| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Regular Articles |
1 Human Genetics Section, Laboratory of Genomic Diversity, National Cancer Institute at Frederick, Frederick, Maryland; 2 Celera Diagnostics or Celera, Inc, Rockville, Maryland or Alameda, California; 3 SAIC-Frederick, Inc, Frederick, Maryland; 4 Memorial Sloan-Kettering Cancer Center, New York, New York; 5 Applied Biosystems, Rockville, Maryland; 6 Department of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts; and 7 Department of Pathology, Vanderbilt University School of Medicine, Nashville, Tennessee
| ABSTRACT |
|---|
|
|
|---|
O.4; 95% confidence interval (CI), 0.20.8; P < 0.01]. Another haplotype was associated with an increased risk of breast cancer (OR, 2.1; 95% CI, 1.23.8; P < 0.05). A unique risk haplotype was present in
7% of older Ashkenazi Jewish study subjects (OR, 1.7; 95% CI, 1.22.4; P < 0.003). We narrowed the ESR1 risk haplotypes to the promoter region and first exon. We define several other haplotypes in Ashkenazi Jews in both ESR1 and ESR2 that may elevate susceptibility to breast cancer. In contrast, we found no association between any PGR variant or haplotype and breast cancer. Genetic epidemiology study replication and functional assays of the haplotypes should permit a better understanding of the role of steroid receptor genetic variants and breast cancer risk. | INTRODUCTION |
|---|
|
|
|---|
30% (4)
, suggesting that genes other than the well-mapped regions act as modifiers of breast cancer risk. Although it is likely low penetrance as well as high penetrance genes may be involved in the etiology, it remains unclear which genomic regions and which biochemical functions or signal transduction pathways account for additional, heritable breast cancer incidence or progression. Abundant epidemiologic evidence suggests that estrogen plays a crucial role in most breast cancers. Nulliparous women are at significantly elevated risk, as are women who have children late in their lives, women who have early menarche or women who have late menopause. Obesity is also associated with breast cancer risk; estrogen synthesis in adipose tissue is proposed to account for this increase in risk. Whereas estrogen receptor (ER)-positive and progesterone receptor (PgR)-positive breast cancers have better short-term prognosis than those that have become hormone independent (5) , receptor status varies as a function of age and menopausal status. Younger patients are more likely receptor negative and hormonally unresponsive; older patients are more often receptor positive and hormonally responsive. Recent and complete reviews of the genetics of breast cancer and its relation to the estrogen and progesterone receptor are available (6, 7, 8, 9, 10, 11, 12) .
In this report, we seek to identify candidate steroid hormone receptor gene variants in ESR1, ESR2, and PGR that might be associated with risk of breast cancer, perhaps leading to accelerated or slower rates of neoplastic transformation.8
| MATERIALS AND METHODS |
|---|
|
|
|---|
5'-Nucleotidase Assay Method.
Five nanograms of genomic patient and control DNAs were aliquoted with a Hydra liquid handler (HYDRA Robbins Molecular BioProducts, San Diego, CA) into 384-well bar-coded optical thermocycler plates compatible with the ABI PRISM 7900HT sequence detection system (ABI Prism 7900 HT, Applied Biosystems, Inc., Foster City, CA). Before assay, these were rehydrated with 2.4 µL of deionized water with a Qfill2 automated pipetter (QFILL2 Genetix Ltd., Queensway, New Milton Hampshire, United Kingdom). For Assays-on-Demand products (denoted by a catalog number and paucity of sequence information in Table 1
), 2.5 µL of TaqMan Universal PCR master mix was added with 125 nL of Assay-on-Demand mix per well. For Assays-by-Design products or assays devised in house, 2.5 µL of PCR master mix was combined with 100 µmol of each primer (45 nl each) and 100 µmol of each probe (10 nl each). Plates were sealed and cycled at 95°C for 10 minutes, followed by 50 cycles of 95°C for 15 seconds, 58°C for 1 minute in an ABI GeneAmp PCR System 9700 thermocycler set for 9600 emulation. At the end of cycling, plates were held at 25°C until reading in a 7900 HT sequence detection system. Each plate contained controls of each genotype and no template controls. Data from plates failing any control were discarded. Manual genotype calls were done conservatively, consistent with the standards discussed in Clark et al.(13)
and missing values were excluded from the analysis as detailed in Results. Aggregate indeterminate genotypes averaged 1% of total ESR1 SNPs sampled (range, 0.42%). Genotype tabulations and missing value details are provided as supplementary data.9
|
|
A map with SNP location details is provided as Fig. 1
.
