Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology
-
Cancer Epidemiol. Biomarkers Prev. · Nov 2007
Multicenter StudyCYP17 genetic variation and risk of breast and prostate cancer from the National Cancer Institute Breast and Prostate Cancer Cohort Consortium (BPC3).
CYP17 encodes cytochrome p450c17alpha, which mediates activities essential for the production of sex steroids. Common germ line variation in the CYP17 gene has been related to inconsistent results in breast and prostate cancer, with most studies focusing on the nonsynonymous single nucleotide polymorphism (SNP) T27C (rs743572). We comprehensively characterized variation in CYP17 by direct sequencing of exons followed by dense genotyping across the 58 kb region around CYP17 in five racial/ethnic populations. ⋯ We also observed marginally significant associations with breast cancer for rs4919687 (GA versus GG, OR, 1.04; 95% CI, 0.97-1.12, AA versus GG, OR, 1.17; 95% CI, 1.03-1.34; P trend=0.03) and rs4919682 (CT versus CC, OR, 1.04; 95% CI, 0.97-1.12; TT versus CC, OR, 1.16; 95% CI, 1.01-1.33; P trend=0.04). Common variation at CYP17 was not associated with circulating sex steroid hormones in men or postmenopausal women. Our findings do not support the hypothesis that common germ line variation in CYP17 makes a substantial contribution to postmenopausal breast or prostate cancer susceptibility.
-
Cancer Epidemiol. Biomarkers Prev. · Nov 2007
Bronchial epithelial Ki-67 index is related to histology, smoking, and gender, but not lung cancer or chronic obstructive pulmonary disease.
To determine whether increased bronchial epithelial proliferation is associated with histology, smoking status, gender, age, chronic obstructive pulmonary disease (COPD), or lung cancer. ⋯ Smoking status, bronchial histology, and gender were significantly associated with Ki-67 index. No increase in Ki-67 index was found in the nonmalignant epithelium of patients with lung cancer or COPD. Although Ki-67 index may provide insight into the short-term effects of chemoprevention agents on cell proliferation, its lack of association with lung cancer or COPD raises question regarding its utility as a lung cancer risk biomarker.
-
Cancer Epidemiol. Biomarkers Prev. · Oct 2007
Relationship between age maximum height is attained, age at menarche, and age at first full-term birth and breast cancer risk.
Several pubertal and reproductive events are well established risk factors for breast cancer. Age maximum height attained is an understudied potential breast cancer risk factor that may affect risk through mechanisms different from those of other pubertal and reproductive events. We assessed the relationships between different pubertal/reproductive events and risk of different types of breast cancer in a prospective cohort of 27,536 women. ⋯ This association was primarily limited to more aggressive tumors, specifically those that were estrogen receptor-negative (hazard ratio, 1.9; 95% CI, 1.0-3.9) and diagnosed at a regional or distant stage (hazard ratio, 1.8; 95% CI, 1.0-3.1). There was no difference in the relation of age at menarche with breast cancer by tumor stage, whereas late age at first full-term pregnancy primarily increased risks of less-aggressive disease, including lobular, estrogen receptor-positive, and localized stage tumors. Age at maximum height seems to be an independent risk factor for breast cancer that is more strongly associated with relatively aggressive tumors that have a poorer prognosis compared with the types of tumors that are associated with ages at menarche and first full-term birth.
-
Cancer Epidemiol. Biomarkers Prev. · Sep 2007
A prospective study of body size and breast cancer in black women.
The relation of body mass index (BMI) and weight gain to breast cancer risk is complex, and little information is available on Black women, among whom the prevalence of obesity is high. We assessed BMI and weight gain in relation to breast cancer risk in prospective data from the Black Women's Health Study. In 1995, 59,000 African American women enrolled in the Black Women's Health Study by completing mailed questionnaires. ⋯ The findings indicate that being overweight at age 18 years is associated with a reduced risk of both premenopausal and postmenopausal breast cancer in African American women. Understanding the reasons for the association may help elucidate the pathways through which adolescent exposures influence breast cancer risk. The lack of association of obesity with receptor-negative tumors in postmenopausal African American women may partially explain why breast cancer incidence in older Black women is not high relative to other ethnic groups in spite of the high prevalence of obesity in Black women.
-
Cancer Epidemiol. Biomarkers Prev. · Sep 2007
Randomized Controlled Trial Multicenter StudyThe polyp prevention trial continued follow-up study: no effect of a low-fat, high-fiber, high-fruit, and -vegetable diet on adenoma recurrence eight years after randomization.
The Polyp Prevention Trial (PPT) was a multicenter randomized clinical trial to evaluate the effects of a high-fiber (18 g/1,000 kcal), high-fruit and -vegetable (3.5 servings/1,000 kcal), and low-fat (20% of total energy) diet on the recurrence of adenomatous polyps in the large bowel over a period of 4 years. Although intervention participants reported a significantly reduced intake of dietary fat, and increased fiber, fruit, and vegetable intakes, their risk of recurrent adenomas was not significantly different from that of the controls. Since the PPT intervention lasted only 4 years, it is possible that participants need to be followed for a longer period of time before treatment differences in adenoma recurrence emerge, particularly if diet affects early events in the neoplastic process. ⋯ There were no significant intervention-control group differences in the relative risk for recurrence of an advanced adenoma (1.06; 0.81-1.39) or multiple adenomas (0.92; 0.77-1.10). We also used a multiple imputation method to examine the cumulative recurrence of adenomas through the end of the PPT-CFS: the intervention-control relative risk (95% confidence intervals) for any adenoma recurrence was 1.04 (0.98-1.09). This study failed to show any effect of a low-fat, high-fiber, high-fruit and -vegetable eating pattern on adenoma recurrence even with 8 years of follow-up. (Cancer Epidemiol Biomarkers Prev 2007;16(9):1745-52).