in cancer therapy with special emphasis on Phase I/II clinical trials.

Science.gov (United States)

Synakiewicz, Anna; Stachowicz-Stencel, Teresa; Adamkiewicz-Drozynska, Elzbieta

2014-11-01

The metabolic differences between normal, healthy cells and neoplastic cells have been exploited by anticancer therapies targeting metabolic pathways. Various studies of malignant processes have demonstrated disturbances in both arginine synthesis and metabolism that enhance or inhibit tumor cell growth. Consequently, there has been an increased interest in the arginine-depleting enzyme arginine deiminase (ADI) as a potential antineoplastic therapy. This review summarizes the literature on the potential anti-cancer therapeutics arginine and ADI, an arginine-catabolizing enzyme. The authors searched the MEDLINE database PubMed using the key words: 'arginine, 'ADI', 'arginine in cancer' and 'ADI and cancer'. The authors evaluate prospective randomized studies on cancer patients between 2004 and 2013 as well as ongoing research found through the US National Institutes of Health trial database. The results of current studies are promising but do not give unequivocal answers and so it is impossible to recommend arginine or its enzyme ADI as a therapeutic. In the opinion of the authors, further identification of arginine-dependent malignant tumors and their metabolism should be investigated. Furthermore, the use of these chemicals, in combination with other chemotherapeutics drugs, should be investigated and indeed may improve the success of arginine-depleting enzymes such as pegylated ADI (ADI-PEG20).

Linking genomic responses of gonads with reproductive impairment in marine medaka (Oryzias melastigma) exposed chronically to the chemopreventive and antifouling agent, 3,3′-diindolylmethane (DIM)

Energy Technology Data Exchange (ETDEWEB)

Chen, Lianguo [Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR (China); Au, Doris W.T. [State Key Laboratory in Marine Pollution, Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR (China); Hu, Chenyan [School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430072 (China); Zhang, Weipeng [Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR (China); Zhou, Bingsheng [State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072 (China); Cai, Lin [Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR (China); Giesy, John P. [Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3 (Canada); Department of Zoology, and Center for Integrative Toxicology, Michigan State University, East Lansing, MI (United States); Qian, Pei-Yuan, E-mail: boqianpy@ust.hk [Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR (China)

2017-02-15

Highlights: • Marine medaka were exposed chronically to low-doses of DIM. • Toxicogenomic responses of gonads were profiled at transcript and protein levels. • Molecular initiating events were linked to adverse apical outcomes. • VTG mobilization was blocked by lower abundance of cathepsin enzyme in ovary. • Eggshell proteins were more indicative of reproductive failure than VTG. - Abstract: 3,3′-Diindolylmethane (DIM) has been promoted as an effective chemopreventive and antifouling additive. However, the concurrent risks or side effects of DIM are not fully understood, especially on tissues responsive to estrogen. Therefore, this study employed marine medaka (Oryzias melastigma) as a test model to evaluate relative safety and explore mechanisms of toxic action of DIM on development and function of gonad after chronic (28 days) aqueous exposure to relatively low doses (0 μg/L or 8.5 μg/L). Integration of comprehensive toxicogenomic analysis at the transcriptome and proteome levels with apical endpoints, such as production of eggs and swimming performance of larvae, elucidated the molecular linkage in gonad from bottom up along the reproductive adverse outcome pathway. A series of sequential changes at the transcript and protein levels were linked to lesser fecundity and viability of larvae exposed to DIM. Anomalous production of vitellogenin (VTG) and eggshell proteins in testis confirmed the estrogenic potency of DIM. In the ovary, although storage of VTG was greater, lesser expressions of cathepsin enzymes blocked cleavage and incorporation of VTG into oocytes as yolk, which acted together with lower eggshell proteins to inhibit maturation of primary oocyte and thus contributed to impairment of fecundity. Overall, this study demonstrated that exposure to DIM impaired reproductive fitness. Diverse molecular initiating changes in gonads were linked to apical endpoints that could be used in assessment of risks posed by DIM on gametogenesis. In

Linking genomic responses of gonads with reproductive impairment in marine medaka (Oryzias melastigma) exposed chronically to the chemopreventive and antifouling agent, 3,3′-diindolylmethane (DIM)

International Nuclear Information System (INIS)

Chen, Lianguo; Au, Doris W.T.; Hu, Chenyan; Zhang, Weipeng; Zhou, Bingsheng; Cai, Lin; Giesy, John P.; Qian, Pei-Yuan

2017-01-01

Highlights: • Marine medaka were exposed chronically to low-doses of DIM. • Toxicogenomic responses of gonads were profiled at transcript and protein levels. • Molecular initiating events were linked to adverse apical outcomes. • VTG mobilization was blocked by lower abundance of cathepsin enzyme in ovary. • Eggshell proteins were more indicative of reproductive failure than VTG. - Abstract: 3,3′-Diindolylmethane (DIM) has been promoted as an effective chemopreventive and antifouling additive. However, the concurrent risks or side effects of DIM are not fully understood, especially on tissues responsive to estrogen. Therefore, this study employed marine medaka (Oryzias melastigma) as a test model to evaluate relative safety and explore mechanisms of toxic action of DIM on development and function of gonad after chronic (28 days) aqueous exposure to relatively low doses (0 μg/L or 8.5 μg/L). Integration of comprehensive toxicogenomic analysis at the transcriptome and proteome levels with apical endpoints, such as production of eggs and swimming performance of larvae, elucidated the molecular linkage in gonad from bottom up along the reproductive adverse outcome pathway. A series of sequential changes at the transcript and protein levels were linked to lesser fecundity and viability of larvae exposed to DIM. Anomalous production of vitellogenin (VTG) and eggshell proteins in testis confirmed the estrogenic potency of DIM. In the ovary, although storage of VTG was greater, lesser expressions of cathepsin enzymes blocked cleavage and incorporation of VTG into oocytes as yolk, which acted together with lower eggshell proteins to inhibit maturation of primary oocyte and thus contributed to impairment of fecundity. Overall, this study demonstrated that exposure to DIM impaired reproductive fitness. Diverse molecular initiating changes in gonads were linked to apical endpoints that could be used in assessment of risks posed by DIM on gametogenesis. In

A Chemopreventive Trial to Study the Effects of High Tea Consumption on Smoking-Related Oxidative Stress

National Research Council Canada - National Science Library

Hakim, Iman

2004-01-01

.... We are conducting a 6-month randomized, controlled, double-blinded chemopreventive trial in a group of COPD subjects who are being randomized to green or black tea preparations or a control intervention (matching placebo...

A Chemopreventive Trial to Study the Effects of High Tea Consumption on Smoking-Related Oxidative Stress

National Research Council Canada - National Science Library

Hakim, Iman A

2006-01-01

.... We are conducting a 6-month randomized, controlled, double-blinded chemopreventive trial in a group of COPD subjects who are being randomized to green or black tea preparations or a control intervention (matching placebo...

A Chemoprevention Trial to Study the Effects of High Tea Consumption on Smoking-Related Oxidative Stress

National Research Council Canada - National Science Library

Hakim, Iman A

2005-01-01

.... We are conducting a 6-month randomized, controlled, double-blinded chemopreventive trial in a group of COPD subjects who are being randomized to green or black tea preparations or a control intervention (matching placebo...

A Chemoprevention Trial to Study the Effects of High Tea Consumption on Smoking-Related Oxidative Stress

National Research Council Canada - National Science Library

Hakim, Iman A

2008-01-01

.... We are conducting a 6-month randomized controlled double-blinded chemopreventive trial in a group of COPD subjects who are being randomized to green or black tea preparations or a control intervention (matching placebo...

Up-regulation of cytochrome P450 and phase II enzyme systems in rat precision-cut rat lung slices by the intact glucosinolates, glucoraphanin and glucoerucin.

Science.gov (United States)

Abdull Razis, Ahmad Faizal; Bagatta, Manuela; De Nicola, Gina Rosalinda; Iori, Renato; Ioannides, Costas

2011-03-01

It is believed that the chemopreventive activity of cruciferous vegetables in the lung and other tissues is exclusively the result of exposure to degradation products of glucosinolates, such as the isothiocyanates, and that the parent glucosinolates make no contribution. In the present study, evidence is presented for the first time that, in rat lung, the intact glucosinolates, glucoraphanin and glucoerucin, can modulate carcinogen-metabolising enzyme systems. The glucosinolates were isolated from cruciferous vegetables and incubated (1-25 μM) with precision-cut rat lung slices for 24h. Both glucosinolates, at concentrations as low as 1 μM, up-regulated the O-deethylation of ethoxyresorufin and the apoprotein levels of CYP1A1 and CYP1B1; supplementation of the incubation medium with myrosinase, the enzyme that converts glucosinolates to their corresponding isothiocyanates, abolished the rise in ethoxyresorufin O-deethylase activity. In contrast, neither glucosinolate, at the concentrations studied, influenced quinone reductase activity in the lung slices, but addition of myrosinase to the glucosinolate incubations led to a marked rise in activity. Glutathione S-transferase activity, monitored using 1-chloro-2,4-dinitrobenzene as the accepting substrate, was elevated in lung slices exposed to glucoraphanin. GSTα protein levels were increased by glucoraphanin and, to a much lesser extent, glucoerucin. It may be concluded that intact glucosinolates can modulate the activity of pulmonary carcinogen-metabolising enzyme systems, and can thus contribute to the documented chemopreventive activity of cruciferous vegetables in the lung. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Chemopreventive effect of chalcone derivative, L2H17, in colon cancer development

International Nuclear Information System (INIS)

Xu, Shanmei; Chen, Minxiao; Chen, Wenbo; Hui, Junguo; Ji, Jiansong; Hu, Shuping; Zhou, Jianmin; Wang, Yi; Liang, Guang

2015-01-01

Colon cancer is the third most commonly diagnosed cancer and the second leading cause of cancer mortality worldwide. Chalcone and its derivatives are reported to exhibit anti-cancer effects in several cancer cell lines, including colon cancer cells. In addition, chalcones have advantages such as poor interaction with DNA and low risk of mutagenesity. In our previous study, a group of chalcone derivatives were synthesized and exhibited strong anti-inflammatory activities. In this study, we evaluated the anti-cancer effects of the chalcone derivative, L2H17, in colon cancer cells. The cytotoxicities of L2H17 on various colon cancer cell lines were investigated by MTT and clonogenic assay. Cell cycle and apoptosis analysis were performed to evaluate the molecular mechanism of L2H17-mediated inhibition of tumor growth. Also, scratch wound and matrigel invasion experiments were performed to estimate the cell migration and invasion after L2H17 treatment. Finally, we observed the anti-colon cancer effects of L2H17 in vivo. Our data show that compound L2H17 exhibited selective cytotoxic effect on colon cancer cells, via inducing G0/G1 cell cycle arrest and apoptosis in CT26.WT cells. Furthermore, L2H17 treatment decreased cell migration and invasion of CT26.WT cells. In addition, L2H17 possessed marked anti-tumor activity in vivo. The molecular mechanism of L2H17-mediated inhibition of tumor promotion and progression were function through inactivated NF-κB and Akt signaling pathways. All these findings show that L2H17 might be a potential growth inhibitory chalcones derivative for colon cancer cells

Potential applications of curcumin and its novel synthetic analogs and nanotechnology-based formulations in cancer prevention and therapy

Directory of Open Access Journals (Sweden)

Batra Surinder K

2011-08-01

Full Text Available Abstract Curcumin has attracted great attention in the therapeutic arsenal in clinical oncology due to its chemopreventive, antitumoral, radiosensibilizing and chemosensibilizing activities against various types of aggressive and recurrent cancers. These malignancies include leukemias, lymphomas, multiple myeloma, brain cancer, melanoma and skin, lung, prostate, breast, ovarian, liver, gastrointestinal, pancreatic and colorectal epithelial cancers. Curcumin mediates its anti-proliferative, anti-invasive and apoptotic effects on cancer cells, including cancer stem/progenitor cells and their progenies, through multiple molecular mechanisms. The oncogenic pathways inhibited by curcumin encompass the members of epidermal growth factor receptors (EGFR and erbB2, sonic hedgehog (SHH/GLIs and Wnt/β-catenin and downstream signaling elements such as Akt, nuclear factor-kappa B (NF-κB and signal transducers and activators of transcription (STATs. In counterbalance, the high metabolic instability and poor systemic bioavailability of curcumin limit its therapeutic efficacy in human. Of great therapeutic interest, the selective delivery of synthetic analogs or nanotechnology-based formulations of curcumin to tumors, alone or in combination with other anticancer drugs, may improve their chemopreventive and chemotherapeutic efficacies against cancer progression and relapse. Novel curcumin formulations may also be used to reverse drug resistance, eradicate the total cancer cell mass and improve the anticarcinogenic efficacy of the current anti-hormonal and chemotherapeutic treatments for patients with various aggressive and lethal cancers.

Reverse screening methods to search for the protein targets of chemopreventive compounds

Science.gov (United States)

Huang, Hongbin; Zhang, Guigui; Zhou, Yuquan; Lin, Chenru; Chen, Suling; Lin, Yutong; Mai, Shangkang; Huang, Zunnan

2018-05-01

This article is a systematic review of reverse screening methods used to search for the protein targets of chemopreventive compounds or drugs. Typical chemopreventive compounds include components of traditional Chinese medicine, natural compounds and Food and Drug Administration (FDA)-approved drugs. Such compounds are somewhat selective but are predisposed to bind multiple protein targets distributed throughout diverse signaling pathways in human cells. In contrast to conventional virtual screening, which identifies the ligands of a targeted protein from a compound database, reverse screening is used to identify the potential targets or unintended targets of a given compound from a large number of receptors by examining their known ligands or crystal structures. This method, also known as in silico or computational target fishing, is highly valuable for discovering the target receptors of query molecules from terrestrial or marine natural products, exploring the molecular mechanisms of chemopreventive compounds, finding alternative indications of existing drugs by drug repositioning, and detecting adverse drug reactions and drug toxicity. Reverse screening can be divided into three major groups: shape screening, pharmacophore screening and reverse docking. Several large software packages, such as Schrödinger and Discovery Studio; typical software/network services such as ChemMapper, PharmMapper, idTarget and INVDOCK; and practical databases of known target ligands and receptor crystal structures, such as ChEMBL, BindingDB and the Protein Data Bank (PDB), are available for use in these computational methods. Different programs, online services and databases have different applications and constraints. Here, we conducted a systematic analysis and multilevel classification of the computational programs, online services and compound libraries available for shape screening, pharmacophore screening and reverse docking to enable non-specialist users to quickly learn and

Both phenolic and non-phenolic green tea fractions inhibit migration of cancer cells

Science.gov (United States)

Green tea consumption is associated with chemoprevention of many cancer types. Fresh tea leaves are rich in polyphenolic catechins, which can constitute up to 30% of the dry leaf weight. While the polyphenols of green tea have been well investigated, it is still largely unknown, whether or not non-p...

Natural ways to prevent and treat oral cancer

Directory of Open Access Journals (Sweden)

Shweta Danaraddi

2014-01-01

Full Text Available Oral cancer is one of the usual causes of mortality all over the world, with a five-year survival rate of only 50%. Oral cancers are treated primarily by surgery with / without adjuvant radiotherapy and / or chemotherapy. However, there is significant post-treatment morbidity and mortality secondary to recurrences. Dietary supplements like fruits and vegetables are rich in phytochemicals and provide a variety of antioxidants like vitamin A, C, E. Spirulina, Selenium, Green tea (EGCG, Neem, Tomatoes (lycopene, Turmeric (curcumin, and some medicinal mushrooms are also used as chemopreventive and chemotherapeutic agents. This overview emphasizes on natural therapies to fight against oral cancer. Thus, there are several natural compounds that can enhance the prevention of oral cancer.

Effects and Costs of Breast Cancer screening in women with a familial or genetic predisposition

NARCIS (Netherlands)

A.J. Rijnsburger (Rian)

2005-01-01

textabstract"Women with a BRCA1 or BRCA2 mutation, who have a considerable increased risk of developing breast cancer, now face the choice of intensive screening, prophylactic surgery or chemoprevention. The efficacy of the various medical options and the durability of its effects are of major

Genetic variants of methyl metabolizing enzymes and epigenetic regulators: Associations with promoter CpG island hypermethylation in colorectal cancer

NARCIS (Netherlands)

Vogel, S. de; Wouters, K.A.D.; Gottschalk, R.W.H.; Schooten, F.J. van; Goeij, A.F.P.M. de; Bruïne, A.P. de; Goldbohm, R.A.; Brandt, P.A. van den; Weijenberg, M.P.; Engeland, M. van

2009-01-01

Aberrant DNA methylation affects carcinogenesis of colorectal cancer. Folate metabolizing enzymes may influence the bioavailability of methyl groups, whereas DNA and histone methyltransferases are involved in epigenetic regulation of gene expression. We studied associations of genetic variants of

Biological Roles of Aberrantly Expressed Glycosphingolipids and Related Enzymes in Human Cancer Development and Progression

Directory of Open Access Journals (Sweden)

Dinghao Zhuo

2018-05-01

Full Text Available Glycosphingolipids (GSLs, which consist of a hydrophobic ceramide backbone and a hydrophilic carbohydrate residue, are an important type of glycolipid expressed in surface membranes of all animal cells. GSLs play essential roles in maintenance of plasma membrane stability, in regulation of numerous cellular processes (including adhesion, proliferation, apoptosis, and recognition, and in modulation of signal transduction pathways. GSLs have traditionally been classified as ganglio-series, lacto-series, or globo-series on the basis of their diverse types of oligosaccharide chains. Structures and functions of specific GSLs are also determined by their oligosaccharide chains. Different cells and tissues show differential expression of GSLs, and changes in structures of GSL glycan moieties occur during development of numerous types of human cancer. Association of GSLs and/or related enzymes with initiation and progression of cancer has been documented in 100s of studies, and many such GSLs are useful markers or targets for cancer diagnosis or therapy. In this review, we summarize (i recent studies on aberrant expression and distribution of GSLs in common human cancers (breast, lung, colorectal, melanoma, prostate, ovarian, leukemia, renal, bladder, gastric; (ii biological functions of specific GSLs in these cancers.

Development of New Treatments for Prostate Cancer

Energy Technology Data Exchange (ETDEWEB)

DiPaola, R. S.; Abate-Shen, C.; Hait, W. N.

2005-02-01

chemoprevention are underway. The specific goals of this program are: (1) To investigate the molecular mechanisms underlying normal prostate growth and differentiation and elucidate the molecular mechanisms underlying prostate oncogenesis. (2) To build on fundamental knowledge to develop effective therapeutic approaches for the treatment of prostate cancer. (3) To improve the control of prostate cancer through early detection, chemoprevention, and outreach and education. This new disease-based program is structured to improve interdisciplinary interactions and translational results. Already, through the dynamic leadership of Drs. Cory Abate-Shen and Robert DiPaola, new investigators were attracted to the field, new collaborations engendered, and numerous investigator-initiated trials implemented. Progress in GPCC and the program overall has been outstanding. The Center has success in uniting investigators with broad and complementary expertise in prostate cancer research. The overall goal and unifying theme is to elucidate basic mechanisms of prostate growth and oncogenesis, with the ultimate goal of promoting new and effective strategies for the eradication of prostate cancer in patients and populations at risk. Members wide range of research interests collectively optimize the chances of providing new insights into normal prostate biology and unraveling the molecular pathophysiology of prostate cancer. Studies in cell culture and powerful animal models developed recapitulate the various stages of prostate cancer progression, including prostatic intraepithelial neoplasia, adenocarcinoma, androgen-independence, invasion and metastases. These models promise to further strengthen an already robust program of investigator-initiated therapeutic clinical trials, including studies adopted by national cooperative groups. Efforts to translate laboratory results into clinical studies of early detection and chemoprevention are underway.

Inhibition of Non-flux-Controlling Enzymes Deters Cancer Glycolysis by Accumulation of Regulatory Metabolites of Controlling Steps.

