Diverse Associations between ESR1 Polymorphism and Breast Cancer Development and Progression

Unveiling the ESR1 Conformational Stability and Screening Potent Inhibitors for Breast Cancer Treatment

BACKGROUND

The current study recognizes the significance of estrogen receptor alpha (ERα) as a member of the nuclear receptor protein family, which holds a central role in the pathophysiology of breast cancer. ERα serves as a valuable prognostic marker, with its established relevance in predicting disease outcomes and treatment responses.

METHODS

In this study, computational methods are utilized to search for suitable drug-like compounds that demonstrate analogous ligand binding kinetics to ERα.

RESULTS

Docking-based simulation screened out the top 5 compounds - ZINC13377936, NCI35753, ZINC35465238, ZINC14726791, and NCI663569 against the targeted protein. Further, their dynamics studies reveal that the compounds ZINC13377936 and NCI35753 exhibit the highest binding stability and affinity.

CONCLUSION

Anticipating the competitive inhibition of ERα protein expression in breast cancer, we envision that both ZINC13377936 and NCI35753 compounds hold substantial promise as potential therapeutic agents. These candidates warrant thorough consideration for rigorous In vitro and In vivo evaluations within the context of clinical trials. The findings from this current investigation carry significant implications for the advancement of future diagnostic and therapeutic approaches for breast cancer.

Reducing variability of breast cancer subtype predictors by grounding deep learning models in prior knowledge

Deep learning neural networks have improved performance in many cancer informatics problems, including breast cancer subtype classification. However, many networks experience underspecificationwheremultiplecombinationsofparametersachievesimilarperformance, bothin training and validation. Additionally, certain parameter combinations may perform poorly when the test distribution differs from the training distribution. Embedding prior knowledge from the literature may address this issue by boosting predictive models that provide crucial, in-depth information about a given disease. Breast cancer research provides a wealth of such knowledge, particularly in the form of subtype biomarkers and genetic signatures. In this study, we draw on past research on breast cancer subtype biomarkers, label propagation, and neural graph machines to present a novel methodology for embedding knowledge into machine learning systems. We embed prior knowledge into the loss function in the form of inter-subject distances derived from a well-known published breast cancer signature. Our results show that this methodology reduces predictor variability on state-of-the-art deep learning architectures and increases predictor consistency leading to improved interpretation. We find that pathway enrichment analysis is more consistent after embedding knowledge. This novel method applies to a broad range of existing studies and predictive models. Our method moves the traditional synthesis of predictive models from an arbitrary assignment of weights to genes toward a more biologically meaningful approach of incorporating knowledge.

A Possible Link of Genetic Variations in ER/IGF1R Pathway and Risk of Melanoma

The mechanism of gender disparity in cutaneous melanoma incidence remains unclear. Steroid hormones including estrogens have long been implicated in the course of melanoma, but the conclusion is controversial. Estrogen receptors (ERs) and insulin-like growth factor 1 receptor (IGF1R) show extensive crosstalk in cancer development, but how the ER/IGF1R network impacts melanoma is currently unclear. Here we studied the melanoma associations of selected SNPs from the ER/IGF1R network. Part of the International Genes, Environment, and Melanoma (GEM) cohort was used as a discovery set, and the Gene Environment Association Studies Initiative (GENEVA) dataset served as a validation set. Based on the associations with other malignant disease conditions, thirteen single nucleotide polymorphism (SNP) variants in ESR1, ESR2, IGF1, and IGF1R were selected for candidate gene association analyses. The rs1520220 in IGF1 and rs2229765 in IGF1R variants were significantly associated with melanoma risk in the GEM dataset after Benjamini-Hochberg multiple comparison correction, although they were not validated in the GENEVA set. The discrepancy may be caused by the multiple melanoma characteristics in the GEM patients. Further analysis of gender disparity was carried out for IGF1 and IGF1R SNPs in the GEM dataset. The GG phenotype in IGF1 rs1520220 (recessive model) presented an increased risk of melanoma (OR = 8.11, 95% CI: 2.20, 52.5, p = 0.006) in men but a significant opposite effect in women (OR = 0.15, 95% CI: 0.018, 0.86, p = 0.045). The AA genotype in IGF1R rs2229765 (recessive model) showed a significant protective effect in men (OR = 0.24, 95% CI: 0.07, 0.64, p = 0.008) and no effect in women. Results from the current study are warranted for further validation.

