Serum estrogen receptor bioactivity and breast cancer risk among postmenopausal women.
Endocr Relat Cancer
; 21(2): 263-73, 2014 Apr.
Article
in En
| MEDLINE
| ID: mdl-24322303
ABSTRACT
The estrogen levels of Asian women are different from those of Western women, and this could affect estrogen receptor (ER) bioactivity and breast cancer risk. We conducted a case-control study in 169 postmenopausal breast cancer cases and 426 matched controls nested within a population-based prospective cohort study, the Singapore Chinese Health Study, to evaluate the serum levels of estrogens and their receptor (ERα and ERß)-mediated estrogenic activities in relation to breast cancer risk. Breast cancer cases had higher levels of estrogens and ER-mediated bioactivities in baseline serum than the controls. Compared with those in the lowest quartile, women in the highest quartile for estrone (E1) or ERα-mediated bioactivity had increased breast cancer risk. After additional adjustment for ERß bioactivity, free estradiol, and E1 levels, serum ERα-mediated bioactivity remained associated with increased breast cancer risk. Compared with those in the lowest quartile, women in the highest quartile for ERα-mediated bioactivity had an odds ratio of 2.39 (95% CI=1.17-4.88; P for trend=0.016). Conversely, the positive association between E1 and cancer risk became null after adjustment for ERα-mediated bioactivity, suggesting that the effect of E1 could be mediated through ERα. Factor(s) contributing to increased ERα-mediated estrogenic bioactivity in serum and its role as a predictor for breast cancer risk need to be validated in future studies.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Breast Neoplasms
/
Postmenopause
/
Estrogen Receptor alpha
Type of study:
Etiology_studies
/
Observational_studies
/
Prognostic_studies
/
Risk_factors_studies
Limits:
Aged
/
Aged80
/
Female
/
Humans
/
Middle aged
Country/Region as subject:
Asia
Language:
En
Journal:
Endocr Relat Cancer
Journal subject:
ENDOCRINOLOGIA
/
NEOPLASIAS
Year:
2014
Document type:
Article