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F Z Stanczyk

Publications and source records attributed to F Z Stanczyk.

At least 37 records · Page 2Linked to original sources
PubMed2001

Altered balance between the 5 alpha-reductase and aromatase pathways of androgen metabolism during controlled ovarian hyperstimulation with human menopausal gonadotropins.

PURPOSE: To evaluate androgen production and metabolism during controlled ovarian hyperstimulation. METHODS: Five women, aged 33-42, were studied. All participants were undergoing controlled ovarian hyperstimulation with gonadotropin-releasing hormone agonist and human menopausal gonadotropins. Serum estradiol, estrone, androstenedione, testosterone, 3 alpha-androstanediol glucuronide, and sex hormone-binding globulin levels were measured at 6 time points during the cycle. RESULTS: The levels of all steroids increased significantly from baseline during controlled ovarian hyperstimulation. Mean total testosterone levels increased from 0.29 +/- 0.05 ng/mL to 0.58 +/- 0.07 ng/mL after gonadotropin stimulation. Sex hormone-binding gonadotropin levels increased from 50 +/- 16 nM to 73 +/- 12 nM after gonadotropin stimulation. Estrone/androstenedione and estradiol/testosterone ratios, reflecting the aromatase pathway, increased whereas 3 alpha-androstanediol glucuronide/androstenedione and 3 alpha-androstanediol glucuronide/testosterone ratios, reflecting 5 alpha-reductase activity, decreased. CONCLUSIONS: Controlled ovarian hyperstimulation with human menopausal gonadotropins results in increased serum testosterone and androstenedione levels. Whereas there is an enhancement in androgen metabolism by aromatase, 5 alpha-reductase activity with regard to androgen metabolism is diminished.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed2001

Plasma progesterone, dehydroepiandrosterone sulfate and estriol levels during labor induction with a sustained-release prostaglandin E2 vaginal insert.

OBJECTIVE: To measure plasma progesterone, dehydroepiandrosterone sulfate (DHEAS) and estriol levels in women induced for labor with a sustained-release vaginal polymer prostaglandin E2 insert, and to analyze the relationships between the changes in hormone levels and Bishop score. METHODS: Twelve primipara and 12 multipara were treated with a sustained-release polymer vaginal prostaglandin E2 insert (0.3 mg/h) for up to 24 h. The Bishop score was assessed at the start and end of therapy, and serum samples were collected at 4-h intervals. Plasma levels of progesterone, DHEAS and estriol were measured by specific radioimmunoassays. RESULTS: Exposure averaged 13.5 +/- 7.2 h. Progesterone levels decreased in the majority of patients (79.2%) after the start of therapy. Higher baseline DHEAS and estriol levels were observed among women who achieved an improvement in Bishop score of at least 4 during prostaglandin E2 treatment. CONCLUSIONS: Higher DHEAS and estriol levels prior to labor induction with prostaglandin E2 may be indicators of a favorable labor outcome. Additional studies are needed to substantiate the decrease in progesterone levels observed in this study and the importance of this phenomenon for the mechanism of labor induction with prostaglandin E2.

Administration, Intravaginal↗
PubMed2001

Prostate-specific antigen and human glandular kallikrein 2 are markedly elevated in urine of patients with polycystic ovary syndrome.

Prostate-specific antigen (PSA) is a well-established tumor marker of prostatic adenocarcinoma. Human glandular kallikrein 2 (hK2), another serine protease closely related to PSA, is also gaining ground as a promising diagnostic tool in prostate cancer. The expression of these 2 proteases is known to be regulated by androgens and progestins in hormonally responsive tissues, such as the male prostate and the female breast. Previously, we have shown that serum PSA levels in normal women are very low but still detectable by ultrasensitive PSA immunoassays. We have also demonstrated that some women with hyperandrogenic syndromes have elevated serum PSA levels. In this study, we have measured urinary PSA and urinary hK2 levels in 35 polycystic ovary syndrome (PCOS) patients and compared them to those of 41 age-matched controls. We found that urinary PSA levels were significantly higher (P < 0.0001) in PCOS patients (mean +/- SE = 820 +/- 344 ng/L) than in the controls (mean +/- SE = 4.3 +/- 1.8 ng/L). Similarly, the difference between urinary hK2 of patients (mean +/- SE = 8.2 +/- 3.1 ng/L) and controls (0.5 +/- 0.3 ng/L) was also significant (P < 0.001). A weak correlation was observed between urinary PSA and serum 3 alpha-androstanediol glucuronide (r(s) = 0.42, P = 0.03) as well as between urinary PSA and serum testosterone (r(s) = 0.40, P = 0.04). The results of this study indicate that urinary PSA, and possibly urinary hK2, are promising markers of hyperandrogenism in females suffering from PCOS.

