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Green tea is a commonly consumed beverage in China. Epidemiological and animal data suggest tea and tea polyphenols may be preventive against various cancers, including breast cancer. Catechol-O-methyltransferase (COMT) catalyzes catechol estrogens and tea polyphenols. The COMT rs4680 AA genotype leads to lower COMT activity, which may affect the relationship between green tea consumption and breast cancer risk. We evaluated whether regular green tea consumption was associated with breast cancer risk among 3454 incident cases and 3474 controls aged 20-74 y in a population-based case-control study conducted in Shanghai, China during 1996-2005. All participants were interviewed in person about green tea consumption habits, including age of initiation, duration of use, brew strength, and quantity of tea. Odds ratios (OR) and 95% CI were calculated for green tea consumption measures and adjusted for age and other confounding factors. Compared with nondrinkers, regular drinking of green tea was associated with a slightly decreased risk for breast cancer (OR, 0.88; 95% CI, 0.79-0.98). Among premenopausal women, reduced risk was observed for years of green tea drinking (P-trend = 0.02) and a dose-response relationship with the amount of tea consumed per month was also observed (P-trend = 0.046). COMT rs4680 genotypes did not have a modifying effect on the association of green tea intake with breast cancer risk. Drinking green tea may be weakly associated with a decreased risk of breast cancer.

Dietary red meat and animal fat have been linked to endometrial cancer (EC) risk, but the impact of bioavailable iron in animal-derived foods has been less well studied. Our objective was to investigate the effects of iron and fats on the risk of EC in a large, population-based, case-control study. The Shanghai Endometrial Cancer Study enrolled 1,204 EC cases and 1,212 controls who completed in-person interviews, including a food frequency questionnaire. Animal-derived iron and fat intakes were calculated from dietary intakes and food composition tables. Logistic regression models were used to evaluate independent and joint effects of iron and fat on EC risk. Animal-derived iron intake was positively associated with EC risk [adjusted OR = 1.9; 95% CI = 1.4-2.7, Ptrend < 0.01, highest vs. lowest quartile], predominantly after menopause (OR = 2.2; 95%CI = 1.4-3.4, Ptrend < 0.01) and in women with BMI ≥ 25 kg/m2(OR = 3.2; 95% CI = 1.4-7.5 in postmenopausal obese women, Ptrend < 0.01). Animal-derived fat was also associated with postmenopausal EC risk (OR = 1.7; 95% CI = 1.2-2.5, Ptrend < 0.01). Multiplicative interactions between animal-derived iron and BMI or animal-derived fat intake were not observed. Animal-derived iron intake is associated with increased risk of EC after menopause and among obese women. Avoidance of animal-derived (heme) iron may reduce the risk of EC in these women. [ABSTRACT FROM AUTHOR]

Background: Obesity is a major risk factor for endometrial cancer. Obesity, particularly central obesity, is considered as a systemic inflammatory condition and is related strongly to insulin resistance. C-reactive protein (CRP) is the most recognized biologic marker of chronic systematic inflammation, and it is conceivable that the CRP gene may work together with obesity in the development of endometrial cancer.Methods: On the basis of a population-based case-control study in a Chinese population, the authors obtained obesity measurements and data on 6 CRP single-nucleotide polymorphisms (SNPs) from 1046 patients with newly diagnosed endometrial cancer (cases) and from 1035 age frequency-matched controls. The association of the CRP SNPs with endometrial cancer risk and their modification on the association between obesity and endometrial cancer risk were evaluated.Results: Although CRP SNPs alone were not associated with endometrial cancer, the associations of endometrial cancer with central obesity, measured as the waist-to-hip ratio (WHR) and the waist circumference, seemed to be stronger in women who were homozygous for the major allele of reference SNP (rs)1130864 (cytidine [C]/C) than in women who had the C/thymidine (T) and T/T genotypes (interaction test: P = .013 for WHR; P = .083 for waist circumference). When the women were stratified further by menopausal status, the observed interactions persisted mainly in premenopausal women (interaction test: P < .001 for WHR; P = .002 for waist circumference).Conclusions: The current results suggested that, in the Chinese population that was studied, obesity-related insulin resistance and proinflammatory effects may play an important role in endometrial cancer risk, and these effects were modified significantly by the CRP SNP rs1130864. [ABSTRACT FROM AUTHOR]

