bluuebunny/crossref_metadata_2025 huggingface dataset:
A Modified Host Cell Reactivation Assay to Measure DNA Repair Capacity for Removing 4-Aminobiphenyl Adducts: A Pilot Study of Bladder Cancer
Authors: Lin Jie , Kadlubar Fred F. , Spitz Margaret R. , Zhao Hua , Wu Xifeng
Published: September 2005

As DNA repair plays an important role in genetic susceptibility to bladder cancer, assessment of the DNA repair phenotype is critical for the molecular epidemiology of bladder cancer. In this study, we developed and applied an assay using the luciferase (luc) reporter gene in a host-cell reactivation assay to measure DNA repair capacity for DNA damage induced by 4-aminobiphenyl (4-ABP), a well-studied aromatic amine and a known bladder carcinogen. We observed a dose-response relationship for 4-ABP dosage and DNA repair capacity (luc activity). We then applied this assay to measure DNA repair capacity in a pilot study of 89 pairs of bladder cancer patients and healthy controls matched by age, gender, and ethnicity, and we found that DNA repair capacity was significantly lower in cases than in controls (13.0% versus 14.4%; P = 0.006). Poor DNA repair capacity was associated with 3.42-fold increased bladder cancer risk. Further analysis revealed that intermediate and low levels of DNA repair capacity increased bladder cancer risk to 3.43-fold and 4.97-fold, respectively, compared with individuals with the most efficient DNA repair capacity. Moreover, ever smokers with suboptimal DNA repair capacity exhibited a 6.06-fold increased risk compared with never smokers with normal DNA repair capacity. In conclusion, our results support the hypothesis that deficient DNA repair capacity for 4-ABP induced DNA damage and increases bladder cancer risk. Our assay provides a new tool to specifically quantify DNA repair capacity in bladder cancer studies and, therefore, contributes to our goal of further elucidating bladder carcinogenesis.
Sex Differences in Risk of Lung Cancer Associated with Methylene-tetrahydrofolate Reductase Polymorphisms
Authors: Shi Qiuling , Zhang Zhendong , Li Guojun , Pillow Patricia C. , Hernandez Ladia M. , Spitz Margaret R. , Wei Qingyi
Published: September 2005

Methylenetetrahydrofolate reductase (MTHFR) catalyzes the metabolism of folate and nucleotides needed for DNA synthesis and repair. Variations in MTHFR functions likely play roles in the etiology of lung cancer. The MTHFR gene has three nonsynonymous single nucleotide polymorphisms (i.e., C677T, A1298C, and G1793A) that have a minor allele frequency of >5%. We investigated the associations between the frequencies of MTHFR variant genotypes and risk of lung cancer in a hospital-based case-control study of 1,051 lung cancer patients and 1,141 cancer-free controls in a non-Hispanic White population. We found that compared with the MTHFR 1298AA genotype, the 1298CC genotype was associated with a significantly increased risk of lung cancer in women [(odds ratio (OR), 2.09; 95% confidence interval (95% CI), 1.32-3.29)] but not in men (OR, 0.95; 95% CI, 0.62-1.45). The MTHFR 677TT genotype was associated with a significantly decreased risk of lung cancer in women (OR, 0.60; 95% CI, 0.40-0.92) but not in men. No association was found between the MTHFR G1793A polymorphism and risk of lung cancer. Further analysis suggested evidence of gene-dietary interactions between the MTHFR C677T polymorphism and dietary intake of vitamin B6, vitamin B12, and methionine in women and evidence of gene-environment interactions between the MTHFR C677T and A1298C polymorphisms and tobacco smoking in men. In conclusion, the polymorphisms of MTHFR may contribute to the risk of lung cancer in non-Hispanic Whites and modify the risk associated with the dietary and environmental exposure in a sex-specific manner.
Family History of Cancer, Its Combination with Smoking and Drinking, and Risk of Squamous Cell Carcinoma of the Esophagus
Authors: Garavello Werner , Negri Eva , Talamini Renato , Levi Fabio , Zambon Paola , Dal Maso Luigino , Bosetti Cristina , Franceschi Silvia , La Vecchia Carlo
Published: September 2005

We analyzed the association between history of cancer in first-degree relatives and the risk of squamous cell carcinoma of the esophagus (SCCE) using data from three case-control studies conducted in Italy and Switzerland on 805 incident, histologically confirmed SCCE, and 3,461 hospital controls. The alcohol- and tobacco-adjusted odds ratio (OR) for a family history of esophageal cancer was 3.2 [95% confidence interval (CI), 1.7-6.2], and the OR was higher when the affected relative was a brother or was diagnosed at age <55 years. Compared to subjects without family history of esophageal cancer, noncurrent smokers, drinking <49 drinks per week, the OR was 2.9 (95% CI, 1.1-7.5) for family history alone, 15.5 (95% CI, 11.7-20.5) for current smokers drinking ≥49 drinks per week without family history of esophageal cancer, and 107.0 (95% CI, 13.0-880.2) for current smokers drinking ≥49 drinks per week who also had a family history of esophageal cancer. The risk of SCCE was also increased in subjects with a family history of cancer of the oral cavity/pharynx (OR, 3.7; 95% CI, 1.5-9.0) and stomach (OR, 2.0; 95% CI, 1.1-3.6), but not of other cancers, nor for a family history of any cancer (OR, 1.0; 95% CI, 0.8-1.4). These data show that, as for many other epithelial cancers, the risk of SCCE is increased in subjects with a family history of the disease, and that—in Western countries—avoidance of alcohol and tobacco is also the best way to prevent SCCE in subjects with a family history of the disease.
Associations among Circulating Sex Hormones, Insulin-Like Growth Factor, Lipids, and Mammographic Density in Postmenopausal Women
Authors: Aiello Erin J. , Tworoger Shelley S. , Yasui Yutaka , Stanczyk Frank Z. , Potter John , Ulrich Cornelia M. , Irwin Melinda , McTiernan Anne
Published: September 2005

Objective: Hormone therapy use has been positively associated with mammographic density in several studies. However, few studies have examined the association between endogenous hormone levels and mammographic density. Therefore, we evaluated the relationship of endogenous sex hormones, insulin-like growth factor (IGF), and lipids with mammographic density in 88 overweight, postmenopausal women not taking hormone therapy.