Adult↗
PubMed2001

Sources of elevated serum androgens in postmenopausal women who develop breast cancer.

Postmenopausal women with elevated serum androgens are at an increased risk of breast cancer. High dehydroepiandrosterone sulfate concentrations in these women suggest increased adrenal secretion. Both the adrenals and ovaries could contribute to elevated concentrations of androstenedione (Delta4A). 11beta-Hydroxyandrostenedione (11betaOHA) is elevated, and the Delta4A:11betaOHA ratio is depressed when the adrenals are the primary source of elevated Delta4A in women. Conversely, Delta4A:11betaOHA is elevated when the ovaries are the primary source. We prospectively evaluated associations of serum 11betaOHA and Delta4A:11betaOHA with breast cancer in the Columbia, Missouri Serum Bank to identify the source of elevated Delta4A related to risk. Fifty-three postmenopausal women who were not taking estrogens when they donated blood and were diagnosed with breast cancer up to 10 years later (median, 2.9 years) served as cases. Two controls, who were also postmenopausal and not taking estrogens, were matched to each case on age, date, and time of blood collection. Serum Delta4A concentration was significantly (trend P = 0.02) positively associated with breast cancer risk. Adjusted risk ratios for women in the lowest to highest tertiles were 1.0, 1.6, and 2.4 [95% confidence interval (CI), 0.9-6.5]. However, neither 11betaOHA concentration nor Delta4A:11betaOHA was related to risk. Comparable risk ratios were 1.0, 1.2, and 1.4 (95% CI, 0.5-3.6) for 11betaOHA and 1.0, 1.2, and 1.2 (95% CI, 0.4-3.5) for Delta4A:11betaOHA. Our results suggest that neither the ovaries nor adrenals are the predominant source of elevated serum Delta4A in postmenopausal women who develop breast cancer, but rather both may contribute.

Adrenal Glands↗
PubMed2001

Insulin-like growth factors and prostate cancer: a population-based case-control study in China.

Insulin-like growth factors (IGFs) have potent mitogenic and antiapoptotic effects on prostate epithelial cells. Through modulation of IGF bioactivity and other mechanisms, IGF-binding proteins (IGFBPs) also have growth-regulatory effects on prostate cells. Recently, IGF-I and IGFBP-3 have been implicated in prostate cancer risk among Western populations. To assess whether IGF-I, IGF-II, IGFBP-1, or IGFBP-3 are also associated with prostate cancer in a low-risk population, we measured plasma levels of these factors among 128 newly diagnosed prostate cancer cases and 306 randomly selected population controls in Shanghai, China. Relative to the lowest quartile of IGF-I levels, men in the highest quartile had a 2.6-fold higher prostate cancer risk, with a significant trend [odds ratio (OR) = 2.63; 95% confidence interval (95% CI) = 1.19-5.79; P(trend) = 0.01]. In contrast, men in the highest quartile of IGFBP-3 levels had a 46% decreased risk relative to the lowest quartile (OR = 0.54; 95% CI = 0.26-1.15; P(trend) = 0.08). A similar but less distinct result was observed for IGFBP-1 (OR = 0.60; 95% CI = 0.31-1.17; P(trend) = 0.25). Men in the highest quartile for the IGF-I:IGFBP-3 molar ratio (an indirect measure of free IGF-I) had a 2.5-fold higher risk compared with the lowest quartile (OR = 2.51; 95% CI = 1.32-4.75, P(trend) < 0.001). These associations were more pronounced after adjustment for serum 5alpha-androstane-3alpha,17beta-diol glucuronide and sex hormone-binding globulin levels. There was no significant association with IGF-II levels. Our findings in a low-risk population provide evidence that IGF-I, IGFBP-3, and IGFBP-1 are determinants of prostate cancer and indicate that additional studies are needed to evaluate their effects on ethnic and geographic incidence differentials and to elucidate carcinogenic mechanisms.

