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PURPOSE: Despite the overlap between the clinical symptoms/sequelae of polycystic ovarian syndrome (PCOS) and many known reproductive risk factors for breast cancer, the relationship between PCOS and breast cancer remains unclear, possibly because of the complex heterogeneity and challenges in diagnosing PCOS over time. We hypothesized that PCOS, specific PCOS-related symptoms/sequelae, or clusters of PCOS-related symptoms/sequelae may be differentially associated with pre- versus postmenopausal breast cancer risk. MATERIALS AND METHODS: Cases were 1,508 women newly diagnosed with a first primary in situ or invasive breast, and the 1,556 population-based controls were frequency-matched by age. RESULTS: History of physician-diagnosed PCOS was reported by 2.2 % (n = 67), among whom oral contraceptive (OC) use, irregular menstruation, and infertility due to ovulatory dysfunction were common. Using unconditional logistic regression, adjusted odds ratios (95 % CI) for PCOS were increased for premenopausal [2.74 (1.13, 6.63)], but not postmenopausal breast cancer [0.87 (0.44, 1.71)]. We used cluster analysis to investigate whether risk among all women varied by PCOS-related symptoms/sequelae, such as reproductive irregularities, OC use, and components of insulin resistance. In the cluster analysis, odds ratios were elevated among premenopausal women who had a history of OC use and no ovulatory dysfunction [1.39 (1.03, 1.88)], compared to those with fewer number of PCOS-related symptoms/sequelae. CONCLUSION: PCOS and associated PCOS-related symptoms/sequelae including OC use may play a role in the development of premenopausal breast cancer. Our findings require confirmation in studies with a larger number of premenopausal women with systematically applied diagnostic criteria for PCOS.
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Neoplasias de la Mama/epidemiología , Resistencia a la Insulina , Síndrome del Ovario Poliquístico/epidemiología , Adulto , Anciano , Neoplasias de la Mama/etiología , Estudios de Casos y Controles , Femenino , Humanos , Modelos Logísticos , Persona de Mediana Edad , Oportunidad Relativa , Síndrome del Ovario Poliquístico/complicaciones , Factores de RiesgoRESUMEN
The ability to establish genetic risk models is critical for early identification and optimal treatment of breast cancer. For such a model to gain clinical utility, more variants must be identified beyond those discovered in previous genome-wide association studies (GWAS). This is especially true for women at high risk because of family history, but without BRCA1/2 mutations. This study incorporates three datasets in a GWAS analysis of women with Ashkenazi Jewish (AJ) homogeneous ancestry. Two independent discovery cohorts comprised 239 and 238 AJ women with invasive breast cancer or preinvasive ductal carcinoma in situ and strong family histories of breast cancer, but lacking the three BRCA1/2 founder mutations, along with 294 and 230 AJ controls, respectively. An independent, third cohort of 203 AJ cases with familial breast cancer history and 263 healthy controls of AJ women was used for validation. A total of 19 SNPs were identified as associated with familial breast cancer risk in AJ women. Among these SNPs, 13 were identified from a panel of 109 discovery SNPs, including an FGFR2 haplotype. In addition, six previously identified breast cancer GWAS SNPs were confirmed in this population. Seven of the 19 markers were significant in a multivariate predictive model of familial breast cancer in AJ women, three novel SNPs [rs17663555(5q13.2), rs566164(6q21), and rs11075884(16q22.2)], the FGFR2 haplotype, and three previously published SNPs [rs13387042(2q35), rs2046210(ESR1), and rs3112612(TOX3)], yielding moderate predictive power with an area under the curve (AUC) of the ROC (receiver-operator characteristic curve) of 0.74. Population-specific genetic variants in addition to variants shared with populations of European ancestry may improve breast cancer risk prediction among AJ women from high-risk families without founder BRCA1/2 mutations.