Methods: Percent density and dense area were evaluated as continuous measures using a computer-assisted program. We used multiple linear regression to evaluate the associations of sex hormones, IGF, and cholesterol with mammographic density, adjusting for confounders, including adiposity. We evaluated stratification by history of hormone therapy use (former versus never) and hormone therapy latency (<5 versus ≥5 years).

Results: Among former hormone therapy users, mammographic density was inversely associated with circulating levels of estrone (P = 0.01), estradiol (P = 0.003), free estradiol (P = 0.004), testosterone (P = 0.04), free testosterone (P = 0.02), androstenedione (P < 0.001), dehydroepiandrosterone (P = 0.01), and the ratio of IGF-I to its binding protein (IGF-I/IGFBP-3; P = 0.04). We found similar associations when we limited the analyses to women who had used hormone therapy within the past 5 years. We also noted positive associations of mammographic density with total cholesterol (P = 0.03) and low-density lipoprotein (P = 0.03) among former hormone therapy users. No associations were noted among women who had never used hormone therapy.

Conclusions: These results suggest that there is an inverse relationship between endogenous sex hormones and mammographic density in postmenopausal women among former users of hormone therapy. This is not consistent with the hormone therapy literature and should be confirmed in larger studies.
Absence of TP53 Codon 249 Mutations in Young Guinean Children with High Aflatoxin Exposure
Authors: Turner Paul C. , Sylla Abdoulaye , Kuang Shuang-Yuan , Marchant Clare L. , Diallo Mamadou S. , Hall Andrew J. , Groopman John D. , Wild Christopher P.
Published: September 2005

Infection with hepatitis viruses and chronic exposure to high levels of dietary aflatoxins are the major etiologic agents for hepatocellular carcinoma in west Africa. A challenge for the prevention of hepatocellular carcinoma in this region is that both hepatitis B virus and aflatoxin exposures start early in life; indeed, aflatoxin exposures can start in utero and continue unabated throughout childhood. A mutation in the TP53 tumor suppressor gene at codon 249 (TP53 Ser249 mutation) has been reported previously for hepatocellular carcinoma tumors and matched plasma DNA samples in individuals from areas with high aflatoxin exposure. We examined whether the TP53 Ser249 mutation could be observed in DNA found in plasma of young children (ages 2-5 years) from Guinea, west Africa, a region of high aflatoxin exposure. Plasma aflatoxin-albumin adducts were present in 119 of 124 (96%) of the children, geometric mean of positives 9.9 pg/mg albumin (95% confidence interval, 8.8-11.0 pg/mg). This is the level and prevalence of exposure observed previously in adults. Following PCR amplification of plasma-derived DNA and detection using mass spectrometry, none of the samples were found to contain the TP53 Ser249 mutation. Because ∼50% of the hepatocellular carcinomas in adults in west Africa have this specific TP53 Ser249 mutation, a lack of detection in samples from children ages <5 years may indicate that a window of opportunity for intervention exists that could be exploited to lower hepatocellular carcinoma risk.
Determinants of Prevalence, Acquisition, and Persistence of Human Papillomavirus in Healthy Mexican Military Men
Authors: Lajous Martín , Mueller Nancy , Cruz-Valdéz Aurelio , Aguilar Luis Victor , Franceschi Silvia , Hernández-Ávila Mauricio , Lazcano-Ponce Eduardo
Published: September 2005

Background: Human papillomavirus (HPV) infection is sexually transmitted, but the nature of the infection in males is poorly understood. We sought to identify determinants of HPV infection, acquisition, and persistence in 1,030 healthy military men in Mexico.

Methods: From July 2000 to July 2003, trained interviewers administered a questionnaire, conducted a genital examination, and collected samples. The presence of multiple HPV types in genital cells from the urethra, urethral meatus, scrotum, penile shaft, and coronal sulcus was evaluated. At baseline 1,030 participants and after 1-year follow-up 336 individuals were sampled using a highly sensitive DNA reverse blot strip assay.

Results: HPV prevalence was 44.6%; infection with high-risk types was observed in 34.8% participants and 51.1% were multiply infected. After 1-year follow-up, 165 men remained free of HPV, 68 cleared their infection, 45 acquired one, and 37 remained infected with the same HPV type. The period prevalence was 50.9%, the incidence rate was 17.9/1,000 men-months [95% confidence interval (95% CI), 13.0-23.9], clearance was 54%, and persistence was 29.4%. At baseline, the number of partners before age 20 years, a history of a sexually transmitted disease, and the presence of condilomas significantly increased the association with HPV infection. Having anal intercourse with males was associated with the risk of acquiring a HPV infection (odds ratio, 5.2; 95% CI, 1.2-23). The odds ratio for persistent infection was 0.10 (95% CI, 0-0.87) in men who reported being circumcised compared with those who did not.

