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Sample records for dmba

  1. Photochemical Reaction of 7,12-Dimethylbenz[a]anthracene (DMBA and Formation of DNA Covalent Adducts

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    Peter P. Fu

    2005-04-01

    Full Text Available DMBA, 7,12-dimethylbenz[a]anthracene, is a widely studied polycyclic aromatic hydrocarbon that has long been recognized as a probable human carcinogen. It has been found that DMBA is phototoxic in bacteria as well as in animal or human cells and photomutagenic in Salmonella typhimurium strain TA102. This article tempts to explain the photochemistry and photomutagenicity mechanism. Light irradiation converts DMBA into several photoproducts including benz[a]anthracene-7,12-dione, 7-hydroxy-12-keto-7-methylbenz[a]anthracene, 7,12-epidioxy-7,12-dihydro-DMBA, 7-hydroxymethyl-12-methylbenz[a]anthracene and 12-hydroxymethyl-7-methylbenz[a]anthracene. Structures of these photoproducts have been identified by either comparison with authentic samples or by NMR/MS. At least four other photoproducts need to be assigned. Photo-irradiation of DMBA in the presence of calf thymus DNA was similarly conducted and light-induced DMBA-DNA adducts were analyzed by 32P-postlabeling/TLC, which indicates that multiple DNA adducts were formed. This indicates that formation of DNA adducts might be the source of photomutagenicity of DMBA. Metabolites obtained from the metabolism of DMBA by rat liver microsomes were reacted with calf thymus DNA and the resulting DNA adducts were analyzed by 32P-postlabeling/TLC under identical conditions. Comparison of the DNA adduct profiles indicates that the DNA adducts formed from photo-irradiation are different from the DNA adducts formed due to the reaction of DMBA metabolites with DNA. These results suggest that photo-irradiation of DMBA can lead to genotoxicity through activation pathways different from those by microsomal metabolism of DMBA.

  2. Addition compounds of lanthanide and yttrium-perchlorates and nitrates with N,N-Dimethylbenzamide (DMBA)

    International Nuclear Information System (INIS)

    Giesbrecht, E.; Tfouni, E.; Sao Paulo Univ.

    1980-01-01

    The synthesis and physical properties of the compounds Ln(ClO 4 ) 3 .6 DMBA and Ln.(NO 3 ) 3 .3DMBA (Ln=La to Lu, except Pm, and including Y), (DMBA=N,N-dimethylbenzamide) are reported. They were characterized by elemental analysis, melting ranges, infrared spectra, electrolytic conductance measurements and X-ray diffraction powder patterns. (Author) [pt

  3. EFEK EKSTRAK SAMBILOTO (ANDROGRAPHIS PANICULATA NEES PADA EKSPRESI TELOMERASE DARI KANKER PAYUDARA TIKUS YANG DIINDUKSI DENGAN DMBA

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    Yurika Sastyarina

    2010-12-01

    Full Text Available ABSTRACT   It has been well documented that chemical carcinogen, 7.12 dimethylbenz(aanthracene (DMBA,  plays a role in the incidence and growth of mammary cancer. Present study was designed to investigate the influence of Andrographis paniculata extract on telomerase activities on DMBA induced breast cancer in the female rat Sprague Dawley strain. DMBA-induced mammary cancer is a useful model to investigate the changes of epithelial cells that occur during mammary cancer progression. Mammary cancer model was induced 10 times twice a week by oral DMBA 20 mg/kg body weight. Mammary cancer occurred in 75 % animals nine weeks after oral administration of DMBA, it was represented with nodule on the mammary gland and the increasing of mammary gland volume compare with normal control F(1.8 = 731.711; p < 0.001. This study was also designed to investigate the effect of Andrographis paniculata extract mammary carcinoma induced by DMBA. Administration of three different dose of Andrographis paniculata (100 mg/kg, 300 mg/kg and 1000 mg/kg had statistically different with mammary gland volume of DMBA treated rat F (4.17 = 92.777; p<0.05. So, Andrographis paniculata has significant effect on the treatment of DMBA-induced mammary carcinoma. The Epithelial cells were harvested on day 90 and stained with routine histology staining, hematoxylineosin, for morphological qualitative analysis, immunohistochemical examination. The lesions observed from the removed samples ranged widely from benign to malignant. The results showed that DMBA induce cell proliferation, nuclear irregularities, and numerous mitoses and induced cell necrosis. The effect of Andrographis paniculata inhibits cell proliferation and induces apoptosis in cancer cells. On immunohistochemical examination, it shows that Andrographis paniculata can stimulate of telomerase enzyme.   Key word: Andrographis paniculata, DMBA, mammary cancer, cell proliferation     ABSTRAK   Telah dilakukan

  4. Protective Effect of Piper aduncum Capsule on DMBA-induced Breast Cancer in Rats.

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    Arroyo-Acevedo, J; Chávez-Asmat, R J; Anampa-Guzmán, A; Donaires, R; Ráez-Gonzáles, José

    2015-01-01

    The possible protective effect of Piper aduncum capsule on DMBA (dimethylbenz[α]anthracene)-induced breast cancer in rats was assessed by monitoring the tumor and lung metastases incidence and recording hematological and biochemical parameters and frequency of micronuclei. Mammary carcinogenesis was induced in 36 female Holtzman rats by providing a single subcutaneous injection of DMBA. Oral administration of P. aduncum capsule lowered adenocarcinoma and lymph node metastases incidence. Pulmonary metastasis was significantly lowered (P < 0.05). Hematological indicators showed that the triglyceride level was significantly lowered (P < 0.01) and high-density lipoprotein (HDL) level was significantly increased (P < 0.01). Also, P. aduncum capsule significantly lowered the C reactive protein (CRP) level (P < 0.01) and malondialdehyde level (P < 0.05). There was a significant decrease in the frequency of DMBA-induced micronucleated polychromatic erythrocyte (P < 0.01). Considering the antitumorigenic, hypolipidemic, anti-inflammatory, antioxidant, and antigenotoxic properties of P. aduncum capsule, we conclude that it has a protective effect on DMBA-induced breast cancer in rats.

  5. Inhibition of murine splenic B lymphocyte activation following oral exposure to 7,12-dimethylbenz(a)anthracene (DMBA)

    International Nuclear Information System (INIS)

    Davis, D.P.; Burchiel, S.W.; Montano, R.M.; Seamer, L.C.

    1991-01-01

    Previous results from this laboratory have demonstrated that oral exposure of B6C3F1 mice to DMBA inhibited mitogen-stimulated lymphocyte activation in cells recovered from several lymphoid organs. These studies showed that both LPS and PHA-stimulated lymphocyte proliferation and PHA-induced Ca +2 mobilization were significantly inhibited by DMBA exposure, supporting the hypothesis that DMBA inhibits early events associated with lymphocyte activation. The purpose of the current studies was to test this hypothesis directly for B cell activation. B6C3F1 mice were treated with 0, 1.0, or 10 mg/kg/day doses of DMBA for 14 days (total cumulative doses of 0, 14, or 140 mg/kg). B lymphocyte populations were then selected on the flow cytometer by direct positive staining of spleen cells with phycoerythrin-labeled anti-Ly5 (B lymphocyte marker) antibodies. Ca +2 mobilization studies were performed using affinity-purified goat anti-mouse IgD antibodies as the stimulant and Indo-1 as the intracellular Ca +2 indicator. Cell proliferation studies were also performed using 3 H-thymidine and insoluble anti-IgD antibodies. Anti-IgD stimulated Ca +2 mobilization was significantly reduced at the 140 mg/kg dose of DMBA. A statistically significant decrease in anti-IgD stimulated B lymphocyte proliferation at the 14 mg/kg and 140 mg/kg doses of DMBA was found. These results suggest that B lymphocytes may be important targets for DMBA-mediated immunosuppression

  6. Carcinogenese quimica por DMBA (7,12-dimethylbenzanthracene em camundongos femeas BALB/c: novos fatos

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    Krishna Duro de Oliveira

    2015-06-01

    Full Text Available Polycyclic aromatic hydrocarbons are known carcinogens used in rodent experimental models. In this study, the carcinogen DMBA (7,12-dimethylbenzanthracene was administered by gavage, diluted in corn oil, to female BALB / c mice at hebdomadary doses of 1 mg per animal for 1, 3, 6 or 9 weeks. Animals were weighed and monitored weekly until death. Remaining animals were euthanized at the age of 53 weeks. At necropsy, representative fragments of neoplasms were collected and routinely processed for histopathological analysis. Of all mice that received DMBA, 68.57% developed some type of tumor. Of the 70 mice treated with various doses of DMBA, 22 (31.43% developed mammary tumors. The adenoacanthoma was the most commonly (18.75% diagnosed histological type of breast cancer. Lung (15.71%, lymphoid tissue (11.43%, stomach (7.14% and skin (2.86% were also primary sites of tumor development. One third (33.33% of the mice receiving 1 mg of DMBA developed lung cancer. Therefore, the administration of DMBA was shown to be an efficient model of carcinogenesis in mice, especially for the study of breast cancer, when using the highest dose, and lung, when using the lowest dose. Carcinogenesis models have been used for several purposes in cancer research. These results represent new facts for a classic carcinogenesis model.

  7. Synthesis, characterization and thermal decomposition of [Pd2 (C2-dmba (µ-SO4 (SO22

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    Caires Antonio Carlos Fávero

    1998-01-01

    Full Text Available The bridged sulphate complex [Pd2 (C²,dmba (µ-SO4 (SO22] has been obtained by reacting a saturated solution of SO2 in methanol and the cyclometallated compound [Pd(C²,N-dmba(µ-N3] 2; (dmba = N,N-dimethylbenzylamine, at room temperature for 24 h. Reaction product was characterized by elemental analysis, NMR comprising 13C{¹H} and ¹H nuclei and I.R. spectrum's measurements. Thermal behavior has been investigated and residual products identified by X-ray powder diffraction.

  8. Chemoprevention by Quercetin of Oral Squamous Cell Carcinoma by Suppression of the NF-κB Signaling Pathway in DMBA-treated Hamsters.

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    Zhang, Wen; Yin, Gang; Dai, Jianguo; Sun, Y U; Hoffman, Robert M; Yang, Zhijian; Fan, Yuan

    2017-08-01

    The aim of this study was to investigate the effects of the flavonoid quercetin on chemoprevention of oral squamous cell carcinoma (OSCC). The study involved molecular signaling pathways in 7,12-dimethylbenz(a) anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis. DMBA (0.5%) was painted at the right buccal pouches of hamsters for 14 weeks to induce carcinoma. DMBA-treated hamsters received simultaneous doses of quercetin. Animals without DMBA induction were used as normal controls. The incidence of OSCC and the severity of pre-malignant lesions were determined histologically. Apoptosis in the pouch tissue was determined by TUNEL staining. The mRNA and protein expression of NF-κB p50 and p65, as well as Bcl-2 and Bax genes were analyzed using RT-PCR and Western blotting, respectively. Quercetin, at various doses, significantly reduced OSCC incidence and severity of hyperplasia and dysplasia compared to the DMBA-induction-only group (p<0.01). Apoptosis was induced by quercetin treatment compared to the DMBA-induction-only group (p<0.01). mRNA and protein expression of NF-κB p50, p65 as well as Bcl-2 genes were significantly suppressed by quercetin at high doses compared to DMBA induction only (p<0.05). However, mRNA and protein expression of the Bax gene was increased by quercetin treatment at medium and high doses, compared to the DMBA-induction-only group (p<0.05). Quercetin significantly reduced body-weight loss compared to the DMBA-induction-only group (p<0.05). Quercetin reduced tumor incidence and induced apoptosis through modulation of NF-κB signaling and its target genes Bcl-2 and Bax in the DMBA-induced carcigenesis hamster model, suggesting the potential of quercetin as a candidate for OSCC chemoprevention. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  9. Identification and quantification of 1,3-dimethylbutylamine (DMBA) from Camellia sinensis tea leaves and dietary supplements

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    1, 3-Dimethylbutylamine (DMBA), is a CNS stimulant which has recently been identified in multiple dietary supplements and sometimes labeled as a natural constituent of Pouchung tea. DMBA is an homologue of 1,3-dimethylamylamine (DMAA) which the US Food and Drug Administration has attempted to remov...

  10. Inhibitory effects of Zengshengping fractions on DMBA-induced buccal pouch carcinogenesis in hamsters.

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    Guan, Xiao-Bing; Sun, Zheng; Chen, Xiao-Xin; Wu, Hong-Ru; Zhang, Xin-Yan

    2012-01-01

    Zengshengping (ZSP) tablets had inhibitory effects on oral precancerous lesions by reducing the incidence of oral cancer. However, the severe liver toxicity caused by systemic administration of ZSP limits the long-term use of this anti-cancer drug. The purpose of this study was to evaluate the tumor inhibitory effects due to the topical application of extracts from ZSP, a Chinese herbal drug, on 7, 12-dimethlbenz(a)anthracene (DMBA) induced oral tumors in hamsters. The study also investigated the anti-cancer mechanisms of the ZSP extracts on oral carcinogenesis. DMBA (0.5%) was applied topically to the buccal pouches of Syrian golden hamsters (6 - 8 weeks old) three times per week for six weeks in order to induce the development of oral tumors. Different fractions of ZSP were either applied topically to the oral tumor lesions or fed orally at varying dosages to animals with oral tumors for 18 weeks. Tumor volume was measured by histopathological examination. Tumor cell proliferation was evaluated by counting BrdU labeled cells and by Western blotting for mitogen-activated protein kinase (MAPK) protein levels. The protein levels of apoptosis marker Caspase-3 and regulator Bcl-2 protein were also measured by Western blotting. Topical application of DMBA to the left pouch of hamsters induced oral tumor formation. Animals treated with DMBA showed a loss in body weight while animals treated with ZSP maintained normal body weights. Both the ZSP n-butanol fraction and water fraction significantly reduced tumor volume by 32.6% (P oral tumor lesions and reduced the expression level of MAPK. In addition, ZSP promoted tumor cell apoptosis by increasing Caspase-3 expression but decreasing Bcl-2 protein production. The n-butanol and water fractions of ZSP are effective at inhibiting tumor cell proliferation and stimulating apoptosis in oral cancer suggesting that these fractions have chemopreventive effects on DMBA induced oral carcinogenesis.

  11. Charles River Sprague Dawley rats lack early age-dependent susceptibility to DMBA-induced mammary carcinogenesis.

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    Gear, R B; Yan, M; Schneider, J; Succop, P; Heffelfinger, S C; Clegg, D J

    2007-10-04

    Developmental stages of mammary glands influence their susceptibility to initiating events related to carcinogenesis. The "window of susceptibility" to mammary carcinogenesis is classically defined as the time in early puberty when the mammary gland morphology is most sensitive to initiation events. Administration of the polyaromatic hydrocarbon, 7,12-dimethylbenz(a)anthracene (DMBA), in a single oral dose yields maximal mammary tumor formation when administered in this "window". We examined the DMBA treated mammary glands, precursor lesions, and morphology of the uninvolved mammary epithelium for the first 100 days of life for Charles River Sprague Dawley CD(R) IGS. Our goal was to determine the DMBA dose at which 50% of the rats (IC50) developed carcinoma in situ (CIS) within three months of dosing. Here we demonstrate, rather than the classical U-shaped dose curve in which there is maximum sensitivity for DMBA at 50 days, there is an increasing degree of sensitivity with age in the CD(R) IGS rat. Additionally, we report that vehicle-treated animals developed mammary CIS without any known initiator, and 100 day virgin animals demonstrated lactational changes, independent of DMBA exposure or dose. Lastly, we demonstrate this strain of virgin female rats has elevated pituitary prolactin immunoreactivity independent of the level of mammary differentiation. We conclude this strain of Charles River Sprague Dawley rats has prolactin-induced pituitary stimulation, and therefore, the window of susceptibility for mammary tumorigenesis is absent.

  12. CD48-deficient T-lymphocytes from DMBA-treated rats have de novo mutations in the endogenous Pig-a gene.

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    Dobrovolsky, Vasily N; Revollo, Javier; Pearce, Mason G; Pacheco-Martinez, M Monserrat; Lin, Haixia

    2015-10-01

    A major question concerning the scientific and regulatory acceptance of the rodent red blood cell-based Pig-a gene mutation assay is the extent to which mutants identified by their phenotype in the assay are caused by mutations in the Pig-a gene. In this study, we identified T-lymphocytes deficient for the glycosylphosphatidylinositol-anchored surface marker, CD48, in control and 7,12-dimethylbenz[a]anthracene (DMBA)-treated rats using a flow cytometric assay and determined the spectra of mutations in the endogenous Pig-a gene in these cells. CD48-deficient T-cells were seeded by sorting at one cell per well into 96-well plates, expanded into clones, and exons of their genomic Pig-a were sequenced. The majority (78%) of CD48-deficient T-cell clones from DMBA-treated rats had mutations in the Pig-a gene. The spectrum of DMBA-induced Pig-a mutations was dominated by mutations at A:T, with the mutated A being on the nontranscribed strand and A → T transversion being the most frequent change. The spectrum of Pig-a mutations in DMBA-treated rats was different from the spectrum of Pig-a mutations in N-ethyl-N-nitrosourea (ENU)-treated rats, but similar to the spectrum of DMBA mutations for another endogenous X-linked gene, Hprt. Only 15% of CD48-deficient mutants from control animals contained Pig-a mutations; T-cell biology may be responsible for a relatively large fraction of false Pig-a mutant lymphocytes in control animals. Among the verified mutants from control rats, the most common were frameshifts and deletions. The differences in the spectra of spontaneous, DMBA-, and ENU-induced Pig-a mutations suggest that the flow cytometric Pig-a assay detects de novo mutation in the endogenous Pig-a gene. © 2015 Wiley Periodicals, Inc.

  13. Anti-tumor activity of Aloe vera against DMBA/croton oil-induced skin papillomagenesis in Swiss albino mice.

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    Saini, M; Goyal, Pradeep Kumar; Chaudhary, Geeta

    2010-01-01

    Human populations are increasingly exposed to various carcinogens such as chemicals, radiation, and viruses in the environment. Chemopreventive drugs of plant origin are a promising strategy for cancer control because they are generally nontoxic or less toxic than synthetic che-mopreventive agents, and can be effective at different stages of carcinogenesis. The present investigation was undertaken to explore the antitumor activity of topical treatment with aloe vera (Aloe vera) gel, oral treatment with aloe vera extract, and topical and oral treatment with both gel and extract in stage-2 skin carcinogenesis in Swiss albino mice induced by 7,12-dim ethylbenz(a)anthracene (DMBA) and promoted croton (Croton tiglium) oil. The animals were randomly divided into 4 groups and treated as follows: Group I, DMBA + croton oil only (controls); Group II, DMBA + croton oil + topical aloe vera gel; Group III, DMBA + croton oil + oral aloe vera extract; Group I V, DMBA + croton oil + topical aloe vera gel + oral aloe vera extract. Results showed that body weight was significantly increased from 78.6% in the control group (Group I) to 92.5%, 87.5%, and 90.0% in Groups II, III, and I V, respectively. A 100% incidence of tumor development was noted in Group I, which was decreased to 50%, 60%, and 40% in Groups II, III, and I V, respectively. Also in Groups II, III, and IV, the cumulative number of papillomas was reduced significantly from 36 to 12, 15, and 11; tumor yield from 3.6 to 1.2, 1.5, and 1.1; and tumor burden from 3.6 to 2.4, 2.50, and 2.75, respectively, after treatment with aloe vera. Conversely, the average latent period increased significantly from 4.9 (Group I) to 5.23, 5.0, and 6.01 weeks in Groups II, III, and I V, respectively. We conclude that aloe vera protects mice against DMBA/croton oil-induced skin papillomagenesis, likely due to the chemopreventive activity of high concentrations of antioxidants such as vitamins A, C, and E; glutathione peroxidase; several

  14. Coordination, non-coordination and semi-coordination of perchlorates in the lanthanide adducts Ln (CLO4)3. 6dmba

    International Nuclear Information System (INIS)

    Tfouni, E.; Giesbrecht, E.

    1983-01-01

    The coordination or not of the perchlorate anions in the previously reported Ln(CLO 4 ) 3 .6 dmba is discussed. The analysis of the infrared spectral data and molar conductance data indicate that they may be formulated as [Ln(dmba) 6 (CLO 4 )n] (CLO 4 ) sub(3-n), n=0,1,2. The individual compounds may be a mixture of species with different n values and/or pure compounds with semi-coordinated and non-coordinated perchlorates. (Author) [pt

  15. Combination therapies in adjuvant with topical ALA-mediated photodynamic therapy for DMBA-induced hamster buccal pouch premalignant lesions

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    Yang, Deng-Fu; Hsu, Yih-Chih

    2012-03-01

    In Taiwan, oral cancer has becomes the fastest growth male cancer disease due to the betel nut chewing habit combing with smoking and alcohol-drinking lifestyle of people. In order to eliminate the systemic phototoxic effect of 5-aminolevulinic acid (ALA), this study was designed to use a topical ALA-mediated PDT for treatment of DMBA-induced hamster buccal pouch precancerous lesions. DMBA was applied to one of the buccal pouches of hamsters thrice a week for 10 to 12 weeks. Cancerous lesions were induced and proven by histological examination. These DMBA-induced cancerous lesions were used for testing the efficacy of topical ALA-mediated PDT. Before PDT, fluorescence spectroscopy was used to determine when ALA reached its peak level in the lesional epithelial cells after topical application of ALA gel. We found that ALA reached its peak level in precancerous lesions about 2.5 hrs after topical application of ALA gel. The cancerous lesions in hamsters were then treated with topical ALA -mediated PDT with light exposure dose of 150 J/cm2 using LED 635 nm fiber-guided light device. Visual examination demonstrated that adjuvant topical ALA -mediated PDT group has shown better therapeutic results in compared to those of non-adjuvant topical ALA-mediated PDT group for DMBA-induced hamster buccal pouch precancerous lesions.

  16. Scaffold attachment factor B1 (SAFB1 heterozygosity does not influence Wnt-1 or DMBA-induced tumorigenesis

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    Lewis Michael T

    2009-03-01

    Full Text Available Abstract Background Scaffold Attachment Factor B1 (SAFB1 is a multifunctional protein which has been implicated in breast cancer previously. We recently generated SAFB1 knockout mice (SAFB1-/-, but pleiotropic phenotypes including high lethality, dwarfism associated with low IGF-I levels, and infertility and subfertility in male and female mice, respectively, do not allow for straightforward tumorigenesis studies in these mice. Therefore, we asked whether SAFB1 heterozygosity would influence tumor development and progression in MMTV-Wnt-1 oncomice or DMBA induced tumorigenicity, in a manner consistent with haploinsufficiency of the remaining allele. Methods We crossed female SAFB1+/- (C57B6/129 mice with male MMTV-Wnt-1 (C57B6/SJL mice to obtain SAFB1+/+/Wnt-1, SAFB1+/-/Wnt-1, and SAFB1+/- mice. For the chemical induced tumorigenesis study we treated 8 weeks old SAFB1+/- and SAFB+/+ BALB/c mice with 1 mg DMBA once per week for 6 weeks. Animals were monitored for tumor incidence and tumor growth. Tumors were characterized by performing H&E, and by staining for markers of proliferation and apoptosis. Results We did not detect significant differences in tumor incidence and growth between SAFB1+/+/Wnt-1 and SAFB1+/-/Wnt-1 mice, and between DMBA-treated SAFB1+/+ and SAFB1+/-mice. Histological evaluation of tumors showed that SAFB1 heterozygosity did not lead to changes in proliferation or apoptosis. There were, however, significant differences in the distribution of tumor histologies with an increase in papillary and cribriform tumors, and a decrease in squamous tumors in the SAFB1+/-/Wnt-1 compared to the SAFB1+/+/Wnt-1 tumors. Of note, DMBA treatment resulted in shortened survival of SAFB1+/- mice compared to their wildtype littermates, however this trend did not reach statistical significance. Conclusion Our data show that SAFB1 heterozygosity does not influence Wnt-1 or DMBA-induced mammary tumorigenesis.

  17. Topical photosan-mediated photodynamic therapy for DMBA-induced hamster buccal pouch early cancer lesions: an in vivo study

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    Hsu, Yih-Chih; Chang, Walter Hong-Shong; Chang, Junn-Liang; Liu, Kuang-Ting; Chiang, Chun-Pin; Liu, Chung-Ji; Chen, Chih-Ping

    2011-03-01

    Oral cancer has becomes the most prominent cancer disease in recent years in Taiwan. The reason is the betel nut chewing habit combing with smoking and alcohol-drinking lifestyle of people results in oral cancer becomes the fastest growth incident cancer amongst other major cancer diseases. In previous studies showed that photosan, haematoporphyrin derivative (HPD), has demonstrated effective PDT results on human head and neck disease studies. To avoid the systemic phototoxic effect of photosan, this study was designed to use a topical photosan-mediated PDT for treatment of DMBA-induced hamster buccal pouch cancerous lesions. DMBA was applied to one of the buccal pouches of hamsters thrice a week for 10 to 12 weeks. Cancerous lesions were induced and proven by histological examination. These DMBA-induced cancerous lesions were used for testing the efficacy of topical photosan-mediated PDT. Before PDT, fluorescence spectroscopy was used to determine when photosan reached its peak level in the lesional epithelial cells after topical application of photosan gel. We found that photosan reached its peak level in cancerous lesions about 13.5 min after topical application of photosan gel. The cancerous lesions in hamsters were then treated with topical photosan-mediated PDT (fluence rate: 600 mW/cm2; light exposure dose 200 J/cm2) using the portable Lumacare 635 nm fiber-guided light device. Visual examination demonstrated that topical photosan-mediated PDT was an applicable treatment modality for DMBA-induced hamster buccal pouch cancerous lesions.

  18. Effect of primrose oil and corn oil diets on eicosanoid synthesis by rat mammary tumor induced by dimethylbenzanthracene (DMBA)

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    El-Ela, S.H.A.; Bunce, O.R.

    1986-03-01

    Evening primrose oil (PO) contains 9% gamma-linolenic acid (GLA) and 75% linoleic acid (LA) each of which are prostaglandin precursors. Corn oil (CO) contains 60% linoleic acid. Fifty day old virgin female rats were given DMBA (5 mg, intragastric). Three weeks post DMBA the rats were separated into two dietary groups of 20% PO and 20% CO, respectively. At 16 weeks post DMBA the rats were killed and mammary tumors analyzed by RIA for PGE/sub 1/, PGE/sub 2/, and 6-keto F/sub 1..cap alpha... PGE/sub 1/ levels in PO fed animals were increased two fold over those fed CO indicating that it is possible to shunt GLA toward monoenoic eicosanoid synthesis. However PGE/sub 2/ and 6 keto F/sub 1..cap alpha../ levels were 5x higher in PO compared to CO. Although this could be attributed to higher cis linoleic acid content of PO, more subtle mechanisms may be responsible.

  19. Comparsion of light dose on topical ALA-mediated photodynamic therapy for DMBA-induced hamster buccal pouch premalignant lesions

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    Yang, Deng-Fu; Tseng, Meng-Ke; Liu, Chung-Ji; Hsu, Yih-Chih

    2012-03-01

    Oral cancer has becomes the most prominent male cancer disease due to the local betel nut chewing habit combing with smoking and alcohol-drinking lifestyle. In order to minimize the systemic phototoxic effect of 5-aminolevulinic acid (ALA), this study was designed to use a topical ALA-mediated PDT for treatment of DMBA-induced hamster buccal pouch cancerous lesions. DMBA was applied to one of the buccal pouches of hamsters thrice a week for 8 to 10 weeks. Precancerous lesions were induced and proven by histological examination. These DMBA-induced cancerous lesions were used for testing the efficacy of topical ALA -mediated PDT. We found that ALA reached its peak level in cancerous lesions about 2.5 hrs after topical application of ALA gel. The precancerous lesions in hamsters were then treated with topical ALA -mediated PDT with light exposure dose of 75 and 100 J/cm2 using LED 635 nm Wonderlight device. It is suggesting that optimization of the given light dose is critical to the success of PDT results.

  20. Tumor-associated proteins in rat submandibular gland induced by DMBA and irradiation

    International Nuclear Information System (INIS)

    Oh, Sung Ook; Choi, Soon Chul; Park, Tae Won; You, Dong Soo

    1997-01-01

    This study was performed in order to identify changes of the plasma membrane proteins in rat submandibular gland tumors induced by 7,12-dimethylbenz[a]anthracene [DMBA] and X-irradiation. Two kinds of tumor associated membrane proteins (protein A and B) were isolated with 3 M KCl extraction from rat submandibular gland tumors induced by DMBA and X-irradiation. To identify their antigenicities, immunoelectrophoresis and double immunodiffusion was carried out with various proteins extracted from liver, heart, skin and pancreas of adult rats and from embryonic liver, heart and skin. The rabbit antisera against the protein A did not cross-react with any of the proteins extracted from the above mentioned tissues, suggesting that protein A might be tumor specific antigen. However, the rabbit antisera against protein B was precipitated with proteins extracted from the liver of adult and embryonic rats. Polyacrylamide gel electrophoresis of these two proteins (A and B) showed that protein A was a dimer with molecular weights of 69,000 and 35,000 dalton, whereas protein B was a monomer with molecular weight of 50,000 dalton.

  1. Dietary turmeric modulates DMBA-induced p21ras, MAP kinases and AP-1/NF-κB pathway to alter cellular responses during hamster buccal pouch carcinogenesis

    International Nuclear Information System (INIS)

    Garg, Rachana; Ingle, Arvind; Maru, Girish

    2008-01-01

    The chemopreventive efficacy of turmeric has been established in experimental systems. However, its mechanism(s) of action are not fully elucidated in vivo. The present study investigates the mechanism of turmeric-mediated chemoprevention in 7,12-dimethylbenz(a)anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis at 2, 4, 6, 10 and 12 weeks. Dietary turmeric (1%) led to decrease in DMBA-induced tumor burden and multiplicity, and enhanced the latency period in parallel, to its modulatory effects on oncogene products and various cellular responses during HBP tumorigenesis. DMBA-induced expression of ras oncogene product, p21 and downstream target, the mitogen-activated protein kinases were significantly decreased by turmeric during HBP carcinogenesis. Turmeric also diminished the DMBA-induced mRNA expression of proto-oncogenes (c-jun, c-fos) and NF-κB, leading to decreased protein levels and in further attenuation of DMBA-induced AP-1/NF-κB DNA-binding in the buccal pouch nuclear extracts. Besides, buccal pouch of hamsters receiving turmeric diet showed significant alterations in DMBA-induced effects: (a) decrease in cell proliferation (diminished PCNA and Bcl2 expression), (b) enhanced apoptosis (increased expression of Bax, caspase-3 and apoptotic index), (c) decrease in inflammation (levels of Cox-2, the downstream target of AP-1/NF-κB, and PGE2) and (d) aberrant expression of differentiation markers, the cytokeratins (1, 5, 8, and 18). Together, the protective effects of dietary turmeric converge on augmenting apoptosis of the initiated cells and decreasing cell proliferation in DMBA-treated animals, which in turn, is reflected in decreased tumor burden, multiplicity and enhanced latency period. Some of these biomarkers are likely to be helpful in monitoring clinical trials and evaluating drug effect measurements

  2. Pancreatic intraepithelial neoplasia and ductal adenocarcinoma induced by DMBA in mice: effects of alcohol and caffeine Neoplasia pancreática intraepithelial e adenocarcinoma ductal induzidos pelo DMBA em camundongos: efeitos do álcool e da cafeína

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    Luiz Roberto Wendt

    2007-06-01

    Full Text Available PURPOSE: To evaluate the effects of alcohol and caffeine in a pancreatic carcinogenesis mouse model induced by 7,12-dimethylbenzantracene (DMBA, according to the PanIN classification system. METHODS: 120 male, Mus musculus, CF-1 mice were divided into four groups. Animals received either water or caffeine or alcohol or alcohol + caffeine in their drinking water. In all animals, 1 mg of DMBA was implanted into the head of the pancreas. After 30 days, euthanasia was performed; excised pancreata were then fixed in formalin, stained with hematoxylin-eosin and categorized as follows: normal ducts, reactive hyperplasia, PanIN-1A, PanIN-1B, PanIN-2, PanIN-3 or adenocarcinoma. RESULTS: PanIN lesions were verified in all groups. Adenocarcinoma was detected in 15% of animals in the caffeine group, 16.6% in the water group, 23.8% in the alcohol + caffeine group and 52.9% in the alcohol group (POBJETIVO: Avaliar os efeitos do álcool e da cafeína na carcinogênese pancreática induzida pelo 7,12-dimetilbenzantraceno (DMBA em camundongos, descrevendo as lesões de acordo com a classificação das neoplasias pacreáticas intraepiteliais (PanIN. MÉTODOS: 120 camundogos machos, Mus musculus, CF-1 foram divididos em quatro grupos. Animais receberam água ou cafeína ou álcool ou álcool + cafeína para beber. Em todos animais, 1 mg de DMBA foi implantado na cabeça do pâncreas. Após 30 dias, eutanásia foi realizada, o pâncreas foi removido, fixado em formalina e corado com hematoxilina e eosina sendo classificado em: ductos normais, hiperplasia reativa, PanIN-1A, PanIN-1B, PanIN-2, PanIN-3 ou adenocarcinoma. RESULTADOS: Neoplasias pancreáticas intraepiteliais foram encontradas em todos grupos. Adenocarcinoma foi detectado em 15% dos animais do grupo cafeína, 16,6% do grupo água, 23,8% do grupo álcool + cafeína e 52,9% do grupo álcool (P<0,05. CONCLUSÕES: O modelo experimental de carcinogênese pancreática em camundongos utilizando DMBA induz

  3. Promoting Effects of Milk on the Development of 7,12-dimethylbenz(a)anthracene (DMBA)-induced Mammary Tumors in Rats

    International Nuclear Information System (INIS)

    Ma, De-Fu; Katoh, Ryohei; Zhou, Hong; Wang, Pei-Yu

    2007-01-01

    To assess the effect of milk on the development of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumors, 48 female Sprague-Dawley rats treated with DMBA were divided into 3 groups and given 1 of 3 test solutions for 20 weeks as their drinking liquid: milk, estrone sulfate solution or tap water. The milk group showed a significantly great incidence (75%) in tumor development compared with the water group (38%) and was comparable to the estrone sulfate group (69%). Mean tumor number per rat in the milk group was significantly higher than that in the water group (p=0.009). We classified the mammary tumors into three histological types: intraductal papilloma, fibroadenoma, and adenocarcinoma. Although the percent of intraductal papilloma and fibroadenoma was almost same among the three groups, malignant tumor was found only in the milk and estrone sulfate groups. In conclusion, our results indicate that milk as well as estrone sulfate promotes the development of DMBA-induced mammary tumors in rat and could be associated with the occurrence of adenocarcinoma

  4. Stokes shift spectroscopy for the early diagnosis of epithelial precancers in DMBA treated mouse skin carcinogenesis

    Science.gov (United States)

    Jeyasingh, Ebenezar; Singaravelu, Ganesan; Prakasarao, Aruna

    2018-02-01

    In this study, we aim to characterize the tissue transformation in dimethylbenz(a)anthracene (DMBA) treated mouse skin tumor model using stokes shift spectroscopy (SSS) technique for early detection of the neoplastic changes. Stokes shift (SS) spectra measured by scanning both excitation and emission wavelength simultaneously with a fixed wavelength of interval (Δλ=20 nm) in vivo from 33 DMBA treated animals and 6 control animals. The SS spectra of normal (n=6), hyperplasia (n=10), dysplasia (n=10), and WDSCC (n=13) of mice skin shows the distinct peaks around 300, 350, and 386 nm may be attributed to tryptophan, collagen, and NADH respectively. From the observed spectral differences and the ratio variables that resulted in better classification between groups, it is concluded that tryptophan, collagen, and NADH are the key fluorophores that undergo changes during tissue transformation process and hence they can be targeted as tumor markers for early neoplastic changes.

  5. Zyflamend reduces LTB4 formation and prevents oral carcinogenesis in a 7,12-dimethylbenz[alpha]anthracene (DMBA)-induced hamster cheek pouch model.

    Science.gov (United States)

    Yang, Peiying; Sun, Zheng; Chan, Diana; Cartwright, Carrie A; Vijjeswarapu, Mary; Ding, Jibin; Chen, Xiaoxin; Newman, Robert A

    2008-11-01

    Aberrant arachidonic acid metabolism, especially altered cyclooxygenase and 5-lipoxygenase (LOX) activities, has been associated with chronic inflammation as well as carcinogenesis in human oral cavity tissues. Here, we examined the effect of Zyflamend, a product containing 10 concentrated herbal extracts, on development of 7,12-dimethylbenz[alpha]anthracene (DMBA)-induced inflammation and oral squamous cell carcinoma (SCC). A hamster cheek pouch model was used in which 0.5% DMBA was applied topically onto the left cheek pouch of male Syrian golden hamsters either three times per week for 3 weeks (short term) or 6 weeks (long term). Zyflamend was then applied topically at one of three different doses (25, 50 and 100 microl) onto the left cheek pouch three times for 1 week (short-term study) or chronically for 18 weeks. Zyflamend significantly reduced infiltration of inflammatory cells, incidence of hyperplasia and dysplastic lesions, bromodeoxyuridine-labeling index as well as number of SCC in a concentration-dependent manner. Application of Zyflamend (100 microl) reduced formation of leukotriene B(4) (LTB(4)) by 50% compared with DMBA-treated tissues. The reduction of LTB(4) was concentration dependent. The effect of Zyflamend on inhibition of LTB(4) formation was further confirmed with in vitro cell-based assay. Adding LTB(4) to RBL-1 cells, a rat leukemia cell line expressing high levels of 5-LOX and LTA(4) hydrolase, partially blocked antiproliferative effect of Zyflamend. This study demonstrates that Zyflamend inhibited LTB(4) formation and modulated adverse histopathological changes in the DMBA-induced hamster cheek pouch model. The study suggests that Zyflamend might prevent oral carcinogenesis at the post-initiation stage.

  6. Enhanced efficacy and specificity of epithelial ovarian carcinogenesis by embedding a DMBA-coated cloth strip in the ovary of rat

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    Huang Yiping

    2012-09-01

    Full Text Available Abstract Background Ovarian cancer is predominant of epithelial cell origin and often present at an advanced stage with poor prognosis. Most animal models of ovarian carcinoma yield thecal/granulose cell tumors, rather than adenocarcinomas. The best reported induction rate of adenocarcinoma in rats is 10-45% by an ovarian implantation of 7, 12-dimethylbenz[a]anthracene (DMBA coated silk suture. We provided an improved procedure to construct the model by the ovarian implantation of DMBA-coated cloth strip. Methods A sterile suture (as S group or a piece of cloth strip (as CS group was soaked in DMBA before ovarian implantation in Wistar rats. Tumor size, incidence rate and pathological type were analyzed. Results Ovarian tumors in rats of CS group were first noted at 16 wk post implantation and reached a cumulative incidence of 75% (96/128 at 32 wk, while the tumor incidence rate in S group at 32 wk was only 46.25% (37/80. The tumor size in CS group (3.63 ± 0.89 cm was larger than that of S group (2.44 ± 1.89 cm (P  Conclusion The model in our study yields much higher incidence and specificity of epithelial derived tumors and showed histological similarities to human ovarian cancers, which would be more suitable for therapeutic research.

  7. A synthetic coumarin (4-methyl-7 hydroxy coumarin) has anti-cancer potentials against DMBA-induced skin cancer in mice.

    Science.gov (United States)

    Bhattacharyya, Soumya S; Paul, Saili; Mandal, Sushil K; Banerjee, Antara; Boujedaini, Naoual; Khuda-Bukhsh, Anisur R

    2009-07-01

    Scopoletin, an alkaloid separated from ethanolic extract of the medicinal plant, Gelsemium sempervirens (Fam: Loganiaceae) has been reported to have anti-cancer potentials. The synthetic coumarin (4-Methyl-7 hydroxy coumarin) derived from resorcinol and ethyl aceto-acetate in presence of concentrated sulphuric acid is structurally close to scopoletin, being a coumarin derivative. Whether this synthetic compound also has anti-cancer potentials has been evaluated in vivo on DMBA (7,12-Dimethylbenz[a]anthracene) induced skin cancer in mice by analyzing results of several cytogenetic endpoints, Comet assay, and fluorescence activated cell sorting (FACS). Further, expressions of signal proteins like Aryl hydrocarbon receptor , p53, PCNA, Akt, Bcl-2, Bcl-xL, Bad, Bax, NF-kappaB Apaf, IL-6, Cytochrome-c, Caspase-3 and Caspase-9 were studied by immunoblot analysis along with histology of skin and immuno-histochemical localization of Aryl hydrocarbon receptor and PCNA in DMBA treated mice vis-a-vis carcinogen treated synthetic coumarin fed mice. Feeding of this synthetic coumarin induced positive modulations in expression of all biomarkers in DMBA administered mice, giving clues on its possible signaling pathway(s) - primarily through down-regulation of Aryl hydrocarbon receptor and PCNA and up-regulation of apoptotic proteins like Bax, Bad, Cytochrome c, Apaf, Caspase-3 and Caspase-9, resulting in an appreciable reduction in growth of papilloma in mice. Therefore, this synthetic coumarin shows promise for use in cancer therapy, particularly in skin cancer.

  8. Inhibitory effect of vitamin D-binding protein-derived macrophage activating factor on DMBA-induced hamster cheek pouch carcinogenesis and its derived carcinoma cell line.

    Science.gov (United States)

    Toyohara, Yukiyo; Hashitani, Susumu; Kishimoto, Hiromitsu; Noguchi, Kazuma; Yamamoto, Nobuto; Urade, Masahiro

    2011-07-01

    This study investigated the inhibitory effect of vitamin D-binding protein-derived macrophage-activating factor (GcMAF) on carcinogenesis and tumor growth, using a 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced hamster cheek pouch carcinogenesis model, as well as the cytocidal effect of activated macrophages against HCPC-1, a cell line established from DMBA-induced cheek pouch carcinoma. DMBA application induced squamous cell carcinoma in all 15 hamsters of the control group at approximately 10 weeks, and all 15 hamsters died of tumor burden within 20 weeks. By contrast, 2 out of the 14 hamsters with GcMAF administration did not develop tumors and the remaining 12 hamsters showed a significant delay of tumor development for approximately 3.5 weeks. The growth of tumors formed was significantly suppressed and none of the hamsters died within the 20 weeks during which they were observed. When GcMAF administration was stopped at the 13th week of the experiment in 4 out of the 14 hamsters in the GcMAF-treated group, tumor growth was promoted, but none of the mice died within the 20-week period. On the other hand, when GcMAF administration was commenced after the 13th week in 5 out of the 15 hamsters in the control group, tumor growth was slightly suppressed and all 15 hamsters died of tumor burden. However, the mean survival time was significantly extended. GcMAF treatment activated peritoneal macrophages in vitro and in vivo, and these activated macrophages exhibited a marked cytocidal effect on HCPC-1 cells. Furthermore, the cytocidal effect of activated macrophages was enhanced by the addition of tumor-bearing hamster serum. These findings indicated that GcMAF possesses an inhibitory effect on tumor development and growth in a DMBA-induced hamster cheek pouch carcinogenesis model.

  9. Topical chlorophyll-pheophytin derivative-mediated photodynamic therapy for DMBA-induced hamster buccal pouch premaligant lesions: an in vivo study

    Science.gov (United States)

    Hsu, Yih-Chih; Chiang, Chung-Pin; Chen, Jian Wen; Lee, Jeng-Woei; How, Mon-Hsin

    2010-02-01

    In Taiwan, oral cancer has become a prominent cancer because of its highest annual increase rate among all cancer diseases. Betel quid chewing habit is a major risk factor for oral precancerous and cancerous lesions and there are more than two million people who have this habit in Taiwan. Our previous studies showed that chlorophyll-pheophytin derivative (CPD)-mediated PDT is very effective for killing of SCC-4 cell lines in vitro. In order to decrease the systemic phototoxic effect of CPD, this study was designed to use a topical CPD-mediated PDT for treatment of DMBA-induced hamster buccal pouch precancerous lesions. DMBA was applied to one of the buccal pouches of hamsters thrice a week for 8 to 10 weeks. Precancerous lesions of moderate to severe dysplasia were induced and proven by histological examination. These induced precancerous lesions were used for testing the efficacy of topical CPD-mediated PDT. Before PDT, fluorescence spectroscopy was used to determine when CPD reached its peak level in the lesional epithelial cells after topical application of CPD gel. We found that CPD reached its peak level in precancerous lesions about 1 hour (range, 0 to 30 hours) after topical application of CPD gel. The precancerous lesions in hamsters were then treated with topical CPD-mediated PDT (fluence rate: 200 mW/cm2; light exposure dose 100 J/cm2) using the portable WonderLight LED 635 nm fiber-guided light device once or twice a week. Visual and histological examination demonstrated that topical CPD-mediated PDT was partially effective treatment modality for DMBA-induced hamster buccal pouch precancerous lesions.

  10. Characterization of synergistic anti-cancer effects of docosahexaenoic acid and curcumin on DMBA-induced mammary tumorigenesis in mice

    International Nuclear Information System (INIS)

    Siddiqui, Rafat A; Harvey, Kevin A; Walker, Candace; Altenburg, Jeffrey; Xu, Zhidong; Terry, Colin; Camarillo, Ignacio; Jones-Hall, Yava; Mariash, Cary

    2013-01-01

    The major obstacles to the successful use of individual nutritional compounds as preventive or therapeutic agents are their efficacy and bioavailability. One approach to overcoming this problem is to use combinations of nutrients to induce synergistic effects. The objective of this research was to investigate the synergistic effects of two dietary components: docosahexaenoic acid (DHA), an omega-3 fatty acid present in cold-water fish, and curcumin (CCM), an herbal nutrient present in turmeric, in an in vivo model of DMBA-induced mammary tumorigenesis in mice. We used the carcinogen DMBA to induce breast tumors in SENCAR mice on control, CCM, DHA, or DHA + CCM diets. Appearance and tumor progression were monitored daily. The tumors were harvested 15 days following their first appearance for morphological and immunohistological analysis. Western analysis was performed to determine expression of maspin and survivin in the tumor tissues. Characterization of tumor growth was analyzed using appropriate statistical methods. Otherwise all other results are reported as mean ± SD and analyzed with one-way ANOVA and Tukey’s post hoc procedure. Analysis of gene microarray data indicates that combined treatment with DHA + CCM altered the profile of “PAM50” genes in the SK-BR-3 cell line from an ER - /Her-2 + to that resembling a “normal-like” phenotype. The in vivo studies demonstrated that DHA + CCM treatment reduced the incidence of breast tumors, delayed tumor initiation, and reduced progression of tumor growth. Dietary treatment had no effect on breast size development, but tumors from mice on a control diet (untreated) were less differentiated than tumors from mice fed CCM or DHA + CCM diets. The synergistic effects also led to increased expression of the pro-apoptotic protein, maspin, but reduced expression of the anti-apoptotic protein, survivin. The SK-BR-3 cells and DMBA-induced tumors, both with an ER - and Her-2 + phenotype, were affected by the

  11. Cancer-promoting effect of capsaicin on DMBA/TPA-induced skin tumorigenesis by modulating inflammation, Erk and p38 in mice.

