RESUMO
Zinc is required for fetal development and is involved in key processes associated with breast carcinogenesis. We evaluated whether maternal zinc deficiency or supplementation during gestation influences female offspring susceptibility to breast cancer in adulthood. C57BL/6 mice consumed during gestation control (30â¯p.p.m. zinc), zinc-deficient (8 p.p.m) or zinc-supplemented (45â¯p.p.m.) diets. Maternal zinc supplementation increased in female mice offspring the incidence of chemically-induced mammary adenocarcinomas that were heavier, compared to control group. This was accompanied by a decreased number of terminal end buds, increased cell proliferation and apoptosis, and increased tumor suppressors p21, p53 and Rassf1, Zfp382 and Stat3 expression in mammary glands, as well as increased zinc status. Although maternal zinc deficiency did not alter the incidence of these lesions, it also induced heavier mammary adenocarcinomas, compared to control group. These effects were accompanied by a decreased number of terminal end buds, increased proto-oncogenes c-Myc and Lmo4 expression and H3K9Me3 and H4K20Me3 epigenetic marks in mammary glands of offspring, and decreased zinc status and increased levels of oxidative marker malondialdehyde. The data suggest that both maternal zinc deficiency and supplementation during gestation programmed increased breast cancer susceptibility in adult mice offspring following a J-shaped pattern through distinct mechanisms.
Assuntos
Deficiências Nutricionais/complicações , Suplementos Nutricionais , Neoplasias Mamárias Experimentais/etiologia , Zinco/administração & dosagem , Zinco/deficiência , Animais , Apoptose , Proliferação de Células , Feminino , Perfilação da Expressão Gênica , Masculino , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proto-Oncogenes , Proteína Supressora de Tumor p53/metabolismoRESUMO
MicroRNAs (miRNAs) are post-transcriptional gene expression regulators which expression is frequently altered in hepatocellular carcinoma (HCC). ß-ionone (ßI) is noted for its ability to inhibit persistent preneoplastic lesions (pPNLs) in liver rats. We evaluated the expression of miRNAs involved in carcinogenesis and possible targets modulated by ßI, in pPNLs and surrounding of microdissected tissues. Rats subjected to resistant hepatocyte model were treated during promotion stage with ßI (16 mg/100 g body weight) or corn oil (CO; 0.25 mL/100 g body weight; controls). Five animals receive no treatment (NT). In CO group, 38 and 29 miRNAs showed reduced expression relative to NT (P < 0.05) in pPNLs and surrounding, respectively. No miRNAs showed increased expression in surrounding of the CO compared to NT group; however, 30 miRNAs showed increased expression (P ≤ 0.05) in pPNLs of the CO group. There was no difference between ßI and CO groups (P > 0.05) in the expression of miRNAs in surrounding. In pPNLs ßI increased expression of miR-122 and miR-34a (P ≤ 0.05) and reduced of Igf2 (P ≤ 0.05), target of the latter, compared to CO. Additionally, ßI decreased the expression of miR-181c and its target Gdf2 (P ≤ 0.05). ßI reduced the expression of miR-181b and miR-708 (P ≤ 0.05) and increased the expression of their respective target mRNAs Timp3 and Mtss1 (P ≤ 0.05), relative to CO group. Modulation of miRNAs target genes by ßI was confirmed in vitro. ßI is a promising chemopreventive agent in the initial stages of hepatocarcinogenesis, as it modulates the expression of the miRNAs and target genes that can alter the metastatic phenotype of HCC. © 2016 Wiley Periodicals, Inc.
Assuntos
Anticarcinógenos/uso terapêutico , Carcinoma Hepatocelular/prevenção & controle , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Hepáticas/prevenção & controle , Fígado/efeitos dos fármacos , MicroRNAs/genética , Norisoprenoides/uso terapêutico , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/metabolismo , Carcinogênese/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Humanos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/prevenção & controle , Ratos , Ratos WistarRESUMO
BACKGROUND: Although males contribute half of the embryo's genome, only recently has interest begun to be directed toward the potential impact of paternal experiences on the health of offspring. While there is evidence that paternal malnutrition may increase offspring susceptibility to metabolic diseases, the influence of paternal factors on a daughter's breast cancer risk has been examined in few studies. METHODS: Male Sprague-Dawley rats were fed, before and during puberty, either a lard-based (high in saturated fats) or a corn oil-based (high in n-6 polyunsaturated fats) high-fat diet (60 % of fat-derived energy). Control animals were fed an AIN-93G control diet (16 % of fat-derived energy). Their 50-day-old female offspring fed only a commercial diet were subjected to the classical model of mammary carcinogenesis based on 7,12-dimethylbenz[a]anthracene initiation, and mammary tumor development was evaluated. Sperm cells and mammary gland tissue were subjected to cellular and molecular analysis. RESULTS: Compared with female offspring of control diet-fed male rats, offspring of lard-fed male rats did not differ in tumor latency, growth, or multiplicity. However, female offspring of lard-fed male rats had increased elongation of the mammary epithelial tree, number of terminal end buds, and tumor incidence compared with both female offspring of control diet-fed and corn oil-fed male rats. Compared with female offspring of control diet-fed male rats, female offspring of corn oil-fed male rats showed decreased tumor growth but no difference regarding tumor incidence, latency, or multiplicity. Additionally, female offspring of corn oil-fed male rats had longer tumor latency as well as decreased tumor growth and multiplicity compared with female offspring of lard-fed male rats. Paternal consumption of animal- or plant-based high-fat diets elicited opposing effects, with lard rich in saturated fatty acids increasing breast cancer risk in offspring and corn oil rich in n-6 polyunsaturated fatty acids decreasing it. These effects could be linked to alterations in microRNA expression in fathers' sperm and their daughters' mammary glands, and to modifications in breast cancer-related protein expression in this tissue. CONCLUSIONS: Our findings highlight the importance of paternal nutrition in affecting future generations' risk of developing breast cancer.
