Postmenopausal levels of oestrogen, androgen, and SHBG and breast cancer: long-term results of a prospective study.

We assessed the association of sex hormone levels with breast cancer risk in a case-control study nested within the cohort of 7054 New York University (NYU) Women's Health Study participants who were postmenopausal at entry. The study includes 297 cases diagnosed between 6 months and 12.7 years after enrollment and 563 controls.

Circulating soluble Fas levels and risk of ovarian cancer.

Background: Dysregulation of apoptosis, specifically overexpression of soluble Fas (sFas), has been proposed to play a role in the development of ovarian cancer. The main objective of the present study was to evaluate serum sFas as a potential biomarker of ovarian cancer risk.

Methods: The association between serum sFas levels and the risk of ovarian cancer was examined in a case-control study nested within three prospective cohorts in New York (USA), Umeå (Sweden), and Milan (Italy).

Body mass index, serum sex hormones, and breast cancer risk in postmenopausal women.

Background: Obesity is associated with increased breast cancer risk among postmenopausal women. We examined whether this association could be explained by the relationship of body mass index (BMI) with serum sex hormone concentrations.

Methods: We analyzed individual data from eight prospective studies of postmenopausal women.

Reliability of serum iron, ferritin, nitrite, and association with risk of renal cancer in women.

Reliability of serum levels of iron, ferritin and nitrite (NO(2)(-)) over a 2-year period were evaluated in 40 healthy women (20 pre-menopausal and 20 post-menopausal), ages 39-65 years, from the New York University Women's Health Study (NYUWHS). Three blood samples per woman collected at yearly intervals were analyzed. Reliability coefficients (RCs) of serum iron, ferritin, and nitrite were 0.

Circulating levels of sex steroid hormones and risk of ovarian cancer.

Experimental and epidemiological evidence supports a role for sex steroid hormones in the pathogenesis of ovarian cancer. We investigated the association between ovarian cancer risk and pre-diagnostic blood concentrations of testosterone, androstenedione, DHEAS, estrone and SHBG. A case-control study nested within 3 cohorts, in New York (USA), Umeå (Sweden) and Milan (Italy), included 132 subjects with primary invasive epithelial ovarian cancer.

Validity of free testosterone and free estradiol determinations in serum samples from postmenopausal women by theoretical calculations.

In this study, we validated measurements of free testosterone (fT) and free estradiol (fE(2)) concentrations calculated from total serum concentrations of testosterone (T), estradiol (E(2)), and sex hormone-binding globulin (SHBG), measured by direct, commercial radioimmunoassays, by comparison with reference measurements obtained by dialysis plus an in-house radioimmunoassay after extraction and chromatographic purification. The study was conducted in serum samples from 19 postmenopausal women who were part of an ongoing prospective cohort study. We also performed sensitivity analyses to examine the robustness of the theoretical calculations.

Circulating levels of insulin-like growth factor-I and risk of ovarian cancer.

Insulin-like growth factor (IGF)-I, a mitogenic and anti-apoptotic peptide, has been implicated in the development of several cancers. We hypothesized that high circulating IGF-I concentrations may be associated with an increased risk of ovarian cancer. A case-control study was nested within 3 prospective cohorts in New York (USA), Umeå (Sweden) and Milan (Italy).

Insulin-like growth factor II and colorectal cancer risk in women.

Recently, a number of prospective studies showed evidence that the growth hormone/insulin-like growth factor I (IGF-I) axis may be important in the development of colorectal cancer. However, only a few studies have reported on the possible relationship of colorectal cancer risk with circulating levels of IGF-II, which are not growth hormone dependent and which do not vary with alterations in energy balance. In a case-control study of 102 cases and 200 matched controls nested within a cohort of 14,275 women in New York, we examined the relationship between colorectal cancer risk and prediagnostic serum levels of IGF-II.

Aspirin and lung cancer in women.

The association between aspirin use and lung cancer risk in women was examined in a case-control study nested in the New York University Women's Health Study, a large cohort in New York. Case subjects were all the 81 incident lung cancer cases who had provided information about aspirin use at enrollment and during the 1994-1996 follow up. Ten controls per case were randomly selected from among study participants who matched a case by age, menopausal status, and dates of enrollment and follow-up.

Body mass index in relation to ovarian cancer: a multi-centre nested case-control study.

The incidence of ovarian cancer is up to 10 times higher in Western countries than in rural Asia and Africa. One common consequence of a Western lifestyle is the development of excessive body weight and obesity. A multi-centre prospective study was conducted to investigate the association between body mass index (BMI) and ovarian cancer risk.

Aspirin and epithelial ovarian cancer.

Background: Epidemiological evidence suggests that chronic inflammation may influence ovarian carcinogenesis. The study objective was to examine the association between the commonly used anti-inflammatory drug aspirin and epithelial ovarian cancer.