    Science.gov (United States)

    Liu, Zhaoguo; Zhu, Pingting; Tao, Yu; Shen, Cunsi; Wang, Siliang; Zhao, Lingang; Wu, Hongyan; Fan, Fangtian; Lin, Chao; Chen, Chen; Zhu, Zhijie; Wei, Zhonghong; Sun, Lihua; Liu, Yuping; Wang, Aiyun; Lu, Yin

    2015-07-01

    Epidemiologic and animal studies revealed that capsaicin (8-methyl-N-vanillyl-6-noneamide) can act as a carcinogen or cocarcinogen. However, the influence of consumption of capsaicin-containing foods or vegetables on skin cancer patients remains largely unknown. In the present study, we demonstrated that capsaicin has a cocarcinogenic effect on 9, 10-dimethylbenz[a]anthracene (DMBA)/12-O-tetradecanoylphorbol-13-acetate (TPA)-induced skin tumorigenesis. Our results showed that topical application of capsaicin on the dorsal skin of DMBA-initiated and TPA-promoted mice could significantly accelerate tumor formation and growth and induce more and larger skin tumors than the model group (DMBA + TPA). Moreover, capsaicin could promote TPA-induced skin hyperplasia and tumor proliferation. Mechanistic study found that inflammation-related factors cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) were highly elevated by pretreatment with capsaicin, suggesting an inflammation-dependent mechanism. Furthermore, mice that were administered capsaicin exhibited significant up-regulation of phosphorylation of nuclear factor kappaB (NF-κB), Erk and p38 but had no effect on JNK. Thus, our results indicated that inflammation, Erk and P38 collectively played a crucial role in cancer-promoting effect of capsaicin on carcinogen-induced skin cancer in mice. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Growth Pattern of Follicles in Mice after X-Ray or DMBA Induction of Ovarian Tumours

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, T.; Krarup, T.; Peters, H.; Faber, M. [Finsen Institute, Copenhagen (Denmark)

    1969-11-15

    Whole-body X-irradiation of mice as well as treatment with the carcinogenic hydrocarbon 9:10-dimethyl-1:2 benzanthracene results in the formation of ovarian tumours. After both experimental procedures an immediate destruction of the small oocytes is initiated. Tumours arise in ovaries totally depleted of oocytes. The question arises how the two carcinogenic stimuli, besides destroying small oocytes, will influence the only cell population in the ovary that proliferates, namely granulosa cells in medium and large follicles. This was investigated by autoradiographs prepared at different time intervals after intraperitoneal injection of {sup 3}H-thymidine. Two parameters were determined in the autoradiographs, i. e. the labelling index of the granulosa cells and the duration of the DNA-synthesis phase. From these parameters the doubling times of the granulosa cells and the growth rate of whole follicles were calculated. It was shown that immediately after X-irradiation and after treatment with DMBA, the labelling index of the granulosa cells increases, which is most marked in the medium follicles. This increase reaches a maximum about 48 hours after both types of treatment and is still recognizable 7 days later. The duration of the S-phase of the individual cells is not significantly affected after DMBA treatment, but in X-irradiated animals it is shortened in the medium follicles 48 hours after irradiation. Simultaneously with the increase in the labelling index there is a shortening of the doubling times of the granular cells and thereby an acceleration of the growth rate of whole follicles. It seems most likely that the increase in labelling index is due partly to an increase in the growth fraction of the granulosa cells and partly to a shortening of the generation time of the proliferating cells. (author)

  13. Activation of P2X7-mediated apoptosis Inhibits DMBA/TPA-induced formation of skin papillomas and cancer in mice

    International Nuclear Information System (INIS)

    Fu, Wen; Gorodeski, George I; McCormick, Tom; Qi, Xiaoping; Luo, Liping; Zhou, Lingyin; Li, Xin; Wang, Bing-Cheng; Gibbons, Heidi E; Abdul-Karim, Fadi W

    2009-01-01

    The study tested the hypothesis that apoptosis can prevent and control growth of neoplastic cells. Previous studies in-vitro have shown that the pro-apoptotic P2X 7 receptor regulates growth of epithelial cells. The specific objective of the present study was to understand to what degree the P2X 7 system controls development and growth of skin cancer in vivo, and what cellular and molecular mechanisms are involved in the P2X 7 action. Skin neoplasias in mice (papillomas, followed by squamous spindle-cell carcinomas) were induced by local application of DMBA/TPA. Experiments in-vitro utilized cultured epidermal keratinocytes generated from wild-type or from P2X 7 -null mice. Assays involved protein immunostaining and Western blots; mRNA real-time qPCR; and apoptosis (evaluated in situ by TUNEL and quantified in cultured keratinocytes as solubilized DNA or by ELISA). Changes in cytosolic calcium or in ethidium bromide influx (P2X 7 pore formation) were determined by confocal laser microscopy. (a) Co-application on the skin of the P2X 7 specific agonist BzATP inhibited formation of DMBA/TPA-induced skin papillomas and carcinomas. At the completion of study (week 28) the proportion of living animals with cancers in the DMBA/TPA group was 100% compared to 43% in the DMBA/TPA+BzATP group. (b) In the normal skin BzATP affected mainly P2X 7 -receptor – expressing proliferating keratinocytes, where it augmented apoptosis without evoking inflammatory changes. (c) In BzATP-treated mice the degree of apoptosis was lesser in cancer than in normal or papilloma keratinocytes. (d) Levels of P2X 7 receptor, protein and mRNA were 4–5 fold lower in cancer tissues than in normal mouse tissues. (e) In cultured mouse keratinocytes BzATP induced apoptosis, formation of pores in the plasma membrane, and facilitated prolonged calcium influx. (f) The BzATP-induced apoptosis, pore-formation and augmented calcium influx had similar dose-dependence for BzATP. (g) Pore formation and the

  14. Activation of P2X7-mediated apoptosis Inhibits DMBA/TPA-induced formation of skin papillomas and cancer in mice

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    Fu Wen

    2009-04-01

    Full Text Available Abstract Background The study tested the hypothesis that apoptosis can prevent and control growth of neoplastic cells. Previous studies in-vitro have shown that the pro-apoptotic P2X7 receptor regulates growth of epithelial cells. The specific objective of the present study was to understand to what degree the P2X7 system controls development and growth of skin cancer in vivo, and what cellular and molecular mechanisms are involved in the P2X7 action. Methods Skin neoplasias in mice (papillomas, followed by squamous spindle-cell carcinomas were induced by local application of DMBA/TPA. Experiments in-vitro utilized cultured epidermal keratinocytes generated from wild-type or from P2X7-null mice. Assays involved protein immunostaining and Western blots; mRNA real-time qPCR; and apoptosis (evaluated in situ by TUNEL and quantified in cultured keratinocytes as solubilized DNA or by ELISA. Changes in cytosolic calcium or in ethidium bromide influx (P2X7 pore formation were determined by confocal laser microscopy. Results (a Co-application on the skin of the P2X7 specific agonist BzATP inhibited formation of DMBA/TPA-induced skin papillomas and carcinomas. At the completion of study (week 28 the proportion of living animals with cancers in the DMBA/TPA group was 100% compared to 43% in the DMBA/TPA+BzATP group. (b In the normal skin BzATP affected mainly P2X7-receptor – expressing proliferating keratinocytes, where it augmented apoptosis without evoking inflammatory changes. (c In BzATP-treated mice the degree of apoptosis was lesser in cancer than in normal or papilloma keratinocytes. (d Levels of P2X7 receptor, protein and mRNA were 4–5 fold lower in cancer tissues than in normal mouse tissues. (e In cultured mouse keratinocytes BzATP induced apoptosis, formation of pores in the plasma membrane, and facilitated prolonged calcium influx. (f The BzATP-induced apoptosis, pore-formation and augmented calcium influx had similar dose-dependence for

  15. Four experimental stimulants found in sports and weight loss supplements: 2-amino-6-methylheptane (octodrine), 1,4-dimethylamylamine (1,4-DMAA), 1,3-dimethylamylamine (1,3-DMAA) and 1,3-dimethylbutylamine (1,3-DMBA).

    Science.gov (United States)

    Cohen, Pieter A; Travis, John C; Keizers, Peter H J; Deuster, Patricia; Venhuis, Bastiaan J

    2017-11-08

    The United States Food and Drug Administration banned the stimulant 1,3-dimethylamylamine (1,3-DMAA) from dietary supplements and warned consumers that the stimulant can pose cardiovascular risks ranging from high blood pressure to heart attacks. We designed our study to determine if a new stimulant similar in structure to 1,3-DMAA has been introduced as an ingredient in supplements sold in the United States (US). We analyzed six brands of supplements that listed an ingredient on the label (e.g., Aconitum kusnezoffii, DMHA or 2-amino-isoheptane) that might refer to an analog of 1,3-DMAA. Supplements were analyzed by two separate laboratories using ultra-high-performance liquid chromatography mass spectrometry and reference standards. Two previously unidentified 1,3-DMAA analogs (2-amino-6-methylheptane [octodrine] and 1,4-dimethylamylamine [1,4-DMAA]) and two banned stimulants (1,3-DMAA and 1,3-dimethylbutylamine [1,3-DMBA]) were identified. Octodrine was found at a dose (±95% CI) of 72 ± 7.5 mg per serving. In Europe, octodrine was previously sold as a pharmaceutical in multi-ingredient medications at dosages from 8 to 33 mg. The quantity of octodrine found in our study was more than twice the largest pharmaceutical dose. The other new stimulant, 1,4-DMAA, has not previously been approved for human consumption, and its safety in humans is unknown. 1,4-DMAA was found at dosages between 21 ± 11 mg to 94 ± 48 mg per serving. In addition, two banned stimulants - 1,3-DMAA and 1,3-DMBA - were also identified: 24 ± 7.6 mg to 35 ± 11 mg of 1,3-DMAA and 51 ± 16 mg of 1,3-DMBA. In one product, 24 ± 7.6 mg of 1,3-DMAA was combined with 21 ± 11 mg of 1,4-DMAA. 1,3-DMAA has been investigated as potentially contributing to hemorrhagic strokes and sudden death, whereas the safety of 1,3-DMBA in humans is unknown. Two banned stimulants (1,3-DMAA and 1,3-DMBA) and two previously unidentified stimulants (1,4-DMAA and

  16. Mutation analysis with random DNA identifiers (MARDI) catalogs Pig-a mutations in heterogeneous pools of CD48-deficient T cells derived from DMBA-treated rats.

    Science.gov (United States)

    Revollo, Javier R; Crabtree, Nathaniel M; Pearce, Mason G; Pacheco-Martinez, M Monserrat; Dobrovolsky, Vasily N

    2016-03-01

    Identification of mutations induced by xenotoxins is a common task in the field of genetic toxicology. Mutations are often detected by clonally expanding potential mutant cells and genotyping each viable clone by Sanger sequencing. Such a "clone-by-clone" approach requires significant time and effort, and sometimes is even impossible to implement. Alternative techniques for efficient mutation identification would greatly benefit both basic and regulatory genetic toxicology research. Here, we report the development of Mutation Analysis with Random DNA Identifiers (MARDI), a novel high-fidelity Next Generation Sequencing (NGS) approach that circumvents clonal expansion and directly catalogs mutations in pools of mutant cells. MARDI uses oligonucleotides carrying Random DNA Identifiers (RDIs) to tag progenitor DNA molecules before PCR amplification, enabling clustering of descendant DNA molecules and eliminating NGS- and PCR-induced sequencing artifacts. When applied to the Pig-a cDNA analysis of heterogeneous pools of CD48-deficient T cells derived from DMBA-treated rats, MARDI detected nearly all Pig-a mutations that were previously identified by conventional clone-by-clone analysis and discovered many additional ones consistent with DMBA exposure: mostly A to T transversions, with the mutated A located on the non-transcribed DNA strand. © 2015 Wiley Periodicals, Inc.

  17. Photodynamic therapy using a novel irradiation source, LED lamp, is similarly effective to photodynamic therapy using diode laser or metal-halide lamp on DMBA- and TPA-induced mouse skin papillomas.

    Science.gov (United States)

    Takahashi, Hidetoshi; Nakajima, Susumu; Ogasawara, Koji; Asano, Ryuji; Nakae, Yoshinori; Sakata, Isao; Iizuka, Hajime

    2014-08-01

    Photodynamic therapy (PDT) is useful for superficial skin tumors such as actinic keratosis and Bowen disease. Although PDT is non-surgical and easily-performed treatment modality, irradiation apparatus is large and expensive. Using 7, 12-dimethylbenz[a]anthracene (DMBA) and 12-ο-tetradecanoylphorbol-13-acetate (TPA)-induced mouse skin papilloma model, we compared the efficacy of TONS501- and ALA-PDT with a LED lamp, a diode laser lamp or a metal-halide lamp on the skin tumor regression. TONS501-PDT using 660 nm LED lamp showed anti-tumor effect at 1 day following the irradiation and the maximal anti-tumor effect was observed at 3 days following the irradiation. There was no significant difference in the anti-tumor effects among TONS501-PDT using LED, TONS501-PDT using diode laser, and 5-aminolevulinic acid hydrochloride (ALA)-PDT using metal-halide lamp. Potent anti-tumor effect on DMBA- and TPA-induced mouse skin papilloma was observed by TONS501-PDT using 660 nm LED, which might be more useful for clinical applications. © 2014 Japanese Dermatological Association.

  18. BAC CGH-array identified specific small-scale genomic imbalances in diploid DMBA-induced rat mammary tumors

    International Nuclear Information System (INIS)

    Samuelson, Emma; Karlsson, Sara; Partheen, Karolina; Nilsson, Staffan; Szpirer, Claude; Behboudi, Afrouz

    2012-01-01

    Development of breast cancer is a multistage process influenced by hormonal and environmental factors as well as by genetic background. The search for genes underlying this malignancy has recently been highly productive, but the etiology behind this complex disease is still not understood. In studies using animal cancer models, heterogeneity of the genetic background and environmental factors is reduced and thus analysis and identification of genetic aberrations in tumors may become easier. To identify chromosomal regions potentially involved in the initiation and progression of mammary cancer, in the present work we subjected a subset of experimental mammary tumors to cytogenetic and molecular genetic analysis. Mammary tumors were induced with DMBA (7,12-dimethylbenz[a]anthrazene) in female rats from the susceptible SPRD-Cu3 strain and from crosses and backcrosses between this strain and the resistant WKY strain. We first produced a general overview of chromosomal aberrations in the tumors using conventional kartyotyping (G-banding) and Comparative Genome Hybridization (CGH) analyses. Particular chromosomal changes were then analyzed in more details using an in-house developed BAC (bacterial artificial chromosome) CGH-array platform. Tumors appeared to be diploid by conventional karyotyping, however several sub-microscopic chromosome gains or losses in the tumor material were identified by BAC CGH-array analysis. An oncogenetic tree analysis based on the BAC CGH-array data suggested gain of rat chromosome (RNO) band 12q11, loss of RNO5q32 or RNO6q21 as the earliest events in the development of these mammary tumors. Some of the identified changes appear to be more specific for DMBA-induced mammary tumors and some are similar to those previously reported in ACI rat model for estradiol-induced mammary tumors. The later group of changes is more interesting, since they may represent anomalies that involve genes with a critical role in mammary tumor development. Genetic

  19. Steroid receptor coactivators, HER-2 and HER-3 expression is stimulated by tamoxifen treatment in DMBA-induced breast cancer

    International Nuclear Information System (INIS)

    Moi, Line L Haugan; Flågeng, Marianne Hauglid; Gjerde, Jennifer; Madsen, Andre; Røst, Therese Halvorsen; Gudbrandsen, Oddrun Anita; Lien, Ernst A; Mellgren, Gunnar

    2012-01-01

    Steroid receptor coactivators (SRCs) may modulate estrogen receptor (ER) activity and the response to endocrine treatment in breast cancer, in part through interaction with growth factor receptor signaling pathways. In the present study the effects of tamoxifen treatment on the expression of SRCs and human epidermal growth factor receptors (HERs) were examined in an animal model of ER positive breast cancer. Sprague-Dawley rats with DMBA-induced breast cancer were randomized to 14 days of oral tamoxifen 40 mg/kg bodyweight/day or vehicle only (controls). Tumors were measured throughout the study period. Blood samples and tumor tissue were collected at sacrifice and tamoxifen and its main metabolites were quantified using LC-MS/MS. The gene expression in tumor of SRC-1, SRC-2/transcription intermediary factor-2 (TIF-2), SRC-3/amplified in breast cancer 1 (AIB1), ER, HER-1, -2, -3 and HER-4, as well as the transcription factor Ets-2, was measured by real-time RT-PCR. Protein levels were further assessed by Western blotting. Tamoxifen and its main metabolites were detected at high concentrations in serum and accumulated in tumor tissue in up to tenfolds the concentration in serum. Mean tumor volume/rat decreased in the tamoxifen treated group, but continued to increase in controls. The mRNA expression levels of SRC-1 (P = 0.035), SRC-2/TIF-2 (P = 0.002), HER-2 (P = 0.035) and HER-3 (P = 0.006) were significantly higher in tamoxifen treated tumors compared to controls, and the results were confirmed at the protein level using Western blotting. SRC-3/AIB1 protein was also higher in tamoxifen treated tumors. SRC-1 and SRC-2/TIF-2 mRNA levels were positively correlated with each other and with HER-2 (P ≤ 0.001), and the HER-2 mRNA expression correlated with the levels of the other three HER family members (P < 0.05). Furthermore, SRC-3/AIB1 and HER-4 were positively correlated with each other and Ets-2 (P < 0.001). The expression of SRCs and HER-2 and -3 is stimulated

  20. Effects of chemical carcinogens of hemopoiesis, immunopoiesis and viral oncogenesis. Technical progress report, December 1, 1977--September 30, 1978. [Mechanisms of potentiation of viral leukemogenesis by MMS, benzopyrene, and DMBA

    Energy Technology Data Exchange (ETDEWEB)

    OKunewick, J.P.; Raikow, R.B.; Meredith, R.F.

    1978-10-01

    During the past year we have concentrated on defining the circumstances under which methyl methanesulfonate (MMS), benzo(a) pyrene (BP), and 7,12-dimethylbenz(a)anthracene (DMBA) interact with Friend virus (FLV) to produce leukemia. The optimum scheduling for each and also the effective dose levels of the chemicals have been partially determined. There are at least three critical factors which govern whether or not a leukemogenic interaction can be shown between the chemical agents and the virus. These are chemical dose, virus dose, and their relative time of administration. The most critical of these is virus dose. The optimum virus dose is that which results in between 25 and 40% incidence of leukemia within 40 days after virus infection when virus is given alone. The chemical carcinogens have a lower dose threshold, below which no significant potentiating effect can be observed. The only upper limit would appear to be acute drug toxicity. The third element, timing, is equally critical and varies according to the chemical. This variation may reflect different mechanisms of action by the chemical agents and/or different pharmacology. Data on the effects of MMS, BP, and DMBA on the immune system have indicated that the viral enhancement is probably not dependent on this function. Further enhancement of the potentiation of viral leukemogenesis was observed using benzo(a)pyrene and caffeine, indicating that the inhibition by caffeine of DNA repair may be an important factor in virus potentiation. (ERB)

  1. Radiation-induced carcinogenesis: mechanistically based differences between gamma-rays and neutrons, and interactions with DMBA.

    Directory of Open Access Journals (Sweden)

    Igor Shuryak

    Full Text Available Different types of ionizing radiation produce different dependences of cancer risk on radiation dose/dose rate. Sparsely ionizing radiation (e.g. γ-rays generally produces linear or upwardly curving dose responses at low doses, and the risk decreases when the dose rate is reduced (direct dose rate effect. Densely ionizing radiation (e.g. neutrons often produces downwardly curving dose responses, where the risk initially grows with dose, but eventually stabilizes or decreases. When the dose rate is reduced, the risk increases (inverse dose rate effect. These qualitative differences suggest qualitative differences in carcinogenesis mechanisms. We hypothesize that the dominant mechanism for induction of many solid cancers by sparsely ionizing radiation is initiation of stem cells to a pre-malignant state, but for densely ionizing radiation the dominant mechanism is radiation-bystander-effect mediated promotion of already pre-malignant cell clone growth. Here we present a mathematical model based on these assumptions and test it using data on the incidence of dysplastic growths and tumors in the mammary glands of mice exposed to high or low dose rates of γ-rays and neutrons, either with or without pre-treatment with the chemical carcinogen 7,12-dimethylbenz-alpha-anthracene (DMBA. The model provides a mechanistic and quantitative explanation which is consistent with the data and may provide useful insight into human carcinogenesis.

  2. The Role of Dietary Extra Virgin Olive Oil and Corn Oil on the Alteration of Epigenetic Patterns in the Rat DMBA-Induced Breast Cancer Model.

    Directory of Open Access Journals (Sweden)

    Cristina Rodríguez-Miguel

    Full Text Available Disruption of epigenetic patterns is a major change occurring in all types of cancers. Such alterations are characterized by global DNA hypomethylation, gene-promoter hypermethylation and aberrant histone modifications, and may be modified by environment. Nutritional factors, and especially dietary lipids, have a role in the etiology of breast cancer. Thus, we aimed to analyze the influence of different high fat diets on DNA methylation and histone modifications in the rat dimethylbenz(aanthracene (DMBA-induced breast cancer model. Female Sprague-Dawley rats were fed a low-fat, a high corn-oil or a high extra-virgin olive oil (EVOO diet from weaning or from induction with DMBA. In mammary glands and tumors we analyzed global and gene specific (RASSF1A, TIMP3 DNA methylation by LUMA and bisulfite pyrosequencing assays, respectively. We also determined gene expression and enzymatic activity of DNA methyltransferases (DNMT1, DNMT3a and DNMT3b and evaluated changes in histone modifications (H3K4me2, H3K27me3, H4K20me3 and H4K16ac by western-blot. Our results showed variations along time in the global DNA methylation of the mammary gland displaying decreases at puberty and with aging. The olive oil-enriched diet, on the one hand, increased the levels of global DNA methylation in mammary gland and tumor, and on the other, changed histone modifications patterns. The corn oil-enriched diet increased DNA methyltransferase activity in both tissues, resulting in an increase in the promoter methylation of the tumor suppressor genes RASSF1A and TIMP3. These results suggest a differential effect of the high fat diets on epigenetic patterns with a relevant role in the neoplastic transformation, which could be one of the mechanisms of their differential promoter effect, clearly stimulating for the high corn-oil diet and with a weaker influence for the high EVOO diet, on breast cancer progression.

  3. The potential of shark bone powder in breast cancer inhibition (pre-clinical study in DMBA-Induced Sprague Dawly Rats)

    Science.gov (United States)

    Bintari, S. H.; Parman, S.; Dafip, M.

    2018-03-01

    Breast cancer is a malignant disease, which lead to second cause of that after cervical cancer in women. To date, lots of drugs and supplement have been developed and consumed by patients. Shark bone is one of the supplements that might inhibit the proliferation of cancer cells. The application of shark bone powder for supplementation in breast cancer cases still becomes controversy; but until now people are still many who consume as a supplement. This study aimed to prove the potency of shark bone powder in the inhibition of breast cancer proliferation and to propose the possibility of its biological mechanism. The pre-clinical experimental study used a controlled posttest controlled design with 25 white rats strains of DML-induced Sprague-Dawley strains. The cancer markers observed were p53, AgNORs, VEGF, Bcl-2, and Cas-3. The test subjects were divided into 3 groups: control group and 2 treatment groups fed modified with 60% and 90% respectively. A pre-clinical trial of shark bone powder showed that there was significant inhibition for the DMBA-induced anti proliferation and breast cell cancer (p breast cancer proliferation lies in concentration 30mg/BB/day.

  4. 7,12-Dimethylbenzanthracene induces apoptosis in RL95-2 human endometrial cancer cells: Ligand-selective activation of cytochrome P450 1B1

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ji Young [Department of Anatomy and Cell Biology, College of Medicine, Dong-A University, Busan 602-714 (Korea, Republic of); Medical Research Science Center, Dong-A University, Busan 602-714 (Korea, Republic of); Lee, Seung Gee [Department of Anatomy and Cell Biology, College of Medicine, Dong-A University, Busan 602-714 (Korea, Republic of); Mitochondria Hub Regulation Center, Dong-A University, Busan 602-714 (Korea, Republic of); Chung, Jin-Yong [Department of Anatomy and Cell Biology, College of Medicine, Dong-A University, Busan 602-714 (Korea, Republic of); Medical Research Science Center, Dong-A University, Busan 602-714 (Korea, Republic of); Kim, Yoon-Jae [Department of Anatomy and Cell Biology, College of Medicine, Dong-A University, Busan 602-714 (Korea, Republic of); Mitochondria Hub Regulation Center, Dong-A University, Busan 602-714 (Korea, Republic of); Park, Ji-Eun [Department of Anatomy and Cell Biology, College of Medicine, Dong-A University, Busan 602-714 (Korea, Republic of); Medical Research Science Center, Dong-A University, Busan 602-714 (Korea, Republic of); Oh, Seunghoon [Department of Physiology, College of Medicine, Dankook University, Cheonan 330-714 (Korea, Republic of); Lee, Se Yong [Department of Obstetrics and Gynecology, Busan Medical Center, Busan 611-072 (Korea, Republic of); Choi, Hong Jo [Department of General Surgery, College of Medicine, Dong-A University, Busan 602-714 (Korea, Republic of); Yoo, Young Hyun, E-mail: yhyoo@dau.ac.kr [Department of Anatomy and Cell Biology, College of Medicine, Dong-A University, Busan 602-714 (Korea, Republic of); Mitochondria Hub Regulation Center, Dong-A University, Busan 602-714 (Korea, Republic of); Medical Research Science Center, Dong-A University, Busan 602-714 (Korea, Republic of); and others

    2012-04-15

    7,12-Dimethylbenzanthracene (DMBA), a polycyclic aromatic hydrocarbon, exhibits mutagenic, carcinogenic, immunosuppressive, and apoptogenic properties in various cell types. To achieve these functions effectively, DMBA is modified to its active form by cytochrome P450 1 (CYP1). Exposure to DMBA causes cytotoxicity-mediated apoptosis in bone marrow B cells and ovarian cells. Although uterine endometrium constitutively expresses CYP1A1 and CYP1B1, their apoptotic role after exposure to DMBA remains to be elucidated. Therefore, we chose RL95-2 endometrial cancer cells as a model system for studying DMBA-induced cytotoxicity and cell death and hypothesized that exposure to DMBA causes apoptosis in this cell type following CYP1A1 and/or CYP1B1 activation. We showed that DMBA-induced apoptosis in RL95-2 cells is associated with activation of caspases. In addition, mitochondrial changes, including decrease in mitochondrial potential and release of mitochondrial cytochrome c into the cytosol, support the hypothesis that a mitochondrial pathway is involved in DMBA-induced apoptosis. Exposure to DMBA upregulated the expression of AhR, Arnt, CYP1A1, and CYP1B1 significantly; this may be necessary for the conversion of DMBA to DMBA-3,4-diol-1,2-epoxide (DMBA-DE). Although both CYP1A1 and CYP1B1 were significantly upregulated by DMBA, only CYP1B1 exhibited activity. Moreover, knockdown of CYP1B1 abolished DMBA-induced apoptosis in RL95-2 cells. Our data show that RL95-2 cells are susceptible to apoptosis by exposure to DMBA and that CYP1B1 plays a pivotal role in DMBA-induced apoptosis in this system. -- Highlights: ► Cytotoxicity-mediated apoptogenic action of DMBA in human endometrial cancer cells. ► Mitochondrial pathway in DMBA-induced apoptosis of RL95-2 endometrial cancer cells. ► Requirement of ligand-selective activation of CYP1B1 in DMBA-induced apoptosis.

  5. Modulating effect of dimethylbenzanthracene on gamma-ray mutagenesis in the soybean test system

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, T. [National Inst. of Genetics, Mishima, Shizuoka (Japan); Inoue, T.

    1987-10-15

    Dimethylbenzanthracene (DMBA), a strong tumor initiator, did not show mutagenic activity in the soybean test system either alone or in combination with tumor promoter, TPA. In combination treatments with DMBA and gamma-rays, the mutagenicity of gamma-rays was not affected by post-treatment with DMBA. However, DMBA pre-treatment clearly reduced gammaray-ray induced spotting frequency, suggesting that DMBA affects mutagenesis in gamma-irradiated soybean cells.

  6. Acute 7,12-dimethylbenz[a]anthracene exposure causes differential concentration-dependent follicle depletion and gene expression in neonatal rat ovaries

    Energy Technology Data Exchange (ETDEWEB)

    Madden, Jill A. [Department of Animal Science, Iowa State University, Ames, IA 50011 (United States); Hoyer, Patricia B. [Department of Physiology, University of Arizona, Tucson, AZ 85724 (United States); Devine, Patrick J. [INRS—Institut Armand-Frappier Research Centre, University of Quebec, Laval, QC H7V 1B7 (Canada); Keating, Aileen F., E-mail: akeating@iastate.edu [Department of Animal Science, Iowa State University, Ames, IA 50011 (United States); Department of Physiology, University of Arizona, Tucson, AZ 85724 (United States)

    2014-05-01

    Chronic exposure to the polycyclic aromatic hydrocarbon 7,12-dimethylbenz[a]anthracene (DMBA), generated during combustion of organic matter including cigarette smoke, depletes all ovarian follicle types in the mouse and rat, and in vitro models mimic this effect. To investigate the mechanisms involved in follicular depletion during acute DMBA exposure, two concentrations of DMBA at which follicle depletion has (75 nM) and has not (12.5 nM) been observed were investigated. Postnatal day four F344 rat ovaries were maintained in culture for four days before a single exposure to vehicle control (1% DMSO; CT) or DMBA (12 nM; low-concentration or 75 nM; high-concentration). After four or eight additional days of culture, DMBA-induced follicle depletion was evaluated via follicle enumeration. Relative to control, DMBA did not affect follicle numbers after 4 days of exposure, but induced large primary follicle loss at both concentrations after 8 days; while, the low-concentration DMBA also caused secondary follicle depletion. Neither concentration affected primordial or small primary follicle number. RNA was isolated and quantitative RT-PCR performed prior to follicle loss to measure mRNA levels of genes involved in xenobiotic metabolism (Cyp2e1, Gstmu, Gstpi, Ephx1), autophagy (Atg7, Becn1), oxidative stress response (Sod1, Sod2) and the phosphatidylinositol 3-kinase (PI3K) pathway (Kitlg, cKit, Akt1) 1, 2 and 4 days after exposure. With the exception of Atg7 and cKit, DMBA increased (P < 0.05) expression of all genes investigated. Also, BECN1 and pAKT{sup Thr308} protein levels were increased while cKIT was decreased by DMBA exposure. Taken together, these results suggest an increase in DMBA bioactivation, add to the mechanistic understanding of DMBA-induced ovotoxicity and raise concern regarding female low concentration DMBA exposures. - Highlights: • Acute DMBA exposures induce large primary and/or secondary follicle loss. • Acute DMBA exposure did not impact

  7. Acute 7,12-dimethylbenz[a]anthracene exposure causes differential concentration-dependent follicle depletion and gene expression in neonatal rat ovaries

    International Nuclear Information System (INIS)

    Madden, Jill A.; Hoyer, Patricia B.; Devine, Patrick J.; Keating, Aileen F.

    2014-01-01

    Chronic exposure to the polycyclic aromatic hydrocarbon 7,12-dimethylbenz[a]anthracene (DMBA), generated during combustion of organic matter including cigarette smoke, depletes all ovarian follicle types in the mouse and rat, and in vitro models mimic this effect. To investigate the mechanisms involved in follicular depletion during acute DMBA exposure, two concentrations of DMBA at which follicle depletion has (75 nM) and has not (12.5 nM) been observed were investigated. Postnatal day four F344 rat ovaries were maintained in culture for four days before a single exposure to vehicle control (1% DMSO; CT) or DMBA (12 nM; low-concentration or 75 nM; high-concentration). After four or eight additional days of culture, DMBA-induced follicle depletion was evaluated via follicle enumeration. Relative to control, DMBA did not affect follicle numbers after 4 days of exposure, but induced large primary follicle loss at both concentrations after 8 days; while, the low-concentration DMBA also caused secondary follicle depletion. Neither concentration affected primordial or small primary follicle number. RNA was isolated and quantitative RT-PCR performed prior to follicle loss to measure mRNA levels of genes involved in xenobiotic metabolism (Cyp2e1, Gstmu, Gstpi, Ephx1), autophagy (Atg7, Becn1), oxidative stress response (Sod1, Sod2) and the phosphatidylinositol 3-kinase (PI3K) pathway (Kitlg, cKit, Akt1) 1, 2 and 4 days after exposure. With the exception of Atg7 and cKit, DMBA increased (P < 0.05) expression of all genes investigated. Also, BECN1 and pAKT Thr308 protein levels were increased while cKIT was decreased by DMBA exposure. Taken together, these results suggest an increase in DMBA bioactivation, add to the mechanistic understanding of DMBA-induced ovotoxicity and raise concern regarding female low concentration DMBA exposures. - Highlights: • Acute DMBA exposures induce large primary and/or secondary follicle loss. • Acute DMBA exposure did not impact

  8. The effects of combination of Eurycoma longifolia Jack ethanolic extract and doxorubicine on hematological profile in rats given by 7,12-dimethylbenz(a)anthracene

    Science.gov (United States)

    Nurani, L. H.; Mursyidi, A.; Widyarini, S.; Rohman, A.

    2017-11-01

    Doxorubicin (Dox) is known as anticancer drug commonly used for cancer treatment. Eurycoma longifolia Jack or Pasakbumi was reported to have chemopreventive effect. In cancer patients, there are some dysfunctions of blood parameter, therefore some hematologic tests are needed to monitor cancer patients. In this study, the effects of combination of ethanolic extract of E. longifolia Jack (EEE) and Dox on hematologic profiles were investigated in rats injected by DMBA. Rats were divided into eight groups. Group I was normal group; Group II, rats were treated with extract dose 100 mg/kgbw; Groups III, IV, V, VI, VII and VIII, rats were treated with Dox, DMBA, DMBA+Dox, DMBA+EEE, DMBA+Dox +EEE, and Dox+EEE, respectively. DMBA administration orally was conducted twice a week for 5 weeks. At 16th week of treatments, bloods were taken from orbitalis sinus for hematologicals profile (levels of Hb, erytrocyte, hematocrite, leukocyte, MCV, MCH, and differencial leucocyte count) measurements. These data were analyzed by one way ANOVA followed by LSD test. DMBA administration significantly decreased the hematological profiles compared to the normal group, except in lymphocyte level. Rats treated with extract and extract+Dox were able to increase the hematological profile compared to rats given by DMBA only. Based on these findings it can be concluded that the combination of EEE and Dox potentially increase hematological profile of rats given by DMBA.

  9. 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.

  10. Ganoderma lucidum total triterpenes induce apoptosis in MCF-7 cells and attenuate DMBA induced mammary and skin carcinomas in experimental animals.

    Science.gov (United States)

    Smina, T P; Nitha, B; Devasagayam, T P A; Janardhanan, K K

    2017-01-01

    Ganoderma lucidum total triterpenes were evaluated for its apoptosis-inducing and anti-cancer activities. Cytotoxicity and pro-apoptotic effect of total triterpenes were evaluated in human breast adenocarcinoma (MCF-7) cell line using MTT assay and DNA fragmentation analysis. Total triterpenes induced apoptosis in MCF-7 cells by down-regulating the levels of cyclin D1, Bcl-2, Bcl-xL and also by up-regulating the levels of Bax and caspase-9. Anti-carcinogenicity of total triterpenes was analysed using dimethyl benz [a] anthracene (DMBA) induced skin papilloma and mammary adenocarcinoma in Swiss albino mice and Wistar rats respectively. Topical application of 5mg, 10mg and 20mg total triterpenes reduced the incidence of skin papilloma by 62.5, 37.5 and 12.5% respectively. Incidence of the mammary tumour was also reduced significantly by 33.33, 66.67 and 16.67% in 10, 50 and 100mg/kg b.wt. total triterpenes treated animals respectively. Total triterpenes were also found to reduce the average number of tumours per animal and extended the tumour latency period in both the models. The results indicate the potential cytotoxicity and anti-cancerous activity of total triterpenes, there by opens up a path to the development of a safe and successive chemo preventive agent of natural origin. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Study on combined effects of radiation and bleomycin on carcinoma of tongue iduced by DMBA in hamster

    International Nuclear Information System (INIS)

    Kitamura, Nobuyasu

    1979-01-01

    Carcinoma of the tongue (Mostly squamous cell carcinoma) was induced in hamsters by 9,10-dimethyl-1, 2-benzanthracene (DMBA). The amount of various kinds of free radicals, which increased due to radioactive radiation and administration of bleomycin (BLM) in tongue and liver tissues, was determined by an electron spin resonance method. The hamsters were separated into seven groups: BLM administration only (group A 1 ), 60 Co-γ-ray irradiation only (A 2 ), 60 Co-γ-ray irradiation 30 min after BLM administration (A 3 ), BLM administration 30 min after 60 Co-γ-ray irradiation (A 4 ), 60 Co-γ-ray irradiation 24 h after BLM administration (A 5 ), BLM administration 24 h after 60 Co-γ-ray irradiation (A 6 ), and the control (A 7 ). Mean free radicals in the groups were compared, using samples fixed 5 min after treatment. The ratio of mean free radicals of carcinoma of the tongue were 2.6, 2.9, 3.7, 3.9, 3.0, 3.2, and 1 in A 1 , A 2 , A 3 , A 4 , A 5 , A 6 , and A 7 . The ratio of mean free radicals of the liver under the same condition were 1.5, 1.6, 3.3, 3.8, 2.2, 2.6, and 1. A combination of BLM and radioactive radiation increased the amount of free radicals in carcinoma of the tongue and in the liver. Especially BLM administration 30 min after 60 Co-γ-ray irradiation showed a synergistic effect. Judging from the amount of free radicals determined, the effect of radioactive irradiation increased when combined with BLM administration. BLM was most effective when it was administered 5 min after radioactive irradiation. (Tsunoda, M.)

  12. Protective role for ovarian glutathione S-transferase isoform pi during 7,12-dimethylbenz[a]anthracene-induced ovotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Poulomi, E-mail: poulomib@iastate.edu; Keating, Aileen F., E-mail: akeating@iastate.edu

    2012-04-15

    7,12-Dimethylbenz[a]anthracene (DMBA) destroys ovarian follicles at all developmental stages. This study investigated a role for the glutathione S-transferase (Gst) isoforms alpha (a), mu (m) and pi (p) and the transcription factors, Ahr and Nrf2, during DMBA-induced ovotoxicity, and their regulation by phosphatidylinositol-3 kinase (PI3K) signaling. Negative regulation of JNK by GSTP during DMBA exposure was also studied. Post-natal day (PND) 4 Fischer 344 rat ovaries were exposed to vehicle control (1% DMSO) ± DMBA (1 μM) or vehicle control (1% DMSO) ± LY294002 (PI3K inhibitor; 20 μM) for 1, 2, 4, or 6 days. Total RNA or protein was isolated, followed by RT-PCR or Western blotting to determine mRNA or protein level, respectively. Immunoprecipitation using an anti-GSTP antibody was performed to determine interaction between GSTP and JNK, followed by Western blotting to determine JNK and p-c-Jun protein level. DMBA had no impact on Gsta, Gstm or Nrf2 mRNA level, but increased Gstp mRNA and protein after 2 days. Ahr mRNA and protein increased after 2 and 4 days of DMBA exposure, respectively and DMBA increased NRF2 protein level after 4 days. JNK bound to GSTP was increased during DMBA exposure, with a concomitant decrease in unbound JNK and p-c-Jun. Ahr and Gstp mRNA were decreased (2 days) and increased (4 days) by PI3K inhibition, while Gstm mRNA increased (P < 0.05) after both time points, and there was no effect on Nrf2 mRNA. PI3K inhibition increased AHR, NRF2 and GSTP protein level. These findings support involvement of ovarian GSTP during DMBA exposure, and indicate a regulatory role for the PI3K signaling pathway on ovarian xenobiotic metabolism gene expression. -- Highlights: ► Ovarian GSTP is activated in response to DMBA exposure. ► AhR and Nrf2 transcription factors are up-regulated by DMBA. ► PI3K signaling regulates Ahr, Nrf2 and Gstp expression. ► GSTP negatively regulates ovarian JNK in response to DMBA exposure.

  13. 7,12-Dimethylbenz[a]anthracene-Induced Malignancies in a Mouse Model of Menopause

    Science.gov (United States)

    Marion, Samuel L; Watson, Jennifer; Sen, Nivedita; Brewer, Molly A; Barton, Jennifer K; Hoyer, Patricia B

    2013-01-01

    Ovarian cancer has a high mortality rate because there are few symptoms in early disease development. The incidence of ovarian cancer increases in women after menopause. Understanding early events in this disease can best be achieved by using animal models. Therefore, the objective of this study was to develop and track the onset of ovarian tumorigenesis in mice mimicking characteristics of postmenopausal epithelial cancer in women. Female B6C3F1 mice (age, 28 d) received 4-vinylcyclohexene diepoxide (VCD, 160 mg/kg IV daily for 20 d) to cause ovarian failure. Four months after VCD treatment, via surgical intervention, each mouse received a single injection of 7,12-dimethylbenz[a]anthracene (DMBA) or vehicle control (sesame oil) under the bursa of the right ovary to cause ovarian neoplasms. The experimental groups were untreated controls (Con–Con), DMBA-treatment only (Con–DMBA), VCD treatment only (VCD–Con), and VCD+DMBA-treated (VCD+DMBA) mice. At 3, 5, 7, and 9 mo after DMBA injection, ovaries were collected for histologic and immunohistochemical evaluation. No tumors developed in Con–Con mice. All VCD-treated mice (with or without DMBA) exhibited ovarian failure. Mice that received both VCD and DMBA exhibited tumors at 3 mo (50%), 5 mo (14%), 7 mo (90%), and 9 mo (57%) after DMBA treatment; 31% of the tumors were epithelial in origin. Our findings confirm that inducing ovarian tumors in mice by chemical means is an effective method for studying early stages of tumor development that may be relevant to epithelial ovarian cancers that arise in postmenopausal women. PMID:23561932

  14. Formation of 7-hydroxymethyl-12-methylbenz(a)anthracene-DNA adducts from 7,12-dimethylbenz(a)anthracene in mouse epidermis

    International Nuclear Information System (INIS)

    DiGiovanni, J.; Nebzydoski, A.P.; Decina, P.C.

    1983-01-01

    The formation of DNA adducts from [ 3 H]-7-hydroxymethyl-12-methylbenz(a)anthracene (7-OHM-12-MBA) and [ 3 H]-7,12-dimethylbenz(a)anthracene (DMBA) in the epidermis of Sencar mice was analyzed. Comparison of Sephadex LH-20 chromatographic profiles of DNA samples isolated from mice treated with DMBA or 7-OHM-12-MBA suggested that the DMBA-treated animals contained DNA adduct(s) derived from the further metabolism of 7-OHM-12-MBA. Further analysis of DNA samples from DMBA-treated mice by high-pressure liquid chromatography demonstrated the presence of 5 DNA adducts which were chromatographically indistinguishable from the DNA adducts formed in 7-OHM-12-MBA-treated mice. Epidermal homogenates were utilized to catalyze the covalent binding of [ 3 H]DMBA and [ 3 H]-7-OHM-12-MBA to calf thymus DNA in vitro. Under conditions of limiting concentrations of [ 3 H]DMBA, the majority of the DNA adducts formed chromatographed in regions where 7-OHM-12-MBA-DNA adducts eluted. A major DMBA-DNA adduct formed in this in vitro system eluted with the same retention time as did the major 7-OHM-12-MBA-DNA adduct formed in mouse skin in vivo. These results when coupled with the in vivo data suggest that 7-OHM-12-MBA is an intermediate for at least some of the binding of DMBA to epidermal DNA in Sencar mice

  15. Enhanced susceptibility of ovaries from obese mice to 7,12-dimethylbenz[a]anthracene-induced DNA damage

    International Nuclear Information System (INIS)

    Ganesan, Shanthi; Nteeba, Jackson; Keating, Aileen F.

    2014-01-01

    7,12-Dimethylbenz[a]anthracene (DMBA) depletes ovarian follicles and induces DNA damage in extra-ovarian tissues, thus, we investigated ovarian DMBA-induced DNA damage. Additionally, since obesity is associated with increased offspring birth defect incidence, we hypothesized that a DMBA-induced DNA damage response (DDR) is compromised in ovaries from obese females. Wild type (lean) non agouti (a/a) and KK.Cg-Ay/J heterozygote (obese) mice were dosed with sesame oil or DMBA (1 mg/kg; intraperitoneal injection) at 18 weeks of age, for 14 days. Total ovarian RNA and protein were isolated and abundance of Ataxia telangiectasia mutated (Atm), X-ray repair complementing defective repair in Chinese hamster cells 6 (Xrcc6), breast cancer type 1 (Brca1), Rad 51 homolog (Rad51), poly [ADP-ribose] polymerase 1 (Parp1) and protein kinase, DNA-activated, catalytic polypeptide (Prkdc) were quantified by RT-PCR or Western blot. Phosphorylated histone H2AX (γH2AX) level was determined by Western blotting. Obesity decreased (P < 0.05) basal protein abundance of PRKDC and BRCA1 proteins but increased (P < 0.05) γH2AX and PARP1 proteins. Ovarian ATM, XRCC6, PRKDC, RAD51 and PARP1 proteins were increased (P < 0.05) by DMBA exposure in lean mice. A blunted DMBA-induced increase (P < 0.05) in XRCC6, PRKDC, RAD51 and BRCA1 was observed in ovaries from obese mice, relative to lean counterparts. Taken together, DMBA exposure induced γH2AX as well as the ovarian DDR, supporting that DMBA causes ovarian DNA damage. Additionally, ovarian DDR was partially attenuated in obese females raising concern that obesity may be an additive factor during chemical-induced ovotoxicity. - Highlights: • DMBA induces markers of ovarian DNA damage. • Obesity induces low level ovarian DNA damage. • DMBA-induced DNA repair response is altered by obesity

  16. Enhanced susceptibility of ovaries from obese mice to 7,12-dimethylbenz[a]anthracene-induced DNA damage

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, Shanthi, E-mail: shanthig@iastate.edu; Nteeba, Jackson, E-mail: nteeba@iastate.edu; Keating, Aileen F., E-mail: akeating@iastate.edu

    2014-12-01

    7,12-Dimethylbenz[a]anthracene (DMBA) depletes ovarian follicles and induces DNA damage in extra-ovarian tissues, thus, we investigated ovarian DMBA-induced DNA damage. Additionally, since obesity is associated with increased offspring birth defect incidence, we hypothesized that a DMBA-induced DNA damage response (DDR) is compromised in ovaries from obese females. Wild type (lean) non agouti (a/a) and KK.Cg-Ay/J heterozygote (obese) mice were dosed with sesame oil or DMBA (1 mg/kg; intraperitoneal injection) at 18 weeks of age, for 14 days. Total ovarian RNA and protein were isolated and abundance of Ataxia telangiectasia mutated (Atm), X-ray repair complementing defective repair in Chinese hamster cells 6 (Xrcc6), breast cancer type 1 (Brca1), Rad 51 homolog (Rad51), poly [ADP-ribose] polymerase 1 (Parp1) and protein kinase, DNA-activated, catalytic polypeptide (Prkdc) were quantified by RT-PCR or Western blot. Phosphorylated histone H2AX (γH2AX) level was determined by Western blotting. Obesity decreased (P < 0.05) basal protein abundance of PRKDC and BRCA1 proteins but increased (P < 0.05) γH2AX and PARP1 proteins. Ovarian ATM, XRCC6, PRKDC, RAD51 and PARP1 proteins were increased (P < 0.05) by DMBA exposure in lean mice. A blunted DMBA-induced increase (P < 0.05) in XRCC6, PRKDC, RAD51 and BRCA1 was observed in ovaries from obese mice, relative to lean counterparts. Taken together, DMBA exposure induced γH2AX as well as the ovarian DDR, supporting that DMBA causes ovarian DNA damage. Additionally, ovarian DDR was partially attenuated in obese females raising concern that obesity may be an additive factor during chemical-induced ovotoxicity. - Highlights: • DMBA induces markers of ovarian DNA damage. • Obesity induces low level ovarian DNA damage. • DMBA-induced DNA repair response is altered by obesity.

  17. Impact of 7,12-dimethylbenz[a]anthracene exposure on connexin gap junction proteins in cultured rat ovaries

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, Shanthi, E-mail: shanthig@iastate.edu; Keating, Aileen F., E-mail: akeating@iastate.edu

    2014-01-15

    7,12-Dimethylbenz[a]anthracene (DMBA) destroys ovarian follicles in a concentration-dependent manner. The impact of DMBA on connexin (CX) proteins that mediate communication between follicular cell types along with pro-apoptotic factors p53 and Bax were investigated. Postnatal day (PND) 4 Fisher 344 rat ovaries were cultured for 4 days in vehicle medium (1% DMSO) followed by a single exposure to vehicle control (1% DMSO) or DMBA (12.5 nM or 75 nM) and cultured for 4 or 8 days. RT-PCR was performed to quantify Cx37, Cx43, p53 and Bax mRNA level. Western blotting and immunofluorescence staining were performed to determine CX37 or CX43 level and/or localization. Cx37 mRNA and protein increased (P < 0.05) at 4 days of 12.5 nM DMBA exposure. Relative to vehicle control-treated ovaries, mRNA encoding Cx43 decreased (P < 0.05) but CX43 protein increased (P < 0.05) at 4 days by both DMBA exposures. mRNA expression of pro-apoptotic p53 was decreased (P < 0.05) but no changes in Bax expression were observed after 4 days of DMBA exposures. In contrast, after 8 days, DMBA decreased Cx37 and Cx43 mRNA and protein but increased both p53 and Bax mRNA levels. CX43 protein was located between granulosa cells, while CX37 was located at the oocyte cell surface of all follicle stages. These findings support that DMBA exposure impacts ovarian Cx37 and Cx43 mRNA and protein prior to both observed changes in pro-apoptotic p53 and Bax and follicle loss. It is possible that such interference in follicular cell communication is detrimental to follicle viability, and may play a role in DMBA-induced follicular atresia. - Highlights: • DMBA increases Cx37 and Cx43 expression prior to follicle loss. • During follicle loss both Cx37 and Cx43 expressions are reduced. • CX43 protein is absent in follicle remnants lacking an oocyte.