Prognostic impact of genetic variants of CYP19A1 and UGT2B17 in a randomized trial for endocrine-responsive postmenopausal breast cancer

Polymorphisms of genes involved in estrogen synthesis have been linked to breast cancer risk, prognosis, and treatment response. We investigated the prognostic impact of a deletion spanning the entire UGT2B17 gene (UGT2B17*2) and genetic variants of the aromatase CYP19A1 and estrogen receptor α (ESR1) in 125 postmenopausal women with ER-positive breast cancer enrolled in a randomized pre-surgical trial. The UGT2B17*2 was estimated by copy number variation assays and the CYP19A1 rs10046/rs4646 and ESR1 rs2077647/rs2234693/rs9340799 by TaqMan allelic discrimination assays. Serum exemestane/17-hydroxy exemestane were determined by MS and estrone (E1)/estradiol (E2)/ by GC-MS/MS. The association of genetic polymorphisms with "any event" was assessed by the Cox proportional hazards models adjusted for confounders. The UGT2B17*2 was associated with higher levels of 17-hydroxy exemestane (P = 0.04) and better prognosis (HR = 0.45; 95% CI: 0.20-1.01; P = 0.05) compared with homozygote UGT2B17 wt. The CYP19A1 rs10046 A and rs4646 C alleles were associated with higher estrogen levels: rs10046 AA vs. AG/GG genotypes had median E1 of 35.9 vs. 27.4 pg/mL (P = 0.05) and E2 of 7.57 vs. 3.9 pg/mL (P < 0.004). After a median follow-up of 7 years, women carrying the "low estrogen" alleles rs10046 G and rs4646 A had a better prognosis compared with homozygote wt for both polymorphisms (HR = 0.40; 95% CI: 0.17-0.93; P = 0.03). Our analysis points to an impact of UGT2B17 and CYP19A1 in postmenopausal endocrine responsive breast cancer. Carriers of UGT2B17*2 and CYP19A1 low estrogen variants may have better prognosis, supporting studies addressing the role of these polymorphisms in optimizing endocrine therapy. Trial registration: http://www.isrctn.com/ISRCTN86894592.

Association of three single nucleotide polymorphisms of ESR1with breast cancer susceptibility: a meta-analysis

Expression of estrogen receptors is correlated with breast cancer risk, but inconsistent results have been reported. To clarify potential estrogen receptor (ESR)-related breast cancer risk, we analyzed genetic variants of ESR1 in association with breast cancer susceptibility. We performed a meta-analysis to investigate the association between rs2234693, rs1801132, and rs2046210 (single nucleotide polymorphisms of ESR1 ), and breast cancer risk. Our analysis included 44 case-control studies. For rs2234693, the CC genotype had a higher risk of breast cancer compared to the TT or CT genotype. For rs2046210, the AA, GA, or GA+ GG genotype had a much higher risk compared to the GG genotype. No significant association was found for the rs1801132 polymorphism with breast cancer risk. This meta-analysis demonstrates association between the rs2234693 and rs2046210 polymorphisms of ESR1 and breast cancer risk. The correlation strength between rs2234693 and breast cancer susceptibility differs in subgroup assessment by ethnicity.

Impact of CYP19A1 and ESR1 variants on early-onset side effects during combined endocrine therapy in the TEXT trial

Background

Single nucleotide polymorphisms (SNPs) in the estrogen receptor 1 (ESR1) and cytochrome P450 19A1 (CYP19A1) genes have been associated with breast cancer risk, endocrine therapy response and side effects, mainly in postmenopausal women with early breast cancer. This analysis aimed to assess the association of selected germline CYP19A1 and ESR1 SNPs with early-onset hot flashes, sweating and musculoskeletal symptoms in premenopausal patients enrolled in the Tamoxifen and Exemestane Trial (TEXT).