Science.gov (United States)

Marín-Hernández, Álvaro; Rodríguez-Zavala, José S; Del Mazo-Monsalvo, Isis; Rodríguez-Enríquez, Sara; Moreno-Sánchez, Rafael; Saavedra, Emma

2016-01-01

Glycolysis provides precursors for the synthesis of macromolecules and may contribute to the ATP supply required for the constant and accelerated cellular duplication in cancer cells. In consequence, inhibition of glycolysis has been reiteratively considered as an anti-cancer therapeutic option. In previous studies, kinetic modeling of glycolysis in cancer cells allowed the identification of the main steps that control the glycolytic flux: glucose transporter, hexokinase (HK), hexose phosphate isomerase (HPI), and glycogen degradation in human cervix HeLa cancer cells and rat AS-30D ascites hepatocarcinoma. It was also previously experimentally determined that simultaneous inhibition of the non-controlling enzymes lactate dehydrogenase (LDH), pyruvate kinase (PYK), and enolase (ENO) brings about significant decrease in the glycolytic flux of cancer cells and accumulation of intermediate metabolites, mainly fructose-1,6-bisphosphate (Fru1,6BP), and dihydroxyacetone phosphate (DHAP), which are inhibitors of HK and HPI, respectively. Here it was found by kinetic modeling that inhibition of cancer glycolysis can be attained by blocking downstream non flux-controlling steps as long as Fru1,6BP and DHAP, regulatory metabolites of flux-controlling enzymes, are accumulated. Furthermore, experimental results and further modeling showed that oxamate and iodoacetate inhibitions of PYK, ENO, and glyceraldehyde3-phosphate dehydrogenase (GAPDH), but not of LDH and phosphoglycerate kinase, induced accumulation of Fru1,6BP and DHAP in AS-30D hepatoma cells. Indeed, PYK, ENO, and GAPDH exerted the highest control on the Fru1,6BP and DHAP concentrations. The high levels of these metabolites inhibited HK and HPI and led to glycolytic flux inhibition, ATP diminution, and accumulation of toxic methylglyoxal. Hence, the anticancer effects of downstream glycolytic inhibitors are very likely mediated by this mechanism. In parallel, it was also found that uncompetitive inhibition of the

Lycopene Protects Against Spontaneous Ovarian Cancer Formation in Laying Hens.

Science.gov (United States)

Sahin, Kazim; Yenice, Engin; Tuzcu, Mehmet; Orhan, Cemal; Mizrak, Cengizhan; Ozercan, Ibrahim H; Sahin, Nurhan; Yilmaz, Bahiddin; Bilir, Birdal; Ozpolat, Bulent; Kucuk, Omer

2018-03-01

Dietary intake of lycopene has been associated with a reduced risk of ovarian cancer, suggesting its chemopreventive potential against ovarian carcinogenesis. Lycopene's molecular mechanisms of action in ovarian cancer have not been fully understood. Therefore, in the present study, we investigated the effects of lycopene on the ovarian cancer formation using the laying hen model, a biologically relevant animal model of spontaneous ovarian carcinogenesis due to high incidence rates similar to humans. In this study, a total of 150 laying hens at age of 102 weeks were randomized into groups of 50: a control group (0 mg of lycopene per kg of diet) and two treatment groups (200 mg or 400 mg of lycopene per kg of diet, or ~26 and 52 mg/d/hen, respectively). At the end of 12 months, blood, ovarian tissues and tumors were collected. We observed that lycopene supplementation significantly reduced the overall ovarian tumor incidence ( P Lycopene also significantly decreased the rate of adenocarcinoma, including serous and mucinous subtypes ( P lycopene-fed hens compared to control birds ( P lycopene reduced the expression of NF-κB while increasing the expression of nuclear factor erythroid 2 and its major target protein, heme oxygenase 1. In addition, lycopene supplementation decreased the expression of STAT3 by inducing the protein inhibitor of activated STAT3 expression in the ovarian tissues. Taken together, our findings strongly support the potential of lycopene in the chemoprevention of ovarian cancer through antioxidant and anti-inflammatory mechanisms.

Can transcriptomics provide insight into the underlying chemopreventive mechanisms of complex mixtures of phytochemicals in humans?

NARCIS (Netherlands)

Breda, van S.G.; Wilms, L.C.; Gaj, S.; Briedé, J.J.; Helsper, J.P.F.G.; Kleinjans, J.C.; Kok, de T.M.

2014-01-01

Blueberries contain relatively large amounts of different phytochemicals which are suggested to have chemopreventive properties, but little information is available on the underlying molecular modes of action. This study investigates whole genome gene expression changes in lymphocytes of 143 humans

Chemopreventive effect of artesunate in 1,2-dimethylhydrazine-induced rat colon carcinogenesis

Directory of Open Access Journals (Sweden)

Sazal Patyar

2017-01-01

Full Text Available Artesunate (ART is a semisynthetic derivative of artemisinin. Artemisinin and its derivatives have shown profound cytotoxicity and antitumor activity in addition to antimalarial activity in various studies. As the in vivo chemopreventive efficacy of ART in colon carcinogenesis has not been investigated so far, the aim of the current study was to study the chemopreventive effect of ART in 1,2-dimethylhydrazine (DMH-induced rat colon carcinogenesis. Animals were divided into four groups (n = 6: Group I - vehicle (1 mM ethylenediaminetetraacetic acid, Group II - DMH (20 mg/kg, Group III - DMH + 5-fluorouracil (81 mg/kg, Group IV - DMH + ART (6.7 mg/kg. After completion of 15 weeks of treatment, rats were sacrificed under ether anesthesia by cervical dislocation for assessment of lipid peroxidation (LPO, antioxidant status, average number of aberrant crypt foci (ACF, and cytokine levels. ART administration significantly decreased the average number of ACF/microscopic field. Similarly, LPO level was decreased and antioxidant activities were enhanced after ART treatment. ART decreased the levels of proinflammatory cytokines and induced apoptosis in the colons of DMH-treated rats. The results of this study suggest that ART has a beneficial effect against chemically induced colonic preneoplastic progression in rats.

Trial endpoints for drug approval in oncology: Chemoprevention.

Science.gov (United States)

Beitz, J

2001-04-01

As with other drugs, new drug applications for marketing approval of chemopreventive drugs must include data from adequate and well-controlled clinical trials that demonstrate effectiveness and safety for the intended use. This article summarizes the regulatory requirements for traditional marketing approval, as well as for approval under the accelerated approval regulations. Unlike traditional approval, accelerated approval is based on a surrogate endpoint that is reasonably likely to predict clinical benefit. Discussions with the Food and Drug Administration (FDA) regarding the validity of trial endpoints that may serve as surrogates for clinical benefit for accelerated approval should take place as early as possible in drug development. Meetings with the FDA to discuss these issues may be requested throughout the clinical development of a new drug.

High-polyphenol sorghum bran extract inhibits cancer cell growth through DNA damage, cell cycle arrest, and apoptosis

Science.gov (United States)

As diet is one of the major controllable factors in cancer development, potentially chemopreventive foods are of significant interest to public health. One such food is sorghum (Sorghum bicolor), a cereal grain that contains varying concentrations of polyphenols. In a panel of 15 sorghum germplasm...

Beta-endorphin Cell Therapy for Cancer Prevention

OpenAIRE

Zhang, Changqing; Murugan, Sengottuvelan; Boyadjieva, Nadka; Jabbar, Shaima; Shrivastava, Pallavi; Sarkar, Dipak K.

2014-01-01

Beta-endorphin (BEP) producing neuron in the hypothalamus plays a key role in brining the stress axis to a state of homeostasis and maintaining body immune defense system. Long-term delivery of BEP to obtain beneficial effect on chemoprevention is challenging, since the peptide rapidly develop tolerance. Using rats as animal model, we show here that transplantation of beta-endorphin neurons into the hypothalamus suppressed carcinogens- and hormone-induced cancers in various tissues and preven...

Novel β-lactamase-random peptide fusion libraries for phage display selection of cancer cell-targeting agents suitable for enzyme prodrug therapy

Science.gov (United States)

Shukla, Girja S.; Krag, David N.

2010-01-01

Novel phage-displayed random linear dodecapeptide (X12) and cysteine-constrained decapeptide (CX10C) libraries constructed in fusion to the amino-terminus of P99 β-lactamase molecules were used for identifying β-lactamase-linked cancer cell-specific ligands. The size and quality of both libraries were comparable to the standards of other reported phage display systems. Using the single-round panning method based on phage DNA recovery, we identified severalβ-lactamase fusion peptides that specifically bind to live human breast cancer MDA-MB-361 cells. The β-lactamase fusion to the peptides helped in conducting the enzyme activity-based clone normalization and cell-binding screening in a very time- and cost-efficient manner. The methods were suitable for 96-well readout as well as microscopic imaging. The success of the biopanning was indicated by the presence of ~40% cancer cell-specific clones among recovered phages. One of the binding clones appeared multiple times. The cancer cell-binding fusion peptides also shared several significant motifs. This opens a new way of preparing and selecting phage display libraries. The cancer cell-specific β-lactamase-linked affinity reagents selected from these libraries can be used for any application that requires a reporter for tracking the ligand molecules. Furthermore, these affinity reagents have also a potential for their direct use in the targeted enzyme prodrug therapy of cancer. PMID:19751096

Differential 3-bromopyruvate inhibition of cytosolic and mitochondrial human serine hydroxymethyltransferase isoforms, key enzymes in cancer metabolic reprogramming.

Science.gov (United States)

Paiardini, Alessandro; Tramonti, Angela; Schirch, Doug; Guiducci, Giulia; di Salvo, Martino Luigi; Fiascarelli, Alessio; Giorgi, Alessandra; Maras, Bruno; Cutruzzolà, Francesca; Contestabile, Roberto

2016-11-01

The cytosolic and mitochondrial isoforms of serine hydroxymethyltransferase (SHMT1 and SHMT2, respectively) are well-recognized targets of cancer research, since their activity is critical for purine and pyrimidine biosynthesis and because of their prominent role in the metabolic reprogramming of cancer cells. Here we show that 3-bromopyruvate (3BP), a potent novel anti-tumour agent believed to function primarily by blocking energy metabolism, differentially inactivates human SHMT1 and SHMT2. SHMT1 is completely inhibited by 3BP, whereas SHMT2 retains a significant fraction of activity. Site directed mutagenesis experiments on SHMT1 demonstrate that selective inhibition relies on the presence of a cysteine residue at the active site of SHMT1 (Cys204) that is absent in SHMT2. Our results show that 3BP binds to SHMT1 active site, forming an enzyme-3BP complex, before reacting with Cys204. The physiological substrate l-serine is still able to bind at the active site of the inhibited enzyme, although catalysis does not occur. Modelling studies suggest that alkylation of Cys204 prevents a productive binding of l-serine, hampering interaction between substrate and Arg402. Conversely, the partial inactivation of SHMT2 takes place without the formation of a 3BP-enzyme complex. The introduction of a cysteine residue in the active site of SHMT2 by site directed mutagenesis (A206C mutation), at a location corresponding to that of Cys204 in SHMT1, yields an enzyme that forms a 3BP-enzyme complex and is completely inactivated. This work sets the basis for the development of selective SHMT1 inhibitors that target Cys204, starting from the structure and reactivity of 3BP. Copyright © 2016 Elsevier B.V. All rights reserved.

[6]-Gingerol induces caspase-dependent apoptosis and prevents PMA-induced proliferation in colon cancer cells by inhibiting MAPK/AP-1 signaling.

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E K Radhakrishnan

Full Text Available We report mechanism-based evidence for the anticancer and chemopreventive efficacy of [6]-gingerol, the major active principle of the medicinal plant, Ginger (Zingiber officinale, in colon cancer cells. The compound was evaluated in two human colon cancer cell lines for its cytotoxic effect and the most sensitive cell line, SW-480, was selected for the mechanistic evaluation of its anticancer and chemopreventive efficacy. The non-toxic nature of [6]-gingerol was confirmed by viability assays on rapidly dividing normal mouse colon cells. [6]-gingerol inhibited cell proliferation and induced apoptosis as evidenced by externalization of phosphatidyl serine in SW-480, while the normal colon cells were unaffected. Sensitivity to [6]-gingerol in SW-480 cells was associated with activation of caspases 8, 9, 3 &7 and cleavage of PARP, which attests induction of apoptotic cell death. Mechanistically, [6]-gingerol down-regulated Phorbol Myristate Acetate (PMA induced phosphorylation of ERK1/2 and JNK MAP kinases and activation of AP-1 transcription factor, but had only little effects on phosphorylation of p38 MAP kinase and activation of NF-kappa B. Additionally, it complemented the inhibitors of either ERK1/2 or JNK MAP kinase in bringing down the PMA-induced cell proliferation in SW-480 cells. We report the inhibition of ERK1/2/JNK/AP-1 pathway as a possible mechanism behind the anticancer as well as chemopreventive efficacy of [6]-gingerol against colon cancer.

The ubiquitin-conjugating enzyme E2-EPF is overexpressed in cervical cancer and associates with tumor growth.

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Liang, Jing; Nishi, Hirotaka; Bian, Mei-Lu; Higuma, Chinatsu; Sasaki, Toru; Ito, Hiroe; Isaka, Keiichi

2012-10-01

We found that the ubiquitin-conjugating enzyme E2-EPF mRNA is highly expressed in cervical squamous cancer relative to normal tissues and its expression levels positively correlate with clinical stage. Reduction of E2-EPF protein levels by >80% using shRNA decreases the expression levels of HIF-1α, and the proliferation, invasion and tumorigenicity of SiHa, a cervical squamous cancer cell line. E2-EPF knockdown also increases the chemosensitivity to topoisomerase I inhibitor (topotecan) and II (etoposide and doxorubicin). Our results suggest that E2-EPF is associated with the growth and aggressivity of cervical tumor cells. Targeting the E2-EPF pathway may have potential clinical applications for the treatment of cervical cancer.

Kaempferol nanoparticles achieve strong and selective inhibition of ovarian cancer cell viability

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Luo, Haitao; Jiang, Bingbing; Li, Bingyun; Li, Zhaoliang; Jiang, Bing-Hua; Chen, Yi Charlie

2012-01-01

Ovarian cancer is one of the leading causes of cancer death for women throughout the Western world. Kaempferol, a natural flavonoid, has shown promise in the chemoprevention of ovarian cancer. A common concern about using dietary supplements for chemoprevention is their bioavailability. Nanoparticles have shown promise in increasing the bioavailability of some chemicals. Here we developed five different types of nanoparticles incorporating kaempferol and tested their efficacy in the inhibition of viability of cancerous and normal ovarian cells. We found that positively charged nanoparticle formulations did not lead to a significant reduction in cancer cell viability, whereas nonionic polymeric nanoparticles resulted in enhanced reduction of cancer cell viability. Among the nonionic polymeric nanoparticles, poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) nanoparticles incorporating kaempferol led to significant reduction in cell viability of both cancerous and normal cells. Poly(DL-lactic acid-co-glycolic acid) (PLGA) nanoparticles incorporating kaempferol resulted in enhanced reduction of cancer cell viability together with no significant reduction in cell viability of normal cells compared with kaempferol alone. Therefore, both PEO-PPO-PEO and PLGA nanoparticle formulations were effective in reducing cancer cell viability, while PLGA nanoparticles incorporating kaempferol had selective toxicity against cancer cells and normal cells. A PLGA nanoparticle formulation could be advantageous in the prevention and treatment of ovarian cancers. On the other hand, PEO-PPO-PEO nanoparticles incorporating kaempferol were more effective inhibitors of cancer cells, but they also significantly reduced the viability of normal cells. PEO-PPO-PEO nanoparticles incorporating kaempferol may be suitable as a cancer-targeting strategy, which could limit the effects of the nanoparticles on normal cells while retaining their potency against cancer cells. We

Selenium and Prostate Cancer Prevention: Insights from the Selenium and Vitamin E Cancer Prevention Trial (SELECT)

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Nicastro, Holly L.; Dunn, Barbara K.

2013-01-01

The Selenium and Vitamin E Cancer Prevention Trial (SELECT) was conducted to assess the efficacy of selenium and vitamin E alone, and in combination, on the incidence of prostate cancer. This randomized, double-blind, placebo-controlled, 2 × 2 factorial design clinical trial found that neither selenium nor vitamin E reduced the incidence of prostate cancer after seven years and that vitamin E was associated with a 17% increased risk of prostate cancer compared to placebo. The null result was surprising given the strong preclinical and clinical evidence suggesting chemopreventive activity of selenium. Potential explanations for the null findings include the agent formulation and dose, the characteristics of the cohort, and the study design. It is likely that only specific subpopulations may benefit from selenium supplementation; therefore, future studies should consider the baseline selenium status of the participants, age of the cohort, and genotype of specific selenoproteins, among other characteristics, in order to determine the activity of selenium in cancer prevention. PMID:23552052

Selenium and Prostate Cancer Prevention: Insights from the Selenium and Vitamin E Cancer Prevention Trial (SELECT

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Holly L. Nicastro

2013-04-01

Full Text Available The Selenium and Vitamin E Cancer Prevention Trial (SELECT was conducted to assess the efficacy of selenium and vitamin E alone, and in combination, on the incidence of prostate cancer. This randomized, double-blind, placebo-controlled, 2 × 2 factorial design clinical trial found that neither selenium nor vitamin E reduced the incidence of prostate cancer after seven years and that vitamin E was associated with a 17% increased risk of prostate cancer compared to placebo. The null result was surprising given the strong preclinical and clinical evidence suggesting chemopreventive activity of selenium. Potential explanations for the null findings include the agent formulation and dose, the characteristics of the cohort, and the study design. It is likely that only specific subpopulations may benefit from selenium supplementation; therefore, future studies should consider the baseline selenium status of the participants, age of the cohort, and genotype of specific selenoproteins, among other characteristics, in order to determine the activity of selenium in cancer prevention.

Association between single nucleotide polymorphisms in the antioxidant genes CAT, GR and SOD1, erythrocyte enzyme activities, dietary and life style factors and breast cancer risk in a Danish, prospective cohort study

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Kopp, Tine Iskov; Vogel, Ulla; Dragsted, Lars Ove

2017-01-01

investigated in 703 breast cancer case-control pairs in the Danish, prospective "Diet, Cancer and Health" cohort together with gene-environment interactions between the polymorphisms, enzyme activities and intake of fruits and vegetables, alcohol and smoking in relation to breast cancer risk. Our results...... showed that genetically determined variations in the antioxidant enzyme activities of SOD1, CAT and GSR were not associated with risk of breast cancer per se. However, intake of alcohol, fruit and vegetables, and smoking status interacted with some of the polymorphisms in relation to breast cancer risk...

Targeting multiple pro-apoptotic signaling pathways with curcumin in prostate cancer cells.

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Mariela Rivera

Full Text Available Curcumin, an extract from the turmeric rhizome (Curcuma longa, is known to exhibit anti-inflammatory, antioxidant, chemopreventive and antitumoral activities against aggressive and recurrent cancers. Accumulative data indicate that curcumin may induce cancer cell death. However, the detailed mechanism underlying its pro-apoptotic and anti-cancer effects remains to be elucidated. In the present study, we examined the signaling pathways triggered by curcumin, specifically, the exact molecular mechanisms of curcumin-induced apoptosis in highly metastatic human prostate cancer cells. The effect of curcumin was evaluated using for the first time in prostate cancer, a gel-free shotgun quantitative proteomic analysis coupled with Tandem Mass Tag isobaric labeling-based-signaling networks. Results were confirmed at the gene expression level by qRT-PCR and at the protein expression level by western blot and flow cytometry. Our findings revealed that curcumin induced an Endoplasmic Reticulum stress-mediated apoptosis in PC3. The mechanisms by which curcumin promoted cell death in these cells were associated with cell cycle arrest, increased reactive oxygen species, autophagy and the Unfolded Protein Response. Furthermore, the upregulation of ER stress was measured using key indicators of ER stress: Glucose-Regulated Protein 78, Inositol-Requiring Enzyme 1 alpha, Protein Disulfide isomerase and Calreticulin. Chronic ER stress induction was concomitant with the upregulation of pro-apoptotic markers (caspases 3,9,12 and Poly (ADP-ribose polymerase. The downregulated proteins include anti-apoptotic and anti-tumor markers, supporting their curcumin-induced pro-apoptotic role in prostate cancer cells. Taken together, these data suggest that curcumin may serve as a promising anticancer agent by inducing a chronic ER stress mediated cell death and activation of cell cycle arrest, UPR, autophagy and oxidative stress responses.