  18. Effect of phosphatidylinositol-3 kinase inhibition on ovotoxicity caused by 4-vinylcyclohexene diepoxide and 7, 12-dimethylbenz[a]anthracene in neonatal rat ovaries

    International Nuclear Information System (INIS)

    Keating, Aileen F.; Mark, Connie J.; Sen, Nivedita; Sipes, I. Glenn; Hoyer, Patricia B.

    2009-01-01

    4-vinylcyclohexene diepoxide (VCD) is an ovotoxicant that specifically destroys primordial and small primary follicles in the ovaries of mice and rats. In contrast, 7,12-dimethylbenz[a]anthracene (DMBA) is ovotoxic to all ovarian follicle classes. This study investigated phosphatidylinositol-3 kinase signaling involvement in VCD- and DMBA-induced ovotoxicity. Postnatal day (PND) 4 Fischer 344 (F344) rat whole ovaries were cultured for 2-12 days in vehicle control, VCD (30 μM), or DMBA (1 μM), ± PI3 kinase inhibitor LY294002 (20 μM) or its inactive analog LY303511 (20 μM). Following culture, ovaries were histologically evaluated, and healthy follicles were classified and counted. PI3 kinase inhibition had no effect on primordial follicle number, but reduced (P 0.05) at any time, but did cause loss (P < 0.05) of small primary follicles. DMBA exposure caused primordial and small primary follicle loss (P < 0.05) on day 6. Further, DMBA-induced primordial and small primary follicle loss was greater with PI3 kinase inhibition (P < 0.05) than with DMBA alone. These results support that (1) PI3 kinase mediates primordial to small primary follicle recruitment, (2) VCD, but not DMBA, enhances ovotoxicity by increasing primordial to small primary follicle recruitment, and (3) in addition to xenobiotic-induced ovotoxicity, VCD is also a useful model chemical with which to elucidate signaling mechanisms involved in primordial follicle recruitment.

  19. Metabolism of benzo[a]pyrene and 7,12-dimethylbenz[a]anthracene in cultured human fetal aortic smooth muscle cells

    International Nuclear Information System (INIS)

    Bond, J.A.; Kocan, R.M.; Benditt, E.P.; Juchau, M.R.

    1979-01-01

    Cultured human fetal aortic smooth muscle cells derived from the abdominal aorta converted benzo[a]pyrene (BaP) and 7,12-dimethylbenz[a]anthracene (DMBA) via cytochrome P-450-dependent monooxygenation to metabolites detectable by both a highly sensitive radiometric assay and high pressure liquid chromatography (HPLC). Cells incubated with 3 H-BaP transformed this substrate primarily to phenols. 14 C-DMBA was converted to metabolites that cochromatographed with 12-hydroxymethyl-methylbenz[a]anthracene, 7-hydroxymethyl-12-methylbenz[a]anthracene, 7- 7,12-dihydroxymethylbenz[a]anthracene, and trans-8,9-dihydrodiol-7,12-DMBA. Exposure of cells in culture to 13 μM 1,2-benz[a]anthracene resulted in increased oxidative metabolism of both BaP and DMBA. In the case of BaP, total phenol formation was increased, while with DMBA all metabolites detected by HPLC were increased. Support for the potential role of metabolism of polycyclic aromatic hydrocarbons by aortic smooth muscle cells in the etiology of atherosclerosis was obtained

  20. Impact of obesity on 7,12-dimethylbenz[a]anthracene-induced altered ovarian connexin gap junction proteins in female mice

    International Nuclear Information System (INIS)

    Ganesan, Shanthi; Nteeba, Jackson; Keating, Aileen F.

    2015-01-01

    The ovarian gap junction proteins alpha 4 (GJA4 or connexin 37; CX37), alpha 1 (GJA1 or connexin 43; CX43) and gamma 1 (GJC1 or connexin 45; CX45) are involved in cell communication and folliculogenesis. 7,12-dimethylbenz[a]anthracene (DMBA) alters Cx37 and Cx43 expression in cultured neonatal rat ovaries. Additionally, obesity has an additive effect on DMBA-induced ovarian cell death and follicle depletion, thus, we investigated in vivo impacts of obesity and DMBA on CX protein levels. Ovaries were collected from lean and obese mice aged 6, 12, 18, or 24 wks. A subset of 18 wk old mice (lean and obese) were dosed with sesame oil or DMBA (1 mg/kg; ip) for 14 days and ovaries collected 3 days thereafter. Cx43 and Cx45 mRNA and protein levels decreased (P < 0.05) after 18 wks while Cx37 mRNA and protein levels decreased (P < 0.05) after 24 wks in obese ovaries. Cx37 mRNA and antral follicle protein staining intensity were reduced (P < 0.05) by obesity while total CX37 protein was reduced (P < 0.05) in DMBA exposed obese ovaries. Cx43 mRNA and total protein levels were decreased (P < 0.05) by DMBA in both lean and obese ovaries while basal protein staining intensity was reduced (P < 0.05) in obese controls. Cx45 mRNA, total protein and protein staining intensity level were decreased (P < 0.05) by obesity. These data support that obesity temporally alters gap junction protein expression and that DMBA-induced ovotoxicity may involve reduced gap junction protein function. - Highlights: • Ovarian gap junction proteins are affected by ovarian aging and obesity. • DMBA exposure negatively impacts gap junction proteins. • Altered gap junction proteins may contribute to infertility

  1. Impact of obesity on 7,12-dimethylbenz[a]anthracene-induced altered ovarian connexin gap junction proteins in female mice

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, Shanthi, E-mail: shanthig@iastate.edu; Nteeba, Jackson, E-mail: nteeba@iastate.edu; Keating, Aileen F., E-mail: akeating@iastate.edu

    2015-01-01

    The ovarian gap junction proteins alpha 4 (GJA4 or connexin 37; CX37), alpha 1 (GJA1 or connexin 43; CX43) and gamma 1 (GJC1 or connexin 45; CX45) are involved in cell communication and folliculogenesis. 7,12-dimethylbenz[a]anthracene (DMBA) alters Cx37 and Cx43 expression in cultured neonatal rat ovaries. Additionally, obesity has an additive effect on DMBA-induced ovarian cell death and follicle depletion, thus, we investigated in vivo impacts of obesity and DMBA on CX protein levels. Ovaries were collected from lean and obese mice aged 6, 12, 18, or 24 wks. A subset of 18 wk old mice (lean and obese) were dosed with sesame oil or DMBA (1 mg/kg; ip) for 14 days and ovaries collected 3 days thereafter. Cx43 and Cx45 mRNA and protein levels decreased (P < 0.05) after 18 wks while Cx37 mRNA and protein levels decreased (P < 0.05) after 24 wks in obese ovaries. Cx37 mRNA and antral follicle protein staining intensity were reduced (P < 0.05) by obesity while total CX37 protein was reduced (P < 0.05) in DMBA exposed obese ovaries. Cx43 mRNA and total protein levels were decreased (P < 0.05) by DMBA in both lean and obese ovaries while basal protein staining intensity was reduced (P < 0.05) in obese controls. Cx45 mRNA, total protein and protein staining intensity level were decreased (P < 0.05) by obesity. These data support that obesity temporally alters gap junction protein expression and that DMBA-induced ovotoxicity may involve reduced gap junction protein function. - Highlights: • Ovarian gap junction proteins are affected by ovarian aging and obesity. • DMBA exposure negatively impacts gap junction proteins. • Altered gap junction proteins may contribute to infertility.

  2. Synergistic effect of lycopene and tocopherol against oxidative stress and mammary tumorigenesis induced by 7,12-dimethyl[a]benzanthracene in female rats.

    Science.gov (United States)

    Al-Malki, Abdulrahman L; Moselhy, Said S; Refai, Mohammed Y

    2012-07-01

    Breast cancer is one of the most serious problems in oncology. We investigated the antitumor potential of lycopene (Lyco) alone or combined with tocopherol (Lyco + Toco) for 90 days against a single oral dose of (50 mg/kg body weight) 7,12-dimethyl[a]benzanthracene (DMBA)-induced oxidative stress and mammary carcinogenesis in female rats. The treatment protocol started from the day immediately after DMBA administration. Results obtained indicated that there was a significant elevation in the levels of malondialdehyde (MDA) and nitric oxide (NO) in serum and breast tissues of DMBA-injected rats. The combined treatment (Lyco + Toco) group showed a potential reduction of these parameters more than Lyco alone group. The activities of superoxide dismutase, catalase, and glutathione peroxidase were found to be significantly higher when compared to rats treated with Lyco alone. In DMBA group, a positive significant correlation between NO and MDA (r = 0.92) was observed. Histopathological examination revealed the formation of tumor and angiogenesis in DMBA-induced rats and these abnormal changes were ameliorated by combined treatment with Lyco + Toco. In conclusion, these results suggested that supplementation of diet with Lyco and Toco provided antioxidant defense, with strong chemopreventive activity against DMBA-induced mammary tumors.

  3. Nuclear factor kappa B: a pro-inflammatory, transcription factor-mediated signalling pathway in lung carcinogenesis and its inhibition by nonsteroidal anti-inflammatory drugs.

    Science.gov (United States)

    Setia, Shruti; Sanyal, Sankar Nath

    2012-01-01

    9,10-Dimethyl benz(a)anthracene (DMBA), when injected intratracheally once at a dose of 20 mg/kg body weight, is found to induce lung cancer in rats. Two nonsteroidal anti-inflammatory drugs (NSAIDs), indomethacin and etoricoxib, are given orally daily as chemopreventive agents at a dose of 0.6 mg/kg body weight and 2 mg/kg body weight, respectively, along with DMBA. Morphologic and histologic analysis revealed the occurence of tumors and intense cellular proliferation in the DMBA-treated animals, whereas no such features were observed in the other groups. Nuclear factor κB, a nuclear transcription factor, and proliferating cell nuclear antigen, a cell proliferation antigen, were studied by immunoblotting and immunohistochemistry and their levels were markedly elevated in the DMBA group compared with the others. Oxidative stress parameters, as studied by the inducible nitric oxide synthase activity, and the levels of reactive oxygen and nitrogen species were found to be suppressed in the DMBA group. Furthermore, fluorescent staining of the isolated lung cells from bronchoalveolar lavage was performed to study apoptosis and alterations in the mitochondrial membrane potential, and the DMBA-induced lung cancer was found to be associated with high inner mitochondrial membrane potential and a suppressed level of apoptosis.

  4. Dose response study of conjugated fatty acid derived from safflower oil on mammary and colon carcinogenesis pretreated with 7,12-dimethylbenz[a]anthracene (DMBA) and 1,2-dimethylhydrazine (DMH) in female Sprague-Dawley rats.

    Science.gov (United States)

    Cheng, Jing Lei; Futakuchi, Mitsuru; Ogawa, Kumiko; Iwata, Toshio; Kasai, Masaaki; Tokudome, Shinkan; Hirose, Masao; Shirai, Tomoyuki

    2003-07-10

    To clarify the chemopreventive effects of conjugated fatty acid derived from safflower oil (CFA-S), rich in conjugated linoleic acid (CLA), on mammary and colon carcinogenesis, 6 week old female Sprague-Dawley (SD) rats received diet containing 0.01, 0.05, 0.1, 1, or 2% CFA-S subsequent to five times subcutaneous injections of 1,2-dimethyl-hydrazine (DMH) at a dose of 40 mg/kg b.w. and a single 50 mg/kg b.w. intragastric application of 7,12-dimethylbenz[a]anthracene (DMBA) during the first 11 days. The experiment was terminated at week 36. Numbers of mammary tumors, colon aberrant crypt foci (ACF), and proliferative indices of mammary tumors, and colon epithelium were analyzed. The 1% dose was found to be optimal for suppression of carcinogenesis in both target organs, a good correlation being noted with between data for cell proliferation. These results suggest that a diet containing appropriate levels of CFA-S may be useful for prevention of mammary and colon cancer.

  5. 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.

  6. Chemopreventive Activity of Honokiol against 7, 12 - Dimethylbenz[a]anthracene-Induced Mammary Cancer in Female Sprague Dawley Rats

    Directory of Open Access Journals (Sweden)

    Zhenyu Wang

    2017-05-01

    Full Text Available Breast cancer is a predominant cause of death in women across the globe. Chemoprevention by using natural, dietary or synthetic products has been appearing to be a fascinating approach to combat the growing burden of breast cancer. In the current study, we intended to explore the mechanisms of chemopreventive action of honokiol against 7, 12 - dimethylbenz[a]anthracene (DMBA-induced mammary cancer in female Sprague Dawlely (SD rats. We induced mammary cancer in SD rats by administering single dose of DMBA (80 mg/kg through intra gastric route. Chemopreventive effects of honokiol (80 mg/kg, i.p. were confirmed from its ameliorating effect on the DMBA-induced anomalies such as liver marker enzymes, Phases I and II metabolizing enzymes and oxidative stress markers. Further, honokiol reversed the DMBA-induced abnormalities in inflammatory cytokines levels and serum tumor markers. Additionally, histopathological examination of mammary tissue and protein expression analysis of NF-κB revealed that honokiol is effective against DMBA-induced mammary cancer. In summary, the results of our study support the chemopreventive feature of honokiol in mammary cancer.

  7. The micronucleus assay in mammalian cells in vitro to assess health benefits of various phytochemicals.

    Science.gov (United States)

    Meschini, Roberta; Berni, Andrea; Filippi, Silvia; Pepe, Gaetano; Grossi, Maria Rosaria; Natarajan, Adayapalam T; Palitti, Fabrizio

    2015-11-01

    We evaluated the protective effects of Gentiana lutea extracts (GLEx) and 6-Gingerol (6-G) on clastogenicity of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and 7,12-dimethylbenz(α) anthracene (DMBA) in vitro on HepG2 cells using the frequencies of induced micronuclei (MN) as the end point. Pre-, post- and simultaneous treatments with GLEx or 6-G and the carcinogens were carried out. Both GLEx post- and simultaneous treatments reduced the frequencies of MN induced by MNNG and DMBA. Probably this effect is due to an increase of cytostasis and a physico-chemical interaction between GLEx and DMBA under simultaneous treatment. Pre- and simultaneous treatments with 6-G significantly reduced the yield of MNNG-induced micronuclei without affecting % of cytostasis. Simultaneous treatment with 6-G plus DMBA resulted in reduction in the frequency of MN and an increase in cytotoxicity compared to sample treated alone with DMBA, whereas a post-treatment, caused a significant decrease in the yield of MN compared with DMBA alone without any cytotoxic effect. These results are compared with our earlier data obtained in the same system with other phytochemicals. It is concluded that for a critical evaluation of the protective effects of phytochemicals, both the influence on the induced MN and induced cytostasis have to be considered. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. 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.

  9. Endogenous estrogen status, but not genistein supplementation, modulates 7,12-dimethylbenz[a]anthracene-induced mutation in the liver cII gene of transgenic big blue rats.

    Science.gov (United States)

    Chen, Tao; Hutts, Robert C; Mei, Nan; Liu, Xiaoli; Bishop, Michelle E; Shelton, Sharon; Manjanatha, Mugimane G; Aidoo, Anane

    2005-06-01

    A growing number of studies suggest that isoflavones found in soybeans have estrogenic activity and may safely alleviate the symptoms of menopause. One of these isoflavones, genistein, is commonly used by postmenopausal women as an alternative to hormone replacement therapy. Although sex hormones have been implicated as an important risk factor for the development of hepatocellular carcinoma, there are limited data on the potential effects of the estrogens, including phytoestrogens, on chemical mutagenesis in liver. Because of the association between mutation induction and the carcinogenesis process, we investigated whether endogenous estrogen and supplemental genistein affect 7,12-dimethylbenz[a]anthracene (DMBA)-induced mutagenesis in rat liver. Intact and ovariectomized female Big Blue rats were treated with 80 mg DMBA/kg body weight. Some of the rats also received a supplement of 1,000 ppm genistein. Sixteen weeks after the carcinogen treatment, the rats were sacrificed, their livers were removed, and mutant frequencies (MFs) and types of mutations were determined in the liver cII gene. DMBA significantly increased the MFs in liver for both the intact and ovariectomized rats. While there was no significant difference in MF between the ovariectomized and intact control animals, the mutation induction by DMBA in the ovariectomized groups was significantly higher than that in the intact groups. Dietary genistein did not alter these responses. Molecular analysis of the mutants showed that DMBA induced chemical-specific types of mutations in the liver cII gene. These results suggest that endogenous ovarian hormones have an inhibitory effect on liver mutagenesis by DMBA, whereas dietary genistein does not modulate spontaneous or DMBA-induced mutagenesis in either intact or ovariectomized rats.

  10. Modulation of miR-203 and its regulators as a function of time during the development of 7, 12 dimethylbenz [a] anthracene induced mouse skin tumors in presence or absence of the antitumor agents

    International Nuclear Information System (INIS)

    Tiwari, Prakash; Gupta, Krishna P.

    2014-01-01

    We investigated the chemopreventive effects of naturally occurring compounds like butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG) individually or in combination in 7, 12-dimethylbenz [a] anthracene (DMBA) treated mouse skin at 4 and 16 weeks, the time before and after the tumor development. DMBA application did not show any skin tumors at 4 weeks but well defined tumors appeared at 16 weeks. BA, NA or CAG prevented the tumor development significantly but the protection was highly enhanced when all these compounds were given together. In order to see the molecular changes progressing with tumors, we showed the downregulation of tumor suppressor miR-203 at 16 weeks and upregulation of histone deacetylases (HDAC), DNA methyltransferase, promoter methylation of miR-203 at 4 or 16 weeks. Regulators of micro RNA biogenesis such as DICER1 and Ago2 were also deregulated by DMBA. Proto-oncogene c-myc and BMI1 were upregulated and tumor suppressor gene p16 was downregulated by DMBA as a function of time. Effects of BA, NA or CAG were more pronounced after 16 weeks as compared to 4 weeks in preventing the tumor development and altered gene expression. Concomitant administration of BA, NA and CAG tried to prevent these alterations more effectively than that of individual compound possibly by regulating miR-203 status through epigenetic or biogenetic modulations before and after the tumor development. Study provides a rationale for chemoprevention by combination of different compounds targeting miR-203. - Highlights: • DMBA modulates miR-203 and its regulator before and after the onset of tumors. • Suppression of miR-203 and p16 could be the result of gene promoter methylation. • BA, NA or CAG prevents the effects of DMBA. • Combination of BA, NA or CAG is more effective in preventing the DMBA modulations

  11. Role of chemical carcinogens in epithelial and mesenchymal neoplasms with tumor initiation-promotion protocol and the effect of 13-cis retinoic acid in chemo prevention

    International Nuclear Information System (INIS)

    Bukhari, S.M.H.; Shahzad, S.Q.; Naeem, S.; Qureshi, G.R.; Naveed, I.A.

    2002-01-01

    Objective: To study the effects of chemical carcinogens on epithelial and mesenchymal tumorigenesis with tumor initiation-promotion protocol and the use of 13-cis retinoic acid as a chemo preventive agent. Design: It was an experimental study. Place and Duration of Study: The study was conducted at Postgraduate Medical Institute (PGML) Lahore for 20 weeks. Materials and Methods: Sixty albino rats were divided into six groups of ten of animals each. First group of animals (control) was not given carcinogens and 13-cis retinoic acid in second group DMBA was applied on the dorsal skin in repeated dos of 100 mu g/ml in acetone, twice a weak. In the third group DMBA was given 100 mu g/ml as single dose while TPA was given 10 mu g//ml in acetone, twice a weak after two weeks of DMBA applications. In fourth group only DMBA 100 mu g/ml in acetone was applied as a single dose. In fifth and sixth groups 13-cis retinoic acid was given topically before and after the application of DMBA and TPA. Results: First and fourth groups did not develop any tumor. In second groups 2 animals developed malignant fibrous histiocytoma, 4 squamous cell carcinoma while 1 dysphasia and 1 carcinoma in situ. Third group developed osteoma (3 animals), papilloma (3 animals, squamous cell carcinoma (01) and dysplasia (01). Conclusion: Our results showed that DMBA acts as tumor initiator while TPA as promoter. DMBA also produces tumors itself when given alone in repeated doses. The chemical carcinogens are not only a cause of epithelial carcinogenesis but also responsible for mesenchymal tumorigenesis. 13 cis retinoic acid was equally effective in both stages of tumorigenesis. It also prevents malignant conversion of chemically induced benign tumors. (author)

  12. Ulva lactuca polysaccharides prevent Wistar rat breast carcinogenesis through the augmentation of apoptosis, enhancement of antioxidant defense system, and suppression of inflammation

    Directory of Open Access Journals (Sweden)

    Abd-Ellatef GF

    2017-02-01

    Full Text Available Gamal-Eldein F Abd-Ellatef,1 Osama M Ahmed,2 Eman S Abdel-Reheim,2 Abdel-Hamid Z Abdel-Hamid,1 1Pharmaceutical and Drug Industries Research Division, Therapeutic Chemistry Department, National Research Centre, Cairo, Egypt; 2Division of Physiology, Department of Zoology, Faculty of Science, Beni-Suef University, Beni-Suef, Egypt Background: Recently, several research studies have been focused on the isolation and function of the polysaccharides derived from different algal species, which revealed multiple biological activities such as antioxidant and antitumor activities. This study assesses the possible breast cancer chemopreventive properties of common seaweeds, sea lettuce, Ulva lactuca (ulvan polysaccharides using in vitro bioassays on human breast cancer cell line (MCF-7 and an in vivo animal model of breast carcinogenesis. Methods: Cytotoxic effect of ulvan polysaccharides on MCF-7 was tested in vitro. For an in vivo investigation, a single dose of 25 mg/kg body weight 7,12-dimethylbenz[a]anthracene (DMBA and ulvan polysaccharides (50 mg/kg body weight every other day for 10 weeks were administered orally to the Wistar rats. Results: Deleterious histopathological alterations in breast tissues including papillary cyst adenoma and hyperplasia of ductal epithelial lining with intraluminal necrotic materials and calcifications were observed in the DMBA-administered group. These lesions were prevented in the DMBA-administered group treated with ulvan polysaccharides. The immunohistochemical sections depicted that the treatment of DMBA-administered rats with ulvan polysaccharides markedly increased the lowered pro-apoptotic protein, p53, and decreased the elevated anti-apoptotic marker, bcl2, expression in the breast tissue. The elevated lipid peroxidation and the suppressed antioxidant enzyme activities in DMBA-administered control were significantly prevented by the treatment with ulvan polysaccharides. The elevated levels of inflammatory

  13. Reação de bis-inserção de 1,2-difenilacetileno na ligação Pd-C de ciclometalados Bis insertion reaction of 1,2-diphenylacetilene into Pd-C bond of cyclometallated species

    Directory of Open Access Journals (Sweden)

    Sandra Regina Ananias

    2003-01-01

    Full Text Available The present paper deals with the bis-insertion reactions of 1,2-diphenylacetylene into Pd-C bond of the cyclopalladated complexes [Pd(dmba(µ-NCO]2 (1 and [Pd(dmba(MeCN2](NO3 (2 (dmba = N,N-dimethylbenzylamine, MeCN = acetonitrile. Two new complexes [Pd{PhC=CPh-CPh=CPhC6H4CH2N(CH 32}(NCO] (3 and [Pd{PhC=CPh-CPh=CPhC6H4CH2N(CH 32}(NO3 ] (4 were obtained and characterized by IR and NMR spectroscopy and elemental analysis.

  14. Downregulation of NF-κB and PCNA in the regulatory pathways of apoptosis by cyclooxygenase-2 inhibitors in experimental lung cancer.

    Science.gov (United States)

    Setia, Shruti; Sanyal, Sankar Nath

    2012-10-01

    Non-steroidal anti-inflammatory drugs (NSAIDs) are emerging as novel chemopreventive agents against a variety of cancers owing to their capability in blocking the tumor development by cellular proliferation, angiogenesis and by promoting apoptosis. The present study further explored the comparative role of a traditional NSAID, indomethacin and a newly developed coxib, etoricoxib against 9,10-dimethylbenz(a)anthracene (DMBA)-induced lung carcinogenesis in rats. Morphological and histological analysis revealed the occurrence of tumors and lesions along with constricted alveolar spaces in the DMBA treated animals which were largely corrected both by indomethacin and etoricoxib. COX-1 was found to be uniformly expressed in all the groups while COX-2 levels were raised prominently in the DMBA treated animals. Proliferation, as studied by PCNA expression was found to be markedly increased in the DMBA group as compared to the others. Increased NF-κB expression in the DMBA group was found to correct with the co-administration of NSAIDs. Also, fluorescent co-staining of the isolated lung cells revealed a significantly decreased apoptosis and altered mitochondrial membrane potential. In conclusion, these parameters indicate to the chemopreventive action of the two NSAIDs studied in lung cancer and as their mechanism of action suggests, can be achievable both by COX-dependent and COX-independent pathways.

  15. Metformin inhibits 7,12-dimethylbenz[a]anthracene-induced breast carcinogenesis and adduct formation in human breast cells by inhibiting the cytochrome P4501A1/aryl hydrocarbon receptor signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Maayah, Zaid H. [Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451 (Saudi Arabia); Ghebeh, Hazem [Stem Cell & Tissue Re-Engineering, King Faisal Specialist Hospital and Research Center, Riyadh 11211 (Saudi Arabia); Alhaider, Abdulqader A. [Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451 (Saudi Arabia); Camel Biomedical Research Unit, College of Pharmacy and Medicine, King Saud University, Riyadh 11451 (Saudi Arabia); El-Kadi, Ayman O.S. [Faculty of Pharmacy & Pharmaceutical Sciences, University of Alberta, Edmonton (Canada); Soshilov, Anatoly A.; Denison, Michael S. [Department of Environmental Toxicology, University of California at Davis, Davis, CA 95616 (United States); Ansari, Mushtaq Ahmad [Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451 (Saudi Arabia); Korashy, Hesham M., E-mail: hkorashy@ksu.edu.sa [Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451 (Saudi Arabia)

    2015-04-15

    Recent studies have established that metformin (MET), an oral anti-diabetic drug, possesses antioxidant activity and is effective against different types of cancer in several carcinogen-induced animal models and cell lines. However, whether MET can protect against breast cancer has not been reported before. Therefore, the overall objectives of the present study are to elucidate the potential chemopreventive effect of MET in non-cancerous human breast MCF10A cells and explore the underlying mechanism involved, specifically the role of cytochrome P4501A1 (CYP1A1)/aryl hydrocarbon receptor (AhR) pathway. Transformation of the MCF10A cells into initiated breast cancer cells with DNA adduct formation was conducted using 7,12-dimethylbenz[a]anthracene (DMBA), an AhR ligand. The chemopreventive effect of MET against DMBA-induced breast carcinogenesis was evidenced by the capability of MET to restore the induction of the mRNA levels of basic excision repair genes, 8-oxoguanine DNA glycosylase (OGG1) and apurinic/apyrimidinic endonuclease1 (APE1), and the level of 8-hydroxy-2-deoxyguanosine (8-OHdG). Interestingly, the inhibition of DMBA-induced DNA adduct formation was associated with proportional decrease in CYP1A1 and in NAD(P)H:quinone oxidoreductase 1 (NQO1) gene expression. Mechanistically, the involvements of AhR and nuclear factor erythroid 2-related factor-2 (Nrf2) in the MET-mediated inhibition of DMBA-induced CYP1A1 and NQO1 gene expression were evidenced by the ability of MET to inhibit DMBA-induced xenobiotic responsive element and antioxidant responsive element luciferase reporter gene expression which suggests an AhR- and Nrf2-dependent transcriptional control. However, the inability of MET to bind to AhR suggests that MET is not an AhR ligand. In conclusion, the present work shows a strong evidence that MET inhibits the DMBA-mediated carcinogenicity and adduct formation by inhibiting the expression of CYP1A1 through an AhR ligand-independent mechanism

  16. Metformin inhibits 7,12-dimethylbenz[a]anthracene-induced breast carcinogenesis and adduct formation in human breast cells by inhibiting the cytochrome P4501A1/aryl hydrocarbon receptor signaling pathway

    International Nuclear Information System (INIS)

    Maayah, Zaid H.; Ghebeh, Hazem; Alhaider, Abdulqader A.; El-Kadi, Ayman O.S.; Soshilov, Anatoly A.; Denison, Michael S.; Ansari, Mushtaq Ahmad; Korashy, Hesham M.

    2015-01-01

    Recent studies have established that metformin (MET), an oral anti-diabetic drug, possesses antioxidant activity and is effective against different types of cancer in several carcinogen-induced animal models and cell lines. However, whether MET can protect against breast cancer has not been reported before. Therefore, the overall objectives of the present study are to elucidate the potential chemopreventive effect of MET in non-cancerous human breast MCF10A cells and explore the underlying mechanism involved, specifically the role of cytochrome P4501A1 (CYP1A1)/aryl hydrocarbon receptor (AhR) pathway. Transformation of the MCF10A cells into initiated breast cancer cells with DNA adduct formation was conducted using 7,12-dimethylbenz[a]anthracene (DMBA), an AhR ligand. The chemopreventive effect of MET against DMBA-induced breast carcinogenesis was evidenced by the capability of MET to restore the induction of the mRNA levels of basic excision repair genes, 8-oxoguanine DNA glycosylase (OGG1) and apurinic/apyrimidinic endonuclease1 (APE1), and the level of 8-hydroxy-2-deoxyguanosine (8-OHdG). Interestingly, the inhibition of DMBA-induced DNA adduct formation was associated with proportional decrease in CYP1A1 and in NAD(P)H:quinone oxidoreductase 1 (NQO1) gene expression. Mechanistically, the involvements of AhR and nuclear factor erythroid 2-related factor-2 (Nrf2) in the MET-mediated inhibition of DMBA-induced CYP1A1 and NQO1 gene expression were evidenced by the ability of MET to inhibit DMBA-induced xenobiotic responsive element and antioxidant responsive element luciferase reporter gene expression which suggests an AhR- and Nrf2-dependent transcriptional control. However, the inability of MET to bind to AhR suggests that MET is not an AhR ligand. In conclusion, the present work shows a strong evidence that MET inhibits the DMBA-mediated carcinogenicity and adduct formation by inhibiting the expression of CYP1A1 through an AhR ligand-independent mechanism

  17. Clerodendron inerme Protects Cellular Integrity During 7,12 ...

    African Journals Online (AJOL)

    Erythrocytes from DMBA painted hamsters were more fragile than those from control hamsters. The activity of membrane bound enzyme (Na+ K+ ATPase) decreased in DMBA painted hamsters as compared to control hamsters. Oral administration of aqueous leaf extract of Clerodendron inerme (CiALet) at a dose of

  18. Fate of 7,12-dimethylbenz(a)anthracene in rainbow trout, Salmo gairdneri

    International Nuclear Information System (INIS)

    Schnitz, A.R.; Squibb, K.S.; O'Connor, J.M.

    1987-01-01

    Polycyclic aromatic hydrocarbons (PAH) are contaminants of surface waters and sediments, especially near urban centers. Although aquatic biota accumulate PAHs from environmental sources, metabolism may be rapid, and biota sampled from contaminated areas often have concentrations lower than might be estimated from bioconcentration factors. In some cases PAH metabolism by aquatic biota may create reactive intermediates, some of which have been related to chronic effects in fishes. This report describes the fate and distribution of 7,12-dimethylbenz(a)anthracene (DMBA) after oral administration to rainbows trout (Salmo gairdneri). Emphasis has been placed on the disposition of DMBA among tissues and on DMBA transformation in the hepatobiliary system

  19. Lymphoma of SJL/J mice strain, 3

    International Nuclear Information System (INIS)

    Takahashi, Masanori; Takeichi, Sanae; Otsuka, Hisashi

    1976-01-01

    This paper describes influences of 7, 12-dimethylbenz (α) anthracene (DMBA) and 60 Co irradiation in lymphoma, together with the past results. The influences of DMBA in the lymphoma were studied 265 days (an average) after the subcutaneous administration of 1 mg/day of DMBA in 35 mice, and 246 days after it accompanied with the extraction of the thymus. Eight hundred rads (200 rads/ week four times) intermittent systemic irradiation was given to 26 mice, and to 16 mice after the extraction of the thymus. The influences on the lymphoma were studied 233 days later (an average) in the former and 544 days later (an average) in the latter. Lymphoma occurred 242 days later (an average) in 20 of the 35 mice with the administration of DMBA (57.1%), and 260 days later (an average) in 13 of the 42 mice with the administration of DMBA accompanied with the extraction of the thymus (30.9%). It occurred 231 days later (an average) in 22 of the 26 mice with 60 Co irradiation (84.6%), and 561 days later (an average) in 12 of the 16 mice with 60 Co irradiation accompanied with the extraction of the thymus (75%). Lymphosarcoma occurred 211 days after the administration of DMBA in 37%, and 208 days after the irradiation of 60 Co in 53.8%. However, it did not occur in animals in which the thymus had been extracted. The frequency of thymic lymphoma was high in animals with the administration of N-nitrosobutylurea. Although the occurrence of lymphosarcoma was controlled after the extraction of the thymus, reticulosarcoma occurred. The time of occurrence of lymphoma and the frequency of its occurrence by tissues were the same in the mice with extraction of the thymus as in controls. The SJL/J strain mice seemed to be independent of the thymus. (Kanao, N.)

  20. Breast cancer prevention with Morinda citrifolia (noni at the initiation stage

    Directory of Open Access Journals (Sweden)

    Mian-Ying Wang

    2013-06-01

    Full Text Available ABSTRACTBackground: It has been reported that noni has multiple health benefits for over 2000 years. In this study, the cancer preventive effects of Tahitian noni® juice (TNJ at the initiation stage on DMBA-induced mammary tumorigenesis in female SD rats was investigated.Objective: We took advantage of the DMBA-induced mammary carcinogenic model to study the preventive effects of TNJ at the initiation stage of mammary carcinogenesis in female SD rats by using clinical observation, pathological examination, and 32P-postlabeling assay.Methods: One hundred and sixty female SD rats were divided into eight groups with 20 rats in each group. Three doses of TNJ or placebo was given to the animals at the age of 35 days until the end of the experiment. When the animals were 55 days old, 25 mg/kg DMBA was fed to the animals in the DMBA group, placebo, and TNJ groups. The 20 rats were kept at age-matched controls. Palpable tumors were examined twice a week after DMBA administration in each group by an experienced professional. The size of tumor was measured by a graduated caliper. A piece of tumor, vascularization area, and mammary glands in the thoracic and abdomen areas of each rat were dissected respectively and fixed in 10% neutral buffered formalin for light microscope examination. The DMBA-DNA adduct formation in mammary tissues was detected by 32P-postlabeling assay.Results: The tumor latency in TNJ groups was delayed about 60-90 days when compared with positive controls. The number of palpable tumors per group was significantly reduced by 73%, 72% and 80% in 3%, 5%, and 10% TNJ groups respectively when compared with positive controls at the end of 330 days after DMBA administration. The number of palpable tumors in the placebo groups was slightly reduced in the early stage, but much less than that in the TNJ groups. The multiplicity and malignancy of lesions were significantly reduced and the survival rate of animals in the TNJ groups was

  1. Potential of Anti Breast Cancer Black Ethanol Rice Extract (Oryza sativa L. indica In Decreasing Levels of CA 15-3 Serum in the White Mice Sprague dawley in Induction 7.12-Dimethylbenz (α Antracene (DMBA and Estrogen

    Directory of Open Access Journals (Sweden)

    Zanuar Abidin

    2017-01-01

    Full Text Available Breast cancer is cancer that has the high incidence in Indonesia. Black rice (Oryza sativa L. indica is a plant that has an anticancer potency. This research aim is to prove black rice as a potential anticancer by using experimental animals, 20 Sprague Dawley female rats aged 7-8 weeks induced breast cancer by using the combination of 7,12-dimethylbenz (α anthracene (DMBA and estrogen. Rats were divided into two groups, namely the K-induced breast cancer and a group of P-induced cancer and treated with black rice. Black rice is given in the form of ethanol extract at a dose of 75 mg / kg / day for six weeks. Levels of CA 15-3 serum are used as a parameter. The result showed that the differences in levels of serum CA 15-3 are significant (p <0.05. Serum CA 15-3 level in P group is lower than in K group. This study proved that the ethanol extract of black rice (Oryza sativa L. indica has potential as an anticancer breast as indicated by decreased level of serum CA 15-3

  2. Studies on the tumor initiation/promotion potential of six middle distillates (MDs) in mouse skin.

    Science.gov (United States)

    Jungen, H; Mellert, W; Wenzel-Hartung, R

    1995-08-01

    Six middle distillates (MDs) were tested for tumor initiating/promoting activity after application to the skin of 30 male CD-1 (ICR) BR mice per group. As the control, 7,12-dimethylbenz[a]-anthracene (DMBA) was used for initiation followed by 12-O-tetradecanoylphorbol-13-acetate (TPA) for promotion. For assessing the tumor-initiating activity, 50 microliters of neat MDs was administered for 5 days with subsequent TPA promotion. In the promotion bioassay, after DMBA initiation 50 microliters of the neat MDs was administered twice weekly until Week 28. For the examination of complete carcinogenic activity, one MD was given without DMBA initiation. Hyperkeratosis, hyperplasia, and dermal inflammation, occurring during the initiation with the MDs, were completely reversible during the 2-week treatment-free period after initiation. Similar skin findings were observed during promotion with the MDs. Regarding the number of affected animals and the severity of the response, TPA was more irritating than the MDs. The initiation study revealed skin tumors for the DMBA/TPA control (30/30), MD 57,389 (14/30), MD 57,396 (5/30), MD 57,383 (4/30) and MD 57,324 (2/30). The promotion study revealed tumor induction by MDs 57,389 (9/30), 57,324 (1/30), 57,393 (1/30), and 57,396 (1/30). Two of 30 animals treated with MD 57,389 developed tumors without DMBA initiation thus indicating that it also is a complete carcinogen. MD 57,399 caused neither initiating nor promoting effects. The tumors observed were diagnosed histopathologically predominantly as squamous cell papillomas.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. The effect of diet, exercise, and 7,12-dimethylbenz(a)anthracene on food intake, body composition, and carcass energy levels in virgin female BALB/c mice

    Science.gov (United States)

    Lane, Helen W.; Keith, Robert E.; Strahan, Susan; White, Marguerite T.

    1991-01-01

    The effects of diet, exercise, and 7,12-dimethylbenz(a)anthracene (DMBA), a mammary-tumor carcinogen, on food intake, energy consumption, body weight, and body composition in virgin female BALB/c mice are investigated. Diet, exercise, and DMBA all had pronounced effects on energy consumption, which in turn affected body composition. These treatments may influence manifestations of breast cancer via their effects on body composition.

  4. Polycyclic aromatic hydrocarbon-induced CYP1B1 activity is suppressed by perillyl alcohol in MCF-7 cells

    International Nuclear Information System (INIS)

    Chan, Nelson L.S.; Wang Huan; Wang Yun; Leung, H.Y.; Leung, Lai K.

    2006-01-01

    Perillyl alcohol (POH) is a dietary monoterpene with potential applications in chemoprevention and chemotherapy. Although clinical trials are under way, POH's physiological and pharmacological properties are still unclear. In the present study, the effect of POH on polycyclic aromatic hydrocarbon (PAH)-induced genotoxicity, and the related expression were examined in MCF-7 cells. Exposure to environmental toxicant increases the risk of cancer. Many of these compounds are pro-carcinogens and are biotransformed into their ultimate genotoxic structures by xenobiotic metabolizing enzymes. CYP1A1 and 1B1 are enzymes that catalyze the biotransformation of dimethylbenz[a]anthracene (DMBA). Our data revealed that 0.5 μM of POH was effective in blocking DMBA-DNA binding. Ethoxyresorufin-O-deethylase (EROD) assay indicated that the administration of POH inhibited the DMBA-induced enzyme activity in MCF-7 cells. Enzyme kinetic analysis revealed that POH inhibited CYP1B1 but not CYP1A1 activity. Quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) assay also demonstrated that the monoterpene reduced CYP1B1 mRNA abundance induced by DMBA. The present study illustrated that POH might inhibit and downregulate CYP1B1, which could protect against PAH-induced carcinogenesis

  5. Effects of aqueous cinnamon extract on chemically-induced carcinoma of hamster cheek pouch mucosa

    Directory of Open Access Journals (Sweden)

    Samah K. Ezzat

    2017-12-01

    Full Text Available This study aimed to investigate the effects of aqueous cinnamon extract (ACE on 7, 12-Dimethylbenz[a]anthracene (DMBA-induced oral carcinogenesis in hamster cheek pouch (HCP mucosa. Sixty male Syrian hamsters were randomly divided into six equal groups. The hamsters of groups I, II and III received no treatment, DMBA and ACE respectively, for 16 weeks. Groups IV and V were handled as group II and concomitantly treated with ACE for the same period and additionally group V received ACE for other 16 weeks after the stoppage of DMBA application. Group VI hamsters were handled as group III and additionally received DMBA for other 16 weeks after the stoppage of ACE supplementation. Hamsters of each group were euthanized according to the experimental schedule. The buccal pouches were and prepared for H&E stain, PAS reagent, CD3 and PDGF immunohistochemical reactivity. All groups showed dysplastic changes with varying degrees except groups I and III. Deep invasive carcinomas were recorded in 90% of the samples of group II, 60% of group IV, 50% of group V and 40% of group VI. From the previous results, it can be concluded that ACE has the potentiality preventing oral cancer initiation better than inhibiting oral cancer progression.

  6. Induction of lung cancer in rats by intratracheal insufflation of carcinogenic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Pylev, L N

    1963-01-01

    One, 3, or 5 monthly intratracheal injections of 2 to 2.5 mg dimethylbenzanthracene (DMBA) in India ink-solvent or 5 or 7 monthly injections of 5 mg benzyprene (BaP) in India ink-solvent into rats produced tumors, starting at 5 months, mostly around accumulations of ink. Results showed 27.8% of 151 animals receiving DMBA and surviving to 5 months developed carcinomas, as compared to 7 of 12 animals receiving BaP.

  7. Influence of caffeine and/or coffee consumption on the initiation and promotion phases of 7,12-dimethylbenz(a)anthracene-induced rat mammary gland tumorigenesis.

    Science.gov (United States)

    Welsch, C W; DeHoog, J V; O'Connor, D H

    1988-04-15

    The effect of caffeine and/or coffee consumption (via the drinking water) during the initiation phase and promotion phase of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary gland tumorigenesis in female Sprague-Dawley rats fed a commercial laboratory animal chow was examined. In the initiation studies, DMBA was administered once at 53-55 days of age; caffeine (100-860 mg/liter of drinking water) and/or coffee (moderate or high dose, sole source of drinking water) treatments were for 32 consecutive days, commencing 29 days prior to DMBA treatment and terminating 3 days after DMBA treatment. In the promotion studies, DMBA was administered once at 54-55 days of age; caffeine and/or coffee treatments were daily from 57-58 days of age to termination of experiments (12-21 weeks after carcinogen treatment). In the initiation studies, either moderate (100-400 mg) or high (860 mg) dose levels of caffeine or moderate to high dose levels of caffeinated coffee significantly (P less than 0.05) reduced mammary carcinoma multiplicity (number of tumors/rat). Consumption of high or moderate dose levels of decaffeinated coffee did not significantly alter mammary carcinoma multiplicity. The addition of caffeine to the moderate dose level of decaffeinated coffee resulted in a significant (P less than 0.05) reduction in mammary carcinoma multiplicity. In the promotion studies, prolonged consumption of moderated dose levels of caffeine or moderate or high dose levels of caffeinated coffee or decaffeinated coffee did not significantly effect mammary carcinoma multiplicity. In the early stages of promotion, however, a significant (p less than 0.05) stimulatory effect of caffeine on mammary carcinoma multiplicity was observed; an effect that was temperate and transitory. In both the initiation and promotion studies caffeine and/or coffee consumption did not significantly affect the incidence of mammary carcinomas (percentage of rats bearing mammary carcinomas) or the mean latency

  8. Co-oxidation of carcinogenic polycyclic aromatic hydrocarbons with some biologically active compounds (BAC)

    Energy Technology Data Exchange (ETDEWEB)

    Gubergrits, M.Y.

    1978-09-01

    Oxidation of benzo(a)pyrene (BP) initiated by UV or gamma irradiation was promoted by benz(a)anthracene and 7,12-dimethylbenz(a)anthracene (DMBA) and inhibited by pyrene, dibenz(a,c)anthracene, and asymmetric benz(a)antharacene. The effects of these BAC commonly occurring together with BP in industrial wastes, increased with their concentrations. Phenol and 3-methylcholanthrene strongly promoted BP oxidation when present at low concentrations and inhibited it at high concentrations. Consistent promoting effect was also observed in BP co-oxidation with adipic acid, ..cap alpha..-naphthoflavon, and vitamin E, whereas succinic, azelaic, ferulic, gallic, and chlorogenic acids, rutin, and vitamin C acted as inhibitors. Most saturated dicarboxylic acids studied did not affect BP oxidation at 1:1 acid-BP molar ratio. The kinetics of 7,12-DMBA photooxidation inhibition by some metabolic intermediates, e.g., DMBA endo-peroxide, were also studied.

  9. The influence of mouse vaccination with endogenous retrovirus on the development of tumor incluced by γ-irradiation or 7,12-Dimethylbenz(a)anthrocene

    International Nuclear Information System (INIS)

    Mazurenko, N.P.; Yakovleva, L.S.; Shcherbak, N.P.; Pavlovskaya, A.I.; Zueva, Yu.N.