Conclusions: High-risk sexual behavior increases the risk of HPV infection in males, whereas circumcision may lower the risk of persistence.
Significant Difference in the Trends of Female Breast Cancer Incidence Between Taiwanese and Caucasian Americans: Implications from Age-Period-Cohort Analysis
Authors: Shen Ying-Chun , Chang Chee-Jen , Hsu Chiun , Cheng Chia-Chi , Chiu Chang-Fang , Cheng Ann-Lii
Published: September 2005

Female invasive breast cancer (FIBC) in Taiwan is characterized by a striking recent increase of incidence and a relatively young median age (45-49 years) at diagnosis. The Westernization of lifestyle that is increasingly affecting younger generations of Taiwanese may have an important impact on this change. We compared epidemiologic data on FIBC in Taiwanese obtained from the Taiwan Cancer Registry with data for Caucasian Americans obtained from the database of the Surveillance, Epidemiology, and End Results Program for the period from 1980 to 1999. Age-specific incidence rates of FIBC were plotted by calendar year at diagnosis and by birth cohort for both populations. The individual effects of time period and birth cohort on the incidence trends of FIBC in both populations were evaluated using the age-period-cohort analysis. The incidence rate of FIBC was continuously increased in Taiwanese throughout the past 2 decades, whereas the increase of incidence was slowing down in Caucasian Americans. The incidence rates in Taiwanese women born after the 1960s were approaching that of Caucasian Americans. The age-period-cohort analysis showed a much stronger birth cohort effect on the incidence trend of FIBC in Taiwanese than in Caucasian Americans. This strong birth cohort effect corresponded to the Westernization of lifestyle in Taiwan since 1960. These findings indicate that a continued shift in the incidence and age distribution pattern of FIBC in Taiwanese toward that of Caucasian Americans should be anticipated.
Season, Sun, Sex, and Cervical Cancer
Authors: Hrushesky William J.M. , Sothern Robert B. , Rietveld Wop J. , Du Quiton Jovelyn , Boon Mathilde E.
Published: September 2005

Introduction: Sunlight's UV B component, a known cellular immunosupressant, carcinogen, and activator of viral infections, is generally seasonally available. Venereal human papillomavirus (HPV) transmission, at least in part, causes cervical cancer. We have previously inspected the monthly rates of venereal HPV infection and sunlight fluency in Southern Holland over 16 consecutive years. Both peak in August with at least 2-fold seasonality. The amount of available sunlight and the rate of Papanicolaou (Pap) smear screen–detected HPV are positively correlated. We now investigate whether premalignant and malignant cervical epithelial changes are also seasonal and related to seasonal sunlight fluency.

Methods: We have studied >900,000 consecutive, serially independent, interpretable screening Pap smears obtained by a single cervical cancer screening laboratory in Leiden, Holland, during a continuous 16-year span from 1983 through 1998. The average monthly rates of premalignant and malignant epithelial change were inspected and the annual patterns contrasted to the annual pattern of sunlight fluency at this global location and to monthly average HPV infection rate. Because HPV is venereally transmitted, Dutch seasonal sexual behavior was evaluated by assessment of the annual pattern of Dutch conception frequency as a competing cause for cervical cancer seasonality.

Results: (a) Twice as many premalignant and malignant epithelial changes were found among Pap smears obtained in the summer months, with an August peak concurrent with histopathologic evidence of HPV infection and sunlight fluency in Southern Holland. (b) Monthly sunlight fluency is correlated positively with both the monthly rates of Pap smear–detected cervical epithelial dysplasia and carcinomatous histopathology, as well as HPV. (c) Conception frequency, in this location, peaks in Spring not summer, and has a 4.8% annual amplitude.

Conclusions: (a) Cervical epithelial HPV infection and HPV-induced cervical epithelial dysplasia and carcinomatous change may each be novel sun exposure risks and thereby behaviorably avoidable. (b) Because screening Pap smears uncover many abnormalities that resolve spontaneously (false positives), these data may argue for screening and follow-up Pap smear examinations in seasons other than summer in the Northern Hemisphere, to diminish the false-positive smear rate. Global data are available to confirm and further test each of these conclusions.
Racial Differences in Premenopausal Endogenous Hormones
Authors: Pinheiro Simone P. , Holmes Michelle D. , Pollak Michael N. , Barbieri Robert L. , Hankinson Susan E.
Published: September 2005

Differences in breast cancer incidence across racial groups are well documented. African Americans have the highest rates of premenopausal breast cancer and Asians have lower breast cancer rates across all age groups. We hypothesized that levels of premenopausal endogenous hormones and growth factors, risk factors that have been predictive of breast cancer, would differ by race. Using a cross-sectional study design, we tested this hypothesis in the Nurses' Health Study II. We assayed estradiol, progesterone, prolactin, sex hormone binding globulin (SHBG), insulin-like growth factor-I (IGF-I), and IGFBP-3 in 111 African American and 111 Asian American women, matched to 111 Caucasian women on age, day of luteal phase, and day, time, and fasting status at blood collection. We analyzed the association between race and hormone levels using robust linear regression methods. In multivariate models, compared with Caucasians, African Americans had 18% higher levels of estradiol (P < 0.01), 17% higher free estradiol (P < 0.01), 11% lower SHBG (P = 0.05), 11% higher IGF-I (P < 0.01), 25% higher free IGF-I (P < 0.01), and 9% lower IGFBP-3 (P < 0.01) levels. In multivariate models, compared with Caucasian women, Asian Americans had 22% higher calculated free estradiol (P < 0.01), 31% lower SHBG (P < 0.01), and 25% higher free IGF-I (P < 0.01) levels. No racial differences were found in progesterone and prolactin levels. Our study showed hormone differences consistent with breast cancer risk between Caucasians and African Americans but inconsistent with breast cancer risk between Asian Americans and Caucasians. Further research is needed to explore differences across racial groups and the link between endogenous hormones and breast cancer risk.
Investigation of Genetic Variants of Genes of the Hemochromatosis Pathway and Their Role in Breast Cancer
Authors: Abraham Benny K. , Justenhoven Christina , Pesch Beate , Harth Volker , Weirich Gregor , Baisch Christian , Rabstein Sylvia , Ko Yon-Dschun , Brüning Thomas , Fischer Hans-Peter , Haas Susanne , Brod Sandra , Oberkanins Christian , Hamann Ute , Brauch Hiltrud ,   for the GENICA Network
Published: September 2005