Aged↗
PubMed2001

Lifestyle determinants of 5alpha-reductase metabolites in older African-American, white, and Asian-American men.

Men with higher endogenous 5alpha-reductase activity may have higher prostate cancer risk. This hypothesis raises two questions: (a) Could racial differences in 5alpha-reductase activity explain the observed racial differences in prostate cancer risk? and (b) Could a man reduce his activity level by modifying his lifestyle? To address these questions, we measured two hormonal indices of 5alpha-reductase activity [serum levels of androstane-3alpha-17beta-diol glucuronide (3alpha-diol G) and androsterone glucuronide (AG)] in healthy, older African-American, white, and Asian-American men, who are at high, intermediate, and low prostate cancer risk, respectively. We also examined associations between these metabolite levels and such lifestyle characteristics as body size and physical activity as well as select aspects of medical history and family history of prostate cancer. Men included in this cross-sectional analysis (n = 1054) had served as control subjects in a population-based case-control study of prostate cancer we conducted in California, Hawaii, and Vancouver, Canada and provided information on certain personal attributes and donated blood between March 1990 and March 1992. In this study, concentrations of 3alpha-diol G declined significantly with age and increased significantly with body mass index. Mean levels of 3alpha-diol G, adjusted for age and body mass index, were 6.1 ng/ml in African-Americans, 6.9 ng/ml in whites and 4.8 ng/ml in Asian-Americans. These differences were statistically significant (African-Americans versus whites: P < 0.01; whites versus Asian-Americans: P < 0.001). Concentrations of AG decreased significantly with age, but only in whites, and were unrelated to any of the reported personal attributes. Mean levels of AG, adjusted for age, were 44.1 ng/ml in African-Americans, 44.9 ng/ml in whites, and 37.5 ng/ml in Asian-Americans (Asian-Americans versus whites, P < 0.001). In conclusion, older African-American and white men have similar levels of these two indices of 5alpha-reductase activity, and these levels are higher than those of older Asian-American men. This difference may be related to the lower prostate cancer risk in Asian-Americans.

Age Distribution↗
PubMed2001

Polymorphic markers in the SRD5A2 gene and prostate cancer risk: a population-based case-control study.

It has been suggested that the activity of the steroid 5alpha-reductase type II enzyme (encoded by the SRD5A2 gene) may be associated with prostate cancer risk and that population differences in this enzyme's activity may account for part of the substantial racial/ethnic disparity in prostate cancer risk. To provide etiological clues, we evaluated the relationships of four polymorphic markers in the SRD5A2 gene, specifically, A49T (a substitution of threonine for alanine at codon 49), V89L (a substitution of leucine for valine at codon 89), R227Q (a substitution of glutamine for arginine at codon 227), and a (TA)n dinucleotide repeat, with prostate cancer risk in a population-based case-control study in China, a population with the lowest reported prostate cancer incidence rate in the world. Genotypes of these four markers were determined from genomic DNA of 191 incident cases of prostate cancer and 304 healthy controls using PCR-based assays, and serum androgen levels were measured in relation to these genotypes. All study subjects had the wild-type AA genotype of the A49T marker, and 99% had the RR genotype of the R227Q marker. For the V89L marker, prevalences of the LL, VV, and VL genotypes among controls were 35%, 21%, and 45%, respectively. Compared with men with the VV genotype, those with the LL genotype had a statistically nonsignificant 12% reduced risk (odds ratio = 0.88, 95% confidence interval, 0.53-1.47). In addition, men with the LL genotype had significantly higher serum levels of testosterone and significantly lower serum levels of 5alpha-androstane-3alpha,17beta-diol glucuronide than men with other genotypes. Men heterozygous for the (TA)0 allele of the (TA)n marker had a modest, statistically nonsignificant risk reduction (odds ratio = 0.67; 95% confidence interval, 0.39-1.12) compared with men homozygous for the (TA)0 allele, along with significantly higher serum dihydrotestosterone levels. The observed V89L genotype prevalences and the association between V89L genotypes and serum androgen levels support the hypothesis that genotypes associated with lower levels of 5alpha-reductase activity are more common in low-risk populations. Although we found no statistically significant associations of these SRD5A2 polymorphisms with prostate cancer risk, a small effect of these markers cannot be ruled out because of the rarity of certain marker genotypes. Larger studies are needed to further clarify the role of these markers and to elucidate whether genetic diversity of the SRD5A2 gene, alone or in combination with other susceptibility genes, can help explain the large racial/ethnic differences in prostate cancer risk.