    1987-01-01

    Mouse vaccination with alive endogenous N-tropic virus OA-3 inhibited and decreased the development of the Rauscher leukemia in C57B1/6 mice (B-type) and SWR mice (N-type) as well as development 7,12-dimethyl benzanthracene (DMBA) induced tumours in mouse hybrides (neither N-, nor B-types). The effect of vaccination was DMBA- or MLV-P-dose-dependent. Vaccination with the same virus did not affect the incidence of γ-irradiaton-induced leukemia in CBA mice (N-type) and C57B1/6 mice while it increased twice the incidence of radiation leukemia in DBA mice (N-type). However, the incidence of thymomas lowered in radiaton leukemia-bearing vaccinated mice of all the 3 strains, which may result from inhibition of murine thymotropic endogenous virus reproduction. The data obtained indicate the participation of murine own endogenous viruses in DMBA- or γ-irradiation induced carcinogenesis

  10. Raman spectroscopy detects biomolecular changes associated with nanoencapsulated hesperetin treatment in experimental oral carcinogenesis

    International Nuclear Information System (INIS)

    Gurushankar, K; Gohulkumar, M; Krishnakumar, N; Kumar, Piyush; Murali Krishna, C

    2016-01-01

    Recently it has been shown that Raman spectroscopy possesses great potential in the investigation of biomolecular changes of tumor tissues with therapeutic drug response in a non-invasive and label-free manner. The present study is designed to investigate the antitumor effect of hespertin-loaded nanoparticles (HETNPs) relative to the efficacy of native hesperetin (HET) in modifying the biomolecular changes during 7,12-dimethyl benz(a)anthracene (DMBA)-induced oral carcinogenesis using a Raman spectroscopic technique. Significant differences in the intensity and shape of the Raman spectra between the control and the experimental tissues at 1800–500 cm −1 were observed. Tumor tissues are characterized by an increase in the relative amount of proteins, nucleic acids, tryptophan and phenylalanine and a decrease in the percentage of lipids when compared to the control tissues. Further, oral administration of HET and its nanoparticulates restored the status of the lipids and significantly decreased the levels of protein and nucleic acid content. Treatment with HETNPs showed a more potent antitumor effect than treatment with native HET, which resulted in an overall reduction in the intensity of several biochemical Raman bands in DMBA-induced oral carcinogenesis being observed. Principal component and linear discriminant analysis (PC–LDA), together with leave-one-out cross validation (LOOCV) on Raman spectra yielded diagnostic sensitivities of 100%, 80%, 91.6% and 65% and specificities of 100%, 65%, 60% and 55% for classification of control versus DMBA, DMBA versus DMBA  +  HET, DMBA versus DMBA  +  HETNPs and DMBA  +  HET versus DMBA  +  HETNPs treated tissue groups, respectively. These results further demonstrate that Raman spectroscopy associated with multivariate statistical algorithms could be a valuable tool for developing a comprehensive understanding of the process of biomolecular changes, and could reveal the signatures of the

  11. Selective effects of whey protein concentrate on glutathione levels and apoptosis in rats with mammary tumors.

    Science.gov (United States)

    Cheng, Shih-Hsuan; Tseng, Yang-Ming; Wu, Szu-Hsien; Tsai, Shih-Meng; Tsai, Li-Yu

    2017-09-01

    Glutathione (GSH) plays an important role in antioxidant defense and regulation of apoptosis. GSH deficiency is related to many diseases, including cancer, and increased GSH levels in cancer cells are associated with chemotherapy resistance because of resistance to apoptosis. In this study, we investigated the effects of whey protein concentrate (WPC), a precursor of GSH, in rats with mammary tumors induced by treatment with 7,12-dimethylbenz(a)anthracene (DMBA). DMBA treatment results in cellular changes that mimic the initiation and promotion of carcinogenesis of breast tissue. We aimed to examine the possible preventive effects of diets containing whey protein on DMBA-induced mammary tumors in rats. The results indicate that WPC (0.334 g/kg) supplementation significantly increased the liver GSH levels by 92%, and were accompanied by low Bax/Bcl-2 ratio (from 5 to 3) and cleaved caspase-3/procaspase-3 ratio (from 2.4 to 1.2) in DMBA-treated rats. Furthermore, tumor GSH levels were decreased by 47% in WPC-supplemented rats, which resulted in increased Bax/Bcl-2 ratio (from 0.9 to 2) and cleaved caspase-3/procaspase-3 ratio (from 1.1 to 2.7). In conclusion, supplementation with WPC could selectively deplete tumor GSH levels and, therefore, WPC supplementation might be a promising strategy to overcome treatment resistance in cancer therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Topical application of dimethylbenz[a]anthracene results in the generation of multiple melanocytic nevi in C3H/HeN mice

    International Nuclear Information System (INIS)

    Elmets, Craig A.; Yusuf, Nabiha; Hamza, Sate; Iranikakh, Nasser; Smith, Jeffrey; Volk, Andrea L.; Skelton, Henry; Smith, Kathy

    2004-01-01

    Melanocytic nevi are a common dermatological problem for which there are few in vivo models. It has been postulated that environmental factors contribute to their development. Experiments were therefore conducted to determine whether application of dimethylbenz[a]anthracene (DMBA) to the skin of mice would result in the development of melanocytic nevi. One hundred microliters of a 0.1%, 0.5%, or 1.0% solution of DMBA was applied to the dorsal skin of C3H/HeN mice. The mice were then observed for the appearance of pigmented lesions. Histological examination revealed perifollicular accumulations of nevus cells, which were S-100-protein and HMB-45-positive, confirming their melanocytic origin. Pigmented lesions did not occur in animals treated with vehicle alone. Dose response studies revealed both greater numbers of nevi and lesions with larger diameters as the dose of DMBA was increased from 0.1% to 0.5%. In no instance was an invasive melanoma observed even after 40 weeks. The fact that melanocytic nevi can be produced by topical application of DMBA suggests that xenobiotics may play a previously unrecognized role in the development of this common benign neoplasm. Because this is one of the only animal models for melanocytic nevi, further examination of this model may facilitate identification of the molecular and biochemical mechanisms that lead to the development of pigmented nevi and the factors that promote their evolution into invasive melanomas

  13. Evaluation of carcinogenic potential of diuron in a rat mammary two-stage carcinogenesis model.

    Science.gov (United States)

    Grassi, Tony Fernando; Rodrigues, Maria Aparecida Marchesan; de Camargo, João Lauro Viana; Barbisan, Luís Fernando

    2011-04-01

    This study aimed to evaluate the carcinogenic potential of the herbicide Diuron in a two-stage rat medium-term mammary carcinogenesis model initiated by 7,12-dimethylbenz(a)anthracene (DMBA). Female seven-week-old Sprague-Dawley (SD) rats were allocated to six groups: groups G1 to G4 received intragastrically (i.g.) a single 50 mg/kg dose of DMBA; groups G5 and G6 received single administration of canola oil (vehicle of DMBA). Groups G1 and G5 received a basal diet, and groups G2, G3, G4, and G6 were fed the basal diet with the addition of Diuron at 250, 1250, 2500, and 2500 ppm, respectively. After twenty-five weeks, the animals were euthanized and mammary tumors were histologically confirmed and quantified. Tumor samples were also processed for immunohistochemical evaluation of the expressions of proliferating cell nuclear antigen (PCNA), cleaved caspase-3, estrogen receptor-α (ER-α), p63, bcl-2, and bak. Diuron treatment did not increase the incidence or multiplicity of mammary tumors (groups G2 to G4 versus Group G1). Also, exposure to Diuron did not alter tumor growth (cell proliferation and apoptosis indexes) or immunoreactivity to ER-α, p63 (myoephitelial marker), or bcl-2 and bak (apoptosis regulatory proteins). These findings indicate that Diuron does not have a promoting potential on mammary carcinogenesis in female SD rats initiated with DMBA.

  14. STUDY OF OVARIAN CHANGES IN RATS WITH MAMMARY CARCINOMAS

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    Maja Zečević

    2013-03-01

    Full Text Available The aim of this study was to estimate ovarian changes in 7,12 dimethylbenz (α anthracene (DMBA induced rat mammary carcinomas. The study was carried out on female virgin albino Wistar rats (n=35, age=35-37days, body mass 120-140g, divided into control (n=10 and experimental group (n=25. Anesthetised animals of experimental group were inoculated with 2 mg mixture (1 mg of DMBA and 1 mg of cholesterol-buffer into the fifth left mammary gland. The animals were sacrificed 90 days after implantation, and ovaries and mammary glands were investigated. Mammary gland carcinomas (in situ and/or invasive were pathohistologically verified in 19 experimental animals. Histological, histochemical, and immunohistochemical (cytokeratin AE1/AE3 and PCNA studies of ovaries were performed.Besides non-neoplastic changes, such as decrease in ovary’s volume, reduction in the rate of follicular development and numerous corpora lutea formation were found in the vicinity of preneoplastic changes: papillomatous epithelial hyperplasia and inclusion cysts, microglandular formations with dysplasia and seromucinous microcystic formation. Intensive diffuse PCNA expression was present in the epithelium of glandlike structures, follicular and inclusion cysts.These morphological changes confirmed that DMBA is a pluripotent carcinogen capable to induce a wide spectrum of preneoplastic lesions in the ovaries. The present dilemma is whether the changes described are the consequence of the direct effects of DMBA or of hormonal activity of the induced breast carcinomas, or both.

  15. Blueberry inhibits invasion and angiogenesis in 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral squamous cell carcinogenesis in hamsters via suppression of TGF-β and NF-κB signaling pathways.

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    Baba, Abdul Basit; Kowshik, Jaganathan; Krishnaraj, Jayaraman; Sophia, Josephraj; Dixit, Madhulika; Nagini, Siddavaram

    2016-09-01

    Aberrant activation of oncogenic signaling pathways plays a pivotal role in tumor initiation and progression. The purpose of the present study was to investigate the chemopreventive and therapeutic efficacy of blueberry in the hamster buccal pouch (HBP) carcinogenesis model based on its ability to target TGF-β, PI3K/Akt, MAPK and NF-κB signaling and its impact on invasion and angiogenesis. Squamous cell carcinomas were induced in the HBP by 7,12-dimethylbenz[a]anthracene (DMBA). The effect of blueberry on the oncogenic signaling pathways and downstream events was analyzed by quantitative real-time PCR and immunoblotting. Experiments with the ECV304 cell line were performed to explore the mechanism by which blueberry regulates angiogenesis. Blueberry supplementation inhibited the development and progression of HBP carcinomas by abrogating TGF-β and PI3K/Akt pathways. Although blueberry failed to influence MAPK, it suppressed NF-κB activation by preventing nuclear translocation of NF-κB p65. Blueberry also modulated the expression of the oncomiR miR-21 and the tumor suppressor let-7. Collectively, these changes induced a shift to an anti-invasive and anti-angiogenic phenotype as evidenced by downregulating matrix metalloproteinases and vascular endothelial growth factor. Blueberry also inhibited angiogenesis in ECV304 cells by suppressing migration and tube formation. The results of the present study suggest that targeting oncogenic signaling pathways that influence acquisition of cancer hallmarks is an effective strategy for chemointervention. Identification of modulatory effects on phosphorylation, intracellular localization of oncogenic transcription factors and microRNAs unraveled by the present study as key mechanisms of action of blueberry is critical from a therapeutic perspective. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Comparative evaluation of antiproliferative, antiangiogenic and apoptosis inducing potential of black tea polyphenols in the hamster buccal pouch carcinogenesis model

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    Prathiba Duvuru

    2007-01-01

    Full Text Available Abstract Background To evaluate the relative chemopreventive efficacy of two black tea polyphenols, Polyphenon-B [P-B] and BTF-35 on 7,12-dimethylbenz [a]anthracene (DMBA-induced hamster buccal pouch (HBP carcinogenesis. Methods Hamsters were divided into 6 groups. The right buccal pouches of animals in groups 1–3 were painted with 0.5% of DMBA three times a week for 14 weeks. While hamsters in group 1 received no further treatment, animals in groups 2 and 3 received diet containing 0.05% P-B and BTF-35 respectively, four weeks before DMBA painting that was continued until the end of the experiments. Animals in groups 4 and 5 were given P-B and BTF-35 alone respectively as in groups 2 and 3. Group 6 animals served as the untreated control. All the animals were sacrificed after 18 weeks. The expression of p21, cyclin D1, glutathione S-transferase pi (GST-P, nuclear factor kappa B (NF-κB, Bcl-2, Bax, cytochrome C, caspase-3, caspase-9, poly(ADP-ribose polymerase (PARP, cytokeratins and vascular endothelial growth factor (VEGF was analysed by RT-PCR, immunohistochemical and Western blot analyses. Results DMBA treated animals developed buccal pouch carcinomas that displayed increased expression of p21, cyclin D1, GST-P, NF-κB, cytokeratins, VEGF and Bcl-2 with decreased expression of Bax, cytochrome C, caspase-3, caspase-9, and PARP. Dietary administration of both P-B and BTF-35 reduced the incidence of DMBA-induced HBP carcinomas by modulating markers of cell proliferation, cell survival, tumour infiltration, angiogenesis, and apoptosis. Conclusion The results of the present study provide a mechanistic basis for the chemopreventive potential of black tea polyphenols. The greater efficacy of BTF-35 in inhibiting HBP carcinogenesis and modulating multiple molecular targets may have a potential role in the prevention of oral cancer.

  17. Peroxidase activity as a marker for estrogenicity

    International Nuclear Information System (INIS)

    Levy, J.; Liel, Y.; Glick, S.M.

    1981-01-01

    We examined the possibility that peroxidase activity might be a marker for estrogen activity in established estrogen-dependent tissues: dimethylbenz[a]anthracene (DMBA)-induced rat mammary tumours and human breast cancer. In DMBA-induced tumours undergoing regression after ovariectomy or tamoxifen treatment, tumour size decreased by 50%, estradiol receptors (ER) and progesterone receptors (PgR) decreased by 25 and 20%, respectively, but peroxidase activity paradoxically increased six- to sevenfold. In DMBA tumours stimulated by estradiol treatment or by the cessation of tamoxifen administration in intact rats, tumour size increased threefold. ER and PgR increased two- and threefold, respectively, while peroxidase activity decreased 50%. These data indicate an inverse relation between tumour growth, ER and PgR on the one hand, and peroxidase activity on the other. In the human breast cancers there was a singificant negative relation between the presence of ER and peroxidase activity. By using a calibrated Sephadex G-100 column it was shown that uterine peroxidase differs in molecular weight from the peroxidase of rat mammary tumours and that of human breast cancer. (author)

  18. The influence of melatonin on metabolic changes in female rats induced by continuous irradiation and/or administration of 7,12-dimethylbenz/a/anthracene

    International Nuclear Information System (INIS)

    Ahlers, I.; Solar, P.; Ahlersova, E.; Kassayova, M.; Smajda, B.

    1997-01-01

    Metabolic profile is an important biological marker of neoplastic processes not only in the tumor itself but also in the host organism. The neuro-hormone melatonin has been implicated in the experiments as an oncostatic agent. Female Wistar:Han SPF rats (Velaz, Prague, Czech Republic) were irradiated continuously for 15 days using a daily gamma rays dose of 96 mGy. At the end of exposure one group of rats was administered 5 mg/kg b.w. of dimethylbenz/a/anthracene (DMBA) intragastrically. During the period of exposure to ionizing radiation a part of the animals was supplied with melatonin (M) at a concentration of 20 μl/ml in drinking water. Selected parameters of lipid and carbohydrate metabolism and levels of selected hormones were determined 2, 30 and 100 days post-irradiation. The irradiation itself caused only small changes in tissue lipids. The application of a single low dose (subthreshold from the point of view of induction of mammary tumors) of DMBA caused more pronounced changes in nonirradiated animals; of the changes observed an increase in lipids in the liver, triacylglycerol (TG) in the thymus and decrease in myocardial glycogen predominated. The intake (by drinking) of exogenous M prevented the biochemical pattern of fatty liver in animals administered DMBA in both groups, irradiated an nonirradiated. A Prolonged effect of exogenous M, demonstrated by prevention of increase in TG in the thymus and of irradiated animals caused by administration of DMBA, was observed. The mechanism of metabolic effect of M is not known. Additional experiments are needed to explain the relationship between the beneficial effect of M on metabolic changes and its presumable oncostatic effect in rats. (author)

  19. Effect of dietary supplementation on the prognostic value of urinary and serum 8-isoprostaglandin F2α in chemically-induced mammary carcinogenesis in the rat

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    Białek Sławomir

    2011-03-01

    Full Text Available Abstract Backround The aim of the present study was to assess the effects of zinc or copper and polyphenolic compounds on the 8-isoprostaglandin F2α concentration in the serum and urine of rats with mammary cancer (adenocarcinoma induced with 7,12-dimethylbenz[a]antracene. The research focused on the kinetics of alterations in urinary 8-isoPGF2α at the early stage of carcinogenesis as well as the influence of dietary factors on the process. The impact of selected compounds on the intensity of DMBA - induced carcinogenesis was also assessed. Result and conclusions Administration of DMBA, a compound that inducers mammary tumors in experimental animals, increased the serum and urinary 8-isoPGF2α levels in study rats. In the rat model, diet supplementation with zinc, combined with selected polyphenolic compounds (resveratrol or genistein yielded a statistically significant decrease in the rat serum and urinary biomarker concentration with a simultaneously significant stimulation of carcinogenesis. The results indicate that there is an inverse correlation between the intensity of DMBA-induced carcinogenicity and the level of 8-isoPGF2α in urine and serum of rats.

  20. Induction of experimental mammary carcinogenesis in rats with 7,12-dimethylbenz(aanthracene Indução da carcinogênese mamária experimental em ratas com 7,12-dimetilbenz(aantraceno

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    Alfredo Carlos S. D. Barros

    2004-01-01

    Full Text Available PURPOSE: To test an experimental model of chemical mammary carcinogenesis induction in rats. METHODS: Twenty young virgin Sprague-Dawley female rats, aged 47 days, received 20 mg of 7,12-dimethylbenz(aanthracene (DMBA intragastrically by gavage. Afterwards, at 8 and 13 weeks, their mammary glands were examined. At the end of the experiment, the animals were sacrificed, and the mammary tumors were measured and weighed. Tumor fragments were analyzed using light microscopy. RESULTS: Eight weeks after DMBA injection, 16 rats presented at least 1 breast tumor (80%. After 13 weeks, all of them (100% developed breast carcinomas that were confirmed by histopathological analysis. CONCLUSION: This experimental animal model of chemical mammary induced carcinogenesis is feasible and can be used in further experiments on the role of tumorigenic biomodulator substances.OBJETIVO: Testar um modelo experimental de indução química de carcinogênese mamária em ratas. MATERIAL E MÉTODOS: Com 47 dias de vida, 20 ratas Sprague-Dawley, jovens e virgens, receberam por gavagem intragástrica 20 mg de 7,12-dimetilbenz(aantraceno (DMBA. Oito e 13 semanas depois da injeção de droga as mamas das ratas foram examinadas. Ao final os animais foram sacrificados e fragmentos dos tumores foram estudados ao microscópio. RESULTADO: Oito semanas depois da injeção de DMBA 16 ratas apresentavam tumor nas mamas (80%. Com 13 semanas todas desenvolveram carcinomas de mama (100%, que foram confirmados por análise histopatológica. CONCLUSÃO: Este modelo experimental de indução química de carcinogênese mamária é factível e pode ser empregado em futuras pesquisas para avaliar o papel de substâncias biomoduladoras da tumorigênese.

  1. Epidermal changes following application of 7,12-dimethylbenz(a)anthracene and 12-O-tetradecanoylphorbol-13-acetate to human skin transplanted to nude mice studied with histological species markers

    International Nuclear Information System (INIS)

    Graem, N.

    1986-01-01

    Effects of the tumor initiator 7,12-dimethylbenz(a)anthracene (DMBA) and of the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) on epidermis of human fetal and adult skin were studied in the nude mouse/human skin model. Human skin grafts on NC nude mice were exposed to two topical applications of 1 mg of DMBA in 50 microliter of acetone with an interval of 3 days and/or to applications of 10 micrograms of TPA in 50 microliter of acetone twice weekly. In some animals, it was attempted to augment the susceptibility of the grafts to the tumor-initiating effect of DMBA by pretreatment with TPA or ultraviolet light. The mice were sacrificed 8-32 wk after the initial treatment. Tumors did not appear in the central portions of any of the grafts, but epidermal tumors were seen at the graft border in 34.9% of the DMBA-treated animals. To identify human epidermis on the grafts and to determine the species origin of the induced tumors, two independently working histological marker methods were applied. (a) The first is detection of a human Blood Group B-like antigen present in mouse epidermis and in chemically induced murine epidermal tumors. This antigen cannot be demonstrated in human epidermis and in epidermal tumors of human patients. (b) The second is histological staining with the DNA-specific fluorochrome, bisbenzimide, displaying a characteristic pattern of 5-10 intranuclear fluorescent bodies in murine nonneoplastic epidermal cells and in murine epidermal tumor cells. Such a pattern is not seen in human epidermis and in epidermal tumors of human patients. The studies showed that TPA treatment resulted in epidermal hyperplasia in both the human epidermis and the adjacent mouse epidermis and that the induced tumors were derived from murine tissue

  2. Squamous cell hyperplastic foci: precursors of cutaneous papillomas induced in SENCAR mice by a two-stage carcinogenesis regimen.

    Science.gov (United States)

    Binder, R L; Johnson, G R; Gallagher, P M; Stockman, S L; Sundberg, J P; Conti, C J

    1998-10-01

    We have conducted a series of experiments to characterize the lesions that are precursors of cutaneous papillomas in SENCAR mice initiated with 7,12-dimethylbenz(a)anthracene (DMBA) and promoted with 12-O-tetradecanoylphorbol-13-acetate (TPA). The first grossly detectable lesions at sites where papillomas subsequently developed were papules, slightly raised areas of skin ranging in diameter from 0.25 to approximately 1.5 mm. Papules were first detected in DMBA-initiated mice 21 days after the start of dosing with TPA. Of 78 DMBA/TPA-induced papules tracked during 15 weeks of TPA treatments, 68% progressed to papillomas, 9% persisted as papules, and 22% completely regressed. Histological evaluation of serial sections of 69 DMBA/TPA-induced papules revealed that they were focal hyperplastic lesions that we refer to as squamous cell hyperplastic foci (SCHF). These hyperproliferative lesions appeared to progress through two distinct stages. Stage I SCHF were characterized as regular hyperplastic foci involving the interfollicular epidermis and the outer root sheaths of 1 or more hair follicles down to the level of the sebaceous glands. Stage II SCHF were foci of irregular epithelial hyperplasia with increased fibrovascular stroma and involved from 3 to >10 hair follicles. Prominent dilated capillaries and inflammatory cell infiltrates were frequently associated with both stage I and II SCHF. Ha-ras gene codon 61 mutations were detected in 7 of 10 stage I SCHF and 13 of 14 stage II SCHF microdissected from histological sections and 7 of 7 of whole papules by mutation-specific PCR analysis. These data provide molecular evidence that SCHF are foci of initiated cells. Further study of these lesions may contribute to more fully defining the sequence of molecular and cellular changes necessary for tumorigenesis in mouse skin. SCHF may also have utility as early indicators of potential skin tumorigenicity in cancer bioassays.

  3. Red Mold Rice Mitigates Oral Carcinogenesis in 7,12-Dimethyl-1,2-Benz[a]anthracene-Induced Oral Carcinogenesis in Hamster

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    Ruei-Lan Tsai

    2011-01-01

    Full Text Available The prevalence of oral tumor has exponentially increased in recent years; however, the effective therapies or prevention strategies are not sufficient. Red mold rice is a traditional Chinese food, and several reports have demonstrated that red mold rice had an anti-tumor effect. However, the possible anti-tumor mechanisms of the red mold rice are unclear. In this study, we examined the anti-tumor effect of red mold rice on 7,12-dimethyl-1,2-benz[a]anthracene (DMBA-induced oral tumor in hamster. The ethanol extract of red mold rice (RMRE treatment significantly decreases the levels of DMBA-induced reactive oxygen species, nitro oxide and prostaglandin E2 than those of the lovastatin-treated group (P < .001. Moreover, RMRE decreases the formation of oral tumor induced by DMBA. Monacolin K, monascin, ankaflavin or other red mold rice metabolites had been reported to decrease inflammation and oxidative stress and exerted anti-tumor effects. Therefore, we evaluated the anti-inflammation and anti-oxidative stress effects of monacolin K, monascin, ankaflavin and citrinin in lipopolysaccharide-treated RAW264.7 cells. We found that RMRE reduced the LPS-induced nitrite levels in RAW264.7 cells better than monacolin K, monascin, ankaflavin or citrinin (P < .05.

  4. JWA deficiency suppresses dimethylbenz[a]anthracene-phorbol ester induced skin papillomas via inactivation of MAPK pathway in mice.

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    Zhenghua Gong

    Full Text Available Our previous studies indicated that JWA plays an important role in DNA damage repair, cell migration, and regulation of MAPKs. In this study, we investigated the role of JWA in chemical carcinogenesis using conditional JWA knockout (JWA(Δ2/Δ2 mice and two-stage model of skin carcinogenesis. Our results indicated that JWA(Δ2/Δ2 mice were resistant to the development of skin papillomas initiated by 7, 12-dimethylbenz(aanthracene (DMBA followed by promotion with 12-O-tetradecanoylphorbol-13-acetate (TPA. In JWA(Δ2/Δ2 mice, the induction of papilloma was delayed, and the tumor number and size were reduced. In primary keratinocytes from JWA(Δ2/Δ2 mice, DMBA exposure induced more intensive DNA damage, while TPA-promoted cell proliferation was reduced. The further mechanistic studies showed that JWA deficiency blocked TPA-induced activation of MAPKs and its downstream transcription factor Elk1 both in vitro and in vivo. JWA(Δ2/Δ2 mice are resistance to tumorigenesis induced by DMBA/TPA probably through inhibition of transcription factor Elk1 via MAPKs. These results highlight the importance of JWA in skin homeostasis and in the process of skin tumor development.

  5. Fracture surface analysis on nano-SiO{sub 2}/epoxy composite

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Rongguo [Institute of Fundamental Mechanics and Material Engineering, Xiangtan University, Hunan 411105 (China); Key Laboratory of Low Dimensional Materials and Application Technology, Xiangtan University, Ministry of Education, Hunan 411105 (China)], E-mail: zhaorongguo@xtu.edu.cn; Luo Wenbo [Institute of Fundamental Mechanics and Material Engineering, Xiangtan University, Hunan 411105 (China); Key Laboratory of Low Dimensional Materials and Application Technology, Xiangtan University, Ministry of Education, Hunan 411105 (China)

    2008-06-15

    Fracture surface morphologies of nano-SiO{sub 2}/epoxy composite with different weight percentage of SiO{sub 2} are investigated using scanning electron microscopy. Two types of curing agent, dimethylbenzanthracene (DMBA) and methyltetrahydrophthalic anhydride (MeTHPA), are individually used for preparing the composites. It is found that the fracture surface morphology of the composite cured by DMBA shows as radial striations, which suggests a rapid brittle fracture mode, while the fracture surface morphology of the composite cured by MeTHPA shows as regularly spaced 'rib' markings, which indicates a stick-slip motion during the fracture process. Furthermore, the uniaxial tensile behavior under constant loading rate and ambient temperature are investigated. It is shown that the elastic modulus of the composite cured by DMBA firstly increases, and then decreases with the mass fraction of nano-SiO{sub 2} particles, but the elongation of the composite cured by MeTHPA is reversed with increasing fraction of nano-SiO{sub 2} particles. For nano-SiO{sub 2}/epoxy composite cured with MeTHPA that possesses a suitable fraction of nano-SiO{sub 2}, an excellent synthetic mechanical property on elastic modulus and elongation is obtained.

  6. Codon 61 mutations in the c-Harvey-ras gene in mouse skin tumors induced by 7,12-dimethylbenz[a]anthracene plus okadaic acid class tumor promoters.

    Science.gov (United States)

    Fujiki, H; Suganuma, M; Yoshizawa, S; Kanazawa, H; Sugimura, T; Manam, S; Kahn, S M; Jiang, W; Hoshina, S; Weinstein, I B

    1989-01-01

    Three okadaic acid class tumor promoters, okadaic acid, dinophysistoxin-1, and calyculin A, have potent tumor-promoting activity in two-stage carcinogenesis experiments on mouse skin. DNA isolated from tumors induced by 7,12-dimethylbenz[a]anthracene (DMBA) and each of these tumor promoters revealed the same mutation at the second nucleotide of codon 61 (CAA----CTA) in the c-Ha-ras gene, determined by the polymerase chain reaction procedure and DNA sequencing. Three potent 12-O-tetradecanoylphorbol-13-acetate (TPA)-type tumor promoters, TPA, teleocidin, and aplysiatoxin, showed the same effects. These results provide strong evidence that this mutation in the c-Ha-ras gene is due to a direct effect of DMBA rather than a selective effect of specific tumor promoters.

  7. Intense Pulsed Light: Friend or Foe? Molecular Evidence to Clarify Doubts.

    Science.gov (United States)

    Ferreira, Liliana; Vitorino, Rui; Neuparth, Maria João; Rodrigues, David; Gama, Adelina; Faustino-Rocha, Ana I; Ferreira, Rita; Oliveira, Paula A

    2018-02-01

    Intense pulsed light (IPL) has been extensively applied in the field of dermatology and aesthetics; however, the long-term consequences of its use are poorly unknown, and to the best of our knowledge there is no study on the effect of IPL in neoplastic lesions. In order to better understand the molecular mechanisms underlying IPL application in the skin, we used an animal model of carcinogenesis obtained by chemical induction with 12-dimethylbenz(a)anthracene (DMBA) and 12-O-tetradecanoylphorbol-13-acetate (TPA). Institute of Cancer Research (ICR) mice were administered DMBA and/or TPA and treated with IPL. Skin was evaluated by histopathology and 2DE-blot-MS/MS analysis. Our data evidenced an inflammatory response and a metabolic remodeling of skin towards a glycolytic phenotype after chronic exposure to IPL, which was accomplished by increased oxidative stress and susceptibility to apoptosis. These alterations induced by IPL were more notorious in the DMBA sensitized skin. Keratins and metabolic proteins seem to be the more susceptible to oxidative modifications that might result in loss of function, contributing for the histological changes observed in treated skin. Data highlight the deleterious impact of IPL on skin phenotype, which justifies the need for more experimental studies in order to increase our understanding of the IPL long-term safety. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  8. Differential tumor biology effects of double-initiation in a mouse skin chemical carcinogenesis model comparing wild type versus protein kinase Cepsilon overexpression mice.

    Science.gov (United States)

    Li, Yafan; Wheeler, Deric L; Ananthaswamy, Honnavara N; Verma, Ajit K; Oberley, Terry D

    2007-12-01

    Our previous studies showed that protein kinase Cepsilon (PKCepsilon) verexpression in mouse skin resulted in metastatic squamous cell carcinoma (SCC) elicited by single 7,12-dimethylbenz(a)anthracene (DMBA)-initiation and 12-O-tetradecanoylphorbol-13-acetate (TPA)-promotion in the absence of preceding papilloma formation as is typically observed in wild type mice. The present study demonstrates that double-DMBA initiation modulates tumor incidence, multiplicity, and latency period in both wild type and PKCepsilon overexpression transgenic (PKCepsilon-Tg) mice. After 17 weeks (wks) of tumor promotion, a reduction in papilloma multiplicity was observed in double- versus single-DMBA initiated wild type mice. Papilloma multiplicity was inversely correlated with cell death indices of interfollicular keratinocytes, indicating decreased papilloma formation was caused by increased cell death and suggesting the origin of papillomas is in interfollicular epidermis. Double-initiated PKCepsilon-Tg mice had accelerated carcinoma formation and cancer incidence in comparison to single-initiated PKCepsilon-Tg mice. Morphologic analysis of mouse skin following double initiation and tumor promotion showed a similar if not identical series of events to those previously observed following single initiation and tumor promotion: putative preneoplastic cells were observed arising from hyperplastic hair follicles (HFs) with subsequent cancer cell infiltration into the dermis. Single-initiated PKCepsilon-Tg mice exhibited increased mitosis in epidermal cells of HFs during tumor promotion.

  9. 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.

  10. Estudo da reação entre polietileno glicol e resina epoxídica na presença de N,N-dimetilbenzilamina Study of the reaction between polyethylene glycol and epoxy resins Using N,N-dimethylbenzylamine as catalyst

    Directory of Open Access Journals (Sweden)

    Mario Zacharuk

    2011-01-01

    Full Text Available Neste trabalho foi estudada a reação entre polietileno glicol (PEG e uma resina epoxídica à base de diglicidil éter de bisfenol A (DGEBA, na presença de N,N-dimetilbenzilamina (DMBA, sendo os produtos desta reação avaliados por espectroscopia no infravermelho (FTIR, espectroscopia de ressonância magnética nuclear de próton (RMN-1H e medidas de viscosidade cone-prato. Amostras curadas com um endurecedor à base de poliamina foram também submetidas a ensaios de tração e calorimetria exploratória diferencial (DSC. Os resultados das análises de viscosidade, FTIR e RMN (1H confirmaram a ocorrência da reação entre grupos epóxi do DGEBA e grupos hidroxila do PEG na presença de DMBA, a 100 ºC. As análises de DSC e os ensaios de tração dos sistemas curados mostram que a reação de DGEBA com PEG gera um material com temperatura de transição vítrea (Tg significativamente menor, em conjunto com o aumento da deformação na ruptura e decréscimo do modulo de elasticidade, quando comparados ao sistema epoxídico de referência (DGEBA.In this work the reaction of polyethylene glycol (PEG and epoxy resin (BADGE in the presence of N,N-dimethylbenzylamine (DMBA was studied. The reaction products were evaluated by infrared spectroscopy (FTIR, nuclear magnetic resonance spectroscopy (NMR and viscosity measurements. Samples cured with a polyamine-based hardener were also submitted to tensile tests and differential scanning calorimetry (DSC. The results of the viscosity analyses, FTIR and RMN (¹H confirmed the reaction between DGEBA epoxy groups and PEG hydroxyl groups in the presence of DMBA, at 100 ºC. DSC analyses and tensile tests of cured systems showed that the reaction of DGEBA with PEG leads to a reduction of Tg, generating a more flexible material.

  11. Protective effect of Ocimum sanctum on 3-methylcholanthrene, 7,12-dimethylbenz(a)anthracene and aflatoxin B1 induced skin tumorigenesis in mice

    Energy Technology Data Exchange (ETDEWEB)

    Rastogi, Shipra; Shukla, Yogeshwer; Paul, Bhola N; Chowdhuri, D Kar; Khanna, Subhash K [Industrial Toxicology Research Centre, Mahatma Gandhi Marg, P.O. Box 80, Lucknow-226001 (India); Das, Mukul [Industrial Toxicology Research Centre, Mahatma Gandhi Marg, P.O. Box 80, Lucknow-226001 (India)

    2007-11-01

    A study on the protective effect of alcoholic extract of the leaves of Ocimum sanctum on 3-mthylcholanthrene (MCA), 7,12-dimethylbenzanthracene (DMBA) and aflatoxin B{sub 1} (AFB{sub 1}) induced skin tumorigenesis in a mouse model has been investigated. The study involved pretreatment of mice with the leaf extract prior to either MCA application or tetradecanoyl phorbol acetate (TPA) treatment in a two-stage tumor protocol viz a viz, DMBA/TPA and AFB1/TPA. The results of the present study indicate that the pretreatment with alcoholic extract of the leaves of O. sanctum decreased the number of tumors in MCA, DMBA/TPA and AFB1/TPA treated mice. The skin tumor induced animals pretreated with alcoholic extract led to a decrease in the expression of cutaneous {gamma}-glutamyl transpeptidase (GGT) and glutathione-S-transferase-P (GST-P) protein. The histopathological examination of skin tumors treated with leaf extract showed increased infiltration of polymorphonuclear, mononuclear and lymphocytic cells, decreased ornithine decarboxylase activity with concomitant enhancement of interleukin-1{beta} (IL-1{beta}) and tumor necrosis factor-{alpha} (TNF-{alpha}) in the serum, implying the in vivo antiproliferative and immunomodulatory activity of leaf extract. The decrease in cutaneous phase I enzymes and elevation of phase II enzymes in response to topical application of leaf extract prior to MCA, AFB1, DMBA/TPA and AFB1/TPA treatment indicate the possibility of impairment in reactive metabolite(s) formation and thereby reducing skin carcinogenicity. Furthermore, pretreatment of leaf extract in the carcinogen induced animals resulted in elevation of glutathione levels and decrease in lipid peroxidation along with heat shock protein expression, indicating a scavenging or antioxidant potential of the extract during chemical carcinogenesis. Thus it can be concluded that leaf extract of O. sanctum provides protection against chemical carcinogenesis in one or more of the

  12. Activation of Akt1 accelerates carcinogen-induced tumorigenesis in mammary gland of virgin and post-lactating transgenic mice

    International Nuclear Information System (INIS)

    Wu, Yanyuan; Kim, Juri; Elshimali, Yayha; Sarkissyan, Marianna; Vadgama, Jaydutt V

    2014-01-01

    Data from in vivo and in vitro studies suggest that activation of Akt regulates cell survival signaling and plays a key role in tumorigenesis. Hence, transgenic mice were created to explore the oncogenic role of Akt1 in the development of mammary tumors. The transgenic mice were generated by expressing myristoylated-Akt1 (myr-Akt1) under the control of the MMTV-LTR promoter. The carcinogen 7, 12 dimethyl-1,2-benzanthracene (DMBA) was used to induce tumor formation. The MMTV driven myr-Akt1 transgene expression was detected primarily in the mammary glands, uterus, and ovaries. The expression level increased significantly in lactating mice, suggesting that the response was hormone dependent. The total Akt expression level in the mammary gland was also higher in the lactating mice. Interestingly, the expression of MMTVmyr-Akt1 in the ovaries of the transgenic mice caused significant increase in circulating estrogen levels, even at the post-lactation stage. Expression of myr-Akt1 in mammary glands alone did not increase the frequency of tumor formation. However, there was an increased susceptibility of forming mammary tumors induced by DMBA in the transgenic mice, especially in mice post-lactation. Within 34 weeks, DMBA induced mammary tumors in 42.9% of transgenic mice post-lactation, but not in wild-type mice post-lactation. The myr-Akt1 mammary tumors induced by DMBA had increased phosphorylated-Akt1 and showed strong expression of estrogen receptor (ERα) and epidermal growth factor receptor (EGFR). In addition, Cyclin D1 was more frequently up-regulated in mammary tumors from transgenic mice compared to tumors from wild-type mice. Overexpression of Cyclin D1, however, was not completely dependent on activated Akt1. Interestingly, mammary tumors that had metastasized to secondary sites had increased expression of Twist and Slug, but low expression of Cyclin D1. In summary, the MMTVmyr-Akt1 transgenic mouse model could be useful to study mechanisms of ER

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  14. Chemopreventive efficacy of betel leaf extract and its constituents on 7,12-dimethylbenz(a)anthracene induced carcinogenesis and their effect on drug detoxification system in mouse skin.

    Science.gov (United States)

    Azuine, M A; Amonkar, A J; Bhide, S V

    1991-04-01

    Effects of topically applied betel leaf extract (BLE) and its constituents. beta-carotene, alpha-tocopherol, eugenol and hydroxychavicol on 7,12-dimethylbenz(a)anthracene (DMBA) induced skin tumors were evaluated in two strains of mice. BLE, beta-carotene and alpha-tocopherol, significantly inhibited the tumor formation by 83, 86, 86% in Swiss mice and 92, 94 and 89% in male Swiss bare mice respectively. Hydroxychavicol showed 90% inhibition in Swiss bare mice at 24 weeks of treatment. Eugenol showed minimal protection in both strains of mice. The mean latency period and survivors in BLE, beta-carotene, alpha-tocopherol and hydroxychavicol treated groups were remarkably high as compared to DMBA alone treated group. Intraperitoneal injection of betal leaf constituents showed a significant effect on both glutathione and glutathione S-transferase levels in the Swiss mouse skin.

  15. Dysregulation of Autophagy Contributes to Anal Carcinogenesis.

    Directory of Open Access Journals (Sweden)

    Evie H Carchman

    Full Text Available Autophagy is an intracellular catabolic process that removes and recycles unnecessary/dysfunctional cellular components, contributing to cellular health and survival. Autophagy is a highly regulated cellular process that responds to several intracellular signals, many of which are deregulated by human papillomavirus (HPV infection through the expression of HPV-encoded oncoproteins. This adaptive inhibitory response helps prevent viral clearance. A strong correlation remains between HPV infection and the development of squamous cell carcinoma (SCC of the anus, particularly in HIV positive and other immunosuppressed patients. We hypothesize that autophagy is inhibited by HPV-encoded oncoproteins thereby promoting anal carcinogenesis (Fig 1.HPV16 transgenic mice (K14E6/E7 and non-transgenic mice (FVB/N, both of which do not spontaneously develop anal tumors, were treated topically with the chemical carcinogen, 7,12-Dimethylbenz[a]anthracene (DMBA, to induce anal cancer. The anuses at different time points of treatment (5, 10, 15 and 20 weeks were analyzed using immunofluorescence (IF for two key autophagy marker proteins (LC3β and p62 in addition to histological grading. The anuses from the K14E6/E7 mice were also analyzed for visual evidence of autophagic activity by electron microscopy (EM. To see if there was a correlation to humans, archival anal specimens were assessed histologically for grade of dysplasia and then analyzed for LC3β and p62 protein content. To more directly examine the effect of autophagic inhibition on anal carcinogenesis, nontransgenic mice that do not develop anal cancer with DMBA treatment were treated with a known pharmacologic inhibitor of autophagy, chloroquine, and examined for tumor development and analyzed by IF for autophagic proteins.Histologically, we observed the progression of normal anoderm to invasive SCC with DMBA treatment in K14E6/E7 mice but not in nontransgenic, syngeneic FVB/N background control mice

  16. Antiproliferative potential of aqueous leaf extract of Mucuna pruriens ...

    African Journals Online (AJOL)

    J.B. Minari

    2016-02-01

    Feb 1, 2016 ... of Mucuna pruriens on DMBA-induced breast cancer in female ... DNA smears obtained from single cell gel electrophoresis (SCGE) suggested ..... sign ifican t reduction. (p. <. 0.01). Valu es carrying superscript. (c) sho wed.

  17. Inhibition of Neoplastic Transformation and Chemically-Induced Skin Hyperplasia in Mice by Traditional Chinese Medicinal Formula Si-Wu-Tang

    Directory of Open Access Journals (Sweden)

    Mandy M. Liu

    2017-03-01

    Full Text Available Exploring traditional medicines may lead to the development of low-cost and non-toxic cancer preventive agents. Si-Wu-Tang (SWT, comprising the combination of four herbs, Rehmanniae, Angelica, Chuanxiong, and Paeoniae, is one of the most popular traditional Chinese medicines for women’s diseases. In our previous studies, the antioxidant Nrf2 pathways were strongly induced by SWT in vitro and in vivo. Since Nrf2 activation has been associated with anticarcinogenic effects, the purpose of this study is to evaluate SWT’s activity of cancer prevention. In the Ames test, SWT demonstrated an antimutagenic activity against mutagenicity induced by the chemical carcinogen 7,12-dimethylbenz(aanthracene (DMBA. In JB6 P+ cells, a non-cancerous murine epidermal model for studying tumor promotion, SWT inhibited epidermal growth factor (EGF-induced neoplastic transformation. The luciferase reporter gene assays demonstrated that SWT suppressed EGF-induced AP-1 and TNF-α-induced NF-κB activation, which are essential factors involved in skin carcinogenesis. In a DMBA-induced skin hyperplasia assay in ‘Sensitivity to Carcinogenesis’ (SENCAR mice, both topical and oral SWT inhibited DMBA-induced epidermal hyperplasia, expression of the proliferation marker Proliferating cell nuclear antigen (PCNA, and H-ras mutations. These findings demonstrate, for the first time, that SWT prevents tumor promoter and chemical-induced carcinogenesis in vitro and in vivo, partly by inhibiting DNA damage and blocking the activation of AP-1 and NF-κB.

  18. A Study on the Pre-and Post-irradiation Effect of Blood Vessels in the Experimentally Induced Tongue Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Tae; Park, Tae Won [Dept. of Oral Radiology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    1990-02-15

    The author observed the changes of vasculature of pre-and post-irradiation on DMBA induced rat tongue cancer. The study was performed by using vascular corrosion resin casting, and scanning electron microscopy. The results were as follows. 1. The capillaries runned parallely and formed bundles and, sometimes, plexus. The endothelial cells were arranged regularly and small pores were observed. 2. In irradiated normal tongue the capillaries were curved slightly and formed plexus on initial day of post-irradiation. On third day the capillaries and capillary pores were dilated and the endothelial cell arrangement was irregular. The effects of irradiation were gradually increased from initial to the 3rd day, though it was decreased after 7th day. 3. The vasculature of DMBA induced tongue cancer group were very irregular, and large avascular lesions were formed according to the cancer necrosis or tumor cell nest and the vasculature was narrowed and paralleled around the avascular lesion by compression of cancer cell nest. The vascular wall was roughened and dilated, forming club shaped or varix. 4. The vessels were curved and formed reticular network in irradiated DMBA induced tongue carinoma group. The free end of newly formed capillaries had regular width, and also irregular club shaped or aneurysmal dilation were observed. The vascular structures were destroyed and vessels were fused in tumor necrosis lesion. The radiation effects were marked on the first and third day of irradiation and the effects were decreased after seventh day and showed capillary regeneration.

  19. Is Peripheral Benzodiazepine Receptor (PBR) Gene Expression Involved in Breast Cancer Suppression by Dietary Soybean Protein

    National Research Council Canada - National Science Library

    Das, Salil

    2004-01-01

    ...% casein and those of groups 3 and 4 received same diet containing 20% soybean protein. Animals of groups 2 and 4 received DMBA in sesame oil by gavage (15 mg per animal). Control animals (groups 1 and 3...

  20. Utilizing nonlinear optical microscopy to investigate the development of early cancer in nude mice in vivo

    Science.gov (United States)

    Wang, Chun-Chin; Li, Feng-Chieh; Lin, Sung-Jan; Lo, Wen; Dong, Chen-Yuan

    2007-07-01

    In this investigation, we used in vivo nonlinear optical microscopy to image normal and carcinogen DMBA treated skin tissues of nude mice. We acquired two-photon autofluroescence and second harmonic generation (SHG) images of the skin tissue, and applied the ASI (Autofluorescence versus SHG Index) to the resulting image. This allows us to visualize and quantify the interaction between mouse skin cells and the surrounding connective tissue. We found that as the imaging depth increases, ASI has a different distribution in the normal and the treated skin tissues. Since the DMBA treated skin eventually became squamous cell carcinoma (SCC), our results show that the physiological changes to mouse skin en route to become cancer can be effectively tracked by multiphoton microscopy. We envision this approach to be effective in studying tumor biology and tumor treatment procedures.

  1. Effect of rosella (Hibiscus sabdariffa L) extract on glutathione-S ...

    African Journals Online (AJOL)

    reactivities are reduced by electron donation from other ... release various enzymes into the blood. These enzymes such .... reaction buffer, 1 µL of ribolock RNase inhibitor,. 2 μL of 10 mM .... DMBA has adverse effect on GST gene expression.

  2. Studying skin tumourigenesis and progression in immunocompetent hairless SKH1-hr mice using chronic 7,12-dimethylbenz(a)anthracene topical applications to develop a useful experimental skin cancer model

    NARCIS (Netherlands)

    Thomas, Giju; Tuk, Bastiaan; Song, Ji-Ying; Truong, Hoa; Gerritsen, Hans C.; de Gruijl, Frank R.; Sterenborg, Henricus J. C. M.

    2017-01-01

    Previous studies have established that 7,12-dimethylbenz(a)anthracene (DMBA) can initiate skin tumourigenesis in conventional furred mouse models by acting on hair follicle stem cells. However, further cancer progression depends on repeated applications of tumour promoter agents. This study

  3. Emodin downregulates cell proliferation markers during DMBA ...

    African Journals Online (AJOL)

    Background: Cell-cycle disruption is the major characteristic features of neoplastic transformation and the status of cell-cycle regulators can thus be utilized to assess the prognostic significance in patients with cancer. The PCNA, cyclin D1, CDK4, CDK6 and survivin expression in the buccal mucosa was utilized to evaluate ...

  4. Interacciones genotóxicas de mutágenos en mezclas binarias mediante ensayo cometa alcalino en linfocitos humanos

    Directory of Open Access Journals (Sweden)

    Isabel C. Ortiz

    2012-05-01

    Full Text Available Introducción. Los mutágenos contenidos en mezclas complejas presentan interacciones desinergismo, aditivas o antagónicas. Se han desarrollado enfoques experimentales que permitandilucidar el responsable de las interacciones en la mezcla. Objetivo. Desarrollar un diseño experimental para comprender los procesos que se llevan a caboentre los compuestos presentes en las mezclas complejas. Materiales y métodos. Se expusieron linfocitos humanos a mezclas binarias de mutágenos B[a]P,DMBA, Trp-P-1 y MX durante una hora, con activación metabólica y sin ella. La viabilidad se evaluócon azul de tripano y, la genotoxicidad, con cometa alcalino. Resultados. Ningún hidrocarburo tuvo efecto con furanona. Con S9 y sin él, se observó que sepresentaban interacciones tóxicas entre hidrocarburos. Se observó sinergismo sin S9 entre B[a]P yTrp-P-1 y, con actividad metabólica, entre DMBA y Trp-P-1. Sin S9 se observó interacción antagónicaentre Trp-P-1 y DMBA y, con S9, entre Trp-P-1 y MX y entre MX y DMBA. Se observó un incrementodependiente de la dosis en la longitud de la cola. Hubo daño genotóxico medio y aumento de lascélulas dañadas. Para todas las mezclas se pudo determinar la concentración mínima en la que seobservaban efectos adversos y solo para algunas se determinó la concentración máxima en la cual nose observaron efectos adversos. Conclusión. Se hace un aporte para comprender los procesos que ocurren cuando en una mezclahay presentes, al menos, dos mutágenos y se valida un modelo de análisis que permite dilucidar elcompuesto que tiene efecto sobre otro. También, se demostró que según el tipo de compuestos en lamezcla, se tendrá o no un umbral de riesgo.   doi: http://dx.doi.org/10.7705/biomedica.v32i3.739

  5. Rac1 is crucial for Ras-dependent skin tumor formation by controlling Pak1-Mek-Erk hyperactivation and hyperproliferation in vivo

    DEFF Research Database (Denmark)

    Wang, Z; Pedersen, Esben Ditlev Kølle; Basse, A

    2010-01-01

    that Rac1 is essential for DMBA/TPA-induced skin tumor formation. This corresponded to a decreased keratinocyte hyperproliferation, although apoptosis was not detectably altered. Activated Rac1 promoted Erk-dependent hyperproliferation by Pak1-mediated Mek activation independent of Mek1 phosporylation...