Methods

Blood was collected from consenting premenopausal women with hormone-responsive early breast cancer, randomly assigned to 5-years of tamoxifen plus ovarian suppression (OFS) or exemestane plus OFS. DNA was extracted with QIAamp kits and genotyped for two CYP19A1 (rs4646 and rs10046) and three ESR1 (rs2077647, rs2234693 and rs9340799) SNPs by a real-time pyrosequencing technique. Adverse events (AEs) were recorded at baseline and 3-monthly during the first year. Associations of the genotype variants with grade ≥2 early-onset targeted AEs of hot flashes/sweating or musculoskeletal events were assessed using logistic regression models.

Results

There were 2660 premenopausal patients with breast cancer in the intention-to-treat population of TEXT, and 1967 (74 %) are included in this translational study. The CYP19A1 rs10046 variant T/T, represented in 23 % of women, was associated with a reduced incidence of grade ≥2 hot flashes/sweating (univariate odds ratio (OR) = 0.78; 95 % CI 0.63–0.97; P = 0.03), more strongly in patients assigned exemestane + OFS (TT vs CT/CC: OR = 0.65, 95 % CI = 0.48–0.89) than assigned tamoxifen + OFS (OR = 0.94, 95 % CI = 0.69–1.27, interaction P = 0.03). No association with any of the CYP19A1/ESR1 genotypes and musculoskeletal AEs was found.

Conclusion

The CYP19A1 rs10046 variant T/T favors lower incidence of hot flashes/sweating under exemestane + OFS treatment, suggesting endocrine-mediated effects. Based on findings from others, this SNP may potentially enhance treatment adherence and treatment efficacy. We plan to evaluate the clinical impact of this polymorphism during time, pending sufficient median follow up.

Trial registration

ClinicalTrials.gov NCT00066703, registered August 6, 2003.

Association Between ESR1 PvuII, XbaI, and P325P Polymorphisms and Breast Cancer Susceptibility: A Meta-Analysis

Background

Breast cancer is one of the leading causes of cancer-related deaths for women. Numerous studies have shown that single-nucleotide polymorphisms (SNPs) on the ESR1 gene are associated to this disease. However, data and conclusions are inconsistent and controversial.

Material/Methods

To investigate the association between PvuII (rs2234693), XbaI (rs9340799) and P325P (rs1801132) polymorphisms of ESR1 gene with the risk of breast cancer under different population categorizations, we searched multiple databases for data collection, and performed the meta-analysis on a total of 25 case-control studies. Three different comparison models – dominant model, recessive model, and homozygote comparison model – were applied to evaluate the association.

Results

Our results indicated that people with TT+TC or TT genotype were at a greater risk of developing breast cancer than those with CC genotype in the PvuII polymorphism. While for XbaI and P325P polymorphisms, no significance was found using any of the 3 models. Furthermore, the data were also stratified into different subgroups according to the ethnicity (white or Asian) and source of controls (hospital-based or population-based), and separate analyses were conducted to assess the association. The ethnicity subgroup assessment showed that the higher risk of breast cancer for TT genotype of PvuII polymorphism than CC genotype only occurred in Asian people, but not in white populations. For the source-stratified subgroup analysis, significant association suggested that people with TT + TC genotype were at a greater risk of developing breast cancer than those with CC genotype in the hospital-based subgroup.

Conclusions

Thus, this meta-analysis clarified the inconsistent conclusions from previous studies, conducted analyses for the entire population as well as for different subgroups using diverse population categorization strategies, and has the potential to help provide a personalized risk estimate for breast cancer susceptibility.

Estrogen receptor 1 (ESR1) genetic variations in cancer risk: a systematic review and meta-analysis

BACKGROUND

Emerging published data on the association between single nucleotide polymorphisms (SNPs) in the estrogen receptor 1 (ESR1) gene and cancer susceptibility are inconsistent. This review and meta-analysis is performed to derive a more precise evaluation of this relationship.

