Development Of Chemopreventive Drugs Research Articles

Mechanisms of action of plant polyphenols on the initiation of carcinogenesis

Genetic apparatus of human cells is constantly affected by a broad spectrum of mutagenic factors, both exogenous and endogenous. Genetic and epigenetic disorders, which emerge as a result of this influence, become the main cause of the majority of malignant neoplasias. Several different approaches were proposed to prevent these disorders, including the suppression of the activity of mutagenic factors by treatment with certain chemical compounds. Plant polyphenols are promising candidates for the development of chemopreventive drugs, as they exert the ability to regulate the metabolic activation of procarcinogens and modulate the cellular oxidative stress. In the present review, classification of plant phenolic compounds and their interactions with biological macromolecules are described, along with the molecular mechanisms of their influence on the enzymes and regulatory pathways of phase I xenobiotic metabolism, and the prevention of oxidative stress. Interactions between natural polyphenols and patient’s microbiota is also described.

A Relational Database Design for The Compounds Cytotoxically Active on Breast Cancer Cells

Breast cancer is one of the most important global health problems affecting both developed and developing countries. The identification of anticancer compounds, effective on breast cancer cells, is of key importance in chemoprevention investigations and drug development studies. In the literature, there are numerous compounds that have been analyzed for their cytotoxic effects on breast cancer cells, but there is no database where the researchers who want to design a new study on breast cancer can find these compounds all at once. This paper presents a relational database that stores the data of natural and synthetic compounds cytotoxically active on breast cancer cells. The database contains 381 cytotoxicity results and data of 159 compounds, compiled from selected 80 studies. When all this data in our database was queried, it was found out that quercetin, which is a dietary flavonoid, is the most analyzed compound, and MCF-7 cell line is the most used breast cancer cell line.

Evaluation of the chemopreventive effect of selected medicinal plants extracts via induction of the Nrf2 in a modified model of breast cancer cells: identification of bioactive lead compounds.

The cancer chemopreventive potential of various solvent extracts from six medicinal plants was evaluated by their ability to activate the transcription factor Nrf2 using AREc32 cells, which contain a luciferase gene under the control of antioxidant responsive element promoters. Nrf2 regulates the expression of many detoxification enzymes, making it an ideal target for cancer prevention. The present research revealed Zanthoxylum zanthoxyloides extracts as promising sources of cancer chemopreventive compounds. Bioassay-guided isolation of the Z. Zanthoxyloides methanol extract resulted in the isolation of N-methylatanine, N-methylplatydesminecation, sesamin and skimmianine. Among these compounds, skimmianine was identified as the most active compound, causing a 2.8-fold increase in luciferase activity. Skimmianine and other related quinolone alkaloids could represent an appropriate starting scaffold for the development of new chemopreventive cancer drugs.

Streptomyces sp. MUM256: A Source for Apoptosis Inducing and Cell Cycle-Arresting Bioactive Compounds against Colon Cancer Cells.

New and effective anticancer compounds are much needed as the incidence of cancer continues to rise. Microorganisms from a variety of environments are promising sources of new drugs; Streptomyces sp. MUM256, which was isolated from mangrove soil in Malaysia as part of our ongoing efforts to study mangrove resources, was shown to produce bioactive metabolites with chemopreventive potential. This present study is a continuation of our previous efforts and aimed to investigate the underlying mechanisms of the ethyl acetate fraction of MUM256 crude extract (MUM256 EA) in inhibiting the proliferation of HCT116 cells. Our data showed that MUM256 EA reduced proliferation of HCT116 cells via induction of cell-cycle arrest. Molecular studies revealed that MUM256 EA regulated the expression level of several important cell-cycle regulatory proteins. The results also demonstrated that MUM256 EA induced apoptosis in HCT116 cells mediated through the intrinsic pathway. Gas chromatography-mass spectrometry (GC-MS) analysis detected several chemical compounds present in MUM256 EA, including cyclic dipeptides which previous literature has reported to demonstrate various pharmacological properties. The cyclic dipeptides were further shown to inhibit HCT116 cells while exerting little to no toxicity on normal colon cells in this study. Taken together, the findings of this project highlight the important role of exploring the mangrove microorganisms as a bioresource which hold tremendous promise for the development of chemopreventive drugs against colorectal cancer.