  6. Evaluation of protective effect of myricetin, a bioflavonoid in dimethyl benzanthracene-induced breast cancer in female Wistar rats

    Directory of Open Access Journals (Sweden)

    J K Jayakumar

    2014-01-01

    Full Text Available Background: Breast cancer is one of the most common cancers worldwide. Alarmingly, the incidence of breast cancer is rising rapidly in India. Aim: The present research was focused to assess the role of myricetin; a bioflavonoid in 7,12-dimethylbenzanthracene (DMBA-induced breast cancer in female Wistar rats. Materials and Methods: A total of 36 female Wistar rats (total 6 groups, n = 6 per group 6 - 8 weeks old, weighing 150 gm were used in the study. DMBA was given at the dose of 7.5 mg/kg subcutaneously in the mammary region once a week for 4 consecutive weeks in group 2. Vincristine was given in the dose of 500 μg/kg intraperitonially every week for 4 consecutive weeks in group 3. Myricetin was given orally in a dose of 50, 100, and 200 mg/kg in group 4, 5, and 6 respectively. The statistical significance of the data was determined using one way analysis of variance and Duncan′s multiple range test. Results: The result showed that myricetin increased the antioxidant levels in plasma, erythrocyte lysate, and breast tissue and was effective in preventing the oxidative damage induced by the carcinogen DMBA. Myricetin 50, 100, and 200 mg/kg/oral for 120 days treated animal resulted comparable results to that of standard vincristine and control groups. Conclusions: Myricetin was found to be either equieffective or more effective than vincristine in all the parameters studied. Myricetin proved the capacity of flavonols to act as antioxidant in cells represents a potential treatment in the field of oncology.

  7. In vitro early changes in intercellular junctions by treatment with a chemical carcinogen.

    Science.gov (United States)

    Tachikawa, T; Kohno, Y; Matsui, Y; Yoshiki, S

    1986-06-01

    To examine early intercellular junction changes caused by treatment with 9,10-dimethyl-1,2-benzanthracene (DMBA), rat lingual epithelium was cultivated in isolation and observed by electrophysiological, freeze-fracture and whole-mount electron microscopy. Electrophysiological measurements showed a transient decrease in membrane potential of -10.2 mV 6 h after the treatment. It returned to almost the same level as that of the control group 1 day later. Six hours after treatment, input resistance decreased rapidly to 5.3 M omega but increased to 18.0 M omega 12 h after treatment. Transient reduction of input resistance and membrane potential occurred prior to the decrease in the coupling ratio 6 h after treatment with DMBA. In freeze-fracture replicas, the number of gap junctions decreased by approximately 45% of the control value 6 h after treatment with DMBA. At 12 h and thereafter, the number and area of gap junctions subsequently decreased by 60-80% of the control value. Alterations in the number and area of desmosomes were similar to those of the gap junctions. The formation of epithelial cytoskeletons, partially devoid of the 2-4 and 5-8 nm filaments was also observed. A decrease in the density of filament networks beneath the plasma membranes was especially apparent. Treatment with a carcinogen brought about morphological cellular changes as early as 6 h after treatment, and such early changes might trigger metabolic cellular abnormalities. Affected cells appear to move away from normal cells in a process of repeated destruction and revision of intercellular junctions, and cytoskeletons.

  8. Inhibition of carcinogen induced c-Ha-ras and c-fos proto-oncogenes expression by dietary curcumin

    Directory of Open Access Journals (Sweden)

    Lipigorngoson Suwiwek

    2001-01-01

    Full Text Available Abstract Background We investigated the chemopreventive action of dietary curcumin on 7,12-dimethylbenz(aanthracene (DMBA-initiated and 12,0-tetradecanoylphorbol-13-acetate (TPA-promoted skin tumor formation in Swiss albino mice. Curcumin, a yellow coloring matter isolated from roots of Curcuma longa Linn, is a phenolic compound possessing antioxidant, free radical scavenger, and antiinflammatory properties. It has been shown by previously reported work that TPA-induced skin tumors were inhibited by topical application of curcumin, and curcumin has been shown to inhibit a variety of biological activities of TPA. Topical application of curcumin was reported to inhibit TPA-induced c-fos, c-jun and c-myc gene expression in mouse skin. This paper reports the effects of orally administered curcumin, which was consumed as a dietary component at concentrations of 0.2 % or 1 %, in ad libitum feeding. Results Animals in which tumors had been initiated with DMBA and promoted with TPA experienced significantly fewer tumors and less tumor volume if they ingested either 0.2% or 1% curcumin diets. Also, the dietary consumption of curcumin resulted in a significantly decreased expression of ras and fos proto-oncogenes in the tumorous skin, as measured by enhanced chemiluminesence Western blotting detection system (Amersham. Conclusions Whereas earlier work demonstrated that topical application of curcumin to mouse skin inhibited TPA-induced expression of c-fos, c-jun and c-myc oncogenes, our results are the first to show that orally consumed curcumin significantly inhibited DMBA- and TPA-induced ras and fos gene expression in mouse skin.

  9. Inhibition of carcinogen induced c-Ha-ras and c-fos proto-oncogenes expression by dietary curcumin

    International Nuclear Information System (INIS)

    Limtrakul, Porn-ngarm; Anuchapreeda, Songyot; Lipigorngoson, Suwiwek; Dunn, Floyd W

    2001-01-01

    We investigated the chemopreventive action of dietary curcumin on 7,12-dimethylbenz(a)anthracene (DMBA)-initiated and 12,0-tetradecanoylphorbol-13-acetate (TPA)-promoted skin tumor formation in Swiss albino mice. Curcumin, a yellow coloring matter isolated from roots of Curcuma longa Linn, is a phenolic compound possessing antioxidant, free radical scavenger, and antiinflammatory properties. It has been shown by previously reported work that TPA-induced skin tumors were inhibited by topical application of curcumin, and curcumin has been shown to inhibit a variety of biological activities of TPA. Topical application of curcumin was reported to inhibit TPA-induced c-fos, c-jun and c-myc gene expression in mouse skin. This paper reports the effects of orally administered curcumin, which was consumed as a dietary component at concentrations of 0.2 % or 1 %, in ad libitum feeding. Animals in which tumors had been initiated with DMBA and promoted with TPA experienced significantly fewer tumors and less tumor volume if they ingested either 0.2% or 1% curcumin diets. Also, the dietary consumption of curcumin resulted in a significantly decreased expression of ras and fos proto-oncogenes in the tumorous skin, as measured by enhanced chemiluminesence Western blotting detection system (Amersham). Whereas earlier work demonstrated that topical application of curcumin to mouse skin inhibited TPA-induced expression of c-fos, c-jun and c-myc oncogenes, our results are the first to show that orally consumed curcumin significantly inhibited DMBA- and TPA-induced ras and fos gene expression in mouse skin

  10. Potential effects of the herbicide Diuron on mammary and urinary bladder two-stage carcinogenesis in a female Swiss mouse model.

    Science.gov (United States)

    de Moura, Nelci Antunes; Grassi, Tony Fernando; Rodrigues, Maria Aparecida Marchesan; Barbisan, Luís Fernando

    2010-02-01

    The potential promoting effect of Diuron was investigated in a mouse model of mammary and urinary bladder carcinogenesis induced by 7,12-dimethylbenz(a)anthracene (DMBA) and N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN). Four-week old female Swiss mice were allocated to five groups: Groups G1-G3 received DMBA (5 x 1.5 mg/mouse) and BBN (8 x 7.5 mg/mouse) and G4 and G5 groups received only vehicles during the first 6 weeks. At week 7, G1 and G5 groups received basal diet and G2, G3 and G4 groups were fed a diet containing Diuron at 1,250, 2,500 and 2,500 ppm, respectively, during 13 weeks. At week 20, the animals were euthanized and the gross tumors were registered. Mammary glands and urinary bladder were processed for histopathological analysis. Samples from non-tumor areas were evaluated for cell proliferation by 5-bromodeoxyuridine labeling index (BrdU-LI%) and apoptosis. Dietary treatment with Diuron at 1,250 and 2,500 ppm significantly increased BrdU-LI% (P Diuron 2,500 ppm (G3). In contrast, in the mammary gland, Diuron feeding for 13 weeks did not significantly alter cell proliferation and apoptosis indexes or the incidence of hyperplastic lesions or neoplasms in the DMBA/BBN-initiated groups. These findings suggest that Diuron is a promoting agent to the urinary bladder but not to the mammary gland in female Swiss mice submitted to a medium-term two-stage carcinogenesis bioassay.

  11. Tumor-specific antivascular effect of TZT-1027 (Soblidotin) elucidated by magnetic resonance imaging and confocal laser scanning microscopy

    International Nuclear Information System (INIS)

    Natsume, Tsugitaka; Watanabe, Junichi; Kobayashi, Motohiro; Ogawa, Kenji; Yasumura, Kazuhiko

    2007-01-01

    TZT-1027 (soblidotin), an antimicrotubule agent, has previously been evaluated in terms of its antivascular effects. In this study, Evans blue perfusion, magnetic resonance imaging (MRI), and confocal laser scanning microscopy (CLSM) were utilized to further elucidate the antivascular effect of TZT-1027 in female nude mice and rats bearing human breast tumor MX-1, as well as in female Sprague-Dawley rats that developed breast tumors induced by dimethylbenz(a)anthracene (DMBA). Therapeutic doses of TZT-1027 caused nearly complete regression of implanted MX-1 tumors in nude mice and rats as well as DMBA-induced tumors in rats. The perfusion in MX-1 tumor implanted in nude mice was drastically reduced within 30 min after TZT-1027 administration and was completely inhibited after 6 h or more, although not reduced in normal tissue of kidney. The study using MRI demonstrated that rich blood flow within tumors was remarkably reduced 1-3 h after TZT-1027 administration both in nude rats bearing MX-1 tumors and in rats with DMBA-induced tumors. Furthermore, the study with CLSM in nude mice bearing MX-1 tumors revealed a disruption of tumor microvessels at 1 h and a destruction of tumor microvessel network at 3 h after TZT-1027 administration. In contrast, these types of vascular disorders were not observed in heart and kidney. These results suggest that TZT-1027 specifically damages tumor vasculatures, leading to extensive tumor necrosis within tolerable dose range, and confirms earlier observations that TZT-1027 exerts a considerable antivascular effect in addition to an excellent cytotoxic effect. (author)

  12. Antigenotoxic Effect Of Ferulic Acid In 7,12-Dimethyl Benz(A ...

    African Journals Online (AJOL)

    The antigenotoxic effect of ferulic acid was carried out by evaluating the cytogenetic markers, the micronuclei frequency and chromosomal aberrations, in the bone marrow of hamsters in 7,12- dimethylbenz(a)anthracene (DMBA) induced genotoxicity. Genotoxicity was induced in experimental hamsters by single ...

  13. Anti-tumor activity of tetrodotoxin extracted from the Masked Puffer ...

    African Journals Online (AJOL)

    as demonstrated by trypan blue stain (d and f) and after treatment with Annexin V stain (e & g) (X1000). Notice ... hair erection and loss of appetite. ..... effect of vitamin A against carcinogenic effect of 7, 12- DMBA on the liver of albino rat. Egypt.

  14. Multiple sclerosis in Latter Day Saints (Mormons).

    Science.gov (United States)

    Hawkes, C H; Ramkumar, N; Baker, R; Lyon, J L

    2007-04-01

    Compliant members of the Church of Jesus Christ of Latter Day Saints (LDS, Mormons) have a low incidence of heart and lung disease that may relate to their healthy life style. We wished to determine whether multiple sclerosis (MS) was less frequent in this religious body. To ascertain this, diagnostic and treatment coding records were accessed from the Deseret Mutual Benefit Administrators (DMBA) for the 6 year period 1997-2002. DMBA is a medical insurance company that provides medical insurance to all employees of LDS Church in the US. This information was combined with prescribing records for disease modifying treatment, principally beta-interferon and Copaxone which are medications specific to MS. Using various search strategies we derived an approximate MS prevalence of 45-64/100,000. Comparison with MS rates from Utah and other states of comparable latitude suggest that strict LDS have an MS prevalence that is lower than expected and may reflect their healthy life style.

  15. Rapid promotion and progression of fibrovascular polyps by inflammation and/or hyperplasia in hamster check pouch: implications for carcinogenesis assay.

    Science.gov (United States)

    McGaughey, C; Jensen, J L

    1983-03-01

    Tumor initiation by topical application of 7,12-dimethylbenz[a]anthracene (DMBA) in dimethyl sulfoxide (DMSO) followed by topical application of retinyl acetate (RA), ethylphenylpropiolate, or acetic acid in DMSO at inflammatory and hyperplasiogenic dose regimens caused the rapid promotion of fibrovascular polyps with dysplastic epithelium in hamster cheek pouch. Such lesions did not occur in control animals initiated with DMBA followed by application of DMSO only, where inflammation was also minimal. At the dose regimen employed, RA caused obvious cytotoxicity and tissue destruction. With EPP and AA, there was no histological evidence of tissue destruction. At dose regimens resulting in minimal inflammation and no apparent cytotoxicity, RA promoted almost no polyps, but a higher yield of other tumor types. Thus, inflammation and/or hyperplasia apparently exerted a strong polyp-promoting and progressive influence. This and other differences between the tumorigenic responses of hamster-pouch mucosa and mouse skin suggest that the former supplement the latter in carcinogenic risk assessment.

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

    Science.gov (United States)

    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.

  17. Early-in-life dietary zinc deficiency and supplementation and mammary tumor development in adulthood female rats.

    Science.gov (United States)

    da Silva, Flávia R M; Grassi, Tony F; Zapaterini, Joyce R; Bidinotto, Lucas T; Barbisan, Luis F

    2017-06-01

    Zinc deficiency during pregnancy and postnatal life can adversely increase risk of developing human diseases at adulthood. The present study was designed to evaluate whether dietary zinc deficiency or supplementation during the pregnancy, lactation and juvenile stages interferes in the development of mammary tumors induced by 7,12-dimethylbenzanthracene (DMBA) in female Sprague-Dawley (SD) rats. Pregnant female SD rats were allocated into three groups: zinc-adequate diet (ZnA - 35-mg/kg chow), zinc-deficient diet (ZnD - 3-mg/kg chow) or zinc-supplemented diet (ZnS - 180-mg/kg chow) during gestational day 10 (GD 10) until the litters' weaning. Female offspring received the same diets as their dams until postnatal day (PND) 51. At PND 51, the animals received a single dose of DMBA (50 mg/kg, ig) and zinc-adequate diets. At PND 180, female were euthanized, and tumor samples were processed for histological evaluation and gene expression microarray analysis. The ZnD induced a significant reduction in female offspring body weight evolution and in mammary gland development. At late in life, the ZnD or ZnS did not alter the latency, incidence, multiplicity, volume or histological types of mammary tumors in relation to the ZnA group. However, the total tumor number in ZnS group was higher than in ZnA group, accompanied by distinct expression of 4 genes up- and 15 genes down-regulated. The present findings indicate that early-in-life dietary zinc supplementation, differently to zinc deficiency, has a potential to modify the susceptibility to the development of mammary tumors induced by DMBA. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Regulation of p53, nuclear factor κB and cyclooxygenase-2 expression by bromelain through targeting mitogen-activated protein kinase pathway in mouse skin

    International Nuclear Information System (INIS)

    Kalra, Neetu; Bhui, Kulpreet; Roy, Preeti; Srivastava, Smita; George, Jasmine; Prasad, Sahdeo; Shukla, Yogeshwer

    2008-01-01

    Bromelain is a pharmacologically active compound, present in stems and immature fruits of pineapples (Ananas cosmosus), which has been shown to have anti-edematous, anti-inflammatory, anti-thrombotic and anti-metastatic properties. In the present study, antitumorigenic activity of bromelain was recorded in 7,12-dimethylbenz(a)anthracene (DMBA)-initiated and 12-O-tetradecanoylphorbol-13-acetate (TPA)-promoted 2-stage mouse skin model. Results showed that bromelain application delayed the onset of tumorigenesis and reduced the cumulative number of tumors, tumor volume and the average number of tumors/mouse. To establish a cause and effect relationship, we targeted the proteins involved in the cell death pathway. Bromelain treatment resulted in upregulation of p53 and Bax and subsequent activation of caspase 3 and caspase 9 with concomitant decrease in antiapoptotic protein Bcl-2 in mouse skin. Since persistent induction of cyclooxygenase-2 (Cox-2) is frequently implicated in tumorigenesis and is regulated by nuclear factor-kappa B (NF-κB), we also investigated the effect of bromelain on Cox-2 and NF-κB expression. Results showed that bromelain application significantly inhibited Cox-2 and inactivated NF-κB by blocking phosphorylation and subsequent degradation of IκBα. In addition, bromelain treatment attenuated DMBA-TPA-induced phosphorylation of extracellular signal-regulated protein kinase (ERK1/2), mitogen-activated protein kinase (MAPK) and Akt. Taken together, we conclude that bromelain induces apoptosis-related proteins along with inhibition of NF-κB-driven Cox-2 expression by blocking the MAPK and Akt/protein kinase B signaling in DMBA-TPA-induced mouse skin tumors, which may account for its anti-tumorigenic effects

  19. Aryl hydrocarbon receptor (AhR agonists suppress interleukin-6 expression by bone marrow stromal cells: an immunotoxicology study

    Directory of Open Access Journals (Sweden)

    Schlezinger Jennifer J

    2003-12-01

    Full Text Available Abstract Background Bone marrow stromal cells produce cytokines required for the normal growth and development of all eight hematopoietic cell lineages. Aberrant cytokine production by stromal cells contributes to blood cell dyscrasias. Consequently, factors that alter stromal cell cytokine production may significantly compromise the development of normal blood cells. We have shown that environmental chemicals, such as aromatic hydrocarbon receptor (AhR agonists, suppress B lymphopoiesis by modulating bone marrow stromal cell function. Here, we extend these studies to evaluate the potential for two prototypic AhR agonists, 7,12-dimethylbenz [a]anthracene (DMBA and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, to alter stromal cell cytokine responses. Methods Bone marrow stromal cells were treated with AhR agonists and bacterial lipopolysaccharide (LPS to mimic innate inflammatory cytokine responses and to study the effects of AhR ligands on those responses. Steady state cytokine RNA levels were screened by RNAse protection assays (RPA and quantified by real-time PCR. Cytokine (IL-6 protein production was measured by ELISA. NF-κB EMSAs were used to study IL-6 transcriptional regulation. Results RPAs indicated that AhR+ bone marrow stromal cells consistently up-regulated genes encoding IL-6 and LIF in response to LPS, presumably through activation of Toll-like receptor 4. Pre-treatment with low doses of DMBA or TCDD selectively abrogated IL-6 gene induction but had no effect on LIF mRNA. Real-time-PCR indicated a significant inhibition of IL-6 mRNA by AhR ligands within 1 hour of LPS challenge which was reflected in a profound down-regulation of IL-6 protein induction, with DMBA and TCDD suppressing IL-6 levels as much as 65% and 88%, respectively. This potent inhibitory effect persisted for at least 72 hours. EMSAs measuring NF-κB binding to IL-6 promoter sequences, an event known to induce IL-6 transcription, indicated a significant decrease in

  20. Disposition of allylic oxidation pathway metabolites of racemic hexobarbital in the rat

    NARCIS (Netherlands)

    Van der Graaff, M; Vermeulen, N P; Vinks, M H; Breimer, D D

    1986-01-01

    The pharmacokinetics in blood of the major metabolites of hexobarbital (HB), 3'-hydroxyhexobarbital (OH-HB) and 3'-ketohexobarbital (K-HB) were studied in rats. In addition urinary excretion of OH-HB and K-HB and 1,5-dimethylbarbituric acid (DMBA) was determined. Half-lives of OH-HB and K-HB were

  1. Protective role of Withaferin-a on red blood cell integrity during 7,12 ...

    African Journals Online (AJOL)

    The protective effect of Withaferin-A was assessed by measuring the status of glycoconjugates, membrane bound enzyme activity and red blood cell osmotic fragility. Oral squamous cell carcinoma was induced in the buccal pouch of Syrian golden hamsters by painting with 0.5% DMBA in liquid paraffin thrice a week for 14 ...

  2. Hemin inhibits cyclooxygenase-2 expression through nuclear factor-kappa B activation and ornithine decarboxylase expression in 12-O-tetradecanoylphorbol-13-acetate-treated mouse skin

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Hee; Lee, Chang Ki [Department of Oral Biology, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Oral Cancer Research Institute, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Hwang, Young Sun [Department of Applied Life Science and Brain Korea 21 Project, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Park, Kwang-Kyun [Department of Oral Biology, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Department of Applied Life Science and Brain Korea 21 Project, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Chung, Won-Yoon [Department of Oral Biology, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Department of Applied Life Science and Brain Korea 21 Project, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of)], E-mail: wychung@yuhs.ac

    2008-07-03

    Inflammation induced by various stimuli has been found to be associated with increased risk for most types of human cancer. Inflammation facilitates the initiation of normal cells, as well as the growth of initiated cells and their progression to malignancy through production of proinflammatory cytokines and diverse reactive oxygen/nitrogen species. These also activate the signaling molecules that are involved in inflammation and carcinogenesis. Our previous studies have demonstrated that hemin inhibited 7,12-dimethylbenz[a]anthracene (DMBA)-induced bacterial mutagenesis and oxidative DNA damage, reduced the level of DNA-DMBA adduct and 12-O-tetradecanoylphorobl-13-acetate (TPA)-induced tumor formation in DMBA-initiated ICR mouse skin, and inhibited myeloperoxidase and ornithine decarboxylase (ODC) activity and H{sub 2}O{sub 2} formation in TPA-treated mouse skin. In the present study, to further elucidate the molecular mechanisms underlying the chemopreventive activity of hemin, its effect on the expression of ODC and cyclooxygenase (COX)-2, and the activation of nuclear factor-kappa B (NF-{kappa}B) and mitogen-activated protein kinases (MAPKs) regulating these proteins were explored in mouse skin with TPA-induced inflammation. Topically applied hemin inhibited ear edema and epidermal thickness in mice treated with TPA. Pretreatment with hemin reduced the expression of ODC and COX-2, and also reduced NF-{kappa}B activation in TPA-stimulated mouse skin. In addition, hemin suppressed the TPA-induced activation of extracellular signal-regulated protein kinase (ERK) and p38 MAPK in a dose-dependent manner. Taken together, hemin inhibited TPA-induced COX-2 expression by altering NF-{kappa}B signaling pathway via ERK and p38 MAPK, as well as TPA-induced ODC expression in mouse skin. Thereby, hemin may be an attractive candidate for a chemopreventive agent.

  3. Mouse breast cancer model-dependent changes in metabolic syndrome-associated phenotypes caused by maternal dioxin exposure and dietary fat

    Science.gov (United States)

    La Merrill, Michele; Baston, David S.; Denison, Michael S.; Birnbaum, Linda S.; Pomp, Daniel; Threadgill, David W.

    2009-01-01

    Diets high in fat are associated with increased susceptibility to obesity and metabolic syndrome. Increased adipose tissue that is caused by high-fat diets (HFD) results in altered storage of lipophilic toxicants like 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), which may further increase susceptibility to metabolic syndrome. Because both TCDD and HFD are associated with increased breast cancer risk, we examined their effects on metabolic syndrome-associated phenotypes in three mouse models of breast cancer: 7,12-dimethylbenz[a]anthracene (DMBA), Tg(MMTV-Neu)202Mul/J (HER2), and TgN(MMTV-PyMT)634Mul/J (PyMT), all on an FVB/N genetic background. Pregnant mice dosed with 1 μg/kg of TCDD or vehicle on gestational day 12.5 were placed on a HFD or low-fat diet (LFD) at parturition. Body weights, percent body fat, and fasting blood glucose were measured longitudinally, and triglycerides were measured at study termination. On HFD, all cancer models reached the pubertal growth spurt ahead of FVB controls. Among mice fed HFD, the HER2 model had a greater increase in body weight and adipose tissue from puberty through adulthood compared with the PyMT and DMBA models. However, the DMBA model consistently had higher fasting blood glucose levels than the PyMT and HER2 models. TCDD only impacted serum triglycerides in the PyMT model maintained on HFD. Because the estrogenic activity of the HFD was three times lower than that of the LFD, differential dietary estrogenic activities did not drive the observed phenotypic differences. Rather, the HFD-dependent changes were cancer model dependent. These results show that cancer models can have differential effects on metabolic syndrome-associated phenotypes even before cancers arise. PMID:18840765

  4. Experimental skin carcinoma by UVB application

    Directory of Open Access Journals (Sweden)

    Andrada Iftode

    2016-12-01

    Full Text Available OBJECTIVES AND BACKGROUND The aim of this research study was to evaluate the harmful effects at skin level induced by concomitant and repeated exposure to three toxic agents: UVB radiation, DMBA and TPA. MATERIALS AND METHODS Experimental mice were divided in thw following groups (n=5 mice/group: group 1 – healthy mice, group 2 – mice exposed to UVB – radiation and topical administration of acetone and group 3 – mice exposed to UVB – radiation and topical application of DMBA and TPA solutions (phase I - double tumor initiation and phase II - tumor promotion. RESULTS Application of these compounds led to the development of skin papilloma and to significant changes in skin parameters. CONCLUSIONS The barrier function of the skin was degraded in UVB exposed mice. DMBA and TPA depended on carcinogens schedule and corelated with skin carcinoma. Graphical abstract: Schematic protocol of experimental skin carcinoma REFERENCES 1. Lee Ja, Ko Jh, Jung Bg, Kim Th, Hong Ji, Park Ys, Lee Bj. Fermented Prunus mume with Probiotics Inhibits 7,12- Dimethylbenz[a]anthracene and 12-OTetradecanoyl phorbol-13-acetate Induced Skin Carcinogenesis through Alleviation of Oxidative Stress. Asian Pac J Cancer Prev. 2013;14:2973-2978. 2. Firooz A, Sadr B, Babakoohi S, Sarraf-Yazdy M, Fanian F, Kazerouni-Timsar A, NassiriKashani M, Naghizadeh MM, Dowlati Y. Variation of Biophysical Parameters of the Skin with Age, Gender, and Body Region. Scientific World Journal. 2012; doi.org/10.1100/2012/386936 3. Gheorgheosu (Coricovac D, Borcan F, Balasz NI, Soica C, Simu G, Kemeny L, Dehelean CA. Evaluation of skin parameters in C57BL/6J mice exposed to chemical and environmental factors using non-invasive methods. J Agroalim Proc Technol. 2014;20:14-20.

  5. Hemin inhibits cyclooxygenase-2 expression through nuclear factor-kappa B activation and ornithine decarboxylase expression in 12-O-tetradecanoylphorbol-13-acetate-treated mouse skin

    International Nuclear Information System (INIS)

    Park, Jae Hee; Lee, Chang Ki; Hwang, Young Sun; Park, Kwang-Kyun; Chung, Won-Yoon

    2008-01-01

    Inflammation induced by various stimuli has been found to be associated with increased risk for most types of human cancer. Inflammation facilitates the initiation of normal cells, as well as the growth of initiated cells and their progression to malignancy through production of proinflammatory cytokines and diverse reactive oxygen/nitrogen species. These also activate the signaling molecules that are involved in inflammation and carcinogenesis. Our previous studies have demonstrated that hemin inhibited 7,12-dimethylbenz[a]anthracene (DMBA)-induced bacterial mutagenesis and oxidative DNA damage, reduced the level of DNA-DMBA adduct and 12-O-tetradecanoylphorobl-13-acetate (TPA)-induced tumor formation in DMBA-initiated ICR mouse skin, and inhibited myeloperoxidase and ornithine decarboxylase (ODC) activity and H 2 O 2 formation in TPA-treated mouse skin. In the present study, to further elucidate the molecular mechanisms underlying the chemopreventive activity of hemin, its effect on the expression of ODC and cyclooxygenase (COX)-2, and the activation of nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) regulating these proteins were explored in mouse skin with TPA-induced inflammation. Topically applied hemin inhibited ear edema and epidermal thickness in mice treated with TPA. Pretreatment with hemin reduced the expression of ODC and COX-2, and also reduced NF-κB activation in TPA-stimulated mouse skin. In addition, hemin suppressed the TPA-induced activation of extracellular signal-regulated protein kinase (ERK) and p38 MAPK in a dose-dependent manner. Taken together, hemin inhibited TPA-induced COX-2 expression by altering NF-κB signaling pathway via ERK and p38 MAPK, as well as TPA-induced ODC expression in mouse skin. Thereby, hemin may be an attractive candidate for a chemopreventive agent

  6. Influence of ionizing radiation and 7,12-dimethylbenz(a)anthracene on the expression of mammary ductal dysplasia in mice

    International Nuclear Information System (INIS)

    Ethier, S.P.

    1982-01-01

    These studies were undertaken to determine if altered growth potential of mammary epithelial cells could be detected in outgrowths derived from monodispersed mammary cells of virgin female BALB/c mice previously exposed to ionizing radiation or 7,12-dimethylbenz(a)anthracene (DMBA). Monodispersed mammary cells were obtained by enzymatic dissociation of mammary tissues of 12-week-old virgin female BALB/c mice. Twenty-four hours prior to cell dissociation, donor animals were exposed to either γ-ray irradiation or DMBA, while control donors were untreated. Mammary outgrowths were then derived from the donor cells by injecting either 10 5 or 10 4 cells into the gland free mammary fat pads of three-week-old virgin female BALB/c mice. In the initial studies all outgrowths were removed 10 weeks after injection of cells. The outgrowths that resulted were examined at the whole mount and histological level and were classified as having a normal ductal architecture or as having ductal dysplasia or alveolar adenosis. Outgrowths exhibiting ductal dysplasia were further classified as having mild or severe epithelial hyperplasia. The data indicated that treatment of donor animals with either γ-radiation or DMBA could result in an increased incidence of ductal dysplasias over control levels. Further, the incidence of lesions observed in all groups was influenced by the number of cells used to derive the outgrowths in that lesions were more frequent in outgrowths derived from 10 4 rather than 10 5 cells. The findings of these experiments indicate that acquisition of altered growth potential by mammary cells that results in expression of ductal dysplasia occurs soon after carcinogen treatment and that deriving mammary outgrowths from dissociated cells results in enhanced expression of these lesions

  7. Does Skeletal Muscle Mass Influence Breast Cancer? Evaluating Mammary Tumorigenesis and Progression Genetically Hyper-Muscular Mice

    Science.gov (United States)

    2006-07-01

    the skeletal muscle-specific muscle growth inhibitor myostatin and mice expressing a dominant negative form of the myostatin receptor, Activin...and rates of breast cancer initiation and progression. 15. SUBJECT TERMS Breast cancer, skeletal muscle, myostatin , MPA, DMBA, Activin receptor 16...including interleukins, Insulin-like Growth Factor (IGF) isoforms, IGF-binding proteins and myostatin . To determine the effect of skeletal muscle mass

  8. Chemopreventive effect of Annona muricata on DMBA-induced cell ...

    African Journals Online (AJOL)

    J.B. Minari

    2014-05-24

    May 24, 2014 ... Abstract Background: Breast cancer is the most common type of cancer and leading cause of can- cer death in ... vical cancer, skin cancer, leukemia, lung cancer, prostate can- cer, and so on ..... Androgen receptor activity is.

  9. Chemopreventive effect of Annona muricata on DMBA-induced cell ...

    African Journals Online (AJOL)

    Background: Breast cancer is the most common type of cancer and leading cause of cancer death in women. Breast cancer and cancer related diseases have been treated using surgery, chemotherapy, and radiation therapy, or a combination of these. Despite these therapeutic options, cancer remains associated with high ...

  10. Taurine Attenuates Dimethylbenz[a]anthracene-induced Breast Tumorigenesis in Rats: A Plasma Metabolomic Study.

    Science.gov (United States)

    He, Y U; Li, Qingdi Quentin; Guo, Song Chao

    2016-02-01

    Breast cancer is the most common malignancy and the leading cause of cancer-related mortality in women worldwide. Taurine, the most abundant free amino acid, plays a role in several biological processes in humans and has been shown to have activity against breast cancer and other tumors. To investigate the role and mechanism of taurine action in breast cancer, we used dimethylbenz[a]anthracene (DMBA)-induced breast carcinogenesis in rats as a model of breast cancer. The administration of taurine significantly reduced the DMBA-induced breast cancer rate from 80% to 40% in rats (ptaurine-administered rats. Bioinformatic analysis further revealed that these metabolites are involved in multiple metabolic pathways, including energy, glucose, amino acid, and nucleic acid metabolism, suggesting that the antitumor activity of taurine in rats is mediated through altered metabolism of breast cancer cells. We propose that these differential metabolites may be potential biomarkers for monitoring cancer therapy and prognosis in the clinic. This study provides a scientific basis for further investigations of the antitumor mechanism of taurine and the development of novel therapeutic strategies to treat breast cancer. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  11. Anti-progestins suppress the growth of established tumors induced by 7,12-dimethylbenz(a)anthracene: comparison between RU486 and a new 21-substituted-19-nor-progestin.

    Science.gov (United States)

    Wiehle, Ronald D; Christov, Konstantin; Mehta, Rajendra

    2007-07-01

    In this report, we evaluate the effects of a 21-substituted-19-nor-progestin, CDB-4124, on 7,12,-dimethylbenz(a)anthracene (DMBA)-induced mammary carcinogenesis in rats in comparison with RU486. Sprague-Dawley female rats were treated with DMBA at 50 days of age in order to induce mammary tumors. When the tumors reached the size of 10-12 mm, the animals were treated for 28 days with the vehicle, RU486, progesterone, CDB-4124 at various doses, or CDB-4124 plus progesterone. Anti-progestins resulted in the regression in the size of the existing tumors, and in the suppressed development of new tumors and tumor multiplicity. Progesterone treatment, however, increased the size and multiplicity. Progesterone rendered an increased number of growing tumors as compared to the regression in the anti-progesterone treatment groups. The combination of CDB-4124 and high doses of progesterone opposed the efficacy of CDB-4124. The growth inhibitory effects of the anti-progestins were correlated with increased apoptosis and reduced cell proliferation. These results indicate that anti-progestins should be developed for the chemoprevention and treatment of hormone-responsive breast cancer.

  12. Characterization of chemically induced ovarian carcinomas in an ethanol-preferring rat model: influence of long-term melatonin treatment.

    Directory of Open Access Journals (Sweden)

    Luiz Gustavo A Chuffa

    Full Text Available Ovarian cancer is the fourth most common cause of cancer deaths among women, and chronic alcoholism may exert co-carcinogenic effects. Because melatonin (mel has oncostatic properties, we aimed to investigate and characterize the chemical induction of ovarian tumors in a model of ethanol-preferring rats and to verify the influence of mel treatment on the overall features of these tumors. After rats were selected to receive ethanol (EtOH, they were surgically injected with 100 µg of 7,12-dimethyl-benz[a]anthracene (DMBA plus sesame oil directly under the left ovarian bursa. At 260 days old, half of the animals received i.p. injections of 200 µg mel/100 g b.w. for 60 days. Four experimental groups were established: Group C, rats bearing ovarian carcinomas (OC; Group C+EtOH, rats voluntarily consuming 10% (v/v EtOH and bearing OC; Group C+M, rats bearing OC and receiving mel; and Group C+EtOH+M, rats with OC consuming EtOH and receiving mel. Estrous cycle and nutritional parameters were evaluated, and anatomopathological analyses of the ovarian tumors were conducted. The incidence of ovarian tumors was higher in EtOH drinking animals 120 days post-DMBA administration, and mel efficiently reduced the prevalence of some aggressive tumors. Although mel promoted high EtOH consumption, it was effective in synchronizing the estrous cycle and reducing ovarian tumor mass by 20%. While rats in the C group displayed cysts containing serous fluid, C+EtOH rats showed solid tumor masses. After mel treatment, the ovaries of these rats presented as soft and mobile tissues. EtOH consumption increased the incidence of serous papillary carcinomas and sarcomas but not clear cell carcinomas. In contrast, mel reduced the incidence of sarcomas, endometrioid carcinomas and cystic teratomas. Combination of DMBA with EtOH intake potentiated the incidence of OC with malignant histologic subtypes. We concluded that mel reduces ovarian masses and the incidence of

  13. Ovarian expressed microsomal epoxide hydrolase: Role in detoxification of 4-vinylcyclohexene diepoxide and regulation by phosphatidylinositol-3 kinase signaling

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Poulomi, E-mail: poulomib@iastate.edu [Department of Animal Science, Iowa State University, Ames, IA 50011 (United States); Sen, Nivedita, E-mail: nsen@email.arizona.edu [Department of Physiology, University of Arizona, Tucson, AZ 85724 (United States); Hoyer, Patricia B., E-mail: Hoyer@u.arizona.edu [Department of Physiology, University of Arizona, Tucson, AZ 85724 (United States); Keating, Aileen F., E-mail: akeating@iastate.edu [Department of Animal Science, Iowa State University, Ames, IA 50011 (United States)

    2012-01-01

    4-vinylcyclohexene diepoxide (VCD) is a metabolite of 4-vinylcyclohexene (VCH) which has the potential to be formed in the ovary through CYP2E1 activity. VCD specifically destroys primordial and small primary follicles in the rodent ovary. Mouse ovaries exposed to VCD demonstrate increased mRNA and protein expression of microsomal epoxide hydrolase (mEH), and an inactive tetrol metabolite (4-(1,2-dihydroxy)ethyl-1,2-dihydroxycyclohexane) can be formed in mouse ovarian follicles, potentially through detoxification action of mEH. In contrast, mEH can bioactivate another ovotoxic chemical, 7,12-dimethylbenz[a]anthracene (DMBA) to a more toxic compound, DMBA-3,4-diol-1,2-epoxide. Thus, the present study evaluated a functional role for mEH during detoxification of VCD. Additionally, because inhibition of the phosphatidyinositol-3 kinase (PI3K) signaling pathway in a previous study protected primordial follicles from VCD-induced destruction, but accelerated DMBA-induced ovotoxicity, a role for PI3K in ovarian mEH regulation was evaluated. Using a post-natal day (PND) 4 Fischer 344 rat whole ovary culture system inhibition of mEH using cyclohexene oxide during VCD exposure resulted in a greater (P < 0.05) loss of primordial and small primary follicles relative to VCD-treated ovaries. Also, relative to controls, meh mRNA was increased (P < 0.05) on day 4 of VCD (30 μM) exposure, followed by increased (P < 0.05) mEH protein after 6 days. Furthermore, inhibition of PI3K signaling increased mEH mRNA and protein expression. Thus, these results support a functional role for mEH in the rat ovary, and demonstrate the involvement of PI3K signaling in regulation of ovarian xenobiotic metabolism by mEH. -- Highlights: ► Ovarian mEH functions to metabolize VCD to a less toxic compound. ► mEH expression is increased in a temporal pattern in response to VCD exposure. ► PI3K signaling is involved in regulation of ovarian mEH expression.

  14. Expression of SRSF3 is Correlated with Carcinogenesis and Progression of Oral Squamous Cell Carcinoma.

    Science.gov (United States)

    Peiqi, Liu; Zhaozhong, Guo; Yaotian, Yin; Jun, Jia; Jihua, Guo; Rong, Jia

    2016-01-01

    Oral squamous cell carcinoma (OSCC) is the most common malignancy of head and neck with high mortality rates. The mechanisms of initiation and development of OSCC remain largely unknown. Dysregulated alternative splicing of pre-mRNA has been associated with OSCC. Splicing factor SRSF3 is a proto-oncogene and overexpressed in multiple cancers. The aim of this study was to uncover the relationship between SRSF3 and carcinogenesis and progression of oral squamous cell carcinoma. The expression of SRSF3 in oral normal, dysplasia, or carcinoma tissues was analyzed by immunohistochemistry. The expression levels of EMT-related genes were quantified by real-time quantitative RT-PCR. The expression of SRSF3 in DMBA treated primary cultured oral epithelial cells were analyzed by western blot. SRSF3 is overexpressed in oral cancer and moderate or severe dysplasia tissues. Patients with high grade cancer or lymphatic metastasis showed up-regulated expression of SRSF3. Knockdown of SRSF3 repressed the expression of Snail and N-cadherin in vitro. Carcinogen DMBA treated primary cultured oral epithelial cells showed significantly increased SRSF3 level than in control cells. Our results suggested that SRSF3 is associated with the initiation and development of OSCC and may be a biomarker and therapeutic target of OSCC.

  15. Oral carcinogenesis is not achieved in different carcinogen-treated PAI-1 transgenic and wild-type mouse models.

    Science.gov (United States)

    Avgoustidis, Dimitris; Nisyrios, Themistoklis; Nkenke, Emeka; Lijnen, Roger; Ragos, Vassilis; Perrea, Despina; Donta, Ismini; Vaena, Apostolia; Yapijakis, Christos; Vairaktaris, Eleftherios

    2012-01-01

    In an effort to assess the role of plasminogen activator inhibitor-1 (PAI-1) in oral squamous cancer development and progression, two different carcinogen treatment protocols were conducted. Protocol I included mice from a PAI-1 transgenic (Tg) breed (n=56) and their wild-type (WT) counterparts (n=56), divided into one control group and two main experimental groups, treated with 7,12-dimethylbenz[a]anthracene (DMBA) for 8 and 16 weeks, respectively. Protocol II included the same number and types of animals and groups, which were similarly treated with 4-Nitroquinoline 1-oxide (4-NQO) in drinking water. Two drugs that affect plasma PAI-1 levels, enalapril and pravastatin, were administered to certain subgroups of animals in both protocols. None of the animals developed macroscopically-visible oral cancer lesions. Eleven animals under Protocol I and 52 animals under Protocol II died. Skin lesions were noted only in DMBA-treated animals (n=9). Almost all animals administered with 4-NQO developed alopecia and lost weight, while two of them developed stomach tumours, and one female mouse developed a large ovarian cyst. Transgenic mice may respond differently when used in well-established carcinogen models and oral carcinogenesis is hard to achieve in these rodents.

  16. The Role and Regulation of TNF-Alpha in Normal Rat Mammary Gland During Development and in Breast Cancer.

    Science.gov (United States)

    1996-07-01

    autocrine synthesis of TNFcx by the MEC as well. Normally, there is strict control of the expression of this cytokine; however, it is possible that any...1,2-benz-anthracene (DMBA) (Sigma, St. Louis, MO) (in corn oil) p.o. using standard protocols (30) or via i.p. injection of 1-methyl-l- nitrosourea ...Beutler, B. Dexamethasone and pentoxifylline inhibit endotoxin- induced cachectin/tumor necrosis factor synthesis at separate points in the signalling

  17. Efecto quimioprotector de Bidens pilosa en el cáncer de mama inducido en ratas

    Directory of Open Access Journals (Sweden)

    Jorge Arroyo

    2010-07-01

    Full Text Available Introducción: Bidens pilosa L es una planta perteneciente a la familia Asteraceae, conocida en Perú como amor seco y cadillo. Se le atribuye efectos antiinflamatorio, diurético y hepatoprotector. Objetivos: Determinar el efecto quimioprotector de los compuestos fenólicos y flavonoides extraídos de la planta entera de Bidens pilosa sobre el cáncer de mama inducido en ratas con 7,12-dimetilbenz antraceno (DMBA. Protección medida en base a detención del desarrollo de adenocarcinoma y disminución de marcadores de estrés oxidativo. Diseño: Experimental. Institución: Laboratorio de Farmacología, Facultad de Medicina, Universidad Nacional Mayor de San Marcos. Material biológico: Planta entera de Bidens pilosa L recolectada en La Libertad, Perú, y ratas hembras Holtzmann. Intervenciones: Se obtuvo los compuestos fenólicos y flavonoides por cromatografía en columna rápida, con solventes de polaridad creciente. Mediante cromatografía en capa fina y reactivos de desplazamiento, se aisló cuatro compuestos fenólicos. Los tumores de mama fueron inducidos con DMBA administrado oralmente. Se formó cuatro grupos de seis ratas cada uno: grupo control, grupo con tóxico inductor (TI DMBA del cáncer, grupos con TI más tratamiento de extracto etanólico 300 mg/kg, y grupo con TI más tratamiento de extracto metanólica 300 mg/kg. Principales medidas de resultados: Disminución del desarrollo de adenocarcinoma mamario. Resultados: Se logró disminución significativa del desarrollo de adenocarcinoma mamario con los tratamientos de extracto metanólico y etanólico, siendo mejor con la fracción metanólica; el marcador de estrés oxidativo disminuyó en los grupos que recibieron tratamiento con la planta, siendo significativo con la fracción metanólica; hubo menor número de micronúcleos (genotoxicidad en los animales que recibieron tratamiento. Conclusiones: En condiciones experimentales, el extracto y fracción metanólica de Bidens

  18. [Circadian rhythm variation of the clock genes Per1 and cell cycle related genes in different stages of carcinogenesis of buccal mucosa in animal model].

    Science.gov (United States)

    Tan, Xuemei; Ye, Hua; Yang, Kai; Chen, Dan; Tang, Hong

    2015-07-01

    To investigate the expression and circadian rhythm variation of biological clock gene Per1 and cell cycle genes p53, CyclinD1, cyclin-dependent kinases (CDK1), CyclinB1 in different stages of carcinogenesis in buccal mucosa and its relationship with the development of buccal mucosa carcinoma. Ninety golden hamsters were housed under 12 hours light-12 hours dark cycles, and the model of buccal squamous cell carcinoma was established by using the dimethylbenzanthracene (DMBA) to smear the golden hamster buccal mucosa. Before the DMBA was used and after DMBA was used 6 weeks and 14 weeks respectively, the golden hamsters were sacrificed at 6 different time points (5 rats per time point) within 24 hour, including 4, 8, 12, 16, 20 and 24 hour after lights onset (HALO), and the normal buccal mucosa, precancerous lesions and cancer tissue were obtained, respectively. HE stained sections were prepared to observe the canceration of each tissue. Real time RT-PCR was used to detect the mRNA expression of Per1, p53, CyclinD1, CDK1 and CyclinB1, and a cosine analysis method was applied to determine the circadian rhythm variation of Per1, p53, CyclinD1, CDK1 and CyclinB1 mRNA expression, which were characterized by median, amplitude and acrophase. The expression of Per1, p53, CDK1 and CyclinD1 mRNA in 6 different time points within 24 hours in the tissues of three different stages of carcinogenesis had circadian rhythm, respectively. However, the CyclinB1 mRNA was expressed with circadian rhythm just in normal and cancer tissue (P circadian rhythm was in disorder (P > 0.05). As the development of carcinoma, the median of Per1 and p53 mRNA expression were significantly decreased (P circadian rhythm of clock gene Per1 and cell cycle genes p53, CyclinD1, CDK1, CyclinB1 expression remarkably varied with the occurrence and development of carcinoma. Further research into the interaction between circadian and cell cycle of two cycle activity and relationship with the carcinogenesis may

  19. Influence of caffeine consumption on 7,12-dimethylbenz(a)anthracene-induced mammary gland tumorigenesis in female rats fed a chemically defined diet containing standard and high levels of unsaturated fat.