Iron overload has been noticed as a feature of human breast cancer. Cellular iron uptake is regulated by the hemochromatosis and transferrin receptor system, mutations of which cause the iron storage disease hereditary hemochromatosis. To understand the role of hemochromatosis and transferrin receptor system mutations in breast cancer, we analyzed 19 sequence variations at HFE, TFR1, TFR2, and FPN1 and compared genotype frequencies between cases and controls in a German population. There were 688 breast cancer patients and 724 population-based and age-matched controls. For genotyping, we applied the Hemochromatosis Strip Assay and TaqMan allelic discrimination analyses. In addition to genotype frequencies, we established frequencies of compound genotypes. The frequencies of HFE at His63Asp, Ser65Cys, and Cys282Tyr, and of TFR1 at Ser142Gly minor alleles in this German population were 15.9%, 1.8%, 5.6%, and 46.0%, respectively. No rare variants at 15 more loci at HFE, TFR2, and FPN1 were observed in breast cancer patients. There were no significant differences of allele and genotype frequencies between cases and controls. Triple and quadruple compound genotypes at HFE_His63_Cys282-TFR1_Ser142Gly and HFE_His63_Ser65_Cys282-TFR1_Ser142Gly showed a nonsignificant increase in cases. Although limited by low numbers, an increased prevalence of the HFE Tyr282 minor allele was observed in breast cancer cases with a high number of affected lymph nodes (P = 0.032). Our data suggest that variants of the hemochromatosis-transferrin receptor system have no direct effect on the incidence of breast cancer in Germany. Possible effects on tumor progression and prognosis remain elusive.
Cyclooxygenase-2 Expression in FAP Patients Carrying Germ Line MYH Mutations
Authors: Frattini Milo , Carnevali Ileana , Signoroni Stefano , Balestra Debora , Moiraghi Maria Luisa , Radice Paolo , Varesco Liliana , Gismondi Viviana , Ballardini Giovanni , Sala Paola , Pierotti Marco A. , Pilotti Silvana , Bertario Lucio
Published: September 2005

Familial adenomatous polyposis (FAP) is an autosomal condition caused by inherited mutations in the adenomatous polyposis coli (APC) or in the MYH genes. Clinical trials have established that nonsteroidal anti-inflammatory drugs (NSAID) are effective in preventing the development as well as reducing the size and decreasing the number of adenomas in FAP patients. Our aim was to evaluate the cyclooxygenase-2 (COX-2) expression in surgical specimens from patients with no evidence of germ line APC mutations but carrying germ line MYH mutations. COX-2 expression was evaluated through immunohistochemical and mRNA analysis in carcinomas, adenomas, and healthy mucosa from six patients carrying germ line biallelic MYH mutations. A modulation of COX-2 expression from adenoma (lower level) to carcinoma (higher level) was observed in all patients by both immunohistochemical and mRNA analysis. Moreover, patients with MYH mutations showed a weak COX-2 expression in the whole colorectal mucosa, as for classic FAP patients carrying germ line APC mutations. All together, our data suggest that biallelic MYH patients might benefit from NSAID treatment, because in these patients COX-2 is overexpressed in the whole colorectal mucosa, a finding possibly related to the interplay between COX-2 and APC protein being the APC gene a common target of mutations in MYH patients.
Conditions Associated with Antibodies Against the Tumor-Associated Antigen MUC1 and Their Relationship to Risk for Ovarian Cancer
Authors: Cramer Daniel W. , Titus-Ernstoff Linda , McKolanis John R. , Welch William R. , Vitonis Allison F. , Berkowitz Ross S. , Finn Olivera J.
Published: September 2005

Many cancers, including ovarian, overexpress epithelial mucin (MUC1) and promote anti-MUC1 antibodies that may correlate with more favorable prognosis. By extension, risk for ovarian cancer might be reduced by preexisting MUC1-specific immunity. We measured anti-MUC1 antibodies in 705 control women, identified events predicting antibodies, and estimated ovarian cancer risk by comparing profiles of events generating antibodies in controls with those in 668 ovarian cancer cases. Factors predicting antibodies included oral contraceptive use, breast mastitis, bone fracture or osteoporosis, pelvic surgeries, nonuse of talc in genital hygiene, and to a lesser extent intrauterine device use and current smoking. There was a significant increase in the likelihood of having anti-MUC1 antibodies from 24.2% in women with 0 or 1 condition, to 51.4% in those with five or more conditions. By the same index of events, the risk for ovarian cancer was inversely associated with number of conditions predisposing to anti-MUC1 antibodies. Compared with having experienced 0 or 1 event, the adjusted risk for ovarian cancer decreased progressively with relative risks (and 95% confidence limits) of 0.69 (0.52-0.92), 0.64 (0.47-0.88), 0.49 (0.34-0.72), and 0.31 (0.16-0.61), respectively for women with two, three, four, and five or more events related to the presence of antibodies (Ptrend < 0.0001.) We conclude that several traditional and new risk factors for ovarian cancer may be explained by their ability to induce MUC1 immunity through exposure of MUC1 to immune recognition in the context of inflammatory or hormonal processes in various MUC1-positive tissues.
Sugar-Sweetened Soft Drink Consumption and Risk of Pancreatic Cancer in Two Prospective Cohorts
Authors: Schernhammer Eva S. , Hu Frank B. , Giovannucci Ed , Michaud Dominique S. , Colditz Graham A. , Stampfer Meir J. , Fuchs Charles S.
Published: September 2005

Background: A history of diabetes mellitus and a diet high in glycemic load are both potential risk factors for pancreatic cancer. Sugar-sweetened soft drinks are a prevalent source of readily absorbable sugars and have been associated with an increased risk of obesity and diabetes. We investigated whether higher consumption of sugar-sweetened soft drinks increases the risk of pancreatic cancer.