METHODS

The literature search of PubMed, Embase, Web of Science and CNKI databases was conducted from their inception through June 2014. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the association.

RESULTS

Twenty-two literatures were enrolled in this meta-analysis. The results indicated that ESR1 rs1801132 (C>G) was associated with cancer risk in Caucasian populations. However, the results of stratified analysis by cancer type and source of controls indicated that no significant association was found. Furthermore, rs2077647 (A>G) was only associated with an increased risk of hepatocellular carcinoma, but was an adverse effect on cancer risk in Caucasian populations.

CONCLUSIONS

This present meta-analysis indicated that rs1801132 (C>G) and rs2077647 (A>G) may be protective factors in Caucasian populations. Meanwhile, rs2077647 (A>G) may be closely related with hepatocellular carcinoma.

Functional variants at the 21q22.3 locus involved in breast cancer progression identified by screening of genome-wide estrogen response elements

Introduction

Estrogen forms a complex with the estrogen receptor (ER) that binds to estrogen response elements (EREs) in the regulatory region of estrogen-responsive genes and regulates their transcription. Sequence variants in the regulatory regions have the potential to affect the transcription factor–regulatory sequence interaction, resulting in altered expression of target genes. This study explored the association between single-nucleotide polymorphisms (SNPs) within the ERE-associated sequences and breast cancer progression.

Methods

The ERE-associated sequences throughout the whole genome that have been demonstrated to bind ERα in vivo were blasted against online information from SNP data sets and 54 SNPs located adjacent to estrogen-responsive genes were selected for genotyping in two independent cohorts of breast cancer patients: 779 patients in the initial screening stage and another 888 in the validation stage. Deaths due to breast cancer or recurrence of breast cancer were defined as the respective events of interest, and the hazard ratios of individual SNPs were estimated based on the Cox proportional hazards model. Furthermore, functional assays were performed, and information from publicly available genomic data and bioinformatics platforms were used to provide additional evidence for the associations identified in the association analyses.

Results

The SNPs at 21q22.3 ERE were significantly associated with overall survival and disease-free survival of patients. Furthermore, these 21q22.3 SNPs (rs2839494 and rs1078272) could affect the binding of this ERE-associated sequence to ERα or Rad21 (an ERα coactivator), respectively, which resulted in a difference in ERα-activated expression of the reporter gene.

Conclusion

These findings support the idea that functional variants in the ERα-regulating sequence at 21q22.3 are important in determining breast cancer progression.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-014-0455-1) contains supplementary material, which is available to authorized users.

The prognostic significance of RUNX2 and miR-10a/10b and their inter-relationship in breast cancer

Background

The major cancer related mortality is caused by metastasis and invasion. It is important to identify genes regulating metastasis and invasion in order to curtail metastatic spread of cancer cells.

Methods

This study investigated the association between RUNX2 and miR-10a/miR-10b and the risk of breast cancer relapse. Expression levels of RUNX2 and miR-10a/b in108 pairs of tumor and non-tumor tissue of breast cancer were assayed by quantitative PCR analysis and evaluated for their prognostic implications.

Results

The median expression levels of RUNX2 and miR-10b in tumor tissue normalized using adjacent non-tumor tissue were significantly higher in relapsed patients than in relapse-free patients. Higher expression of these three genes were significantly correlated with the hazard ratio for breast cancer recurrence (RUNX2: 3.02, 95% CI = 1.50 ~ 6.07; miR-10a: 2.31, 95% CI = 1.00 ~ 5.32; miR-10b: 3.96, 95% CI = 1.21 ~ 12.98). The joint effect of higher expression of all three genes was associated with a hazard ratio of 12.37 (95% CI = 1.62 ~ 94.55) for relapse. In a breast cancer cell line, RUNX2 silencing reduced the expression of miR-10a/b and also impaired cell motility, while RUNX2 overexpression elicited opposite effects.