Streptomyces monashensis sp. nov., a novel mangrove soil actinobacterium from East Malaysia with antioxidative potential

A new Streptomyces species discovered from Sarawak mangrove soil is described, with the proposed name – Streptomyces monashensis sp. nov. (strain MUSC 1JT). Taxonomy status of MUSC 1JT was determined via polyphasic approach. Phylogenetic and chemotaxonomic properties of strain MUSC 1JT were in accordance with those known for genus Streptomyces. Based on phylogenetic analyses, the strains closely related to MUSC 1JT were Streptomyces corchorusii DSM 40340T (98.7%), Streptomyces olivaceoviridis NBRC 13066T (98.7%), Streptomyces canarius NBRC 13431T (98.6%) and Streptomyces coacervatus AS-0823T (98.4%). Outcomes of DNA–DNA relatedness between strain MUSC 1JT and its closely related type strains covered from 19.7 ± 2.8% to 49.1 ± 4.3%. Strain MUSC 1JT has genome size of 10,254,857 bp with DNA G + C content of 71 mol%. MUSC 1JT extract exhibited strong antioxidative activity up to 83.80 ± 4.80% in the SOD assay, with significant cytotoxic effect against colon cancer cell lines HCT-116 and SW480. Streptomyces monashensis MUSC 1JT (=DSM 103626T = MCCC 1K03219T) could potentially be a producer of novel bioactive metabolites; hence discovery of this new species may be highly significant to the biopharmaceutical industry as it could lead to development of new and useful chemo-preventive drugs.

Bioactivity and modulatory functions of Napoleona vogelii on oxidative stress-induced micronuclei and apoptotic biomarkers in mice.

Napoleona vogelii is used in traditional medicine for the management of pain, inflammatory conditions and cancer. This study was conducted to investigate the modulatory mechanisms of methanol stem bark extract of N. vogelii on induction of micronuclei, apoptotic biomarkers and in vivo antioxidant enzymes in mice. Forty male albino mice were randomly divided into eight groups (n = 5) and were administered distilled water (DW, 5 mL/kg) as negative control, 100, 200 or 400 mg/kg of the extract respectively for 28 days before the injection of cyclophosphamide (CP, 40 mg/kg) i.p. on the 28th day. The remaining groups were administered 100, 200 or 400 mg/kg of the extract only for 28 days. Twenty four hours after injection of CP or administration of the last dose of extract, animals were euthanized by cervical dislocation and blood samples collected for determination of in vivo antioxidants, the spleen harvested for immunohistochemical expression of NFκB, Bcl-2, Bax and p53. Bone marrow smears were also made for the micronucleus assay. Treatment with the extract resulted in a significant (p < 0.0001) reduction in frequency of micronucleated polychromatic erythrocytes (MNPCEs) compared to CP exposed control conferring protection of 75.09, 94.74 and 96.84% at 100, 200 or 400 mg/kg respectively. In extract and CP exposed animals, there were significant (p < 0.05) increases in GSH, GST and SOD with a corresponding significant (p < 0.05) reduction in MDA. In addition, the extract significantly downregulated cytoplasmic levels of NFκB and Bcl-2 and upregulated Bax and p53. These findings demonstrate that N. vogelli may serve as an interesting lead for chemo-preventive drug development.

Combinatorial effect of zoledronic acid and irradiation on the prevention of DMBA-induced precancerogenic changes in the mammary tissues of rats.