    Science.gov (United States)

    Welsch, C W; DeHoog, J V

    1988-04-15

    The effect of caffeine (430-500 mg/liter of drinking water) on the initiation and promotion phases of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary gland tumorigenesis in female Sprague-Dawley rats fed a chemically defined diet containing standard (5%) or high (20%) levels of fat (corn oil) was examined. In the initiation studies, caffeine and the standard or high fat diet treatments were provided for 34 days, from 24-29 days of age to 58-63 days of age. Three days prior to termination of caffeine-fat diet treatments, each rat received a single dose of DMBA. In the promotion studies, caffeine and the standard or high fat diets were provided commencing 3 days after a single dose of DMBA (at 56-61 days of age) and until termination of the study. Caffeine consumption, during the initiation phase significantly (P less than 0.05) reduced mammary carcinoma multiplicity (number of tumors/rat), in rats fed either a standard or high fat diet. In the promotion studies, prolonged consumption of caffeine in rats fed either a standard or high fat diet did not significantly effect mammary carcinoma multiplicity. In the early stages of promotion, an apparent increase in mammary carcinoma multiplicity was observed; this increase in mammary carcinoma multiplicity did not, however, reach the 5% level of statistical probability. When caffeine was administered during both the initiation and promotion phases, no significant effect on mammary carcinoma multiplicity was observed. Treatment of rats during the initiation or promotion phases with caffeinated coffee (via drinking water) mimicked the mammary tumor modulating activities of caffeine. Decaffeinated coffee consumption did not effect either the initiation or promotion phases of this tumorigenic process. In both the initiation and promotion studies, caffeine and/or coffee consumption did not significantly affect the incidence of mammary carcinomas (percentage of rats bearing mammary carcinomas) or the mean latency period of

  20. Synthesis of PLGA nanoparticles of tea polyphenols and their strong in vivo protective effect against chemically induced DNA damage

    Directory of Open Access Journals (Sweden)

    Srivastava AK

    2013-04-01

    Full Text Available Amit Kumar Srivastava,1 Priyanka Bhatnagar,2 Madhulika Singh,1 Sanjay Mishra,1 Pradeep Kumar,2 Yogeshwer Shukla,1 Kailash Chand Gupta1,2 1Proteomics Laboratory, Indian Institute of Toxicology Research (CSIR, Lucknow, India; 2Nucleic Acid Research Laboratory, Institute of Genomics and Integrative Biology (CSIR, Delhi University Campus, India Abstract: In spite of proficient results of several phytochemicals in preclinical settings, the conversion rate from bench to bedside is not very encouraging. Many reasons are attributed to this limited success, including inefficient systemic delivery and bioavailability under in vivo conditions. To achieve improved efficacy, polyphenolic constituents of black (theaflavin [TF] and green (epigallocatechin-3-gallate [EGCG] tea in poly(lactide-co-glycolide nanoparticles (PLGA-NPs were entrapped with entrapment efficacy of ~18% and 26%, respectively. Further, their preventive potential against 7,12-dimethylbenzanthracene (DMBA-induced DNA damage in mouse skin using DNA alkaline unwinding assay was evaluated. Pretreatment (topically of mouse skin with either TF or EGCG (100 µg/mouse doses exhibits protection of 45.34% and 28.32%, respectively, against DMBA-induced DNA damage. However, pretreatment with TF-loaded PLGA-NPs protects against DNA damage 64.41% by 1/20th dose of bulk, 71.79% by 1/10th dose of bulk, and 72.46% by 1/5th dose of bulk. Similarly, 51.28% (1/20th of bulk, 57.63% (1/10th of bulk, and 63.14% (1/5th of bulk prevention was noted using EGCG-loaded PLGA-NP doses. These results showed that tea polyphenol-loaded PLGA-NPs have ~30-fold dose-advantage than bulk TF or EGCG doses. Additionally, TF- or EGCG-loaded PLGA-NPs showed significant potential for induction of DNA repair genes (XRCC1, XRCC3, and ERCC3 and suppression of DNA damage responsive genes (p53, p21, MDM2, GADD45α, and COX-2 as compared with respective bulk TF or EGCG doses. Taken together, TF- or EGCG-loaded PLGA-NPs showed a superior

  1. Correlation of regional disease and in vivo PO2 in rat mammary adenocarcinoma.

    OpenAIRE

    Cole, M. A.; Crawford, D. W.; Warner, N. E.; Puffer, H. W.

    1983-01-01

    A knowledge of the distribution of oxygen tension (PO2) and vascularization in neoplasia has been fundamental to understanding relationships between tumor growth, hypoxia, and therapy. We have combined recessed oxygen microcathode and freeze-substitution techniques to correlate in situ PO2 profiles and morphologic features in 7,12-dimethylbenz(a)anthracene (DMBA) tumors in rats. Overlying connective tissue of transplanted tumor was exposed by a 1-2 mm incision and a cross-stitch pattern demar...

  2. Ficus umbellata Vahl. (Moraceae Stem Bark Extracts Exert Antitumor Activities In Vitro and In Vivo

    Directory of Open Access Journals (Sweden)

    Kevine Kamga Silihe

    2017-05-01

    Full Text Available A Ficus umbellata is used to treat cancer. The present work was therefore designed to assess antitumor potentials of F. umbellata extracts in nine different cell lines. Cell cycle, apoptosis, cell migration/invasion, levels of reactive oxygen species (ROS, mitochondrial membrane potential (MMP, caspases activities as well as Bcl-2 and Bcl-xL protein content were assessed in MDA-MB-231 cells. The 7,12-dimethylbenz(aanthracene (DMBA-induced carcinogenesis in rats were also used to investigate antitumor potential of F. umbellata extracts. The F. umbellata methanol extract exhibited a CC50 of 180 μg/mL in MDA-MB-231 cells after 24 h. It induced apoptosis in MCF-7 and MDA-MB-231 cells, while it did not alter their cell cycle phases. Further, it induced a decrease in MMP, an increase in ROS levels and caspases activities as well as a downregulation in Bcl-2 and Bcl-xL protein contents in MDA-MB-231 cells. In vivo, F. umbellata aqueous (200 mg/kg and methanol (50 mg/kg extracts significantly (p < 0.001 reduced ovarian tumor incidence (10%, total tumor burden (58% and 46%, respectively, average tumor weight (57.8% and 45.6%, respectively as compared to DMBA control group. These results suggest antitumor potential of F. umbellata constituents possibly due to apoptosis induction mediated through ROS-dependent mitochondrial pathway.

  3. The biochemical effects of nano tamoxifen and some bioactive components in experimental breast cancer.

    Science.gov (United States)

    Ezzat, Afaf; Abdelhamid, Abdou Osman; El Awady, Mostafa K; Abd El Azeem, Amal S; Mohammed, Dina Mostafa

    2017-11-01

    The effect of nano tamoxifen and some bioactive components such as yeast, isoflavone, and silymarin on the level of resistance and prevention of breast cancer progression in experimental animals is the target of this study. Thirty female Sprague-Dawley rats received a single medication dosage of 7,12-dimethylbenz[a]anthracene (DMBA) intragastrically. After fourteen days of DMBA admission, the procedure protocol started out. Finally, all the experimental results evaluated, tabulated and statistically analyzed. The results demonstrated a highly significant elevation in the 8-OHdG level in group 1 (nano yeast) and 3 (nano silymarin) while the results demonstrated a highly significant reduction in group 2 (nano tamoxifen). The apoptosis results demonstrated a significant elevation in group 3 (nano silymarin) where appeared significant reduction in group 4 (nano isoflavone). ErbB-2 results demonstrated a significant elevation in group 2 (nano tamoxifen) and a significant reduction in each of group 3 (nano silymarin) and 4 (nano isoflavone). The lipid peroxide level demonstrated an extremely significant reduction in group 4 (nano isoflavone). And a significant reduction of total antioxidant was observed in group 3 (nano silymarin) in comparison to injected animals control. This may be considered a new vision and strategy to resist breast cancer disease or prevent progression. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  4. KLF10, transforming growth factor-{beta}-inducible early gene 1, acts as a tumor suppressor

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ki-Duk [Center for Agricultural Biomaterials, Seoul National University, Seoul 151-921 (Korea, Republic of); Laboratory of Protein Engineering and Comparative Immunology, School of Agricultural Biotechnology, Seoul National University, Seoul 151-921 (Korea, Republic of); Kim, Duk-Jung [The Institute of Hankook Life Science, 7-9 Myungryun-dong, Jongno-gu, Seoul 110-521 (Korea, Republic of); Lee, Jong Eun [Department of Anatomy, College of Medicine, Yonsei University, Seoul 120-752 (Korea, Republic of); Yun, Cheol-Heui [Center for Agricultural Biomaterials, Seoul National University, Seoul 151-921 (Korea, Republic of); Laboratory of Protein Engineering and Comparative Immunology, School of Agricultural Biotechnology, Seoul National University, Seoul 151-921 (Korea, Republic of); Lee, Woon Kyu, E-mail: wklee@inha.ac.kr [Laboratory of Developmental Genetics, School of Medicine, Inha University, Incheon 400-712 (Korea, Republic of); Brain Korea 21 Center for Advanced Medical Education, School of Medicine, Inha University, Incheon 400-712 (Korea, Republic of)

    2012-03-09

    Highlights: Black-Right-Pointing-Pointer KLF10{sup -/-} mice exhibited accelerated papilloma development after DMBA/TPA treatment. Black-Right-Pointing-Pointer KLF10{sup -/-} keratinocytes showed increased proliferation and apoptosis. Black-Right-Pointing-Pointer KLF10{sup -/-} MEFs yielded more colonies than wild-type one with H-Ras transfection. Black-Right-Pointing-Pointer KLF10 dose-dependently activated p21{sup WAF1/CIP1} transcription. Black-Right-Pointing-Pointer KLF10 is a tumor suppressor and that it targets p21{sup WAF1/CIP1} transcription. -- Abstract: Krueppel-like factor 10 (KLF10) has been suggested to be a putative tumor suppressor. In the present study, we generated KLF10 deficient mice to explore this hypothesis in vivo. KLF10 deficient mice exhibited increased predisposition to skin tumorigenesis and markedly accelerated papilloma development after DMBA/TPA treatment. On the other hand, KLF10 deficient keratinocytes showed increased proliferation and apoptosis. In colony formation assays after oncogenic H-Ras transfection, KLF10 deficient mouse embryonic fibroblasts (MEFs) yielded more colonies than wild-type MEFs. Furthermore, KLF10 dose-dependently activated p21{sup WAF1/CIP1} transcription, which was independent of p53 and Sp1 binding sites in p21{sup WAF1/CIP1} promoter. This study demonstrates that KLF10 is a tumor suppressor and that it targets p21{sup WAF1/CIP1} transcription.

  5. Disturbance of Mammary UDP-Glucuronosyltransferase Represses Estrogen Metabolism and Exacerbates Experimental Breast Cancer.

    Science.gov (United States)

    Zhou, Xueyan; Zheng, Ziqiang; Xu, Chang; Wang, Juan; Min, Mengjun; Zhao, Yun; Wang, Xi; Gong, Yinhan; Yin, Jiale; Guo, Meng; Guo, Dong; Zheng, Junnian; Zhang, Bei; Yin, Xiaoxing

    2017-08-01

    The progression of breast cancer is closely related to the levels of estrogens within the body. UDP-glucuronosyltransferase (UGT) is an important class of phase II metabolizing enzymes, playing a pivotal role in detoxifying steroid hormone. In the present study, we aim at uncovering the potential dysregulation pattern of UGT and its role in estrogen metabolism and in the pathogenesis of breast cancer. Female Sprague-Dawley rats were treated with 100 mg/kg dimethylbenz(a)anthracene (DMBA) to induce breast cancer. Our results showed that the expression and activity of UGT in mammary tissues were downregulated significantly in DMBA rats. Consistent with this, levels of estradiol, 4-hydroxylated estradiol, and 2-hydroxylated estradiol were increased in both mammary tissues and serum, supporting a notable accumulation of toxic estrogen species in the target tissue of breast cancer. In addition, we also observed the decreased cell migration, cell proliferation, and DNA damage in UGT-transfected MCF-7 cells, suggesting a protective role of UGT against estrogen-induced mammary carcinogenesis. Taken together, these results indicated that accumulation of estrogens induced by UGT deficiency is a critical factor to induce the development of breast cancer. UGT contributes to estrogen elimination, and its glucuronidation capacity influences the estrogen signaling pathway and the pathogenesis of breast cancer. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  6. 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.

  7. Caracterización y validación morfológica y molecular de los tumores mamarios experimentales. Modulación por los lípidos de la dieta

    OpenAIRE

    Costa Trachsel, Irmgard

    2014-01-01

    La tesis doctoral incluye 10 publicaciones que forman parte del proyecto "Lípidos de la Dieta y Cáncer de Mama" que desarrolla el "Grup Multidisciplinari per a l'Estudi del Càncer de Mama" (GMECM). Los trabajos han utilizado el modelo experimental de tumores mamarios inducidos en rata con dimetilbenz(α)antraceno (DMBA) y son el resultado de los siguientes objetivos: a) caracterizar y validar morfológicamente este modelo, con un abordaje singular (artículos 1 y 2); b) estudiar el efecto de las...

  8. Label-free vascular imaging in a spontaneous hamster cheek pouch carcinogen model for pre-cancer detection (Conference Presentation)

    Science.gov (United States)

    Hu, Fangyao; Morhard, Robert; Liu, Heather; Murphy, Helen; Farsiu, Sina; Ramanujam, Nimmi

    2016-03-01

    Inducing angiogenesis is one hallmark of cancer. Tumor induced neovasculature is often characterized as leaky, tortuous and chaotic, unlike a highly organized normal vasculature. Additionally, in the course of carcinogenesis, angiogenesis precedes a visible lesion. Tumor cannot grow beyond 1-2 mm in diameter without inducing angiogenesis. Therefore, capturing the event of angiogenesis may aid early detection of pre-cancer -important for better treatment prognoses in regions that lack the resources to manage invasive cancer. In this study, we imaged the neovascularization in vivo in a spontaneous hamster cheek pouch carcinogen model using a, non-invasive, label-free, high resolution, reflected-light spectral darkfield microscope. Hamsters' cheek pouches were painted with 7,12-Dimethylbenz[a]anthracene (DMBA) to induce pre-cancerous to cancerous changes, or mineral oil as control. High resolution spectral darkfield images were obtained over the course of pre-cancer development and in control cheek pouches. The vasculature was segmented with a multi-scale Gabor filter with an 85% accuracy compared with manually traced masks. Highly tortuous vasculature was observed only in the DMBA treated cheek pouches as early as 6 weeks of treatment. In addition, the highly tortuous vessels could be identified before a visible lesion occurred later during the treatment. The vessel patterns as determined by the tortuosity index were significantly different from that of the control cheek pouch. This preliminary study suggests that high-resolution darkfield microscopy is promising tool for pre-cancer and early cancer detection in low resource settings.

  9. In Vitro and in Vivo Anticancer Activity of Pardaxin against Proliferation and Growth of Oral Squamous Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Yifan Han

    2015-12-01

    Full Text Available Pardaxin (H-GFFALIPKIISSPLFKTLLSAVGSALSSSGGQE-OH, a 33-amino-acid polypeptide, is an antimicrobial peptide (AMP isolated from the marine fish species Pardachirus marmoratus. Pardaxin shows antibacterial and antitumor activities. However, pardaxin-induced inhibition of oral cancer and the mechanism of tumor reduction in buccal pouch carcinogenesis after pardaxin painting remain undetermined. Additionally, the toxic effects of pardaxin on normal tissue remain unclear. The present study investigated the anticancer activity of pardaxin in oral squamous cell carcinoma (OSCC cells in the hamster buccal pouch model with or without 7,12-dimethylbenz[a]anthracene (DMBA pretreatment. This is the first study to confirm the effects of pardaxin on normal tissue and its nontoxic effects in vivo. Cell viability assays and colony formation tests in OSCC cell lines (SCC-4 demonstrated that pardaxin reduced cell viability in a dose-dependent manner. Immunofluorescence staining of cleaved caspase-3 in SCC-4 cells revealed that expression of activated caspase-3 in SCC-4 cells significantly increased after 24-h treatment with pardaxin. Additionally, a cell cycle analysis indicated that pardaxin treatment resulted in the cell cycle arrest of SCC-4 cells in the G2/M phase, thereby limiting cell proliferation. Furthermore, pardaxin treatment substantially alleviated carcinogenesis in the DMBA-induced hamster buccal pouch model by lowering prostaglandin E2 levels. These results suggest that pardaxin is a potential marine drug for adjuvant chemotherapy for human OSCC and oral cancer.

  10. Monitoring pancreatic carcinogenesis by the molecular imaging of cathepsin E in vivo using confocal laser endomicroscopy.

    Directory of Open Access Journals (Sweden)

    Hui Li

    Full Text Available The monitoring of pancreatic ductal adenocarcinoma (PDAC in high-risk populations is essential. Cathepsin E (CTSE is specifically and highly expressed in PDAC and pancreatic intraepithelial neoplasias (PanINs, and its expression gradually increases along with disease progression. In this study, we first established an in situ 7,12-dimethyl-1,2-benzanthracene (DMBA-induced rat model for PanINs and PDAC and then confirmed that tumorigenesis properties in this model were consistent with those of human PDAC in that CTSE expression gradually increased with tumor development using histology and immunohistochemistry. Then, using in vivo imaging of heterotopically implanted tumors generated from CTSE- overexpressing cells (PANC-1-CTSE in nude mice and in vitro imaging of PanINs and PDAC in DMBA-induced rats, the specificity of the synthesized CTSE-activatable probe was verified. Quantitative determination identified that the fluorescence signal ratio of pancreatic tumor to normal pancreas gradually increased in association with progressive pathological grades, with the exception of no significant difference between PanIN-II and PanIN-III grades. Finally, we monitored pancreatic carcinogenesis in vivo using confocal laser endomicroscopy (CLE in combination with the CTSE-activatable probe. A prospective double-blind control study was performed to evaluate the accuracy of this method in diagnosing PDAC and PanINs of all grades (>82.7%. This allowed us to establish effective diagnostic criteria for CLE in PDAC and PanINs to facilitate the monitoring of PDAC in high-risk populations.

  11. Efek antigenotoksik ekstrak etanolik daun sirsak (Annona muricata Linn terhadap frekuensi mikronukleus mukosa bukal tikus Sprague Dawley

    Directory of Open Access Journals (Sweden)

    Tyas Prihatiningsih

    2017-10-01

    Full Text Available The effect of soursop leaves (Annona uricata linn ethanolic extract on micronucleus frequency  of buccal mucosa epithelium of Sprague dawley rats. Polycyclic aromatic hydrocarbons is one of the largest  groups of carcinogen in environment. 7,12-Dimetillbez (α antransena is a compound of PAH class that has genotoxic carcinogen potency. One of the most frequently applied genotoxicity tests is micronucleus test. Soursop is a plant that can grow well in Indonesia. Its leaves contain avonoid and acetogenin assumed to have potential chemopreventive and anticancer activities. The aim of this study was to assess the antigenotoxic effect soursop leaves ethanolic extraction the micronucleus frequency of DMBA-induced buccal mucosa of rat. This research was conducted on 24 male Sprague Dawley rats aged 5 weeks and divided into six groups. Carcinogenesis on the lingual dorsum of group I-III were induced by DMBA topically 3 times a week for 16 weeks, group II and III were not only induced by carcinogenesis, but also were given soursop leaves ethanolic extract of 100 and 200 mg/kg body weight for 18 weeks, group IV was given soursop leaves ethanolic extract 200 mg/kg body weight, group V was given DMSO 1% and group VI was given no treatment. After 18th week, buccal mucosa swab for micronucleus test was conducted and stained with Feulgen-Rossenbeck method. The number of micronucleus is calculated under a light microscope, data were analized using using one-way ANOVA followed by Tukey HSD. The result showed that the average of buccal micronucleus frequency of group II (13 ± 0.82 and group III (12 ± 0.96 were decrease signicantly (p<0,05 than group I (24 ± 1.71. From the experiment,   it is concluded that the soursop leaves ethanolic extract has antigenotoxic effect shown by decreasing of the buccal micronucleus frequency of rat. ABSTRAK Polycyclic aromatic hydrocarbon atau PAH merupakan salah satu kelompok karsinogen terbesar di lingkungan. 7

  12. A viral long terminal repeat expressed in CD4+CD8+ precursors is downregulated in mature peripheral CD4-CD8+ or CD4+CD8- T cells.

    OpenAIRE

    Paquette, Y; Doyon, L; Laperrière, A; Hanna, Z; Ball, J; Sekaly, R P; Jolicoeur, P

    1992-01-01

    The long terminal repeat from a thymotropic mouse mammary tumor virus variant, DMBA-LV, was used to drive the expression of two reporter genes, murine c-myc and human CD4, in transgenic mice. Expression was observed specifically in thymic immature cells. Expression of c-myc in these cells induced oligoclonal CD4+ CD8+ T-cell thymomas. Expression of human CD4 was restricted to thymic progenitor CD4- CD8- and CD4+ CD8+ T cells and was shut off in mature CD4+ CD8- and CD4- CD8+ T cells, known to...

  13. Study of new complexes of uranium and comba radical. II-Complexes formed in the presence of OH-, CO3H, CH3-COO-, and B4O7

    International Nuclear Information System (INIS)

    Vera Palomino, V.; Galiano Sedano, J. A.; Parellada Bellod, R.; Bellido Gonzalez, A.

    1975-01-01

    Several complexes extracted with CDMBAC organic solutions from uranium aqueous solutions, in presence of sodium and ammonium hydroxides, are studied. These complexes fit to the general formula: U0 2 (OH) n (C[DMBA) n -2 . The uranium extraction in presence of an excess of sodium bicarbonate is also studied. From aqueous solutions of uranyl acetate we have isolated the complex U0 2 (CH 3 -C00) n (CDMBA) n -2. In presence of boric acid and sodium tetraborate an U-CDMBA compound containing boron in its molecule has being obtained by precipitation and liquid-liquid extraction. (Author) 5 refs

  14. Expression of CYP1C1 and CYP1A in Fundulus heteroclitus during PAH-induced carcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Wang Lu [Pharmacology and Environmental Toxicology, University of Mississippi, University, MS (United States); Camus, Alvin C. [Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA (United States); Dong, Wu; Thornton, Cammi [Pharmacology and Environmental Toxicology, University of Mississippi, University, MS (United States); Willett, Kristine L., E-mail: kwillett@olemiss.edu [Pharmacology and Environmental Toxicology, University of Mississippi, University, MS (United States)

    2010-09-15

    CYP1C1 is a relatively newly identified member of the cytochrome P450 family 1 in teleost fish. However, CYP1C1's expression and physiological roles relative to the more recognized CYP1A in polycyclic aromatic hydrocarbons (PAHs) induced toxicities are unclear. Fundulus heteroclitus fry were exposed at 6-8 days post-hatch (dph) and again at 13-15 dph for 6 h to dimethyl sulfoxide (DMSO) control, 5 mg/L benzo[a]pyrene (BaP), or 5 mg/L dimethylbenzanthracene (DMBA). Fry were euthanized at 0, 6, 18, 24 and 30 h after the second exposure. In these groups, both CYP1A and CYP1C1 protein expression were induced within 6 h after the second exposure. Immunohistochemistry (IHC) results from fry revealed strongest CYP1C1 expression in renal tubular and intestinal epithelial cells. Additional fish were examined for liver lesions 8 months after initial exposure. Gross lesions were observed in 20% of the BaP and 35% of the DMBA-treated fish livers. Histopathologic findings included foci of cellular alteration and neoplasms, including hepatocellular adenoma, hepatocellular carcinoma and cholangioma. Strong CYP1A immunostaining was detected diffusely in altered cell foci and on the invading margin of hepatocelluar carcinomas. Lower CYP1A expression was seen in central regions of the neoplasms. In contrast, CYP1C1 was only detectable and highly expressed in proliferated bile duct epithelial cells. Our CYP1C1 results suggest the potential for tissue specific CYP1C1-mediated PAH metabolism but not a more chronic role in progression to liver hepatocellular carcinoma.

  15. Efficacy of krypton laser photodynamic therapy for oral mucosa dysplasia in 9,10-dimethyl-1,2-benzanthracene-treated hamsters.

    Science.gov (United States)

    Shen, Lingyue; Xu, Qing; Li, Pingping; Zhou, Guoyu

    2013-11-01

    The present study aimed to evaluate the efficacy of krypton laser photodynamic therapy (PDT) with PsD-007 for the treatment of oral mucosa dysplasia in 9,10-dimethyl-1,2-benzanthracene (DMBA)-treated hamsters. A DMBA-induced hamster cheek pouch model of precancerous lesions was created and the resultant 25 hamsters were divided into five groups. The right side was treated with PDT and the left side was used as the positive control. Following systemic anesthesia, an incision was made in the groin area to expose the femoral vein. PsD-007 was administered intravenously through the femoral vein. Various doses of photosensitizer were used to treat groups A-E. Subsequent to closing the incision, the right side of the buccal mucosa was irradiated with light using the krypton laser at a wavelength of 413 nm, a power density of 150 mW/cm 2 and an irradiation time of 20 min. At six weeks post-surgery, the response was analyzed using histological examinations of the buccal pouch mucosa. A total of 24 hamsters completed the six-week observation period, as one hamster from group C died in the second week following the PDT. Of all 24 irradiated sides, 15 formed normal mucosal tissues and nine demonstrated mild dysplasia. Of the total control sides, six developed moderate dysplasia, five developed severe dysplasia and 13 progressed to carcinoma in situ or squamous cell carcinoma (SCC). The results revealed a significant difference between the two sides (P10 mg/kg, there was no statistical difference (P>0.05). PsD-007-mediated krypton laser PDT is effective for the treatment of oral mucosa dysplasia in hamsters.

  16. A study on CYP1A inhibitory action of E-2-(4'-methoxybenzylidene)-1-benzosuberone and some related chalcones and cyclic chalcone analogues

    International Nuclear Information System (INIS)

    Monostory, Katalin; Tamasi, Viola; Vereczkey, Laszlo; Perjesi, Pal

    2003-01-01

    In vivo investigation of E-2-(4'-methoxybenzylidene)-1-benzosuberone (4a) on the 7,12-dimethylbenz[a]anthracene (DMBA)-induced onco/tumor suppressor gene expressions suggested that inhibition of metabolic activation of DMBA might play a role in the observed activity of the compound. In order to explore this possible biological action we have investigated whether 4a and some of its structurally related analogues had inhibitory effects on the CYP1A enzymes. During our study 7-ethoxyresorufin O-dealkylation activity of CYP1A isoenzymes was measured in liver microsomes prepared from 3-methylcholanthrene treated male rats. Inhibition constants (K i values) were determined by using different concentrations of 7-ethoxyresorufin and the investigated chalcones (1), E-2-benzylidene-1-indanones (2), -tetralones (3) and -benzosuberones (4). Each compound was found to be a strong competitive inhibitor of the CYP1A enzymes. Their inhibitory activity was comparable with or even higher than that of 7,8-benzoflavone, the known strong CYP1A inhibitor used as reference substance. By proper selection of the substituents on the benzylidene moiety we investigated how the inhibitory activity (K i value) of 1-4 varied as a function of the ring size (n=0, 5, 6, 7) carbon atoms, and the nature as well as the position of the substituents. To test applicability of the previously set structural requirements for binding of xenobiotics to the CYP1A enzymes we compared some topological, physico-chemical and quantum mechanical parameters of 1-4 with 7-ethoxyresorufin and 7,8-benzoflavone, the investigated CYP1A substrate and inhibitor, respectively

  17. Cell and microsome mediated binding of 7,12-dimethylbenz(a)anthracene to DNA studied by fluorescence spectroscopy.

    Science.gov (United States)

    Ivanovic, V; Geacintov, N E; Jeffrey, A M; Fu, P P; Harvey, R G; Weinstein, I B

    1978-03-01

    Fluorescence spectra of DNA isolated from hamster embryo cells incubated with 7,12-dimethylbenz(a)anthracene, or DNA modified in a microsomal system by reaction with this carcinogen or its 7-hydroxymethyl derivative, were compared to various model compounds. The spectra indicate that the DMBA derivative bound to DNA, in all 3 cases, has a 9,10-dimethylanthracene-like chromophore. They also provide the first evidence of the similarity in structure of the DNA-bound products between 7,12-dimethylbenz(a)anthracene and its 7-hydroxymethyl derivative. Our results are consistent with an activation mechanism that involves saturation of the 1,2,3,4-ring positions.

  18. Chemopreventive and Antiproliferative Effect of Andrographis Paniculata Extract

    Directory of Open Access Journals (Sweden)

    Agrawal RC

    2017-06-01

    Full Text Available An Andrographis paniculata leaf and stem extract was studied in Hela cells lines by In Vitro methods and anti promoting effect by skin tumour model. The dose dependent cytotoxicity was observed in HeLa cell lines by stem and leaves extracts of Andrographis paniculata extract. The prevention of bone marrow micronucleus formation by Andrographis paniculata leaves and stem extract was also observed. The reductions in tumour numbers were observed. The glutathione level was increased in the liver of animals which received the treatment of Andrographis extract along with DMBA + Croton Oil. The revealing information about the anticancer, antiproliferative and antimutagenic effect of an Andrographis paniculata extract was observed.

  19. Investigation of in vivo potential of scorpion venom against skin tumorigenesis in mice via targeting markers associated with cancer development

    Directory of Open Access Journals (Sweden)

    Al Asmari AK

    2016-10-01

    Full Text Available Abdulrahman K Al Asmari, Abdul Quaiyoom Khan Research Centre, Prince Sultan Military Medical City, Riyadh, Saudi Arabia Abstract: Cancer is the leading cause of morbidity and mortality all over the world in spite of the advances made in its management. In this study, we investigated the in vivo antitumorigenic potential of the venom obtained from a medically important scorpion species Leiurus quinquestriatus on chemically induced skin cancer in mice. Animals were divided into five groups, with 13 animals in each group. All the treatments were given topically on the shaved dorsal surface of the skin. Animals in Group 1 received vehicle only (0.2 mL acetone. Moreover, 7,12-dimethylbenz[a]anthracene (DMBA, 400 nmol per mouse was applied to all the animals in the remaining four groups. After 1 week, different concentrations of venom (17.5 µg, 35 µg, and 52.5 µg per animal were applied to each animal in the Groups III–V. Thirty minutes after the application of venom, croton oil was applied on the same position where venom was administered to the animals of Groups III–V. Animals in Group II were treated as the positive control (without venom and received croton oil as in Groups III–V. The findings of this study revealed that venom extract of L. quinquestriatus inhibits DMBA + croton oil-induced mouse skin tumor incidence and tumor multiplicity. Venom treatment also decreased the expression of proinflammatory cytokines. Immunohistochemistry results showed a downregulation of the expression of molecular markers such as Ki-67, nuclear factor kappa-B, cyclooxygenase-2, B-cell lymphoma-2, and vascular endothelial growth factor, in venom-treated animals. Our findings suggest that the venom of L. quinquestriatus possesses in vivo anticancer potential and may be used in the development of anticancer molecules. Keywords: Leiurus quinquestriatus, skin cancer, apoptosis, immunosuppression

  20. A Mouse Model for Human Anal Cancer

    Science.gov (United States)

    Stelzer, Marie K.; Pitot, Henry C.; Liem, Amy; Schweizer, Johannes; Mahoney, Charles; Lambert, Paul F.

    2010-01-01

    Human anal cancers are associated with high-risk human papillomaviruses (HPVs) that cause other anogenital cancers and head and neck cancers. As with other cancers, HPV16 is the most common high-risk HPV in anal cancers. We describe the generation and characterization of a mouse model for human anal cancer. This model makes use of K14E6 and K14E7 transgenic mice in which the HPV16 E6 and E7 genes are directed in their expression to stratified squamous epithelia. HPV16 E6 and E7 possess oncogenic properties including but not limited to their capacity to inactivate the cellular tumor suppressors p53 and pRb, respectively. Both E6 and E7 were found to be functionally expressed in the anal epithelia of K14E6/K14E7 transgenic mice. To assess the susceptibility of these mice to anal cancer, mice were treated topically with dimethylbenz[a]anthracene (DMBA), a chemical carcinogen that is known to induce squamous cell carcinomas in other sites. Nearly 50% of DMBA-treated HPV16 E6/E7 transgenic mice showed overt signs of tumors; whereas, none of the like treated non-transgenic mice showed tumors. Histopathological analyses confirmed that the HPV16 transgenic mice were increased in their susceptibility to anal cancers and precancerous lesions. Biomarker analyses demonstrated that these mouse anal cancers exhibit properties that are similar to those observed in HPV-positive precursors to human anal cancer. This is the first mouse model for investigating the contributions of viral and cellular factors in anal carcinogenesis, and should provide a platform for assessing new therapeutic modalities for treating and/or preventing this type of cancer. PMID:20947489

  1. Cytotoxic effects of some animal and vegetable extracts and some chemicals on liver and colon carcinoma and myosarcoma

    International Nuclear Information System (INIS)

    Bayazit, Vahdettin

    2004-01-01

    To study, the cytotoxic effects of some biological and chemical agents on G, S, G, M and G phases of liver and colon carcinomas and myosarcoma cells obtained with chemical carcinogens dimethylbenzanthracene (Dmba) and cadmium chloride. Eight rabbit livers, colon carcinoma and myosarcoma cell lines were obtained by injection of Dmba in the Biology Laboratory, of the University of Dumlupinar, Kutahya, Turkey between January 2001 and June 2003. All lines were grown at 37degrees celsius and 5% carbon dioxide in sterile RPMI-1640 medium with 10% fetal bovine serum after addition of glutamate, penicillin (50 units/ml) and streptomycin (50 ug/ml) (complete medium). Cells were grown on standard tissue culture plastic flasks to 80% confluence and passed by trypsinization. Tortoise (Testudo graeca) shell, sponge (Geodia cydonium), medusa (Aurelia aurita), meat flies (Calliphora erythrocephala) larva, frog (Rana ridibunda) larva and juniper (Juniperus communis) berry extracts killed a large amount of the liver and colon carcinomas and the myosarcoma cells in G2, M and G0 phases (p<0.01). The mistletoe (Viscum album) extract had more effect in only the G0 phase (p<0.05). Genistein, genistin, glycitein, glycitin, daitzein and daitzin have significantly decreased in the cancer cells tests, particularly, genistein and daitzein caused the apoptotic effect in G2, M and G0 phases (p<0.01). Cesium chloride, a mixture of cesium chloride with magnesium chloride had the most effect on tumor cells (p<0.01). AzhexSi, Azhex-AzhepSi, Et-Azhex-AzhepSi, AzhepSi, Hexamine and DL 54 have been inhibited in various levels of the cancer cells (p<0.05, p<0.01). This data suggest that some biological extracts and chemicals tested may be useful chemotherapeutic agents to inhibit the growth of cancer cells. This study sheds some light for new anti cancerogenic experiments preventing various cancers on humans. (author)

  2. Mutation of Chinese hamster cells by near-UV activation of promutagens

    International Nuclear Information System (INIS)

    Barnhart, B.J.; Cox, S.H.

    1980-01-01

    A tissue-culture assay for mutagenesis and cytotoxicity incorporating near ultraviolet (NUV) light activation of polyaromatic hydrocarbons (PAH) has been developed. Cultures of Chinese hamster cells (line CHO) growing in suspension culture were inoculated with benzo[a]pyrene (B[a]P), 7,12-dimethylbenzanthracene (DMBA) or shale-oil retort-water and exposed to light from a high-pressure mercury lamp fitted with a Corning NUV bandpass filter. This light source both permitted activation of PAH and the shale-oil water and precluded detectable damage to DNA. Neither the PAH nor the NUV alone had any effect on cell survival or mutation frequencies but the chemicals plus NUV were extremely effective in producing mutations to 6-thioguanine resistance (hgprt gene). (orig.)

  3. The Role of Fibroblast Growth Factor Binding Protein 1 in Skin Carcinogenesis and Inflammation

    DEFF Research Database (Denmark)

    Schmidt, Marcel Oliver; Garman, Khalid Ammar; Lee, Yong Gu

    2018-01-01

    , and is upregulated in various cancers. Here we evaluated the contribution of endogenous FGFBP1 to development and homeostasis as well as to skin pathologies utilizing Fgfbp1-knockout (KO) mice. Relative to wild-type (WT) littermates KO mice showed no gross pathologies. Still, in KO mice a significant thickening...... of the epidermis associated with a decreased transepidermal water loss and increased pro-inflammatory gene expression in the skin was detected. Also, skin carcinogen challenge by DMBA/TPA resulted in delayed and reduced papillomatosis in KO mice. This was paralleled by delayed healing of skin wounds and reduced...... angiogenic sprouting in subcutaneous matrigel plugs. Heterozygous GFP-knock-in mice revealed rapid induction of gene expression during papilloma induction and during wound healing. Examination of WT skin grafted onto Fgfbp1 GFP knockin reporter hosts and bone marrow transplants from the GFP reporter model...

  4. Uterine responses to feeding soy protein isolate and treatment with 17β-estradiol differ in ovariectomized female rats

    Energy Technology Data Exchange (ETDEWEB)

    Ronis, Martin J., E-mail: mronis@lsuhsc.edu [Department of Pharmacology & Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, LA 70112 (United States); Gomez-Acevedo, Horacio; Blackburn, Michael L. [Arkansas Children' s Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, AR 72202 (United States); Cleves, Mario A. [Arkansas Children' s Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, AR 72202 (United States); Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, AR 72202 (United States); Singhal, Rohit [Department of Pharmacology & Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR 72202 (United States); Badger, Thomas M. [Arkansas Children' s Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, AR 72202 (United States); Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, AR 72202 (United States)

    2016-04-15

    There are concerns regarding reproductive toxicity from consumption of soy foods, including an increased risk of endometriosis and endometrial cancer, as a result of phytoestrogen consumption. In this study, female rats were fed AIN-93G diets made with casein (CAS) or soy protein isolate (SPI) from postnatal day (PND) 30, ovariectomized on PND 50 and infused with 5 μg/kg/d 17β-estradiol (E2) or vehicle. E2 increased uterine wet weight (P < 0.05). RNAseq analysis revealed that E2 significantly altered expression of 1991 uterine genes (P < 0.05). SPI feeding had no effect on uterine weight and altered expression of far fewer genes than E2 at 152 genes (P < 0.05). Overlap between E2 and SPI genes was limited to 67 genes. Functional annotation analysis indicated significant differences in uterine biological processes affected by E2 and SPI and little evidence for recruitment of estrogen receptor (ER)α to the promoters of ER-responsive genes after SPI feeding. The major E2 up-regulated uterine pathways were carcinogenesis and extracellular matrix organization, whereas SPI feeding up-regulated uterine peroxisome proliferator activated receptor (PPAR) signaling and fatty acid metabolism. The combination of E2 and SPI resulted in significant regulation of 504 fewer genes relative to E2 alone. The ability of E2 to induce uterine proliferation in response to the carcinogen dimethybenz(a)anthracene (DMBA) as measured by expression of PCNA and Ki67 mRNA was suppressed by feeding SPI (P < 0.05). These data suggest that SPI is a selective estrogen receptor modulator (SERM) interacting with a small sub-set of E2-regulated genes and is anti-estrogenic in the presence of endogenous estrogens. - Highlights: • Concerns exist regarding risk of uterine cancer from consumption of soy products. • These concerns are related to potential estrogenicity. • Estradiol and soy protein isolate effects on uterine gene expression were compared. • Soy acts as a selective estrogen

  5. Low-dose synergistic immunosuppression of T-dependent antibody responses by polycyclic aromatic hydrocarbons and arsenic in C57BL/6J murine spleen cells

    International Nuclear Information System (INIS)

    Li Qian; Lauer, Fredine T.; Liu Kejian; Hudson, Laurie G.; Burchiel, Scott W.

    2010-01-01

    Polycyclic aromatic hydrocarbons (PAHs) and arsenic are both environmental agents that are known to have significant immunotoxicity. Previous studies have shown that PAH exposure of spleen cells in vitro produces significant immune suppression of humoral immunity, especially when P450 activation products are examined. Exposure to arsenic, particularly sodium arsenite, has also been found to be suppressive to antibody responses in vitro and in vivo. The purpose of the present studies was to examine the immunotoxicity of PAHs and arsenite following coexposures with the theory being that the agents may exert synergistic actions, which might be based on their different mechanisms of action. Spleen cells were isolated from male C57BL/6J wild-type mice and treated with PAHs and/or arsenic (arsenite or arsenate). Immunotoxicity assays were used to assess the T-dependent antibody response (TDAR) to sheep red blood cells (SRBCs), measured by a direct plaque-forming cell (PFC) assay. Cell viability was measured by trypan blue staining. Spleen cell viability was not altered following 4 days of PAH and/or arsenic treatment. However, the TDAR demonstrated suppression by both PAHs and arsenic in a concentration-dependent manner. p53 was also induced by NaAsO 2 (As 3+ ) and PAHs alone or in combination. The PAHs and their metabolites investigated included benzo[a]pyrene (BaP), BaP-7,8-diol, BaP-7,8-diol-9,10-epoxide (BPDE), 7,12-dimethylbenz[a]anthracene (DMBA), DMBA-3,4-diol, dibenzo[a,l]pyrene (DB[a,l]P). PAH metabolites were found to be more potent than parent compounds in producing immunosuppression and inducing p53 expression. Interestingly, DB[a,l]P, a potent carcinogenic PAH not previously characterized for immunotoxicity, was also found to be strongly immunosuppressive. Arsenite (NaAsO 2 , As 3+ ) was found to produce immunosuppression at concentrations as low as 0.5 μM and was immunosuppressive at a 10-fold lower concentration than sodium arsenate (Na 2 HAsO 4 , As 5

  6. Ionizing radiation in tumor promotion and progression

    International Nuclear Information System (INIS)

    Mitchel, R.E.J.

    1990-08-01

    Chronic exposure to beta radiation has been tested as a tumor promoting or progressing agent. The dorsal skins of groups of 25 female SENCAR mice were chemically initiated with a single exposure to DMBA, and chronic exposure to strontium-90/yttrium-90 beta radiation was tested as a stage 1, stage 2 or complete skin tumor promoter. Exposure of initiated mice to 0.5 gray twice a week for 13 weeks produced no papillomas, indicating no action as a complete promoter. Another similar group of animals was chemically promoted through stage 1 (with TPA) followed by 0.5 gray of beta radiation twice a week for 13 weeks. Again no papillomas developed indicating no action of chronic radiation as a stage 2 tumor promoter. The same radiation exposure protocol in another DMBA initiated group receiving both stage 1 and 2 chemical promotion resulted in a decrease in papilloma frequency, compared to the control group receiving no beta irradiation, indicating a tumor preventing effect of radiation at stage 2 promotion, probably by killing initiated cells. Chronic beta radiation was tested three different ways as a stage 1 tumor promoter. When compared to the appropriate control, beta radiation given after initiation as a stage 1 promoter (0.5 gray twice a week for 13 weeks), after initiation and along with a known stage 1 chemical promoter (1.0 gray twice a week for 2 weeks), or prior to initiation as a stage 1 promoter (0.5 gray twice a week for 4 weeks), each time showed a weak (∼ 15% stimulation) but statistically significant (p<0.01) ability to act as a stage 1 promoter. When tested as a tumor progressing agent delivered to pre-existing papillomas, beta radiation (0.5 gray twice a week for 13 weeks) increased carcinoma frequency from 0.52 to 0.68 carcinoma/animal, but this increase was not statistically significant at the 95% confidence level. We conclude that in the addition to the known initiating, progressing and complete carcinogenic action of acute exposures to ionizing

  7. Uterine responses to feeding soy protein isolate and treatment with 17β-estradiol differ in ovariectomized female rats

    International Nuclear Information System (INIS)

    Ronis, Martin J.; Gomez-Acevedo, Horacio; Blackburn, Michael L.; Cleves, Mario A.; Singhal, Rohit; Badger, Thomas M.

    2016-01-01

    There are concerns regarding reproductive toxicity from consumption of soy foods, including an increased risk of endometriosis and endometrial cancer, as a result of phytoestrogen consumption. In this study, female rats were fed AIN-93G diets made with casein (CAS) or soy protein isolate (SPI) from postnatal day (PND) 30, ovariectomized on PND 50 and infused with 5 μg/kg/d 17β-estradiol (E2) or vehicle. E2 increased uterine wet weight (P < 0.05). RNAseq analysis revealed that E2 significantly altered expression of 1991 uterine genes (P < 0.05). SPI feeding had no effect on uterine weight and altered expression of far fewer genes than E2 at 152 genes (P < 0.05). Overlap between E2 and SPI genes was limited to 67 genes. Functional annotation analysis indicated significant differences in uterine biological processes affected by E2 and SPI and little evidence for recruitment of estrogen receptor (ER)α to the promoters of ER-responsive genes after SPI feeding. The major E2 up-regulated uterine pathways were carcinogenesis and extracellular matrix organization, whereas SPI feeding up-regulated uterine peroxisome proliferator activated receptor (PPAR) signaling and fatty acid metabolism. The combination of E2 and SPI resulted in significant regulation of 504 fewer genes relative to E2 alone. The ability of E2 to induce uterine proliferation in response to the carcinogen dimethybenz(a)anthracene (DMBA) as measured by expression of PCNA and Ki67 mRNA was suppressed by feeding SPI (P < 0.05). These data suggest that SPI is a selective estrogen receptor modulator (SERM) interacting with a small sub-set of E2-regulated genes and is anti-estrogenic in the presence of endogenous estrogens. - Highlights: • Concerns exist regarding risk of uterine cancer from consumption of soy products. • These concerns are related to potential estrogenicity. • Estradiol and soy protein isolate effects on uterine gene expression were compared. • Soy acts as a selective estrogen

  8. DNA repair in human cells exposed to combinations of carcinogenic agents

    International Nuclear Information System (INIS)

    Setlow, R.B.; Ahmed, F.E.

    1980-01-01

    Normal human and XP 2 fibroblasts were treated with uv plus uv-mimetic chemicals. The uv dose used was sufficient to saturate the uv excision repair system. Excision repair after combined treatments was estimated by unscheduled DNA synthesis, BrdUrd photolysis, and the loss of sites sensitive to a uv specific endonuclease. Since the repair of damage from uv and its mimetics is coordinately controlled we expected that there would be similar rate-limiting steps in the repair of uv and chemical damage and that after a combined treatment the total amount of repair would be the same as from uv or the chemicals separately. The expectation was not fulfilled. In normal cells repair after a combined treatment was additive whereas in XP cells repair after a combined treatment was usually less than after either agent separately. The chemicals tested were AAAF, DMBA-epoxide, 4NQO, and ICR-170

  9. Estrogen receptor binding radiopharmaceuticals: II. Tissue distribution of 17 α-methylestradiol in normal and tumor-bearing rats

    International Nuclear Information System (INIS)

    Feenstra, A.; Vaalburg, W.; Nolten, G.M.J.; Reiffers, S.; Talma, A.G.; Wiegman, T.; van der Molen, H.D.; Woldring, M.G.

    1983-01-01

    Tritiated 17α-methylestradiol was synthesized to investigate the potential of the carbon-11-labeled analog as an estrogen-receptor-binding radiopharmaceutical. In vitro, 17α-methylestradiol is bound with high affinity to the cytoplasmic estrogen receptor from rabbit uterus (K/sub d/ = 1.96 x 10 -10 M), and it sediments as an 8S hormone-receptor complex in sucrose gradients. The compound shows specific uptake in the uterus of the adult rat, within 1 h after injection. In female rats bearing DMBA-induced tumors, specific uterine and tumor uptakes were observed, although at 30 min the tumor uptake was only 23 to 30% of the uptake in the uterus. Tritiated 17α-methylestradiol with a specific activity of 6 Ci/mmole showed a similar tissue distribution. Our results indicate that a 17 α-methylestradiol is promising as an estrogen-receptor-binding radiopharmaceutical

  10. Mammary carcinogenesis induced by three consecutive 14 MeV neutron irradiations in Sprague-Dawley rats

    International Nuclear Information System (INIS)

    Jacrot, M.; Mouriquand, J.; Mouriquand, C.

    1978-01-01

    At high doses (400 to 800 rads) the relative biological effectiveness (R.B.E.) of neutrons is two or three times greater than that of X-rays or gamma radiation. The neutron irradiation-induced mammary carcinogenesis threshold, if any, is certainly very low in Sprague-Dawley females. The purpose of this work is to test the possibilities offered by three consecutive 14 MeV neutron irradiations in the mammary carcinogenesis region of Sprague-Dawley rats. The results of these experiments show a hormone-dependence of tumour promotion similar to that observed with chemical carcinogenetic agents. However these tumours, by their recurrences and possible metastases, bear some resemblance to breast cancers in women. Although the tumour induction frequencies seem modest in relation to those obtained with the DMBA model they should nevertheless prove very useful in the study of hormone effects liable to control the appearance of such radioinduced cancers [fr

  11. Effects of maternal exposure to cow´s milk high or low in isoflavones on carcinogen-induced mammary tumorigenesis among rat offspring

    DEFF Research Database (Denmark)

    Nielsen, Tina Skau; Purup, Stig; Warri, A

    2011-01-01

    We investigated whether maternal exposure during pregnancy to cow's milk containing endogenous estrogens and insulin like growth factor 1 (IGF-1) and either high or low levels of isoflavones from dietary legumes (HIM and LIM, respectively) affected carcinogen-induced mammary carcinogenesis....... No differences in maternal serum estradiol (P = 0.19) and IGF-1 levels (P = 0.15) at GD 19 or birth weight among the milk and water groups were seen, but estradiol, and IGF-1 levels and birth weight were numerically higher in the LIM than in the HIM group. Puberty onset occurred earlier in the LIM offspring than...... in controls (P = 0.03). Although the high isoflavone content seemed to prevent the effect on circulating estradiol and IGF-1 levels and advanced puberty onset seen in the LIM group, HIM increased DMBA-DNA adducts in the mammary gland and tended to increase mammary tumorigenesis. In contrast, offspring exposed...

  12. Obesity And Laboratory Diets Affects Tissue Malondialdehyde (MDA) Levels In Obese Rats

    Science.gov (United States)

    Chowdhury, Parimal; Scott, Joseph; Holley, Andy; Hakkak, Reza

    2010-04-01

    This study was conducted to investigate the interaction of obesity and laboratory diets on tissue malondialdehyde levels in rats. Female Zucker obese and lean rats were maintained on either regular grain-based diet or purified casein diet for two weeks, orally gavaged at day 50 with 65 mg/kg DMBA and sacrificed 24 hrs later. Malondialdehyde (MDA) levels were measured in blood and harvested tissues. Data were recorded as mean ± SEM and analyzed statistically. Results show that the obese group on purified casein diet had reduction of MDA levels in the brain, duodenum, liver, lung and kidney tissues as compared to lean group, p <0.05. Obese group on grain-based diet showed significant increase in MDA levels only in the duodenum, p <0.05. We conclude that dietary intervention differentially affects the oxidative markers in obese rats. It appears that purified casein diets were more effective than grain-based diet in reduction of oxidative stress in obese rats.