Conclusions

These findings indicate that higher expression of RUNX2 and miR-10a/b was associated with adverse outcome of breast cancer. Expression levels of RUNX2 and miR-10a/b individually or jointly are potential prognostic factors for predicting breast cancer recurrence. Data from in vitro studies support the notion that RUNX2 promoted cell motility by upregulating miR-10a/b.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-014-0257-3) contains supplementary material, which is available to authorized users.

Menopausal status modifies breast cancer risk associated with ESR1 PvuII and XbaI polymorphisms in Asian women: a HuGE review and meta-analysis

BACKGROUND

Published data on the association between single nucleotide polymorphisms (SNPs) in the ESR1 gene and breast cancer susceptibility are inconclusive or controversial. The aim of this Human Genome Epidemiology (HuGE) review and meta-analysis was to derive a more precise estimation of this relationship.

METHODS

A literature search of Pubmed, Embase, Web of science and CBM databases was conducted from inception through September 1 th, 2012. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association.

RESULTS

A total of five studies including 1,678 breast cancer cases and 1,678 general population controls in Asian populations were involved in this meta-analysis. When all the eligible studies were pooled into the meta-analysis, the higher transcriptional activity variant allele T of ESR1 PvuII (C>T) (rs2234693) in pre-menopausal breast cancer women showed a significant relation to increased risk (OR = 1.13, 95%CI: 1.01-1.28, P = 0.040) in contrast to their post-menopausal counterparts which showed non-significant increased risk (OR = 1.01, 95%CI: 0.87-1.18, P = 0.858). Nevertheless, no significant association between ESR1 XbaI (A>G) (rs9340799) polymorphism and the risk of breast cancer was observed in pre-menopausal and post-menopausal individuals.

CONCLUSION

Based on a homogeneous Asian population, results from the current meta-analysis indicates that the ESR1 PvuII (C>T) polymorphism places pre-menopausal breast cancer women at risk for breast cancer, while ESR1 XbaI (A>G) polymorphism is not likely to predict the risk of breast cancer.

Estrogen receptor α polymorphism in boys with constitutional delay of growth and puberty

PURPOSE

There were a lot of reports regarding associations of polymorphisms in the estrogen receptor α (ESR1). with many disorders. But, those with constitutional delay of growth and puberty (CDGP) are not known. Our aim is to find out any association between CDGP and ESR1.

METHODS

In a total of 27 subjects, we compared 7 CDGP patients with 20 healthy controls with their heights and sexual maturity rates were within normal range. We selected three single nucleotide polymorphisms from intron 1 of ESR1 (rs3778609, rs12665044, and rs827421) as candidates, respectively.

RESULTS

In genotype analyses, the frequency of G/G genotype at rs827421 in intron 1 of ESR1 was increased in CDGP boys (P=0.03).

CONCLUSION

The genetic variation of ESR1 can be a contributing factor of tempo of growth and puberty.

The relationship between eight GWAS-identified single-nucleotide polymorphisms and primary breast cancer outcomes

BACKGROUND

Several single-nucleotide polymorphisms (SNPs) associated with breast cancer risk have been identified through genome-wide association studies (GWAS). We investigated whether eight risk SNPs identified in GWAS were associated with breast cancer disease-free survival (DFS) and overall survival (OS) rates.

PATIENTS AND METHODS

A cohort of 739 white women with early-stage breast cancer was genotyped for eight GWAS-identified SNPs (rs2981582, rs1219648 [FGFR2], rs3803662, rs12443621, rs8051542 [TOX3], rs999737 [RAD51L1], rs6504950 [17q23], and rs4973768 [3p24]). Relationships between SNPs and breast cancer outcomes were evaluated using Cox proportional hazard regression models. The cumulative effects of SNPs on breast cancer outcomes were assessed by computing the number of at-risk genotypes.

RESULTS

At a median follow-up of 121 months (range: 188-231 months) for survivors, 237 deaths (32%) and 186 breast cancer events (25%) were identified among the 739 patients. After adjusting for age, clinical stage, and treatment, rs12443621 (16q12; p = .03) and rs6504950 (17q23; p = .008) were prognostic for OS but not DFS. A higher risk for death was also found in the multivariable analysis of patients harboring three or four at-risk genotypes of the GWAS SNPs compared to patients carrying two or less at-risk genotypes (hazard ratio: 1.60, 95% confidence interval: 1.23-2.24; p = .0008).