Targeting multiple pro-apoptotic signaling pathways with curcumin in prostate cancer cells

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Rivera, Mariela; Ramos, Yanilda; Rodríguez-Valentín, Madeline; López-Acevedo, Sheila; Cubano, Luis A.; Zou, Jin; Zhang, Qiang; Wang, Guangdi

2017-01-01

Curcumin, an extract from the turmeric rhizome (Curcuma longa), is known to exhibit anti-inflammatory, antioxidant, chemopreventive and antitumoral activities against aggressive and recurrent cancers. Accumulative data indicate that curcumin may induce cancer cell death. However, the detailed mechanism underlying its pro-apoptotic and anti-cancer effects remains to be elucidated. In the present study, we examined the signaling pathways triggered by curcumin, specifically, the exact molecular mechanisms of curcumin-induced apoptosis in highly metastatic human prostate cancer cells. The effect of curcumin was evaluated using for the first time in prostate cancer, a gel-free shotgun quantitative proteomic analysis coupled with Tandem Mass Tag isobaric labeling-based-signaling networks. Results were confirmed at the gene expression level by qRT-PCR and at the protein expression level by western blot and flow cytometry. Our findings revealed that curcumin induced an Endoplasmic Reticulum stress-mediated apoptosis in PC3. The mechanisms by which curcumin promoted cell death in these cells were associated with cell cycle arrest, increased reactive oxygen species, autophagy and the Unfolded Protein Response. Furthermore, the upregulation of ER stress was measured using key indicators of ER stress: Glucose-Regulated Protein 78, Inositol-Requiring Enzyme 1 alpha, Protein Disulfide isomerase and Calreticulin. Chronic ER stress induction was concomitant with the upregulation of pro-apoptotic markers (caspases 3,9,12) and Poly (ADP-ribose) polymerase. The downregulated proteins include anti-apoptotic and anti-tumor markers, supporting their curcumin-induced pro-apoptotic role in prostate cancer cells. Taken together, these data suggest that curcumin may serve as a promising anticancer agent by inducing a chronic ER stress mediated cell death and activation of cell cycle arrest, UPR, autophagy and oxidative stress responses. PMID:28628644

Lipid-based oral delivery systems for skin deposition of a potential chemopreventive DIM derivative: characterization and evaluation.

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Boakye, Cedar H A; Patel, Ketan; Patel, Apurva R; Faria, Henrique A M; Zucolotto, Valtencir; Safe, Stephen; Singh, Mandip

2016-10-01

The objective of this study was to explore the oral route as a viable potential for the skin deposition of a novel diindolylmethane derivative (DIM-D) for chemoprevention activity. Various lipid-based oral delivery systems were optimized and compared for enhancing DIM-D's oral bioavailability and skin deposition. Preformulation studies were performed to evaluate the log P and solubility of DIM-D. Microsomal metabolism, P-glycoprotein efflux, and caco-2 monolayer permeability of DIM-D were determined. Comparative evaluation of the oral absorption and skin deposition of DIM-D-loaded various lipid-based formulations was performed in rats. DIM-D showed pH-dependent solubility and a high log P value. It was not a strong substrate of microsomal degradation and P-glycoprotein. SMEDDs comprised of medium chain triglycerides, monoglycerides, and kolliphor-HS15 (36.70 ± 0.42 nm). SNEDDs comprised of long chain triglycerides, cremophor RH40, labrasol, and TPGS (84.00 ± 14.14 nm). Nanostructured lipid carriers (NLC) consisted of compritol, miglyol, and surfactants (116.50 ± 2.12 nm). The blank formulations all showed >70 % cell viability in caco-2 cells. Differential Scanning Calorimetry confirmed the amorphization of DIM-D within the lipid matrices while Atomic Force Microscopy showed particle size distribution similar to the dynamic light scattering data. DIM-D also showed reduced permeation across caco-2 monolayer that was enhanced (p < 0.05) by SNEDDs in comparison to SMEDDs and NLC. Fabsolute for DIM-D SNEDDs, SMEDDs, and NLC was 0.14, 0.04, and 0.007, respectively. SNEDDs caused 53.90, 11.32, and 15.08-fold more skin deposition of DIM-D than the free drug, SMEDDs, and NLC, respectively, at 2 h following oral administration and shows a viable potential for use in skin cancer chemoprevention. Graphical Abstract ᅟ.

A review of the dietary flavonoid, kaempferol on human health and cancer chemoprevention

OpenAIRE

Chen, Allen Y.; Chen, Yi Charlie

2012-01-01

Kaempferol is a polyphenol antioxidant found in fruits and vegetables. Many studies have described the beneficial effects of dietary kaempferol in reducing the risk of chronic diseases, especially cancer. Epidemiological studies have shown an inverse relationship between kaempferol intake and cancer. Kaempferol may help by augmenting the body’s antioxidant defense against free radicals, which promote the development of cancer. At the molecular level, kaempferol has been reported to modulate a...

The relevance of piroxicam for the prevention and treatment of nonmelanoma skin cancer and its precursors

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Campione E

2015-10-01

Full Text Available Elena Campione,1 Evelin Jasmine Paternò,2 Eleonora Candi,3,4 Mattia Falconi,5 Gaetana Costanza,2 Laura Diluvio,1 Alessandro Terrinoni,4 Luca Bianchi,1 Augusto Orlandi2,6,7 1Department of Dermatology, 2Department of Biomedicine and Prevention, 3Department of Experimental Medicine and Surgery, University of Rome “Tor Vergata”, 4Biochemistry Laboratory IDI-IRCCS, Faculty of Medicine, University of Rome “Tor Vergata”, 5Department of Biology, University of Rome “Tor Vergata”, 6Institute of Anatomic Pathology, University of Rome “Tor Vergata”, 7Tor Vergata University-Policlinic of Rome, Rome, Italy Abstract: Piroxicam (PXM, a nonsteroidal anti-inflammatory drug, is an enolic benzothiazine and a potent member of the oxicam series. The drug suppresses the synthesis of proinflammatory enzymes, such as cyclooxygenases-1 and -2 (COX-1 and 2, downregulates the production of prostaglandins (PGs and tromboxanes, and inhibits polyamines production by blocking ornithine decarboxylase induction involved in nonmelanoma skin carcinogenesis. In addition, PXM is able to induce tumor cell apoptosis and suppresses metalloproteinase 2 activities. Skin carcinogenesis is a multistep process in which the accumulation of genetic events leads to a gradually dysplastic cellular expression, deregulation of cell growth, and carcinomatous progression. COX-1 upregulation plays a significant role in PG and vascular epidermal growth factor production supporting tumor growth. Increased level of PGs in premalignant and/or malignant cutaneous tumors is also favored by upregulation of COX-2 and downregulation of the tumor suppressor gene 15-hydroxy-prostaglandin dehydrogenase. Chemoprevention can be a hopeful approach to inhibit carcinoma occurrence before an invasive tumor develops. The chemopreventive effect of nonsteroidal anti-inflammatory drugs on nonmelanoma skin cancers has been established. In this study, we highlighted the different modalities of action

Chemoprevention of Breast Cancer by Mimicking the Protective Effect of Early First Birth. Addendum

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2013-03-01

Ig lambda-1 chain C region 363828 Immunoglobulin Immune 1.5 1.4 1.4 1.3 1.4 Malic enzyme 1 Me1 24552 Pyruvate synthesis Metabolism 1.3 1.4 1.4 1.1...1.3 biosynthesis Differentation Malic enzyme 1 Me1 24552 Pyruvate synthesis Metabolism 1.3 1.4 1.4 1.1 1.3 Phosphodiesterase 4B Pde4b 24626 cAMP...Contraception 86 (2012) 238–243dense breast tissue in the upper-outer quadrant of the breast. After anesthetizing the breast with 1% lidocaine , a 4-mm

Cross-species global and subset gene expression profiling identifies genes involved in prostate cancer response to selenium

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Dhir Rajiv

2004-08-01

Full Text Available Abstract Background Gene expression technologies have the ability to generate vast amounts of data, yet there often resides only limited resources for subsequent validation studies. This necessitates the ability to perform sorting and prioritization of the output data. Previously described methodologies have used functional pathways or transcriptional regulatory grouping to sort genes for further study. In this paper we demonstrate a comparative genomics based method to leverage data from animal models to prioritize genes for validation. This approach allows one to develop a disease-based focus for the prioritization of gene data, a process that is essential for systems that lack significant functional pathway data yet have defined animal models. This method is made possible through the use of highly controlled spotted cDNA slide production and the use of comparative bioinformatics databases without the use of cross-species slide hybridizations. Results Using gene expression profiling we have demonstrated a similar whole transcriptome gene expression patterns in prostate cancer cells from human and rat prostate cancer cell lines both at baseline expression levels and after treatment with physiologic concentrations of the proposed chemopreventive agent Selenium. Using both the human PC3 and rat PAII prostate cancer cell lines have gone on to identify a subset of one hundred and fifty-four genes that demonstrate a similar level of differential expression to Selenium treatment in both species. Further analysis and data mining for two genes, the Insulin like Growth Factor Binding protein 3, and Retinoic X Receptor alpha, demonstrates an association with prostate cancer, functional pathway links, and protein-protein interactions that make these genes prime candidates for explaining the mechanism of Selenium's chemopreventive effect in prostate cancer. These genes are subsequently validated by western blots showing Selenium based induction and using

Assessing barriers to a rational chemoprevention trial design in young patients with familial adenomatous polyposis.

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Wood, Joanna P; Howells, Lynne M; Brown, Karen; Thomas, Anne L

2017-07-01

Familial adenomatous polyposis coli (FAP) is an autosomal dominant condition caused by a germline mutation in the adenomatous polyposis coli gene. Colonic adenomas form and almost all patients will develop colorectal cancer if they are not managed at an early stage. The safest preventive strategy is surgical resection of the colon, most commonly performed in late teenage years. There is a paucity of trials investigating the use of primary chemoprevention to delay polyp formation in paediatric FAP. There are extensive preclinical and early clinical data demonstrating that curcumin may be a safe and effective chemotherapeutic agent in reducing the polyp burden in this disease. We ultimately proposed to design and conduct a clinical study to assess whether curcumin treatment delays the need for surgery and/or prevents cancer in young patients with FAP. Research into clinical trial protocols has demonstrated that assessing patients' perceptions at the initial stage leads to better outcomes. We therefore conducted a questionnaire study of patients and parents of children affected by FAP to gain information to aid the protocol design. Results demonstrated that there are some FAP patients for whom this study is relevant and desirable. Those with a personal history of curcumin use reported that it was well tolerated. However, the response rate was poor (25%), indicating that there are potential difficulties ensuring adequate recruitment to the proposed trial. This report draws on lessons learnt from prior trials and the findings from the questionnaire to outline the challenges faced in designing such a study.

Dietary compounds that induce cancer preventive phase 2 enzymes activate apoptosis at comparable doses in HT29 colon carcinoma cells.

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Kirlin, W G; Cai, J; DeLong, M J; Patten, E J; Jones, D P

1999-10-01

Dietary agents that induce glutathione S-transferases and related detoxification systems (Phase 2 enzyme inducers) are thought to prevent cancer by enhancing elimination of chemical carcinogens. The present study shows that compounds of this group (benzyl isothiocyanate, allyl sulfide, dimethyl fumarate, butylated hydroxyanisole) activated apoptosis in human colon carcinoma (HT29) cells in culture over the same concentration ranges that elicited increases in enzyme activity (5-25, 25-100, 10-100, 15-60 micromol/L, respectively). Pretreatment of cells with sodium butyrate, an agent that induces HT29 cell differentiation, resulted in parallel increases in Phase 2 enzyme activities and induction of apoptosis in response to the inducers. Cell death characteristics included apoptotic morphological changes, appearance of cells at sub-G1 phase on flow cytometry, caspase activation, DNA fragmentation and TUNEL-positive staining. The results suggest that dietary Phase 2 inducers may protect against cancer by a mechanism distinct from and in addition to that associated with enhanced elimination of carcinogens. If this occurs in vivo, diets high in such compounds could eliminate precancerous cells by apoptosis at time points well after initial exposure to chemical mutagens and carcinogens.

Failure of Chemotherapy in Hepatocellular Carcinoma Due to Impaired and Dysregulated Primary Liver Drug Metabolizing Enzymes and Drug Transport Proteins: What to Do?

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Ul Islam, Salman; Ahmed, Muhammad Bilal; Shehzad, Adeeb; Ul-Islam, Mazhar; Lee, Young Sup

2018-05-28

Most of the drugs are metabolized in the liver by the action of drug metabolizing enzymes. In hepatocellular carcinoma (HCC), primary drug metabolizing enzymes are severely dysregulated, leading to failure of chemotherapy. Sorafenib is the only standard systemic drug available, but it still presents certain limitations, and much effort is required to understand who is responsive and who is refractory to the drug. Preventive and therapeutic approaches other than systemic chemotherapy include vaccination, chemoprevention, liver transplantation, surgical resection, and locoregional therapies. This review details the dysregulation of primary drug metabolizing enzymes and drug transport proteins of the liver in HCC and their influence on chemotherapeutic drugs. Furthermore, it emphasizes the adoption of safe alternative therapeutic strategies to chemotherapy. The future of HCC treatment should emphasize the understanding of resistance mechanisms and the finding of novel, safe, and efficacious therapeutic strategies, which will surely benefit patients affected by advanced HCC. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Novel vitamin D compounds and skin cancer prevention

OpenAIRE

Tongkao-on, Wannit; Gordon-Thomson, Clare; Dixon, Katie M.; Song, Eric J.; Luu, Tan; Carter, Sally E.; Sequeira, Vanessa B.; Reeve, Vivienne E.; Mason, Rebecca S.

2013-01-01

As skin cancer is one of the most costly health issues in many countries, particularly in Australia, the possibility that vitamin D compounds might contribute to prevention of this disease is becoming increasingly more attractive to researchers and health communities. In this article, important epidemiologic, mechanistic and experimental data supporting the chemopreventive potential of several vitamin D-related compounds are explored. Evidence of photoprotection by the active hormone, 1α,25di...

Epigenetic effects of green tea polyphenols in cancer

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Henning, Susanne M; Wang, Piwen; Carpenter, Catherine L; Heber, David

2014-01-01

Epigenetics describes heritable alterations of gene expression and chromatin organization without changes in DNA sequence. Both hypermethylation and hypomethylation of DNA can affect gene expression and the multistep process of carcinogenesis. Epigenetic changes are reversible and may be targeted by dietary interventions. Bioactive compounds from green tea (GT) such as (–)-epigallocatechin gallate have been shown to alter DNA methyltransferase activity in studies of esophageal, oral, skin, Tregs, lung, breast and prostate cancer cells, which may contribute to the chemopreventive effect of GT. Three out of four mouse model studies have confirmed the inhibitory effect of (–)-epigallocatechin gallate on DNA methylation. A human study demonstrated that decreased methylation of CDX2 and BMP-2 in gastric carcinoma was associated with higher GT consumption. It is the goal of this review to summarize our current knowledge of the potential of GT to alter epigenetic processes, which may be useful in chemoprevention. PMID:24283885

Asbestos Induces Oxidative Stress and Activation of Nrf2 Signaling in Murine Macrophages: Chemopreventive Role of the Synthetic Lignan Secoisolariciresinol Diglucoside (LGM2605

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Ralph A. Pietrofesa

2016-03-01

Full Text Available The interaction of asbestos fibers with macrophages generates harmful reactive oxygen species (ROS and subsequent oxidative cell damage that are key processes linked to malignancy. Secoisolariciresinol diglucoside (SDG is a non-toxic, flaxseed-derived pluripotent compound that has antioxidant properties and may thus function as a chemopreventive agent for asbestos-induced mesothelioma. We thus evaluated synthetic SDG (LGM2605 in asbestos-exposed, elicited murine peritoneal macrophages as an in vitro model of tissue phagocytic response to the presence of asbestos in the pleural space. Murine peritoneal macrophages (MFs were exposed to crocidolite asbestos fibers (20 µg/cm2 and evaluated at various times post exposure for cytotoxicity, ROS generation, malondialdehyde (MDA, and levels of 8-iso Prostaglandin F2α (8-isoP. We then evaluated the ability of LGM2605 to mitigate asbestos-induced oxidative stress by administering LGM2605 (50 µM 4-h prior to asbestos exposure. We observed a significant (p < 0.0001, time-dependent increase in asbestos-induced cytotoxicity, ROS generation, and the release of MDA and 8-iso Prostaglandin F2α, markers of lipid peroxidation, which increased linearly over time. LGM2605 treatment significantly (p < 0.0001 reduced asbestos-induced cytotoxicity and ROS generation, while decreasing levels of MDA and 8-isoP by 71%–88% and 41%–73%, respectively. Importantly, exposure to asbestos fibers induced cell protective defenses, such as cellular Nrf2 activation and the expression of phase II antioxidant enzymes, HO-1 and Nqo1 that were further enhanced by LGM2605 treatment. LGM2605 boosted antioxidant defenses, as well as reduced asbestos-induced ROS generation and markers of oxidative stress in murine peritoneal macrophages, supporting its possible use as a chemoprevention agent in the development of asbestos-induced malignant mesothelioma.