|
50 and age >50). To address the effect of age of menopause, a surrogate marker (age < or >50) was used. Five males with breast cancer and two male controls were included in the study, but excluded for the statistical analysis presented here. No result presented here was significantly impacted when we included or excluded these males. For the purpose of haplotype estimation, the most common alleles in the study as a whole were represented by "1" for ESR1 loci, and "A" for ESR2 loci; in addition, efforts are made to describe each haplotype by the base letter of the variants that compose it. Map coordinates provided are those from NCBI Build 33 (April 2003).17
SNP name designations are consistent with those defined in dbSNP when possible. The strategy used to search for statistically significant haplotypes consisted of, first, using the EM algorithm or a Bayesian model to provide haplotype estimates; second, these estimated haplotypes were used to identify htSNPs (haplotype-tagging SNPs; ref. 20 ) representing a minimal informative subset of SNPs in each gene of interest (21) . Haplotype-tagging SNPs for ESR1 were chosen through use of the software program PHASEpybest.py.18 Rare haplotypes representing less than 1% of the total were deleted for the purpose of determining htSNPs. HT SNP Tester (at the same web site) was used to determine the final set of htSNPs used in the analysis, which included rare haplotypes. We used a permutation program [SNPEM (22) or PHASE 2.02 (14) ] to evaluate the statistical significance of any association observed between haplotype and disease state. Schaids program, haplo.score [Schaid et al. (19) ] which uses an E-M algorithm to estimate haplotypes and then tests disease association through a general linear model, was used to verify significant associations discovered with SNPEM. For sparse data, haplo.score computes simulation P-values for all score tests of association. In addition to our htSNP work, we performed two separate haplotype association analyses on blocks of strong linkage disequilibrium in ESR1.
CaseControl Sample Description.
Breast cancer cases consisted of 1,006 female patients with histologically confirmed breast cancer who presented for treatment or consultation at Memorial Sloan Kettering Cancer Center from January 2000 through December 2001. DNA was obtained from peripheral blood samples. Information was obtained on age at time of diagnosis of breast cancer, age at donation of blood sample, histologic confirmation of breast cancer diagnosis, sex, and ethnicity. All DNA samples were permanently anonymized according to an Institutional Review Board (IRB)-approved protocol. Samples were unselected for family history or any other demographic characteristic. Control subjects were drawn from the New York Cancer Study. The New York Cancer Study is a cohort study, modeled after the Framingham study, in which 18,187 individuals were enrolled from January 2000 through December 2002 (23)
. Individuals were recruited at 14 sites in the New York metropolitan area. Volunteers were recruited by advertisement targeted to an ethnically diverse community. Volunteers were all individually interviewed and filled out a questionnaire that took 1 hour. Individuals were from 30 to 65 years of age. Individuals provided informed consent for use of DNA, which was obtained from 50 cc of whole blood. Information was gathered on age, sex, personal medical history, ethnicity (by 2000 Census nomenclature), family history, substance use, reproductive history and medication use. For the cohort group, a subset of 613 subjects were chosen who were female, free of breast cancer, and with age and ethnicity annotating each sample. Other information, including all personal identifiers were permanently removed, according to instructions of participating IRBs. IRB approval for the study stipulated that no clinical information beyond case or control designation, sex, ethnicity and age could be linked to samples subsequent to anonymization for DNA analysis. Controls were age, sex, and ethnically matched to cases. In both cases and controls, DNA was extracted from peripheral blood lymphocytes with Qiagen QIAamp Blood kits (Qiagen GmbH, Hilden, Germany) and then spectrophotometrically quantitated. Human subjects research approvals were obtained at Memorial Sloan-Kettering Cancer Center, and an exemption was obtained at the National Cancer Institute. Among 1,626 research subjects, 7 males were excluded from the final analysis on account of their sex. The inclusion or exclusion of these males had an insignificant impact on our statistical conclusions. The female case population was composed of 927 European Americans, 388 Ashkenazi Jews, 149 African Americans, 81 research subjects of Hispanic ethnicity, 39 Asians, and 35 subjects for whom no ethnicity or race was provided.