Adult↗
PubMed2001

Comparison of estrogen and androgen levels after oral estrogen replacement therapy.

OBJECTIVE: To assess the extent of accumulation of circulating estrone (E1), total and free estradiol (E2) and estrone sulfate (E1S) levels in postmenopausal women receiving prolonged oral E2 therapy and to determine the effect of increased estrogenicity on free testosterone levels. STUDY DESIGN: Descriptive study involving 14 healthy postmenopausal women during a three-year period. Group 1 (n = 7) took a placebo. Group 2 (n = 7) took 1 mg micronized E2 daily. Blood samples were taken at one, two and three years. E2, E1 and total testosterone were quantified by radioimmunoassay (RIA) following extraction and celite chromatography. Free testosterone and E2 were calculated. Sex hormone-binding globulin (SHBG) and E1S were quantified by RIA. RESULTS: In the control group, none of the hormone levels changed significantly. Free testosterone decreased 49% in women taking E2 replacement as compared to a 7% decline in women taking placebo. In women taking E2 replacement, E1, E2, E1S, free E2 and SHBG levels increased 10, 6, 51, 2 and 2 times, respectively, between baseline and year 3. CONCLUSION: E1, E2 and E1S levels significantly increased with E2 replacement. Free testosterone levels decreased with E2 replacement. Testosterone replacement may be warranted when giving postmenopausal women estrogen replacement therapy.

Administration, Oral↗
PubMed2000

Associations between circulating sex steroid hormones and cognition in normal elderly women.

OBJECTIVE: To provide exploratory analyses of associations between levels of several sex hormones and cognitive performance in elderly women. BACKGROUND: Sex steroid hormones are implicated in the cognitive processes of the adult brain. Comparing cognitive performance across or between conditions associated with different hormone levels, such as phases of the menstrual cycle, surgical menopause, and estrogen replacement therapy suggests conditions with higher levels of estrogen are associated with better verbal memory and possibly worse visuospatial ability. METHOD: The authors measured circulating sex hormone levels in 39 highly educated, nondemented, predominantly white elderly women. Levels were correlated with neuropsychological performance, controlling for age, education, frequency of prior testing, use of estrogen replacement, and depression. RESULTS: High estradiol levels were associated with better delayed verbal memory and retrieval efficiency, whereas low levels were associated with better immediate and delayed visual memory. Levels of testosterone were related positively to verbal fluency. Levels of progesterone and androstenedione were unrelated to cognitive performance. CONCLUSIONS: Both estrogen and testosterone showed associations with cognitive performance. Estrogen may enhance, and depress, specific cognitive skills.

Aged↗
PubMed2000

Apoptosis may be an early event of progestin therapy for endometrial hyperplasia.

OBJECTIVE: The aim of this study was to investigate the role of apoptosis during progestin therapy for the treatment of endometrial hyperplasia. METHODS: Pre- and posttreatment paraffin-embedded endometrial tissue samples from 19 women with endometrial hyperplasia were examined for changes in glandular cellularity and apoptotic activity related to the administration of progestins. Twelve patients were successfully treated with progestin therapy and 7 patients failed treatment. Glandular cellularity was assessed based on calculating the average number of cells per gland obtained on histologic examination of hematoxylin and eosin stained tissue sections. Apoptotic activity was assessed on the same tissue sections by counting the average number of apoptotic cells per 10 high power fields (hpf) using the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) assay. The effects of progesterone on apoptotic activity in a low-grade endometrial adenocarcinoma cell line (Ishikawa cells) was also examined using an ELISA cell death detection kit. RESULTS: Glandular cellularity significantly decreased with progestin therapy in both treatment outcome groups. The reduction in cells per gland was significantly greater in the group of successfully treated cases compared to the treatment failures (P = 0.005). However, within the successfully treated group, in situ detection of apoptotic cells using the TUNEL assay showed no statistical difference between pre- and posttreatment endometrial samples. Interestingly, a significant decrease in apoptosis was found in posttreatment samples of the group with persistent hyperplasia. The average number of apoptotic cells detected in 10 hpf was reduced from 7.9 prior to treatment to 3.1 after progestin therapy (P = 0.03). In the progesterone-treated Ishikawa cell line, an increase in apoptotic activity started at 24 h, reached a peak at 48 h, and continued up to 72 h of hormone treatment. At 48 h, apoptotic activity was 42.6% greater than in the untreated control (P = 0.04). By 72 h of progesterone treatment, apoptosis was 37.2% greater in the treated cells compared to the noninoculated cells (P = 0.04). CONCLUSIONS: Progestin-induced apoptosis may occur during the early period of treatment for endometrial hyperplasia. Compared to the fully responsive group, persistent endometrial hyperplasia may have intrinsically different molecular mechanisms in response to progestin therapy.

