Effect of dietary soy intake on breast cancer risk according to menopause and hormone receptor status

Abstract

Background: Although high soy consumption may be associated with lower breast cancer risk in Asian populations, findings from epidemiological studies have been inconsistent. Objective: We investigated the effects of soy intake on breast cancer risk among Korean women according to their menopausal and hormone receptor status. Methods: We conducted a case-control study with 358 incident breast cancer patients and 360 age-matched controls with no history of malignant neoplasm. Dietary consumption of soy products was examined using a 103-item food frequency questionnaire. Results: The estimated mean intakes of total soy and isoflavones from this study population were 76.5 g per day and 15.0 mg per day, respectively. Using a multivariate logistic regression model, we found a significant inverse association between soy intake and breast cancer risk, with a dose-response relationship (odds ratios (OR) (95% confidence interval (CI)) for the highest vs the lowest intake quartile: 0.36 (0.20-0.64)). When the data were stratified by menopausal status, the protective effect was observed only among postmenopausal women (OR (95% CI) for the highest vs the lowest intake quartile: 0.08 (0.03-0.22)). The association between soy and breast cancer risk did not differ according to estrogen receptor (ER)/progesterone receptor (PR) status, but the estimated intake of soy isoflavones showed an inverse association only among postmenopausal women with ER þ /PR þ tumors. Conclusions: Our findings suggest that high consumption of soy might be related to lower risk of breast cancer and that the effect of soy intake could vary depending on several factors.

Natural Products Modulate the Multifactorial Multidrug Resistance of Cancer

“…Epidemiological studies suggest an association between flavonoid intake and a reduced risk of certain cancers [121]. Flavonoids appear to work with no or little toxicity as large doses of these compounds (up to 500 mg/kg) have been administered to animals, with little or no toxicity reported [122].…”

Soja Para Consumo Humano: Breve Abordagem

“…Pesquisas desenvolvidas no Japão e na China, que possuem populações que consomem regularmente a soja na dieta, apresentaram índices reduzidos de doenças coronárias, câncer de próstata e o de mama, em comparação aos países onde a soja é pouco utilizada na alimentação humana (MANDARINO et al, 2002;CASÉ et al, 2005;GOETZL et al, 2007;CHO et al, 2010). Todavia, verificou-se que os japoneses, que migraram para o Ocidente, adotando assim novos hábitos alimentares em que a presença da soja não é tão representativa.…”

“…CÂNCER A soja é relacionada aos alimentos que previnem os diversos tipos de câncer, por possuir compostos anticarcinogênicos como isoflavonóides, e gliciteína, inibidores de saponinas e de tripsina, além de, substâncias formadas pela ação de bactérias presentes no intestino e as fibras presentes nos grãos (PAES, 1994;ESTEVES & MONTEIRO, 2001;MANDARINO et al, 2002;CHO et al, 2010). Os isoflavonóides são as substancias indicadas como os principais compostos presentes na soja, capazes de inibir e prevenir o aparecimento de vários canceres.…”

“…As pesquisas a respeito dos efeitos protetores dos compostos presentes na soja com relação ao câncer são relativamente recentes. Para se estabelecer o efeito de qualquer alimento na prevenção e no controle de doenças crônicas são necessários vários anos de pesquisa (MANDARINO et al, 2002;GOETZL et al, 2007;CHO et al, 2010).…”

Baicalein, unlike 4-hydroxytamoxifen but similar to G15, suppresses 17β-estradiol-induced cell invasion, and matrix metalloproteinase-9 expression and activation in MCF-7 human breast cancer cells

“…Certain epidemiological studies contribute one factor of these differences to dietary flavonoids (16)(17)(18). Furthermore, as their polyphenolic ring is similar to the steroid nucleus of 17β-estradiol (E2), certain flavonoids have been considered to exert an anti-estrogenic effect and are candidates for chemopreventive agents to reduce the risk of breast cancer (19).…”