Verification Data Set.
On completion of genotyping and analysis from the New York Academic Medical Development Corporation (NY AMDeC) study, we were provided a set of incomplete genotyping data from 298 breast cancer cases and 94 controls from a study conducted at Vanderbilt University School of Medicine. Investigators there (24)
had typed five SNPs in ESR1 during the early 1990s, but have recently added to their data set. Although these investigators have now typed seven SNPs (rs2077647, rs746432, Intron 1 PvuII (which is rs2234693 or c.454397T>C), intron 1 XbaI (which is rs9340799 or c.454351A>G), Exon 2 codon 160, rs1801132, and rs2228480), only four (rs746432, rs2234693, rs9340799, and rs1801132) provide sufficient information to assemble 564 useful haplotypes from 282 individuals (190 cases and 94 controls).
| RESULTS |
|---|
|
|
|---|
|
50. A comparison of the age match between cases and controls is available as supplementary data at ftp://ftp.ncifcrf.gov/pub/users/goldb/in a folder labeled CANCERRESEARCH.9
Differences in the genotype distributions between cases and controls were tested with the
2 test, Fishers Exact Test, and a Monte Carlo test. Although no SNPs were differentially distributed among aggregate cases and controls in a statistically significant way, when the population was age-stratified into an age 50-and-under and an over-50 age group, three ESR1 SNPs were statistically significantly associated (with P-values
0.01, 0.001, and 0.003 by Fishers Exact Test) with disease in the Jewish population; these are ESR1002, rs2077647, and rs827421 respectively (see Fig. 3
|
|
|
Susceptible Haplotypes of ESR1.
Among all female study participants, H3 and H4 evidenced statistically significant susceptibility to breast cancer. H3 evidenced susceptibility when only older study subjects were considered. This haplotype (H3) was very rare among African Americans, and did not evidence significant susceptibility in study participants ages 50 or under. Haplotype H8: 12111111 (G-G-C-T-G-G-G-T) was not associated with an increased risk of breast cancer when the data set as a whole was considered, but was significant by two measures (P-value from SNPEM = 0.014 and P-value from haplo.score
0.02) when only self-identified Ashkenazi-Jewish research subjects were analyzed, although the 95% CIs encompass unity when males are excluded from the analysis [OR, 3.292; 95% CI, 0.94511.471 (OR, 3.706; 95% CI, 1.07612.757; P < 0.01 with males included in the analysis)]. A separate susceptible haplotype localized to five (of the eight htSNPs) distal to the protective haplotype. In this analysis, rs2077647, hCV1576295, rs1801132, rs6905370, and rs2228480 formed haplotype H2a 11221 (C-T-C-A-G) that accounted for 2.6% of the study subjects with a P < 0.001 for risk, an OR of 1.776 (95% CI, 1.0013.152). This is consistent with a susceptible haplotype mapping to exon 4 and intron 4, which might implicate the ligand-binding domain of ER
.
We reanalyzed the ESR1 data with two blocks of SNPs in clear linkage disequilibrium for association with breast cancer, i.e., SNPs 2, 3, 4, 5, 6, and 7 as one block and SNPs 10, 11, 12, and 13 as another block for association analysis. We found some susceptibility in older European-American study participants (P < 0.05) in a haplotype of 221 or G-A-C for rs1884051-rs6905370-rs926778, but the ORs varied only between 1.4 and 1.8, with each 95% CI overlapping unity, yet with significance with the SNPEM permutation algorithm (22) preserved among older European Americans (P < 0.05). This haplotype was very rare in Jews, observed only twice, both times among cases.
Results from the Vanderbilt Validation Data Set.