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Neoplasias de la Mama/genética , Carcinoma Ductal de Mama/genética , Genética de Población , Estudio de Asociación del Genoma Completo , Judíos/genética , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Área Bajo la Curva , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/etnología , Carcinoma Ductal de Mama/etnología , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Genotipo , Haplotipos , Humanos , Persona de Mediana Edad , Mutación , Curva ROC , Medición de RiesgoRESUMEN
BACKGROUND: Telomeres at the ends of eukaryotic chromosomes play a critical role in maintaining the integrity and stability of the genome and participate in the initiation of DNA damage/repair responses. METHODS: We performed a case-control study to evaluate the role of three SNPs (TERT-07, TERT-54 and POT1-03) in telomere maintenance genes previously found to be significantly associated with breast cancer risk. We used sister-sets obtained from the New York site of the Breast Cancer Family Registry (BCFR). Among the 313 sister-sets, there were 333 breast cancer cases and 409 unaffected sisters who were evaluated in the current study. We separately applied conditional logistic regression and generalized estimating equations (GEE) models to evaluate associations between the three SNPs and breast cancer risk within sister-sets. We examined the associations between genotype, covariates and telomere length among unaffected sisters using a GEE model. RESULTS: We found no significant associations between the three SNPs in telomere maintenance genes and breast cancer risk by both conditional logistic regression and GEE models, nor were these SNPs significantly related to telomere length. Among unaffected sisters, shortened telomeres were statistically significantly correlated with never hormone replacement therapy (HRT) use. Increased duration of HRT use was significantly associated with reduced telomere length. The means of telomere length were 0.77 (SD = 0.35) for never HRT use, 0.67 (SD = 0.29) for HRT use < 5 yrs and 0.59 (SD = 0.24) for HRT use ≥ 5 yrs after adjusting for age of blood donation and race and ethnicity. CONCLUSIONS: We found that exogenous hormonal exposure was inversely associated with telomere length. No significant associations between genetic variants and telomere length or breast cancer risk were observed. These findings provide initial evidence to understand hormonal exposure in the regulation of telomere length and breast cancer risk but need replication in prospective studies.
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Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Predisposición Genética a la Enfermedad , Variación Genética , Homeostasis del Telómero/genética , Telómero/genética , Estudios de Casos y Controles , Familia , Femenino , Humanos , Modelos Logísticos , Persona de Mediana Edad , New York , Sistema de Registros , Factores de Riesgo , HermanosRESUMEN
Estrogen and endocrine-disrupting chemicals (EDCs) that are associated with several health outcomes have been found in hair products. We evaluated the proportion, frequency, duration, and content of hair products in a racially/ethnically diverse population. We recruited n = 301 African-American, African-Caribbean, Hispanic, and white women from the New York metropolitan area. We collected data on hair oil, lotion, leave-in conditioner, root stimulator, perm, and other product use. Estrogen and EDC information was collected from commonly used hair products' labels (used by >3% of population). African-American and African-Caribbean women were more likely to use all types of hair products compared to white women (P < 0.0001). Among hair product users, frequency varied significantly by race/ethnicity, but not duration. More African-Americans (49.4%) and African-Caribbeans (26.4%) used products containing placenta or EDCs compared to whites (7.7%). African-American and African-Caribbean women were more likely to be exposed to hormonally-active chemicals in hair products.
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Exposición a Riesgos Ambientales/efectos adversos , Contaminantes Ambientales/efectos adversos , Etnicidad/estadística & datos numéricos , Preparaciones para el Cabello/efectos adversos , Disparidades en el Estado de Salud , Grupos Raciales/estadística & datos numéricos , Adulto , Negro o Afroamericano/estadística & datos numéricos , Estrógenos/efectos adversos , Femenino , Preparaciones para el Cabello/toxicidad , Hispánicos o Latinos/estadística & datos numéricos , Humanos , New York , Factores de Riesgo , Estadística como Asunto , Salud de la MujerRESUMEN
PURPOSE: Previous studies suggest that hair products containing endocrine disrupting chemicals could alter puberty. We evaluated the association between childhood hair product use and age at menarche in a racially diverse study population. METHODS: We recruited 300 African-American, African-Caribbean, Hispanic, and white women from the New York City metropolitan area who were between 18-77 years of age. Data were collected retrospectively on hair oil, lotion, leave-in conditioner, perm, and other types of hair products used before age 13. Recalled age at menarche ranged from 8 to 19 years. We used multivariable binomial regression to evaluate the association between hair product use and age at menarche (<12 vs. ≥12), adjusting for potential confounders. RESULTS: African-Americans were more likely to use hair products and reached menarche earlier than other racial/ethnic groups. Women reporting childhood hair oil use had a risk ratio of 1.4 (95% confidence interval [CI]: 1.1-1.9) for earlier menarche, adjusting for race/ethnicity and year of birth. Hair perm users had an increased risk for earlier menarche (adjusted risk ratio = 1.4, 95% CI: 1.1-1.8). Other types of hair products assessed in this study were not associated with earlier menarche. CONCLUSIONS: Childhood hair oil and perm use were associated with earlier menarche. If replicated, these results suggest that hair product use may be important to measure in evaluating earlier age at menarche.
