Associations between adiposity and repetitive element DNA methylation in healthy postmenopausal women

Abstract

Aim: To describe the association between adiposity and repetitive element DNA methylation in healthy postmenopausal women. Patients & methods: A cross-sectional study was conducted using baseline information from 289 women who participated in the Alberta Physical Activity and Breast Cancer Prevention trial. Results: After adjusting for important confounders,  long interspersed nuclear element-1 methylation was positively associated with intra-abdominal fat area (p = 0.03), body fat percent (p = 0.048), fat mass (p = 0.01), waist circumference (p = 0.03), hip circumference (p = 0.001), BMI (p = 0.03), current weight (p = 0.002), weight at age 20 (p = 0.02) and adulthood weight gain (p = 0.03). No significant associations were found between any of the adiposity measures and Alu methylation. Conclusion: Current and historical adiposity measures are positively associated with long interspersed nuclear element-1 methylation in healthy postmenopausal women.

Keywords::

• adiposity
• Alu
• body fat
• DNA methylation
• LINE-1
• postmenopausal
• repetitive elements

Acknowledgements

The ALPHA trial study set-up was performed by KVD hoek and M Orenstein. The study coordinators were R Crosby and A-L Tamburrini. Data preparation for this ancillary study was done by Q Wang. DNA extraction and quantification was performed by A Chan and M Dean in the Translational Laboratory of the Tom Baker Cancer Center. N Brockton provided advice on the DNA extraction protocols developed for this study.

Financial & competing interests disclosure

The ALPHA trial was originally funded by a research grant from the Canadian Breast Cancer Research Alliance and the ancillary study is funded by grants from the Canadian Institutes of Health Research (CIHR) and the Canadian Cancer Society. Funding for the DNA extraction was provided by an Alberta Cancer Foundation grant for the Biospecimen Processing Unit within the Translational Laboratories (TL) at the Tom Baker Cancer Center (TBCC). DJ Boyne was supported by funding from the Queen’s University Terry Fox Foundation Training Program in Transdisciplinary Cancer Research in partnership with CIHR and an Ontario Graduate Scholarship. CM Friedenreich was supported by an Alberta Innovates Health Solutions Health Senior Scholar Award and by the Alberta Cancer Foundation Weekend to End Women’s Cancers Breast Cancer Chair. KS Courneya is supported by the Canada Research Chairs Program. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Ethical conduct of research

Informed consent was obtained from all participants. This study was approved by the Alberta Cancer Research Ethics Committee and the ethics review boards of the University of Calgary, University of Alberta, and Queen’s University.

Additional information

Funding

The ALPHA trial was originally funded by a research grant from the Canadian Breast Cancer Research Alliance and the ancillary study is funded by grants from the Canadian Institutes of Health Research (CIHR) and the Canadian Cancer Society. Funding for the DNA extraction was provided by an Alberta Cancer Foundation grant for the Biospecimen Processing Unit within the Translational Laboratories (TL) at the Tom Baker Cancer Center (TBCC). DJ Boyne was supported by funding from the Queen’s University Terry Fox Foundation Training Program in Transdisciplinary Cancer Research in partnership with CIHR and an Ontario Graduate Scholarship. CM Friedenreich was supported by an Alberta Innovates Health Solutions Health Senior Scholar Award and by the Alberta Cancer Foundation Weekend to End Women’s Cancers Breast Cancer Chair. KS Courneya is supported by the Canada Research Chairs Program. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. No writing assistance was utilized in the production of this manuscript.