One haplotype, consisting of four SNPs, from a genotype complete subset of the Vanderbilt casecontrol study (see Materials and Methods), provided a statistically significant association with breast cancer when analyzed with SNPEM and when ORs were computed with SNPhap and SPSS. This haplotype 1211 (C-C-A-G) provided a P-value <0.05 through comparison with a permuted distribution in SNPEM, and a P < 0.004 with Fishers Exact Test (OR, 4.619, 95% CI, 1.37815.481). The haplotype was present in 29 (
5%) of the estimated 568 haplotypes. Among cases, 26 among 345 weighted haplotypes were 1211 (C-C-A-G); among 173 weighted control haplotypes only 3 were 1211 (C-C-A-G). This data set and haplotype also evidenced a greater risk for breast cancer for bearers over age 50 (P < 0.01 by Fishers Exact Test); limiting the analysis to that group demonstrated an OR of 7.9 (95% CI, 1.02560.868). With weighted probabilities and SNPhap on subjects over age 50 to determine the haplotypes, there were 14 cases and only 1 control with this haplotype. Whether 1211 (C-C-A-G) in the Vanderbilt data set overlaps with, or is identical to, one of the haplotypes in the NY AMDeC data set cannot be determined at this time, because there is only a single SNP typed in common in the two casecontrol data sets (rs2077547, or S10S).
Susceptible Haplotype in ESR2 among Ashkenazi Jews.
The 388 self-identified Ashkenazi Jewish females in the study were typed for the eight markers in ESR2 at 14q23.2 described in Fig. 1
. One haplotype, E2H1, formed from the last seven of these SNPs, AAAAAAA (T-C-G-G-T-A-C), beginning with rs1256030, manifested a statistically significant (P = 0.037) susceptibility for breast cancer (OR, 2.317; 95% CI, 1.0425.155; see Table 3
). This was the third most common ESR2 haplotype among the Ashkenazi Jews tested, making up 11.7% of the predicted haplotypes. The 382 Ashkenazim in the study for whom complete genotypes were provided by TaqMan were further investigated with SNPEM. On reduction of the haplotype under investigation to the final five 3' SNPs in ESR2, a new but related haplotype, E2H5, was statistically significant among the Ashkenazim, AAAAA, (C-G-G-T-A; P = 0.001 OR, 1.82; 95% CI, 1.2132.737). Localization of the SNPs providing the haplotype association has been possible through the use of the SNPEM permutation algorithm (Table 3)
. This implicated the four distal (3') SNPs of ESR2 as giving rise to the significant haplotype because the exon 4 C or T polymorphism identified in this study is invariant among the Ashkenazi Jewish subjects.
|
| DISCUSSION |
|---|
|
|
|---|
Although a linkage between late-onset breast cancer and ESR1 was published in 1991 (25) and several published studies find statistically significant associations between ESR1 polymorphisms and breast cancer (24 , 26, 27, 28, 29, 30) , other studies have not shown linkage or association (31, 32, 33) . Each of these studies either had a relative paucity of samples or chose only a few SNPs, with no efforts to generate haplotypes for haplotype estimation and association analysis. Recently, a breast cancer protective association was reported for a GT dinucleotide repeat polymorphism 6627 bp upstream from the transcription start site of ESR1 exon 1 in a large, ethnically homogeneous Han Chinese cohort (GT18 allele; OR, 0.58; 95% CI, 0.360.94; ref. 29 ). Previously, that same group had reported a PvuII polymorphism in intron 1 that was associated with increased breast cancer risk (genotype pp; OR, 1.4; 95% CI, 1.11.8; ref. 30 ). Data suggest that the most frequent allele of this common PvuII polymorphism eliminates a functional binding site for transcription factor B-myb, which may, therefore, down-regulate ESR1 transcription (34 , 35) . Although we have not typed the variants described by Cai et al. (29 , 30) , the magnitude and direction of the protective effects seen by them are consistent with the haplotype data reported here.