  13. Mammalian cell biology

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Progress is reported on studies of the molecular biology and functional changes in cultured mammalian cells following exposure to x radiation, uv radiation, fission neutrons, or various chemical environmental pollutants alone or in combinations. Emphasis was placed on the separate and combined effects of polycyclic aromatic hydrocarbons released during combustion of fossil fuels and ionizing and nonionizing radiations. Sun lamps, which emit a continuous spectrum of near ultraviolet light of 290 nm to 315 nm were used for studies of predictive cell killing due to sunlight. Results showed that exposure to uv light (254 nm) may not be adequate to predict effects produced by sunlight. Data are included from studies on single-strand breaks and repair in DNA of cultured hamster cells exposed to uv or nearultraviolet light. The possible interactions of the polycyclic aromatic hydrocarbon 7,12-dimethylbenz(a)-anthracene (DmBA) alone or combined with exposure to x radiation, uv radiation (254 nm) or near ultraviolet simulating sunlight were compared for effects on cell survival

  14. Collected literature on isoflavones and chronic diseases

    Directory of Open Access Journals (Sweden)

    Katie A. Miller

    2016-12-01

    Full Text Available Isoflavones are organic compounds, which have been linked to the health benefits and prevention of many diseases. Common isoflavones are genistein, daidzein, and glycitein. Genistein has been researched in regard to its effect on the reduction of menopausal symptoms and reduction of cardiovascular risk factors in osteopenic, post-menopausal women. Research on daidzein focuses on bone mineral density implications in post-menopausal women, therapeutic effects early in prostate cancer, and protection against DMBA-induced mammary carcinogenesis. The most recent research on daidzein has implications for its effect on cardiovascular risk reduction. Research on glycitein focuses on it bioavailability, as well as its role in angiogenesis and invasion of malignant glioma cells. The health benefits of these specific isoflavones are instrumental in the prevention and treatment of many diseases. This review of literature focuses on the effects of genistein, daidzein, and glycitein on health outcomes, such as breast cancer, cardiovascular disease, and prostate cancer.

  15. 16α-[77Br]bromoestradiol-17β: a high specific-activity, gamma-emitting tracer with uptake in rat uterus and induced mammary tumors

    International Nuclear Information System (INIS)

    Katzenellenbogen, J.A.; Senderoff, S.G.; McElvany, K.D.; O'Brien, H.A. Jr.; Welch, M.J.

    1981-01-01

    16α-[ 77 Br]bromoestradiol-17β (compound 1) has been synthesized by radiobromination of estrone enoldiacetate. Tissue uptake studies performed 1 hr after administration of compound 1 to immature or mature female rats showed uterus-to-blood ratios of 13, with nontarget tissue-to-blood ratios ranging from 0.6 to 2. Co-administration of unlabeled estradiol caused a selective depression in the uterine uptake with no effect on nontarget tissue uptake. In adult animals bearing adenocarcinomas induced by DMBA (7,12-dimethylbenz(a)anthracene), tumor-to-blood ratios of 6.3 were obtained, this uptake also being depressed in animals treated with unlabeled estradiol. The studies demonstrate that compound 1 has suitable binding properties and sufficiently high specific activity so that its uptake in estrogen target tissues in vivo is mediated primarily by the estrogen receptor. Furthermore, they suggest that this compound may be suitable for imaging human breast tumors that contain estrogen receptors

  16. 16 alpha-[77Br]bromoestradiol-17 beta: a high specific-activity, gamma-emitting tracer with uptake in rat uterus and uterus and induced mammary tumors

    International Nuclear Information System (INIS)

    Katzenellenbogen, J.A.; Senderoff, S.G.; McElvany, K.D.; O'Brien, H.A. Jr.; Welch, M.J.

    1981-01-01

    16 alpha-[77Br]bromoestradiol-17 beta (Compound 1) has been synthesized by radiobromination of estrone enoldiacetate. Tissue uptake studies performed 1 h after administration of Compound 1 to immature or mature female rats showed uterus-to-blood ratios of 13, with nontarget issue-to-blood ratios ranging from 0.6 to 2. Co-administration of unlabelled estradiol caused a selective depression in the uterine uptake with no effect on nontarget tissue uptake. In adult animals bearing adenocarcinomas induced by DMBA (7,12-dimethylbenz(a)anthracene), tumor-to-blood ratios of 6.3 were obtained, this uptake also being depressed in animals treated with unlabeled estradiol. The studies demonstrate that Compound 1 has suitable binding properties and sufficiently high specific activity so that its uptake in estrogen target tissues in vivo is mediated primarily by the estrogen receptor. Furthermore, they suggest that this compound may be suitable for imaging human breast tumors that contain estrogen receptors

  17. Effect of asoka on the intracellular glutathione levels and skin tumour promotion in mice.

    Science.gov (United States)

    Varghese, C D; Nair, S C; Panikkar, B; Panikkar, K R

    1993-04-15

    The bark of Saraka asoca (asoka) is commonly used to treat various diseases by the Indian system of medicine and in Sri Lanka. Further purification and chemical analysis of the active compound from the bark extract of asoka showed that (-)-epicatechin was responsible for the observed antitumour/anticarcinogenic activity. Papilloma formation in mice initiated with 7,12-dimethylbenz[a]anthracene (DMBA) and promoted using croton oil was inhibited by the topical application of 100 mg/kg body weight (b.w.) of (-)-epicatechin isolated from asoka bark extract. Oral administration of the same dose restricted the growth of s.c. injected 20 methylcholanthrene (MCA) induced soil tissue fibrosarcomas significantly in mice. Elevations of almost 2-4-fold in the intracellular reduced glutathione and related enzymes viz., glutathione reductase and glutathione S-transferase of sarcoma-180 tumour cells were noted in the presence of 1 microgram/ml of (-)-epicatechin, further highlighting its antiproliferative effect.

  18. The properties of red seaweed (Kappaphycus alvarezii) and its effect on mammary carcinogenesis.

    Science.gov (United States)

    Chang, Vi-Sion; Okechukwu, Patrick N; Teo, Swee-Sen

    2017-03-01

    The edible red seaweed (Kappaphycus alvarezii) is one of the algae species which was found to be rich in nutrients and nutraceutical. Hence, K. alvarezii may have the ability to suppress cancer through its antiproliferative properties. The aim of this study was to investigate the potential compounds of K. alvarezii, cytotoxicity properties of K. alvarezii extract on breast cancer cell line (MCF-7), investigated toxicity effect of high dosage K. alvarezii extract in rats and determined the effect of K. alvarezii on 7, 12-dimethylbenz[a]anthracene (DMBA) mammary carcinogenesis in rats. The method of LCMS/MS and MTT assay were used. For animal study, sub-chronic toxicity method was used, the rats were supplemented with 2000mg/kg body weight daily of K. alvarezii crude extracts by oral gavage. For the anticancer effect of K. alvarezii crude extracts, this study consisted of three groups of the experimental, untreated and normal group of rats. The experimental and untreated groups of rats were induced with mammary tumour with DMBA. The experimental group of rats was given with K. alvarezii crude extracts orally. The results were being used to compare with the untreated group of rats and normal group of rats. All the rats were fed with standard diet and water ad libitum. Mortality, behavior changes and tumour sizes were observed specifically. The differences between the three groups of rats were evaluated by using the ANOVA test. By using LCMS/MS method, six unknown compounds were analysed. K. alvarezii crude extract reduced the cell viability of MCF-7 from 84.91% to 0.81% and the IC 50 value is 4.1±0.69mg/mL. For sub-chronic and heavy metal toxicity studies, no significant difference was found in haematological and biochemical values of the control group and experimental group. The growth rate of tumours in the untreated group of rats was found significantly higher than the experimental group of rats. Besides that, the white blood cells level in untreated group was

  19. Alterations in the metabolism of benzo[a]pyrene in syrian hamster embryo (SHE) cells pretreated with phenolic antioxidants

    International Nuclear Information System (INIS)

    Strniste, G.F.; Okinaka, R.T.; Chen, D.J.

    1983-01-01

    Inhibition of chemical- or radiation-induced neoplasia has been observed in animals whose diets were supplemented with antioxidants commonly used as food additives. Inhibition of the carcinogenicity of benzo[a]pyrene (BaP) or of 7,12-dimenthylbenz[a]anthracene (DMBA) - in rats has been achieved by the addition of the phenolic antioxidants butylated hydroxyanisole (BHA) or butylated hydroxytoluene (BHT) to the diet. Our data suggest that in SHE cells antioxidants inhibit the overall metabolism of BaP to its various oxidized moieties including 7,8-diol- and 7,8,9,10-tetrol-BaP. A plausible explanation for our results with SHE cells is that the antioxidants interact directly with AHH, thus inhibiting AHH metabolic capacity. From analysis of nuclear material from SHE cells (+- antioxidants) incubated for 36 hours with BaP at 1 μg/ml, it is calculated that 4.6, 2.4 and 2.9 pmol BaP are bound to the DNA isolated from 10 7 nuclei of control, BHA-(20 μg/ml) and p-MP-(10 μg/ml) treated cultures, respectively

  20. Dominant Role of HPV16 E7 in Anal Carcinogenesis

    Science.gov (United States)

    Thomas, Marie K.; Pitot, Henry C.; Liem, Amy; Lambert, Paul F.

    2011-01-01

    Ninety percent of anal cancer is associated with human papilloma viruses (HPVs). Using our previously established HPV transgenic mouse model for anal cancer, we tested the role of the individual oncogenes E6 and E7. K14E6 and K14E7 transgenic mice were treated with dimethylbenz[a]anthracene (DMBA) to the anal canal and compared to matched nontransgenic and doubly transgenic K14E6/E7 mice. K14E7 and K14E6/E7 transgenic mice developed anal tumors (papillomas, atypias and carcinomas combined) at significantly higher rates (88% and 100%, respectively) than either K14E6 or NTG mice (18% and 19%, respectively). Likewise, K14E7 and K14E6/E7 transgenic mice developed frank cancer (carcinomas) at significantly higher rates (85% and 85%, respectively) than either K14E6 or NTG mice (18% and 10%, respectively). These findings indicate that E7 is the more potent oncogene in anal cancer caused by HPVs. PMID:21999991

  1. Modifying factors in rat mammary gland carcinogenesis

    International Nuclear Information System (INIS)

    Shellabarger, C.J.

    1975-01-01

    The spontaneous incidence of mammary adenocarcinomas and mammary fibroadenomas in rats was found to be related to the strain of rat studied. Strains of rats that are sensitive to chemical carcinogens in regard to induced mammary neoplasia tend to be the same strains of rats that are sensitive to radiation. Methylcholantrene (MCA) and x-rays appeared to act in an additive fashion on the induction of mammary adenocarcinomas when they were given together. Lactating and older rats lose responsiveness to chemical carcinogens but do not lose responsiveness to radiation. Radiation appears to act in a scopal fashion in the induction of mammary neoplasia. Mammary neoplasia induction was not changed when low LET radiation was split into 2 equal fractions and high LET radiation was more effective than low LET radiation in inducing mammary neoplasia. It is suggested that DMBA can act as an initiator for the induction of mammary adenocarcinomas, that phorbol can act as a promotor, and that viruses may induce mammary neoplasia. Diethylstilbestrol (DES) and radiation appeared to act synergistically in the induction of mammary adenocarcinomas in one strain of rat but not in another strain. (U.S.)

  2. [Observation on alpha-SMA during Erigeron Breviscapus (Vant) Hand-Mazz obstructs the evolution of carcinogenesis of golden hamster cheek pouch].

    Science.gov (United States)

    Zhou, C T; Zhang, S L; Ding, R Y; Hua, L; Zhong, W J

    2000-06-01

    To observe dynamically that Erigeron Breviscapus (Vant) Hand-Mazz (HEr) affects the expression of alpha-smooth muscle actin (alpha-SMA). To discuss the probable mechanism of obstructing leukoplakia carcinogenesis of this medicine. 120 golden hamsters were randomly divided into model group (48), HEr group (48) and control group (6). HEr was applied to obstruct the evolution of carcinogenesis of golden hamster cheek pouch. Immunohistochemistry was used to detect the expression level of alpha-SMA with cheek pouch specimen that besmears DMBA in 4-9 weeks. Results were compared with model group. Vessel density dyed with alpha-SMA continuously of HEr group was 65.76 significantly higher than that of model group 42.12 (P<0.001). High classification cases in HEr group were much more than model group when cases were divided into five groups as follow: 100%, 50%, 20%, 10%, 3% (P<0.01). HEr can raise the expression level of alpha-SMA exactly during the evolution of leukoplakia carcinogenesis of golden hamster, which shows that this medicine obstructs carcinogenesis by keeping the normal physiological function of vascular myoepithelial cell and integrity of vascular basement membrane.

  3. Vaccinia virus, herpes simplex virus, and carcinogens induce DNA amplification in a human cell line and support replication of a helpervirus dependent parvovirus

    International Nuclear Information System (INIS)

    Schlehofer, J.R.; Ehrbar, M.; zur Hausen, H.

    1986-01-01

    The SV40-transformed human kidney cell line, NB-E, amplifies integrated as well as episomal SV40 DNA upon treatment with chemical (DMBA) or physical (uv irradiation) carcinogens (initiators) as well as after infection with herpes simplex virus (HSV) type 1 or with vaccinia virus. In addition it is shown that vaccinia virus induces SV40 DNA amplification also in the SV40-transformed Chinese hamster embryo cell line, CO631. These findings demonstrate that human cells similar to Chinese hamster cells amplify integrated DNA sequences after treatment with carcinogens or infection with specific viruses. Furthermore, a poxvirus--vaccinia virus--similar to herpes group viruses induces DNA amplification. As reported for other systems, the vaccinia virus-induced DNA amplification in NB-E cells is inhibited by coinfection with adeno-associated virus (AAV) type 5. This is in line with previous studies on inhibition of carcinogen- or HSV-induced DNA amplification in CO631 cells. The experiments also demonstrate that vaccinia virus, in addition to herpes and adenoviruses acts as a helper virus for replication and structural antigen synthesis of AAV-5 in NB-E cells

  4. The change on the cell proliferation kinetics of the central and peripheral regions of DMBA induced hamster tongue cancer following irradiation

    International Nuclear Information System (INIS)

    Inoue, Toyoaki; Nasu, Masanori; Kai, Yasumasa; Furumoto, Keiichi

    1989-01-01

    A single Co-60 irradiation of 20 Gy was delivered to the tongue with carcinoma induced by 1%9, 10-dimethyl, 2-benzanthracene acetone solution in hamsters. One and 3 days after irradiation, cell kinetics of the central and peripheral regions was investigated by H-3 thymidine labelling method. Both initial labelling (L) and mitosis (M) indices were high in the central region and low in the peripheral region before irradiation. One and 3 days after irradiation, the L index was decreased by 43% in the central region; however, this was slight in the peripheral region. The M index after irradiation was decreased for the entire tumor--it was slightly decreased in the central region, and increased twofold in the peripheral region. Regarding cell cycle time (Tc), G-2 phase (TG-2), and mitosis phase (Tm), there was no difference between the central and peripheral regions before irradiation. In both the central and peripheral regions, Tc was delayed by 3 hours on Day one, but shortened by 6.5 hours on Day 3. The TG-2 in both regions were delayed by 2 hours on Day one and by 3 days on Day 3. The Tm increased 1.6-fold in the central region and 2.1-fold in the peripheral region on Day one. Similar tendency was seen on Day 3. DNA synthesis phase before and after irradiation did not differ in either the central or peripheral region. Similarly, no difference in G-1 phase (TG-1) in either region was observed before and one day after irradiation. However, the TG-1 in both regions was decreased by as much as 90% on Day 3. (N.K.)

  5. "Inhibitory Effect of Tannic Acid from Nutgall on Iron-Dextran Augmented 7,12-Dimethyl Benz(AAnthracene-Initiated and Croton Oil-Promoted Skin Carcinogenesis "

    Directory of Open Access Journals (Sweden)

    Abbas Delazar

    2003-08-01

    Full Text Available Tannic acid (TA is naturally occurring polyphenols present in fruits and vegetables. In this study, inhibition of the carcinogenic potential of croton oil in normal and iron overloaded mice skin by TA is reported. Albino Swiss mice were given iron-dextran for two weeks and were pretreated with a single topical application of tannic acid. After one hour tumors were initiated by a single dose of 7,12- dimethylbenz(aanthracene (DMBA the promoting agent croton oil was applied twice a week for 30 weeks. The appearance, number and percent tumor incidences were recorded. When compared to control groups, the pretreated groups showed a significant high inhibition of tumors incidences. Biochemical studies in mice skin tissues were based on the measurement of lipid peroxidation (LPO. TA diminished cutaneous LPO level in mice skin as compared to the untreated groups. This study showed that TA inhibits the augmentation potentials of croton oil and iron dextran significantly. A depletion in LPO levels in TA pretreated groups indicates that excessive generated oxidants in the mice skin tissues may be quenched by TA because of chelation of redox active iron and its faster elimination from the body. It is supposed that inhibition of iron mediated oxidative stress by TA may be responsible for diminishment of cutaneous tumorigenesis.

  6. The Effect of VPA on Increasing Radiosensitivity in Osteosarcoma Cells and Primary-Culture Cells from Chemical Carcinogen-Induced Breast Cancer in Rats.

    Science.gov (United States)

    Liu, Guochao; Wang, Hui; Zhang, Fengmei; Tian, Youjia; Tian, Zhujun; Cai, Zuchao; Lim, David; Feng, Zhihui

    2017-05-10

    This study explored whether valproic acid (VPA, a histone deacetylase inhibitor) could radiosensitize osteosarcoma and primary-culture tumor cells, and determined the mechanism of VPA-induced radiosensitization. The working system included osteosarcoma cells (U2OS) and primary-culture cells from chemical carcinogen (DMBA)-induced breast cancer in rats; and clonogenic survival, immunofluorescence, fluorescent in situ hybridization (FISH) for chromosome aberrations, and comet assays were used in this study. It was found that VPA at the safe or critical safe concentration of 0.5 or 1.0 mM VPA could result in the accumulation of more ionizing radiation (IR)-induced DNA double strand breaks, and increase the cell radiosensitivity. VPA-induced radiosensitivity was associated with the inhibition of DNA repair activity in the working systems. In addition, the chromosome aberrations including chromosome breaks, chromatid breaks, and radial structures significantly increased after the combination treatment of VPA and IR. Importantly, the results obtained by primary-culture cells from the tissue of chemical carcinogen-induced breast cancer in rats further confirmed our findings. The data in this study demonstrated that VPA at a safe dose was a radiosensitizer for osteosarcoma and primary-culture tumor cells through suppressing DNA-double strand breaks repair function.

  7. Biodistribution and breast tumor uptake of 16α-[18F]-fluoro-17β-estradiol in rat

    International Nuclear Information System (INIS)

    Sasaki, Masayuki; Fukumura, Toshimitsu; Kuwabara, Yasuo; Yoshida, Tsuyoshi; Nakagawa, Makoto; Ichiya, Yuichi; Masuda, Kouji

    2000-01-01

    To evaluate the usefulness of 16α-[ 18 F]-fluoro-17β-estradiol (FES) for the assessment of estrogen receptor (ER), we examined the tissue distribution and kinetics of FES in immature female Sprague-Dawley rats and then examined FES uptake in rat breast tumors induced by 7,12-dimethylbenz(a)anthracene (DMBA). The FES uptake by the uterus, an ER-rich tissue, was highly selective and it was 3.34±0.79%ID/g at 60 minutes and 1.57±0.57%ID/g at 120 minutes after injection. The FES uptakes in ER-negative tissues were 0.12±0.05%ID/g or less and 0.05±0.03%ID/g or less, respectively. Coadministration of unlabeled β-estradiol showed marked depression of uterine FES uptake. The FES uptake by rat breast tumors was 0.14±0.06%ID/g at 60 min and 0.12±0.09%ID/g at 120 min. The FES uptake by rat breast tumors correlated with the ER concentration (r=0.45, p<0.05). In conclusion, these results suggest that the FES uptake by tissue is mainly ER mediated and FES is thus useful for detecting ER positive breast tumors. (author)

  8. Assessment of female reproductive endpoints in Sprague-Dawley rats developmentally exposed to Diuron: potential ovary toxicity.

    Science.gov (United States)

    Grassi, Tony Fernando; Guerra, Marina Trevisan; Perobelli, Juliana Elaine; de Toledo, Fabíola Choqueta; da Silva, Denise Salioni; De Grava Kempinas, Wilma; Barbisan, Luís Fernando

    2011-10-01

    Diuron is widely used in agriculture but its deleterious effects on the reproductive system and mammary gland are still poorly understood. This study evaluated whether early-life-stage exposure to Diuron alters puberty onset or susceptibility to mammary carcinogenesis in female Sprague-Dawley rats. Pregnant rats received basal diet or diet containing Diuron at 500, 750, and 1,250 ppm, from gestational day 12 to the end of lactation (postnatal day 21 [PND21]). After weaning, female offspring continued receiving basal diet or diet containing Diuron until PND 51. At PND 51, female Sprague-Dawley offspring received a single dose of 50 mg/kg b.w. of 7,12-dimethylbenz(a)anthracene (DMBA) for initiation of mammary carcinogenesis. The animals were sacrificed on PND 51, 75, and 226 to 233 (week 25) for mammary gland morphology, reproductive organs and tumor analysis, respectively. There were no significant differences among groups on vaginal opening, estrous cycle, mammary morphology, or carcinogenesis. However, reductions in ovary weight and corpora lutea were observed at PND 75 in the group treated with Diuron at 1,250 ppm. The findings suggesting that Diuron exposure (1,250 ppm) may have been potentially toxic to the ovaries. © 2011 Wiley Periodicals, Inc.

  9. Improve efficacy of topical ALA-PDT by calcipotriol through up-regulation of coproporphyrinogen oxidase.

    Science.gov (United States)

    Yang, Deng-Fu; Chen, Jia-Haur; Chiang, Chun-Pin; Huang, Zheng; Lee, Jeng-Woei; Liu, Chung-Ji; Chang, Junn-Liang; Hsu, Yih-Chih

    2014-09-01

    Topical 5-aminolevulinic acid-mediated photodynamic therapy (topical ALA-PDT) is effective for treating oral precancerous lesions. The aim of this in vivo and in vitro study was to examine whether the efficacy of topical ALA-PDT could be further improved by calcipotriol (CAL). Precancerous lesions in the buccal pouch of hamsters were induced by dimethylbenz(a)anthracene (DMBA). Lesions were treated with multiple topical ALA-PDT with or without CAL pretreatment. ALA-induced protoporphyrine IX (PpIX) was monitored by in situ fluorescence measurement. The effect of CAL on heme-related enzymes (CPOX, PPOX, and FECH) were examined in an in vitro model using human squamous cell carcinoma (SCC) cells (SCC4, SAS) using Western blots. Fluorescence spectroscopy revealed that PpIX reached its peak level in precancerous epithelial cells of buccal pouch at 2.5 or 3.5h without or with CAL pretreatment, respectively. Both treatment regimens showed similar response rates, but the complete response was achieved after 5 times of ALA-PDT and 3 times of CAL-ALA-PDT (plevel. Topical CAL can improve the efficacy of ALA-PDT in treating precancerous lesions, likely through the increase in CPOX level and in PpIX production. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. The role of chronic acanthosis and subacute inflammation in tumor promotion in CD-1 mice by petroleum middle distillates.

    Science.gov (United States)

    Skisak, C

    1991-07-01

    An initiation-promotion bioassay using CD-1 mice was conducted to examine the role of chronic acanthosis and inflammation in tumor promotion by petroleum middle distillates (MD). Test groups were initiated with 7,12-dimethylbenz[a]anthracene (DMBA). Promotion with MD consisted of twice weekly treatments for 25 weeks with either 25 or 50 microliters, 50 microliters + daily treatment with 15 micrograms dexamethasone, 50 microliters + postapplication washings, or 100 microliters. Three mice from each group were euthanized at 21-day intervals (24 total per group). The skin from interim euthanized mice was examined histopathologically for tumors, acanthosis, and subacute inflammation. Tumor incidence at study termination was as follows: 25 microliters (45%), 50 microliters (43%), 50 microliters + dexamethasone (0%), 50 microliters + washing (70%), and 100 microliters (81%). A correlation of greater than 0.93 was observed at all intervals between tumor incidence and cumulative group mean degrees of acanthosis in interim euthanized mice. The correlation between subacute inflammation at early through midstudy interval weeks and tumor incidence at study termination was poor. These results support the hypothesis that induction of a lasting, albeit mild, hyperplasia is an essential, but not sufficient requirement for tumor promotion. Furthermore, subacute inflammation does not appear to be a significant factor in tumor promotion by petroleum MD.

  11. Estudio sobre tumores melanóticos del jámster sirio. II. Efecto de la edad del jámster dorado (Mesocricetus auratus sobre la inducción de tumores melanóticos por el 9,10 dimetilbenzantraceno

    Directory of Open Access Journals (Sweden)

    José Perea Sasiaín

    1966-10-01

    Full Text Available En medicina humana es bien conocida la influencia de la edad sobre la frecuencia del melanoma maligno: este tumor es muy infrecuente, si no excepcional, antes de la pubertad. Los pocos casos documentados de transmisión transplacentaria de tumores, han sido en su mayoría melanomas, lo cual prueba que el infante es susceptible al crecimiento de trasplantes de este tumor, proveniente de la madre. En el jamster dorado se han inducido tumores melanóticos mediante una sola aplicación de 9,10 dimetilbenzantraceno (D MBA. Estos tumores no son considerados malignos por su aspecto histológico, no dar metástasis, ni producir la muerte del animal, ni ser transplantables   regularmente a huéspedes homólogos. Son, sin embargo, de grande importancia para el estudio de la inducción de la melanogénesis. El presente estudio fue realizado "con el fin de establecer la influencia que la edad pudiera tener sobre la cantidad de tumores inducidos por el DMBA. Se consideró en particular que el jámster dorado no alcanza su madurez sexual hasta después del mes (45-60 días, descontando casos excepcionales como el observado a los 28 días.

  12. The value of DCE-MRI in assessing histopathological and molecular biological features in induced rat epithelial ovarian carcinomas.

    Science.gov (United States)

    Yuan, Su Juan; Qiao, Tian Kui; Qiang, Jin Wei; Cai, Song Qi; Li, Ruo Kun

    2017-09-26

    To investigate dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) for assessing histopathological and molecular biological features in induced rat epithelial ovarian carcinomas (EOCs). 7,12-dimethylbenz[A]anthracene (DMBA) was applied to induce EOCs in situ in 46 SD rats. Conventional MRI and DCE-MRI were performed to evaluate the morphology and perfusion features of the tumors, including the time-signal intensity curve (TIC), volume transfer constant (K trans ), rate constant (K ep ), extravascular extracellular space volume ratio (V e ) and initial area under the curve (IAUC). DCE-MRI parameters were correlated with histological grade, microvascular density (MVD), vascular endothelial growth factor (VEGF) and fraction of Ki67-positive cells and the serum level of cancer antigen 125 (CA125). Thirty-five of the 46 rats developed EOCs. DCE-MRI showed type III TIC more frequently than type II (29/35 vs. 6/35, p values showed significant differences in different histological grades in overall and pairwise comparisons except for IAUC in grade 2 vs. grade 3 (all p values among the three grade groups (p > 0.05). K trans , K ep and IAUC values were positively correlated with MVD, VEGF and Ki67 expression (all p  0.05). TIC types and perfusion parameters of DCE-MRI can reflect tumor grade, angiogenesis and cell proliferation to some extent, thereby helping treatment planning and predicting prognosis.

  13. Downregulation of keratin 76 expression during oral carcinogenesis of human, hamster and mouse.

    Directory of Open Access Journals (Sweden)

    Srikant Ambatipudi

    Full Text Available Keratins are structural marker proteins with tissue specific expression; however, recent reports indicate their involvement in cancer progression. Previous study from our lab revealed deregulation of many genes related to structural molecular integrity including KRT76. Here we evaluate the role of KRT76 downregulation in oral precancer and cancer development.We evaluated KRT76 expression by qRT-PCR in normal and tumor tissues of the oral cavity. We also analyzed K76 expression by immunohistochemistry in normal, oral precancerous lesion (OPL, oral squamous cell carcinoma (OSCC and in hamster model of oral carcinogenesis. Further, functional implication of KRT76 loss was confirmed using KRT76-knockout (KO mice.We observed a strong association of reduced K76 expression with increased risk of OPL and OSCC development. The buccal epithelium of DMBA treated hamsters showed a similar trend. Oral cavity of KRT76-KO mice showed preneoplastic changes in the gingivobuccal epithelium while no pathological changes were observed in KRT76 negative tissues such as tongue.The present study demonstrates loss of KRT76 in oral carcinogenesis. The KRT76-KO mice data underlines the potential of KRT76 being an early event although this loss is not sufficient to drive the development of oral cancers. Thus, future studies to investigate the contributing role of KRT76 in light of other tumor driving events are warranted.

  14. Poly-MVA attenuates 7,12- dimethylbenz[a]anthracene initiated and croton oil promoted skin papilloma formation on mice skin.

    Science.gov (United States)

    Veena, Ravindran K; Ajith, Thekkuttuparambil A; Janardhanan, Kainoor K; Antonawich, Francis

    2017-09-01

    Chemopreventive agents which exhibit activities such as anti-inflammation, inhibition of carcinogen induced mutagenesis and scavenging of free radical might play a decisive role in the inhibition of chemical carcinogenesis either at the initiation or promotion stage. Many synthesized palladium (Pd) complexes tested experimentally for antitumor activity are found effective. Poly-MVA is a liquid blend preparation containing B complex vitamins, ruthenium with Pd complexed with alpha lipoic acid as the major ingredients. The antitumor effect of Poly-MVA was evaluated against 7,12-dimethylbenz[a] anthracene-initiated croton oil-promoted papilloma formation on mice skin. Skin tumor was initiated with a single application of 390 nmol of DMBA in 20 µl acetone. The effect of Poly-MVA against croton oil- induced inflammation and lipid peroxidation on the mice skin was also evaluated. Topical application of Poly-MVA (100 µl, twice weekly for 18 weeks) 30 minutes prior to each croton oil application, significantly decreased the tumor incidence (11%) and the average number of tumor per animals. Application of Poly-MVA (100 µl) before croton oil significantly (p < 0.05) protected the mouse skin from inflammation (36%) and lipid peroxidation (14%) when compared to the croton oil alone treated group. Experimental results indicate that Poly-MVA attenuate the tumor promoting effects of croton oil and the effect may probably be due to its anti-inflammatory and antioxidant activity.

  15. The role of dermal irritation in the skin tumor promoting activity of petroleum middle distillates.

    Science.gov (United States)

    Nessel, C S; Freeman, J J; Forgash, R C; McKee, R H

    1999-05-01

    Petroleum middle distillates (PMDs), a class of hydrocarbons which boil between 350-700 degrees F, are tumor promoters in mouse skin. The promotional activity is produced under conditions that also result in local changes, including chronic irritation and epidermal hyperplasia. The present study was conducted by comparing equal weekly doses of irritating and minimally or nonirritating test materials, to assess whether tumor promotion was a secondary response to these effects. Four PMDs, C10-C14 normal paraffins (NP), lightly refined paraffinic oil (LRPO), Jet Fuel A (JF), and steam-cracked gas oil (SCGO), were evaluated. Test materials were applied undiluted (2x/week) or as 28.6% (7x/week) or 50% (4x/week) concentrations in mineral oil for 52 weeks following initiation with dimethylbenzanthracene (DMBA). When applied undiluted, all materials produced moderate irritation and significant increase in tumor incidence. When NP, LRPO, or JF were applied in mineral oil diluent, skin irritation was generally ameliorated and few, if any, tumors were produced. SCGO was irritating and produced a significant increase in tumor frequency when administered in mineral-oil diluent. These data indicate that the promotional activity of straight-run PMDs is likely related to chronic irritation at the application site and not to dose. Thus, when used appropriately in the absence of prolonged irritation, these materials should not present a tumorigenic hazard to humans.

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

    Science.gov (United States)

    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.

  17. A Bayesian statistical analysis of mouse dermal tumor promotion assay data for evaluating cigarette smoke condensate.

    Science.gov (United States)

    Kathman, Steven J; Potts, Ryan J; Ayres, Paul H; Harp, Paul R; Wilson, Cody L; Garner, Charles D

    2010-10-01

    The mouse dermal assay has long been used to assess the dermal tumorigenicity of cigarette smoke condensate (CSC). This mouse skin model has been developed for use in carcinogenicity testing utilizing the SENCAR mouse as the standard strain. Though the model has limitations, it remains as the most relevant method available to study the dermal tumor promoting potential of mainstream cigarette smoke. In the typical SENCAR mouse CSC bioassay, CSC is applied for 29 weeks following the application of a tumor initiator such as 7,12-dimethylbenz[a]anthracene (DMBA). Several endpoints are considered for analysis including: the percentage of animals with at least one mass, latency, and number of masses per animal. In this paper, a relatively straightforward analytic model and procedure is presented for analyzing the time course of the incidence of masses. The procedure considered here takes advantage of Bayesian statistical techniques, which provide powerful methods for model fitting and simulation. Two datasets are analyzed to illustrate how the model fits the data, how well the model may perform in predicting data from such trials, and how the model may be used as a decision tool when comparing the dermal tumorigenicity of cigarette smoke condensate from multiple cigarette types. The analysis presented here was developed as a statistical decision tool for differentiating between two or more prototype products based on the dermal tumorigenicity. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  18. Correlation of regional disease and in vivo PO2 in rat mammary adenocarcinoma.

    Science.gov (United States)

    Cole, M A; Crawford, D W; Warner, N E; Puffer, H W

    1983-07-01

    A knowledge of the distribution of oxygen tension (PO2) and vascularization in neoplasia has been fundamental to understanding relationships between tumor growth, hypoxia, and therapy. We have combined recessed oxygen microcathode and freeze-substitution techniques to correlate in situ PO2 profiles and morphologic features in 7,12-dimethylbenz(a)anthracene (DMBA) tumors in rats. Overlying connective tissue of transplanted tumor was exposed by a 1-2 mm incision and a cross-stitch pattern demarcated electrode puncture sites for histologic reference. Three buffered salt solutions (BSS) with different PO2 were each allowed to flow through a well over the tumor where electrodes were placed for calibration. Zero electrode oxygen current was recorded from a buffered yeast-agar mixture of zero torr. PO2 was recorded at 5-mu intervals to approximately 1-2 mm. Atmospheric contamination was eliminated by continuous well flow of BSS, 30 torr. Finally, the tumor and surrounding tissues were quick-frozen in vivo with Freon 22 and liquid nitrogen. The tissue block was freeze-substituted and sectioned. PO2 profiles were superimposed onto correspondingly scaled photomicrographs. A viable periphery with a PO2 range of 50-82 torr and a transition to necrotic areas of PO2, 2-13 torr were observed. This transition was characterized by PO2 gradients within distances of 50-300 mu at variable puncture depths. This technique should be useful in further studies of growth, necrosis, and therapy.

  19. Melatonin Reduces Angiogenesis in Serous Papillary Ovarian Carcinoma of Ethanol-Preferring Rats

    Science.gov (United States)

    Zonta, Yohan Ricci; Martinez, Marcelo; Camargo, Isabel Cristina C.; Domeniconi, Raquel F.; Lupi Júnior, Luiz Antonio; Pinheiro, Patricia Fernanda F.; Reiter, Russel J.; Martinez, Francisco Eduardo; Chuffa, Luiz Gustavo A.

    2017-01-01

    Angiogenesis is a hallmark of ovarian cancer (OC); the ingrowth of blood vessels promotes rapid cell growth and the associated metastasis. Melatonin is a well-characterized indoleamine that possesses important anti-angiogenic properties in a set of aggressive solid tumors. Herein, we evaluated the role of melatonin therapy on the angiogenic signaling pathway in OC of an ethanol-preferring rat model that mimics the same pathophysiological conditions occurring in women. OC was chemically induced with a single injection of 7,12-dimethylbenz(a)anthracene (DMBA) under the ovarian bursa. After the rats developed serous papillary OC, half of the animals received intraperitoneal injections of melatonin (200 µg/100 g body weight/day) for 60 days. Melatonin-treated animals showed a significant reduction in OC size and microvessel density. Serum levels of melatonin were higher following therapy, and the expression of its receptor MT1 was significantly increased in OC-bearing rats, regardless of ethanol intake. TGFβ1, a transforming growth factor-beta1, was reduced only after melatonin treatment. Importantly, vascular endothelial growth factor (VEGF) was severely reduced after melatonin therapy in animals given or not given ethanol. Conversely, the levels of VEGF receptor 1 (VEGFR1) was diminished after ethanol consumption, regardless of melatonin therapy, and VEGFR2 was only reduced following melatonin. Hypoxia-inducible factor (HIF)-1α was augmented with ethanol consumption, and, notably, melatonin significantly reduced their levels. Collectively, our results suggest that melatonin attenuates angiogenesis in OC in an animal model of ethanol consumption; this provides a possible complementary therapeutic opportunity for concurrent OC chemotherapy. PMID:28398226

  20. In vitro and in vivo studies of the carcinogenic, toxic and genotoxic activities of the air pollutants SO/sub 2/ and NO/sub x/, separately and in combination with carcinogenic polycyclic aromatic hydrocarbons and N-nitrosamines

    Energy Technology Data Exchange (ETDEWEB)

    Zeller, W J; Klein, R G; Pool, B L; Schmezer, P; Horsch, F; Filby, W G; Fund, N; Gross, S; Hanisch, B; Kilz, E; Seidel, A [comps.

    1988-04-01

    In the course of our studies directed at elucidating biological effects of the air pollutants SO/sub 2/ and NO/sub x/ it was found, that the activity of lactate dehydrogenase (LDH) is inhibited by SO/sub 2/. This effect was observed in vitro and in vivo and is based on a sulfite- and not on a sulfate-mediated action. NO/sub x/ and SO/sub 2/ reduce DNA single strand breaks induced by B(a)P in fetal hamster lung cells in vitro and SO/sub 2/ reduces DNA single strand breaks induced by AMMN in primary cultures of rat hepatocytes. The postulated mechanisms of action are discussed. Sulfite itself induces DNA-amplification in SV40 transformed CO60 cells; but an increase in the amplification rate induced by B(a)P or 7,12-DMBA was not observed. The in vitro genotoxicity (DNA single strand breaks) of 3 nitrosamines (AMMN, NDMA, NMBzA) is reduced in rat hepatocytes from donor animals pretreated with 50 ppm SO/sub 2/ for 2 weeks. Inhalation of NO/sub x/ by rats reduced the activities of AHH, NDMA-D and GST in hepatocytes and of GST in lung cells. Following SO/sub 2/ inhalation NDMA-D activity in the liver is increased and GST activity in the lung is decreased. In a current in vivo long-term inhalation study of NDMA+-SO/sub 2/ or NO/sub x/ first tumors of the nasal cavity are already observed after a total dose of 2 mg NDMA/animal.

  1. Structure-dependent inhibitory effects of synthetic cannabinoids against 12-O-tetradecanoylphorbol-13-acetate-induced inflammation and skin tumour promotion in mice.

    Science.gov (United States)

    Nakajima, Jun'ichi; Nakae, Dai; Yasukawa, Ken

    2013-08-01

    Whether and how synthetic cannabinoids affect inflammation and carcinogenesis has not been well studied. The present study was thus conducted to assess effects of synthetic cannabinoids on inflammation and carcinogenesis in vivo in mice. Twenty-three analogues of synthetic cannabinoids were isolated from, and identified as adulterants in, illegal drugs distributed in the Tokyo metropolitan area, and were examined for their inhibitory effects on the induction of oedema in mouse ears by 12-O-tetradecanoylphorbol-13-acetate (TPA). Furthermore, selected cannabinoids, JWH-018, -122 and -210, were studied for their effects on carcinogenesis induced in mouse skin initiated with 7,12-dimethylbenz[a]anthracene (DMBA) and promoted by TPA. Among cannabinoids, naphthoylindoles mostly exhibited superior inhibitory effects against TPA-induced ear oedema and, especially, JWH-018, -122 and -210 showed potent activity with 50% inhibitory dose (ID50) values of 168, 346 and 542 nm, respectively (an activity corresponding to that of indometacin (ID50 = 908 nm)). Furthermore these three compounds also markedly suppressed the tumour-promoting activity of TPA. This is the first report indicating the structure-activity relationships for the anti-inflammatory activity of synthetic cannabinoids on TPA-induced inflammation in mice. Naphthoylindoles, JWH-018, -122 and -210, had the most potent anti-inflammatory activity and also markedly inhibited tumour promotion by TPA in the two-stage mouse skin carcinogenesis model. The present results suggest that synthetic cannabinoids, such as JWH-018, -122 and -210, may be used as cancer chemopreventive agents in the future. © 2013 Royal Pharmaceutical Society.

  2. Histopathological and in vivo evidence of regucalcin as a protective molecule in mammary gland carcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Marques, Ricardo; Vaz, Cátia V.; Maia, Cláudio J. [CICS-UBI, Health Sciences Research Centre, University of Beira Interior, Covilhã (Portugal); Gomes, Madalena [IPATIMUP, Institute of Molecular Pathology and Immunology, University of Porto, Porto (Portugal); Gama, Adelina [Department of Veterinary Sciences, Animal and Veterinary Science Research Center (CECAV), University of Trás-os-Montes and Alto Douro (UTAD) (Portugal); Alves, Gilberto; Santos, Cecília R. [CICS-UBI, Health Sciences Research Centre, University of Beira Interior, Covilhã (Portugal); Schmitt, Fernando [IPATIMUP, Institute of Molecular Pathology and Immunology, University of Porto, Porto (Portugal); Medical Faculty, University of Porto, Porto (Portugal); Department of Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto, Toronto (Canada); Department of Pathology, University Health Network, Toronto (Canada); Socorro, Sílvia, E-mail: ssocorro@fcsaude.ubi.pt [CICS-UBI, Health Sciences Research Centre, University of Beira Interior, Covilhã (Portugal)

    2015-01-15

    Regucalcin (RGN) is a calcium-binding protein, which has been shown to be underexpressed in cancer cases. This study aimed to determine the association of RGN expression with clinicopathological parameters of human breast cancer. In addition, the role of RGN in malignancy of mammary gland using transgenic rats overexpressing the protein (Tg-RGN) was investigated. Wild-type (Wt) and Tg-RGN rats were treated with 7,12-dimethylbenz[α]anthracene (DMBA). Carcinogen-induced tumors were histologically classified and the Ki67 proliferation index was estimated. Immunohistochemistry analysis showed that RGN immunoreactivity was negatively correlated with the histological grade of breast infiltrating ductal carcinoma suggesting that progression of breast cancer is associated with loss of RGN. Tg-RGN rats displayed lower incidence of carcinogen-induced mammary gland tumors, as well as lower incidence of invasive forms. Moreover, higher proliferation was observed in non-invasive tumors of Wt animals comparatively with Tg-RGN. Overexpression of RGN was associated with diminished expression of cell-cycle inhibitors and increased expression of apoptosis inducers. Augmented activity of apoptosis effector caspase-3 was found in the mammary gland of Tg-RGN. RGN overexpression protected from carcinogen-induced mammary gland tumor development and was linked with reduced proliferation and increased apoptosis. These findings indicated the protective role of RGN in the carcinogenesis of mammary gland. - Highlights: • RGN immunoreactivity was negatively correlated with breast cancer differentiation. • Transgenic overexpression of RGN diminished incidence of carcinogen-induced tumors. • Transgenic overexpression of RGN restricted proliferation and fostered apoptosis. • RGN has a protective role in the carcinogenesis of mammary gland.

  3. CENP-R acts bilaterally as a tumor suppressor and as an oncogene in the two-stage skin carcinogenesis model.

    Science.gov (United States)

    Okumura, Kazuhiro; Kagawa, Naoko; Saito, Megumi; Yoshizawa, Yasuhiro; Munakata, Haruka; Isogai, Eriko; Fukagawa, Tatsuo; Wakabayashi, Yuichi

    2017-11-01

    CENP-R is a component of the CENP-O complex, including CENP-O, CENP-P, CENP-Q, CENP-R, and CENP-U and is constitutively localized to kinetochores throughout the cell cycle in vertebrates. CENP-R-deficient chicken DT40 cells are viable and show a very minor effect on mitosis. To investigate the functional roles of CENP-R in vivo, we generated CENP-R-deficient mice (Cenp-r -/- ). Mice heterozygous or homozygous for Cenp-r null mutation are viable and healthy, with no apparent defect in growth and morphology, indicating Cenp-r is not essential for normal development. Accordingly, to investigate the role of the Cenp-r gene in skin carcinogenesis, we subjected Cenp-r -/- mice to the 7,12-dimethylbenz(a)anthracene (DMBA)/TPA chemical carcinogenesis protocol and monitored tumor development. As a result, Cenp-r -/- mice initially developed significantly more papillomas than control wild-type mice. However, papillomas in Cenp-r -/- mice showed a decrease of proliferative cells and an increase of apoptotic cells. As a result, they did not grow bigger and some papillomas showed substantial regression. Furthermore, papillomas in Cenp-r -/- mice showed lower frequency of malignant conversion to squamous cell carcinomas. These results indicate Cenp-r functions bilaterally in cancer development: during early developmental stages, Cenp-r functions as a tumor suppressor, but during the expansion and progression of papillomas it functions as a tumor-promoting factor. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  4. DNA repair in mammalian cells exposed to combinations of carcinogenic agents

    International Nuclear Information System (INIS)

    Setlow, R.B.; Ahmed, F.E.

    1979-01-01

    Cells defective in one or more aspects of repair are killed and often mutagenized more readily than normal cells by DNA damaging agents, and humans whose cells are deficient in repair are at an increased carcinogenic risk compared to normal individuals. The excision repair of uv induced pyrimidine dimers is a well studied system, but the details of the steps in this repair system are far from being understood in human cells. We know that there are a number of chemicals that mimic uv in that normal human cells repair DNA damage from both these agents and from uv by a long patch excision repair system, and that xeroderma pigmentosum cells defective in repair of uv are also defective in the repair of damage from these chemicals. The chemicals we have investigated are AAAF, 4-NQO, DMBA-epoxide, and ICR-170. We describe experiments, using several techniques, in which DNA excision repair is measured after treatment of various human cell strains with combinations of uv and these agents. If two agents have a common rate limiting step then, at doses high enough to saturate the repair system, one would expect the observed repair after a treatment with a combination of agents to be equal to that from one agent alone. Such is not the case for normal human or excision-deficient XP cells. In the former repair is additive and in the latter repair is usually appreciably less than that observed with either agent alone. Models that attempt to explain these surprising results involve complexes of enzymes and cofactors

  5. Biodistribution and metabolism of 16α-([/sup 18/F]-fluoro)-17β-estradiol

    International Nuclear Information System (INIS)

    Mathias, C.J.; Brodack, J.W.; Kilbourn, M.R.; Carlson, K.A.; Katzenellenbogen, J.A.; Welch, M.J.

    1985-01-01

    The uptake of receptor-mediated radiopharmaceuticals as measured by target to non-target uptake ratios depends upon many parameters. These include blood flow to the tissue, blood volume, receptor concentration as well as metabolism of the tracer. In a rat tumor model (DMBA) induced mammary tumors with high concentration of estrogen receptors) uptake of /sup 18/F-estradiol was studied while blood flow was measured with the use of /sup 125/I-iodoantipyrine, blood volume was measured with the use of /sup 99m/Tc-labeled red blood cells, and the receptor concentration by in vitro assay. The results demonstrate no correlation between blood flow and uptake of ligand, or between receptor concentration and uptake of ligand. No correlation existed between blood volume and uptake or /sup 18/F-estradiol, even though the blood volume varied by a factor of --20 in the tumors studied. The distribution of the fluorine-18 may depend upon metabolites of the ligand rather than the ligand itself. The authors have developed a technique to separate metabolites from the administered compound in blood and tissues. The distribution of the compound in the blood at times >30 mins after injection was primarily within the red blood cells in a chemical form that was not extractable even in lysed blood samples. By injecting blood from one rate into another the authors have shown that the activity in blood 2 hours after injection of /sup 18/F-estradiol is not available for uptake in receptor rich tissue but remains in the blood and non-target tissues

  6. The interstitial distribution of macromolecules in rat tumours is influenced by the negatively charged matrix components.