CONCLUSION

The study results suggest that previously identified breast cancer risk susceptibility loci, rs12443621 (16q12) and rs6504950 (17q23), may influence breast cancer prognosis or comorbid conditions associated with overall survival. The precise molecular mechanisms through which these risk SNPs, as well as others that were not included in the analysis, influence clinical outcomes remain to be determined.

Characteristics of mammary Paget's disease in China: a national-wide multicenter retrospective study during 1999-2008

The aim of this study was to detail characteristics of mammary Paget's disease (PD) representing the whole population in China. A total of 4211 female breast cancer inpatients at seven tertiary hospitals from seven representative geographical regions of China were collected randomly during 1999 to 2008. Data for demography, risk factors, diagnostic imaging test, physical examination and pathologic characters were surveyed and biomarker status was tested by immunohistochemistry. The differences of demography and risk factors between PD with breast cancer and other lesions were compared using Chi-square test or t-test, with attention to physical examination and pathological characters. The percentage of PD was 1.6% (68/4211) in all breast cancers. The mean age at diagnosis was 48.1, and 63.2% (43/68) patients were premenopausal. There is no difference in demography and risk factors between PD with breast cancer and other breast cancer (P>0.05). The main pattern of PD in physical exam and pathologic pattern were patients presenting with a palpable mass in breast (65/68, 95.6%) and PD with underlying invasive cancer (82.4%, 56/68) respectively. The rate of multifocal disease was 7.4% (5/68). PD with invasive breast cancer showed larger tumor size, more multifocal disease, lower ER and PR expression and higher HER2 overexpression than those in other invasive breast cancer (P<0.05). These results suggested that PD in China is a concomitant disease of breast cancer, and that PD with underlying invasive cancer has more multiple foci and more aggressive behavior compared with other breast invasive cancer. We address the urgent needs for establishing diagnostic and therapeutic guidelines for mammary PD in China.

Prognostic significance of cyclin D1, β-catenin, and MTA1 in patients with invasive ductal carcinoma of the breast

BACKGROUND

To investigate markers for predicting breast cancer progression, we performed a candidate gene-based study that assessed expression change of three genes, cyclin D1, β-catenin, and metastasis-associated protein-1 (MTA1), involving in aggressive phenotypes of cancerous cells, namely hyperproliferation, epithelial-mesenchymal transition, and global transcriptional regulation.

METHODS

Specimens were from 150 enrolled female patients, with invasive ductal carcinoma, followed up for more than 10 years. mRNA expression of cyclin D1, β-catenin, and MTA1 in cancerous and noncancerous cells microdissected from the primary tumor site was determined by quantitative real-time PCR. The relationship between mRNA expression levels of the genes and clinicopathologic features was assessed by statistical analysis. Disease-free and overall survival (DFS and OS) were analyzed by Kaplan-Meier analysis with log-rank test and a multivariate Cox regression model.

RESULTS

Cyclin D1 was shown to be overexpressed in late-stage breast cancer (stage III/IV). Breast cancer with lymph node metastasis (LNM) showed significantly higher frequency of overexpressed cyclin D1, β-catenin, and MTA1 (P < 0.05). Patients carrying greater numbers of overexpressed genes had joint effects on increased risk in tumors of advanced stages (P ( trend ) = 0.03) and LNM (P ( trend ) < 0.01). In the LNM-negative group, patients whose tumors with greater number of cyclin D1, β-catenin, and MTA1 overexpressions were associated with poorer clinical outcomes, with hazard ratio of 14.79 for OS (P = 0.015) and 7.54 for DFS (P = 0.015) using multivariate Cox regression analysis during the 10-year follow-up.

CONCLUSIONS

Higher expression of cyclin D1, β-catenin, and MTA1 mRNAs in breast cancers may prove effective in predicting unfavorable outcomes of breast cancer.