Identification of an unintended consequence of Nrf2-directed cytoprotection against a key tobacco carcinogen plus a counteracting chemopreventive intervention

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Paonessa, Joseph D.; Ding, Yi; Randall, Kristen L.; Munday, Rex; Argoti, Dayana; Vouros, Paul; Zhang, Yuesheng

2011-01-01

Nrf2 is a major cytoprotective gene and is a key chemopreventive target against cancer and other diseases. Here we show that Nrf2 faces a dilemma in defense against 4-aminobiphenyl (ABP), a major human bladder carcinogen from tobacco smoke and other environmental sources. While Nrf2 protected mouse liver against ABP (which is metabolically activated in liver), the bladder level of N-(deoxyguanosin-8-yl)-4-aminobiphenyl (dG-C8-ABP), the predominant ABP-DNA adduct formed in bladder cells and tissues, was markedly higher in Nrf2+/+ mice than in Nrf2−/− mice after ABP exposure. Notably, Nrf2 protected bladder cells against ABP in vitro. Mechanistic investigations showed that the dichotomous effects of Nrf2 could be explained at least partly by upregulation of UDP-glucuronosyltransferase (UGT). Nrf2 promoted conjugation of ABP with glucuronic acid in the liver, increasing urinary excretion of the conjugate. While glucuronidation of ABP and its metabolites is a detoxification process, these conjugates, which are excreted in urine, are known to be unstable in acidic urine, leading to delivery of the parent compounds to bladder. Hence, while higher liver UGT activity may protect the liver against ABP it increases bladder exposure to ABP. These findings raise concerns of potential bladder toxicity when Nrf2-activating chemopreventive agents are used in humans exposed to ABP, especially in smokers. We further demonstrate that 5,6-dihydrocyclopenta[c][1,2]-dithiole-3(4H)-thione (CPDT) significantly inhibits dG-C8-ABP formation in bladder cells and tissues, but does not appear to significantly modulate ABP-catalyzing UGT in liver. Thus, CPDT exemplifies a counteracting solution to the dilemma posed by Nrf2. PMID:21487034

Selenium and Lung Cancer: A Systematic Review and Meta Analysis

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Fritz, Heidi; Kennedy, Deborah; Fergusson, Dean; Fernandes, Rochelle; Cooley, Kieran; Seely, Andrew; Sagar, Stephen; Wong, Raimond; Seely, Dugald

2011-01-01

Background Selenium is a natural health product widely used in the treatment and prevention of lung cancers, but large chemoprevention trials have yielded conflicting results. We conducted a systematic review of selenium for lung cancers, and assessed potential interactions with conventional therapies. Methods and Findings Two independent reviewers searched six databases from inception to March 2009 for evidence pertaining to the safety and efficacy of selenium for lung cancers. Pubmed and EMBASE were searched to October 2009 for evidence on interactions with chemo- or radiation-therapy. In the efficacy analysis there were nine reports of five RCTs and two biomarker-based studies, 29 reports of 26 observational studies, and 41 preclinical studies. Fifteen human studies, one case report, and 36 preclinical studies were included in the interactions analysis. Based on available evidence, there appears to be a different chemopreventive effect dependent on baseline selenium status, such that selenium supplementation may reduce risk of lung cancers in populations with lower baseline selenium status (serumselenium (≥121.6 ng/mL). Pooling data from two trials yielded no impact to odds of lung cancer, OR 0.93 (95% confidence interval 0.61–1.43); other cancers that were the primary endpoints of these trials, OR 1.51 (95%CI 0.70–3.24); and all-cause-death, OR 0.93 (95%CI 0.79–1.10). In the treatment of lung cancers, selenium may reduce cisplatin-induced nephrotoxicity and side effects associated with radiation therapy. Conclusions Selenium may be effective for lung cancer prevention among individuals with lower selenium status, but at present should not be used as a general strategy for lung cancer prevention. Although promising, more evidence on the ability of selenium to reduce cisplatin and radiation therapy toxicity is required to ensure that therapeutic efficacy is maintained before any broad clinical recommendations can be made in this context. PMID:22073154

Pomegranate Extracts and Cancer Prevention: Molecular and Cellular Activities

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Syed, Deeba N.; Chamcheu, Jean-Christopher; Adhami, Vaqar M.; Mukhtar, Hasan

2014-01-01

There is increased appreciation by the scientific community that dietary phytochemicals can be potential weapons in the fight against cancer. Emerging data has provided new insights into the molecular and cellular framework needed to establish novel mechanism-based strategies for cancer prevention by selective bioactive food components. The unique chemical composition of the pomegranate fruit, rich in antioxidant tannins and flavonoids has drawn the attention of many investigators. Polyphenol rich fractions derived from the pomegranate fruit have been studied for their potential chemopreventive and/or cancer therapeutic effects in several animal models. Although data from in vitro and in vivo studies look convincing, well designed clinical trials in humans are needed to ascertain whether pomegranate can become part of our armamentarium against cancer. This review summarizes the available literature on the effects of pomegranate against various cancers. PMID:23094914

Colorectal Cancer Chemoprevention by Mesalazine and Its Derivatives

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Carmine Stolfi

2012-01-01

Full Text Available Patients with inflammatory bowel disease (IBD face an increased lifetime risk of developing colorectal cancer (CRC. Independent factors associated with increased risk include long disease duration, extensive colonic involvement, young age at onset of IBD, severity of inflammation, primary sclerosing cholangitis, backwash ileitis, and a family history of CRC, thus emphasising the role of intestinal inflammation as an underlying mechanism. This notion is also supported by the demonstration that the use of certain drugs used to attenuate the ongoing mucosal inflammation, such as mesalazine, seems to associate with a reduced incidence of colitis-associated CRC. In the last decade, work from many laboratories has contributed to delineate the mechanisms by which mesalazine alters CRC cell behaviour. In this paper, we review the available experimental data supporting the ability of mesalazine and its derivatives to interfere with intracellular signals involved in CRC cell growth.

Polymorphisms of xenobiotic metabolizing enzymes in bladder cancer patients of the Semmelweis University Budapest, Hungary.

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Ebbinghaus, Dörte; Bánfi, Gergely; Selinski, Silvia; Blaszkewicz, Meinolf; Bürger, Hannah; Hengstler, Jan G; Nyirády, Péter; Golka, Klaus

2017-01-01

Polymorphic xenobiotic metabolizing enzymes such as N-acetyltransferase 2 (NAT2) or glutathione S-transferase M1 (GSTM1) are known to modulate bladder cancer risk. As no apparent data were available from Hungary, a former member of the eastern European economic organization, a study was performed in Budapest. In total, 182 bladder cancer cases and 78 cancer-free controls were investigated by questionnaire. Genotypes of NAT2, GSTM1, GSTT1, rs1058396 and rs17674580 were determined by standard methods. Current smokers' crude odds ratio (OR) (3.43) and former smokers crude OR (2.36) displayed a significantly increased bladder cancer risk. The risk rose by a factor of 1.56 per 10 pack years. Exposure to fumes was associated with an elevated bladder cancer risk (23% cases, 13% controls). Sixty-four % of the cases and 59% of controls were slow NAT2 acetylators. It was not possible to establish a particular impact of NAT2*6A and *7B genotypes (15 cases, 8%, 5 controls, 7%). GSTT1 exerted no marked influence on bladder cancer (negative 21% cases vs. 22% controls). The portion of GSTM1 negative bladder cancer patients was increased (63% cases vs. 54% controls). The SLC14A1 SNPs rs1058396[AG/GG] and the nearby rs17674580[CT/TT] occurred more frequently in cases (79% and 68%) than controls (77% and 55%). The portion of GSTM1 negative bladder cancer patients is comparable with portions reported from other industrialized areas like Lutherstadt Wittenberg/Germany (58%), Dortmund/Germany (70%), Brescia/Italy (66%) or an occupational case-control series in Germany (56%). Data indicate that GSTM1 is a susceptibility factor for environmentally triggered bladder cancer rather than for smoking-mediated bladder cancer.

Imminent angiotensin-converting enzyme inhibitor from microbial source for cancer therapy

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Lida Ebrahimi

2017-01-01

Full Text Available Background: Drugs targeting Angiotensin I-converting enzyme (ACE have been used broadly in cancer chemotherapy. The recent past coupled with our results demonstrates the effective use of ACE inhibitors (ACEi as anticancer agents, and they are potentially relevant in deriving new inhibitors. Methods: Bacterial strains were isolated from cow milk collected in Coimbatore, Tamil Nadu, India and plated on nutrient agar medium. The identity of the strain was ascertained by 16s rRNA gene sequencing method and was submitted to the NCBI GenBank nucleotide database. Various substrates were screened for ACEi production by the fermentation with the isolated strain. ACEi was purified by sequential steps of ethanol precipitation, ion exchange column chromatography and gel filtration column chromatography. The apparent molecular mass was determined by SDS-PAGE. The anticancer property was analyzed by studying the cytotoxicity effects of ACEi using Breast cancer MCF-7 cell lines Results: The isolate coded as BUCTL09 was selected and identified as Micrococcus luteus. Among the seven substrates, only beef extract fermented broth showed an inhibition of 79% and was reported as the best substrate. The peptide was purified and molecular mass was determined. The IC50 value of peptide was found to be 59.5 μg/ ml. The purified peptide has demonstrated to induce apoptosis of cancer cell.Conclusions: The results of this study revealed that Peptide has been determined as an active compound that inhibited the activity of ACE. These properties indicate the possibilities of the use of purified protein as a potent anticancer agent.

Chemoprevention of Basal and Squamous Cell Carcinoma With a Single Course of Fluorouracil, 5%, Cream: A Randomized Clinical Trial.

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Weinstock, Martin A; Thwin, Soe Soe; Siegel, Julia A; Marcolivio, Kimberly; Means, Alexander D; Leader, Nicholas F; Shaw, Fiona M; Hogan, Daniel; Eilers, David; Swetter, Susan M; Chen, Suephy C; Jacob, Sharon E; Warshaw, Erin M; Stricklin, George P; Dellavalle, Robert P; Sidhu-Malik, Navjeet; Konnikov, Nellie; Werth, Victoria P; Keri, Jonette E; Robinson-Bostom, Leslie; Ringer, Robert J; Lew, Robert A; Ferguson, Ryan; DiGiovanna, John J; Huang, Grant D

2018-02-01

Keratinocyte carcinoma (ie, cutaneous basal and squamous cell carcinoma) is the most common cancer in the United States. To determine whether topical fluorouracil could prevent surgically treated keratinocyte carcinoma. The Veterans Affairs Keratinocyte Carcinoma Chemoprevention Trial was a randomized, double-blind, placebo-controlled trial of topical fluorouracil for chemoprevention of keratinocyte carcinoma. Participants were recruited from May 2009 to September 2011 from 12 Veterans Affairs medical centers and followed until June 30, 2013. Participants were veterans (n = 932) with a history of at least 2 keratinocyte carcinomas in the past 5 years; almost all were white males and the median age was 70 years. Application of fluorouracil, 5%, (n = 468) or vehicle control cream (n = 464) to the face and ears twice daily for 2 to 4 weeks upon randomization. Surgically treated keratinocyte, basal cell, and squamous cell carcinoma risk on the face and ears in the first year after enrollment; and time to first surgically treated keratinocyte, basal cell, and squamous cell carcinoma. The a priori hypothesis was that fluorouracil would be effective in preventing these cancers. Of 932 participants (916 men [98%]; 926 white [99%]; median age, 70 years), 299 developed a basal cell carcinoma end point (95 in year 1) and 108 developed a squamous cell carcinoma end point (25 in year 1) over 4 years (median follow-up, 2.8 years). Over the entire study, there was no difference between treatment groups in time to first keratinocyte, basal cell, or squamous cell carcinoma. During the first year, however, 5 participants (1%) in the fluorouracil group developed a squamous cell carcinoma vs 20 (4%) in the control group, a 75% (95% CI, 35%-91%) risk reduction (P = .002). The 11% reduction in basal cell carcinoma risk during year 1 (45 [10%] in the fluorouracil group vs 50 [11%] in the control group) was not statistically significant (95% CI, 39% reduction to 31

The chemopreventive potential of Curcuma purpurascens rhizome in reducing azoxymethane-induced aberrant crypt foci in rats

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Rouhollahi, Elham; Moghadamtousi, Soheil Zorofchian; Al-Henhena, Nawal; Kunasegaran, Thubasni; Hasanpourghadi, Mohadeseh; Looi, Chung Yeng; Abd Malek, Sri Nurestri; Awang, Khalijah; Abdulla, Mahmood Ameen; Mohamed, Zahurin

2015-01-01

Curcuma purpurascens BI. rhizome, a member of the Zingiberaceae family, is a popular spice in Indonesia that is traditionally used in assorted remedies. Dichloromethane extract of C. purpurascens BI. rhizome (DECPR) has previously been shown to have an apoptosis-inducing effect on colon cancer cells. In the present study, we examined the potential of DECPR to prevent colon cancer development in rats treated with azoxymethane (AOM) (15 mg/kg) by determining the percentage inhibition in incidence of aberrant crypt foci (ACF). Starting from the day immediately after AOM treatment, three groups of rats were orally administered once a day for 2 months either 10% Tween 20 (5 mL/kg, cancer control), DECPR (250 mg/kg, low dose), or DECPR (500 mg/kg, high dose). Meanwhile, the control group was intraperitoneally injected with 5-fluorouracil (35 mg/kg) for 5 consecutive days. After euthanizing the rats, the number of ACF was enumerated in colon tissues. Bax, Bcl-2, and proliferating cell nuclear antigen (PCNA) protein expressions were examined using immunohistochemical and Western blot analyses. Antioxidant enzymatic activity was measured in colon tissue homogenates and associated with malondialdehyde level. The percentage inhibition of ACF was 56.04% and 68.68% in the low- and high-dose DECPR-treated groups, respectively. The ACF inhibition in the treatment control group was 74.17%. Results revealed that DECPR exposure at both doses significantly decreased AOM-induced ACF formation, which was accompanied by reduced expression of PCNA. Upregulation of Bax and downregulation of Bcl-2 suggested the involvement of apoptosis in the chemopreventive effect of DECPR. In addition, the oxidative stress resulting from AOM treatment was significantly attenuated after administration of DECPR, which was shown by the elevated antioxidant enzymatic activity and reduced malondialdehyde level. Taken together, the present data clearly indicate that DECPR significantly inhibits ACF formation

OTUB1 de-ubiquitinating enzyme promotes prostate cancer cell invasion in vitro and tumorigenesis in vivo

DEFF Research Database (Denmark)

Iglesias-Gato, Diego; Chuan, Yin-Choy; Jiang, Ning

2015-01-01

BackgroundUbiquitination is a highly dynamic and reversible process with a central role in cell homeostasis. Deregulation of several deubiquitinating enzymes has been linked to tumor development but their specific role in prostate cancer progression remains unexplored.MethodsRNAi screening was us...

Positive regulation of prostate cancer cell growth by lipid droplet forming and processing enzymes DGAT1 and ABHD5.

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Mitra, Ranjana; Le, Thuc T; Gorjala, Priyatham; Goodman, Oscar B

2017-09-06

Neoplastic cells proliferate rapidly and obtain requisite building blocks by reprogramming metabolic pathways that favor growth. Previously, we observed that prostate cancer cells uptake and store lipids in the form of lipid droplets, providing building blocks for membrane synthesis, to facilitate proliferation and growth. Mechanisms of lipid uptake, lipid droplet dynamics and their contribution to cancer growth have yet to be defined. This work is focused on elucidating the prostate cancer-specific modifications in lipid storage pathways so that these modified gene products can be identified and therapeutically targeted. To identify genes that promote lipid droplet formation and storage, the expression profiles of candidate genes were assessed and compared between peripheral blood mononuclear cells and prostate cancer cells. Subsequently, differentially expressed genes were inhibited and growth assays performed to elucidate their role in the growth of the cancer cells. Cell cycle, apoptosis and autophagy assays were performed to ascertain the mechanism of growth inhibition. Our results indicate that DGAT1, ABHD5, ACAT1 and ATGL are overexpressed in prostate cancer cells compared to PBMCs and of these overexpressed genes, DGAT1 and ABHD5 aid in the growth of the prostate cancer cells. Blocking the expression of both DGAT1 and ABHD5 results in inhibition of growth, cell cycle block and cell death. DGAT1 siRNA treatment inhibits lipid droplet formation and leads to autophagy where as ABHD5 siRNA treatment promotes accumulation of lipid droplets and leads to apoptosis. Both the siRNA treatments reduce AMPK phosphorylation, a key regulator of lipid metabolism. While DGAT1 siRNA reduces phosphorylation of ACC, the rate limiting enzyme in de novo fat synthesis and triggers phosphorylation of raptor and ULK-1 inducing autophagy and cell death, ABHD5 siRNA decreases P70S6 phosphorylation, leading to PARP cleavage, apoptosis and cell death. Interestingly, DGAT-1 is involved

Polymorphisms in xenobiotic metabolizing enzymes and diet influence colorectal adenoma risk.

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Northwood, Emma L; Elliott, Faye; Forman, David; Barrett, Jennifer H; Wilkie, Murray J V; Carey, Francis A; Steele, Robert J C; Wolf, Roland; Bishop, Timothy; Smith, Gillian

2010-05-01

We have earlier shown that diet and xenobiotic metabolizing enzyme genotypes influence colorectal cancer risk, and now investigate whether similar associations are seen in patients with premalignant colorectal adenomas (CRA), recruited during the pilot phase of the Scottish Bowel Screening Programme. Nineteen polymorphisms in 13 genes [cytochrome P450 (P450), glutathione S-transferase (GST), N-acetyl transferase, quinone reductase (NQ01) and microsomal epoxide hydrolase (EPHX1) genes] were genotyped using multiplex PCR or Taqman-based allelic discrimination assays and analyzed in conjunction with diet, assessed by food frequency questionnaire, in a case-control study [317 CRA cases (308 cases genotyped), 296 controls]. Findings significant at a nominal 5% level are reported. CRA risk was inversely associated with fruit (P=0.02, test for trend) and vegetable (P=0.001, test for trend) consumption. P450 CYP2C9*3 heterozygotes had reduced CRA risk compared with homozygotes for the reference allele [odds ratio (OR): 0.60; 95% confidence interval (CI): 0.36-0.99], whereas CYP2D6*4 homozygotes (OR: 2.72; 95% CI: 1.18-6.27) and GSTM1 'null' individuals (OR: 1.43; 95% CI: 1.04-1.98) were at increased risk. The protective effect of fruit consumption was confined to GSTP1 (Ala114Val) reference allele homozygotes (OR: 0.49; 95% CI: 0.34-0.71, P=0.03 for interaction). CRA risk was not associated with meat consumption, although a significant interaction between red meat consumption and EPHX1 (His139Arg) genotype was noted (P=0.02 for interaction). We report the novel associations between P450 genotype and CRA risk, and highlight the risk association with GSTM1 genotype, common to our CRA and cancer case-control series. In addition, we report a novel modifying influence of GSTP1 genotype on dietary chemoprevention. These novel findings require independent confirmation.

DuCLOX-2/5 Inhibition Attenuates Inflammatory Response and Induces Mitochondrial Apoptosis for Mammary Gland Chemoprevention

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Swetlana Gautam

2018-04-01

Full Text Available The present study is a pursuit to define implications of dual cyclooxygenase-2 (COX-2 and 5-lipoxygenase (5-LOX (DuCLOX-2/5 inhibition on various aspects of cancer augmentation and chemoprevention. The monotherapy and combination therapy of zaltoprofen (COX-2 inhibitor and zileuton (5-LOX inhibitor were validated for their effect against methyl nitrosourea (MNU induced mammary gland carcinoma in albino wistar rats. The combination therapy demarcated significant effect upon the cellular proliferation as evidenced through decreased in alveolar bud count and restoration of the histopathological architecture when compared to toxic control. DuCLOX-2/5 inhibition also upregulated levels of caspase-3 and caspase-8, and restored oxidative stress markers (GSH, TBARs, protein carbonyl, SOD and catalase. The immunoblotting and qRT-PCR studies revealed the participation of the mitochondrial mediated death apoptosis pathway along with favorable regulation of COX-2, 5-LOX. Aforementioned combination restored the metabolic changes to normal when scrutinized through 1H NMR studies. Henceforth, the DuCLOX-2/5 inhibition was recorded to import significant anticancer effects in comparison to either of the individual treatments.

Prevention of Gastric Cancer: Eradication of Helicobacter Pylori and Beyond

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Tetsuya Tsukamoto

2017-08-01

Full Text Available Although its prevalence is declining, gastric cancer remains a significant public health issue. The bacterium Helicobacter pylori is known to colonize the human stomach and induce chronic atrophic gastritis, intestinal metaplasia, and gastric cancer. Results using a Mongolian gerbil model revealed that H. pylori infection increased the incidence of carcinogen-induced adenocarcinoma, whereas curative treatment of H. pylori significantly lowered cancer incidence. Furthermore, some epidemiological studies have shown that eradication of H. pylori reduces the development of metachronous cancer in humans. However, other reports have warned that human cases of atrophic metaplastic gastritis are already at risk for gastric cancer development, even after eradication of these bacteria. In this article, we discuss the effectiveness of H. pylori eradication and the morphological changes that occur in gastric dysplasia/cancer lesions. We further assess the control of gastric cancer using various chemopreventive agents.

