Maternal Western Style Diet Increases Susceptibility to Chemically-Induced Mammary Carcinogenesis in Female Rats Offspring

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Evaluation of Carcinogenic Potential of Diuron in a Rat Mammary Two-Stage Carcinogenesis Model

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Chemopreventive effects of mate against mouse mammary and colon carcinogenesis

The present study evaluated the chemopreventive potential of mate tea-like intake on mammary and colon carcinogenesis initiated by 7,12-dimethylbenz(a)antracene (DMBA) and 1,2-dimethylhydrazine (DMH) in female Swiss mice. After the initiation period, the animals received basal diet and organic mate tea-like, conventional mate tea-like, or green tea (positive control) at 2.0% as the drinking fluid during 15 weeks. At week 20, colon and mammary gland were analyzed for preneoplastic and neoplastic lesions development. Colon and mammary gland complexes were processed for cell proliferation analysis, estimated by proliferating cell nuclear antigen labeling index (PCNA-LI%). Specially, organic mate tea-like reduced the values of PCNA-LI% in colonic crypts (p < .003) and in mammary glands (p < .05) in DMBA/DMH-initiated groups. A lower incidence of aberrant crypt foci (ACF) in colon (p = .03) and of hyperplastic and neoplastic lesions in mammary gland (p < .05 and p < .02, respectively) was observed in DMBA/DMH-initiated groups treated with organic mate tea-like. These results suggest that post-initiation treatment with organic mate tea-like inhibited the development of colon and mammary carcinogenesis in a two-step medium-term mouse carcinogenesis model.

Protective effects of lemongrass (Cymbopogon citratus STAPF) essential oil on DNA damage and carcinogenesis in female Balb/C mice

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of Ginkgo biloba on chemically-induced mammary tumors in rats receiving tamoxifen

Background: Ginkgo biloba extract (GbE) is used extensively by breast cancer patients undergoing treatment with Tamoxifen (TAM). Thus, the present study investigated the effects of GbE in female Sprague-Dawley (SD) rats bearing chemically-induced mammary tumors and receiving TAM.Methods: Animals bearing mammary tumors (≥1 cm in diameter) were divided into four groups: TAM [10 mg/kg, intragastrically (i.g.)], TAM plus GbE [50 and 100 mg/kg, intraperitoneally (i.p.)] or an untreated control group. After 4 weeks, the therapeutic efficacy of the different treatments was evaluated by measuring the tumor volume (cm3) and the proportions of each tumor that were alive, necrotic or degenerative (mm2). In addition, labeling indexes (LI%) were calculated for cell proliferation (PCNA LI%) and apoptosis (cleaved caspase-3 LI%), expression of estrogen receptor-alpha (ER-α) and p63 biomarkers.Results: Overall, the tumor volume and the PCNA LI% within live tumor areas were reduced by 83% and 99%, respectively, in all TAM-treated groups when compared to the untreated control group. GbE treatment (100 mg/kg) reduced the proportions of live (24.8%) and necrotic areas (2.9%) (p = 0.046 and p = 0.038, respectively) and significantly increased the proportion of degenerative areas (72.9%) (p = 0.004) in mammary tumors when compared to the group treated only with TAM. The expression of ER-α, p63 and cleaved caspase-3 in live tumor tissues was not modified by GbE treatment.Conclusions: Co-treatment with 100 mg/kg GbE presented a slightly beneficial effect on the therapeutic efficacy of TAM in female SD rats bearing mammary tumors. © 2013 Dias et al.; licensee BioMed Central Ltd.

CDHI promoter hypermethylation and E-cadherin protein expression in infiltrating breast cancer

Background: the E-cadherin gene (CDH1) maps, at chromosome 16q22.1, a region often associated with loss of heterozygosity (LOH) in human breast cancer. LOH at this site is thought to lead to loss of function of this tumor suppressor gene and was correlated with decreased disease-free survival, poor prognosis, and metastasis. Differential CpG island methylation in the promoter region of the CDH1 gene might be an alternative way for the loss of expression and function of E-cadherin, leading to loss of tissue integrity, an essential step in tumor progression.Methods: the aim of our study was to assess, by Methylation-Specific Polymerase Chain Reaction (MSP), the methylation pattern of the CDH1 gene and its possible correlation with the expression of E-cadherin and other standard immunohistochemical parameters (Her-2, ER, PgR, p53, and K-67) in a series of 79 primary breast cancers ( 71 infiltrating ductal, 5 infiltrating lobular, 1 metaplastic, 1 apocrine, and 1 papillary carcinoma).Results: CDH1 hypermethylation was observed in 72% of the cases including 52/71 ductal, 4/5 lobular carcinomas and 1 apocrine carcinoma. Reduced levels of E-cadherin protein were observed in 85% of our samples. Although not statistically significant, the levels of E-cadherin expression tended to diminish with the CDH1 promoter region methylation. In the group of 71 ductal cancinomas, most of the cases of showing CDH1 hypermethylation also presented reduced levels of expression of ER and PgR proteins, and a possible association was observed between CDH1 methylation and ER expression ( p = 0.0301, Fisher's exact test). However, this finding was not considered significant after Bonferroni correction of p-value.Conclusion: Our preliminary findings suggested that abnormal CDH1 methylation occurs in high frequencies in infiltrating breast cancers associated with a decrease in E-cadherin expression in a subgroup of cases characterized by loss of expression of other important genes to the mammary carcinogenesis process, probably due to the disruption of the mechanism of maintenance of DNA methylation in tumoral cells.

Assessment of Female Reproductive Endpoints in Sprague-Dawley Rats Developmentally Exposed to Diuron: Potential Ovary Toxicity

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeitos do treinamento aeróbio na hepatocarcinogênese química em ratos Wistar alimentados com dieta basal ou hiperlipídica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise mutacional da região dos exons 5 a 8 do gene supressor de tumor p53 em neoplasias mamárias caninas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da expressão dos genes TGFBR1 e TGFBR2 em amostras de carcinomas ductais invasivos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeitos das dietas em Ômega-3 OU Ômega-6 na expressão gênica de neoplasias mamárias de ratas Sprague-Dawley sob o tratamento com tomoxifeno

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Carcinogênese de mama em modelo experimental de exposição gestacional, juvenil e adulta ao herbicida Diuron [3(3,4-Diclorofenil)1,1, Dimetil uréia] em fêmeas Sprague-Dawley

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Ação extra-nuclear do hormônio triiodotironina (T3) na expressão gênica de HIF-1α e TGFα em linhagem celular de adenocarcinoma mamário

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos da exposição gestacional, lactacional e juvenil às dietas com deficiência e suplementação de zinco e suscetibilidade a carcinogênese da mama em fêmeas Sprague-Dawley

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Modulação da atividade das interleucinas 17B e 25 associadas à melatonina como indutores de apoptose em cultivo celular de neoplasias mamárias

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)