Adult↗
PubMed2000

Serum inhibin B levels in males with gonadal dysfunction.

OBJECTIVE: To determine whether inhibin B levels are reflective of the etiology of gonadal dysfunction. DESIGN: Institutional study. SETTING: A tertiary care university-affiliated infertility clinic. PATIENT(S): Forty-four men: 16 with primary testicular failure, 10 with partial idiopathic hypogonadotropic hypogonadism (IHH), 8 with primary germ cell failure, one with iatrogenic hypogonadotropic hypogonadism, one with untreated Kallmann's syndrome, and 8 healthy fertile controls. INTERVENTION(S): Three individuals (one each with IHH, hypogonadotropic hypogonadism [HH], and Kallmann's syndrome) underwent treatment with human chorionic gonadotropin. MAIN OUTCOME MEASURE(S): Baseline serum inhibin B, FSH, LH, total testosterone and estradiol levels, and sperm concentrations were measured. RESULT(S): Serum inhibin B concentrations were significantly higher in fertile controls (255 +/- 59 pg/mL) than in men presenting with primary testicular failure (75 +/- 46 pg/mL, P<.0001) or in those presenting with primary germ cell failure (73 +/- 31 pg/mL, P<.0001). Inhibin B levels were also lower in males with partial IHH (187 +/- 112 pg/mL, P<.05). The patient with iatrogenic HH had a level of 184 pg/mL, whereas the patient with Kallmann's syndrome had nondetectable levels (<10 pg/mL). Serum inhibin B levels correlated positively with sperm concentration (P=.0001), and negatively with FSH levels (P=.01) and LH levels (P<.05). Human chorionic gonadotropin therapy altered inhibin B levels. CONCLUSION(S): Inhibin B plays an important role as an endocrine regulator of FSH secretion, whereas gonadotropins are involved in the regulation of inhibin B secretion.

Case-Control Studies↗
PubMed2000

Ethnic differences in post-menopausal plasma oestrogen levels: high oestrone levels in Japanese-American women despite low weight.

Breast cancer incidence in Japanese-American women is approaching that of US Whites. We investigated whether this shift is paralleled by similar post-menopausal plasma hormone levels in the two ethnic groups. We also included African-American and Latina women to further our understanding of possible ethnic differences in oestrogen metabolism. We measured androstenedione (A), oestrone (E1) and oestradiol (E2) in 30 Japanese-American, 39 non-Latina White ('White'), 66 African-American and 58 Latina women. The (age-adjusted) geometric mean E1 levels were 34 pg ml(-1) in Japanese-Americans, 28 pg ml(-1) in Whites, 35 pg ml(-1) in African-Americans and 31 pg ml(-1) in Latinas. After adjustment for body mass index, Japanese-Americans had the highest mean E1 value of all groups and this was statistically significantly greater than the value for Whites (P(t-test) = 0.05). The geometric mean A concentrations were also highest in Japanese-Americans. There was little ethnic difference in E2 levels. In conclusion, post-menopausal plasma oestrogen levels in Japanese-American women are at least as high as those in Whites.

Aged↗
PubMed2000

Effects of soy foods on ovarian function in premenopausal women.