Folate plays an important role in carcinogenesis. The enzyme 5,10-methylenetetrahydrofolate reductase (MTHFR), encoded by the MTHFR gene, is involved in this process. We investigated both the independent and joint effects of dietary folate and other methyl-related nutrients, as well as three polymorphisms of MTHFR (677C>T, 1298A>C, and 1793G>A), on endometrial cancer risk in a population-based case-control study. Between 1997 and 2003, 1,204 newly diagnosed endometrial cancer cases and 1,212 controls were recruited among women between the ages of 30 and 69 years in urban Shanghai, China. Information on dietary intake of folate and other methyl-related nutrients, including vitamin B2 (riboflavin), vitamin B6, vitamin B12, and methionine, was derived from a validated food frequency questionnaire. Genotyping was completed on 1,041 cases and 1,030 controls for MTHFR 677C>T (rs1801133), 1298A>C (rs1801131), and 1793 G>A (rs2274967) [corrected] Haplotype estimation of the three single-nucleotide polymorphisms was performed using PHASE software. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated to evaluate associations of nutrients, MTHFR genotypes, and haplotypes with endometrial cancer risk. A significant inverse association between dietary folate intake and endometrial cancer risk was observed among all subjects and non-B vitamin supplement users. The greatest reduction in endometrial cancer risk was observed among non-users of supplements in the highest quartile of dietary folate intake (OR, 0.5; 95% CI, 0.4-0.7) as compared with those in the lowest quartile. Dietary intake of folate cofactors (methionine, vitamin B2, vitamin B6, and vitamin B12) was not related to risk of endometrial cancer. No association was observed between endometrial cancer and the MTHFR 677C>T, 1298 A>C, and 1793G>A polymorphisms or derived haplotypes. Among non-users of supplements, however, the 1298C and 1793A alleles were associated with a lower risk of endometrial cancer among women with high dietary folate intake but related to a higher risk among those with low dietary folate intake (P(interaction) = 0.08 and 0.03, respectively). Further analysis showed that the lowest risk (OR, 0.6; 95% CI, 0.4-1.1) was among women with the 1298C allele and the highest intake of both folate and riboflavin (P(interaction) = 0.04). A similar association was observed for the 1793A allele (P(interaction) = 0.03). Our findings suggest that folate intake may decrease the risk of endometrial cancer and modify the effect of MTHFR polymorphisms on risk.

Objective: To assess the effect of tea consumption on the risk of endometrial cancer., Methods: In a population based case-control study conducted in urban Shanghai, face-to-face interviews were completed for 995 incidence cases aged 30 - 69 from January 1997 to December 2002 and 1087 controls that frequency-matched to cases on age. Unconditional logistic model was used for analysis., Results: An inverse association was observed in tea drinking and endometrial cancer risk. Compared to non-tea drinkers, regular tea drinkers had reduced risk of endometrial cancer (OR = 0.74; 95% CI: 0.54 - 1.01) in premenopausal women. Green tea had a protective effect on endometrial cancer among non-smoking or non-alcohol drinking women (OR = 0.77, P = 0.0199) and the ORs reduced with the increasing concentration of tea being served (P for trend = 0.0493). The multivariate ORs for drinking green tea < 7 times/week and >or= 7 times/week were 0.90 (95% CI: 0.53 - 1.54) and 0.76 (95% CI: 0.60 - 0.95) with the trend test of P = 0.0163., Conclusion: Tea drinking, with green tea in particurlar, seemed to have weak but inverse association with endometrial cancer risk, but this effect of protection might only limit to premenopausal women.