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Negro o Afroamericano/estadística & datos numéricos , Preparaciones para el Cabello , Menarquia , Adolescente , Adulto , Edad de Inicio , Anciano , Niño , Femenino , Humanos , Entrevistas como Asunto , Menarquia/etnología , Persona de Mediana Edad , Ciudad de Nueva York , Proyectos Piloto , Población Urbana , Adulto JovenRESUMEN
INTRODUCTION: Selecting women affected with breast cancer who are most likely to carry a germline mutation in BRCA1 and applying the most appropriate test methodology remains challenging for cancer genetics services. We sought to test the value of selecting women for BRCA1 mutation testing on the basis of family history and/or breast tumour morphology criteria as well as the value of testing for large genomic alterations in BRCA1. METHODS: We studied women participating in the Breast Cancer Family Registry (BCFR), recruited via population-based sampling, who had been diagnosed with breast cancer before the age of 40 years who had a strong family history of breast or ovarian cancer (n = 187) and/or a first primary breast tumour with morphological features consistent with carrying a BRCA1 germline mutation (n = 133; 37 met both criteria). An additional 184 women diagnosed before the age of 40 years who had a strong family history of breast or ovarian cancer and who were not known to carry a germline BRCA1 mutation were selected from among women who had been recruited into the BCFR from clinical genetics services. These 467 women had been screened for BRCA1 germline mutations, and we expanded this testing to include a screen for large genomic BRCA1 alterations using Multiplex Ligation-dependent Probe Amplification. RESULTS: Twelve large genomic BRCA1 alterations were identified, including 10 (4%) of the 283 women selected from among the population-based sample. In total, 18 (12%), 18 (19%) and 16 (43%) BRCA1 mutations were identified in the population-based groups selected on the basis of family history only (n = 150), the group selected on the basis of tumour morphology only (n = 96) and meeting both criteria (n = 37), respectively. CONCLUSIONS: Large genomic alterations accounted for 19% of all BRCA1 mutations identified. This study emphasises the value of combining information about family history, age at diagnosis and tumour morphology when selecting women for germline BRCA1 mutation testing as well as including a screen for large genomic alterations.
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Neoplasias de la Mama/genética , Genes BRCA1 , Mutación , Adulto , Edad de Inicio , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/patología , Femenino , Genes BRCA2 , Predisposición Genética a la Enfermedad , Genoma Humano , Humanos , Persona de Mediana Edad , Sistema de RegistrosRESUMEN
The impact of treatment on subsequent fertility and the safety of childbearing are major complicating factors for young women diagnosed with breast cancer. As national data indicate women are postponing first pregnancy to older ages; therefore, many young patients are seeking clinical guidance regarding the safety of conception and treatment options that may not prevent subsequent pregnancy. Newly developed chemotherapy protocols of brief duration have improved life expectancy enabling some women to consider childbearing. This study was conducted to compare prognosis among breast cancer patients with and without a subsequent pregnancy. Medical record review of female members of a Northern California prepaid health care plan enabled the identification of 107 women with one or more subsequent pregnancies and 344 cases without a pregnancy, who were diagnosed between 1968 and 1995. Sets were matched on age, year and stage at diagnosis, months of survival and recurrence status at conception. Among the matched sets, neither risk of recurrence nor death differed significantly by subsequent pregnancy history during an average 12 years of follow-up (adjusted hazard ratio [HR] recurrence: 1.2 [0.8, 2.0]; adjusted HR death: 1.0 [0.6, 1.9]). Women interested in preserving their fertility and considering pregnancy are a self-selected population; therefore, to reduce potential bias, cases were matched on recurrence status at time of conception. Although the number of cases was limited, subgroup analyzes indicated a small, nonsignificant adverse effect among women who conceived within 12 months of diagnosis. This analysis of carefully matched cases provides reassurance that long-term prognosis was not adversely affected by subsequent pregnancy.
