Journal Article

Marine n-3 fatty acid intake, glutathione <i>S</i>-transferase polymorphisms and breast cancer risk in post-menopausal Chinese women in Singapore

Manuela Gago-Dominguez, J.Esteban Castelao, Can-Lan Sun, David Van Den Berg, Woon-Puay Koh, Hin-Peng Lee and Mimi C. Yu

in Carcinogenesis

Volume 25, issue 11, pages 2143-2147
Published in print November 2004 | ISSN: 0143-3334
Published online November 2004 | e-ISSN: 1460-2180 | DOI: http://dx.doi.org/10.1093/carcin/bgh230
Marine n-3 fatty acid intake, glutathione S-transferase polymorphisms and breast cancer risk in post-menopausal Chinese women in Singapore

More Like This

Show all results sharing this subject:

  • Clinical Cytogenetics and Molecular Genetics

GO

Show Summary Details

Preview

We have previously found marine n-3 fatty acids to be inversely related to post-menopausal breast cancer in Chinese women from Singapore. Post-menopausal women with high [quartiles 2–4 (Q2–Q4)] versus low [quartile 1 (Q1)] intake exhibited a statistically significant reduction in risk of breast cancer after adjustment for potential confounders [relative risk (RR) = 0.66, 95% confidence interval (CI) = 0.50, 0.87]. Experimental studies have demonstrated a direct role for the peroxidation products of marine n-3 fatty acids in breast cancer protection. There is a suggestion that the glutathione S-transferases (GSTs) may be major catalysts in the elimination of these beneficial by-products. Therefore, we hypothesized that individuals possessing the low activity genotypes of GSTM1, GSTT1 and/or GSTP1 (i.e. the GSTM1 null, GSTT1 null and GSTP1 AB/BB genotypes, respectively) may exhibit a stronger marine n-3 fatty acid–breast cancer association than their high activity counterparts. The Singapore Chinese Health Study is a prospective investigation involving 35 298 middle-aged and older women, who were enrolled between April 1993 and December 1998. In this case–control analysis, nested within the Singapore Chinese Health Study, we compared 258 incident breast cancer cases with 670 cohort controls. Overall, breast cancer risk was unrelated to GSTM1 and GSTP1 genotypes. However, the GSTT1 null genotype was associated with a 30% reduced risk of breast cancer [odds ratio (OR) = 0.71, 95% CI = 0.52, 0.96]. Among women with high activity GST genotypes (i.e. GSTM1 positive, GSTT1 positive and GSTP1 AA), no marine n-3 fatty acid–breast cancer relationships were observed in either pre-menopausal or post-menopausal women at baseline. However, post-menopausal women possessing the combined GSTM1 null and GSTP1 AB/BB genotypes showed a statistically significant reduction in risk after adjustment for potential confounders (Q2–Q4 versus Q1, OR = 0.36, 95% CI = 0.14, 0.94). A similar relationship was observed among women with the combined GSTT1 null and GSTP1 AB/BB genotypes (OR = 0.26, 95% CI = 0.08, 0.78).

Keywords: BMI, body mass index; CI, confidence interval; GST, glutathione S-transferase; OR, odds ratio; Q, quartile; RR, relative risk.

Journal Article.  4019 words. 

Subjects: Clinical Cytogenetics and Molecular Genetics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.