At present, the rates of breast cancer are continuously increasing, with over a million new cases being diagnosed worldwide each year. Hence, the development of new breast cancer chemopreventive drugs with acceptable efficacy and toxicity that are suitable for use for a protracted period of time is urgently needed. The present study investigated the potential preventive effects of zoledronic acid [ZOL] and radiotherapy [RT], both alone and in combination, on precancerogenic changes on the breast tissues of females. Wistar rats were treated with 7,12-dimethylbenz [a] anthracene [DMBA] at the acute phase. Fifty female rats were divided into seven groups: Control group [I]; ZOL, group [II]; RT, group [III]; DMBA, group [IV]; DMBA + RT, group [V]; DMBA + ZOL, group [VI]; and DMBA + ZOL + RT, group [VII]. The treatment of DMBA-exposed rats with ZOL and RT, both alone and in combination, successfully upregulates the transcriptional levels of Bax, caspase-3, caspase-9, p21, and BRCA 1 in mammary tissues, which may account for the elevated apoptotic activities observed and the eventual inhibition of tumor growth. The administration of RT and ZOL both alone and in combination was found to be effective for inhibiting the DMBA-induced precancerogenic changes on breast tissues and modulating the expression of apoptosis-associated proteins in the acute phase. The combination of RT and ZOL was more effective than either agent alone. Our results suggest that the administration of ZOL and irradiation in combination can offer maximal protection against DMBA-induced mammary precancerogenic changes.

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

abstractBreast 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.

Biomarkers in phase I-II chemoprevention trials: lessons from the NCI experience.

Early phase clinical trials are an essential component of chemopreventive drug development to identify signals of drug efficacy that can subsequently be explored definitively in phase III trials. Whereas phase I trials focus on safety and identification of optimal dose and schedule for cancer prevention, phase II trials focus on intermediate endpoints that are variably related to cancer development. The United States National Cancer Institute supports a programme devoted to early phase cancer prevention clinical trials. The experience, along with the benefits and limitations of the range of biomarker endpoints used in these studies, are reviewed here.

Natural compound-derived epigenetic regulators targeting epigenetic readers, writers and erasers.

Post-translational modifications can affect gene expression in a long-term manner without changes in the primary nucleotide sequence of the DNA. These epigenetic alterations involve dynamic processes that occur in histones, chromatin-associated proteins and DNA. In response to environmental stimuli, abnormal epigenetic alterations cause disorders in the cell cycle, apoptosis and other cellular processes and thus contribute to the incidence of diverse diseases, including cancers. In this review, we will summarize recent studies focusing on certain epigenetic readers, writers, and erasers associated with cancer development and how newly discovered natural compounds and their derivatives could interact with these targets. These advances provide insights into epigenetic alterations in cancers and the potential utility of these alterations as therapeutic targets for the future development of chemopreventive and chemotherapeutic drugs.

Abstract 4806: Characterizing the genomic landscape of premalignant colorectal polyps using next-generation sequencing

Abstract Adenomatous polyps are the premalignant lesions that precede the development of colorectal cancers (CRC). The normal mucosa-adenoma-carcinoma sequence was originally described more than 2 decades ago; however, no comprehensive annotation of the genomic landscape of polyps has been reported to date. Familial Adenomatous Polyposis (FAP) is a mendelian disorder caused by germline mutations in the APC gene, has an autosomal dominant pattern of inheritance and is characterized by the development of adenomas in the entire intestine, thus conferring patients with a life-time risk for CRC development of 100%. Patients diagnosed with hereditary polyposis syndromes such as FAP represents the perfect model to acquire tissue samples from polyps, at-risk normal mucosa and germline allowing this type of high-throughput studies. We have performed whole exome sequencing in paired polyps and germline blood samples of 12 individuals with FAP (25 polyps and 12 blood samples) using the Illumina HiSeq 2000 platform. Using standard bioinformatics pipelines, we have identified a total of 1064 functional mutations (somatic mutations and indels) that we have classified using a 5-tier system based on functional predictions generated by several in silico tools. We have used hapLOH to ascertain for genomic imbalances from exome data and identified 26 events. Validation was performed using Sanger sequencing in a set of the identified events confirming 90% of the somatic mutations and 50% of the indels. Allelic imbalances in 5q were partially confirmed using microsatellite analysis. APC, KRAS, FBXW7, TCFL2 and ARID1A were among the 16 genes found to be recurrently mutated. Pathway enrichment analysis of the mutated gene list revealed deregulation of the Wnt, MAPK kinase and ERBB pathways, thus indicating potential avenues for chemoprevention drug development. Moreover, we assessed and compared the genomic characteristics such as the rate of transitions/transversion, mutational rate [mutations/Megabase (Mb)] and genomic imbalances with stage I CRC from the The Cancer Genome Atlas in order to understand better the carcinogenic process in the colonic epithelium at the genomic level. The signature profile of transition/transversions displayed by polyps showed abundance of C&amp;gt;T (followed by T&amp;gt;C changes) and was very similar to stage I non-hypermutator CRCs. In contrast, the mutational rate was lower in polyps (1.75 vs 3.95 mutations/Mb) and the pattern of genomic imbalances shared some events with stage I CRCs (loss of 5q and events in chromosome 7) but there were notable events seen only in the stage I CRCs most likely involved with further steps in the carcinogenesis process (loss of 18q and 17p). In conclusion, genomic assessment of premalignant colonic polyps revealed mutational patterns that are similar to stage I CRC and pointed to deregulated pathways that are potential candidates for biomarker and chemoprevention drug development. Citation Format: Ester Borras, Anthony San Lucas, Kyle Chang, Gita Bhatia, Hong Wu, Jerry Fowler, Y. Nancy You, Patrick M. Lynch, Melissa W. Taggart, Ernest T. Hawk, Gabriel Capella, Paul Scheet, Eduardo Vilar. Characterizing the genomic landscape of premalignant colorectal polyps using next-generation sequencing. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4806. doi:10.1158/1538-7445.AM2015-4806

