zerumbone and Colonic-Neoplasms

Chronic inflammation has been linked to colitis-associated colorectal cancer in humans. The human symbiont enterotoxigenic Bacteroides fragilis (ETBF), a pro-carcinogenic bacterium, has the potential to initiate and/or promote colorectal cancer. Antibiotic treatment of ETBF has shown promise in decreasing colonic polyp formation in murine models of colon cancer. However, there are no reported natural products that have shown efficacy in decreasing polyp burden. In this study, we investigated the chemopreventive effects of oral administration of zerumbone in ETBF-colonized mice with azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced tumorigenesis. Zerumbone significantly reduced the severity of disease activity index (DAI) scores as well as several parameters of colonic inflammation (i.e., colon weight, colon length, cecum weight and spleen weight). In addition, inflammation of the colon and cecum as well as hyperplasia was reduced. Zerumbone treatment significantly inhibited colonic polyp numbers and prevented macroadenoma progression. Taken together, these findings suggest that oral treatment with zerumbone inhibited ETBF-promoted colon carcinogenesis in mice indicating that zerumbone could be employed as a promising protective agent against ETBF-mediated colorectal cancer.

Topics: Administration, Oral; Animals; Azoxymethane; Bacteroides fragilis; Body Weight; Carcinogenesis; Colitis; Colonic Neoplasms; Dextran Sulfate; Female; Mice; Mice, Inbred BALB C; Protective Agents; Sesquiterpenes; Severity of Illness Index

Death receptor 5 (DR5) is a death domain-containing transmembrane receptor that triggers cell death upon binding to its ligand, TNF-related apoptosis-inducing ligand (TRAIL), and a combination of TRAIL and agents that increase the expression of DR5 is expected to be a novel anticancer therapy. In this report, we demonstrate that the stress response gene ATF3 is required for endoplasmic reticulum stress-mediated DR5 induction upon zerumbone (ZER) and celecoxib (CCB) in human p53-deficient colorectal cancer cells. Both agents activated PERK-eIF2α kinases and induced the expression of activating transcription factor 4 (ATF4)-CCAAT enhancer-binding protein (C/EBP) homologous protein, which were remarkably suppressed by reactive oxygen species scavengers. In the absence of ATF3, the induction of DR5 mRNA and protein was abrogated significantly, and this was associated with reduced cell death by cotreatment of TRAIL with ZER or CCB. By contrast, exogenous expression of ATF3 caused a more rapid and elevated expression of DR5, resulting in enhanced sensitivity to apoptotic cell death by TRAIL/ZER or TRAIL/CCB. A reporter assay demonstrated that at least two ATF/cAMP response element motifs as well as C/EBP homologous protein motif at the proximal region of the human DR5 gene promoter were required for ZER-induced DR5 gene transcription. Taken together, our results provide novel insights into the role of ATF3 as an essential transcription factor for p53-independent DR5 induction upon both ZER and CCB treatment, and this may be a useful biomarker for TRAIL-based anticancer therapy.

Topics: Activating Transcription Factor 3; Apoptosis; Base Sequence; Celecoxib; Cell Line, Tumor; Colonic Neoplasms; DNA Primers; Endoplasmic Reticulum; Humans; Promoter Regions, Genetic; Pyrazoles; Receptors, TNF-Related Apoptosis-Inducing Ligand; Reverse Transcriptase Polymerase Chain Reaction; Sesquiterpenes; Sulfonamides; TNF-Related Apoptosis-Inducing Ligand