Methods: We examined the relation between consumption of sugar-sweetened soft drinks and the development of pancreatic cancer in the Nurses' Health Study and the Health Professionals Follow-up Study. Among 88,794 women and 49,364 men without cancer at baseline, we documented 379 cases of pancreatic cancer during up to 20 years of follow-up. Soft drink consumption was first assessed at baseline (1980 for the women, 1986 for the men) and updated periodically thereafter.

Results: Compared with participants who largely abstained from sugar-sweetened soft drinks, those who consumed more than three sugar-sweetened soft drinks weekly experienced overall a multivariate relative risk (RR) of pancreatic cancer of 1.13 [95% confidence interval (95% CI), 0.81-1.58; P for trend = 0.47]. Women in the highest category of sugar-sweetened soft drink intake did experience a significant increase in risk (RR, 1.57; 95% CI, 1.02-2.41; P for trend = 0.05), whereas there was no association between sweetened soft drink intake and pancreatic cancer among men. Among women, the risk associated with higher sugar-sweetened soft drink was limited to those with elevated body mass index (>25 kg/m2; RR, 1.89; 95% CI, 0.96-3.72) or with low physical activity (RR, 2.02; 95% CI, 1.06-3.85). In contrast, consumption of diet soft drinks was not associated with an elevated pancreatic cancer risk in either cohort.

Conclusion: Although soft drink consumption did not influence pancreatic cancer risk among men, consumption of sugar-sweetened soft drinks may be associated with a modest but significant increase in risk among women who have an underlying degree of insulin resistance.
A Comparison of Bilateral Breast Cancers in BRCA Carriers
Authors: Weitzel Jeffrey N. , Robson Mark , Pasini Barbara , Manoukian Siranoush , Stoppa-Lyonnet Dominique , Lynch Henry T. , McLennan Jane , Foulkes William D. , Wagner Teresa , Tung Nadine , Ghadirian Parviz , Olopade Olufunmilayo , Isaacs Claudine , Kim-Sing Charmaine , Møller Pal , Neuhausen Susan L. , Metcalfe Kelly , Sun Ping , Narod Steven A.
Published: September 2005

Background: Women with breast cancer and a BRCA mutation have a high risk of developing a contralateral breast cancer. It is generally believed that the two cancers represent independent events. However, the extent of concordance between the first and second tumors with respect to hormone receptor expression and other pathologic features is unknown.

Purpose: To determine the degree of concordance of estrogen receptor (ER) status, tumor grade, and histology in tumors from women with bilateral breast cancer and a BRCA mutation.

Subjects and Methods: Women with a history of bilateral invasive breast cancers were selected from an international registry of women with BRCA1 or BRCA2 mutations. Medical records were reviewed to document the characteristics of each cancer and the treatments received.

Results: Data were available for 286 women with bilateral breast cancer and a BRCA mutation (211 BRCA1; 75 BRCA2). The mean interval between first and second tumor was 5.1 years. The two tumors were concordant more often than expected for ER status (P < 0.0001) and for grade (P < 0.0001), but not for histology (P = 0.55). The ER status of the first tumor was highly predictive of the ER status of the second tumor (odds ratio, 8.7; 95% confidence interval, 3.5-21.5; P < 0.0001). Neither age, menopausal status, oophorectomy nor tamoxifen use was predictive of the ER status of the second tumor.

Conclusions: There is strong concordance in ER status and tumor grade between independent primary breast tumors in women with a BRCA mutation. The excess concordance may be due to common risk factors, genetic variation, or the existence of a preneoplastic lesion that is common to both tumors.
Cigarette Smoking and Risk of Non-Hodgkin's Lymphoma—A Population-Based Case-Control Study
Authors: Schöllkopf Claudia , Ekström Smedby Karin , Hjalgrim Henrik , Rostgaard Klaus , Gadeberg Ole , Roos Göran , Porwit-MacDonald Anna , Glimelius Bengt , Adami Hans-Olov , Melbye Mads
Published: September 2005

Background: Epidemiologic evidence of an association between tobacco smoking and non-Hodgkin's lymphoma has been conflicting. This may reflect that non-Hodgkin's lymphoma comprises several distinct disease entities with different etiologies, as some studies have indicated an association between smoking and follicular lymphoma.

Objective: To investigate the association between cigarette smoking and non-Hodgkin's lymphoma risk, overall and by subtype.

Methods: As part of a nationwide Danish-Swedish population-based case-control study, we interviewed 3,055 incident non-Hodgkin's lymphoma patients and 3,187 population controls. All lymphomas were uniformly classified according to the WHO classification. We used unconditional logistic regression to estimate adjusted odds ratios (OR) and 95% confidence intervals (95% CI) for the association between cigarette smoking and risk of non-Hodgkin's lymphoma.

Results: Cigarette smoking was not associated with the risk of non-Hodgkin's lymphoma overall (OR, 0.97; 95% CI, 0.87-1.08) nor with the major subgroups such as diffuse large B-cell lymphoma (OR, 0.94; 95% CI, 0.79-1.10), chronic lymphocytic leukemia (OR, 0.86; 95% CI, 0.72-1.02), or follicular lymphoma (OR, 1.03; 95% CI, 0.85-1.24). Female smokers were at a marginally increased risk of follicular lymphoma (OR, 1.41; 95% CI, 1.04-1.92). Men who had ever smoked had a significantly increased risk of T-cell lymphoma (OR, 1.67; 95% CI, 1.11-2.51). No dose-response association with cigarette smoking could be established for any lymphoma subgroup.