Zerumbone attenuates TGF-β1-mediated epithelial–mesenchymal transition via upregulated E-cadherin expression and downregulated Smad2 signalling pathways in non-small cell lung cancer (A549) cells

Zerumbone, a sesquiterpene compound of edible ginger (Zingiber zerumbet), has been tested for its anti-EMT and anti-metastatic properties in TGF-β1-stimulated human lung cancer (A549) cells. Zerumbone (10/20 µM) treatment prior to TGF-β1-stimulation reversed the adverse morphological changes (fibroblastic-to-epithelial phenotype) and up-regulated the E-cadherin expression against TGF-β1-induced down-regulation. Immunofluorescence and luciferase activity data confirmed the up-regulated E-cadherin expression and transcriptional activity by zerumbone under TGF-β1-stimulation. Further evidence showed that zerumbone decreased TGF-β1-mediated phosphorylation and transcriptional activity of Smad2, but not Smad3. These results revealed that zerumbone inhibits the TGF-β-induced EMT via up-regulation of E-cadherin and down-regulation of Smad2 signalling pathways. Findings from wound-healing, invasion and colony formation experiments proved that zerumbone inhibits TGF-β1-mediated (metastatic) migration, invasion and anchorage-independent growth. Besides, zerumbone alone is capable of inducing autophagy and apoptosis in A549 cells. These results conclude that anti-EMT and anti-metastatic activities of zerumbone may contribute to the development of food-based chemopreventive drugs for non-small cell lung cancer treatment.