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Neoplasias de la Mama/mortalidad , Complicaciones Neoplásicas del Embarazo/mortalidad , Adulto , Femenino , Estudios de Seguimiento , Humanos , Análisis Multivariante , Recurrencia Local de Neoplasia , Embarazo , Pronóstico , Modelos de Riesgos ProporcionalesRESUMEN
BACKGROUND: XRCC1 is a scaffold protein involved in the early and late stages of Base Excision Repair (BER). Three DNA polymorphisms occur in XRCC1, resulting in non-synonymous amino acid changes, which could alter the binding or regulatory activities of XRCC1. MATERIALS AND METHODS: We used a family-based case-control study design to evaluate the association between XRCC1 polymorphisms and breast cancer risk. Participants were breast cancer cases and their unaffected sisters enrolled in the New York Site of the Breast Cancer Family Registry. Conditional logistic regression was used to assess associations between genotype and breast cancer. XRCC1 mRNA levels and DNA nicking activity were measured in lymphoblastoid cell lines from unaffected sisters to determine whether the XRCC1 R399Q polymorphism has a functional effect on expression or protein activity. RESULTS: XRCC1 194W was associated with a non-significant increase in breast cancer, while XRCC1 280H and XRCC1 399Q were associated with a non-significant decrease in breast cancer. We found a significant increase in XRCC1 expression in 399Q/Q lymphoblastoid cell lines from unaffected sisters (n=28, P=0.03). An increase in median nicking activity was not statistically significant. CONCLUSIONS: Our results suggest that XRCC1 399Q may alter mRNA expression and DNA repair phenotype, although the main effects of the genotype were not significantly associated with familial cancer risk. Additional research on the regulation of XRCC1 expression will contribute to an understanding of how this polymorphism may impact disease risk.
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Background. MicroRNAs are a type of small noncoding RNA molecules that have been shown to control gene expression in eukaryotes. Aberrant expression and alteration of miRNAs may be responsible for human diseases including cancer. An miR16-1 (C > T) + 7 gene mutation has been previously found in familial chronic lymphocytic leukemia patients, one of which reported a family history of breast cancer. miR16-1 regulates the expression of bcl-2, which is important in retinoblastoma, and is located in a genomic region that is frequently lost in nasopharyngeal and hepatocellular carcinomas (HCCs). Therefore, miR16-1 may be potentially important in the etiology of several solid tumors. To understand the power of the miR16-1 (C > T) + 7 mutation as a prognostic and diagnostic risk factor, we investigated the mutation in patients with seven different types of cancer including 188 with breast, 102 with ovarian, and 22 nasopharyngeal carcinomas, 96 HCC, 872 chronic myeloid leukemia (CML), 39 chronic lymphocytic leukemia (CLL), and 46 retinoblastoma cases from three different ethnic groups and of hereditary and sporadic etiology. Methods. 5'Nuclease TaqMan SNP genotyping assay was used to detect the miR16-1 gene C > T substitution. Results. The miR16-1 (C > T) + 7 substitution was not detected in any of the groups studied. Conclusions. Considering the large scale of our study, the representation of different ethnicities and levels of hereditary risk, we conclude that the miR-16-1 (C > T) + 7 mutation is not a good diagnostic or prognostic indicator of risk for the cancers tested.
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In addition to classic genetic mechanisms such as deletions and mutations, growth regulatory genes can be inactivated via methylation of cytosine-residues in their promoter regions. Hypermethylation of promoter CpG islands is now recognized as an important and early event in carcinogenesis. Detection of methylated DNA in serum or plasma has been suggested to be a marker for early cancer development. We examined methylation changes in RASSF1A, a growth regulatory gene in plasma DNA from blood collected before diagnosis from women with breast cancer and from controls. Samples were from two sets of subjects, 28 women with breast cancer and 10 of their unaffected siblings, and 33 women with breast cancer and 29 age- and ethnicity-matched population-based controls. Using methylation specific PCR, we found 11 of 61 (18%) cases were positive for methylation of RASSF1A in their plasma DNA collected before diagnosis. Two of 10 healthy high-risk sibling controls (20%) had plasma DNA positive for RASSF1A methylation in their plasma DNA compared with 0 of 29 (0%) population-based controls. Tumor tissue was available for 12 cases and all were positive for RASSF1A methylation. These results, if replicated, suggest that aberrant promoter hypermethylation in serum/plasma DNA may be common among high-risk women and may be present years before cancer diagnosis.