Zerumbone (ZER), present in subtropical ginger Zingiber zerumbet Smith, possesses anti-growth and anti-inflammatory properties in several human cancer cell lines. ZER also down-regulates the cyclooxygenase-2 and inducible nitric oxide synthase expression via modulation of nuclear factor (NF)-kappaB activation in cell culture systems. These findings led us to investigate whether ZER is able to inhibit carcinogenesis in the colon and lung, using 2 different preclinical mouse models. In Exp. 1, a total of 85 male ICR mice were initiated using a single intraperitoneal (i.p.) injection with azoxymethane (AOM, 10 mg/kg bw) and promoted by 1.5% dextran sulfate sodium (DSS) in drinking water for 7 days for rapid induction of colonic neoplasms. Animals were then fed the diet containing 100, 250 or 500 ppm ZER for 17 weeks. In Exp. 2, a total of 50 female A/J mice were given a single i.p. injection of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (10 micromol/mouse) to induce lung proliferative lesions. They were then fed the diet mixed with 100, 250 or 500 ppm ZER for 21 weeks. At the termination of the experiments (wk 20 of Exp. 1 and wk 22 of Exp. 2), all animals were subjected to complete necropsy examination to determine the pathological lesions in both tissues. Oral administration of ZER at 100, 250 and 500 ppm significantly inhibited the multiplicity of colonic adenocarcinomas. The treatment also suppressed colonic inflammation. In the lung carcinogenesis, ZER feeding at 250 and 500 ppm significantly inhibited the multiplicity of lung adenomas in a dose-dependent manner. Feeding with ZER resulted in inhibition of proliferation, induction of apoptosis, and suppression of NFkappaB and heme oxygenase (HO)-1 expression in tumors developed in both tissues. Our findings suggest that dietary administration of ZER effectively suppresses mouse colon and lung carcinogenesis through multiple modulatory mechanisms of growth, apoptosis, inflammation and expression of NFkappaB and HO-1 that are involved in carcinogenesis in the colon and lung.

Topics: Animals; Anticarcinogenic Agents; Cell Line, Tumor; Colonic Neoplasms; Female; Gene Expression Regulation, Neoplastic; Humans; Lung Neoplasms; Male; Mice; Mice, Inbred ICR; NF-kappa B; Sesquiterpenes; Zingiber officinale

Identification of the active component and mechanisms of action of traditional medicines is highly desirable. We investigated whether zerumbone, a sesquiterpene from tropical ginger, can enhance the anticancer effects of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). We found that zerumbone potentiated TRAIL-induced apoptosis in human HCT116 colon cancer cells and that this correlated with the up-regulation of TRAIL death receptor (DR) 4 and DR5. Induction of DRs occurred at the transcriptional level, and this induction was not cell-type specific, as its expression was also up-regulated in prostate, kidney, breast, and pancreatic cancer cell lines. Deletion of DR5 or DR4 by small interfering RNA significantly reduced the apoptosis induced by TRAIL and zerumbone. In addition to up-regulating DRs, zerumbone also significantly down-regulated the expression of cFLIP but not that of other antiapoptotic proteins. The induction of both DRs by zerumbone was abolished by glutathione and N-acetylcysteine (NAC), and this correlated with decreased TRAIL-induced apoptosis, suggesting a critical role of reactive oxygen species. Inhibition of extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinase but not of Jun NH(2)-terminal kinase abolished the effect of zerumbone on DR induction. Zerumbone also induced the p53 tumor suppressor gene but was found to be optional for DR induction or for enhancement of TRAIL-induced apoptosis. Both bax and p21, however, were required for zerumbone to stimulate TRAIL-induced apoptosis. Overall, our results show that zerumbone can potentiate TRAIL-induced apoptosis through the reactive oxygen species-mediated activation of extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinase leading to DR4 and DR5 induction and resulting in enhancement of the anticancer effects of TRAIL.

Topics: Apoptosis; Colonic Neoplasms; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Drug Synergism; Gene Expression Regulation, Neoplastic; HCT116 Cells; HT29 Cells; Humans; Reactive Oxygen Species; Receptors, Death Domain; RNA, Small Interfering; Sesquiterpenes; TNF-Related Apoptosis-Inducing Ligand; Tumor Cells, Cultured