It has been proposed that the high intake of soy foods among Asians may partly explain their lower rates of breast cancer, perhaps by lowering endogenous oestrogen levels, although this has been inadequately studied. Twenty healthy cycling premenopausal women (ten Asians and ten non-Asians) participated in a 7-month soy intervention study which was designed to investigate the effect of supplementation on ovarian function. Asian soy foods (tofu, soymilk, green soybean peas) in the amount of approximately 32 mg of isoflavones per day were added to the women's diets for three menstrual cycles. The women's baseline (two cycles) serum hormone levels were compared to levels during soy intervention (three cycles) and levels after intervention (two cycles). During the entire study period, subjects provided almost daily overnight urine samples and blood specimens during specified days of their menstrual cycles. The day of urinary luteinizing hormone (LH) peak was used as a marker for the day of ovulation. Knowledge of day of ovulation allowed comparison of hormone measurements at baseline to those obtained during intervention and recovery cycles with standardization of day of cycle. Soy intervention was associated with a statistically significant reduction in serum luteal oestradiol level (-9.3%, P < 0.05), but there were no significant changes in follicular phase oestradiol, follicular or luteal phase progesterone, sex hormone-binding globulin or menstrual cycle length. This significant reduction in luteal phase oestradiol was, however, observed only among Asian (-17.4%) but not among non-Asian (-1.2%) participants; urinary excretion of isoflavones was higher among Asians than non-Asians (29.2 vs 17.1 micromol day(-1), P= 0.16) during the intervention period. Thus, supplementation using traditional soy foods reduced serum oestradiol levels among Asian participants in this study. Differences in the type of soy products (i.e. traditional soy foods versus soy protein products), amount of isoflavones, and race/ethnicity of participants may have contributed to the divergent results. Larger soy intervention studies designed specifically to include participants of different race/ethnicities and using both traditional soy foods and soy protein products providing comparable doses of isoflavones are needed to definitively determine the effect of soy on ovarian function.

Adult↗
PubMed2000

Tumor stroma as the main source of inhibin production in ovarian epithelial tumors.

PROBLEM: Elevated serum inhibin levels have been found in ovarian cancer patients; however, the source of the elevated inhibin is uncertain. Previous studies of activin in human ovarian cancer suggest that activin may promote the growth of the tumor. The aims of this study were to examine the source of elevated inhibin from ovarian epithelial tumors (OETs) and to preliminarily investigate the role of the gonadotropin-inhibin/activin relationship in the development of OET. METHOD OF STUDY: The protein and mRNA expression of alpha and betaA subunits of inhibin/activin were examined by immunohistochemistry (IHC) and reverse transcription polymerase chain reaction (RT-PCR) in 120 OETs, including 30 benign cystadenomas, 30 borderline tumors, and 60 carcinomas. Stromal and epithelial cells were microdissected from 23 OETs to further examine the expression of alpha and betaA subunits by RT-PCR. Dimeric inhibin A and activin A production were measured by using the two-site ELISA from three OET cell lines in culture under treatment of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). RESULTS: betaA subunit was expressed in the epithelial component of 100% of the cystadenomas, in 80% of borderline tumors, and in 75% of the carcinomas, but not in tumor stroma. Inhibin alpha expression was not found in the epithelium of all OETs studied, but focal inhibin alpha immunoreactivity was seen in the tumor stroma (mainly luteinized stromal cells) in the majority of cases. Dimeric activin A was produced by all of the three OET cell lines with a 1.5-1.9-fold increment after FSH stimulation. However, activin A production was not augmented by LH treatment. No inhibin A was produced by the three OET cell lines with or without gonadotropin stimulation. CONCLUSIONS: The stroma of OET is the major source in the production of inhibin alpha (monomer). Dimeric inhibin A production may be the result of combined efforts of the tumor stroma (alpha subunit) and epithelium (betaA subunit). Cellular, compartmental expression of inhibin and activin subunits may play a role in the development of OET, although the mechanism remains undefined. The unopposed activin A production stimulated by FSH in OET cell lines suggests that activin production may represent one of the cellular mechanisms of growth promotion by FSH.

Activins↗
PubMed2000

Reproducibility studies and interlaboratory concordance for androgen assays in female plasma.