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Neoplasias de la Mama/genética , Metilación de ADN , ADN de Neoplasias/sangre , Proteínas Supresoras de Tumor/genética , Adulto , Neoplasias de la Mama/sangre , Neoplasias de la Mama/diagnóstico , Estudios de Casos y Controles , ADN de Neoplasias/genética , Femenino , Predisposición Genética a la Enfermedad , Humanos , Persona de Mediana Edad , Regiones Promotoras GenéticasRESUMEN
Reactive oxygen species are important in the pathogenesis of many diseases, including breast cancer. Several population-based case-control studies have shown that various biomarkers of oxidative stress are associated with an increase in breast cancer risk. We selected sisters discordant for breast cancer (n=645) from the New York site of the Breast Cancer Family Registry to explore factors that contribute to variation in plasma protein carbonyls, and to determine whether this biomarker is associated with an increase in breast cancer risk among those with a family history. Late age at menarche, hormone replacement therapy use, and Hispanic race were significantly associated with lower plasma protein carbonyl levels in unaffected sisters. Plasma protein carbonyls were associated with an increase in breast cancer risk [Q2 odds ratio (OR), 1.4; 95% confidence interval (CI), 0.8-2.7; Q3 OR, 2.4; 95% CI, 1.1-4.9; Q4 OR, 1.9; 95% CI, 0.8-4.2], although not in a dose-dependent manner. These data suggest that oxidative damage is a risk factor for breast cancer in high-risk women.
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Proteínas Sanguíneas/metabolismo , Neoplasias de la Mama/sangre , Proteínas de Neoplasias/sangre , Carbonilación Proteica , Adolescente , Adulto , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , Estudios de Casos y Controles , Connecticut/epidemiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Persona de Mediana Edad , New Jersey/epidemiología , New York/epidemiología , Sistema de Registros , Factores de Riesgo , Hermanos , Adulto JovenRESUMEN
PURPOSE: BRCAPRO, a BRCA mutation carrier prediction model, was developed on the basis of studies in individuals of Ashkenazi Jewish and European ancestry. We evaluated the performance of the BRCAPRO model among clinic-based minority families. We also assessed the clinical utility of mutation status of probands (the first individual tested in a family) in the recommendation of BRCA mutation testing for other at-risk family members. PATIENTS AND METHODS: A total of 292 minority families with at least one member who was tested for BRCA mutations were identified through the Breast Cancer Family Registry and the University of Chicago. Using the BRCAPRO model, the predicted likelihood of carrying BRCA mutations was generated. Area under the receiver operating characteristic curves (AUCs) were calculated. RESULTS: There were 104 African American, 130 Hispanic, 37 Asian-American, and 21 other minority families. The AUC was 0.748 (95% CI, 0.672 to 0.823) for all minorities combined. There was a statistically nonsignificant trend for BRCAPRO to perform better in Hispanic families than in other minority families. After taking into account the mutation status of probands, BRCAPRO performance in additional tested family members was improved: the AUC increased from 0.760 to 0.902. CONCLUSION: The findings support the use of BRCAPRO in pretest BRCA mutation prediction among minority families in clinical settings, but there is room for improvement in ethnic groups other than Hispanics. Knowledge of the mutation status of the proband provides additional predictive value, which may guide genetic counselors in recommending BRCA testing of additional relatives when a proband has tested negative.