ANTIMUTAGENIC AND ANTIOXIDANT POTENTIAL OF AQUEOUS AND ACIDIFIED METHANOL EXTRACTS FROM CITRUS LIMONUM FRUIT RESIDUES

Aqueous and acidified methanol extracts from C. limonum fruit residues (CLFR) were evaluated for their total phenolic contents, antioxidant and antimutagenic activities. Total phenolic contents (TPC) of aqueous (30% and 70%) and acidified (0.5 N and 1.0 N) methanol extracts from CLFR were estimated by Folin- Ciocalteu reagent method whereas in-vitro antioxidant activity was assessed calorimetrically by measuring DPPHscavenging capacity and inhibition of linoleic acid peroxidation. Anti-mutagenic potential of the extracts was appraised by Ames bacterial reverse mutation test. TPC, DPPH° scavenging capacity and inhibition of linoleic acid peroxidation were varied from 27.75-126.35 mg gallic acid equivalent (GAE)/g DW, 46-91%, and 34-83%, respectively. All the tested extracts of CLFR noticeably hunted mutagens (16.47-55.69 %) whereas none of these caused mutagenesis. Overall, acidified methanol extracts from CLFR exhibited higher extraction yields, TPC, inhibition of peroxidation and DPPH radical scavenging activity among others indicating a significant ( p<0.05) variation of these attributes in relation to residue samples and extraction media. The results support that CLFR (peel and pulp biomass) being a rich source of phenolic antimutagens, can be explored as a potential candidate for the development of natural chemo-preventive drugs and nutracueticals. . Due to presence of pharmaceutically important compounds, especially phenolics, citrus can be a potential source of ingredients for the development of chemotheruapic drugs and nutracueuticals but extraction of such bioactive compounds due to their structural complexity is a challenging task. In our recent study, we observed that aqueous methanol was a good choice for the extraction of citrus fruit phenolics but the recovery rates was not promising 11 . The reason might be the presence of covalent linkage between phenolics (bound phenolics) and cell wall constituents. Conventionally, organic solvents such as methanol and ethanol are known to be efficient for the extraction of free phenolics (entrapped) but these solvents are often unable to extract and liberate citrus bound phenolics (more than 20 % phenolics are in bound form) from the well-organized cellulosic cell wall structure further fortified by lignin and in certain cases shielded by pectin 10 . During the present study, therefore, a simple acid hydrolysis based process was applied to facilitate the liberation of bound phenolics from citrus fruit residues (peel and pulp biomass) during aqueous methanol extraction. Moreover, the extracts produced by different concentrations of acidified methanol were evaluated for their phenolic contents as well as antioxidant and antimutagenic activities using in-vitro assays.

Cytotoxic effects of Euterpe oleracea Mart. in malignant cell lines.

BackgroundEuterpe oleracea Mart., a plant from the Amazon region, is commonly known as açaí or juçara; it has high nutritional value and elevated levels of lipids, proteins, and minerals. Açaí is an abundant and much consumed fruit by the Amazon local population, and studies have demonstrated that it is rich in phytochemicals with antioxidant, anti-inflammatory, and anticancer activities. Therefore, the aim of this study was to test this plant for anticancer activity in different human malignant cell lines.MethodsCell lines derived from breast and colorectal adenocarcinomas were treated with 10, 20, and 40 μg/mL of bark, seed, and total açaí fruit hydroalcoholic extracts for 24 and 48 h. After treatment, cell viability was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, and cell morphological features were observed by light and transmission electron microscopy. The type of cell death was also evaluated. The data were analyzed statistically by one-way analysis of variance (ANOVA), followed by Dunnett’s or Tukey’s post hoc tests, as appropriate.ResultsWe observed that of all the cell lines tested, MCF-7 was the only line that responded to açaí treatment. The extracts caused significant reduction (p < 0.01) in cell viability and altered cell morphological features by inducing the appearance of autophagic vacuoles, as observed by transmission electron microscopy. Furthermore, increased expression of LC3BII, a protein marker of autophagosome formation, was observed by western blotting. Caspase Glo™ assays and morphologic observations by DAPI nuclear staining and transmission electron microscopy did not indicate any apoptotic events.ConclusionsThe present study demonstrated that açaí possesses antitumorigenic potential in the MCF-7 cell line. Further studies are needed to identify the compound (s) responsible for this cytotoxic activity and the molecular target in the cell. This discovery of the anticancer potential of açaí may help in the development of chemopreventive drugs and may have therapeutic effects in the treatment of breast cancer.

Molecular targets and chemoprevention drug development in hereditary colorectal cancer syndromes

Molecular targets and chemoprevention drug development in hereditary colorectal cancer syndromes

Early Detection and Prevention of Pancreatic Cancer: Use of Genetically Engineered Mouse Models and advanced Imaging Technologies