Assuntos
Neoplasias da Mama/etiologia , Exposição Paterna , Efeitos Tardios da Exposição Pré-Natal , Animais , Apoptose , Neoplasias da Mama/patologia , Proliferação de Células , Transformação Celular Neoplásica , Análise por Conglomerados , Dieta Hiperlipídica , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Humanos , Lipídeos/química , Masculino , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Animais , Neoplasias Mamárias Experimentais , Carne , MicroRNAs , Plantas/química , Gravidez , Proteômica/métodos , Ratos , Espermatozoides/metabolismoRESUMO
Fatores dietéticos como o selênio (Se) são apontados como importantes moduladores do risco de desenvolvimento do câncer de mama. Essa neoplasia pode apresentar sua origem no início do desenvolvimento e, assim, a alimentação materna poderia ter importantes repercussões na programação fetal da doença. A fim de verificar se diferentes concentração de selênio na dieta materna poderiam programar o risco da progênie feminina ao câncer de mama, ratas foram alimentadas com ração contendo 0,15 (CO), 1,0 (SUP) ou 0,05 (DEF) ppm de Se durante a gestação e sua progênie feminina iniciada com DMBA. A progênie do grupo SUP apresentou menor suscetibilidade à carcinogênese, indicado pelo menor número médio e multiplicidade de adenocarcinomas mamários (p< 0,05), enquanto a do grupo DEF apresentou maior suscetibilidade à carcinogênese, indicado pela maior incidência dos mesmos (p< 0,05). Mães do grupo DEF apresentaram menor concentração de Se no sangue (p< 0,05) e sua prole apresentou menor atividade da enzima GPx1 (p< 0,05). Além disso, observou-se na glândula mamária da progênie de 50 dias menor expressão (western blot e qPCR) de ERα, Her-2, EGFR e Ras no grupo SUP em comparação aos grupos CO e DEF (p< 0,05). Analisou-se, ainda, o padrão de metilação global do DNA (HPLC-DAD), expressão das enzimas DNMT1, 3a e 3b (qPCR), o padrão global de modificações pós traducionais em histonas (western blot) e o padrão de metilação da região promotora do gene Erα (modificação com bissulfito e pirossequenciamento) na glândula mamária da progênie de 50 dias. Não houve diferença no padrão de metilação global do DNA e expressão das enzimas DNMTs (p>0,05). Houve aumento na expressão de H4K16 acetilada nos grupos SUP e DEF (p< 0,05). Finalmente, em comparação a progênie do grupo DEF, a do grupo SUP apresentou região promotora de Erα com aumento marginal (p=0,07) na metilação de dois dinucleotídeos CpG. Conclui-se que o consumo de diferentes concentrações de Se na dieta materna tem impacto sobre a suscetibilidade da progênie ao câncer de mama na vida adulta através da modulação da expressão de receptores e oncogenes relacionados ao desenvolvimeto dessa neoplasia, além da influência em processos epigenéticos. Tais resultados apontam para a existência de uma "janela de programação" no início do desenvolvimento sensível a ação do Se, resultando em diminuição do risco de câncer de mama quando suplementado na dieta materna e o inverso quando de sua deficiencia
Based on epidemiological studies and animal models, the essential micronutrient selenium has been highlighted as a promising dietary factor associated to breast cancer risk reduction. Breast cancer may have its origin in early development and thus the maternal diet could have important implications in the fetal programming of the disease. In order to ascertain whether differences in selenium concentration in maternal diet could modulate the susceptibility of female offspring to breast cancer, a biological assay was conducted in which female rats were fed a diet with 0.15 (CO), 1.0 (SUP) or 0.05 (DEF) ppm of selenium during gestational period and the female offspring subjected to a mammary carcinogenesis model induced by DMBA. SUP group offspring presented decreased susceptibility to mammary carcinogenesis, as indicated by lower (p< 0,05) average number and multiplicity od adenocarcinomas, while the DEF group offspring had a greater susceptibility, as indicated by the increase (p< 0,05) in adenocarcinomas incidency. Mothers of the DEF group pesented lower (p< 0,05) Se blood concetrations and their offspring presented lower (p<0,05).GPx1 activity. In addition, there was a decrease (p< 0,05) in ERα, Her-2, EGFR and Ras expression (western blot and qPCR) in the mammary gland of 7 weeks old female SUP group offspring when compared to CO and DEF groups offspring. DNA global methylation pattern (HPLC-DAD), DNMT1, 3a e 3b expression (qPCR), global pattern of post-translational modification in histones (western blot) and methylation status of Erα promoter region (bisulfite modification and pyrosequencing) were also evaluated in the mammary gland of 7 weeks old offspring. There was no diffrence (p>0,05) in DNA global methylation pattern and DNMTs expression. There was an increase in acetilated H4K16 expression in groups SUP and DEF (p< 0,05). Lastly, when compared to DEF offspring, the SUP offspring presented a marginal increase in the methylation of two CpG dinucleotides in the Erα promoter region. In conclusion, the consumption of different selenium concentration in maternal diet plays a role in the progeny's breast cancer susceptibility through the modulation of receptors and oncogenes expression, in addition to modifications in epigenetic patterns. These results indicate the presence of a "programming window" in the beggining of development susceptible to selenium effects, resulting in decreased breast cancer risk when supplemented and the opposite when deficient