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Negro o Afroamericano/genética , Neoplasias de la Mama/genética , Genes BRCA1 , Genes BRCA2 , Hispánicos o Latinos/genética , Mutación , Adulto , Anciano , Neoplasias de la Mama/etnología , Femenino , Humanos , Persona de Mediana Edad , Grupos Minoritarios , OvariectomíaRESUMEN
The Breast Cancer Family Registry is a resource for interdisciplinary and translational studies of the genetic epidemiology of breast cancer. This resource is available to researchers worldwide for collaborative studies. Herein, we report the results of testing for germline mutations in BRCA1 and BRCA2. We have tested 4,531 probands for mutations in BRCA1 and 4,084 in BRCA2. Deleterious mutations in BRCA1 and BRCA2 were identified for 9.8% of probands tested [233/4,531 (5.1%) for BRCA1 and 193/4,084 (4.7%) for BRCA2]. Of 1,385 Ashkenazi Jewish women tested for only the three founder mutations, 17.4% carried a deleterious mutation. In total, from the proband and subsequent family testing, 1,360 female mutation carriers (788 in BRCA1, 566 in BRCA2, 6 in both BRCA1 and BRCA2) have been identified. The value of the resource has been greatly enhanced by determining the germline BRCA1 and BRCA2 mutation statuses of nearly 6,000 probands.
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Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , Genes BRCA1 , Genes BRCA2 , Predisposición Genética a la Enfermedad , Sistema de Registros , Análisis Mutacional de ADN , Femenino , Efecto Fundador , Mutación de Línea Germinal , Heterocigoto , Humanos , Judíos/genética , LinajeRESUMEN
The protective effect of full-term pregnancy against breast cancer is thought to be induced by two placental hormones: human chorionic gonadotropin and human chorionic somatotropin hormone (CSH) produced by the placental trophoblastic cells. We hypothesized that variants in placental genes encoding these hormones may alter maternal breast cancer risk subsequent to pregnancy. We conducted a case-control study to examine the association between polymorphisms in a woman's placental (i.e., her offspring's) homologous chorionic gonadotrophin beta5 (CGB5) and CSH1 genes and her post-pregnancy breast cancer risk. A total of 293 breast cancer cases and 240 controls with at least one offspring with available DNA were selected from the New York site of the Breast Cancer Family Registry. Three single nucleotide polymorphisms (SNP) in CGB5 and CSH1 genes were genotyped for 844 offspring of the cases and controls. Overall, maternal breast cancer risk did not significantly differ by the offspring's carrier status of the three SNPs. Among women with an earlier age at childbirth (younger than the median age of 26 years), those with a child carrying the variant C allele of CGB5 rs726002 SNP had an elevated breast cancer risk [odds ratio (OR), 2.09; 95% confidence interval (95% CI), 1.17-3.73]. Among women with a later age at childbirth, breast cancer risk did not differ by offspring's carrier status of CGB5 rs726002 SNP (OR, 0.90; 95% CI, 0.53-1.51; P for interaction=0.04). The findings suggest that placental CGB5 genotype may be predictive of maternal post-pregnancy breast cancer risk among women who give birth early in life.
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Neoplasias de la Mama/genética , Gonadotropina Coriónica/genética , Placenta/fisiología , Lactógeno Placentario/genética , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , EmbarazoRESUMEN
Unrepaired DNA double-strand breaks (DSBs) may have serious consequences for cells by inducing chromosomal aberrations, thereby increasing genetic instability and cancer risk. One's capacity to repair DSB is therefore an important factor to consider when estimating cancer risk. We assessed DNA end-joining (EJ) capacity in cell lines derived from sisters discordant for breast cancer to determine if individual differences in DSB repair are a significant risk factor. We used an in vitro phenotypic assay on nuclear extracts from lymphoblasts of 179 subjects including 86 cases and 93 controls. EJ activity was functionally estimated as the ability of extracts to join together monomers of the plasmid pUC18 linearized either with sticky (EcoRI) or blunt ends (HincII). Mean percentage of EJ capacity was slightly lower in cases than controls, both for EcoRI (cases 27.9 +/- 11.1; controls 29.6 +/- 10.7, P = 0.28) and HincII substrates (cases 28.8 +/- 12.2; controls 30.6 +/- 13.0, P = 0.36); however, no significant differences were observed. Categorizing EJ capacity into tertiles and using the highest activity as the referent, we observed elevated associations for each tertile of decreased repair [Odds ratio (OR) = 2.20, 95% confidence interval (CI) = 0.77-6.22 and OR = 4.22, 95% CI thinsp;= 1.22-14.0, P = 0.02], respectively, for EcoRI. Results were not statistically significant for HincII (OR = 1.37, 95% CI = 0.51-3.70 and OR = 2.32, 95% CI = 0.57-9.38, P = 0.24). These data suggest that individual differences in EJ capacity may represent a risk factor predisposing women to breast cancer.
