Genetic polymorphisms in estrogen-related genes and the risk of breast cancer among Han Chinese women

Unraveling the molecular significance of CYP1A2 (rs762551; c.-9-154 C>A) genetic variant on breast carcinoma susceptibility: Insights from case-control study and meta-analysis

BACKGROUND

The human cytochrome P450 (CYP) superfamily encompasses different categories of isoenzymes that contribute to multiple metabolic processes involving drug detoxification, cellular signaling, and the proliferation of malignant tissues. Using genetic technology, customized bioinformatic analysis, and meta-analysis design, the main goal of this study was to identify the association between the CYP1A2*rs762551 variant and the susceptibility to breast carcinoma (BRCA).

METHODS

The case-control study was conducted based on 104 BRCA women and 102 healthy controls. Using the TaqMan allelic discrimination assay, the CYP1A2 (rs762551; c.-9-154 C>A) variant was genotyped. Bioinformatic frameworks and logistic regression analysis were used to assess the involvement of this genetic variant in BRCA development. A meta-analysis design was accomplished based on our case-control study and other previously published records. Publication bias, heterogeneity between studies, and trial sequential analysis (TSA) were analyzed.

RESULTS

The CYP1A2*rs762551 variant conferred protection against BRCA development under allelic (OR = 0.48, p-value < 0.001), dominant (OR = 0.34, p-value < 0.001), and recessive (OR = 0.44, p-value = 0.011) models. However, this intronic variant was correlated with a decreased risk of BRCA among late-onset menopause women compared to other cases. Bioinformatic analysis confirmed that this genetic variant has a functional impact on the progression of tumorgenesis. Moreover, this meta-analysis design included 12922 BRCA women and 15603 healthy controls. Our findings disclosed the contribution of the CYP1A2*rs762551 variant with protection against cancer development among Caucasian females under allelic (OR = 0.75, p-value = 0.025), and dominant (OR = 0.58, p-value = 0.015) models.

CONCLUSIONS

This case-control study confirmed the contribution of the CYP1A2*rs762551 variant with decreased risk of BRCA development among Egyptian subjects. Moreover, BRCA women with late-onset menopause conferred protection against cancer progression compared to other subjects. Our findings identified that this meta-analysis design achieved protection against BRCA development among Caucasian women compared to other ethnicities.

The CYP19A1 rs700519 Polymorphism and Breast Cancer Susceptibility in China: A Case-Control Study and Updated Meta-Analysis

Objective: Breast cancer (BC), the most prevalent cancer in women, has been associated with several genetic factors, including the CYP19A1 rs700519 polymorphism; however, the conclusions have not been consistent. This case-control study and meta-analysis aimed to further assess the relationship between the CYP19A1 rs700519 polymorphism and BC susceptibility. Materials and Methods: We conducted a case-control study to assess the relationship of the CYP19A1 rs700519 polymorphism with the risk and prognosis of BC. Subsequently, we performed a meta-analysis of the case-control studies. Results: In the case-control study, we found a significant negative relationship between the rs700519 AA genotype and risk (χ² = 7.503, p < 0.01) and disease-free survival rates (hazard rate = 0.400, 95% confidence interval [CI] = 0.181-0.883, p < 0.01) of patients with BC, especially in postmenopausal hormone receptor-positive (HR⁺) patients. Nine case-control studies were included in the meta-analysis. The CYP19A1 rs700519 polymorphism was significantly associated with BC susceptibility in the dominant (odds ratio [OR] = 0.95, 95% CI = 0.90-1.00, p = 0.05) and allelic models (OR = 0.84, 95% CI = 0.75-0.93, p < 0.01), but not in the recessive model. Sensitivity analysis revealed that the study results were stable, whereas the funnel plot revealed some publication bias. Conclusions: The CYP19A1 rs700519 polymorphism is related to breast tumorigenesis.