    Science.gov (United States)

    Wiig, Helge; Gyenge, Christina C; Tenstad, Olav

    2005-09-01

    Knowledge of macromolecular distribution volumes is essential in understanding fluid transport within normal and pathological tissues. In this study in vivo we determined the distribution volumes of several macromolecules, including one monoclonal antibody, in tumours and tested whether charges associated with the tumour extracellular matrix influence their available volumes. Steady state levels of the monoclonal antibody trastuzumab (Herceptin) (pI = 9.2), IgG (pI = 7.6) as well as native (pI = 5.0) and cationized albumin (pI = 7.6) were established in rats bearing dimethylbenzanthracene (DMBA)-induced mammary tumours by continuous infusion using osmotic minipumps. After a 5-7 day infusion period, the rats were nephrectomized and the extracellular volume was determined with 51Cr-labelled EDTA. Plasma volumes were measured with 125I-labelled human serum albumin or rat IgM in a separate series. Steady state concentrations of probes were determined in the interstitial fluid that was isolated by centrifugation from tumours or by post mortem wick implantation in the back skin. Calculations were made for interstitial fluid volume (Vi), along with the available (Va/Vi) and excluded (Ve/Vi) relative interstitial volume fractions. The Ve/Vi for the positively charged trastuzumab in tumours averaged 0.29 +/- 0.03 (n = 16), a value which was significantly lower than the corresponding one for IgG of 0.36 +/- 0.02 (n = 16). Native albumin was excluded from 38% of the tumour interstitial fluid, whereas cationization of albumin reduced the excluded volume by approximately 50%. Our experiments suggest that the tumour interstitium acts as a negatively charged matrix and is an important factor in determining the macromolecular distribution volume.

  7. Modulation of Signal Proteins: A Plausible Mechanism to Explain How a Potentized Drug Secale Cor 30C Diluted beyond Avogadro's Limit Combats Skin Papilloma in Mice.

    Science.gov (United States)

    Khuda-Bukhsh, Anisur Rahman; Bhattacharyya, Soumya Sundar; Paul, Saili; Dutta, Suman; Boujedaini, Naoual; Belon, Philippe

    2011-01-01

    In homeopathy, ability of ultra-high diluted drugs at or above potency 12C (diluted beyond Avogadro's limit) in ameliorating/curing various diseases is often questioned, particularly because the mechanism of action is not precisely known. We tested the hypothesis if suitable modulations of signal proteins could be one of the possible pathways of action of a highly diluted homeopathic drug, Secale cornutum 30C (diluted 10(60) times; Sec cor 30). It could successfully combat DMBA + croton oil-induced skin papilloma in mice as evidenced by histological, cytogenetical, immunofluorescence, ELISA and immunoblot findings. Critical analysis of several signal proteins like AhR, PCNA, Akt, Bcl-2, Bcl-xL, NF-κB and IL-6 and of pro-apoptotic proteins like cytochrome c, Bax, Bad, Apaf, caspase-3 and -9 revealed that Sec cor 30 suitably modulated their expression levels along with amelioration of skin papilloma. FACS data also suggested an increase of cell population at S and G2 phases and decrease in sub-G1 and G1 phages in carcinogen-treated drug-unfed mice, but these were found to be near normal in the Sec cor 30-fed mice. There was reduction in genotoxic and DNA damages in bone marrow cells of Sec Cor 30-fed mice, as revealed from cytogenetic and Comet assays. Changes in histological features of skin papilloma were noted. Immunofluorescence studies of AhR and PCNA also suggested reduced expression of these proteins in Sec cor 30-fed mice, thereby showing its anti-cancer potentials against skin papilloma. Furthermore, this study also supports the hypothesis that potentized homeopathic drugs act at gene regulatory level.

  8. Modulation of Signal Proteins: A Plausible Mechanism to Explain How a Potentized Drug Secale Cor 30C Diluted beyond Avogadro's Limit Combats Skin Papilloma in Mice

    Directory of Open Access Journals (Sweden)

    Anisur Rahman Khuda-Bukhsh

    2011-01-01

    Full Text Available In homeopathy, ability of ultra-high diluted drugs at or above potency 12C (diluted beyond Avogadro's limit in ameliorating/curing various diseases is often questioned, particularly because the mechanism of action is not precisely known. We tested the hypothesis if suitable modulations of signal proteins could be one of the possible pathways of action of a highly diluted homeopathic drug, Secale cornutum 30C (diluted 1060 times; Sec cor 30. It could successfully combat DMBA + croton oil-induced skin papilloma in mice as evidenced by histological, cytogenetical, immunofluorescence, ELISA and immunoblot findings. Critical analysis of several signal proteins like AhR, PCNA, Akt, Bcl-2, Bcl-xL, NF-κB and IL-6 and of pro-apoptotic proteins like cytochrome c, Bax, Bad, Apaf, caspase-3 and -9 revealed that Sec cor 30 suitably modulated their expression levels along with amelioration of skin papilloma. FACS data also suggested an increase of cell population at S and G2 phases and decrease in sub-G1 and G1 phages in carcinogen-treated drug-unfed mice, but these were found to be near normal in the Sec cor 30-fed mice. There was reduction in genotoxic and DNA damages in bone marrow cells of Sec Cor 30-fed mice, as revealed from cytogenetic and Comet assays. Changes in histological features of skin papilloma were noted. Immunofluorescence studies of AhR and PCNA also suggested reduced expression of these proteins in Sec cor 30-fed mice, thereby showing its anti-cancer potentials against skin papilloma. Furthermore, this study also supports the hypothesis that potentized homeopathic drugs act at gene regulatory level.

  9. Interstitial laser immunotherapy for treatment of metastatic mammary tumors in rats

    Science.gov (United States)

    Figueroa, Daniel; Joshi, Chet; Wolf, Roman F.; Walla, Jonny; Goddard, Jessica; Martin, Mallory; Kosanke, Stanley D.; Broach, Fred S.; Pontius, Sean; Brown, Destiny; Li, Xiaosong; Howard, Eric; Nordquist, Robert E.; Hode, Tomas; Chen, Wei R.

    2011-03-01

    Thermal therapy has been used for cancer treatment for more than a century. While thermal effect can be direct, immediate, and controllable, it is not sufficient to completely eradicate tumors, particularly when tumors have metastasized locally or to the distant sites. Metastases are the major cause of treatment failure and cancer deaths. Current available therapies, such as surgery, radiation, and chemotherapy, only have limited curative effects in patients with late-stage, metastatic cancers. Immunotherapy has been considered as the ultimate approach for cancer treatment since a systemic, anti-tumor, immunological response can be induced. Using the combination of photothermal therapy and immunotherapy, laser immunotherapy (LIT),a novel immunotherapy modality for late-stage cancer treatment, has been developed. LIT has shown great promise in pre-clinical studies and clinical breast cancer and melanoma pilot trials. However, the skin color and the depth of the tumor have been challenges for effective treatment with LIT. To induce a thermal destruction zone of appropriate size without causing thermal damage on the skin, we have developed interstitial laser immunotherapy (ILIT) using a cylindrical diffuser. To determine the effectiveness of ILIT, we treated the DMBA-4 metastatic tumors in rats. The thermal damage in tumor tissue was studied using TTC immersion and hematoxolin and eosin (H & E) staining. Also observed was the overall survival of the treated animals. Our results demonstrated that the ILIT could impact a much larger tumor area, and it significantly reduced the surface damage compared with the early version of non-invasive LIT. The survival data also indicate that ILIT has the potential to become an effective tool for the treatment of deeper, larger, and metastatic tumors, with reduced side effects.

  10. Detecção de lesões neoplásicas induzidas em mucosa oral de hamster utilizando espectroscopia de fluorescência Detection of induced neoplastic lesions in the oral mucosa of hamsters using fluorescence spectroscopy

    Directory of Open Access Journals (Sweden)

    Landulfo Silveira Junior

    2004-09-01

    Full Text Available OBJETIVO: Este trabalho teve por objetivo a utilização da técnica de espectroscopia de fluorescência induzida por laser para a caracterização de tecido normal e neoplásico em mucosa jugal de hamster, visando diagnosticar tecidos neoplásicos in vivo. MÉTODOS: O carcinógeno DMBA foi aplicado na bochecha direita de 31 hamsters com 150 ± 10g, três vezes por semana durante 12 semanas. Um animal foi mantido como controle (sem aplicação da droga. Após este período, os animais foram submetidos à espectroscopia de fluorescência induzida por laser de argônio (488nm, acoplado a um cabo de fibras ópticas. A autofluorescência do tecido foi guiada pelo cabo de fibras e analisada por um espectrógrafo e uma câmera CCD 1024X256 pixels, cobrindo a faixa espectral de 550nm a 700nm. Os espectros foram coletados na área da lesão induzida e na bochecha contralateral (normal de todos os animais, além do animal de controle. Subseqüente à espectroscopia, foi realizada a biópsia da lesão para a análise histopatológica. Dois algoritmos de diagnóstico dos espectros de tecido neoplásico, baseados na razão entre regiões espectrais e na técnica de análise das componentes principais (PCA foram implementados. RESULTADOS: Foi demonstrada a existência de um pico intenso na região de 630nm nos tecidos neoplásicos (atribuído à protoporfirina IX, quando comparados com o tecido normal. O algoritmo baseado na razão entre regiões espectrais obteve 100% de sensibilidade e especificidade. O algoritmo baseado na PCA obteve 94% e 100% de sensibilidade e especificidade, respectivamente. CONCLUSÕES: Este trabalho indica que a autofluorescência de tecidos da mucosa oral poderá ser utilizada como uma técnica não-invasiva de diagnóstico, com alta sensibilidade e especificidade.OBJECTIVE: This work analyzes use of the Laser Induced Fluorescence Spectroscopy technique for characterization of normal and neoplastic tissue in the oral mucosa of

  11. Hyperoxia increases the uptake of 5-fluorouracil in mammary tumors independently of changes in interstitial fluid pressure and tumor stroma

    Directory of Open Access Journals (Sweden)

    Salvesen Gerd S

    2009-12-01

    Full Text Available Abstract Background Hypoxia is associated with increased resistance to chemo- and radiation-therapy. Hyperoxic treatment (hyperbaric oxygen has previously been shown to potentiate the effect of some forms of chemotherapy, and this has been ascribed to enhanced cytotoxicity or neovascularisation. The aim of this study was to elucidate whether hyperoxia also enhances any actual uptake of 5FU (5-fluorouracil into the tumor tissue and if this can be explained by changes in the interstitium and extracellular matrix. Methods One group of tumor bearing rats was exposed to repeated hyperbaric oxygen (HBO treatment (2 bar, pO2 = 2 bar, 4 exposures à 90 min, whereas one group was exposed to one single identical HBO treatment. Animals housed under normal atmosphere (1 bar, pO2 = 0.2 bar served as controls. Three doses of 5FU were tested for dose response. Uptake of [3H]-5FU in the tumor was assessed, with special reference to factors that might have contributed, such as interstitial fluid pressure (Pif, collagen content, oxygen stress (measured as malondialdehyd levels, lymphatics and transcapillary transport in the tumors. Results The uptake of the cytostatic agent increases immediately after a single HBO treatment (more than 50%, but not 24 hours after the last repeated HBO treatment. Thus, the uptake is most likely related to the transient increase in oxygenation in the tumor tissue. Factors like tumor Pif and collagen content, which decreased significantly in the tumor interstitium after repeated HBO treatment, was without effect on the drug uptake. Conclusion We showed that hyperoxia increases the uptake of [3H]-5FU in DMBA-induced mammary tumors per se, independently of changes in Pif, oxygen stress, collagen fibril density, or transendothelial transport alone. The mechanism by which such an uptake occur is still not elucidated, but it is clearly stimulated by elevated pO2.

  12. The effect of fucoidan on intestinal flora and intestinal barrier function in rats with breast cancer.

    Science.gov (United States)

    Xue, Meilan; Ji, Xinqiang; Liang, Hui; Liu, Ying; Wang, Bing; Sun, Lingling; Li, Weiwei

    2018-02-21

    Recent research studies have shown that the intestinal flora are related to the occurrence and progress of breast cancer. This study investigates the effect of fucoidan on intestinal flora and intestinal barrier function in rats with 7,12-dimethylbenz[a]anthracene (DMBA)-induced breast cancers. Sixty female Sprague-Dawley rats were randomly assigned to the control group, the model group, and the F1 and F2 groups, which were fed fucoidan at concentrations of 200 and 400 mg per kg bw (body weight), respectively. Intestinal histopathological analysis was performed and 16S rDNA high-throughput sequencing was used to provide an overview of the intestinal flora composition. The contents of d-lactic acid (d-LA), diamine oxidase (DAO) and endotoxin in plasma were detected by ELISA. Expression levels of the tight junction (TJ) proteins, phosphorylated p38 MAPK and ERK1/2 were measured using western blotting. Our results suggested that the intestinal wall of the model group was damaged. However, after fucoidan intervention, the villi were gradually restored. ELISA showed that the levels of plasma endotoxin, d-LA and DAO decreased in the F1 and F2 groups compared to those in the model group. Fucoidan treatment also increased the expressions of ZO-1, occludin, claudin-1 and claudin-8. Furthermore, the expression levels of phosphorylated p38 MAPK and ERK1/2 were upregulated in fucoidan treatment groups. The results of 16S rDNA high-throughput sequencing indicated that fucoidan increased the diversity of the intestinal microbiota and induced changes in microbial composition, with the increased Bacteroidetes/Firmicutes phylum ratio. In conclusion, the supplement of fucoidan could improve the fecal microbiota composition and repair the intestinal barrier function. The study suggested the use of fucoidan as an intestinal flora modulator for potential prevention of breast cancer.

  13. Epidermal Rac1 regulates the DNA damage response and protects from UV-light-induced keratinocyte apoptosis and skin carcinogenesis

    Science.gov (United States)

    Deshmukh, Jayesh; Pofahl, Ruth; Haase, Ingo

    2017-01-01

    Non-melanoma skin cancer (NMSC) is the most common type of cancer. Increased expression and activity of Rac1, a small Rho GTPase, has been shown previously in NMSC and other human cancers; suggesting that Rac1 may function as an oncogene in skin. DMBA/TPA skin carcinogenesis studies in mice have shown that Rac1 is required for chemically induced skin papilloma formation. However, UVB radiation by the sun, which causes DNA damage, is the most relevant cause for NMSC. A potential role of Rac1 in UV-light-induced skin carcinogenesis has not been investigated so far. To investigate this, we irradiated mice with epidermal Rac1 deficiency (Rac1-EKO) and their controls using a well-established protocol for long-term UV-irradiation. Most of the Rac1-EKO mice developed severe skin erosions upon long-term UV-irradiation, unlike their controls. These skin erosions in Rac1-EKO mice healed subsequently. Surprisingly, we observed development of squamous cell carcinomas (SCCs) within the UV-irradiation fields. This shows that the presence of Rac1 in the epidermis protects from UV-light-induced skin carcinogenesis. Short-term UV-irradiation experiments revealed increased UV-light-induced apoptosis of Rac1-deficient epidermal keratinocytes in vitro as well as in vivo. Further investigations using cyclobutane pyrimidine dimer photolyase transgenic mice revealed that the observed increase in UV-light-induced keratinocyte apoptosis in Rac1-EKO mice is DNA damage dependent and correlates with caspase-8 activation. Furthermore, Rac1-deficient keratinocytes showed reduced levels of p53, γ-H2AX and p-Chk1 suggesting an attenuated DNA damage response upon UV-irradiation. Taken together, our data provide direct evidence for a protective role of Rac1 in UV-light-induced skin carcinogenesis and keratinocyte apoptosis probably through regulating mechanisms of the DNA damage response and repair pathways. PMID:28277539

  14. The Effect of Tamoxifen Administration and γ-Irradiation on Thyroid Hormones Levels in Rats Bearing Mammary Tumours

    International Nuclear Information System (INIS)

    Abdelgawad, M.R.

    2013-01-01

    Breast Cancer is the most common malignancy among women in most developed and developing regions of the world, in female, tamoxifen acting as an oestrogen antagonist on the breast. Thyroid hormones can stimulate the proliferation in vitro of certain tumor cell lines. The aim of the present study is to evaluate the effect of tamoxifen and/ or irradiation treatment on thyroid hormones in rats' mammary tumours. Forty-two female Sprague-Dawely rats randomly divided into seven groups' proliferation (6 rats each). Control group, normal rats supplemented with tamoxifen for 3 weeks, normal rats exposed to a single dose 3Gy γ-rays, rats treated with Dimethylbenz (a) anthracene (DMBA) dissolved in corn oil (30ppm) sc and followed for 6 months until breast cancer occurrence, breast cancer bearing rats supplemented with tamoxifen for 3 weeks twice a day, breast cancer bearing rats exposed to a single dose 3Gy γ-rays, breast cancer bearing rats exposed to a single dose 3Gy γ-rays and supplemented with tamoxifen for 3 weeks twice a day. At the end of the experiment, mammary tumours and control rats were sacrificed after 3 weeks from different treatments and serum thyroid hormones and estradiol (E2) levels were assayed using commercial kits. Results show T4 and E2 levels not triiodothyronine (T3) were altered in different experimental groups. It could be concluded that γ-irradiation promote the expression of neoplastic potential by affecting both E2 and thyroid hormones and tamoxifen may alter the thyroid hormones. Tamoxifen administration and γ-irradiation may have worth effects on thyroxin (T4) and E2 levels. It is recommended to further studies towards the bystander effect of γ-rays exposure and tamoxifen treatment on the tissue culture and molecular biology scale.

  15. Inhibitory effect of a formulated extract from multiple citrus peels on LPS-induced inflammation in RAW 246.7 macrophages

    Directory of Open Access Journals (Sweden)

    Tadahiro Etoh

    2013-06-01

    Full Text Available ABSTRACTBackground: Formulated Citrus Peel Extract (GL made from the peels of six citrus fruits available in Japan, namely navel oranges, citrus hassaku, citrus limon, citrus natsudaidai, citrus miyauchi and satsuma, was initially developed as a cosmetic product to protect skin from UV irradiation. Anecdotal evidences of anti-cancer property of GL have been reported by consumers based on the cases such as topical application for melanoma, and oral ingestion for prostate, lung and liver cancers.Those anecdotal reports stimulated us to investigate anti-tumorigenesis activity of GL. In the previous study, we reported that the topical application of GL inhibited DMBA/TPA-induced skin tumor formation by decreasing inflammatory gene parameters.Objective: In this study, we mainly investigated the effect of GL on translocation of NF-kB together with production of nitric-oxide and TNF-α induced by LPS in RAW 264.7 cells.Results: This investigation showed that GL decreased the release of TNF-α and nitric oxide from macrophage RAW264.7 cells stimulated by LPS in a dose-dependent manner. In addition, GL suppressed the expression of iNOS and nuclear translocation of NF-kB in RAW264.7 cells, inhibited the degradation of IκB-α, and scavenged hydroxyl radicals (DMPO/OH adduct in vitro.Conclusions: Our findings suggest that GL suppresses the inflammation in vitro, and exerts chemopreventive activity through the inhibition of production of TNF-α and iNOS proteins due to the inhibition of nuclear translocation of NF-kB and oxidative stress. GL appears to be a novel functional natural product capable of preventing inflammation and inflammation-associated tumorigenesis.Keywords: GL, Citrus peel extract, anti-inflammation, Nitric oxide, iNOS, NF-kB, TNF-α

  16. Inhibition of induced tumorigenesis by dietary 2-deoxy-D-Glucose in mice

    International Nuclear Information System (INIS)

    Singh, Saurabh; Pandey, Sanjay; Bhuria, Vikas; Bhatt, Anant Narayan; Taneja, Pankaj; Soni, Ravi; Dwarakanath, Bilikere S.; Oberoi, Raghav; Chawla, Aman Preet; Saluja, Daman

    2014-01-01

    Enhanced glycolysis facilitating proliferation and defence against death, besides energy production is a fundamental metabolic change exhibited by majority of the tumor types. Recent evidences support Warburg's proposition that this metabolic re-programming may also drive tumorigenesis induced by chemical carcinogens and radiation. Targeting this phenotype using the glycolytic inhibitor, 2-deoxy-D glucose (2-DG) has been shown to enhance the efficacy of radiation and chemotherapeutic drugs in experimental systems as well as clinics. 2-DG is also a potent Energy Restriction Mimetic Agent (ERMA) as an alternative to Dietary Energy Restriction (DER) for combating cancer. Since DER regimen is difficult to sustain in humans, we have hypothesized that 2-DG may impair the process of induced tumorigenesis, thereby offering an attractive chemopreventive strategy. Systematic studies have indeed shown that dietary 2-DG administration impairs the formation and growth of implanted tumor (Lewis Lung carcinoma; Ehrlich ascites carcinoma) as well as chemical (DMBA and TPA) and radiation-induced skin tumors in C57BL/6, Strain A and Swiss Albino mice respectively in the tumor implant study. Decrease in the fraction of animals bearing tumor and growth rate, besides increase in the latency period were evident. In the chemical and radiation induced tumor studies, a significant reduction in the percentage of tumor (papillomas) bearing animals (incidence), number of tumors per animal (tumor burden) and increased latency were observed. Although, mechanisms underlying cancer preventive/inhibitory potential of dietary 2-DG is not completely understood, our current findings suggests modifications of certain circulating factors (glucose and insulin), oxidative stress (LPO and GSH), immune status (CD4/CD8 and regulatory T-cells; T-regs), extracellular matrix (MMP-9) and angiogenesis (tumor associated and radiation-induced) as some of the contributing factors. Further studies are required

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

    Science.gov (United States)

    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.

  18. Can Phlorotannins Purified Extracts Constitute a Novel Pharmacological Alternative for Microbial Infections with Associated Inflammatory Conditions?

    Science.gov (United States)

    Lopes, Graciliana; Sousa, Carla; Silva, Luís R.; Pinto, Eugénia; Andrade, Paula B.; Bernardo, João; Mouga, Teresa; Valentão, Patrícia

    2012-01-01

    Bacterial and fungal infections and the emerging multidrug resistance are driving interest in fighting these microorganisms with natural products, which have generally been considered complementary to pharmacological therapies. Phlorotannins are polyphenols restricted to brown seaweeds, recognized for their biological capacity. This study represents the first research on the antibacterial, antifungal, anti-inflammatory and antioxidant activity of phlorotannins purified extracts, which were obtained from ten dominant brown seaweeds of the occidental Portuguese coast. Phlorotannins content was determined by the specific dimethoxybenzaldehyde (DMBA) method and a yield between 75 and 969 mg/Kg phloroglucinol units (dry matter) was obtained. Fucus spiralis ranked first, followed by three Cystoseira species. The anti-inflammatory potential of the purified extracts was assessed via inhibitory effect on nitric oxide (NO) production by lipopolysaccharide-stimulated RAW 264.7 macrophage cells, Cystoseira tamariscifolia being the one showing promising activity for the treatment of inflammation. NO scavenging ability was also addressed in cell free systems, F. spiralis being the species with highest capacity. The antimicrobial potential of the extracts was checked against five Gram-positive and four Gram-negative bacteria and three fungi strains, that commonly colonize skin and mucosa and are responsible for food contamination. The different extracts were more effective against Gram-positive bacteria, Staphylococcus epidermidis being the most susceptible species. Concerning antifungal activity, Trichophyton rubrum was the most sensitive species. Although the molecular mechanisms underlying these properties remain poorly understood, the results obtained turn phlorotannins purified extracts a novel and potent pharmacological alternative for the treatment of a wide range of microbial infections, which usually also present an inflammatory component. In addition to the biological

  19. Spontaneous transformation of murine oviductal epithelial cells: A model system to investigate the onset of fallopian-derived tumors

    Directory of Open Access Journals (Sweden)

    MIchael P. Endsley

    2015-07-01

    Full Text Available High-grade serous carcinoma (HGSC is the most lethal ovarian cancer histotype. The fallopian tube secretory epithelial cells (FTSECs are a proposed progenitor cell type. Genetically altered FTSECs form tumors in mice; however, a spontaneous HGSC model has not been described. Apart from a subpopulation of genetically predisposed women, most women develop ovarian cancer spontaneously, which is associated with aging and lifetime ovulations. A murine oviductal cell line (MOELOW was developed and continuously passaged in culture to mimic cellular aging (MOEHIGH. The MOEHIGH cellular model exhibited a loss of acetylated tubulin consistent with an outgrowth of secretory epithelial cells in culture. MOEHIGH cells proliferated significantly faster than MOELOW, and the MOEHIGH cells produced more 2D foci and 3D soft agar colonies as compared to MOELOW. MOEHIGH were xenografted into athymic female nude mice both in the subcutaneous and the intraperiteonal compartments. Only the subcutaneous grafts formed tumors that were negative for cytokeratin, but positive for oviductal markers such as oviductal glycoprotein 1 and Pax8. These tumors were considered to be poorly differentiated carcinoma. The differential molecular profiles between MOEHIGH and MOELOW were determined using RNA-Seq and confirmed by protein expression to uncover pathways important in transformation, like the p53 pathway, the FOXM1 pathway, WNT signaling, and splicing. MOEHIGH had enhanced protein expression of c-myc, Cyclin E, p53 and FOXM1 with reduced expression of p21. MOEHIGH were also less sensitive to cisplatin and DMBA, which induce lesions typically repaired by base-excision repair. A model of spontaneous tumorogenesis was generated starting with normal oviductal cells. Their transition to cancer involved alterations in pathways associated with high-grade serous cancer in humans.

  20. Epidermal Rac1 regulates the DNA damage response and protects from UV-light-induced keratinocyte apoptosis and skin carcinogenesis.

    Science.gov (United States)

    Deshmukh, Jayesh; Pofahl, Ruth; Haase, Ingo

    2017-03-09

    Non-melanoma skin cancer (NMSC) is the most common type of cancer. Increased expression and activity of Rac1, a small Rho GTPase, has been shown previously in NMSC and other human cancers; suggesting that Rac1 may function as an oncogene in skin. DMBA/TPA skin carcinogenesis studies in mice have shown that Rac1 is required for chemically induced skin papilloma formation. However, UVB radiation by the sun, which causes DNA damage, is the most relevant cause for NMSC. A potential role of Rac1 in UV-light-induced skin carcinogenesis has not been investigated so far. To investigate this, we irradiated mice with epidermal Rac1 deficiency (Rac1-EKO) and their controls using a well-established protocol for long-term UV-irradiation. Most of the Rac1-EKO mice developed severe skin erosions upon long-term UV-irradiation, unlike their controls. These skin erosions in Rac1-EKO mice healed subsequently. Surprisingly, we observed development of squamous cell carcinomas (SCCs) within the UV-irradiation fields. This shows that the presence of Rac1 in the epidermis protects from UV-light-induced skin carcinogenesis. Short-term UV-irradiation experiments revealed increased UV-light-induced apoptosis of Rac1-deficient epidermal keratinocytes in vitro as well as in vivo. Further investigations using cyclobutane pyrimidine dimer photolyase transgenic mice revealed that the observed increase in UV-light-induced keratinocyte apoptosis in Rac1-EKO mice is DNA damage dependent and correlates with caspase-8 activation. Furthermore, Rac1-deficient keratinocytes showed reduced levels of p53, γ-H2AX and p-Chk1 suggesting an attenuated DNA damage response upon UV-irradiation. Taken together, our data provide direct evidence for a protective role of Rac1 in UV-light-induced skin carcinogenesis and keratinocyte apoptosis probably through regulating mechanisms of the DNA damage response and repair pathways.

  1. Assessment of gut microbiota populations in lean and obese Zucker rats.

    Directory of Open Access Journals (Sweden)

    Reza Hakkak

    Full Text Available Obesity has been on the rise in the US and worldwide for the last several decades. Obesity has been associated with chronic disease development, such as certain types of cancer, type 2 diabetes, cardiovascular disease, and liver diseases. Previously, we reported that obesity promotes DMBA-induced mammary tumor development using the obese Zucker rat model. The intestinal microbiota is composed of a diverse population of obligate and facultative anaerobic microorganisms, and these organisms carry out a broad range of metabolic activities. Obesity has been linked to changes in the intestinal microbiota, but the composition of the bacterial populations in lean and obese Zucker rats has not been carefully studied. Therefore, the objective of this study was to determine the effects of obesity on the gut microbiota in this model. Lean and obese female Zucker rats (n = 16 were fed an AIN-93G-like diet for 8 weeks. Rats were weighed twice weekly, and fecal samples were collected at the beginning and end of the experiment. 16S rRNA gene sequencing was used to evaluate the composition of the fecal bacterial populations. At the outset of the study, the lean rats exhibited much lower ratios of the Firmicutes to Bacteroidetes phyla than the obese rats, but after 60 days, this ratio in the lean rats exceeded that of the obese. This shift was associated with reductions in the Bacteroidaceae, S24-7 and Paraprevotellaceae families in the lean rats. Obese rats also showed increased levels of the genus Akkermansia at day 60. PCoA plots of beta diversity showed clustering of the different test groups, indicating clear differences in intestinal microbiota populations associated with both the time point of the study and the lean or obese status in the Zucker rat model for obesity.

  2. The oncogenic potential of three different 7, 12-dimethylbenz (a)anthracene transformed C3H/10T1/2 cell clones at various passages and the importance of the mode of immunosuppression

    International Nuclear Information System (INIS)

    Saxholm, H.J.K.

    1979-01-01

    The oncogenic potential of C3H/10T1/2 cells which were transformed in vitro with 7,12-dimethylbenz(a)anthracene is reported. The ability of the cells to grow as malignant tumors in syngeneic immunosuppressed mice was used as parameter for oncogenic potential. Cells of types I, II and III were assayed at several dosage levels, i.e., 10 4 , 10 5 or 10 6 cells per inoculum, with or without immunosuppression by antithymocyte serum globulin fraction. The studies were performed in several strains of host animals, i.e., male and female syngeneic C3H mice supplied by the National Cancer Institute, C3H mice supplied by Charles River and nude, athymic female mice. Morphological transformation preceded oncological transformation, and type I cells could not be established as tumors. Type II and type III cells developed oncogenic potential only after several passages in culture. Oncogenic potential was pronounced in the type III cells, and less strongly expressed in type II cells. Also tested were different methods of immunosuppression of the animal against the expression of the oncogenic potential of DMBA transformed C3H/10T1/2 cells from type II and III clones. Immunosuppression by antithymocyte serum globulin fraction was an effective method of preparing the syngeneic host so that cells with a low oncogenic potential would grow as tumors, whereas total body irradiation was not effective. For cells with a high oncogenic potential both ways of immunosuppression were sufficient. Admixing lethally irradiated cells in the cell inoculum slightly enhanced the tumor development from cells with low oncogenic potential and such addition was clearly effective for cells with a higher oncogenic potential, both for the antibody-treated and for the irradiated series. The findings were reproducible. The study stresses the importance of immunosuppression by antithymocyte globulins for detecting in vitro transformed weakly oncogenic cells. (author)

  3. Four experimental stimulants found in sports and weight loss supplements: 2-amino-6-methylheptane (octodrine), 1,4-dimethylamylamine (1,4-DMAA), 1,3-dimethylamylamine (1,3-DMAA) and 1,3-dimethylbutylamine (1,3-DMBA).

    OpenAIRE

    Cohen, Pieter A; Travis, John C; Keizers, Peter H J; Deuster, Patricia; Venhuis, Bastiaan J

    2017-01-01

    The United States Food and Drug Administration banned the stimulant 1,3-dimethylamylamine (1,3-DMAA) from dietary supplements and warned consumers that the stimulant can pose cardiovascular risks ranging from high blood pressure to heart attacks.

  4. Deoxynivalenol induced mouse skin cell proliferation and inflammation via MAPK pathway

    International Nuclear Information System (INIS)

    Mishra, Sakshi; Tripathi, Anurag; Chaudhari, Bhushan P.; Dwivedi, Premendra D.; Pandey, Haushila P.; Das, Mukul

    2014-01-01

    Several toxicological manifestations of deoxynivalenol (DON), a mycotoxin, are well documented; however, dermal toxicity is not yet explored. The effect of topical application of DON to mice was studied using markers of skin proliferation, inflammation and tumor promotion. Single topical application of DON (84–672 nmol/mouse) significantly enhanced dermal hyperplasia and skin edema. DON (336 and 672 nmol) caused significant enhancement in [ 3 H]-thymidine uptake in DNA along with increased myeloperoxidase and ornithine decarboxylase activities, suggesting tissue inflammation and cell proliferation. Furthermore, DON (168 nmol) caused enhanced expression of RAS, and phosphorylation of PI3K/Akt, ERK, JNK and p38 MAPKs. DON exposure also showed activation of transcription factors, c-fos, c-jun and NF-κB along with phosphorylation of IkBα. Enhanced phosphorylation of NF-κB by DON caused over expression of target proteins, COX-2, cyclin D1 and iNOS in skin. Though a single topical application of DMBA followed by twice weekly application of DON (84 and 168 nmol) showed no tumorigenesis after 24 weeks, however, histopathological studies suggested hyperplasia of the epidermis and hypertrophy of hair follicles. Interestingly, intestine was also found to be affected as enlarged Peyer's patches were observed, suggesting inflammatory effects which were supported by elevation of inflammatory cytokines after 24 weeks of topical application of DON. These results suggest that DON induced cell proliferation in mouse skin is through the activation of MAPK signaling pathway involving transcription factors NFκB and AP-1, further leading to transcriptional activation of downstream target proteins c-fos, c-jun, cyclin D1, iNOS and COX-2 which might be responsible for its inflammatory potential. - Highlights: • Topical application of DON enhanced epidermal inflammation and cell proliferation. • DON follows PI3K/Akt/MAPK signaling cascade, with activation of AP-1 and NF

  5. Multiple susceptibility loci for radiation-induced mammary tumorigenesis in F2[Dahl S x R]-intercross rats.

    Directory of Open Access Journals (Sweden)

    Victoria L Herrera

    Full Text Available Although two major breast cancer susceptibility genes, BRCA1 and BRCA2, have been identified accounting for 20% of breast cancer genetic risk, identification of other susceptibility genes accounting for 80% risk remains a challenge due to the complex, multi-factorial nature of breast cancer. Complexity derives from multiple genetic determinants, permutations of gene-environment interactions, along with presumptive low-penetrance of breast cancer predisposing genes, and genetic heterogeneity of human populations. As with other complex diseases, dissection of genetic determinants in animal models provides key insight since genetic heterogeneity and environmental factors can be experimentally controlled, thus facilitating the detection of quantitative trait loci (QTL. We therefore, performed the first genome-wide scan for loci contributing to radiation-induced mammary tumorigenesis in female F2-(Dahl S x R-intercross rats. Tumorigenesis was measured as tumor burden index (TBI after induction of rat mammary tumors at forty days of age via ¹²⁷Cs-radiation. We observed a spectrum of tumor latency, size-progression, and pathology from poorly differentiated ductal adenocarcinoma to fibroadenoma, indicating major effects of gene-environment interactions. We identified two mammary tumorigenesis susceptibility quantitative trait loci (Mts-QTLs with significant linkage: Mts-1 on chromosome-9 (LOD-2.98 and Mts-2 on chromosome-1 (LOD-2.61, as well as two Mts-QTLs with suggestive linkage: Mts-3 on chromosome-5 (LOD-1.93 and Mts-4 on chromosome-18 (LOD-1.54. Interestingly, Chr9-Mts-1, Chr5-Mts-3 and Chr18-Mts-4 QTLs are unique to irradiation-induced mammary tumorigenesis, while Chr1-Mts-2 QTL overlaps with a mammary cancer susceptibility QTL (Mcs 3 reported for 7,12-dimethylbenz-[α]antracene (DMBA-induced mammary tumorigenesis in F2[COP x Wistar-Furth]-intercross rats. Altogether, our results suggest at least three distinct susceptibility QTLs for

  6. N-heterocycle carbene (NHC)-ligated cyclopalladated N,N-dimethylbenzylamine: a highly active, practical and versatile catalyst for the Heck-Mizoroki reaction.

    Science.gov (United States)

    Peh, Guang-Rong; Kantchev, Eric Assen B; Zhang, Chi; Ying, Jackie Y

    2009-05-21

    The wide dissemination of catalytic protocols in academic and industrial laboratories is facilitated by the development of catalysts that are not only highly active but also user-friendly, stable to moisture, air and long term storage and easy to prepare on a large scale. Herein we describe a protocol for the Heck-Mizoroki reaction mediated by cyclopalladated N,N-dimethylbenzylamine (dmba) ligated with a N-heterocyclic carbene, 1,3-bis(mesityl)imidazol-2-ylidene (IMes), that fulfils these criteria. The precatalyst can be synthesized on approximately 100 g scale by a tri-component, sequential, one-pot reaction of N,N-dimethylbenzylamine, PdCl2 and IMes.HCl in refluxing acetonitrile in air in the presence of K2CO3. This single component catalyst is stable to air, moisture and long term storage and can be conveniently dispensed as a stock solution in NMP. It mediates the Heck-Mizoroki reaction of a range of aryl- and heteroaryl bromides in reagent grade NMP at the 0.1-2 mol% range without the need for rigorous anhydrous techniques or a glovebox, and is active even in air. The catalyst is capable of achieving very high levels of catalytic activity (TON of up to 5.22 x 10(5)) for the coupling of a deactivated arylbromide, p-bromoanisole, with tBu acrylate as a benchmark substrate pair. A wide range of aryl bromides, iodides and, for the first time with a NHC-Pd catalyst, a triflate was coupled with diverse acrylate derivatives (nitrile, tert-butyl ester and amides) and styrene derivatives. The use of excess (>2 equiv.) of the aryl bromide and tert-butyl acrylate leads to mixture of tert-butyl beta,beta-diarylacrylate and tert-butyl cinnamate derivatives depending on the substitution pattern of the aryl bromide. Electron rich m- and p-substituted arylbromides give the diarylated products exclusively, whereas electron-poor aryl bromides give predominantly mono-arylated products. For o-substituted aryl bromides, no doubly arylated products could be obtained under any

  7. P-MAPA immunotherapy potentiates the effect of cisplatin on serous ovarian carcinoma through targeting TLR4 signaling.

    Science.gov (United States)

    de Almeida Chuffa, Luiz Gustavo; de Moura Ferreira, Grazielle; Lupi, Luiz Antonio; da Silva Nunes, Iseu; Fávaro, Wagner José

    2018-01-17

    Toll-like receptors (TLRs) are transmembrane proteins expressed on the surface of ovarian cancer (OC) and immune cells. Identifying the specific roles of the TLR-mediated signaling pathways in OC cells is important to guide new treatments. Because immunotherapies have emerged as the adjuvant treatment for patients with OC, we investigated the effect of a promising immunotherapeutic strategy based on protein aggregate magnesium-ammonium phospholinoleate-palmitoleate anhydride (P-MAPA) combined with cisplatin (CIS) on the TLR2 and TLR4 signaling pathways via myeloid differentiation factor 88 (MyD88) and TLR-associated activator of interferon (TRIF) in an in vivo model of OC. Tumors were chemically induced by a single injection of 100 μg of 7,12-dimethylbenz(a)anthracene (DMBA) directly under the left ovarian bursa in Fischer 344 rats. After the rats developed serous papillary OC, they were given P-MAPA, CIS or the combination P-MAPA+CIS as therapies. To understand the effects of the treatments, we assessed the tumor size, histopathology, and the TLR2- and TLR4-mediated inflammatory responses. Although CIS therapy was more effective than P-MAPA in reducing the tumor size, P-MAPA immunotherapy significantly increased the expressions of TLR2 and TLR4. More importantly, the combination of P-MAPA with CIS showed a greater survival rate compared to CIS alone, and exhibited a significant reduction in tumor volume compared to P-MAPA alone. The combination therapy also promoted the increase in the levels of the following OC-related proteins: TLR4, MyD88, TRIF, inhibitor of phosphorylated NF-kB alpha (p-IkBα), and nuclear factor kappa B (NF-kB p65) in both cytoplasmic and nuclear sites. While P-MAPA had no apparent effect on tumor necrosis factor alpha (TNF-α) and interleukin (IL)-6, it seems to increase interferon-γ (IFN-γ), which may induce the Thelper (Th1)-mediated immune response. Collectively, our results suggest that P-MAPA immunotherapy combined with cisplatin

  8. Mobile phone base stations-Effects on wellbeing and health.

    Science.gov (United States)

    Kundi, Michael; Hutter, Hans-Peter

    2009-08-01

    Studying effects of mobile phone base station signals on health have been discouraged by authoritative bodies like WHO International EMF Project and COST 281. WHO recommended studies around base stations in 2003 but again stated in 2006 that studies on cancer in relation to base station exposure are of low priority. As a result only few investigations of effects of base station exposure on health and wellbeing exist. Cross-sectional investigations of subjective health as a function of distance or measured field strength, despite differences in methods and robustness of study design, found indications for an effect of exposure that is likely independent of concerns and attributions. Experimental studies applying short-term exposure to base station signals gave various results, but there is weak evidence that UMTS and to a lesser degree GSM signals reduce wellbeing in persons that report to be sensitive to such exposures. Two ecological studies of cancer in the vicinity of base stations report both a strong increase of incidence within a radius of 350 and 400m respectively. Due to the limitations inherent in this design no firm conclusions can be drawn, but the results underline the urgent need for a comprehensive investigation of this issue. Animal and in vitro studies are inconclusive to date. An increased incidence of DMBA induced mammary tumors in rats at a SAR of 1.4W/kg in one experiment could not be replicated in a second trial. Indications of oxidative stress after low-level in vivo exposure of rats could not be supported by in vitro studies of human fibroblasts and glioblastoma cells. From available evidence it is impossible to delineate a threshold below which no effect occurs, however, given the fact that studies reporting low exposure were invariably negative it is suggested that power densities around 0.5-1mW/m(2) must be exceeded in order to observe an effect. The meager data base must be extended in the coming years. The difficulties of investigating

  9. Radioprotective agents to reduce BNCT (Boron Neutron Capture Therapy) induced mucositis in the hamster cheek pouch; Agentes radioprotectores para reducir la mucositis inducida por la terapia por captura neutrónica en boro (BNCT) en la bolsa de la mejilla del hámster

    Energy Technology Data Exchange (ETDEWEB)

    Monti Hughes, A. [Dpto. de Radiobiología, Gerencia de Química Nuclear y Ciencias de la Salud, GAATEN, Comisión Nacional de Energía Atómica (CNEA) (Argentina); Pozzi, E. C.C. [Gerencia de Reactores de Investigación y Producción, GAATEN, CNEA (Argentina); Thorp, S., E-mail: andrea.monti@cnea.gov.ar [Sub-Gerencia Instrumentación y Control, GAEN, CNEA(Argentina)

    2013-07-01

    Introduction: BNCT is based on the capture reaction between boron, selectively targeted to tumor tissue, and thermal neutrons which gives rise to lethal, short-range high linear energy transfer particles that selectively damage tumor tissue, sparing normal tissue. We previously evidenced a remarkable therapeutic success of BNCT mediated by boronophenylalanine (BPA) in the hamster cheek pouch oral cancer and pre cancer model. Despite therapeutic efficacy, mucositis induced in premalignant tissue was dose limiting and favored, in some cases, tumor development. In a clinical scenario, oral mucositis limits the dose administered to head and neck tumors. Aim: Our aim was to evaluate the effect of the administration of different radioprotective agents, seeking to reduce BNCT-induced mucositis to acceptable levels in dose-limiting premalignant tissue; without compromising therapeutic effect evaluated as inhibition on tumor development in premalignant tissue; without systemic or local side effects; and without negative effects on the biodistribution of the boron compound used for treatment. Materials and methods: Cancerized hamsters with DMBA (dimethylbenzanthracene) were treated with BPA-BNCT 5 Gy total absorbed dose to premalignant tissue, at the RA-3 Nuclear Reactor, divided into different groups: 1-treated with FLUNIXIN; 2- ATORVASTATIN; 3-THALIDOMIDE; 4-HISTAMINE (two concentrations: Low -1 mg/ml- and High -5 mg/ml-); 5-JNJ7777120; 6-JNJ10191584; 7-SALINE (vehicle). Cancerized animals without any treatment (neither BNCT nor radioprotective therapy) were also analyzed. We followed the animals during one month and evaluated the percentage of animals with unacceptable/severe mucositis, clinical status and percentage of animals with new tumors post treatment. We also performed a preliminary biodistribution study of BPA + Histamine “low” concentration to evaluate the potential effect of the radioprotector on BPA biodistribution. Results: Histamine

  10. Radioprotective agents to reduce BNCT (Boron Neutron Capture Therapy) induced mucositis in the hamster cheek pouch

    International Nuclear Information System (INIS)

    Monti Hughes, A.; Pozzi, E.C.C.; Thorp, S.

    2013-01-01

    Introduction: BNCT is based on the capture reaction between boron, selectively targeted to tumor tissue, and thermal neutrons which gives rise to lethal, short-range high linear energy transfer particles that selectively damage tumor tissue, sparing normal tissue. We previously evidenced a remarkable therapeutic success of BNCT mediated by boronophenylalanine (BPA) in the hamster cheek pouch oral cancer and pre cancer model. Despite therapeutic efficacy, mucositis induced in premalignant tissue was dose limiting and favored, in some cases, tumor development. In a clinical scenario, oral mucositis limits the dose administered to head and neck tumors. Aim: Our aim was to evaluate the effect of the administration of different radioprotective agents, seeking to reduce BNCT-induced mucositis to acceptable levels in dose-limiting premalignant tissue; without compromising therapeutic effect evaluated as inhibition on tumor development in premalignant tissue; without systemic or local side effects; and without negative effects on the biodistribution of the boron compound used for treatment. Materials and methods: Cancerized hamsters with DMBA (dimethylbenzanthracene) were treated with BPA-BNCT 5 Gy total absorbed dose to premalignant tissue, at the RA-3 Nuclear Reactor, divided into different groups: 1-treated with FLUNIXIN; 2- ATORVASTATIN; 3-THALIDOMIDE; 4-HISTAMINE (two concentrations: Low -1 mg/ml- and High -5 mg/ml-); 5-JNJ7777120; 6-JNJ10191584; 7-SALINE (vehicle). Cancerized animals without any treatment (neither BNCT nor radioprotective therapy) were also analyzed. We followed the animals during one month and evaluated the percentage of animals with unacceptable/severe mucositis, clinical status and percentage of animals with new tumors post treatment. We also performed a preliminary biodistribution study of BPA + Histamine “low” concentration to evaluate the potential effect of the radioprotector on BPA biodistribution. Results: Histamine

  11. The non-protein coding breast cancer susceptibility locus Mcs5a acts in a non-mammary cell-autonomous fashion through the immune system and modulates T-cell homeostasis and functions.

    Science.gov (United States)

    Smits, Bart M G; Sharma, Deepak; Samuelson, David J; Woditschka, Stephan; Mau, Bob; Haag, Jill D; Gould, Michael N

    2011-08-16

    Mechanisms underlying low-penetrance, common, non-protein coding variants in breast cancer risk loci are largely undefined. We showed previously that the non-protein coding mammary carcinoma susceptibility locus Mcs5a/MCS5A modulates breast cancer risk in rats and women. The Mcs5a allele from the Wistar-Kyoto (WKy) rat strain consists of two genetically interacting elements that have to be present on the same chromosome to confer mammary carcinoma resistance. We also found that the two interacting elements of the resistant allele are required for the downregulation of transcript levels of the Fbxo10 gene specifically in T-cells. Here we describe mechanisms through which Mcs5a may reduce mammary carcinoma susceptibility. We performed mammary carcinoma multiplicity studies with three mammary carcinoma-inducing treatments, namely 7,12-dimethylbenz(a)anthracene (DMBA) and N-nitroso-N-methylurea (NMU) carcinogenesis, and mammary ductal infusion of retrovirus expressing the activated HER2/neu oncogene. We used mammary gland and bone marrow transplantation assays to assess the target tissue of Mcs5a activity. We used immunophenotyping assays on well-defined congenic rat lines carrying susceptible and resistant Mcs5a alleles to identify changes in T-cell homeostasis and function associated with resistance. We show that Mcs5a acts beyond the initial step of mammary epithelial cell transformation, during early cancer progression. We show that Mcs5a controls susceptibility in a non-mammary cell-autonomous manner through the immune system. The resistant Mcs5a allele was found to be associated with an overabundance of gd T-cell receptor (TCR)+ T-cells as well as a CD62L (L-selectin)-high population of all T-cell classes. In contrast to in mammary carcinoma, gdTCR+ T-cells are the predominant T-cell type in the mammary gland and were found to be overabundant in the mammary epithelium of Mcs5a resistant congenic rats. Most of them simultaneously expressed the CD4, CD8, and CD161