Conclusion: We found little evidence of an association between cigarette smoking and non-Hodgkin's lymphoma risk overall. Although increased risks of follicular lymphoma in female smokers and of T-cell lymphoma in male smokers were suggested, no dose-response relationship was observed, leaving limited support for causality.
Molecular Features of Adult Glioma Associated with Patient Race/Ethnicity, Age, and a Polymorphism inO6-Methylguanine-DNA-Methyltransferase
Authors: Wiencke John K. , Aldape Kenneth , McMillan Alex , Wiemels Joe , Moghadassi Michelle , Miike Rei , Kelsey Karl T. , Patoka Joe , Long Jeff , Wrensch Margaret
Published: September 2005

Background: Risk factors for adult glioma in the San Francisco Bay Area include well-known demographic features such as age and race/ethnicity, and our previous studies indicated that these characteristics are associated with the TP53 mutation status of patients' tumors. We enlarged our study to assess the relationships of risk factors with TP53 as well as epidermal growth factor receptor (EGFR) and murine double minute-2 (MDM2) gene amplification and expression and the germ line Leu84Phe polymorphism in the DNA repair protein O6-methylguanine-DNA-methyltransferase (MGMT). MGMT expression may depend on the TP53 status of cells.

Methods: Molecular analyses were carried out on 556 incident astrocytic tumors. MGMT genotype data were collected on germ line DNA from 260 of these cases.

Results: The tumor data confirm the inverse relationships between TP53 mutation and MDM2 (P = 0.04) or EGFR (P = 0.004) amplification and that patients whose tumors contain TP53 mutations are younger than those without (P < 0.001). Although there was little difference in age of patient by EGFR amplification or expression among glioblastoma multiforme cases, EGFR gene amplification was associated with much older age of onset of anaplastic astrocytoma; for example, EGFR-amplified anaplastic astrocytoma cases were on average 63 years old compared with 48 years for nonamplified cases (P = 0.005). An increased prevalence of TP53 mutation positive glioblastoma multiforme was noted among nonwhites (African American and Asian) compared with whites (Latino and non-Latino; P = 0.004). Carriers of the MGMT variant 84Phe allele were significantly less likely to have tumors with TP53 overexpression (odds ratio, 0.30; 95% confidence interval, 0.13-0.71) and somewhat less likely to have tumors with any TP53 mutation (odds ratio, 0.47; 95% confidence interval, 0.13-1.69) after adjusting for age, gender, and ethnicity. Interestingly, EGFR gene amplification and EGFR protein overexpression were also inversely associated with the MGMT 84Phe allele.

Conclusions: Our results are consistent with ethnic variation in glioma pathogenesis. The data on MGMT show that an inherited factor involving the repair of methylation and other alkylation damage, specifically to the O6 position of guanine, may be associated with the development of tumors that proceed in their development without TP53 mutations or accumulation of TP53 protein and possibly also those that do not involve amplification of the EGFR locus.
Etiologic and Other Factors Predicting Nevus-Associated Cutaneous Malignant Melanoma
Authors: Purdue Mark P. , From Lynn , Armstrong Bruce K. , Kricker Anne , Gallagher Richard P. , McLaughlin John R. , Klar Neil S. , Marrett Loraine D. ,   for the Genes, Environment, and Melanoma Study Group
Published: September 2005

Cutaneous malignant melanomas with histologic evidence of an associated nevus (N+) may have a different risk factor profile from that of melanomas without it (N−). To address this question, a case-only analysis of 932 people with cutaneous malignant melanoma was done to identify etiologic and other factors associated with N+ melanoma. Evidence of an associated nevus was found in 36% of melanomas. N+ melanomas were thinner (Ptrend = 0.0009) and more likely to be of the superficial spreading type than other types of melanoma. Subjects with N+ melanomas were younger (Ptrend < 0.0001) and reported a higher nevus density on their skin than subjects with N− melanomas [odds ratio (OR), 3.1; 95% confidence interval (CI), 1.6-6.0, for high nevus density versus no nevi]. Indicators of high accumulated sun exposure were less prevalent among subjects with N+ melanomas (OR, 0.3; 95% CI, 0.2-0.4, for melanoma location on the head and neck versus location on trunk; OR, 0.2; 95% CI, 0.1-0.4, for severe solar elastosis adjacent to the melanoma versus no elastosis; OR, 0.2; 95% CI, 0.1-0.4, for lentigo maligna melanoma subtype versus superficial spreading subtype). With the exception of solar elastosis and age, all of the aforementioned variables remained significantly associated with N+ melanomas in multivariate analyses. No associations with self-reported measures of sun exposure, sunburn, or pigmentation phenotype were apparent. Our findings provide some support for the hypothesis of etiologically separate pathways for melanoma, with N+ melanomas appearing less likely to develop in the presence of characteristics suggesting high accumulated sun exposure than N− melanomas. However, it is possible that high UV exposure causes involution of nevi, thus reducing the density of nevi in exposed skin and thereby the probability of N+ melanoma.
Body Mass and Mortality After Breast Cancer Diagnosis
Authors: Whiteman Maura K. , Hillis Susan D. , Curtis Kathryn M. , McDonald Jill A. , Wingo Phyllis A. , Marchbanks Polly A.
Published: September 2005