The CYP19A1 (TTTA)n Repeat Polymorphism May Affect the Prostate Cancer Risk: Evidence from a Meta-Analysis

Abnormal aromatase (CYP19A1) expression may participate in prostate cancer (PCa) carcinogenesis. However, the results of studies on the CYP19A1 gene polymorphisms and PCa are conflicting. This meta-analysis aimed to systematically evaluate the associations between the CYP19A1 Arg264Cys polymorphism and the (TTTA)n repeat polymorphism and PCa. Electronic databases (PubMed, EmBase, ScienceDirect, and Cochrane Library) were comprehensively searched to identify eligible studies. The strength of the association between the Arg264Cys polymorphism and PCa was assessed by pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) in allelic, dominant, recessive, homozygous, and heterozygous genetic models. To analyze the impact of the (TTTA)n repeat polymorphism, we sequentially took the N-repeat allele (where N equals 7,8,10,11,12, and 13) as the minor allele and the sum of all the other alleles as the major allele. The ORs and 95% CIs were calculated in the allelic model; this analysis was performed individually for each repeat number. Pooled estimates of nine studies addressing the Arg264Cys polymorphism indicated that this polymorphism was not associated with PCa risk in the overall population or in the Caucasian or Asian subgroups. The 8-repeat allele in the (TTTA)n repeat polymorphism increased PCa risk in the overall population (OR = 1.34, 95% CI = 1.14-1.58, p = .001) and in the subgroup with population-based (PB) controls (OR = 1.41, 95% CI = 1.13-1.74, p = .002) as well as in the subgroup using capillary electrophoresis to identify this polymorphism (OR = 1.34, 95% CI = 1.09-1.65, p = .006).The meta-analysis indicated that the CYP19A1 (TTTA)n repeat polymorphism, but not the Arg264Cys polymorphism, may affect PCa risk.

The impact of CYP19A1 variants and haplotypes on breast cancer risk, clinicopathological features and prognosis

Background

Different genetic variants in hormone‐regulating pathways have been identified to influence the risk of breast cancer. This study aimed to evaluate the association of CYP19A1 rs10046 and rs700519 polymorphisms with the risk, clinicopathological factors and prognosis of breast cancer.

Methods

In a case‐control study, rs10046 and rs700519 polymorphisms were genotyped using ARMS‐PCR and high‐resolution melting (HRM), respectively, in a total of 702 females. Statistical analysis and evaluation of haplotypes and linkage disequilibrium were performed using SPSS v16, PHASE and 2LD.

Results

Although no association of rs700519 with breast cancer was observed, rs10046 in different genetic models as well as C‐C/C‐T and C‐C/C‐C diplotypes, revealed the association with the risk of breast cancer (p < 0.05). Moreover, the rs700519‐C allele was shown to be associated with longer overall survival. In contrast, the T‐T haplotype conferred s a shorter overall survival. rs700519‐C allele was also significantly associated with menarche age.

Conclusion

Based on the identified independent association between CYP19A1 diplotypes and rs700519‐C allele with the risk and prognosis of the disease, the gene region and its genetic variants may have a diagnostic and prognostic role in breast cancer development. Further confirmation using other variants in this locus can validate these findings.

A Review of the Epidemiology of Breast Cancer in Asia: Focus on Risk Factors

Background and Aim:

Breast cancer is the most prevalent cancer in women. To date, regional differences in breast cancer risk factors have not been identified. The aim of our review was to gain a better understanding of the role of risk factors in women with breast cancer in Asia.

Methods:

We conducted a PubMed search on 15 March 2016, for journal articles published in English between 2011 and 2016, which reported data for human subjects in Asia with a diagnosis of breast cancer. Search terms included breast neoplasm, epidemiology, Asia, prevalence, incidence, risk and cost of illness. Studies of any design were included, except for review articles and meta-analyses, which were excluded to avoid duplication of data. No exclusions were made based on breast cancer treatment. We reported the results using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines.