We conducted studies to determine the magnitude and sources of variability in androgen assay results and to identify laboratories capable of performing such assays for large epidemiological studies. We studied androstanediol (ADIOL), androstanediol glucuronide (ADIOL G), androstenedione (ADION), androsterone glucuronide (ANDRO G), androsterone sulfate (ANDRO S), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEA S), dihydrotestosterone (DHT), and testosterone (TESTO). A single sample of plasma was obtained from five postmenopausal women, five premenopausal women in the midfollicular phase of the menstrual cycle, and five women in the midluteal phase, divided into aliquots, and stored at -70 degrees. Four sets of two coded aliquots from each woman were then sent to participating labs for analysis at monthly intervals over 4 months. Using the logarithm of assay measurements, we estimated the components of variance and three measures of reproducibility. The usual coefficient of variation is a function of the components that are under the control of the laboratory. The intraclass correlation between measurements for a given individual is the proportion of the total variability that is associated with individuals. The minimum detectable relative difference is important to evaluate study feasibility. Results suggest that a single sample of ADIOL G, DHEA, DHEA S, and ANDRO G (with two lab replicates per sample) can be used to discriminate reliably among women in a given menstrual phase or menopausal status. The results for DHT, TESTO, ADION, and ANDRO S are more problematic and suggest that the present measurement techniques should be used with care, especially with midluteal phase women. The results for ADIOL suggest that this assay is not yet ready for use in epidemiological studies.

Adult↗
PubMed2000

Body size and prostate cancer: a population-based case-control study in China.

We conducted a population-based case-control study in China to investigate whether body size plays a role in prostate cancer etiology and whether it can explain the rapid increase in prostate cancer incidence rates in China. A total of 238 cases newly diagnosed with primary prostate cancer in Shanghai, China, during 1993-1995 were included in the study. Four hundred and seventy-one healthy control subjects were randomly selected from among residents of Shanghai and frequency-matched to cases on the basis of age. In-person interviews were conducted to elicit information on height, weight history, and other lifestyle factors. Waist and hip circumferences were measured at interview. Odds ratios (ORs) were used to measure the association between prostate cancer and anthropometric variables including height, weight, body mass index (BMI), waist, hip, and right upper arm circumferences, and waist-to-hip ratio (WHR; an indicator of abdominal adiposity). High levels of WHR were related to an excess risk, with men in the highest quartile (WHR > 0.92) having an almost 3-fold risk (OR, 2.71; 95% CI = 1.66-4.41; Ptrend = 0.0001) compared with men in the lowest quartile (WHR < 0.86). In contrast, men in the highest quartile of hip circumference (>97.4 cm) had a reduced risk (OR, 0.46; 95% CI = 0.29-0.74; Ptrend = 0.0002) relative to men in the lowest quartile (<86 cm). No association was found for height, usual adult weight, or preadult and usual adult BMI. Our results suggest that even in a very lean population (average BMI = 21.9), abdominal adiposity may be associated with an increased risk of clinical prostate cancer, pointing to a role of hormones in prostate cancer etiology. Additional research is needed to confirm these findings in prospective studies, especially in Western populations where abdominal obesity is much more common, and to clarify the underlying hormonal mechanisms involved.

Abdomen↗
PubMed1999

Urinary 2-hydroxyestrone/16alpha-hydroxyestrone ratio and risk of breast cancer in postmenopausal women.

BACKGROUND: It has been suggested that women who metabolize a larger proportion of their endogenous estrogen via the 16alpha-hydroxylation pathway may be at elevated risk of breast cancer compared with women who metabolize proportionally more estrogen via the 2-hydroxylation pathway. However, the supporting epidemiologic data are scant. Consequently, we compared the ratio of urinary 2-hydroxyestrone (2-OHE1) to 16alphahydroxyestrone (16alpha-OHE1) in postmenopausal women with breast cancer and in healthy control subjects. METHODS: Estrogen metabolites were measured in urine samples obtained from white women who had participated in a previous population-based, breast cancer case-control study at our institution. All P values are from two-sided tests. RESULTS: All of the urinary estrogens measured, with the exception of estriol, were higher in the 66 case patients than in the 76 control subjects. The mean value of urinary 2-OHE1 in case patients was 13.8% (P = .20) higher than that in control subjects, 16alpha-OHE1 was 12.1% (P = .23) higher, estrone was 20.9% higher (P = .14), and 17beta-estradiol was 12.0% higher (P = .36). The ratio of 2-OHE1 to 16alpha-OHE1 was 1.1% higher in the patients (P = .84), contrary to the hypothesis. Compared with women in the lowest third of the values for the ratio of urinary 2-OHE1 to 16alpha-OHE1, women in the highest third were at a nonstatistically significantly increased risk of breast cancer (odds ratio = 1.13; 95% confidence interval = 0.46-2.78), again contrary to the hypothesis. CONCLUSION: This study does not support the hypothesis that the ratio of the two hydroxylated metabolites (2-OHE1/16alpha-OHE1) is an important risk factor for breast cancer.

Aged↗