Hydrogen sulfide-releasing naproxen suppresses colon cancer cell growth and inhibits NF-κB signaling

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Kodela R

2015-08-01

Full Text Available Ravinder Kodela,1 Niharika Nath,2 Mitali Chattopadhyay,1 Diandra E Nesbitt,1 Carlos A Velázquez-Martínez,3 Khosrow Kashfi11Department of Physiology, Pharmacology and Neuroscience, Sophie Davis School of Biomedical Education, City University of New York Medical School, 2Department of Life Sciences, New York Institute of Technology, New York, NY, USA; 3Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada Abstract: Colorectal cancer (CRC is the second leading cause of death due to cancer and the third most common cancer in men and women in the USA. Nuclear factor kappa B (NF-κB is known to be activated in CRC and is strongly implicated in its development and progression. Therefore, activated NF-κB constitutes a bona fide target for drug development in this type of malignancy. Many epidemiological and interventional studies have established nonsteroidal anti-inflammatory drugs (NSAIDs as a viable chemopreventive strategy against CRC. Our previous studies have shown that several novel hydrogen sulfide-releasing NSAIDs are promising anticancer agents and are safer derivatives of NSAIDs. In this study, we examined the growth inhibitory effect of a novel H2S-releasing naproxen (HS-NAP, which has a repertoire as a cardiovascular-safe NSAID, for its effects on cell proliferation, cell cycle phase transitions, and apoptosis using HT-29 human colon cancer cells. We also investigated its effect as a chemopreventive agent in a xenograft mouse model. HS-NAP suppressed the growth of HT-29 cells by induction of G0/G1 arrest and apoptosis and downregulated NF-κB. Tumor xenografts in mice were significantly reduced in volume. The decrease in tumor mass was associated with a reduction of cell proliferation, induction of apoptosis, and decreases in NF-κB levels in vivo. Therefore, HS-NAP demonstrates strong anticancer potential in CRC. Keywords: nonsteroidal anti-inflammatory drugs, cell cycle, apoptosis, xenograft, NF

Acyclic retinoid in chemoprevention of hepatocellular carcinoma: Targeting phosphorylated retinoid X receptor-α for prevention of liver carcinogenesis

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Masahito Shimizu

2012-01-01

Full Text Available One of the key features of hepatocellular carcinoma (HCC is the high rate of intrahepatic recurrence that correlates with poor prognosis. Therefore, in order to improve the clinical outcome for patients with HCC, development of a chemopreventive agent that can decrease or delay the incidence of recurrence is a critical issue for urgent investigation. Acyclic retinoid (ACR, a synthetic retinoid, successfully improves HCC patient survival by preventing recurrence and the formation of secondary tumors. A malfunction of the retinoid X receptor-α (RXRα due to phosphorylation by the Ras-MAPK signaling pathway plays a critical role in liver carcinogenesis, and ACR exerts chemopreventive effects on HCC development by inhibiting RXRα phosphorylation. Here, we review the relationship between retinoid signaling abnormalities and liver disease, the mechanisms of how RXRα phosphorylation contributes to liver carcinogenesis, and the detailed effects of ACR on preventing HCC development, especially based on the results of our basic and clinical research. We also outline the concept of "clonal deletion and inhibition" therapy, which is defined as the removal and inhibition of latent malignant clones from the liver before they expand into clinically detectable HCC, because ACR prevents the development of HCC by implementing this concept. Looking toward the future, we discuss "combination chemoprevention" using ACR as a key drug since it can generate a synergistic effect, and may thus be an effective new strategy for the prevention of HCC.

Nutrients, foods, and colorectal cancer prevention.

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Song, Mingyang; Garrett, Wendy S; Chan, Andrew T

2015-05-01

Diet has an important role in the development of colorectal cancer. In the past few decades, findings from extensive epidemiologic and experimental investigations have linked consumption of several foods and nutrients to the risk of colorectal neoplasia. Calcium, fiber, milk, and whole grains have been associated with a lower risk of colorectal cancer, and red meat and processed meat have been associated with an increased risk. There is substantial evidence for the potential chemopreventive effects of vitamin D, folate, fruits, and vegetables. Nutrients and foods also may interact, as a dietary pattern, to influence colorectal cancer risk. Diet likely influences colorectal carcinogenesis through several interacting mechanisms. These include the direct effects on immune responsiveness and inflammation, and the indirect effects of overnutrition and obesity-risk factors for colorectal cancer. Emerging evidence also implicates the gut microbiota as an important effector in the relationship between diet and cancer. Dietary modification therefore has the promise of reducing colorectal cancer incidence. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.

Polyphenols from the Mediterranean herb rosemary (Rosmarinus officinalis for prostate cancer

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Sakina M Petiwala

2013-03-01

Full Text Available The Mediterranean diet is rich in fruits and vegetables and has been associated with a variety of health benefits including cancer prevention. One aspect of the diet that has not received enough attention is Mediterranean herbs. Specifically, rosemary and its polyphenolic diterpenes (carnosic acid and carnosol are known to possess antioxidant activity that may be beneficial for cancer control. Herein, we describe the in vitro and in vivo studies carried out towards understanding the molecular mechanisms of carnosic acid and carnosol leading to inhibition of prostate cancer. The reported findings suggest that these polyphenols target multiple signaling pathways involved in cell cycle modulation and apoptosis. Further work is required to understand its potential for health promotion and potential drug discovery for prostate cancer chemoprevention.

Matrix Metalloproteinase Enzyme Family

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Ozlem Goruroglu Ozturk

2013-04-01

Full Text Available Matrix metalloproteinases play an important role in many biological processes such as embriogenesis, tissue remodeling, wound healing, and angiogenesis, and in some pathological conditions such as atherosclerosis, arthritis and cancer. Currently, 24 genes have been identified in humans that encode different groups of matrix metalloproteinase enzymes. This review discuss the members of the matrix metalloproteinase family and their substrate specificity, structure, function and the regulation of their enzyme activity by tissue inhibitors. [Archives Medical Review Journal 2013; 22(2.000: 209-220

Histone acetyltransferases : challenges in targeting bi-substrate enzymes

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Wapenaar, Hannah; Dekker, Frank J

2016-01-01

Histone acetyltransferases (HATs) are epigenetic enzymes that install acetyl groups onto lysine residues of cellular proteins such as histones, transcription factors, nuclear receptors, and enzymes. HATs have been shown to play a role in diseases ranging from cancer and inflammatory diseases to

The ErbB family and androgen receptor signaling are targets of Celecoxib in prostate cancer.

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Brizzolara, Antonella; Benelli, Roberto; Venè, Roberta; Barboro, Paola; Poggi, Alessandro; Tosetti, Francesca; Ferrari, Nicoletta

2017-08-01

Inflammation plays a central role in prostate cancer (PCa) development through significant crosstalk between the COX-2-ErbB family receptor network and androgen receptor (AR)-EGFR signaling pathways. The purpose of this work was to determine the ability of the COX-2 inhibitor Celecoxib to modulate the EGFR-AR signaling pathway in androgen-dependent PCa cells and to provide a rationale for its beneficial use in chemopreventive strategies. Functional studies of Celecoxib activity were performed on LNCaP prostate cancer cells. Western blotting, gene expression analysis, dual-luciferase reporter assay and ELISA were applied to assess the Celecoxib mechanisms of action. We found that Celecoxib, through EGF and amphiregulin (AREG) induction, caused EGFR and ErbB2 activation and consequent degradation associated with the inhibition of androgenic signaling. By upregulating the E3 ubiquitin ligase Nrdp1, Celecoxib also efficiently downregulated ErbB3, which is strongly implicated in castration-resistant prostate cancer. Lastly, Celecoxib directly regulated AR transcription and translation independent of ErbB activation by downregulating the RNA binding protein heterogeneous nuclear ribonucleoprotein K (hnRNP K). The simultaneous suppression of ErbB kinases and androgen signaling by Celecoxib represents a novel strategy to interrupt the vicious cycle of AR/ErbB cross-talk with the primary purpose of undermining their resilient signaling in prostate cancer progression. Our data provide important premises for the chemopreventive use of Celecoxib in the clinical management of prostate cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterization of SV-40 Tag rats as a model to study prostate cancer

International Nuclear Information System (INIS)

Harper, Curt E; Patel, Brijesh B; Cook, Leah M; Wang, Jun; Shirai, Tomoyuki; Eltoum, Isam A; Lamartiniere, Coral A

2009-01-01

Prostate cancer is the second most frequently diagnosed cancer in men. Animal models that closely mimic clinical disease in humans are invaluable tools in the fight against prostate cancer. Recently, a Simian Virus-40 T-antigen (SV-40 Tag) targeted probasin promoter rat model was developed. This model, however, has not been extensively characterized; hence we have investigated the ontogeny of prostate cancer and determined the role of sex steroid receptor and insulin-like growth factor-1 (IGF-1) signaling proteins in the novel SV-40 Tag rat. The SV-40 Tag rat was histopathologically characterized for time to tumor development, incidence and multiplicity and in the ventral, dorsal, lateral and anterior lobes of the prostate. Immunoassay techniques were employed to measure cell proliferation, apoptosis, and sex steroid receptor and growth factor signaling-related proteins. Steroid hormone concentrations were measured via coated well enzyme linked immunosorbent assay (ELISA) kits. Prostatic intraepithelial neoplasia (PIN) and well-differentiated prostate cancer developed as early as 2 and 10 weeks of age, respectively in the ventral prostate (VP) followed by in the dorsolateral (DLP). At 8 weeks of age, testosterone and dihydrotestosterone (DHT) concentrations in SV-40 Tag rats were increased when compared to non-transgenic rats. High cell proliferation and apoptotic indices were found in VP and DLP of transgenic rats. Furthermore, we observed increased protein expression of androgen receptor, IGF-1, IGF-1 receptor, and extracellular signal-regulated kinases in the prostates of SV-40 Tag rats. The rapid development of PIN and prostate cancer in conjunction with the large prostate size makes the SV-40 Tag rat a useful model for studying prostate cancer. This study provides evidence of the role of sex steroid and growth factor proteins in prostate cancer development and defines appropriate windows of opportunity for preclinical trials and aids in the rational design of

Pharmacokinetics of dietary cancer chemopreventive compound dibenzoylmethane in rats and the impact of nanoemulsion and genetic knockout of Nrf2 on its disposition.

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Lin, Wen; Hong, Jin-Liern; Shen, Guoxiang; Wu, Rachel T; Wang, Yuwen; Huang, Mou-Tuan; Newmark, Harold L; Huang, Qingrong; Khor, Tin Oo; Heimbach, Tycho; Kong, Ah-Ng

2011-03-01

The pharmacokinetic disposition of a dietary cancer chemopreventive compound dibenzoylmethane (DBM) was studied in male Sprague-Dawley rats after intravenous (i.v.) and oral (p.o.) administrations. Following a single i.v. bolus dose, the mean plasma clearance (CL) of DBM was low compared with the hepatic blood flow. DBM displayed a high volume of distribution (Vss). The elimination terminal t1/2 was long. The mean CL, Vss and AUC0-∞/dose were similar between the i.v. 10 and 10 mg/kg doses. After single oral doses (10, 50 and 250 mg/kg), the absolute oral bioavailability (F*) of DBM was 7.4%-13.6%. The increase in AUC was not proportional to the oral doses, suggesting non-linearity. In silico prediction of oral absorption also demonstrated low DBM absorption in vivo. An oil-in-water nanoemulsion containing DBM was formulated to potentially overcome the low F* due to poor water solubility of DBM, with enhanced oral absorption. Finally, to examine the role of Nrf2 on the pharmacokinetics of DBM, since DBM activates the Nrf2-dependent detoxification pathways, Nrf2 wild-type (+/+) mice and Nrf2 knockout (-/-) mice were utilized. There was an increased systemic plasma exposure of DBM in Nrf2 (-/-) mice, suggesting that the Nrf2 genotype could also play a role in the pharmacokinetic disposition of DBM. Taken together, the results show that DBM has low oral bioavailability which could be due in part to poor water solubility and this could be overcome by a nanotechnology-based drug delivery system and furthermore the Nrf2 genotype could also play a role in the pharmacokinetics of DBM. Copyright © 2010 John Wiley & Sons, Ltd.

Inhibition of Sphingolipid Metabolism Enhances Resveratrol Chemotherapy in Human Gastric Cancer Cells

OpenAIRE

Shin, Kyong-Oh; Park, Nam-Young; Seo, Cho-Hee; Hong, Seon-Pyo; Oh, Ki-Wan; Hong, Jin-Tae; Han, Sang-Kil; Lee, Yong-Moon

2012-01-01

Resveratrol, a chemopreventive agent, is rapidly metabolized in the intestine and liver via glucuronidation. Thus, the pharmacokinetics of resveratrol limits its efficacy. To improve efficacy, the activity of resveratrol was investigated in the context of sphingolipid metabolism in human gastric cancer cells. Diverse sphingolipid metabolites, including dihydroceramides (DHCer), were tested for their ability to induce resveratrol cytotoxicity. Exposure to resveratrol (100 ?M) for 24 hr induced...

Phenolic extract from oleaster (Olea europaea var. Sylvestris) leaves reduces colon cancer growth and induces caspase-dependent apoptosis in colon cancer cells via the mitochondrial apoptotic pathway.

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Zeriouh, Wafa; Nani, Abdelhafid; Belarbi, Meriem; Dumont, Adélie; de Rosny, Charlotte; Aboura, Ikram; Ghanemi, Fatima Zahra; Murtaza, Babar; Patoli, Danish; Thomas, Charles; Apetoh, Lionel; Rébé, Cédric; Delmas, Dominique; Khan, Naim Akhtar; Ghiringhelli, François; Rialland, Mickael; Hichami, Aziz

2017-01-01

Dietary polyphenols, derived from natural products, have received a great interest for their chemopreventive properties against cancer. In this study, we investigated the effects of phenolic extract of the oleaster leaves (PEOL) on tumor growth in mouse model and on cell death in colon cancer cell lines. We assessed the effect of oleaster leaf infusion on HCT116 (human colon cancer cell line) xenograft growth in athymic nude mice. We observed that oleaster leaf polyphenol-rich infusion limited HCT116 tumor growth in vivo. Investigations of PEOL on two human CRC cell lines showed that PEOL induced apoptosis in HCT116 and HCT8 cells. We demonstrated an activation of caspase-3, -7 and -9 by PEOL and that pre-treatment with the pan-caspase inhibitor, N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk), prevented PEOL-induced cell death. We observed an involvement of the mitochondrial pathway in PEOL-induced apoptosis evidenced by reactive oxygen species (ROS) production, a decrease of mitochondrial membrane potential, and cytochrome c release. Increase in intracellular Ca2+ concentration induced by PEOL represents the early event involved in mitochondrial dysfunction, ROS-induced endoplasmic reticulum (ER) stress and apoptosis induced by PEOL, as ruthenium red, an inhibitor of mitochondrial calcium uptake inhibited apoptotic effect of PEOL, BAPTA/AM inhibited PEOL-induced ROS generation and finally, N-acetyl-L-cysteine reversed ER stress and apoptotic effect of PEOL. These results demonstrate that polyphenols from oleaster leaves might have a strong potential as chemopreventive agent in colorectal cancer.

Roles of Dietary Phytoestrogens on the Regulation of Epithelial-Mesenchymal Transition in Diverse Cancer Metastasis

Science.gov (United States)

Lee, Geum-A.; Hwang, Kyung-A.; Choi, Kyung-Chul

2016-01-01

Epithelial-mesenchymal transition (EMT) plays a key role in tumor progression. The cells undergoing EMT upregulate the expression of cell motility-related proteins and show enhanced migration and invasion. The hallmarks of EMT in cancer cells include changed cell morphology and increased metastatic capabilities in cell migration and invasion. Therefore, prevention of EMT is an important tool for the inhibition of tumor metastasis. A novel preventive therapy is needed, such as treatment of natural dietary substances that are nontoxic to normal human cells, but effective in inhibiting cancer cells. Phytoestrogens, such as genistein, resveratrol, kaempferol and 3,3′-diindolylmethane (DIM), can be raised as possible candidates. They are plant-derived dietary estrogens, which are found in tea, vegetables and fruits, and are known to have various biological efficacies, including chemopreventive activity against cancers. Specifically, these phytoestrogens may induce not only anti-proliferation, apoptosis and cell cycle arrest, but also anti-metastasis by inhibiting the EMT process in various cancer cells. There have been several signaling pathways found to be associated with the induction of the EMT process in cancer cells. Phytoestrogens were demonstrated to have chemopreventive effects on cancer metastasis by inhibiting EMT-associated pathways, such as Notch-1 and TGF-beta signaling. As a result, phytoestrogens can inhibit or reverse the EMT process by upregulating the expression of epithelial phenotypes, including E-cadherin, and downregulating the expression of mesenchymal phenotypes, including N-cadherin, Snail, Slug, and vimentin. In this review, we focused on the important roles of phytoestrogens in inhibiting EMT in many types of cancer and suggested phytoestrogens as prominent alternative compounds to chemotherapy. PMID:27231938

Review article: colitis-associated cancer -- time for new strategies.

LENUS (Irish Health Repository)

Shanahan, F

2012-02-03

Colorectal cancer (CRC) remains a feared and potentially life-threatening complication of both ulcerative colitis and Crohn\\'s colitis. Currently, the main preventive strategy is a secondary one, i.e. surveillance colonoscopy usually after 8 years of disease duration, when the risk for neoplasia begins to increase. Despite its widespread acceptance, dysplasia and cancer surveillance is unproven in terms of reducing mortality or morbidity and there is a remarkable lack of uniformity in the manner in which it is practised. In this review article, the pitfalls of dysplasia surveillance are summarized and the need for novel chemopreventive and perhaps pharmabiotic approaches for prevention are highlighted.

Encapsulated nanoepigallocatechin-3-gallate and elemental selenium nanoparticles as paradigms for nanochemoprevention

Directory of Open Access Journals (Sweden)

Wang D

2012-03-01

Full Text Available Dongxu Wang1, Ethan Will Taylor2, Yijun Wang1, Xiaochun Wan1, Jinsong Zhang11Key Laboratory of Tea Biochemistry and Biotechnology, School of Tea and Food Science, Anhui Agricultural University, Hefei, Anhui, People’s Republic of China; 2Department of Nanoscience, Joint School of Nanoscience and Nanoengineering, University of North Carolina at Greensboro, Greensboro, NC, USAAbstract: Chemoprevention that impedes one or more steps in carcinogenesis, via long-term administration of naturally occurring or synthetic compounds, is widely considered to be a crucial strategy for cancer control. Selenium (Se has chemopreventive effects, but its application is limited due to a low therapeutic index as shown in numerous animal experiments. In contrast to Se, which was known for its toxicity prior to the discovery of its beneficial effects, the natural compound epigallocatechin-3-gallate (EGCG was originally considered to be nontoxic. Due to its preventive effects on many types of cancer in various animal models, EGCG has been regarded as a prime example of a promising chemopreventive agent without major toxicity concerns. However, very recently, evidence has accumulated showing that efficacious doses of EGCG used in health promotion may not be far from its toxic dose level. Therefore, both Se and EGCG need to be modified by novel pharmaceutical technologies to attain enhanced efficacy and/or reduced toxicity. Nanotechnology may be one of these technologies. In support of this hypothesis, the characteristics of polylactic acid and polyethylene glycol-encapsulated nano-EGCG and elemental Se nanoparticles dispersed by bovine serum albumin are reviewed in this article. Encapsulation of EGCG to form nano-EGCG leads to its enhanced stability in plasma and remarkably superior chemopreventive effects, with more than tenfold dose advantages in inducing apoptosis and inhibition of both angiogenesis and tumor growth. Se at nanoparticle size (“Nano-Se”, compared

Health Promoting Effects of Brassica-Derived Phytochemicals: From Chemopreventive and Anti-Inflammatory Activities to Epigenetic Regulation

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Anika Eva Wagner

2013-01-01

Full Text Available A high intake of brassica vegetables may be associated with a decreased chronic disease risk. Health promoting effects of Brassicaceae have been partly attributed to glucosinolates and in particular to their hydrolyzation products including isothiocyanates. In vitro and in vivo studies suggest a chemopreventive activity of isothiocyanates through the redox-sensitive transcription factor Nrf2. Furthermore, studies in cultured cells, in laboratory rodents, and also in humans support an anti-inflammatory effect of brassica-derived phytochemicals. However, the underlying mechanisms of how these compounds mediate their health promoting effects are yet not fully understood. Recent findings suggest that brassica-derived compounds are regulators of epigenetic mechanisms. It has been shown that isothiocyanates may inhibit histone deacetylase transferases and DNA-methyltransferases in cultured cells. Only a few papers have dealt with the effect of brassica-derived compounds on epigenetic mechanisms in laboratory animals, whereas data in humans are currently lacking. The present review aims to summarize the current knowledge regarding the biological activities of brassica-derived phytochemicals regarding chemopreventive, anti-inflammatory, and epigenetic pathways.