Results:

A total of 776 abstracts were retrieved. After screening against the eligibility criteria, 562 abstracts were excluded. The remaining 214 abstracts, which were published between 2013 and 2015, were included in this review. Results were summarized and reported under three categories: incidence, prevalence or outcomes for breast cancer in Asia; modifiable risk factors; and non-modifiable risk factors. We found that the increased risk of breast cancer among participants from Asia was associated with older age, family history of breast cancer, early menarche, late menopause, high body mass index, being obese or overweight, exposure to tobacco smoke, and high dietary intake of fats or fatty foods. In contrast, intake of dietary fruits, vegetables, and plant- and soy-based products was associated with a decreased breast cancer risk. While based on limited data, when compared to women from the United States, women from Asia had a decreased risk of breast cancer.

Conclusions:

This review of 214 abstracts of studies in Asia, published between 2013 and 2015, confirmed the relevance of known non-modifiable and modifiable risk factors for women with breast cancer.

SNHG1 Long Noncoding RNA is Potentially Up-Regulated in Colorectal Adenocarcinoma

Colorectal cancer (CRC) is one of the most common types of cancer worldwide. However, the molecular mechanisms involved in CRC initiation and progression is remained to be unknown. It seems that lncRNAs, as the main and lengthy functional transcripts of the genome, have important roles in different cancers such as CRC. CRC-related lncRNAs are reported to be involved in diverse molecular processes such as metastasis, invasion, cell proliferation, and apoptosis. This study was aimed to analyse the expression level of lncRNA SNHG1 in colorectal adenocarcinoma and normal tissues. We performed an in silico analysis on a large cohort and confirmed the results by experimental analysis of clinical samples through real-time PCR. Our findings demonstrated that that SNHG1 is potentially overexpressed in tumor tissues compared with adjacent normal tissues. The expression level of SNHG1 was shown to be potentially associated with clinicopathological features of tumors. The current study suggests the potential role of SNHG1 in colon cancer progression.

Estrogen receptors genotypes and canine mammary neoplasia

BACKGROUND

Estrogens are essential for the development and proper function of several hormone-dependent organs. There are, however, several lines of evidence associating estrogens with mammary carcinogenesis. A marked individual genetic variability concerning estrogens biosynthesis, metabolism and mechanism of action was recognized and associated with human breast cancer susceptibility, clinical features and progression. Although some genetic variations in canine ESR1 gene were reported, their influence in clinicopathological features and progression of canine mammary tumors has not been fully evaluated. This study aims to assess the influence of SNPs in ESR1 gene (rs397512133, rs397510462, rs851327560, rs397510612, rs852887655, rs852684753 and rs852398698) in canine mammary tumors characteristics and progression. A group of 155 non-neutered bitches with mammary tumors was included in the study. Follow-up information was assessed 24 months after surgery.

RESULTS

Genetic profiles associated with a later onset of mammary tumors and less aggressive clinicopathological features, namely smaller tumor size (≤ 3 cm) with extensive tubular differentiation and low canine-adapted prognostic index (vet-NPI), were identified in this study.

CONCLUSIONS

Our data suggest that the ESR1 genetic profile may help on the decision regarding the selection of individual tailored preventive measures against canine mammary tumors development, such as early neutering.

Association of CYP gene polymorphisms with breast cancer risk and prognostic factors in the Jordanian population

Background

Single nucleotide polymorphisms (SNPs) in several CYP genes have been associated with altered breast cancer (BC) risk in different populations. Despite this, there is a dearth of information on the roles of these SNPs in Jordanian BC patients. Therefore, this study aims to determine if there is any single nucleotide polymorphism (SNP) within CYP19A1, CYP2C19, CYP2C9, CYP1B1, CYP3A4, and CYP1A2 genes associated with BC in the Jordanian population. In addition, this work investigates the association between selected BC prognostic factors and variants of the aforementioned CYP candidate genes.