Purpose: The effects of estrogens are mediated primarily through estrogen receptor (ER) in breast tissue, and polymorphisms in the ER genes may alter the functions of these receptors. Polymorphisms in the ER-alpha gene have been reported to be associated with breast cancer risk. However, to our knowledge, no study has been published on the relation between ER-alpha gene polymorphisms and breast cancer survival., Experimental Design: To determine whether three common polymorphisms in the ER-alpha gene, PvuII, XbaI, and GT dinucleotide repeats are associated with breast cancer survival, we evaluated data from a cohort of 1,069 breast cancer patients who participated in the Shanghai Breast Cancer Study between 1996 and 1998. The median follow-up time for this cohort of women was 5.2 years., Results: No overall association was observed between ER gene polymorphisms and breast cancer survival. The genotype associations, however, were modified by ER status in breast cancer tissues. Comparing those with the PP genotype to the pp genotype of the PvuII polymorphism, the hazard ratios (HR) of dying were 3.30 [95% confidence interval (95% CI), 1.42-7.69] and 0.54 (95% CI, 0.24-1.23), respectively, for participants with ER-negative breast cancer and ER-positive breast cancer. Similarly, compared with those with no (GT)(23) alleles, carrying one or two (GT)(23) alleles of the GT repeat polymorphism was related to a HR of 1.48 (95% CI, 0.77-2.87) for ER-negative breast cancer and a HR of 0.25 (95% CI, 0.09-0.69) for ER-positive cancer. The effect of ER on breast cancer survival was also modified by genotypes of ER-alpha gene. Tests for multiplicative interaction were highly significant., Conclusions: These data suggest that the ER-alpha gene polymorphisms and ER status may have an interactive effect on breast cancer survival.

Objective: To evaluate the association of intake of soya food, a rich source of phytoestrogens, with the risk of endometrial cancer., Design: Population based case-control study, with detailed information on usual soya food intake over the past five years collected by face to face interview using a food frequency questionnaire., Setting: Urban Shanghai, China., Participants: 832 incident cases of endometrial cancer in women aged of 30 to 69 years diagnosed during 1997-2001 and identified from the Shanghai Cancer Registry; 846 control women frequency matched to cases on age and randomly selected from the Shanghai Residential Registry., Main Outcome Measures: Odds ratios for risk of endometrial cancer in women with different intakes of soya foods., Results: Regular consumption of soya foods, measured as amount of either soya protein or soya isoflavones, was inversely associated with the risk of endometrial cancer. Compared with women with the lowest quarter of intake, the adjusted odds ratio of endometrial cancer was reduced from 0.93 to 0.85 and 0.67 with increasing quarter of soya protein intake (P for trend 0.01). A similar inverse association was observed for soya isoflavones and soya fibre intake. The inverse association seemed to be more pronounced among women with high body mass index and waist:hip ratio., Conclusion: Regular intake of soya foods is associated with a reduced risk of endometrial cancer.

Background & Objective: Few studies on trend analysis in cancer incidence of the elderly people in China. The purpose of this study was to analyze time trends in urologic cancer incidence of the elderly people during the period 1973-1999 in Shanghai., Methods: The registered cancer cases were coded according to the 3-digit rubrics of the ninth revision of the International Classification of Diseases (ICD-9). Population estimates were based on periodic censuses, with age- and sex-specific annual estimates derived by linear inter- and extrapolation for the remaining years. The age-standardized rates adjusted to the world population were calculated for nine 3-year periods. Annual percent changes in incidence were estimated by means of a linear regression of the respective rates on the mid-point of calendar years, weighted by the number of cases., Results: During the 27-year period, cancers of prostate, bladder, and kidney have risen substantially among elderly male residents in Shanghai. The annual percent changes were 6.60%, 1.15%, and 5.30%, respectively. Among the elderly women, the rate of kidney cancer increased rapidly, with the annual percent change of 4.87%. The 75 years and older age group in women had substantial increases in incidence rates of bladder cancer., Conclusion: From 1973 to 1999, the incidence rates of the commonly urologic cancers increased substantially among the elderly residents in Shanghai, except for female bladder cancer.