Zerumbone, a sesquiterpene occurring in zingiberaceous plants in Southeast Asian countries, has been shown to have anti-inflammatory effects in several independent experimental studies. We examined its effect on the expression of proinflammatory genes in human colon adenocarcinoma cell lines, Caco-2, Colo320DM, and HT-29, using reverse transcription-polymerase chain reaction (RT-PCR) assays. Surprisingly, zerumbone markedly induced the expression of interleukin (IL)-1alpha, IL-1beta, IL-6, and tumor necrosis factor (TNF)-alpha in each cell line in concentration- and time-dependent manners. Results of a previous pharmacological approach using specific inhibitors of mitogen-activated protein kinases (MAPKs) suggested that the activation of both c-Jun N-terminal kinase and extracellular signal-regulated protein kinase, however, not that of p38 MAPK, may be involved in zerumbone-induced IL-1beta expression pathways in Caco-2 cells. The present results imply that zerumbone increases the production of proinflammatory cytokines in cancerous tissues in the colon and that this biochemical property may cause side-effects.

Topics: Adenocarcinoma; Anti-Inflammatory Agents, Non-Steroidal; Cell Line, Tumor; Colonic Neoplasms; Cytokines; Gene Expression Regulation; Humans; Inflammation; Phytotherapy; Plant Extracts; Reverse Transcriptase Polymerase Chain Reaction; Sesquiterpenes

The anticancer properties of zerumbone (2,6,9 humulatriene-8-one, a sesquiterpenoid) from Zingiber aromaticum were compared with those of curcumin from Curcuma longa in an in vitro MTT tetrazolium salt assay using HT-29, CaCo-2, and MCF-7 cancer cells and in an azoxymethane (AOM)-induced animal model of colon cancer using aberrant crypt foci (ACFs) as a preneoplastic marker. The IC50 of zerumbone was approximately 10 mM and that of curcumin was 25 mM. Cell cycle arrest in HT-29 cells was observed at G0/G1 for 10 and 12.5 mM and G2/M for 25 mM after 24 h at concentrations of 10-25 mM of zerumbone, and a concentration-dependent increase in apoptosis (2-6% of viable cells) was observed after 48 h using the same concentration range. Male Sprague-Dawley rats were fed extracts in an AIN diet prepared from the equivalent of 4% by weight of dried rhizomes of Z. aromaticum and C. longa. ACFs were induced by two doses (15 mg/kg body weight) subcutaneously of AOM 1 wk apart, the rats were killed 10 wk later, and the ACFs were assessed in the colon. Total ACFs were significantly reduced by Z. aromaticum extract (down 21%, P < 0.05) relative to control, the effect being most evident with large ACFs (>3 aberrant crypts per focus). Similar reductions were observed with 4% C. longa extract in the diet (down 24%, P < 0.01) and with 2,000 ppm curcumin, the effect being particularly evident with large ACFs. The concentration of zerumbone in the Z. aromaticum extract diet was assayed at 300 ppm and of curcumin in the C. longa extract diet was also 300 ppm, i.e., the extract of C. longa was as effective at one-seventh the concentration of curcumin as the positive control. Zerumbone is effective as an anticancer agent, possibly by its apoptosis-inducing and antiproliferative influences. This latter possibility is currently being investigated.

Topics: Animals; Anticarcinogenic Agents; Apoptosis; Cell Cycle; Cell Division; Colonic Neoplasms; Curcumin; Dose-Response Relationship, Drug; Humans; Inhibitory Concentration 50; Male; Plant Extracts; Rats; Rats, Sprague-Dawley; Sesquiterpenes; Time Factors; Tumor Cells, Cultured; Zingiberaceae

A recent report shows that zerumbone (ZER) inhibits the proliferation of, and induces apoptosis in, colon cancer cells. We suggest a mechanism for these phenomena, based on our recently proposed redox model of cell proliferation which stresses the importance of intracellular redox potential E in the control of proliferation of normal and cancer cells.