Methods

Blood samples were withdrawn from 221 BC patients and 218 healthy volunteers recruited from the Jordanian population. Genomic DNA was withdrawn and, after quantification and quality control, was genotyped using the Sequenom MassARRAY® system (iPLEX GOLD). Statistical analysis was then carried out to assess allelic and genotypic frequencies as well as genetic association between cases and controls.

Results

The CYP19A1 SNP rs7176005 (p < 0.0045) and the CYP1A2 SNP rs762551 (p = 0.004) were significantly associated with BC risk. However, no such association was found for the screened SNPs of the CYP2C9, CYP1B1, CYP2C19 and CYP3A4 genes. Regarding the prognostic factors of BC, several of the screened SNPs were associated with different pathological and clinical features.

Conclusions

Certain CYP genes, particularly CYP19A1 and CYP1A2, were associated with BC risk and development in the Jordanian population.

Genetic polymorphisms of estrogen receptor genes are associated with breast cancer susceptibility in Chinese women

Background

Estrogen exposure is a widely known risk factor for BC. And the interaction of estrogen with estrogen receptor (ER) plays an important role in breast cancer development. This case-control study aims to assess the association of genetic polymorphisms in the estrogen receptor genes with breast cancer (BC) susceptibility in Chinese Han women.

Methods

Four polymorphisms (rs2881766, rs9383951, rs9340799 in ESR1 and rs3020449 in ESR2) were genotyped in 459 patients and 549 healthy controls using the Sequenom MassARRAY method. Odds ratio (OR) and 95% confidence intervals (95% CI) were calculated to evaluate the associations. False-positive report probability (FPRP) was utilized to examine the noteworthiness of significant findings.

Results

We observed that rs2881766 was associated with a decreased BC risk (GG vs. TT: OR = 0.63, 95% CI = 0.44-0.91; GG vs. TT/GT: OR = 0.68, 95% CI = 0.49-0.95), while rs3020449 was associated with an increased risk of BC (CT vs. TT: OR = 1.58, 95% CI = 1.21-2.06; CT/CC vs. TT: OR = 1.54, 95% CI = 1.20-1.98; TT/CC vs. CT: OR = 1.48, 95% CI = 1.15-1.90). The other two polymorphisms have no relation with BC susceptibility. In addition, rs2881766 was correlated with lymph node metastasis and ER expression, and rs3020449 was related to tumor size, histological grade and ER expression. The values of false-positive report probability indicated that the significant associations of BC risk with both rs2881766 and rs3020449 were noteworthy.

Conclusions

Our study suggests that polymorphisms rs2881766 and rs3020449 in estrogen receptor genes were associated with BC susceptibility as well as clinical features in Chinese women. These findings need further validation in a large population.

Association between ERα gene Pvu II polymorphism and breast cancer susceptibility: A meta-analysis

BACKGROUND

Estrogen has played an important role in the development of breast cancer. ER-α PvuII gene polymorphism is in close association with the occurrence risk of breast cancer, but no consensus has been achieved currently.

METHODS

PubMed, Embase, China National Knowledge Infrastructure (CNKI) database, Wanfang database, and VIP database were retrieved to collect the case-control studies on association between ERα gene Pvu II polymorphism and breast cancer risk published before September 1, 2017. Newcastle-Ottawa Scale (NOS) was used to assess the quality of the literatures, Stata 14.0 software was applied for meta-analysis, and the pooled odds ratio (OR) and 95% confidence interval (95% CI) were calculated. The subgroup analysis was performed to assess the confounding factors, followed by assessment of publication bias and sensitivity analysis.

