Introduction and objective: Manganese superoxide dismutase (MnSOD), an enzyme that catalyzes superoxide radical quenching, is hypothesized to protect against premature aging. A C47T transition in the MnSOD gene may affect the enzyme's distribution to the mitochondrion, a site of high oxidative stress. We examined the association between this polymorphism and survival.Methods: Individuals who donated a blood sample to the CLUE I and 11 campaigns in 1974 and 1989, respectively, and completed a food frequency questionnaire in 1989 (N = 6151) were included in the analysis. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated by Cox proportional hazards models. Mortality follow-up extended from 1989 to 2002.Results: MnSOD genotype distributions were 27% CC (wildtype homozygotes), 50% CT (heterozygotes) and 23% TT (variant homozygotes). TT and CT genotypes compared to the CC genotype were not associated with all-cause or cardiovascular disease mortality. A slight, but non-statistically significant higher risk of cancer mortality was observed for the CT (HR = 1.13, 95% CI: 0.86-1.49) and TT (HR = 1.24, 95% Cl: 0.90-1.70) genotypes compared to CC genotype (p-trend = 0.19).Conclusion: We did not observe an association between the C47T polymorphism in the MnSOD gene and survival. These null associations were not modified by fruit and vegetable intake, cigarette smoking status, or body mass index. (c) 2005 Elsevier Ireland Ltd. All rights reserved.
BACKGROUND. Biopsy-proven benign breast disease (BBD) is a risk factor for developing breast carcinoma; however, to the authors' knowledge, little is known regarding factors related to progression to carcinoma. A cohort study was conducted to examine the role of cyclooxygenase (COX) polymorphisms and nonsteroidal anti-inflammatory drugs (NSAIDs) in the progression of BBD to breast carcinoma.METHODS. Among participants in an ongoing cohort study, 1467 women under-went a breast biopsy for BBD. Of these women, 91 subsequently developed breast carcinoma. Medication data were collected in 1989 and in 1996. COX genotypes were determined using DNA extracted from blood specimens collected in 1989.RESULTS. A decrease in breast carcinoma risk was observed among women who reported using aspirin in 1989 (odds ratio [OR] of .46; 95% confidence interval [95% CI], .22-98) and in 1996 (OR of .47, 95% CI, .18-1.21). Furthermore, a higher frequency, dose, and longer duration of aspirin use were associated with a decrease in the odds of developing breast carcinoma. Overall, no association was observed between COX genotypes and the subsequent development of breast carcinoma. However, among women not using NSAIDs, one COX-2 polymorphism (rs2143416) was found to be significantly associated with the development of breast carcinoma.CONCLUSIONS. Findings front the current study, suggest that inflammation through COX-2 path may play a role in the progression of BBD to breast carcinoma and that aspirin may help to lower the risk of progression to breast carcinoma among women with BBD.
OBJECTIVE: Evidence links active cigarette smoking to cervical neoplasia, but much less is known about the role of passive smoking. Using a prospective cohort design, we examined personal cigarette smoking and household passive smoke exposure in relation to the risk of cervical neoplasia.METHODS: Cohorts were established based on data collected on the smoking status of all household members during private censuses of Washington County, Maryland in 1963 (n = 24,792) and 1975 (n = 26,381). Using the Washington County Cancer Registry, the occurrence of cervical neoplasia in the two cohorts was ascertained from 1963-1978 and from 1975-1994. Poisson regression models were fitted to estimate the relative risk of developing cervical neoplasia associated with active and passive smoking in both cohorts. The referent category for all comparisons was never smokers not exposed to passive smoking.RESULTS: The adjusted relative risk and 95% confidence limits for passive smoking was 2.1 (1.3, 3.3) in the 1963 cohort and 1.4 (0.8, 2.4) in the 1975 cohort. The adjusted relative risk and 95% confidence limits for current smoking were 2.6 (1.7, 4.1) and 1.7 (1.1, 2.6) in the 1963 and 1975 cohort, respectively.CONCLUSION: The associations were in the direction of increased risk for both passive smoking and current active smoking in both the 1963 and 1975 cohorts, but were stronger in the 1963 cohort. The results of this long-term, prospective cohort study corroborate the association between active cigarette smoking and cervical neoplasia and provide evidence that passive smoking is a risk factor for cervical neoplasia. (Obstet Gynecol 2005;105:174-81. (C) 2005 by The American College of Obstetricians and Gynecologists.).
