Fatores biológicos e ambientais envolvidos na etiopatogenia do câncer de mama

• Autor(a) principal: Stur, Elaine
• Data de Publicação: 2017
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/7143
• topic: Breast cancer; Mammary density; Breast lesions; Glyphosate; Aminomethylphosphonic acid; Roundup®; Câncer de mama; Densidade mamária; Lesões de mama; Glifosato; Ácido aminometilfosfônico; Biotecnologia; 61

The breast cancer has the biggest incidence and mortality in the worldwide female population among others cancers, currently being the main cause of deaths among women. It is a heterogeneous disease with many risk factors, such as age, ethnicity, genetics, obesity, menarche, menopause, reproductive factors and mammary density. Due to the strong influence of mammary density as a risk factor, the first part of this thesis, were realized an epidemiological study using mammography data was conducted with 11,826 women by the Diagnostic Image Center-Woman- Vitoria in Espirito Santo, Brazil. The main results revealed that advanced age, menopause, high number of children, and especially, higher body mass index are associated with low mammary densities. The advanced age was associated with low risk to breast lesions, while previous surgery, high body mass index and high mammary density were associated with presence of lesions. Factors that influence on the hormonal regulation in the body may help in the development of breast cancer. The second part of this paper deals with the relationship between herbicide use and cancer. Studies have reported that with the increase of herbicide use in most recent years, specifically glyphosate, the worldwide most utilized herbicide, may act as endocrine disruptor and mitogen, leading to changes on the tumor growth ratio. Thus, this study evaluated how the Roundup® (composed by a complexed form of glyphosate) and aminomethylphosphonic acid (mainly metabolic of glyphosate) acts on the gene expression of breast cancer cell lines dependent-hormone (MCF-7) and independent-hormone (MDA-MB-468). The results showed that the glyphosate led to a deregulation of at least 11 canonical pathways in both cell lines, which are mainly responsible for cell cycle and DNA damage repair. Besides that, the cell line MDA-MB-468 showed many changes on the metabolic process pathways. The aminomethylphosphonic acid led to fewer changes, nonetheless these indicated changes on the cellular metabolism. Such findings showed that, in a dose-dependent manner, Roundup® lead to changes on the cell proliferation, increasing the risk for the breast disease development. This study concludes that many risk factors can influence on the development and progression of breast lesions, acting in a dependent or independent manner, and also that the use of herbicides can influence in basic cellular functions, deregulating the homeostasis.