Since the discovery of ESR2 in 1996 (36 , 37) , several groups have characterized its unique expression profile (38, 39, 40, 41, 42, 43, 44) , but few have searched for polymorphisms associated with breast cancer risk (45, 46, 47) . Five ESR2 polymorphisms have been identified in the German population (48) , among which, one, rs1256049, provided evidence for an association with anorexia nervosa. This same ESR2 polymorphism had a highly statistically significant association with ovulatory dysfunction in a Chinese population (49) . In addition, an intragenic CA repeat polymorphism in ESR2 has been associated with bone mineral density in a Japanese research subject population (50) . More recently, the Shanghai breast study group reported an ESR2 exon 7 synonymous SNP (rs1256054, L392L) as conferring increased risk of breast cancer (OR, 2.37; 95% CI, 1.184.77) in a robust study (47) . They hypothesized that this SNP may act as an exonic splicing enhancer. We are currently in the process of typing this SNP; although preliminary results indicate that it is quite rare and will likely be uninformative in our European-American and Ashkenazi-Jewish populations (data not shown).
We typed six intronic and 3' SNPs in addition to six of those characterized by De Vivo et al. (51
: +44 C/T, +331 G/A, S344T, G393G, V660L, and H770H). As can be seen through inspection of Fig. 2C
, we found significant linkage disequilibrium throughout the PGR gene as gauged by either the D' or R2 statistic computed for the 12 SNPs that we typed. However, we found no single SNP, nor any haplotype, that was significantly associated with breast cancer when we stratified by age, ethnicity, or both. We sought to determine why we were not able to replicate the association of the functional +331 G/A polymorphism with breast cancer risk reported by De Vivo et al. (51)
. Whereas they found 87% GG at this site among their cases and 90% GG among their controls, we found 93.4% and 93% among our cases and controls, respectively; and whereas they found 87% of this same genotype among their postmenopausal cases with 90% among their postmenopausal controls, we found 93% GG and 93.2% GG among our older cases and controls, respectively. We sought to determine whether this disparity could be explained by demographic differences between the Nurses Health Study participants, polled by De Vivo, and our research subjects by stratifying our results by both ethnicity and age. This analysis of +331 G/A genotypes in cases and controls also yielded no association.
This study has several limitations inherent in its study design. To gain IRB approval, we permanently anonymized DNA samples after collection of a minimum clinical annotation. Thus, it is not now possible to retrospectively examine clinical or demographic records to examine additional potential confounding variables, such as endogenous or exogenous estrogen exposure and other environmental variables. To address the effect of age of menopause, we used a surrogate marker (age < or >50).
Second, our study, although among the largest to date, still lacks statistical power to come to firm conclusions concerning the relationship of ESR1, ESR2, or PGR SNPs or haplotypes with respect to the specific populations tested. Our genotyping adhered to reproducibility and control standards published elsewhere (13) , and we meet recently published genotyping standards (52) . In addition, we demonstrated haplotype segregation in the CEPH families on the five initial SNPs provided by Celera and tested and obtained HardyWeinberg equilibrium in each of our control populations, even although some were quite small.
Although we made an effort to verify our findings in an independent data set, this additional analysis was also underpowered. Nonetheless, the Vanderbilt verification data set confirmed the existence of an ESR1 risk haplotype, which includes the aforementioned PvuII SNP, although it may not be precisely the same haplotype identified in the NY AMDeC study or the Shanghai breast cancer study.
With regard to the statistical limitations inherent in our study design, we used a variety of methods of imputing haplotypes to provide evidence for statistically significant disease associations. Whereas Nyholt (53) has emphasized a critical need for multiple test corrections in disease association studies to avoid Type I error, Krawczak et al., (54) and others (55 , 56) have questioned the overzealous application of the Bonferroni (57) correction. In an attempt to avoid potential errors in inference about associations stemming from the method of determination of haplotypes, we applied several different haplotype inference procedures. We observed that the methods found the common haplotypes accurately, but there was some disagreement in the rare haplotypes. With a variety of methods, some assuming underlying normal distributions, others being permutation based and still others being Bayesian, we have found similar haplotype frequencies in the genes under investigation. Such methods include those of Fallin et al.(15) and Fallin and Schork (22 , 58) , whose haplotype assignment, affection status permutation algorithm has been adopted by Schaid et al. (19) and modified by Stephens and Donnelly (59) . These methods (22) use EM haplotype estimations, which assume compliance with HardyWeinberg equilibrium, whereas Stephens Gibbs sampling algorithm bases haplotype estimations on existent allele frequencies. In all cases of significant association between haplotypes and breast cancer risk, these methods provided consistent haplotype inferences.