Lack of early detection and effective interventions are major factors contributing to the poor prognosis and dismal survival rates of pancreatic cancer patients for more than sixty years. Detection of pancreatic cancer at an early stage might permit life-saving intervention. Clinical and preclinical diagnosis and evaluation of pancreatic cancers involve several imaging technologies including magnetic resonance imaging (MRI), Positron emission tomography (PET), Computed tomography (CT), Ultrasound (US), bioluminescent imaging and single photon emission computed tomography (SPECT). The advent of genetically engineered animal models that recapitulate the cellular and molecular pathology of human pancreatic intraepithelial neoplasia (PanINs) and pancreatic ductal adenocarcinoma (PDAC) has not yet yielded translational implications. Although the use of tumor xenografts to predict drug efficacy in patients has been disappointing, use of novel transgenic mice models should permit improved early detection and development of drug regimens through integration of appropriate imaging modalities. This review will consider issues that are unique to working with transgenic mouse models, such as the biology of genetically engineered mouse (GEM) models, stage- tumor-specific detection using imaging technologies, use of monoclonal antibodies, nanoparticles, and biomarkers, and development of chemopreventive and chemotherapeutic drugs for PDAC. These issues will be considered in the context of recently developed preclinical models of pancreatic cancer.

Apoptosis-Induced Cell Death due to Oleanolic Acid in HaCaT Keratinocyte Cells -a Proof-of-Principle Approach for Chemopreventive Drug Development

Oleanolic acid (OA) is a naturally occurring triterpenoid in food materials and is a component of the leaves and roots of Olea europaea, Viscum album L., Aralia chinensis L. and more than 120 other plant species. There are several reports validating its antitumor activity against different cancer cells apart from its hepatoprotective activity. However, antitumor activity against skin cancer has not been studied well thus far. Hence the present study of effects of OA against HaCaT (immortalized keratinocyte) cells--a cell-based epithelial model system for toxicity/ethnopharmacology-based studies--was conducted. Radical scavenging activity (DPPH·) and FRAP were determined spectrophotometrically. Proliferation was assessed by XTT assay at 24, 48 and 72 hrs with exposure to various concentrations (12.5-200 μM) of OA. Apoptotic induction potential of OA was demonstrated using a cellular DNA fragmentation ELISA method. Morphological studies were also carried out to elucidate its antitumor potential. The results revealed that OA induces apoptosis by altering cellular morphology as well as DNA integrity in HaCaT cells in a dose-dependent manner, with comparatively low cytotoxicity. The moderate toxicity observed in HaCaT cells, with induction of apoptosis, possibly suggests greater involvement of programmed-cell death-mediated mechanisms. We conclude that OA has relatively low toxicity and has the potential to induce apoptosis in HaCaT cells and hence provides a substantial and sound scientific basis for further validation studies.

Abstract A56: Induction of spermine oxidase by enterotoxigenic Bacteroides fragilis contributes to tumorigenesis in a model of colitis-associated colorectal cancer

Abstract It is estimated that the etiology of 20-30% of epithelial cancers is directly associated with inflammation, though the molecular events linking inflammation and the necessary carcinogenic mutations remain to be clarified. In the context of gastrointestinal disease, the bacterial pathogens Helicobacter pylori and enterotoxigenic Bacteroides fragilis (ETBF) are significant sources of chronic inflammation and have been implicated as risk factors for the development of gastric and colorectal cancer, respectively. We have previously demonstrated that H. pylori and the cytokine tumor necrosis factor-α (TNF-α) rapidly induce spermine oxidase (SMO), resulting in increased cellular reactive oxygen species (ROS) and DNA damage, in gastric and lung epithelial cells. In addition, tissue microarray studies revealed that increased SMO expression was associated with prostatic intraepithelial neoplasia and prostate cancer lesions and that benign prostate epithelial tissue from men with these diseases exhibits higher SMO expression than normal controls. We now demonstrate that purified B. fragilis toxin (BFT) upregulates SMO in HT29/c1 and T84 colonic epithelial cells, resulting in SMO-dependent induction of γ-H2A.x, a marker of DNA damage. Further, ETBF-induced colitis in wild-type or APC+/− Min C57Bl/6 mice is associated with increased SMO expression. Inhibition of SMO activity by MDL 72,527 in vivo (20 mg/kg i.p. 3 days per week) significantly reduces ETBF-induced chronic inflammation, proliferation, and induction of Th17-associated cytokines. Most importantly, in Min mice, treatment with the SMO inhibitor reduces ETBF-induced colon tumorigenesis by 69% (p&amp;lt;.001). Our studies suggest that SMO is a novel target for chemopreventive or chemotherapeutic drug development. Citation Information: Cancer Prev Res 2010;3(12 Suppl):A56.

