Insulin-like growth factor 1 (IGF1), IGF binding protein 3 (IGFBP3), and breast cancer risk: Pooled individual data analysis of 17 prospective studies

Background: Insulin-like growth factor 1 (IGF1) stimulates mitosis and inhibits apoptosis. Some published results have shown an association between circulating IGF1 and breast-cancer risk, but it has been unclear whether this relationship is consistent or whether it is modified by IGF binding protein 3 (IGFBP3), menopausal status, oestrogen receptor status or other factors. The relationship of IGF1 (and IGFBP3) with breast-cancer risk factors is also unclear. The Endogenous Hormones and Breast Cancer Collaborative Group was established to analyse pooled individual data from prospective studies to increase the precision of the estimated associations of endogenous hormones with breast-cancer risk. Methods: Individual data on prediagnostic IGF1 and IGFBP3 concentrations were obtained from 17 prospective studies in 12 countries. The associations of IGF1 with risk factors for breast cancer in controls were examined by calculating geometric mean concentrations in categories of these factors. The odds ratios (ORs) with 95% CIs of breast cancer associated with increasing IGF1 concentrations were estimated by conditional logistic regression in 4790 cases and 9428 matched controls, with stratification by study, age at baseline, and date of baseline. All statistical tests were two-sided, and a p value of less than 0\ub705 was considered significant. Findings: IGF1 concentrations, adjusted for age, were positively associated with height and age at first pregnancy, inversely associated with age at menarche and years since menopause, and were higher in moderately overweight women and moderate alcohol consumers than in other women. The OR for breast cancer for women in the highest versus the lowest fifth of IGF1 concentration was 1\ub728 (95% CI 1\ub714-1\ub744; p<0\ub70001). This association was not altered by adjusting for IGFBP3, and did not vary significantly by menopausal status at blood collection. The ORs for a difference in IGF1 concentration between the highest and lowest fifth were 1\ub738 (95% CI 1\ub714-1\ub768) for oestrogen-receptor-positive tumours and 0\ub780 (0\ub757-1\ub713) for oestrogen-receptor-negative tumours (p for heterogeneity=0\ub7007). Interpretation: Circulating IGF1 is positively associated with breast-cancer risk. The association is not substantially modified by IGFBP3, and does not differ markedly by menopausal status, but seems to be confined to oestrogen-receptor-positive tumours

Some problems in the theory and application of graphical models

SIGLEAvailable from British Library Document Supply Centre-DSC:D206469 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Estimating group size and population density of Eurasian badgers Meles meles by quantifying latrine use

1. Conservation issues and a potential role in disease transmission generate the continued need to census Eurasian badgers Meles metes, but direct counts and sett counts present difficulties. The feasibility of estimating social group size and population density of badgers by quantifying their use of latrines was evaluated. 2. The number of latrines, or preferably the number of separate dung pits, which were known from bait-marking to be used by members of a social group, was positively correlated with adult group size estimated from mark-recapture studies at Woodchester Park and North Nibley (south-west England). In the latter study area both latrine-use measures were also significantly associated with total group size (i.e. including cubs and adults). 3. In spring 1997 and 1998, we quantified latrine use along strip transects, following linear features across four and five areas, respectively, in England, where badger density in summer was known from mark-recapture/resight studies. 4. Seven latrine-use measures were evaluated with regard to their potential to predict badger density. Each measure separately explained between 62% and 91% of the variation in population density in a given year. The simplest measures (latrines km(-1) and pits km(-1)) were most stable between years. 5. For these two simple latrine-use measures, a linear model without an intercept term explained the highest proportion of variation in population density. A stepwise procedure to produce the best model selected only one (latrines km(-1)) of the two measures as an explanatory variable., indicating that pits km(-1) is colinear with the former variable. 6. A badger census technique based on simple measurements of latrine use has great promise but needs to be validated across a wider range of badger populations, habitats, years, seasons and weather condition

Tobacco smoke and bladder cancer--in the European Prospective Investigation into Cancer and Nutrition.