Topics: Adenocarcinoma; Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Cell Cycle; Cell Division; Colonic Neoplasms; Fibroblasts; Fibrosarcoma; Glutathione; Humans; Neoplastic Stem Cells; Oxidation-Reduction; Phosphorylation; Phytotherapy; Protein Processing, Post-Translational; Retinoblastoma Protein; Sesquiterpenes; Structure-Activity Relationship

Zerumbone (ZER), a sesquiterpene from the edible plant Zingiber zerumbet Smith, has recently been found to suppress tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced Epstein-Barr virus activation in a potent manner. In the present study, we evaluated the anti-inflammatory and chemopreventive potentials of ZER in a variety of cell culture experiments. ZER effectively suppressed TPA-induced superoxide anion generation from both NADPH oxidase in dimethylsulfoxide-differentiated HL-60 human acute promyelocytic leukemia cells and xanthine oxidase in AS52 Chinese hamster ovary cells. The combined lipopolysaccharide- and interferon-gamma-stimulated protein expressions of inducible nitric oxide synthase and cyclooxygenase (COX)-2, together with the release of tumor necrosis factor-alpha, in RAW 264.7 mouse macrophages were also markedly diminished. These suppressive events were accompanied with a combined decrease in the medium concentrations of nitrite and prostaglandin E(2), while the expression level of COX-1 was unchanged. ZER inhibited the proliferation of human colonic adenocarcinoma cell lines (LS174T, LS180, COLO205, and COLO320DM) in a dose-dependent manner, while the growth of normal human dermal (2F0-C25) and colon (CCD-18 Co) fibroblasts was less affected. It also induced apoptosis in COLO205 cells, as detected by dysfunction of the mitochondria transmembrane, Annexin V-detected translocation of phosphatidylserine, and chromatin condensation. Intriguingly, alpha-humulene, a structural analog lacking only the carbonyl group in ZER, was virtually inactive in all experiments conducted, indicating that the alpha,beta-unsaturated carbonyl group in ZER may play some pivotal roles in interactions with unidentified target molecule(s). Taken together, our results indicate that ZER is a food phytochemical that has distinct potentials for use in anti-inflammation, chemoprevention, and chemotherapy strategies.

Topics: Adenocarcinoma; Animals; Anticarcinogenic Agents; Apoptosis; Cell Division; Colonic Neoplasms; Cyclooxygenase 2; Free Radicals; Humans; Isoenzymes; Membrane Proteins; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Prostaglandin-Endoperoxide Synthases; Sesquiterpenes; Superoxides; Tetradecanoylphorbol Acetate; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha

The modifying effects of dietary feeding of zerumbone isolated from Zingiber zerumbet on the development of azoxymethane (AOM)-induced colonic aberrant crypt foci (ACF) were investigated in male F344 rats. Expression of cyclooxygenase (COX)-2 in colonic mucosa exposed to AOM and/or zerumbone was also assayed. In addition, we assessed the effects of zerumbone on cell proliferation activity of crypts by counting silver-stained nucleolar organizer regions protein (AgNORs) in colonic cryptal cell nuclei. To induce ACF rats were given three weekly subcutaneous injections of AOM (15 mg/kg body weight). They were also fed the experimental diet containing 0.01% or 0.05% zerumbone for 5 weeks, starting one week before the first dosing of AOM. AOM exposure produced 84+/-13 ACF/rat at the end of the study (week 5). Dietary administration of zerumbone caused reduction in the frequency of ACF: 72+/-17 (14% reduction) at a dose of 0.01% and 45+/-18 (46% reduction, p<0.001) at a dose of 0.05%. Feeding of zerumbone significantly reduced expression of COX-2 and prostaglandins in colonic mucosa. Zerumbone feeding significantly lowered the number of AgNORs in colonic crypt cell nuclei. These findings might suggest possible chemopreventive ability of zerumbone, through suppression of COX-2 expression, cell proliferating activity of colonic mucosa, and induction of phase II detoxification enzymes in the development of carcinogen-induced ACF.

Topics: Animals; Anticarcinogenic Agents; Azoxymethane; Cell Division; Colon; Colonic Neoplasms; Cyclooxygenase 2; Diet; Dinoprostone; Dose-Response Relationship, Drug; Glutathione Transferase; Intestinal Mucosa; Isoenzymes; Liver; Male; NAD(P)H Dehydrogenase (Quinone); Nucleolus Organizer Region; Precancerous Conditions; Prostaglandin D2; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Inbred F344; Sesquiterpenes; Silver Staining; Zingiberaceae