Using a variety of statistical and laboratory methods, we have discovered and validated the presence of common polymorphisms in three sex steroid hormone receptor genes. These candidate genes for disease association analysis have functional significance for the etiology under study and, therefore, cannot be thought of as impartially selected for statistical association testing. With cases and controls from the same geographical area and matched for age, we analyzed patterns of linkage disequilibrium and affection trait association with these genetic variants. We were able to define ESR1 haplotypes that conferred significant association with breast cancer risk in a North American population. Whereas the "protective" alleles that have been identified are quite rare in the populations studied, and their overall contribution to disease may be quite small, this analysis of SNP genotypes provides a means to associate variants in steroid hormone receptor genes and the breast cancer phenotype. Continued study of haplotypes of candidate genes in the steroid hormone receptor signal transduction pathway will provide additional insight into the biology of breast neoplasia.
| ACKNOWLEDGMENTS |
|---|
| FOOTNOTES |
|---|
The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
Requests for reprints: Bert Gold, Human Genetics Section, Laboratory of Genomic Diversity, Center for Cancer Research, National Cancer Institute at Frederick, Building 560, Room 21-21, Frederick, MD 21702. Phone: (301) 846-5098; Fax: (301) 846-1909; E-mail: goldb{at}ncifcrf.gov
8 Genetic loci are identified in this publication as ESR1, ESR2 and PGR consistent with Human Genome Organization (HUGO) guidelines. ER
, ERß and PgR refer to the respective peptide products. ![]()
9 ftp://ftp.ncifcrf.gov/pub/users/goldb/ in a folder labeled CANCERRESEARCH. ![]()
10 Authored by Dr. Mark P. Miller (Mark.Miller{at}cnr.usu.edu; Utah State University, Logan, UT) and available from the web page http://bioweb.usu.edu/mpmbio/ or by writing to the author. ![]()
11 By David Clayton (david.clayton{at}cimr.cam.ac.uk; Cambridge Institute for Medical Research, Cambridge, United Kingdom), downloaded from http://www-gene.cimr.cam.ac.uk/clayton/software/. ![]()
12 Written by Matthew Stevens (stephens{at}stat.washington.edu; University of Washington, Seattle, WA) and available from his web site, http://www.stat.washington.edu/stephens/software.html. ![]()
13 Written by Dr. Nicholas Schork and M. Daniele Fallin, and obtained from dfallin{at}jhsph.edu ![]()
14 Obtained from Dr. Jeffrey C. Long (longjc{at}umich.edu; University of Michigan Medical School, Ann Arbor, MI). ![]()
15 The R-version of haplo.score was authored by Dr. Daniel J. Schaid (schaid{at}mayo.edu; Mayo Clinic, Rochester, MN). ![]()
16 Authored by Dr. Jonathan Pritchard (pritch{at}uchicago.edu; The University of Chicago, Chicago, IL) and available at his web site, http://pritch.bsd.uchicago.edu/software.html. ![]()
18 Written by Ross Lazarus at http://www.innateimmunity.net. ![]()
Received 4/ 9/04. Revised 10/ 1/04. Accepted 10/ 6/04.