The purpose of our study was to evaluate the association of menstrual and reproductive factors with the risk of endometrial cancer. In a population-based case-control study conducted in urban Shanghai, in-person interviews were completed for 833 women aged 30-69 years and an equal number of controls frequency-matched to cases by age. All cases were newly diagnosed with endometrial cancer between January 1, 1997 and December 31, 2001. The unconditional logistic regression model was employed to derive the adjusted odds ratios (ORs) of endometrial cancer and 95% confidence intervals (CIs) in relation to menstrual and reproductive factors. Earlier menarche age, particularly among premenopausal women, and later menopausal age were associated with an elevated risk of endometrial cancer. A clear dose-response relation between endometrial cancer risk and years of menstruation was observed (p for trend < 0.01). Compared to women ever having a pregnancy and women ever having had a live birth, respectively, nulligravity and nulliparity were both associated with a more than one-fold elevated risk of endometrial cancer. Both completed (OR = 3.02, 95% CI 1.10-8.32 for women never having a complete pregnancy) and incomplete pregnancy (OR = 0.69, 95%CI 0.55-0.87) conferred a protective effect against endometrial cancer, and the protective effect appeared to increase with total number of pregnancies (p for trend = 0.01). The effect of pregnancy on endometrial cancer remained unchanged with increasing time since the last pregnancy. Stillbirth and age at first pregnancy was unrelated to endometrial cancer risk. Our study suggests that prolonged menstruation was related to an increased risk of endometrial cancer while pregnancy, including induced abortion, reduced the risk of endometrial cancer., (Copyright 2003 Wiley-Liss, Inc.)

The effect of genetic polymorphisms in the TGF-beta1 gene at codon 10 (T+29C), codon 25 (G+74C), and the promoter region [C --> T at -509 from the transcription site, (C-509T)] on breast cancer survival was evaluated among a cohort of 1111 patients. The median follow-up time for the cohort was 5.17 years after cancer diagnosis. No DNA sequence variation at codon 25 of the TGF-beta1 gene was found, whereas polymorphisms in C-509T and T+29C were in strong linkage disequilibrium. Patients who carried the C allele of T+29C polymorphism had a reduced 5-year disease-free survival rate (75.6% for T/C, and 78.2% for C/C) compared with the T/T genotype (85.1%; P, 0.04); the age-adjusted hazard ratio was 1.5 (95% confidence interval, 1.1-2.2). Adjustment for clinical prognostic factors slightly attenuated the association (hazard ratio, 1.4, 95% confidence interval, 1.0-1.9). Our study suggests that genetic polymorphisms in the TGF-beta1 gene may play a role in breast cancer progression.

Cumulative evidence suggests a possible interaction of cooking methods with diet in the pathogenesis of breast cancer. Studies, however, are few and inconsistent. We evaluated the association of animal food intake and degree of browning by deep-frying with breast cancer risk in a population-based case-control study conducted during 1996-1998 among Chinese women in Shanghai, a population with a traditionally low risk of breast cancer. Included in the study were 1459 cases and 1556 age-frequency-matched controls with response rates of 91.1 and 90.3%, respectively. A validated food frequency questionnaire was used to obtain information on usual intake of animal foods and cooking oils and usual cooking methods. Increasing intake of red meat and freshwater fish was related to a moderately elevated risk of breast cancer risk. Stratified analyses showed that the positive association with red meat intake was primarily restricted to those who used deep-frying cooking method, particularly among those who deep-fried foods to well-done (odds ratio, 1.92; 95% confidence interval, 1.30-2.83 for the highest versus the lowest quintile; P for trend, 0.002). On the other hand, high intake of nonhydrogenated soybean cooking oil was related to a reduced risk of breast cancer among women who never deep-fried animal foods (odds ratio, 0.48; 95% confidence interval, 0.28-0.82 for the highest versus the lowest quintile; P for trend, 0.02). The positive association of breast cancer risk with red meat intake, especially well-done red meat, was more pronounced among women with a high body mass index than those without this risk factor, and the test for multiplicative interaction was statistically significant. This study suggests that high intake of deep-fried, well-done red meat may be associated with an increased risk of breast cancer, and the positive association may be modified by body weight. This study also suggests that nonhydrogenated soybean oil, if not used in high-temperature cooking, may be associated with a reduced risk of breast cancer.