Methods: The authors conducted a case-control study based in the New York University Women's Health Study cohort enrolled between 1985 and 1991 in New York City.

A cross-sectional study of IGF-I determinants in women.

Evidence is accumulating that elevated circulating insulin-like growth factor I (IGF-I) is related to increased cancer risk. The identification of hormonal, reproductive and lifestyle characteristics influencing its synthesis and bioavailability is of particular interest. Data from 400 women, who served as controls in two case-control studies nested within the same prospective cohort study, were combined.

Role of exogenous and endogenous hormones in endometrial cancer: review of the evidence and research perspectives.

Endometrial carcinoma is the most common cancer of the female reproductive organs in the United States. International comparisons reveal that the incidence of endometrial cancer vary widely between different countries with the highest rates observed in North America and Northern Europe, intermediate rates in Eastern Europe and Latin America, and lowest rates in Asia and Africa. International variation in endometrial cancer rates may represent differences in the distribution of known risk factors, which include obesity, postmenopausal estrogen replacement, ovarian dysfunction, diabetes mellitus, infertility, nulliparity, and tamoxifen use.

Reliability and validity of commercially available, direct radioimmunoassays for measurement of blood androgens and estrogens in postmenopausal women.

In large-scale epidemiological studies on endogenous sex steroids and cancer risk, direct immunoassays of circulating hormone levels have the advantage of being fast and comparatively inexpensive while requiring only small sample volumes. On the other hand, indirect assays after organic extraction and chromatographic prepurification have the advantage of reducing specific interferences and matrix effects and hence are thought to have better validity. We compared direct assays of testosterone (T, six different assays), Delta4-androstenedione (A, four assays), estrone (E(1), one assay), and 17beta-estradiol (E(2), five assays) with measurements obtained by an indirect assay in a representative subset of 20 postmenopausal women who were part of a large prospective cohort study.

Luteinizing hormone, its beta-subunit variant, and epithelial ovarian cancer: the gonadotropin hypothesis revisited.

The gonadotropin hypothesis postulates that excessive gonadotropin stimulation results in increased proliferation and subsequent malignant transformation of ovarian epithelium. The authors evaluated this hypothesis by analyzing the association between serum levels of wild-type luteinizing hormone (LH) and ovarian cancer risk. They also examined the relation between a variant of LH containing two missense point mutations (Trp(8)Arg and Ile(15)Thr) in its beta-subunit and ovarian cancer risk.

Serum carotenoids and breast cancer.

The consumption of vegetables and fruit may protect against many types of cancer, but research evidence is not compelling for breast cancer. Carotenoids are pigments that are present in most plants and have known antioxidant properties. Blood concentrations of carotenoids have been proposed as integrated biochemical markers of vegetable, fruit, and synthetic supplements consumed.

A prospective study of insulin-like growth factor-I, IGF-binding proteins-1, -2 and -3 and lung cancer risk in women.

Insulin-like growth factor-I (IGF-I) has mitogenic and anti-apoptotic properties and has been implicated in the development of breast, colorectum, prostate and lung cancer. IGF binding proteins (IGFBPs) are not only carrier proteins for IGFs but also hold a central position in IGF ligand-receptor interactions through influences on the bioavailability and distribution of IGFs in the extracellular environment. A case-control study nested within the New York University Women's Health Study Cohort included 93 women diagnosed with lung cancer at least 6 months after recruitment into the study.

Postmenopausal endogenous oestrogens and risk of endometrial cancer: results of a prospective study.

We assessed the association of postmenopausal serum levels of oestrogens and sex hormone-binding globulin (SHBG) with endometrial cancer risk in a case-control study nested within the NYU Women's Health Study cohort. Among 7054 women postmenopausal at enrolment, 57 cases of endometrial cancer were diagnosed a median of 5.5 years after blood donation.

Epithelial ovarian carcinoma and European birthplace of grandparents.

Objective: The aim of this study was to determine whether the risk of ovarian carcinoma was related to latitude or to genetically based patterns of European geographic origin.

Patients And Methods: We studied the countries of origin of European-born grandparents of 168 newly diagnosed patients in two hospitals in New York City, compared with 159 controls from similar neighborhoods. We measured the risk of this cancer associated with having one or more white, non-Jewish grandparents born in North Europe versus none or in South Europe versus none.

Serum insulin-like growth factor-I and breast cancer.

Insulin-like growth factor I (IGF-I) is a systemic hormone with potent mitogenic and anti-apoptotic properties, which could influence the proliferative behavior of normal breast cells. Limited epidemiological observations suggest that the hormone may play a role in the etiology of breast cancer, especially at pre-menopausal ages. In a prospective case-control study nested within a cohort of New York City women, IGF-I, IGF-binding protein 3 (IGFBP-3) and C peptide were measured in frozen serum samples from 172 pre-menopausal and 115 post-menopausal subjects who were subsequently diagnosed with breast cancer.