The association between single-nucleotide polymorphisms of ORAI1 gene and breast cancer in a Taiwanese population

Background. Breast cancer is the most common malignancy in women. There is increasing evidence suggesting that ORAI1, components of store-operated calcium channel, play a pivotal role in breast cancer progression and metastasis. Methods. A total of 384 female patients with breast cancer were included in this study. We selected five representative tagging ORAI1 SNPs from HapMap database with minimum allele frequency (MAF) >10%. Genotyping was performed using TaqMan allelic discrimination assay. Chi-square (χ²) test was used to analyze statistical differences among control and patient groups in genotype and allelic frequencies. Results. Two of the ORAI1 SNPs (rs12320939 and rs12313273) were associated with estrogen receptors positive in breast cancer patients under the recessive model. When the Bonferroni correction was performed, the significance still existed. In addition, rs12320939 also associated with the lymph nodal involvement. Conclusion. We showed that genetic polymorphisms of ORAI1 associated strongly with lymph nodal involvement and estrogen receptors (ERs) positive breast cancer patients in a Taiwanese population.

The pathologic characteristics of breast cancer in China and its shift during 1999-2008: a national-wide multicenter cross-sectional image over 10 years

In China, breast cancer is currently the most common malignancy and the sixth leading cause of cancer death in women. But, the characteristics of breast cancer in the whole population are not determined. The aim of this study was to perform a detailed study on pathologic characteristics of breast cancer representing the whole population in China during 1999-2008 and to compare the difference in invasive breast cancer between the Western and Chinese. We randomly collected 4,211 inpatient at seven hospitals in representative geographical regions of China during 1999-2008. All the hospitals had the ability of comprehensive cancer treatment. The pathologic characters including estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status were surveyed. The shift of pathologic characters was evaluated and the data from China were also compared with those of the Western, both using Chi-square test. We found as follow. (i) The median age of the patients was 48 years and showed the similar characters of Asia. (ii) Breast cancer in China showed more invasive ductal carcinoma with larger tumor size, later stage, lower ER and PR expression and higher HER2 overexpression than those in the Western (p < 0.001). (iii) Both tumor size and stage at diagnosis decreased year by year (p < 0.001). Breast cancer in China showed more aggressive behavior than those in western countries, although tumor size and stage at diagnosis decreased by year during 1999-2008. We addressed the urgent needs for employ race-specific breast cancer screen, diagnosis methods, and therapeutic models in China.

Functional variable number of tandem repeats variation in the promoter of proto-oncogene PTTG1IP is associated with risk of estrogen receptor-positive breast cancer

Genetic polymorphisms in the signalling pathway of estrogen receptor (ER) could modify the risk of breast cancer. A variable number of tandem repeats (VNTR) polymorphism in the promoter of PTTG1IP, pituitary tumor transforming gene binding factor targeted by estrogen receptor α (ERα) in endocrine neoplasia, has been shown to be functional, but its relevance to cancer etiology was unknown. We investigated its association with breast cancer risk by genotyping in 658 patients and 866 controls and further analysed its differential interaction with ERα. We found nine types of alleles ranging from 2 to 9 and 11 repeats that form 29 distinct genotypes and 11 different biallelic repeat numbers. Subjects who carry the six-repeats allele (odds ratio [OR], 1.45; 95% confidence interval [CI], 1.17-1.79), long alleles (≥6 repeats) (OR, 1.55; 95% CI, 1.17-2.05) or a high dose of biallelic repeats (OR, 1.38; 95% CI, 1.07-1.77) were at significantly increased risk of cancer. In stratification analysis, these associations consistently manifested in ER-positive breast cancer: in ER positive, PR-positive subtype, genotypes with the six-repeats allele (OR, 1.42; 95% CI, 1.06-1.90), long alleles (OR, 1.77; 95% CI, 1.17-2.67) or a high dose of biallelic repeats (OR, 1.67; 95% CI, 1.19-2.33) were associated with cancer risk; in ER positive, HER2-negative subtype, they were susceptible factors with the ORs being 1.46 (95% CI, 1.06-2.02), 2.06 (95% CI, 1.28-3.32) and 1.85 (95% CI, 1.26-2.71), respectively. Furthermore, functional analysis revealed that an increase in the number of tandem repeats enhances the binding affinity of ERα. The present study provides the first epidemiological evidence that functional regulatory variants of PTTG1IP were associated with the risk of ER-positive breast cancer, further supporting its relevance as one proto-oncogene in breast cancer.