BACKGROUND:Individuals with nonmelanoma skin cancer (NMSC) are at increased risk of developing subsequent cancers. Genetic predisposition to reduced DNA repair capacity may be an underlying susceptibility factor explaining the excess risk of malignancies. To test this hypothesis, a cohort study was conducted to examine the association between XPD Lys751Gln polymorphism and risk of a second primary cancer in individuals with NMSC.METHODS:A subgroup of 481 individuals with a history of NMSC who participated in the CLUE II community-based cohort was followed for the development of a second primary cancer. Blood specimens donated in 1989 were genotyped for the XPD Lys751Gln polymorphism using the 5' nuclease assay. Cox proportional regression with delayed entry was used to calculate the incidence rate ratio (IRR) and 95% confidence interval (95% CI) for risk of developing a second primary cancer according to XPD genotype. All statistical tests were two sided.RESULTS:Eighty individuals developed a second primary cancer. The most frequent occurring cancers were of the prostate (18%), lung (15%), and breast (15%). Persons with at least one Gln allele had an increased risk of a second primary cancer compared with the reference Lys/Lys genotype (adjusted IRR 2.22, 95% CI 1.30-3.76). When the reference category was limited to never smokers with the Lys/Lys genotype, the risk of developing a second primary cancer associated with having at least one Gln allele was increased >3-fold in both never smokers (IRR 3.93, 95% CI 1.36-11.36) and ever smokers (IRR 6.14, 95% CI 2.17-17.37).CONCLUSION:These findings suggest that individuals with NMSC who have the variant XPD Gln allele are at increased risk of developing a second primary cancer.
Nicotine replacement therapy (NRT) has added to the menu of options available to assist cigarette smokers in quit attempts, but cost remains a barrier to access. A quasi-experimental study was carried out to compare quit rates and continuous abstinence from smoking before (n=601) and after (n=311) free nicotine patches were offered to smokers who participated in the Washington County (Maryland) Health Department's "Stop Smoking for Life" group behavioral cessation program. After free NRT was offered, the quit rates upon completion of the program increased from 38% to 65% [difference 27%; 95% confidence limits (CL) 21%, 34%]. The difference in continuos abstinence from smoking between the two groups was no longer statistically significant after 6 months of follow-up, reflecting the more rapid rate of reversion to smoking that occurred during the 18-month follow-up period among the free NRT group who had quit [adjusted rate ratio (RR) 1.35; 95% CL 1.03, 1.78]. Enrollment during the first 18 months after free NRT was 37% greater than the program's first 18 months (P=.08). In conclusion, adding free nicotine patches to a smoking cessation program was associated with increased program enrollment and significantly increased short-term—but not long-term—quit rates. The rapid reversion to smoking in the group who received free nicotine patches could potentially be obviated if participants extend their use of nicotine patches after the free 6-week supply is exhausted.