Skp2 is a Promising Therapeutic Target in Breast Cancer

Energy Technology Data Exchange (ETDEWEB)

Wang, Zhiwei; Fukushima, Hidefumi; Inuzuka, Hiroyuki; Wan, Lixin; Liu, Pengda; Gao, Daming [Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (United States); Sarkar, Fazlul H. [Department of Pathology, Karmanos Cancer Institute, School of Medicine, Wayne State University, Detroit, MI (United States); Wei, Wenyi, E-mail: wwei2@bidmc.harvard.edu [Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA (United States)

2012-01-04

Breast cancer is the most common type of cancer among American women, and remains the second leading cause of cancer-related death for female in the United States. It has been known that several signaling pathways and various factors play critical roles in the development and progression of breast cancer, such as estrogen receptor, Notch, PTEN, human epidermal growth factor receptor 2, PI3K/Akt, BRCA1, and BRCA2. Emerging evidence has shown that the F-box protein S-phase kinase associated protein 2 (Skp2) also plays an important role in the pathogenesis of breast cancer. Therefore, in this brief review, we summarize the novel functions of Skp2 in the pathogenesis of breast cancer. Moreover, we provide further evidence regarding the state of our knowledge toward the development of novel Skp2 inhibitors especially natural “chemopreventive agents” as targeted approach for the prevention and/or treatment of breast cancer.

Sulforaphane modulates telomerase activity via epigenetic regulation in prostate cancer cell lines.

Science.gov (United States)

Abbas, Ata; Hall, J Adam; Patterson, William L; Ho, Emily; Hsu, Anna; Al-Mulla, Fahd; Georgel, Philippe T

2016-02-01

Epidemiologic studies have revealed that diets rich in sulforaphane (SFN), an isothiocyanate present in cruciferous vegetables, are associated with a marked decrease in prostate cancer incidence. The chemo-preventive role of SFN is associated with its histone de-acetylase inhibitor activity. However, the effect of SFN on chromatin composition and dynamic folding, especially in relation to HDAC inhibitor activity, remains poorly understood. In this study, we found that SFN can inhibit the expression and activity of human telomerase reverse transcriptase (hTERT), the catalytic subunit of telomerase, in 2 prostate cancer cell lines. This decrease in gene expression is correlated with SFN-induced changes in chromatin structure and composition. The SFN-mediated changes in levels of histone post-translational modifications, more specifically acetylation of histone H3 lysine 18 and di-methylation of histone H3 lysine 4, 2 modifications linked with high risk of prostate cancer recurrence, were associated with regulatory elements within the hTERT promoter region. Chromatin condensation may also play a role in SFN-mediated hTERT repression, since expression and recruitment of MeCP2, a known chromatin compactor, were altered in SFN treated prostate cancer cells. Chromatin immuno-precipitation (ChIP) of MeCP2 showed enrichment over regions of the hTERT promoter with increased nucleosome density. These combined results strongly support a role for SFN in the mediation of epigenetic events leading to the repression of hTERT in prostate cancer cells. This ability of SFN to modify chromatin composition and structure associated with target gene expression provides a new model by which dietary phytochemicals may exert their chemoprevention activity.

Kefir and Cancer: A Systematic Review of Literatures.

Science.gov (United States)

Rafie, Nahid; Golpour Hamedani, Sahar; Ghiasvand, Reza; Miraghajani, Maryam

2015-12-01

Some studies have suggested chemopreventive effects of kefir, a fermented milk product, on carcinogenesis. The aim of this review study was to evaluate the scientific evidence for effects of kefir on cancer prevention and treatment. We systematically searched for all relevant studies published before June 2015, using PubMed, Google scholar, Cochrane and Science Direct, SID, MedLib and Srlst databases. Relevant studies were reviewed based on systematic review (PRISMA) guidelines. From a total of 2208 papers obtained at the initial database search, 11 publications including 7 in vitro and 4 experimental studies were eligible. In vitro studies on breast, colon, skin and gastric cancers and leukemia cell lines and experimental studies on different sarcomas consistently showed beneficial effects of kefir on cancer prevention and treatment. The results of this systematic review suggest that kefir may be associated with cancer prevention and it also has beneficial effects in cancer treatment. This protection may be associated with kefir bioactive components including peptides, polysaccharides and sphingolipids.

Norcantharidin, Derivative of Cantharidin, for Cancer Stem Cells

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Chen-Hsi Hsieh

2013-01-01

Full Text Available Cancer stem cells (CSCs existing in human cancers have been demonstrated to be a major cause of cancer treatment resistance, invasion, metastasis, and relapse. Self-renewal pathways, Wnt/β-catenin, Sonic hedgehog (Shh, and the Notch signaling pathway play critical roles in developing CSCs and lead to angiogenesis, migration, invasion, and metastasis. Multidrug resistance (MDR is an unfavorable factor causing the failure of treatments against cancer cells. The most important and thoroughly studied mechanism involved in MDR is the active efflux of chemotherapeutic agents through membrane drug transporters. There is growing evidence that Norcantharidin (NCTD, a water-soluble synthetic small molecule derivative of naturally occurring cantharidin from the medicinal insect blister beetle (Mylabris phalerata Pallas, is capable of chemoprevention and tumor inhibition. We summarize investigations into the modulation of self-renewal pathways and MDR in CSCs by NCTD. This review may aid in further investigation of using NCTD to develop more effective strategies for cancer treatment to reduce resistance and recurrence.

Genetic polymorphisms in 5-Fluorouracil-related enzymes predict pathologic response after neoadjuvant chemoradiation for rectal cancer.

Science.gov (United States)

Nelson, Bailey; Carter, Jane V; Eichenberger, Maurice R; Netz, Uri; Galandiuk, Susan

2016-11-01

Many patients with rectal cancer undergo preoperative neoadjuvant chemoradiation, with approximately 70% exhibiting pathologic downstaging in response to treatment. Currently, there is no accurate test to predict patients who are likely to be complete responders to therapy. 5-Fluorouracil is used regularly in the neoadjuvant treatment of rectal cancer. Genetic polymorphisms affect the activity of thymidylate synthase, an enzyme involved in 5-Fluorouracil metabolism, which may account for observed differences in response to neoadjuvant treatment between patients. Detection of genetic polymorphisms might identify patients who are likely to have a complete response to neoadjuvant therapy and perhaps allow them to avoid operation. DNA was isolated from whole blood taken from patients with newly diagnosed rectal cancer who received neoadjuvant therapy (n = 50). Response to therapy was calculated with a tumor regression score based on histology from the time of operation. Polymerase chain reaction was performed targeting the promoter region of thymidylate synthase. Polymerase chain reaction products were separated using electrophoresis to determine whether patients were homozygous for a double-tandem repeat (2R), a triple-tandem repeat (3R), or were heterozygous (2R/3R). A single nucleotide polymorphism, 3G or 3C, also may be present in the second repeat unit of the triple-tandem repeat allele. Restriction fragment length polymorphism assays were performed in patients with at least one 3R allele using HaeIII. Patients with at least 1 thymidylate synthase 3G allele were more likely to have a complete or partial pathologic response to 5-Fluorouracil neoadjuvant therapy (odds ratio 10.4; 95% confidence interval, 1.3-81.6; P = .01) than those without at least one 3G allele. Identification of rectal cancer patients with specific genetic polymorphisms in enzymes involved in 5-Fluorouracil metabolism seems to predict the likelihood of complete or partial pathologic response

3,3'-Diindolylmethane downregulates pro-survival pathway in hormone independent prostate cancer

International Nuclear Information System (INIS)

Garikapaty, Venkata P.S.; Ashok, Badithe T.; Tadi, Kiranmayi; Mittelman, Abraham; Tiwari, Raj K.

2006-01-01

Epidemiological evidences suggest that the progression and promotion of prostate cancer (CaP) can be modulated by diet. Since all men die with prostate cancer rather than of the disease, it is of particular interest to prevent or delay the progression of the disease by chemopreventive strategies. We have been studying the anticancer properties of compounds present in cruciferous vegetables such as indole-3-carbinol (I3C). Diindolylmethane (DIM) is a dimer of I3C that is formed under acidic conditions and unlike I3C is more stable with higher anti-cancer effects. In the present report, we demonstrate that DIM is a potent anti-proliferative agent compared to I3C in the hormone independent DU 145 CaP cells. The anti-prostate cancer effect is mediated by the inhibition of the Akt signal transduction pathway as DIM, in sharp contrast to I3C, induces the downregulation of Akt, p-Akt, and PI3 kinase. DIM also induced a G1 arrest in DU 145 cells by flow cytometry and downstream concurrent inhibition of cell cycle parameters such as cyclin D1, cdk4, and cdk6. Our data suggest a need for further development of DIM, as a chemopreventive agent for CaP, which justifies epidemiological evidences and molecular targets that are determinants for CaP dissemination/progression. The ingestion of DIM may benefit CaP patients and reduce disease recurrence by eliminating micro-metastases that may be present in patients who undergo radical prostatectomy

Prevention of breast cancer.

Science.gov (United States)

Olver, Ian N

2016-11-21

Modifiable lifestyle factors may reduce the risk of developing breast cancer. Obesity is associated particularly with post-menopausal breast cancer. Diet is important, and exercise equivalent to running for up to 8 hours each week reduces the risk of breast cancer, both in its own right and through reducing obesity. Alcohol consumption may be responsible for 5.8% of breast cancers in Australia and it is recommended to reduce this to two standard drinks per day. Drinking alcohol and smoking increases the risk for breast cancer and, therefore, it is important to quit tobacco smoking. Prolonged use of combined oestrogen and progesterone hormone replacement therapy and oral contraceptives may increase breast cancer risk and this must be factored into individual decisions about their use. Ionising radiation, either from diagnostic or therapeutic radiation or through occupational exposure, is associated with a high incidence of breast cancer and exposure may be reduced in some cases. Tamoxifen chemoprevention may reduce the incidence of oestrogen receptor positive cancer in 51% of women with high risk of breast cancer. Uncommon but serious side effects include thromboembolism and uterine cancer. Raloxifene, which can also reduce osteoporosis, can be used in post-menopausal women and is not associated with the development of uterine cancer. Surgical prophylaxis with bilateral mastectomy and salpingo-oophorectomy can reduce the risk of breast cancer in patients carrying BRCA1 or BRCA2 mutations. For preventive treatments, mammographic screening can identify other women at high risk.

[Utility of chromosome banding with ALU I enzyme for identifying methylated areas in breast cancer].

Science.gov (United States)

Rojas-Atencio, Alicia; Yamarte, Leonard; Urdaneta, Karelis; Soto-Alvarez, Marisol; Alvarez Nava, Francisco; Cañizalez, Jenny; Quintero, Maribel; Atencio, Raquel; González, Richard

2012-12-01

Cancer is a group of disorders characterized by uncontrolled cell growth which is produced by two successive events: increased cell proliferation (tumor or neoplasia) and the invasive capacity of these cells (metastasis). DNA methylation is an epigenetic process which has been involved as an important pathogenic factor of cancer. DNA methylation participates in the regulation of gene expression, directly, by preventing the union of transcription factors, and indirectly, by promoting the "closed" structure of the chromatine. The objectives of this study were to identify hypermethyled chromosomal regions through the use of restriction Alu I endonuclease, and to relate cytogenetically these regions with tumor suppressive gene loci. Sixty peripheral blood samples of females with breast cancer were analyzed. Cell cultures were performed and cytogenetic spreads, previously digested with Alu I enzyme, were stained with Giemsa. Chromosomal centromeric and not centromeric regions were stained in 37% of cases. About 96% of stained hypermethyled chromosomal regions (1q, 2q, 6q) were linked with methylated genes associated with breast cancer. In addition, centromeric regions in chromosomes 3, 4, 8, 13, 14, 15 and 17, usually unstained, were found positive to digestion with Alu I enzime and Giemsa staining. We suggest the importance of this technique for the global visualization of the genome which can find methylated genes related to breast cancer, and thus lead to a specific therapy, and therefore a better therapeutic response.

Random-walk enzymes

Science.gov (United States)

Mak, Chi H.; Pham, Phuong; Afif, Samir A.; Goodman, Myron F.

2015-09-01

Enzymes that rely on random walk to search for substrate targets in a heterogeneously dispersed medium can leave behind complex spatial profiles of their catalyzed conversions. The catalytic signatures of these random-walk enzymes are the result of two coupled stochastic processes: scanning and catalysis. Here we develop analytical models to understand the conversion profiles produced by these enzymes, comparing an intrusive model, in which scanning and catalysis are tightly coupled, against a loosely coupled passive model. Diagrammatic theory and path-integral solutions of these models revealed clearly distinct predictions. Comparison to experimental data from catalyzed deaminations deposited on single-stranded DNA by the enzyme activation-induced deoxycytidine deaminase (AID) demonstrates that catalysis and diffusion are strongly intertwined, where the chemical conversions give rise to new stochastic trajectories that were absent if the substrate DNA was homogeneous. The C →U deamination profiles in both analytical predictions and experiments exhibit a strong contextual dependence, where the conversion rate of each target site is strongly contingent on the identities of other surrounding targets, with the intrusive model showing an excellent fit to the data. These methods can be applied to deduce sequence-dependent catalytic signatures of other DNA modification enzymes, with potential applications to cancer, gene regulation, and epigenetics.

Induction of human microsomal prostaglandin E synthase 1 by activated oncogene RhoA GTPase in A549 human epithelial cancer cells

Energy Technology Data Exchange (ETDEWEB)

Choi, Hye Jin [Laboratory of Systems Mucosal Biomodulation, Department of Microbiology and Immunology, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Lee, Dong-Hyung [Department of Obstetrics and Gynecology, Medical Research Institute, Pusan National University, Busan (Korea, Republic of); Park, Seong-Hwan; Kim, Juil; Do, Kee Hun [Laboratory of Systems Mucosal Biomodulation, Department of Microbiology and Immunology, Pusan National University School of Medicine, Yangsan (Korea, Republic of); An, Tae Jin; Ahn, Young Sup; Park, Chung Berm [Department of Herbal Crop Research, NIHHS, RDA, Eumseong (Korea, Republic of); Moon, Yuseok, E-mail: moon@pnu.edu [Laboratory of Systems Mucosal Biomodulation, Department of Microbiology and Immunology, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Medical Research Institute and Research Institute for Basic Sciences, Pusan National University, Busan (Korea, Republic of)

2011-09-30

Highlights: {yields} As a target of oncogene RhoA-linked signal, a prostaglandin metabolism is assessed. {yields} RhoA activation increases PGE{sub 2} levels and its metabolic enzyme mPGES-1. {yields} RhoA-activated NF-{kappa}B and EGR-1 are positively involved in mPGES-1 induction. -- Abstract: Oncogenic RhoA GTPase has been investigated as a mediator of pro-inflammatory responses and aggressive carcinogenesis. Among the various targets of RhoA-linked signals, pro-inflammatory prostaglandin E{sub 2} (PGE{sub 2}), a major prostaglandin metabolite, was assessed in epithelial cancer cells. RhoA activation increased PGE{sub 2} levels and gene expression of the rate-limiting PGE{sub 2} producing enzymes, cyclooxygenase-2 and microsomal prostaglandin E synthase 1 (mPGES-1). In particular, human mPGES-1 was induced by RhoA via transcriptional activation in control and interleukin (IL)-1{beta}-activated cancer cells. To address the involvement of potent signaling pathways in RhoA-activated mPGES-1 induction, various signaling inhibitors were screened for their effects on mPGES-1 promoter activity. RhoA activation enhanced basal and IL-1{beta}-mediated phosphorylated nuclear factor-{kappa}B and extracellular signal-regulated kinase1/2 proteins, all of which were positively involved in RhoA-induced gene expression of mPGES-1. As one potent down-stream transcription factor of ERK1/2 signals, early growth response gene 1 product also mediated RhoA-induced gene expression of mPGES-1 by enhancing transcriptional activity. Since oncogene-triggered PGE{sub 2} production is a critical modulator of epithelial tumor cells, RhoA-associated mPGES-1 represents a promising chemo-preventive or therapeutic target for epithelial inflammation and its associated cancers.

The Prevention of Hereditary Breast and Ovarian Cancer: A Personal View

Directory of Open Access Journals (Sweden)

Narod Steven

2004-02-01

Full Text Available Abstract Options for the prevention of hereditary breast and ovarian cancer include screening, preventive surgery and chemoprevention. Screening studies with magnetic resonance imaging of the breast are promising but the technology is not widespread and MRI is unlikely to be available as a screening tool in the near future. Prophylactic oophorectomy and mastectomy are effective preventive measures and are gaining in acceptance by patients and physicians. Preventive mastectomy is effective against both primary and contralateral breast cancer. Oophorectomy prevents ovarian cancer, and if done prior to menopause, will prevent breast cancer as well. Tamoxifen has been shown to prevent contralateral breast cancers in BRCA1 and BRCA2 carriers but is not widely accepted as a means of primary prevention. Oral contraceptives and tubal ligation will reduce the risk of hereditary ovarian cancer and should be considered in women who wish to retain ovarian function.

Long Term Exposure to Polyphenols of Artichoke (Cynara scolymus L.) Exerts Induction of Senescence Driven Growth Arrest in the MDA-MB231 Human Breast Cancer Cell Line.

Science.gov (United States)

Mileo, Anna Maria; Di Venere, Donato; Abbruzzese, Claudia; Miccadei, Stefania

2015-01-01

Polyphenolic extracts from the edible part of artichoke (Cynara scolymus L.) have been shown to be potential chemopreventive and anticancer dietary compounds. High doses of polyphenolic extracts (AEs) induce apoptosis and decrease the invasive potential of the human breast cancer cell line, MDA-MB231. However, the molecular mechanism underlying AEs antiproliferative effects is not completely understood. We demonstrate that chronic and low doses of AEs treatment at sublethal concentrations suppress human breast cancer cell growth via a caspases-independent mechanism. Furthermore, AEs exposure induces a significant increase of senescence-associated β-galactosidase (SA-β-gal) staining and upregulation of tumour suppressor genes, p16(INK4a) and p21(Cip1/Waf1) in MDA-MB231 cells. AEs treatment leads to epigenetic alterations in cancer cells, modulating DNA hypomethylation and lysine acetylation levels in total proteins. Cell growth arrest correlates with increased reactive oxygen species (ROS) production in AEs treated breast cancer cells. Inhibition of ROS generation by N-acetylcysteine (NAC) attenuates the antiproliferative effect. These findings demonstrate that chronic AEs treatment inhibits breast cancer cell growth via the induction of premature senescence through epigenetic and ROS-mediated mechanisms. Our results suggest that artichoke polyphenols could be a promising dietary tool either in cancer chemoprevention or/and in cancer treatment as a nonconventional, adjuvant therapy.

Environmental Epigenetics: Crossroad between Public Health, Lifestyle, and Cancer Prevention

Science.gov (United States)

Romani, Massimo; Pistillo, Maria Pia; Banelli, Barbara

2015-01-01

Epigenetics provides the key to transform the genetic information into phenotype and because of its reversibility it is considered an ideal target for therapeutic interventions. This paper reviews the basic mechanisms of epigenetic control: DNA methylation, histone modifications, chromatin remodeling, and ncRNA expression and their role in disease development. We describe also the influence of the environment, lifestyle, nutritional habits, and the psychological influence on epigenetic marks and how these factors are related to cancer and other diseases development. Finally we discuss the potential use of natural epigenetic modifiers in the chemoprevention of cancer to link together public health, environment, and lifestyle. PMID:26339624

Arctigenin in combination with quercetin synergistically enhances the antiproliferative effect in prostate cancer cells.