Obesity is an established risk factor for some breast cancers, but less is known about its effect on breast cancer prognosis. Understanding this relationship is important, given the increasing number of women diagnosed with breast cancer and the growing prevalence of obesity. We conducted a cohort analysis of 3,924 women ages 20 to 54 with incident breast cancer enrolled between 1980 and 1982 in the Cancer and Steroid Hormone study, a case-control study. Interview data were linked to survival information from the Surveillance, Epidemiology, and End Results Program. We used proportional hazards models to examine the relationship between breast cancer mortality and adult body mass index (BMI; calculated using usual adult weight), BMI at age 18, and weight change from age 18 to adulthood. Hazard ratios (HR) were adjusted for cancer stage and other factors. During a median follow-up of 14.6 years, 1,347 women died of breast cancer. Obese women (adult BMI ≥30.00) were significantly more likely than lean women (BMI ≤22.99) to die of breast cancer [HR, 1.34; 95% confidence interval (CI), 1.09-1.65]. Women with BMIs of 25.00-29.99 (HR, 1.25; 95% CI, 1.08-1.44) or 23.00-24.99 (HR, 1.20; 95% CI, 1.04-1.39) also had higher breast cancer mortality (P for trend <0.0001). BMI at age 18 and weight change were not associated with breast cancer mortality independently of other factors. Obesity could be a preventable risk factor for death among breast cancer patients. Further study is needed to determine how these findings might affect recommendations to reduce breast cancer mortality.
Increased Risk of Oral Leukoplakia and Cancer Among Mixed Tobacco Users Carrying XRCC1 Variant Haplotypes and Cancer Among Smokers Carrying Two Risk Genotypes: One on Each of Two Loci, GSTM3 and XRCC1 (Codon 280)
Authors: Majumder Mousumi , Sikdar Nilabja , Paul Ranjan Rashmi , Roy Bidyut
Published: September 2005

An individual's susceptibility to oral precancer and cancer depends not only on tobacco exposure but also on the genotypes/haplotypes at susceptible loci. In this hospital-based case-control study, 310 cancer patients, 197 leukoplakia patients, and 348 controls were studied to determine risk of the disease due to polymorphisms at three sites on XRCC1 and one site on XRCC3. Independently, variant genotypes on these loci did not modulate risk of leukoplakia and cancer except for the XRCC1 (codon 280) risk genotype in exclusive smokeless tobacco users with leukoplakia [odds ratios (OR), 2.4; 95% confidence intervals (CI), 1.0-5.7]. But variant haplotypes, containing one variant allele, on XRCC1 increased the risk of leukoplakia (OR, 1.3; 95% CI, 1.0-1.7). Among stratified samples, mixed tobacco users, carrying variant haplotypes, also had increased risk of both leukoplakia (OR, 2.2; 95% CI, 1.3-3.9) and cancer (OR, 1.9; 95% CI, 1.2-3.1). In a previous study on this population, it was shown that the GSTM3 (A/A) genotype increased the risk of oral leukoplakia and cancer among smokers, which has also been substantiated in this study with expanded sample sizes. The simultaneous presence of two risk genotypes in smokers, one on each of two loci, GSTM3 and XRCC1 (codon 280), increased the risk of cancer (OR, 2.4; 95% CI, 1.0-5.8). Again, smokers carrying two risk genotypes, one on each of two loci, GSTM3 and XRCC1 (codon 399), were also overrepresented in both leukoplakia and cancer populations (Ptrend = 0.02 and 0.04, respectively) but enhancement of risks were not observed; probably due to small sample sizes. Therefore, the presence of variant haplotypes on XRCC1 and two risk genotypes, one on each of two loci, GSTM3 and XRCC1, could be useful to determine the leukoplakias that might progress to cancer in a group of patients.
Endometrial Carcinoma Risks among Menopausal Estrogen plus Progestin and Unopposed Estrogen Users in a Cohort of Postmenopausal Women
Authors: Lacey James V. , Brinton Louise A. , Lubin Jay H. , Sherman Mark E. , Schatzkin Arthur , Schairer Catherine
Published: September 2005

Background: Because unopposed estrogen substantially increases endometrial carcinoma risk, estrogen plus progestin is one menopausal hormone therapy formulation for women who have not had a hysterectomy. However, endometrial carcinoma risks among estrogen plus progestin users and among former unopposed estrogen users are not firmly established.

Methods: We evaluated endometrial carcinoma risks associated with estrogen plus progestin and unopposed estrogen therapies in 30,379 postmenopausal Breast Cancer Detection Demonstration Project follow-up study participants. We ascertained hormone therapy use and other risk factors during telephone interviews and mailed questionnaires between 1979 and 1998. We identified 541 endometrial carcinomas via self-report, medical records, the National Death Index, and state cancer registries. Poisson regression generated time-dependent rate ratios (RR) and 95% confidence intervals (95% CI).

Results: Endometrial carcinoma was significantly associated with estrogen plus progestin only use (n = 68 cancers; RR, 2.6; 95% CI, 1.9-3.5), including both sequential (progestin <15 days per cycle; n = 32 cancers; RR, 3.0; 95% CI, 2.0-4.6) and continuous (progestin at least 15 days per cycle; n = 15 cancers; RR, 2.3; 95% CI, 1.3-4.0) regimens. The RR increased by 0.38 (95% CI, 0.20-0.64) per year of estrogen plus progestin use, and RRs increased with increasing duration of use for both regimens. The strong association with unopposed estrogen use declined after cessation but remained significantly elevated ≥10 years after last use (RR, 1.5; 95% CI, 1.0-2.1).

