| 1. |
|
|
| 2. |
- Rinaldi, S, et al.
(författare)
-
Physical activity, sex steroid, and growth factor concentrations in pre- and post-menopausal women : a cross-sectional study within the EPIC cohort
- 2014
-
Ingår i: Cancer Causes and Control. - : Springer Science and Business Media LLC. - 0957-5243 .- 1573-7225. ; 25:1, s. 111-124
-
Tidskriftsartikel (refereegranskat)abstract
- Increased physical activity (PA) is associated with a reduced risk of several cancers. PA may reduce cancer risk by changing endogenous hormones levels, but relatively little research has focused on this topic. The purpose of this study was to elucidate the relation between PA and endogenous hormone concentrations. A cross-sectional analysis of 798 pre- and 1,360 post-menopausal women included as controls in case-control studies on endogenous hormones (steroids, progesterone, sex-hormone-binding globulin (SHBG), and growth factors) levels, and cancer risk nested within European Prospective Investigation into Cancer and Nutrition cohort was performed. Multivariate regression analyses were performed to compare geometric mean levels of hormones and SHBG by categories of PA. In pre-menopausal women, active women had 19 % significantly lower concentrations of androstenedione, 14 % lower testosterone, and 20 % lower free testosterone than inactive women, while no differences were observed for estrogens, progesterone, SHBG, and growth factors. In post-menopausal women, active women had 18 % significantly lower estradiol and 20 % lower free estradiol concentrations than inactive women, while no differences were observed for the other hormones and SHBG. More vigorous forms of physical activity were associated with higher insulin-like growth factor-I concentrations. Adjustment for body mass index did not alter the associations. Overall, the percentage of variance in hormone concentrations explained by PA levels was < 2 %. Our results support the hypothesis of an influence, although small in magnitude, of PA on sex hormone levels in blood, independent of body size.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
- Lukanova, Annekatrin, et al.
(författare)
-
Body mass index, circulating levels of sex-steroid hormones, IGF-I and IGF-binding protein-3 : a cross-sectional study in healthy women.
- 2004
-
Ingår i: European Journal of Endocrinology. - 0804-4643 .- 1479-683X. ; 150:2, s. 161-171
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Excess weight has been associated with increased risk of cancer at several organ sites. In part, this effect may be modulated through alterations in the metabolism of sex steroids and IGF-I related peptides. The objectives of the study were to examine the association of body mass index (BMI) with circulating androgens (testosterone, androstenedione and dehydroepiandrosterone sulfate (DHEAS)), estrogens (estrone and estradiol), sex hormone-binding globulin (SHBG), IGF-I and IGF-binding protein (IGFBP)-3, and the relationship between sex steroids, IGF-I and IGFBP-3. DESIGN AND METHODS: A cross-sectional analysis was performed using hormonal and questionnaire data of 620 healthy women (177 pre- and 443 post-menopausal). The laboratory measurements of the hormones of interest were available from two previous case-control studies on endogenous hormones and cancer risk. RESULTS: In the pre-menopausal group, BMI was not related to androgens and IGF-I. In the post-menopausal group, estrogens, testosterone and androstenedione increased with increasing BMI. The association with IGF-I was non-linear, with the highest mean concentrations observed in women with BMI between 24 and 25. In both pre- and post-menopausal subjects, IGFBP-3 did not vary across BMI categories and SHBG decreased with increasing BMI. As for the correlations between peptide and steroid hormones, in the post-menopausal group, IGF-I was positively related to androgens, inversely correlated with SHBG, and not correlated with estrogens. In the pre-menopausal group, similar but weaker correlations between IGF-I and androgens were observed. CONCLUSIONS: These observations offer evidence that obesity may influence the levels of endogenous sex-steroid and IGF-related hormones in the circulation, especially after menopause. Circulating IGF-I, androgens and SHBG appear to be related to each other in post-menopausal women.
|
|
| 7. |
|
|
| 8. |
- Ose, J., et al.
(författare)
-
Insulin-like growth factor I and risk of epithelial invasive ovarian cancer by tumour characteristics: results from the EPIC cohort
- 2015
-
Ingår i: British Journal of Cancer. - : Springer Science and Business Media LLC. - 1532-1827 .- 0007-0920. ; 112:1, s. 162-166
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Prospective studies on insulin-like growth factor I (IGF-I) and epithelial ovarian cancer (EOC) risk are inconclusive. Data suggest risk associations vary by tumour characteristics. Methods: We conducted a nested case-control study in the European Prospective Investigation into Cancer and Nutrition (EPIC) to evaluate IGF-I concentrations and EOC risk by tumour characteristics (n = 565 cases). Multivariable conditional logistic regression models were used to estimate associations. Results: We observed no association between IGF-I and EOC overall or by tumour characteristics. Conclusions: In the largest prospective study to date was no association between IGF-I and EOC risk. Pre-diagnostic serum IGF-I concentrations may not influence EOC risk.
|
|
| 9. |
|
|
| 10. |
- Tsilidis, K. K., et al.
(författare)
-
Oral contraceptive use and reproductive factors and risk of ovarian cancer in the European Prospective Investigation into Cancer and Nutrition
- 2011
-
Ingår i: British Journal of Cancer. - London : Springer Science and Business Media LLC. - 1532-1827 .- 0007-0920. ; 105:9, s. 1436-1442
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: It is well established that parity and use of oral contraceptives reduce the risk of ovarian cancer, but the associations with other reproductive variables are less clear. METHODS: We examined the associations of oral contraceptive use and reproductive factors with ovarian cancer risk in the European Prospective Investigation into Cancer and Nutrition. Among 327 396 eligible women, 878 developed ovarian cancer over an average of 9 years. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazard models stratified by centre and age, and adjusted for smoking status, body mass index, unilateral ovariectomy, simple hysterectomy, menopausal hormone therapy, and mutually adjusted for age at menarche, age at menopause, number of full-term pregnancies and duration of oral contraceptive use. RESULTS: Women who used oral contraceptives for 10 or more years had a significant 45% (HR, 0.55; 95% CI, 0.41-0.75) lower risk compared with users of 1 year or less (P-trend, <0.01). Compared with nulliparous women, parous women had a 29% (HR, 0.71; 95% CI, 0.59-0.87) lower risk, with an 8% reduction in risk for each additional pregnancy. A high age at menopause was associated with a higher risk of ovarian cancer (>52 vs <= 45 years: HR, 1.46; 95% CI, 1.06-1.99; P-trend, 0.02). Age at menarche, age at first full-term pregnancy, incomplete pregnancies and breastfeeding were not associated with risk. CONCLUSION: This study shows a strong protective association of oral contraceptives and parity with ovarian cancer risk, a higher risk with a late age at menopause, and no association with other reproductive factors. British Journal of Cancer (2011) 105, 1436-1442. doi:10.1038/bjc.2011.371 www.bjcancer.com Published online 13 September 2011 (C) 2011 Cancer Research UK
|
|