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Neoplasias de la Mama/genética , Roturas del ADN de Doble Cadena , Reparación del ADN , ADN de Neoplasias/genética , Linfocitos/fisiología , Neoplasias de la Mama/sangre , Neoplasias de la Mama/patología , Línea Celular Tumoral , Transformación Celular Neoplásica/genética , Femenino , Predisposición Genética a la Enfermedad , Humanos , Linfocitos/patología , Persona de Mediana Edad , HermanosRESUMEN
Cancer screening rates are lower among Asian Americans than the general USA population. While prior studies examined characteristics of Asian American patients as predictors of cancer screening, few investigated their health care providers. Asian American primary care physicians practicing in New York City were surveyed by questionnaire regarding their demographics, practice characteristics, and cancer screening of their Asian American patients. Of the 117 eligible respondents, 96% recommended mammograms to their Asian patients 50+ years of age and 70% to patients 40-49-year-old. Only 30% of respondents use both age and onset of sexual activity to determine when to recommend Pap smears. For colorectal cancer screening, the rates of performing fecal occult blood testing or recommending colonoscopy or sigmoidoscopy were 77% and 74%. About 70% recommend screening for hepatitis B. Gender and ethnicity of the physician were found to be significant predictors for cancer screening practice.
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Asiático/estadística & datos numéricos , Tamizaje Masivo/estadística & datos numéricos , Neoplasias/diagnóstico , Médicos de Familia/estadística & datos numéricos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Actitud del Personal de Salud/etnología , Femenino , Hepatitis B/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Ciudad de Nueva York , Factores SexualesRESUMEN
Telomeres consist of a tandem repeats of the sequence TTAGGG at the ends of chromosomes and play a key role in the maintenance of chromosomal stability. Previous studies indicated that short telomeres are associated with increased risk for human bladder, head and neck, lung, and renal cell cancer. We investigated the association between white blood cell telomere length and breast cancer risk among 268 family sets (287 breast cancer cases and 350 sister controls). Telomere length was assessed by quantitative PCR. The mean telomere length was shorter in cases (mean, 0.70; range, 0.03-1.95) than in unaffected control sisters (mean, 0.74; range, 0.03-2.29), but no significant difference was observed (P = 0.11). When subjects were categorized according to the median telomere length in controls (0.70), affected sisters had shorter telomeres compared with unaffected sisters after adjusting for age at blood donation and smoking status [odds ratio (OR), 1.3; 95% confidence interval (95% CI), 0.9-1.8], but the association was not statistically significant. The association by quartile of telomere length (Q4 shortest versus Q1 longest) also supported an increase in risk from shorter telomere length, although the association was not statistically significant (OR, 1.6; 95% CI, 0.9-2.7). This association was more pronounced among premenopausal women (OR, 2.1; 95% CI, 0.8-5.5) than postmenopausal women (OR, 1.3; 95% CI, 0.5-3.6 for Q4 versus Q1). If these associations are replicated in larger studies, they provide modest epidemiologic evidence that shortened telomere length may be associated with breast cancer risk.
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Neoplasias de la Mama/genética , Telómero/genética , Adulto , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Humanos , Persona de Mediana Edad , HermanosRESUMEN
Moderate alcohol intake has been consistently associated with a modest (30-50%) increase in breast cancer risk, but it remains unclear if certain individuals have higher susceptibility to the harmful effects of alcohol intake. Individuals differ in their ability to metabolize alcohol through genetic differences in alcohol dehydrogenase (ADH), the enzyme that catalyzes the oxidation of approximately 80% of ethanol to acetaldehyde, a known carcinogen. Using data from the Breast Cancer Family Registry (n = 811 sister sets), we examined whether sisters with breast cancer differ with respect to alcohol consumption and alcohol metabolism (measured by polymorphisms in ADH1B and ADH1C) compared to their sisters without breast cancer. Neither alcohol drinking nor alcohol metabolizing ADH1B and ADH1C genotypes were associated with breast cancer risk. However, only 19% and 42% of sisters were discordant by ADH1B and ADH1C, respectively, and even fewer were discordant by both genotype and alcohol intake, making it difficult to detect differences if they existed.