Contains fulltext : 51070.pdf (publisher's version ) (Closed access)The purpose of the present study was to investigate the association between smoking and the development of bladder cancer. The study population consisted of 429,906 persons participating in the European Prospective Investigation into Cancer and Nutrition (EPIC), 633 of whom developed bladder cancer during the follow-up period. An increased risk of bladder cancer was found for both current- (incidence rate ratio 3.96, 95% confidence interval: 3.07-5.09) and ex- (2.25, 1.74-2.91) smokers, compared to never-smokers. A positive association with intensity (per 5 cigarettes) was found among current-smokers (1.18, 1.09-1.28). Associations (per 5 years) were observed for duration (1.14, 1.08-1.21), later age at start (0.75, 0.66-0.85) and longer time since quitting (0.92, 0.86-0.98). Exposure to environmental tobacco smoke (ETS) during childhood increased the risk of bladder cancer (1.38, 1.00-1.90), whereas for ETS exposure as adult no effect was detected. The present study confirms the strong association between smoking and bladder cancer. The indication of a higher risk of bladder cancer for those who start smoking at a young age and for those exposed to ETS during childhood adds to the body of evidence suggesting that children are more sensitive to carcinogens than adults

Circulating concentrations of folate and vitamin B12 in relation to prostate cancer risk: results from the European Prospective Investigation into Cancer and Nutrition study.

Contains fulltext : 69603.pdf (publisher's version ) (Closed access)BACKGROUND: Determinants of one-carbon metabolism, such as folate and vitamin B(12), have been implicated in cancer development. Previous studies have not provided conclusive evidence for the importance of circulating concentrations of folate and vitamin B(12) in prostate cancer etiology. The aim of the present study was to investigate the relationship between prostate cancer risk and circulating concentrations of folate and vitamin B(12) in a large prospective cohort. METHODS: We analyzed circulating concentrations of folate and vitamin B(12) in 869 cases and 1,174 controls, individually matched on center, age, and date of recruitment, nested within the European Prospective Investigation into Cancer and Nutrition cohort. Relative risks (RR) for prostate cancer were estimated using conditional logistic regression models. RESULTS: Overall, no significant associations were observed for circulating concentrations of folate (P(trend) = 0.62) or vitamin B(12) (P(trend) = 0.21) with prostate cancer risk. RRs for a doubling in folate and vitamin B(12) concentrations were 1.03 [95% confidence interval (95% CI), 0.92-1.16] and 1.12 (95% CI, 0.94-1.35), respectively. In the subgroup of cases diagnosed with advanced stage prostate cancer, elevated concentrations of vitamin B(12) were associated with increased risk (RR for a doubling in concentration, 1.69; 95% CI, 1.05-2.72, P(trend) = 0.03). No other subgroup analyses resulted in a statistically significant association. CONCLUSION: This study does not provide strong support for an association between prostate cancer risk and circulating concentrations of folate or vitamin B(12). Elevated concentrations of vitamin B(12) may be associated with an increased risk for advanced stage prostate cancer, but this association requires examination in other large prospective studies

Fruits and vegetables and renal cell carcinoma: Findings from the European Prospective Investigation into Cancer and Nutrition (EPIC)

We examined the association between fruits and vegetables and risk of renal cell carcinoma (RCC) in the European Prospective Investigation into Cancer and Nutrition (EPIC). Dietary intake data and complete follow-up information on cancer incidence were available for 375,851 participants recruited in EPIC centers of 8 countries. During an average follow-up of 6.2 years, 306 incident cases of RCC were identified. The associations of consumption of total vegetables, total fruits, combined total fruits and vegetables and specific subtypes of vegetables with RCC risk were analyzed using Cox proportional hazards, stratified by centre and adjusted for potential confounders. No significant associations between fruit and vegetable consumption and RCC risk were observed despite a wide range of intake. The estimated relative risks (95% confidence intervals [CI]) in men and women combined were 0.97 (0.85-1.11) per 40 g increase in vegetable intake, 1.03 (0.97-1.08) per 40 g increase in fruit intake and 1.02 (0.93-1.11) per 80 g increase in fruit and vegetable intake combined. Among the vegetable subtypes, an inverse association was observed for root vegetables (RR per 8 g increase: 0.88; 95% CI: 0.78-0.99). These results suggest that total consumption of fruits and vegetables is not related to risk of RCC, although we cannot exclude the possibility that very low consumption is related to higher risk. The relationship of specific fruit and vegetable subgroups with RCC risk warrant further investigation. (c) 2006 Wiley-Liss, Inc