Science.gov (United States)

Wang, Piwen; Phan, Tien; Gordon, David; Chung, Seyung; Henning, Susanne M; Vadgama, Jaydutt V

2015-02-01

We investigated whether a combination of two promising chemopreventive agents arctigenin (Arc) and quercetin (Q) increases the anticarcinogenic potency at lower concentrations than necessary when used individually in prostate cancer. Androgen-dependent LAPC-4 and LNCaP prostate cancer cells were treated with low doses of Arc and Q alone or in combination for 48 h. The antiproliferative activity of Arc was 10- to 20-fold stronger than Q in both cell lines. Their combination synergistically enhanced the antiproliferative effect, with a stronger effect in androgen receptor (AR) wild-type LAPC-4 cells than in AR mutated LNCaP cells. Arc demonstrated a strong ability to inhibit AR protein expression in LAPC-4 cells. The combination treatment significantly inhibited both AR and PI3K/Akt pathways compared to control. A protein array analysis revealed that the mixture targets multiple pathways particularly in LAPC-4 cells including Stat3 pathway. The mixture significantly inhibited the expression of several oncogenic microRNAs including miR-21, miR-19b, and miR-148a compared to control. The mixture also enhanced the inhibition of cell migration in both cell lines compared to individual compounds tested. The combination of Arc and Q that target similar pathways, at low physiological doses, provides a novel regimen with enhanced chemoprevention in prostate cancer. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Therapeutic Enzymes: Applications and Approaches to Pharmacological Improvement.

Science.gov (United States)

Yari, Maryam; Ghoshoon, Mohammad B; Vakili, Bahareh; Ghasemi, Younes

2017-01-01

Among therapeutic proteins, enzymes represent small and of course profitable market. They can be used to treat important, rare, and deadly diseases. Enzyme therapy is the only available treatment for certain disorders. Here, pharmaceutical enzymes are reviewed. They are categorized in four main groups, enzymes in replacement therapy, enzymes in cancer treatment, enzymes for fibrinolysis, and finally enzymes that are used topically for various treatments. Furthermore, enzyme gene therapy and future perspective of therapeutic enzymes are mentioned in brief. There are many important approved enzymes in pharmaceutical market. Several approaches such as point mutation, fusion protein designing, glycoengineering, and PEGylation were used to achieve improved enzymes. Although sometimes enzymes were engineered to facilitate production and purification process, appropriate delivery to target sites, extending half-life, and reducing immunogenicity are among the main goals of engineering approaches. Overall, enzymes play a critical role in treatment of common and rare diseases. Evaluation of new enzymes as well as improvement of approved enzymes are of the most important challenges in biotechnology. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Ameliorating effect of wheat bran, Beta-carotene and Curcumin on K-ras gene mutations and expression of ntioxidant enzymes in rat colon cancer

International Nuclear Information System (INIS)

Tarek Elmaghraby, T.; Korraa, S.S.; Maher, M.M.; Hassan, N.H.A.

2010-01-01

In Egypt, colon cancer has unique characterises differ than other countries, more than third cases happen in people under 40 years, with advanced stage, high grade tumors that carry more mutations . This may be return to increase pollution in food and water. The aim of the present study, is the investigation of the role of some natural products approaches for colorectal carcinoma including curcumin, wheat bran and β-Carotene. Accordingly, animals were injected with 1,2-dimethylhydrazine hydrochloride (DMH) and/or dually exposed to ionizing radiation to induce colorectal cancer. The frequency of mutation of K-ras gene, the level activity of SOD, GpX antioxidant enzymes and expression of SOD1, SOD2 and GpX1 in tissue of 120 colon rats from 10 different treated groups were studied. Curcumin, wheat bran and D-carotene have inhibition effect on formation of colon cancer and decrease the mutations in K-ras gene. Moreover, they have ameliorating effect on antioxidants enzymes activities and expressions. The present study revealed that wheat bran and D-carotene have better effect than curcumin.

A novel NSAID derivative, phospho-ibuprofen, prevents AOM-induced colon cancer in rats

Science.gov (United States)

OUYANG, NENGTAI; JI, PING; WILLIAMS, JENNIE L.

2013-01-01

The cancer chemopreventive properties and gastrointestinal toxicity of ibuprofen are well documented. Modification of existing NSAIDs has improved on the chemopreventive efficacy of this agent and reduced its toxicity. In this study, ibuprofen and a modified derivative (phospho-modified ibuprofen or p-ibuprofen) were used in a chemically induced model of colon cancer. Fisher 344 rats were injected with azoxymethane then treated with either ibuprofen (500 ppm) or p-ibuprofen (900 ppm) for 20 weeks to observe aberrant crypt foci (ACF) or 40 weeks to evaluate tumor incidence and multiplicity. β-catenin and p65 were measured in colonic tissues by immunofluorescence staining. Equal molar doses of ibuprofen (75 and 670 mg/kg) and p-ibuprofen (135 and 1,215 mg/kg) were administered to rats for 7 days to assess acute toxicity. The in vitro effect of p-ibuprofen on COX-2 and PGE2 synthesis, β-catenin expression and NF-κB activity were examined in RAW 264.7 macrophage and HCT 116 colon cancer cells. At week 20, p-ibuprofen and ibuprofen significantly reduced the multiplicity of ACF compared with control (pibuprofen and ibuprofen reduced the multiplicity of colon tumors compared with control (pibuprofen (670 mg/kg) and p-ibuprofen (1,215 mg/kg) resulted in stomach ulceration in 85.7% (6 out of 7) and 14.3% (1 out of 7) of rats, respectively, with pibuprofen and p-ibuprofen suppressed β-catenin nuclear translocation in colon cancer cells. In addition, p-ibuprofen but not ibuprofen inhibited NF-κB activation in colon cancer cells. Collectively, these results suggest that p-ibuprofen is a potential effective novel drug for long-term use in colon cancer prevention. PMID:23291777

Nicotine-mediated suppression of the retinoic acid metabolizing enzyme CYP26A1 limits the oncogenic potential of breast cancer.

Science.gov (United States)

Osanai, Makoto; Lee, Gang-Hong

2011-06-01

Tobacco smoke influences cancer development in tissues that are not directly exposed, and epidemiological studies have indicated that smoking women might experience decreased risk of breast cancer as a result of antiestrogenic effects. However, it remains to be clarified whether nicotine, one of the major addictive and best-investigated constituents of tobacco smoke, has any effect on breast cancer. Our recent work demonstrated that the retinoic acid metabolizing enzyme CYP26A1 enhances oncogenic and cell survival properties of breast carcinoma cells, implying a role as an oncogene. Here, we present evidence that nicotine significantly suppresses constitutive expression of CYP26A1, and that cells treated with nicotine exhibit enhanced sensitivity to apoptosis. In addition, nicotine may inhibit anchorage independent growth, cellular invasiveness and motility. These data show that nicotine can limit CYP26A1-mediated oncogenic characteristics, and suggest mechanisms by which nicotine might inhibit breast cancer development. © 2011 Japanese Cancer Association.

In vivo examination of the effects of hydroxycinnamic acid on xenobiotic metabolizing and antioxidant enzymes

Directory of Open Access Journals (Sweden)

Semiz Asli

2017-01-01

Full Text Available In the last decade, hydroxycinnamic acids (HCA have gained increasing attention from researchers due to their antioxidant potential. The aim of this study was to examine in detail the impact of dietary HCA on particular types of P450 and also selected phase II and antioxidant enzymes in Wistar rat. HCA (10 mM/kg/day, i.p. was administered for ten continuous days. Examination of the activities and mRNA and protein levels revealed that CYP2B, 2C6 and 3A enzyme activities were not altered significantly, with Western blot and qRT-PCR results corroborating this result. While treatment with HCA led to a significant reduction in CYP1A1/CYP1A2-associated enzyme activities, CYP1A1 protein, and mRNA levels were found to be unchanged. Aromatase (CYP19 activity, as well as protein and mRNA levels, were significantly reduced with HCA treatment. On the other hand, the NAD(PH:quinone oxidoreductase 1 (NQO1, catalase (CAT, glutathione peroxidase (GPx and glutathione S-transferases (GSTs activities were increased significantly. Also, HCA treatment significantly increased the GST-mu and GST-theta mRNA levels. These observations may be of importance given the potential use of HCA as a chemopreventive and as an anticancer agent.

Use of antidepressants and risk of epithelial ovarian cancer

DEFF Research Database (Denmark)

Mørch, Lina S; Dehlendorff, Christian; Baandrup, Louise

2017-01-01

antidepressants, selective serotonin reuptake inhibitors, other antidepressants, and potential confounder drugs), medical and reproductive history and socioeconomic parameters, were obtained from nationwide registries. We used conditional logistic regression models to estimate adjusted odds ratios (ORs) and two.......80 (95% CI, 0.60-1.08). Among postmenopausal women, the inverse association was restricted to users of menopausal hormone therapy. In conclusion, use of selective serotonin reuptake inhibitors was associated with a decreased risk of epithelial ovarian cancer; thereby implying potential chemopreventive...

Role of GSK-3β in Regulation of Canonical Wnt/β-catenin Signaling and PI3-K/Akt Oncogenic Pathway in Colon Cancer.

Science.gov (United States)

Jain, Shelly; Ghanghas, Preety; Rana, Chandan; Sanyal, S N

2017-08-09

Non-steroidal anti-inflammatory drugs (NSAIDs) are emerging as novel chemopreventive agents because of their ability in blocking cellular proliferation, and thereby tumor development, and also by promoting apoptosis. GSK-3β, a serine threonine kinase and a negative regulator of the oncogenic Wnt/β-catenin signaling pathway, plays a critical role in the regulation of oncogenesis. Celecoxib and etoricoxib, the two cyclooxygenase-2 (COX-2) selective NSAIDs, and Diclofenac, a preferential COX-2 inhibitory NSAID, had shown uniformly the chemopreventive and anti-neoplastic effects in the early stage of colon cancer by promoting apoptosis as well as an over-expression of GSK-3β while down-regulating the PI3-K/Akt oncogenic pathway.

Water-soluble nanoconjugates of quantum dot-chitosan-antibody for in vitro detection of cancer cells based on “enzyme-free” fluoroimmunoassay

Energy Technology Data Exchange (ETDEWEB)

Mansur, Herman S., E-mail: hmansur@demet.ufmg.br [Center of Nanoscience, Nanotechnology, and Innovation-CeNano" 2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG, Av. Presidente Antônio Carlos, 6627, Belo Horizonte, MG 31.270-901 (Brazil); Mansur, Alexandra A.P. [Center of Nanoscience, Nanotechnology, and Innovation-CeNano" 2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG, Av. Presidente Antônio Carlos, 6627, Belo Horizonte, MG 31.270-901 (Brazil); Soriano-Araújo, Amanda [Center of Nanoscience, Nanotechnology, and Innovation-CeNano" 2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG, Av. Presidente Antônio Carlos, 6627, Belo Horizonte, MG 31.270-901 (Brazil); Department of Preventive Veterinary Medicine, Veterinary School, UFMG (Brazil); Lobato, Zélia I.P. [Department of Preventive Veterinary Medicine, Veterinary School, UFMG (Brazil); Carvalho, Sandhra M. de [Center of Nanoscience, Nanotechnology, and Innovation-CeNano" 2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG, Av. Presidente Antônio Carlos, 6627, Belo Horizonte, MG 31.270-901 (Brazil); Department of Physiology and Biophysics, ICB, UFMG (Brazil); Leite, Maria de Fatima [Department of Physiology and Biophysics, ICB, UFMG (Brazil)

2015-07-01

Cancer remains one of the world's most devastating diseases with millions of fatalities and new cases every year. In this work, we attempted to develop a facile “enzyme-free” fluoroimmunoassay based on the novel nanoconjugates composed of CdS quantum dots (QDs) as the fluorescent inorganic core and an antibody-modified polysaccharide as the organic shell, modeling their possible application for the in vitro diagnosis of non-Hodgkin lymphoma (NHL) cancer. Chitosan was conjugated with an anti-CD20 polyclonal antibody (pAbCD20) by the formation of covalent amide bonds. In the sequence, these chitosan-antibody conjugates were utilized as direct ligands for the surface biofunctionalization of CdS QDs (CdS/chitosan-pAbCD20) using a single-step colloidal process in aqueous medium at room temperature. The most relevant physico-chemical properties of these nanoconjugates were assessed by morphological and spectroscopic techniques. The results indicated that CdS nanocrystals were produced with an average diameter of 2.5 nm and with cubic zinc blende crystalline nanostructure. The CdS-immunoconjugates (CdS/chitosan-pAbCD20) presented colloidal hydrodynamic diameter (H{sub D}) of 15.0 ± 1.2 nm. In addition, the results evidenced that the “enzyme-free” QD-linked immunosorbent assay (QLISA) was effective for the in vitro detection against the antigen CD20 (aCD20) based on fluorescent behavior of the CdS nanoconjugates. Moreover, the CdS-immunoconjugates were successfully used for fluorescence bioimaging of NHL cancer cells. Finally, the cell viability results using different cell cultures based on LDH, MTT and Resazurin bio-assays have demonstrated no cytotoxicity of the new CdS-chitosan bioconjugates relative to the standard controls. Thus, CdS conjugates may offer a promising platform for the future development of in vitro and in vivo applications for the detection and diagnosis of NHL cancer cells. - Highlights: • CdS quantum dots (QDs) were prepared using

Arctigenin in combination with quercetin synergistically enhances the anti-proliferative effect in prostate cancer cells

Science.gov (United States)

Wang, Piwen; Phan, Tien; Gordon, David; Chung, Seyung; Henning, Susanne M.; Vadgama, Jaydutt V.

2014-01-01

Scope We investigated whether a combination of two promising chemopreventive agents arctigenin and quercetin increases the anti-carcinogenic potency at lower concentrations than necessary when used individually in prostate cancer. Methods and results Androgen-dependent LAPC-4 and LNCaP prostate cancer cells were treated with low doses of arctigenin and quercetin alone or in combination for 48h. The anti-proliferative activity of arctigenin was 10-20 fold stronger than quercetin in both cell lines. Their combination synergistically enhanced the anti-proliferative effect, with a stronger effect in androgen receptor (AR) wild-type LAPC-4 cells than in AR mutated LNCaP cells. Arctigenin demonstrated a strong ability to inhibit AR protein expression in LAPC-4 cells. The combination treatment significantly inhibited both AR and PI3K/Akt pathways compared to control. A protein array analysis revealed that the mixture targets multiple pathways particularly in LAPC-4 cells including Stat3 pathway. The mixture significantly inhibited the expression of several oncogenic microRNAs including miR-21, miR-19b, and miR-148a compared to control. The mixture also enhanced the inhibition of cell migration in both cell lines compared to individual compounds tested. Conclusion The combination of arctigenin and quercetin, that target similar pathways, at low physiological doses, provides a novel regimen with enhanced chemoprevention in prostate cancer. PMID:25380086

Inhibitory effect of Epstein-Barr virus activation by Citrus fruits, a cancer chemopreventor.

Science.gov (United States)

Iwase, Y; Takemura, Y; Ju-ichi, M; Kawaii, S; Yano, M; Okuda, Y; Mukainaka, T; Tsuruta, A; Okuda, M; Takayasu, J; Tokuda, H; Nishino, H

1999-05-24

To search useful compounds in Citrus fruit for cancer chemoprevention, we carried out a primary screening of extracts of fruit peels and seeds from 78 species of the genus Citrus and those from two Fortunella and one Poncirus species, which were closely related to the genus Citrus. These Citrus extracts inhibited the Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol 13-acetate (TPA) as a useful screening method for anti-tumor promoters. Our results indicated that Citrus containing substances may be inhibit susceptibility factors involved in the events leading to the development of cancer.

Insulin-Sensitizers, Polycystic Ovary Syndrome and Gynaecological Cancer Risk

Science.gov (United States)

Lauretta, Rosa; Lanzolla, Giulia; Vici, Patrizia; Mariani, Luciano; Moretti, Costanzo

2016-01-01

Preclinical, early phase clinical trials and epidemiological evidence support the potential role of insulin-sensitizers in cancer prevention and treatment. Insulin-sensitizers improve the metabolic and hormonal profile in PCOS patients and may also act as anticancer agents, especially in cancers associated with hyperinsulinemia and oestrogen dependent cancers. Several lines of evidence support the protection against cancer exerted by dietary inositol, in particular inositol hexaphosphate. Metformin, thiazolidinediones, and myoinositol postreceptor signaling may exhibit direct inhibitory effects on cancer cell growth. AMPK, the main molecular target of metformin, is emerging as a target for cancer prevention and treatment. PCOS may be correlated to an increased risk for developing ovarian and endometrial cancer (up to threefold). Several studies have demonstrated an increase in mortality rate from ovarian cancer among overweight/obese PCOS women compared with normal weight women. Long-term use of metformin has been associated with lower rates of ovarian cancer. Considering the evidence supporting a higher risk of gynaecological cancer in PCOS women, we discuss the potential use of insulin-sensitizers as a potential tool for chemoprevention, hypothesizing a possible rationale through which insulin-sensitizers may inhibit tumourigenesis. PMID:27725832

Chemical Probes of Rapid Estrogen Signaling in Breast Cancer Treatment and Chemoprevention

National Research Council Canada - National Science Library

Weatherman, Rose V

2007-01-01

The goal of this project was to design new chemical tools to selectively probe the molecular mechanisms of action of rapid estrogen receptor action and their relevance to breast cancer drugs like tamoxifen...

The feasibility of enzyme targeted activation for amino acid/dipeptide monoester prodrugs of floxuridine; cathepsin D as a potential targeted enzyme.

Science.gov (United States)

Tsume, Yasuhiro; Amidon, Gordon L

2012-03-26

The improvement of therapeutic efficacy for cancer agents has been a big challenge which includes the increase of tumor selectivity and the reduction of adverse effects at non-tumor sites. In order to achieve those goals, prodrug approaches have been extensively investigated. In this report, the potential activation enzymes for 5'-amino acid/dipeptide monoester floxuridine prodrugs in pancreatic cancer cells were selected and the feasibility of enzyme specific activation of prodrugs was evaluated. All prodrugs exhibited the range of 3.0-105.7 min of half life in Capan-2 cell homogenate with the presence and the absence of selective enzyme inhibitors. 5'-O-L-Phenylalanyl-L-tyrosyl-floxuridine exhibited longer half life only with the presence of pepstatin A. Human cathepsin B and D selectively hydrolized 5'-O-L-phenylalanyl-L-tyrosylfloxuridine and 5'-O-L-phenylalanyl-L-glycylfloxuridine compared to the other tested prodrugs. The wide range of growth inhibitory effect by floxuridine prodrugs in Capan-2 cells was observed due to the different affinities of prodrug promoieties to enzymes. In conclusion, it is feasible to design prodrugs which are activated by specific enzymes. Cathepsin D might be a good candidate as a target enzyme for prodrug activation and 5'-O-L-phenylalanyl-L-tyrosylfloxuridine may be the best candidate among the tested floxuridine prodrugs.