N-acetyltransferases (NATs) are important catalytic enzymes that metabolize carcinogenic arylamines. NAT2 genotype might modify the role of cigarette smoking, a source of arylamine exposure, in breast cancer. We conducted a nested case-control study to investigate the association between NAT2 genotype, smoking and breast cancer risk among women (110 cases, 113 matched controls) from the CLUE II cohort in Washington County, MD. Compared to women with the slow acetylator genotype, the main effects odds ratios (OR) for NAT2 were 1.4 for the intermediate acetylator genotype (95% confidence limits (CL) 0.7, 2.7) and 3.6 for the homozygous rapid acetylator genotype (95% CL 1.1, 11.4) (P for trend=0.05). Smoking was associated in the direction of increased breast cancer risk in slow acetylators (e.g., >15 pack-years versus never smokers OR 2.0; 95% CL 0.7, 5.8) but not in rapid acetylators. These associations were not statistically significant in the total study population, but a statistically significant interaction between smoking and NAT2 acetylator status was present in postmenopausal women. The main effect of NAT2 in the direction of increased risk suggests that exposures to NAT2-activated carcinogens other than cigarette smoke may be important in this study population. The results for smoking were consistent with an inactivation role for NAT2 in breast cancer.
Higher intake of fruits, vegetables, and antioxidants may help protect against oxidative damage, thus lowering cancer and cardiovascular disease risk. This Washington County, Maryland, prospective study examined the association of fruit, vegetable, and antioxidant intake with all-cause, cancer, and cardiovascular disease death. CLUE participants who donated a blood sample in 1974 and 1989 and completed a food frequency questionnaire in 1989 (N = 6,151) were included in the analysis. Participants were followed to date of death or January 1, 2002. Compared with those in the bottom fifth, participants in the highest fifth of fruit and vegetable intake had a lower risk of all-cause (cases = 910; hazard ratio (HR) = 0.63, 95% confidence interval (CI): 0.51, 0.78; p-trend = 0.0004), cancer (cases = 307; HR = 0.65, 95% CI: 0.45, 0.93; p-trend = 0.08), and cardiovascular disease (cases = 225; HR = 0.76, 95% CI: 0.54, 1.06; p-trend = 0.15) mortality. Higher intake of cruciferous vegetables was associated with lower risk of all-cause mortality (HR = 0.74, 95% CI: 0.60, 0.91; p-trend = 0.04). No statistically significant associations were observed between dietary vitamin C, vitamin E, and beta-carotene intake and mortality. Overall, greater intake of fruits and vegetables was associated with lower risk of all-cause, cancer, and cardiovascular disease death. These findings support the general health recommendation to consume multiple servings of fruits and vegetables (5-9/day).
PURPOSE:A single nucleotide substitution of guanine to adenine (A) at base +316 in the ornithine decarboxylase (ODC) gene may be associated with greater ODC expression and increased tumor growth. ODC is induced by androgens in human prostatic epithelial cells, presumably via transcriptional activation of androgen receptor (AR) and also by nicotine. A nested case-control study was done to examine the association between this ODC genotype and prostate cancer risk, and whether it varies by AR gene CAG repeat length and smoking.MATERIALS AND METHODS:A total of 164 cases were matched to 2 controls each from a community based cohort. ODC and AR genotyping was performed using a TaqMan (PE Applied Biosystems, Foster City, California) based assay and automated fragment analysis, respectively. Conditional logistic regression was used to estimate the OR and 95% CI.RESULTS:The presence of the ODC A allele was not significantly associated with an increased risk of prostate cancer (OR 1.33, 95% CI 0.90 to 1.96). However, men who inherited at least 1 ODC A alleles and less than 22 AR CAG repeats were at twice the risk of prostate cancer compared with those with 2 guanine alleles and 22 or greater AR CAG repeats (OR 2.09, 95% CI 1.23 to 3.57). Smoking was associated with prostate cancer only in men carrying a least 1 ODC A allele (p interaction = 0.02).CONCLUSIONS:The ODC A allele was not associated with a statistically significant increased risk of prostate cancer. However, this association may vary according to the number of CAG repeats in the AR receptor and smoking status.