RESULTS

A total of 26 studies were enrolled in the analysis based on inclusion criteria, which included 15,360 patients and 26,423 controls. The results demonstrated that ERα gene Pvu II polymorphism was in significant association with the decrease of breast cancer risk in 3 genetic models (C vs T, OR = 0.962, 95% CI = 0.933-0.992, P = .012; CC vs TT, OR = 0.911, 95% CI = 0.856-0.969, P = .003; CC vs TT/CT, OR = 0.923, 95% CI = 0.874-0.975, P = .004). Subgroup analysis was conducted on the basis of ethnicity and source of controls, whose results illustrated that ERα gene Pvu II polymorphism was in significant association with the decrease of breast cancer risk in Asians rather than in Caucasians (CC vs TT, OR = 0.862, 95% CI = 0.750-0.922, P = .038; CC vs TT/CT, OR = 0.851, 95% CI = 0.755-0.959, P = .008). In population-based subgroup rather than in hospital-based subgroup, ERα gene Pvu II polymorphism was in significant association with the decrease of breast cancer risk in the allele model, homozygous model, dominant model, and recessive model (C vs T, OR = 0.943, 95% CI = 0.911-0.977, P = .001; CC vs TT, OR = 0.878, 95% CI = 0.817-0.944, P = .000; CC/CT vs TT, OR = 0.936, 95% CI = 0.881-0.994, P = .031; CC vs TT/CT, OR = 0.902, 95% CI = 0.847-0.960, P = .001).

CONCLUSION

ERα gene Pvu II polymorphism exerts an important function in the progression of breast cancer.

Associations of Genetic Variants at Nongenic Susceptibility Loci with Breast Cancer Risk and Heterogeneity by Tumor Subtype in Southern Han Chinese Women

Current understanding of cancer genomes is mainly “gene centric.” However, GWAS have identified some nongenic breast cancer susceptibility loci. Validation studies showed inconsistent results among different populations. To further explore this inconsistency and to investigate associations by intrinsic subtype (Luminal-A, Luminal-B, ER−&PR−&HER2+, and triple negative) among Southern Han Chinese women, we genotyped five nongenic polymorphisms (2q35: rs13387042, 5p12: rs981782 and rs4415084, and 8q24: rs1562430 and rs13281615) using MassARRAY IPLEX platform in 609 patients and 882 controls. Significant associations with breast cancer were observed for rs13387042 and rs4415084 with OR (95% CI) per-allele 1.29 (1.00–1.66) and 0.83 (0.71–0.97), respectively. In subtype specific analysis, rs13387042 (per-allele adjusted OR = 1.36, 95% CI = 1.00–1.87) and rs4415084 (per-allele adjusted OR = 0.82, 95% CI = 0.66–1.00) showed slightly significant association with Luminal-A subtype; however, only rs13387042 was associated with ER−&PR−&HER2+ tumors (per-allele adjusted OR = 1.55, 95% CI = 1.00–2.40), and none of them were linked to Luminal-B and triple negative subtype. Collectively, nongenic SNPs were heterogeneous according to the intrinsic subtype. Further studies with larger datasets along with intrinsic subtype categorization should explore and confirm the role of these variants in increasing breast cancer risk.

Distinct microbiological signatures associated with triple negative breast cancer

Infectious agents are the third highest human cancer risk factor and may have a greater role in the origin and/or progression of cancers, and related pathogenesis. Thus, knowing the specific viruses and microbial agents associated with a cancer type may provide insights into cause, diagnosis and treatment. We utilized a pan-pathogen array technology to identify the microbial signatures associated with triple negative breast cancer (TNBC). This technology detects low copy number and fragmented genomes extracted from formalin-fixed paraffin embedded archival tissues. The results, validated by PCR and sequencing, define a microbial signature present in TNBC tissue which was underrepresented in normal tissue. Hierarchical clustering analysis displayed two broad microbial signatures, one prevalent in bacteria and parasites and one prevalent in viruses. These signatures demonstrate a new paradigm in our understanding of the link between microorganisms and cancer, as causative or commensal in the tumor microenvironment and provide new diagnostic potential.