Trial watch – inhibiting PARP enzymes for anticancer therapy

Science.gov (United States)

Sistigu, Antonella; Manic, Gwenola; Obrist, Florine; Vitale, Ilio

2016-01-01

ABSTRACT Poly(ADP-ribose) polymerases (PARPs) are a members of family of enzymes that catalyze poly(ADP-ribosyl)ation (PARylation) and/or mono(ADP-ribosyl)ation (MARylation), two post-translational protein modifications involved in crucial cellular processes including (but not limited to) the DNA damage response (DDR). PARP1, the most abundant family member, is a nuclear protein that is activated upon sensing distinct types of DNA damage and contributes to their resolution by PARylating multiple DDR players. Recent evidence suggests that, along with DDR, activated PARP1 mediates a series of prosurvival and proapoptotic processes aimed at preserving genomic stability. Despite this potential oncosuppressive role, upregulation and/or overactivation of PARP1 or other PARP enzymes has been reported in a variety of human neoplasms. Over the last few decades, several pharmacologic inhibitors of PARP1 and PARP2 have been assessed in preclinical and clinical studies showing potent antineoplastic activity, particularly against homologous recombination (HR)-deficient ovarian and breast cancers. In this Trial Watch, we describe the impact of PARP enzymes and PARylation in cancer, discuss the mechanism of cancer cell killing by PARP1 inactivation, and summarize the results of recent clinical studies aimed at evaluating the safety and therapeutic profile of PARP inhibitors in cancer patients. PMID:27308587

Oral Field Cancerization: A Review

Directory of Open Access Journals (Sweden)

Raviraj Jayam

2010-01-01

Full Text Available The concept of oral field cancerization (OFC has been ever changing since its first description by Slaughter et al in 1953. The concept of OFC explains the mechanisms by which second primary tumors (OPTs develop- OPTs are the tumor-, which develop in the oral cavity in succession to the primary malignant tumors, which might vary in duration ranging from few months to years. The "classical" mechanism, which was originally observed by Slaughter describes that in the individuals with adverse habits, large areas of the aerodigestive tissue are affected by long-term exposure to carcinogens. In this preconditioned epithelium, multifocal carcinomas can develop as a result of independent mutations, and thus would not be genetically related. Although this mechanism was accepted for a quite a long time, the controversies began with the advent of new mechanism called the "clonal theory-, which explains that a single cell, on exposure to carcinogens, is transformed and give- rise to one large extended premalignant field by clonal expansion and gradual replacement of normal mucosa. In this field of various subclones, two separate tumors can develop after accumulation of additional genetic alteration-. Both tumors have the same clonal origin, and would thus share at least one early genetic event, which occurred before the initial clonal expansion. Also, the molecular studies regarding OFC have been expanding exponentially since a few years. The need for chemoprevention and the management of OFC with its resultant effect of development of second primary tumors has been challenging till today. Hence, the article tries to explain the conflicting aspects of various mechanisms by which SPTs develop, the molecular techniques, chemoprevention and therapeutic implications for oral field cancerization.

Enzymes in Poultry and Swine Nutrition | CRDI - Centre de ...

International Development Research Centre (IDRC) Digital Library (Canada)

Book cover Enzymes in Poultry and Swine Nutrition. Auteur(s) : Ronald R. ... mechanisms. Such studies will enhance our understanding of the role of dietary enzymes in animal nutrition. ... Six équipes de chercheurs de classe mondiale étudieront comment surmonter la résistance au traitement des cancers les plus mortels.

Glutamine deficiency induces DNA alkylation damage and sensitizes cancer cells to alkylating agents through inhibition of ALKBH enzymes.

Directory of Open Access Journals (Sweden)

Thai Q Tran

2017-11-01

Full Text Available Driven by oncogenic signaling, glutamine addiction exhibited by cancer cells often leads to severe glutamine depletion in solid tumors. Despite this nutritional environment that tumor cells often experience, the effect of glutamine deficiency on cellular responses to DNA damage and chemotherapeutic treatment remains unclear. Here, we show that glutamine deficiency, through the reduction of alpha-ketoglutarate, inhibits the AlkB homolog (ALKBH enzymes activity and induces DNA alkylation damage. As a result, glutamine deprivation or glutaminase inhibitor treatment triggers DNA damage accumulation independent of cell death. In addition, low glutamine-induced DNA damage is abolished in ALKBH deficient cells. Importantly, we show that glutaminase inhibitors, 6-Diazo-5-oxo-L-norleucine (DON or CB-839, hypersensitize cancer cells to alkylating agents both in vitro and in vivo. Together, the crosstalk between glutamine metabolism and the DNA repair pathway identified in this study highlights a potential role of metabolic stress in genomic instability and therapeutic response in cancer.

Glutamine deficiency induces DNA alkylation damage and sensitizes cancer cells to alkylating agents through inhibition of ALKBH enzymes.

Science.gov (United States)

Tran, Thai Q; Ishak Gabra, Mari B; Lowman, Xazmin H; Yang, Ying; Reid, Michael A; Pan, Min; O'Connor, Timothy R; Kong, Mei

2017-11-01

Driven by oncogenic signaling, glutamine addiction exhibited by cancer cells often leads to severe glutamine depletion in solid tumors. Despite this nutritional environment that tumor cells often experience, the effect of glutamine deficiency on cellular responses to DNA damage and chemotherapeutic treatment remains unclear. Here, we show that glutamine deficiency, through the reduction of alpha-ketoglutarate, inhibits the AlkB homolog (ALKBH) enzymes activity and induces DNA alkylation damage. As a result, glutamine deprivation or glutaminase inhibitor treatment triggers DNA damage accumulation independent of cell death. In addition, low glutamine-induced DNA damage is abolished in ALKBH deficient cells. Importantly, we show that glutaminase inhibitors, 6-Diazo-5-oxo-L-norleucine (DON) or CB-839, hypersensitize cancer cells to alkylating agents both in vitro and in vivo. Together, the crosstalk between glutamine metabolism and the DNA repair pathway identified in this study highlights a potential role of metabolic stress in genomic instability and therapeutic response in cancer.

Nanoparticle Delivery of Natural Products in the Prevention and Treatment of Cancers: Current Status and Future Prospects

Energy Technology Data Exchange (ETDEWEB)

Bharali, Dhruba J. [The Pharmaceutical Research Institute at Albany College of Pharmacy and Health Sciences, 1 Discovery Drive, Rensselaer, NY 12144 (United States); Siddiqui, Imtiaz A.; Adhami, Vaqar M.; Chamcheu, Jean Christopher [Department of Dermatology, University of Wisconsin, Madison, WI 53706 (United States); Aldahmash, Abdullah M. [Stem Cell Unit, College of Medicine, King Saud University, Riyadh, 11461 (Saudi Arabia); University Hospital of Odense & Medical Biotechnology Center, Winslowsparken 25, DK-5000, Odense (Denmark); Mukhtar, Hasan [Department of Dermatology, University of Wisconsin, Madison, WI 53706 (United States); Mousa, Shaker A., E-mail: shaker.mousa@acphs.edu [The Pharmaceutical Research Institute at Albany College of Pharmacy and Health Sciences, 1 Discovery Drive, Rensselaer, NY 12144 (United States); Stem Cell Unit, College of Medicine, King Saud University, Riyadh, 11461 (Saudi Arabia)

2011-10-26

The advent of nanotechnology has had a revolutionary impact on many aspects of 21{sup st} century life. Nanotechnology has provided an opportunity to explore new avenues that conventional technologies have been unable to make an impact on for diagnosis, prevention, and therapy of different diseases, and of cancer in particular. Entities in nanometer sizes are excellent platforms to incorporate various drugs or active materials that can be delivered effectively to the desired action site without compromising the activity of the incorporated drug or material. In particular, nanotechnology entities can be used to deliver conventional natural products that have poor solubility or a short half life. Conventional natural products used with entities in nanometer sizes enable us to solve many of the inherent problems (stability, solubility, toxicity) associated with natural products, and also provide a platform for targeted delivery to tumor sites. We recently introduced the novel concept of using nanotechnology for enhancing the outcome of chemoprevention, which we called ‘nanochemoprevention’. This idea was subsequently exploited by several laboratories worldwide and has now become an advancing field in chemoprevention research. This review examines some of the applications of nanotechnology for cancer prevention and therapy using natural products.

Nanoparticle Delivery of Natural Products in the Prevention and Treatment of Cancers: Current Status and Future Prospects

International Nuclear Information System (INIS)

Bharali, Dhruba J.; Siddiqui, Imtiaz A.; Adhami, Vaqar M.; Chamcheu, Jean Christopher; Aldahmash, Abdullah M.; Mukhtar, Hasan; Mousa, Shaker A.

2011-01-01

The advent of nanotechnology has had a revolutionary impact on many aspects of 21 st century life. Nanotechnology has provided an opportunity to explore new avenues that conventional technologies have been unable to make an impact on for diagnosis, prevention, and therapy of different diseases, and of cancer in particular. Entities in nanometer sizes are excellent platforms to incorporate various drugs or active materials that can be delivered effectively to the desired action site without compromising the activity of the incorporated drug or material. In particular, nanotechnology entities can be used to deliver conventional natural products that have poor solubility or a short half life. Conventional natural products used with entities in nanometer sizes enable us to solve many of the inherent problems (stability, solubility, toxicity) associated with natural products, and also provide a platform for targeted delivery to tumor sites. We recently introduced the novel concept of using nanotechnology for enhancing the outcome of chemoprevention, which we called ‘nanochemoprevention’. This idea was subsequently exploited by several laboratories worldwide and has now become an advancing field in chemoprevention research. This review examines some of the applications of nanotechnology for cancer prevention and therapy using natural products

The chemopreventive activity of the histone deacetylase inhibitor tributyrin in colon carcinogenesis involves the induction of apoptosis and reduction of DNA damage

Energy Technology Data Exchange (ETDEWEB)

Heidor, Renato [Laboratory of Diet, Nutrition and Cancer, Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo (Brazil); Advanced Research Center in Food Science and Nutrition (NAPAN) and Food Research Center (FoRC), Faculty of Pharmaceutical Sciences, University of São Paulo (Brazil); Furtado, Kelly Silva; Ortega, Juliana Festa [Laboratory of Diet, Nutrition and Cancer, Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo (Brazil); Oliveira, Tiago Franco de [Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo (Brazil); Tavares, Paulo Eduardo Latorre Martins; Vieira, Alessandra; Miranda, Mayara Lilian Paulino [Laboratory of Diet, Nutrition and Cancer, Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo (Brazil); Purgatto, Eduardo [Laboratory of Food Chemistry and Biochemistry, Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo (Brazil); Advanced Research Center in Food Science and Nutrition (NAPAN) and Food Research Center (FoRC), Faculty of Pharmaceutical Sciences, University of São Paulo (Brazil); Moreno, Fernando Salvador, E-mail: rmoreno@usp.br [Laboratory of Diet, Nutrition and Cancer, Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo (Brazil); Advanced Research Center in Food Science and Nutrition (NAPAN) and Food Research Center (FoRC), Faculty of Pharmaceutical Sciences, University of São Paulo (Brazil)

2014-04-15

The chemopreventive activity of the histone deacetylase inhibitor (HDACi) tributyrin (TB), a prodrug of butyric acid (BA), was evaluated in a rat model of colon carcinogenesis. The animals were treated with TB (TB group: 200 mg/100 g of body weight, b.w.) or maltodextrin (MD isocaloric control group: 300 mg/100 g b.w.) daily for 9 consecutive weeks. In the 3rd and 4th weeks of treatment, the rats in the TB and MD groups were given DMH (40 mg/kg b.w.) twice a week. After 9 weeks, the animals were euthanized, and the distal colon was examined. Compared with the control group (MD group), TB treatment reduced the total number of aberrant crypt foci (ACF; p < 0.05) as well as the ACF with ≥ 4 crypts (p < 0.05), which are considered more aggressive, but not inhibited the formation of DMH-induced O6-methyldeoxyguanosine DNA adducts. The TB group also showed a higher apoptotic index (p < 0.05) and reduced DNA damage (p < 0.05) compared with MD group. TB acted as a HDACi, as rats treated with the prodrug of BA had higher levels of histone H3K9 acetylation compared with the MD group (p < 0.05). TB administration resulted in increased colonic tissue concentrations of BA (p < 0.05) compared with the control animals. These results suggest that TB can be considered a promising chemopreventive agent for colon carcinogenesis because it reduced the number of ACF, including those that were more aggressive. Induction of apoptosis and reduction of DNA damage are cellular mechanisms that appear to be involved in the chemopreventive activity of TB. - Highlights: • Tributyrin is a chemopreventive agent for rat colon aberrant crypt foci. • Tributyrin increased apoptosis in an experimental rat colon carcinogenesis model. • Tributyrin treatment in a rat colon carcinogenesis model decreased DNA damage. • Tributyrin treatment induced H3K9 acetylation in a rat colon carcinogenesis model.

The chemopreventive activity of the histone deacetylase inhibitor tributyrin in colon carcinogenesis involves the induction of apoptosis and reduction of DNA damage

International Nuclear Information System (INIS)

Heidor, Renato; Furtado, Kelly Silva; Ortega, Juliana Festa; Oliveira, Tiago Franco de; Tavares, Paulo Eduardo Latorre Martins; Vieira, Alessandra; Miranda, Mayara Lilian Paulino; Purgatto, Eduardo; Moreno, Fernando Salvador

2014-01-01

The chemopreventive activity of the histone deacetylase inhibitor (HDACi) tributyrin (TB), a prodrug of butyric acid (BA), was evaluated in a rat model of colon carcinogenesis. The animals were treated with TB (TB group: 200 mg/100 g of body weight, b.w.) or maltodextrin (MD isocaloric control group: 300 mg/100 g b.w.) daily for 9 consecutive weeks. In the 3rd and 4th weeks of treatment, the rats in the TB and MD groups were given DMH (40 mg/kg b.w.) twice a week. After 9 weeks, the animals were euthanized, and the distal colon was examined. Compared with the control group (MD group), TB treatment reduced the total number of aberrant crypt foci (ACF; p < 0.05) as well as the ACF with ≥ 4 crypts (p < 0.05), which are considered more aggressive, but not inhibited the formation of DMH-induced O6-methyldeoxyguanosine DNA adducts. The TB group also showed a higher apoptotic index (p < 0.05) and reduced DNA damage (p < 0.05) compared with MD group. TB acted as a HDACi, as rats treated with the prodrug of BA had higher levels of histone H3K9 acetylation compared with the MD group (p < 0.05). TB administration resulted in increased colonic tissue concentrations of BA (p < 0.05) compared with the control animals. These results suggest that TB can be considered a promising chemopreventive agent for colon carcinogenesis because it reduced the number of ACF, including those that were more aggressive. Induction of apoptosis and reduction of DNA damage are cellular mechanisms that appear to be involved in the chemopreventive activity of TB. - Highlights: • Tributyrin is a chemopreventive agent for rat colon aberrant crypt foci. • Tributyrin increased apoptosis in an experimental rat colon carcinogenesis model. • Tributyrin treatment in a rat colon carcinogenesis model decreased DNA damage. • Tributyrin treatment induced H3K9 acetylation in a rat colon carcinogenesis model

The cysteinyl leukotriene 2 receptor contributes to all-trans retinoic acid-induced differentiation of colon cancer cells

International Nuclear Information System (INIS)

Bengtsson, Astrid M; Jönsson, Gunilla; Magnusson, Cecilia; Salim, Tavga; Axelsson, Cecilia; Sjölander, Anita

2013-01-01

Cysteinyl leukotrienes (CysLTs) are potent pro-inflammatory mediators that are increased in samples from patients with inflammatory bowel diseases (IBDs). Individuals with IBDs have enhanced susceptibility to colon carcinogenesis. In colorectal cancer, the balance between the pro-mitogenic cysteinyl leukotriene 1 receptor (CysLT 1 R) and the differentiation-promoting cysteinyl leukotriene 2 receptor (CysLT 2 R) is lost. Further, our previous data indicate that patients with high CysLT 1 R and low CysLT 2 R expression have a poor prognosis. In this study, we examined whether the balance between CysLT 1 R and CysLT 2 R could be restored by treatment with the cancer chemopreventive agent all-trans retinoic acid (ATRA). To determine the effect of ATRA on CysLT 2 R promoter activation, mRNA level, and protein level, we performed luciferase gene reporter assays, real-time polymerase chain reactions, and Western blots in colon cancer cell lines under various conditions. ATRA treatment induces CysLT 2 R mRNA and protein expression without affecting CysLT 1 R levels. Experiments using siRNA and mutant cell lines indicate that the up-regulation is retinoic acid receptor (RAR) dependent. Interestingly, ATRA also up-regulates mRNA expression of leukotriene C 4 synthase, the enzyme responsible for the production of the ligand for CysLT 2 R. Importantly, ATRA-induced differentiation of colorectal cancer cells as shown by increased expression of MUC-2 and production of alkaline phosphatase, both of which could be reduced by a CysLT 2 R-specific inhibitor. This study identifies a novel mechanism of action for ATRA in colorectal cancer cell differentiation and demonstrates that retinoids can have anti-tumorigenic effects through their action on the cysteinyl leukotriene pathway

Role of pomegranate and citrus fruit juices in colon cancer prevention

Science.gov (United States)

Jaganathan, Saravana Kumar; Vellayappan, Muthu Vignesh; Narasimhan, Gayathri; Supriyanto, Eko

2014-01-01

Colorectal cancer is the second leading cause of cancer-related deaths in the United States. Recent studies prove that though chemotherapeutic agents are being used for the treatment of colon cancer, they become non-effective when the cancer progresses to an invasive stage. Since consumption of certain dietary agents has been linked with various cancers, fruit juices have been investigated for their consistently protective effect against colon cancer. The unique biochemical composition of fruit juices is responsible for their anticancer properties. In this review, the chemo-preventive effect of fruit juices such as pomegranate and citrus juices against colon cancer are discussed. For this purpose, the bioavailability, in vitro and in vivo effects of these fruit juices on colorectal cancer are highlighted. Moreover, there is a scarcity of studies involving human trials to estimate the preventive nature of these juices against colon cancer. This review will support the need for more preclinical tests with these crude juices and their constituents in different colorectal cancer cell lines and also some epidemiological studies in order to have a better understanding and promote pomegranate and citrus juices as crusaders against colon cancer. PMID:24782614

Notch activation is dispensable for D, L-sulforaphane-mediated inhibition of human prostate cancer cell migration.

Directory of Open Access Journals (Sweden)

Eun-Ryeong Hahm

Full Text Available D, L-Sulforaphane (SFN, a synthetic racemic analog of broccoli constituent L-sulforaphane, is a highly promising cancer chemopreventive agent with in vivo efficacy against chemically-induced as well as oncogene-driven cancer in preclinical rodent models. Cancer chemopreventive effect of SFN is characterized by G(2/M phase cell cycle arrest, apoptosis induction, and inhibition of cell migration and invasion. Moreover, SFN inhibits multiple oncogenic signaling pathways often hyperactive in human cancers, including nuclear factor-κB, Akt, signal transducer and activator of transcription 3, and androgen receptor. The present study was designed to determine the role of Notch signaling, which is constitutively active in many human cancers, in anticancer effects of SFN using prostate cancer cells as a model. Exposure of human prostate cancer cells (PC-3, LNCaP, and/or LNCaP-C4-2B to SFN as well as its naturally-occurring thio-, sulfinyl-, and sulfonyl-analogs resulted in cleavage (activation of Notch1, Notch2, and Notch4, which was accompanied by a decrease in levels of full-length Notch forms especially at the 16- and 24-hour time points. The SFN-mediated cleavage of Notch isoforms was associated with its transcriptional activation as evidenced by RBP-Jk-, HES-1A/B- and HEY-1 luciferase reporter assays. Migration of PC-3 and LNCaP cells was decreased significantly by RNA interference of Notch1 and Notch2, but not Notch4. Furthermore, SFN-mediated inhibition of PC-3 and LNCaP cell migration was only marginally affected by knockdown of Notch1 and Notch2. Strikingly, SFN administration to Transgenic Adenocarcinoma of Mouse Prostate transgenic mice failed to increase levels of cleaved Notch1, cleaved Notch2, and HES-1 proteins in vivo in prostatic intraepithelial neoplasia, well-differentiated carcinoma or poorly-differentiated prostate cancer lesions. These results indicate that Notch activation is largely dispensable for SFN-mediated inhibition of cell