Conclusions: Both estrogen plus progestin regimens significantly increased endometrial carcinoma risk in this study. Risks among unopposed estrogen users remained elevated long after last use. The prospect that all estrogen plus progestin regimens increase endometrial carcinoma risk deserves continued research.
Ethnic Difference in Daycare Attendance, Early Infections, and Risk of Childhood Acute Lymphoblastic Leukemia
Authors: Ma Xiaomei , Buffler Patricia A. , Wiemels Joseph L. , Selvin Steve , Metayer Catherine , Loh Mignon , Does Monique B. , Wiencke John K.
Published: September 2005

A role for infectious agents has been proposed in the etiology of childhood acute lymphoblastic leukemia (ALL), particularly for common ALL (c-ALL; ALL diagnosed in children ages 2-5 years and expressing CD10 and CD19 surface antigens). We evaluated the possible etiologic role of daycare attendance (a proxy measure for exposure to infectious agents) and infections during infancy in the Northern California Childhood Leukemia Study. A total of 294 incident ALL cases (ages 1-14 years) and 376 individually matched controls were included in this analysis. In non-Hispanic White children, daycare attendance measured by child-hours was associated with a significantly reduced risk of ALL. Compared with children who did not attend any daycare, the odds ratio (OR) for those who had >5,000 child-hours during infancy was 0.42 [95% confidence interval (95% CI), 0.18-0.99] for ALL and 0.33 (95% CI, 0.11-1.01) for c-ALL. Test for trend is also significant, which supports a dose-response relationship. The magnitude of effect associated with the same number of child-hours was stronger for daycare attendance during infancy than for daycare attendance before diagnosis. In addition, self-reported ear infection during infancy was associated with a significantly reduced risk of c-ALL (OR, 0.32; 95% CI, 0.14-0.74) in non-Hispanic White children. In Hispanic children, no association was observed among daycare attendance, early infections, and risk of childhood ALL or c-ALL. These results offer indirect yet strong support for the infectious disease hypothesis in the etiology of ALL in non-Hispanic White children and highlight an important ethnic difference.
Allergies and the Risk of Pancreatic Cancer: A Meta-analysis with Review of Epidemiology and Biological Mechanisms
Authors: Gandini Sara , Lowenfels Albert B. , Jaffee Elizabeth M. , Armstrong Todd D. , Maisonneuve Patrick
Published: September 2005

Previous reports suggest that allergic disorders may protect against various types of cancer, but the association between history of allergy and pancreatic cancer risk has not been well studied. We did a systematic review and meta-analysis of published studies to evaluate the association of any type, and specific types, of allergy and the risk of pancreatic cancer. We did a comprehensive literature search using MEDLINE, PUBMED, and the ISI Web of Science databases to identify potential relevant case-control and cohort studies. Pooled relative risks (RR) and 95% confidence intervals (95% CI) were calculated using the fixed- and random-effects model. Fourteen population-based studies (4 cohort and 10 case-control studies) with a total of 3,040 pancreatic cancer cases fulfilled our inclusion criteria. A history of allergy was associated with a reduced risk of pancreatic cancer (RR, 0.82; 95% CI, 0.68-0.99). The risk reduction was stronger for allergies related to atopy (RR, 0.71; 95% CI, 0.64-0.80), but not for asthma (RR, 1.01; 95% CI, 0.77-1.31). There was no association between allergies related to food or drugs and pancreatic cancer (RR, 1.08; 95% CI, 0.74-1.58). Overall, there was no evidence of publication bias. Allergies, in particular those related to atopy, seem to be associated with a decreased risk of pancreatic cancer. The hyperactive immune system of allergic individuals may, therefore, in some way lead to increased surveillance and protect against pancreatic cancer development.
5,10-Methylenetetrahydrofolate Reductase 677 and 1298 Polymorphisms, Folate Intake, and Microsatellite Instability in Colon Cancer
Authors: Eaton Allison M. , Sandler Robert , Carethers John M. , Millikan Robert C. , Galanko Joseph , Keku Temitope O.
Published: September 2005

The 5,10-methylenetetrahydrofolate reductase (MTHFR) gene plays a critical role in folate metabolism. Studies on the association between MTHFR polymorphisms and length changes in short tandem repeat DNA sequences [microsatellite instability (MSI)] are inconsistent. Using data from colon cancer cases (n = 503) enrolled as part of an existing population-based case-control study, we investigated the association between MTHFR 677 and MTHFR 1298 polymorphisms and MSI. We also examined whether the association was modified by folate intake. Participants were case subjects enrolled as part of the North Carolina Colon Cancer Study. Consenting cases provided information about lifestyle and diet during in-home interviews as well as blood specimens and permission to obtain tumor blocks. DNA from normal and tumor tissue sections was used to determine microsatellite status (MSI). Tumors were classified as MSI if two or more microsatellite markers (BAT25, BAT26, D5S346, D2S123, and D17S250) had changes in the number of DNA sequence repeats compared with matched nontumor tissue. Tumors with one positive marker (MSI-low) or no positive markers (microsatellite stable) were grouped together as non-MSI tumors (microsatellite stable). MTHFR 677 and MTHFR 1298 genotypes were determined by real-time PCR using the 5′ exonuclease (Taqman) assay. Logistic regression was used to calculate odds ratio (OR) and 95% confidence intervals (95% CI). MSI was more common in proximal tumors (OR, 3.8; 95% CI, 1.7-8.4) and in current smokers (OR, 4.0; 95% CI, 1.6-9.7). Compared with MTHFR 677 CC referent, MTHFR 677 CT/TT genotype was inversely associated with MSI among White cases (OR, 0.36; 95% CI, 0.16-0.81) but not significant among African Americans. Although not statistically significant, a similar inverse association was observed between MTHFR 677 CT/TT genotype and MSI among the entire case subjects (OR, 0.54; 95% CI, 0.26-1.10). Among those with adequate folate intake (>400 μg total folate), we found strong inverse associations between combined MTHFR genotypes and MSI (677 CC + 1298 AC/CC, OR, 0.09; 95% CI, 0.01-0.59; 677 CT/TT + 1298 AA, OR, 0.13; 95% CI, 0.02-0.85) compared with the combined wild-type genotypes (677 CC + 1298 AA). This protective effect was not evident among those with low folate (<400 μg total folate) intake. Our results suggest that MTHFR variant genotypes are associated with reduced risk of MSI tumors under conditions of adequate folate intake, although the data are imprecise due to small numbers. These results indicate that the relationship between MTHFR genotypes and MSI is influenced by folate status.