Repercussions of melatonin on the risk of breast cancer: a systematic review and meta-analysis.

Breast Cancer is common in women, but its etiology is not yet fully understood. Several factors may contribute to its genesis, such as genetics, lifestyle, and the environment. Melatonin may be involved in the process of breast cancer. Therefore, the aim of this study is to evaluate the influence of the levels of melatonin on breast cancer through a systematic review and meta-analysis. We performed a systematic review according to PRISMA recommendations. The primary databases MEDLINE, Embase, and Cochrane were consulted. There was no restriction on the year of publication and language. Data of systematic reviews from April 2017 to September to 2017 were analyzed. The meta-analysis was conducted using RevMan 5.3 software provided by the Cochrane Collaboration. From a total of 570 articles, 9 manuscripts were included in this review. They analy onzed women with breast cancer and control patients, of which 10% and 90% were in the reproductive period and after menopause, respectively. The lowest level of melatonin was found in approximately 55% of studies with breast cancer in post-menopause. The metanalyses of the studies demonstrated low levels of melatonin in breast cancer patients (n=963) compared with control patients (n= 1332), with a mean difference between the studies of -3.54 (CI -6.01, -1.06). Another difference found was in the comparison between smoking patients, with an average difference between 1.80 [0.97-2.63]. Our data suggest that low levels of melatonin might be a risk factor for breast cancer.

An essay on individual self-determination / Um ensaio sobre a autodeterminação individual

There are several understandings about the role of human gender identity in the scientific field, this discussion correlates definitions of both social and biological basis. The current confusion in the conceptualization of "sex" and "gender" demonstrates the need for a comparative analysis of the scientific dynamic vocabulary, as well as the insertion of an interdisciplinary historical, social and cultural point of view together with the biological view outside the normative binary logic. The word "gender" can be defined as the social construction of sex, differing from the variable "sex" because it refers to a biological dimension of the anatomo-physiological characterization of humans, recognized as essential and innate in determining the distinctions between male and female. Therefore, the JHGD presents a thematic diversity that focuses on issues related to public health, demonstrating the need to develop knowledge and generate impact on public policy strategies, aiming at universality, equity and comprehensiveness in scientific research involving sex and gender and their impacts on health sciences.

Existem diversas compreensões acerca do papel da identidade de gênero do ser humano no espaço científico, essa discussão correlaciona definições tanto de base social quanto biológica. A atual confusão na conceptualização de "sexo" e "gênero" demonstra a necessidade de uma análise comparativa do vocabulário dinâmico científico, assim como, a inserção de um ponto de vista histórico, social e cultural interdisciplinares em conjunto com a visão biológica fora de uma lógica binária normativa. O vocábulo "gênero" pode ser definido como a construção social do sexo, diferenciando-se da variável "sexo" porque esta se refere a uma dimensão biológica da caracterização anatomo-fisiológica dos seres humanos, reconhecida como essencial e inata na determinação das distinções entre macho e fêmea. Por isto, o JHGD apresenta uma diversidade temática que tem como foco questões voltadas à saúde pública demonstrando a necessidade do desenvolvimento de conhecimento para gerar impacto nas estratégias de políticas públicas, visando a universalidade, equidade e a integralidade nas pesquisas científicas que envolvem sexo e gênero, e seus impactos nas ciências da saúde.

Repercussions of melatonin on the risk of breast cancer: a systematic review and meta-analysis

SUMMARY Breast Cancer is common in women, but its etiology is not yet fully understood. Several factors may contribute to its genesis, such as genetics, lifestyle, and the environment. Melatonin may be involved in the process of breast cancer. Therefore, the aim of this study is to evaluate the influence of the levels of melatonin on breast cancer through a systematic review and meta-analysis. We performed a systematic review according to PRISMA recommendations. The primary databases MEDLINE, Embase, and Cochrane were consulted. There was no restriction on the year of publication and language. Data of systematic reviews from April 2017 to September to 2017 were analyzed. The meta-analysis was conducted using RevMan 5.3 software provided by the Cochrane Collaboration. From a total of 570 articles, 9 manuscripts were included in this review. They analy onzed women with breast cancer and control patients, of which 10% and 90% were in the reproductive period and after menopause, respectively. The lowest level of melatonin was found in approximately 55% of studies with breast cancer in post-menopause. The metanalyses of the studies demonstrated low levels of melatonin in breast cancer patients (n=963) compared with control patients (n= 1332), with a mean difference between the studies of 8722;3.54 (CI8722;6.01,8722;1.06). Another difference found was in the comparison between smoking patients, with an average difference between 1.80 [0.97-2.63]. Our data suggest that low levels of melatonin might be a risk factor for breast cancer.

RESUMO O câncer de mama é comum em mulheres, mas sua etiologia ainda não é totalmente compreendida. Vários fatores podem contribuir para sua gênese, genética, estilo de vida e meio ambiente. A melatonina pode estar envolvida no processo de câncer de mama. Portanto, o objetivo deste estudo é avaliar a influência dos níveis de melatonina no câncer de mama por meio de uma revisão sistemática e meta-análise. Realizamos uma revisão sistemática de acordo com as recomendações do Prisma. Os principais bancos de dados, Medline, Embase e Cochrane, foram consultados. Não houve restrição quanto ao ano de publicação e idioma. Os dados de revisão sistemática obtidos de abril de 2017 a setembro a 2017 foram analisados. A meta-análise foi conduzida pelo programa RevMan 5.3 fornecido pela Cochrane Collaboration. De um total de 570 artigos, nove foram incluídos nesta revisão. As análises foram conduzidas em mulheres com câncer de mama e pacientes controle, dos quais 10% e 90% estavam no período reprodutivo e após a menopausa, respectivamente. O nível mais baixo de melatonina foi encontrado em aproximadamente 55% dos estudos com câncer de mama na pós-menopausa. As meta-análises de estudos demonstraram os baixos níveis de melatonina em doentes com câncer da mama (n=963), em comparação com os pacientes de controle (n=1.332), sendo a diferença de médias entre os estudos da 8722;3,54 (CI 8722;6,01, 8722;1,06). Outra diferença é demonstrada nas comparações entre pacientes fumantes, sendo a diferença da média entre 1,80 [0,97-2,63]. Nossos dados sugerem que baixos níveis de melatonina podem ser um fator de risco para câncer de mama.