Impact of saffron as an anti-cancer and anti-tumor herb.

Cancer continues to represent the largest cause of mortality in the world and claims over 6 million lives each year. An extremely promising strategy for cancer prevention today is chemoprevention, which is defined as the use of synthetic or natural agents (alone or in combination) to block the development of cancer in human beings. Plants, vegetables, herbs and spices used in folk and traditional medicine have been accepted currently as one of the main sources of cancer chemopreventive drug discovery and development. This review gives an overview from one of this herbs and spices that is saffron. The chemical composition of saffron has attracted the interest of several research groups during the last decades, and among the estimated more than 150 volatile and several nonvolatile compounds of saffron, approximately 40 – 50 constituents have already been identified. Oral administration of saffron extract inhibited the growth of mouse tumors that were derived from three different kinds of cancer cells and significantly increased the life spans of treated tumor-bearing mice. Key words: Chemoprevention, volatile, tumor-bearing.

Abstract A32: Identification of biomarkers in normal human breast cells regulated by the cancer preventive rexinoid LG100268

Abstract Background: Drugs targeting estrogen signaling or production have become useful in preventing estrogen receptor-positive breast cancers, but not estrogen receptor-negative (ER-negative) breast cancers. Our laboratory has demonstrated that rexinoids prevent ER-negative mammary tumors in transgenic mice by 90%. However, since these agents are not 100% effective, we are investigating the mechanism by which rexinoids prevent cancer to develop more efficacious prevention strategies. We hypothesized that by identifying molecules regulated by the rexinoid LG100268, future chemopreventive agents could be developed to target these molecules alone or in combination with rexinoids to totally prevent breast cancer development. To investigate this hypothesis we utilized an Affymetrix genome array to identify biomarkers regulated by LG100268. Methods: Cell counts were used to confirm rexinoid-induced growth suppression in normal human mammary epithelial cells (HMECs). TUNEL analysis was conducted to determine whether the growth suppression was a result of induction of apoptosis. We conducted Affymetrix analysis using 10ug total RNA from HMECs treated with 0.1% vehicle or 1uM LG100268 for 1 hour or 24 hours. cRNA was hybridized with the GeneChip® Expression Analysis Array (U133) from Affymetrix. Results were analyzed using Microarray Suite 5.0 (Affymetrix). Genes to be considered for further confirmation had a fold change of &amp;gt; 1.5 or &amp;lt; 0.8 (p &amp;lt; 0.05) for up- or down-regulated genes, respectively. Geneontology analysis identified candidate genes involved in proliferation, cell cycle and metabolism as genes to consider for further analysis. Quantitative RT-PCR (qRT-PCR) and standard western blot techniques were used to confirm regulation of selected up- and down-regulated genes at the mRNA and protein levels, respectively. Results: Cell count analysis confirmed that LGD1069 greatly suppressed growth of HMEC cells, while LG100268 slightly suppressed HMEC growth. TUNEL analysis indicated that neither rexinoid treatment induced a significant amount of apoptosis in HMEC cells, indicating that the induction of growth suppression was not a result of apoptosis. A full list of genes up- and down-regulated by LGD100268 will be presented. Of those genes selected for further study, qRT-PCR analysis confirmed that LG100268 up-regulated stanniocalcin 1 (STC1), carbonic anhydrase IX (CA9), angiopoietin-like 4 (ANGPTL4), transglutaminase 2 (TGM2), and acyl-CoA synthetase long-chain family member 3 (ACSL3). Confirmed down-regulated genes at the mRNA level included cyclin B1 (CCNB1). Additional validation studies are ongoing. These up- and down-regulated genes may be useful targets for chemopreventive drug development. Conclusions: These experiments identified a list of biomarkers that are regulated by LG100268. Such rexinoid-regulated molecules represent possible targets for breast cancer preventative therapy, alone or in combination with rexinoids. Support: NCI R01 CA78480 (PHB and IPU), and NIH/NCI T32 CA90221 (JMR). Citation Information: Cancer Prev Res 2010;3(1 Suppl):A32.