Asunto(s)
Alcohol Deshidrogenasa/genética , Consumo de Bebidas Alcohólicas/efectos adversos , Neoplasias de la Mama/genética , Etanol/metabolismo , Neoplasias de la Mama/etiología , Neoplasias de la Mama/metabolismo , Estudios de Casos y Controles , Femenino , Genotipo , Humanos , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Sistema de Registros , Factores de RiesgoRESUMEN
We examined associations between polymorphisms in genes related to estrogen metabolism (CYP1B1 codon 432G --> C rs#1056836, CYP1B1 codon 453A --> G rs#1800440, COMT codon 158G --> A rs#4680) and biosynthesis (CYP17 T --> C promoter rs#743572, CYP19 exon 4 TTTA repeat) and urinary estrogen metabolites (2-hydroxyestrogens (2-OHE), 16alpha-hydroxyestrone (16alpha-OHE1), and their ratio) in a pilot study of 64 pre- and post-menopausal women with a family history of breast cancer. Women were participants in the Metropolitan New York Registry of Breast Cancer Families, one of six international sites of the National Cancer Institute's Breast Cancer Family Registry. We used linear regression to examine the effects of genetic variants on log-transformed urinary estrogen metabolites. After adjusting for menopausal status, BMI, and age, carriers of the CYP1B1 codon 453G variant allele had 31.0% lower levels of 2-OHE (P-value = 0.05) and 40.2% lower levels of 16alpha-OHE1 (P = 0.01). Results were similar after restricting the analyses to pre-menopausal women (n = 41). Consistent with other studies, among pre-menopausal women, carriers of the COMT codon 158A variant allele had increased 2-OHE levels (P = 0.03) and an increased 2-OHE/16alpha-OHE1 ratio (P = 0.04); carriers of the CYP17 C promoter variant allele had increased 2-OHE levels (P = 0.08). To our knowledge this is the first report showing associations between the CYP1B1 codon 453G variant allele and urinary 2-OHE and 16alpha-OHE1 metabolites. Further larger studies should be conducted to confirm these results. Future identification of individuals with genetic polymorphisms that affect estrogen metabolism and biosynthesis may help characterize women at higher breast cancer risk and could guide breast cancer prevention strategies for those individuals.
Asunto(s)
Neoplasias de la Mama/metabolismo , Estrógenos/metabolismo , Polimorfismo Genético , Adulto , Anciano , Hidrocarburo de Aril Hidroxilasas/genética , Catecol O-Metiltransferasa/genética , Codón , Citocromo P-450 CYP1B1 , Estradiol/análogos & derivados , Estradiol/orina , Femenino , Humanos , Hidroxiestronas/orina , Persona de Mediana Edad , Esteroide 17-alfa-Hidroxilasa/genéticaRESUMEN
BACKGROUND: Understanding the effect of oral contraceptives on risk of breast cancer in BRCA1 or BRCA2 mutation carriers is important because oral contraceptive use is a common, modifiable practice. METHODS: We studied 497 BRCA1 and 307 BRCA2 mutation carriers, of whom 195 and 128, respectively, had been diagnosed with breast cancer. Case-control analyses were conducted using unconditional logistic regression with adjustments for family history and familial relationships and were restricted to subjects with a reference age under 50 years. RESULTS: For BRCA1 mutation carriers, there was no significant association between risk of breast cancer and use of oral contraceptives for at least 1 year [odds ratio (OR), 0.77; 95% confidence interval (95% CI), 0.53-1.12] or duration of oral contraceptive use (P(trend) = 0.62). For BRCA2 mutation carriers, there was no association with use of oral contraceptives for at least 1 year (OR, 1.62; 95% CI, 0.90-2.92); however, there was an association of elevated risk with oral contraceptive use for at least 5 years (OR, 2.06; 95% CI, 1.08-3.94) and with duration of use (OR(trend) per year of use, 1.08; P = 0.008). Similar results were obtained when we considered only use of oral contraceptives that first started in 1975 or later. CONCLUSIONS: We found no evidence overall that use of oral contraceptives for at least 1 year is associated with breast cancer risk for BRCA1 and BRCA2 mutation carriers before age 50. For BRCA2 mutation carriers, use of oral contraceptives may be associated with an increased risk of breast cancer among women who use them for at least 5 years. Further studies reporting results separately for BRCA1 and BRCA2 mutation carriers are needed to resolve this important issue.