BACKGROUND. We evaluated the association of pre-diagnostic plasma concentration of C-reactive protein, a sensitive, but non-specific indicator of inflammation, with subsequent risk of prostate cancer.METHODS. Included were 264 histologically confirmed prostate cancer cases and 264 age-matched controls who were participants in the CLUE II cohort of Washington County, MD. C-reactive protein was measured using a high-sensitivity immunoturbidimetric assay. Odds ratios (ORs) and 95% confidence intervals (CI) were estimated from conditional logistic regression models by fourth of the C-reactive protein distribution with cutpoints based on the controls. The median concentrations from the lowest to highest fourth were 0.41,1.03,1.90, and 4.53 mg/L.RESULTS. Geometric mean plasma concentrations did not differ between the cases (1.24 +/- 2.94 mg/L) and controls (1.41 +/- 2.97 mg/L; P = 0.16). Compared to the bottom fourth, the ORs (95% CI) of prostate cancer were 1.29 (0.80 - 2.08), 0.98 (0.61 - 1.58), and 0.95 (0.57 - 1.58) for the second, third, and highest fourths (P trend = 0.66). These findings were unchanged after adjusting for body mass index (BMI) and cigarette smoking status or after excluding men with markedly elevated C-reactive protein, cases diagnosed during the first 2 years of follow-up, or controls who never had a PSA test. These findings did not differ by stage or grade of prostate cancer.CONCLUSIONS. Pre-diagnostic plasma concentration of C-reactive protein was not associated with subsequent risk of prostate cancer. (C) 2003 Wiley-Liss, Inc.
Background: Dehydroepiandrosterone (DHEA) and its analogs have potent chemoprotective actions in mouse skin tumorigenesis models. To assess this association in humans, we investigated the relationship of prediagnostic serum concentrations of DHEA and dehydroepiandrosterone sulfate (DHEAS) to the subsequent risk of developing malignant melanoma and squamous cell carcinoma of the skin in residents of Washington Country, Maryland, USA. Patients and Methods: In a nested case-control study, serum that had been stored in 1974 was thawed and assayed for DHEA and DHEAS for 23 cases of malignant melanoma and 28 cases of squamous cell carcinoma and 1-2 matched controls per case. Results: The mean serum concentrations of DHEA or DHEAS were similar in cases and controls. There were no statistically significant trends in the risk of developing malignant melanoma or squamous cell skin cancer by concentration of either steroid (all p-for-trends >0.30). Conclusion: The results of this study do not support the hypothesis that physiological concentrations of DHEA or DHEAS protect against skin cancer in humans.
Previous prospective studies have raised the possibility that the antioxidantproperties of carotenoids and vitamin E (alpha-tocopherol) and the role of vitamin A (retinol) in cellular differentiation may be associated with a reduced risk of subsequent breast cancer. To investigate the association between serum and plasma concentrations of retinol, retinyl palmitate, alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein, lycopene, total-carotenoids, alpha-tocopherol, and gamma-tocopherol with subsequent development of breast cancer, a nested case control study was conducted among female residents of Washington County, Maryland, who had donated blood for a serum bank in 1974 or 1989. Cases (n = 295) and controls (n = 295) were matched on age, race, menopausal status, and date of blood donation, and the analyses were stratified by cohort participation. Median concentrations of beta-carotene, lycopene, and total carotene were significantly lower in cases compared with controls in the 1974 cohort (13.1, 12.5, and 7.9% difference; P = 0.01, 0.04, and 0.04, respectively) and for lutein in the 1989 cohort (6.7% difference; P = 0.02). The risk of developing breast cancer in the highest fifth was approximately half of that of women in the lowest fifth for beta-carotene [odds ratio (OR) = 0.41; 95% confidence interval (CI) 0.22-0.79; P trend = 0.007], lycopene (OR = 0.55; 95% CI 0.29-1.06; P trend = 0.04), and total carotene (OR = 0.55; 95% CI 0.29-1.03; P trend = 0.02) in the 1974 cohort. There was generally a protective association for other micronutrients in both cohorts, although none reached statistical significance. The results suggest that carotenoids may protect against the development of breast cancer.