| REFERENCES |
|---|
|
|
|---|
This article has been cited by other articles:
![]() |
E. Sonestedt, M. I. L. Ivarsson, S. Harlid, U. Ericson, B. Gullberg, J. Carlson, H. Olsson, H. Adlercreutz, and E. Wirfalt The Protective Association of High Plasma Enterolactone with Breast Cancer Is Reasonably Robust in Women with Polymorphisms in the Estrogen Receptor {alpha} and {beta} Genes J. Nutr., May 1, 2009; 139(5): 993 - 1001. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. M. Dunning, C. S. Healey, C. Baynes, A.-T. Maia, S. Scollen, A. Vega, R. Rodriguez, N. L. Barbosa-Morais, B. A.J. Ponder, for SEARCH, et al. Association of ESR1 gene tagging SNPs with breast cancer risk Hum. Mol. Genet., March 15, 2009; 18(6): 1131 - 1139. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Tchatchou, A. Jung, K. Hemminki, C. Sutter, B. Wappenschmidt, P. Bugert, B. H.F. Weber, D. Niederacher, N. Arnold, R. Varon-Mateeva, et al. A variant affecting a putative miRNA target site in estrogen receptor (ESR) 1 is associated with breast cancer risk in premenopausal women Carcinogenesis, January 1, 2009; 30(1): 59 - 64. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Hamaguchi, M. Nishio, T. Toyama, H. Sugiura, N. Kondo, Y. Fujii, and H. Yamashita Possible Difference in Frequencies of Genetic Polymorphisms of Estrogen Receptor {alpha}, Estrogen Metabolism and P53 Genes Between Estrogen Receptor-positive and -negative Breast Cancers Jpn. J. Clin. Oncol., November 1, 2008; 38(11): 734 - 742. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Grans, M. Nilsson, K. Dahlman-Wright, and B. Evengard Reduced levels of oestrogen receptor {beta} mRNA in Swedish patients with chronic fatigue syndrome J. Clin. Pathol., February 1, 2007; 60(2): 195 - 198. [Abstract] [Full Text] [PDF] |
||||
![]() |
The Breast Cancer Association Consortium Commonly studied single-nucleotide polymorphisms and breast cancer: results from the Breast Cancer Association Consortium. J Natl Cancer Inst, October 4, 2006; 98(19): 1382 - 1396. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Dossus, F. Canzian, R. Kaaks, A. Boumertit, and E. Weiderpass No Association between Progesterone Receptor Gene +331G/A Polymorphism and Endometrial Cancer. Cancer Epidemiol. Biomarkers Prev., July 1, 2006; 15(7): 1415 - 1416. [Full Text] [PDF] |
||||
![]() |
K. A. Pooley, C. S. Healey, P. L. Smith, P. D.P. Pharoah, D. Thompson, L. Tee, J. West, C. Jordan, D. F. Easton, B. A.J. Ponder, et al. Association of the progesterone receptor gene with breast cancer risk: a single-nucleotide polymorphism tagging approach. Cancer Epidemiol. Biomarkers Prev., April 1, 2006; 15(4): 675 - 682. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. S. Huggins, J. Y.Y. Wong, S. E. Hankinson, and I. De Vivo GATA5 Activation of the Progesterone Receptor Gene Promoter in Breast Cancer Cells Is Influenced by the +331G/A Polymorphism Cancer Res., February 1, 2006; 66(3): 1384 - 1390. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. T. Landi, P. A. Kanetsky, S. Tsang, B. Gold, D. Munroe, T. Rebbeck, J. Swoyer, M. Ter-Minassian, M. Hedayati, L. Grossman, et al. MC1R, ASIP, and DNA Repair in Sporadic and Familial Melanoma in a Mediterranean Population J Natl Cancer Inst, July 6, 2005; 97(13): 998 - 1007. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. S. Hageman, D. H. Anderson, L. V. Johnson, L. S. Hancox, A. J. Taiber, L. I. Hardisty, J. L. Hageman, H. A. Stockman, J. D. Borchardt, K. M. Gehrs, et al. From The Cover: A common haplotype in the complement regulatory gene factor H (HF1/CFH) predisposes individuals to age-related macular degeneration PNAS, May 17, 2005; 102(20): 7227 - 7232. [Abstract] [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Cancer Research | Clinical Cancer Research |
| Cancer Epidemiology Biomarkers & Prevention | Molecular Cancer Therapeutics |
| Molecular Cancer Research | Cancer Prevention Research |
| Cancer Prevention Journals Portal | Cancer Reviews Online |
| Annual Meeting Education Book | Meeting Abstracts Online |