Genetic variation in the genome-wide predicted estrogen response element-related sequences is associated with breast cancer development

Introduction

Estrogen forms a complex with the estrogen receptor (ER) that binds to estrogen response elements (EREs) in the promoter region of estrogen-responsive genes, regulates their transcription, and consequently mediates physiological or tumorigenic effects. Thus, sequence variants in EREs have the potential to affect the estrogen-ER-ERE interaction. In this study, we examined the hypothesis that genetic variations of EREs are associated with breast cancer development.

Methods

This case-control study involved 815 patients of Asian descent with incident breast cancer and 821 healthy female controls. A total of 13,737 ERE sites in the whole genome predicted by a genome-wide computational algorithm were blasted with single-nucleotide polymorphism (SNP) sequences. Twenty-one SNPs located within 2,000 bp upstream or within introns 1 and 2 of putative genes and with a minor allele frequency greater than 5% were identified and genotyped. Frequencies of SNPs were compared between cases and controls to identify SNPs associated with cancer susceptibility.

Results

A significant combined effect of rs12539530, an ERE SNP in intron 2 of NRCAM which codes for a cell adhesion molecule, and SNPs of ESR1, the gene coding for ER, on breast cancer risk was found. Interestingly, this combined effect was more significant in women who had experienced a longer period of lifetime estrogen exposure, supporting a hormonal etiology of this SNP in breast tumorigenesis.

Conclusions

Our findings provide support for a role of genetic variation in ERE-ESR1 in determining susceptibility of breast cancer development.

Selected estrogen receptor 1 and androgen receptor gene polymorphisms in relation to risk of breast cancer and fibrocystic breast conditions among Chinese women

BACKGROUND

Polymorphisms in sex hormone receptor-encoding genes may alter the activity of sex hormone receptors and thereby affect susceptibility to breast cancer and related outcomes.

METHODS

In a case-control study of women from Shanghai, China, we examined the risk of breast cancer and fibrocystic breast conditions associated with the ESR1 PvuII (rs2234693) and XbaI (rs9340799) and AR CAG repeat ((CAG)(n)) and GGC repeat ((GGC)(n)) polymorphisms among 614 women with breast cancer, 467 women with fibrocystic conditions, and 879 women without breast disease. We also evaluated whether risk differed by the presence/absence of proliferative changes (in the extratumoral epithelium or fibrocystic lesion), menopausal status, or body mass index (BMI). Age-adjusted odds ratios (ORs) and 95% confidence intervals (95% CI) were calculated using logistic regression.

RESULTS

Only associations with AR (CAG)(n) and (GGC)(n) genotypes were detected. Allocating AR (CAG)(n) genotypes into six categories, with the (CAG)(22-24)/(CAG)(22-24) genotype category designated as the reference group, the (CAG)(>24)/(CAG)(>24) genotype category was associated with an increased risk of fibrocystic breast conditions (OR, 1.8; 95% CI, 1.1-3.0). Relative to the AR (GGC)(17)/(GGC)(17) genotype, the (GGC)(17)/(GGC)(14) genotype was associated with elevated risks of incident breast cancer (OR, 2.6; 95% CI, 1.3-5.4) and fibrocystic conditions (OR, 2.3; 95% CI, 1.1-4.5). Results did not differ according to proliferation status, menopausal status, or BMI.

CONCLUSION

Although these data lend support for a link between AR variation and breast disease development, given the low frequency of the putative risk-conferring genotypes and other constraints, further confirmation of our results is needed.