Genetic variants in interleukin genes are associated with breast cancer risk and survival in a genetically admixed population: the Breast Cancer Health Disparities Study

Expression and clinical significance of interleukin-6 pathway in cholangiocarcinoma

Background

Cholangiocarcinoma (CCA) is a typical inflammation-induced malignancy, and elevated serum interleukin-6 (IL-6) levels have been reported to be linked to the onset and progression of CCA. We aim to investigate the potential prognostic value of the IL-6 pathway for CCA.

Methods

We detected the expressions of IL-6, IL-6R, glycoprotein (gp130), C-reactive protein (CRP), Janus kinase 2 (JAK2), and signal transducer and activator of transcription 3 (STAT3) in CCA tissue microarray using multiplex immunofluorescence. Furthermore, the clinical associations and prognostic values were assessed. Finally, single-cell transcriptome analysis was performed to evaluate the expression level of IL-6 pathway genes in CCA.

Results

The results revealed that the expression of IL-6 was lower, while the expression of STAT3 was higher in tumor tissues compared to normal tissues. Especially in tumor microenvironment, the expression of IL-6 pathway genes was generally downregulated. Importantly, gp130 was strongly correlated with JAK2 in tumor tissues, while it was moderately correlated with JAK2 in normal tissue. Although none of the gene expressions were directly associated with overall survival and disease-free survival, our study found that IL-6, IL-6R, CRP, gp130, and JAK2 were inversely correlated with vascular invasion, which is a risk factor for poor prognosis in patients with CCA.

Conclusion

The findings from this study suggest that the IL-6 signaling pathway may have a potential prognostic value for CCA. Further investigation is needed to understand the underlying molecular mechanisms of the IL-6 pathway in CCA.

CRP, IL-1α, IL-1β, and IL-6 levels and the risk of breast cancer: a two-sample Mendelian randomization study

Epidemiological studies have reported a positive association between chronic inflammation and cancer risk. However, the causal association between chronic inflammation and breast cancer (BC) risk remains unclear. Here, we performed a Mendelian randomization study to investigate the etiological role of chronic inflammation in BC risk. We acquired data regarding C-reactive protein (CRP), interleukin (IL)-1a, IL-1b, and IL-6 expression and BC related to single nucleotide polymorphisms (SNPs) from two larger consortia (the genome-wide association studies and the Breast Cancer Association Consortium). Next, we conducted the two-sample Mendelian randomization study to investigate the relationship of the abovementioned inflammatory factors with the incidence of BC. We found that genetically predicted CRP, IL-6, and IL-1a levels did not increase BC incidence (odds ratio (OR)CRP 1.06, 95% confidence interval (CI) 0.98-1.12, P = 0.2059, ORIL-6 1.05, 95% CI 0.95-1.16, P = 0.3297 and ORIL-1a 1.01, 95% CI 0.99-1.03, P = 0.2167). However, in subgroup analysis, genetically predicted IL-1b levels increased ER + BC incidence (OR 1.15, 95% CI 1.03-1.27, P = 0.0088). Our study suggested that genetically predicted IL-1b levels were found to increase ER + BC susceptibility. However, due to the support of only one SNP, heterogeneity and pleiotropy tests cannot be performed, which deserves further research.

Analysis of Interleukin-6 Gene Variants (rs1800795, rs1800796, rs1554606, rs1800797, rs2069840, rs12700386, and rs2069861) as Prognostic Markers in Breast Cancer: A Systematic Review, Meta-Analysis, and Network Analysis

Interleukin-6 (IL-6) has obviously tumor-promoting and tumor-inhibitory effects and can induce an epithelial-mesenchymal transition phenotype in human breast cancer (BC) cells and implicate its potential to promote BC metastasis. Herein, we aimed to evaluate the association of IL-6 variants (rs1800795, rs1800796, rs1554606, rs1800797, rs2069840, rs12700386, and rs2069861) with the susceptibility to BC. The databases of PubMed/Medline, Web of Science, Scopus, and Cochrane Library were searched until December 19, 2022, without any restrictions. The quality assessment of each study was performed based on the Newcastle-Ottawa Scale tool. The Review Manager 5.3 software presented the effect sizes including odds ratio (OR) along with a 95% confidence interval (CI). Both publication bias and sensitivity analyses were carried out by the Comprehensive Meta-Analysis version 2.0 software. A total of 2,508 records were identified among databases and at last, 27 articles were entered into the meta-analysis. Seven polymorphisms of IL-6 were entered into the analyses. Just rs1800797 polymorphism in the dominant model (OR = 1.51; 95% CI = 1.15-2.00; P = 0.003) and rs2069840 polymorphism in heterozygous (OR = 0.89; 95% CI = 0.81-0.97; P = 0.008) and dominant (OR = 0.91; 95% CI = 0.84-0.99; P = 0.02) models had a significant association with the BC risk. In conclusion, among 7 polymorphisms and despite a few included cases, the present meta-analysis recommended that the AA+GA genotype of rs1800797 polymorphism had a significantly elevated risk and the GC and the CC+GC genotypes of rs2069840 polymorphism had a protective role in the BC patients.

Comprehensive analysis of autophagy associated genes and immune infiltrates in cervical cancer

Objectives

Cervical cancer (CC) is the most common gynecological malignant tumor and the fourth leading cause of cancer-related death in women. The progression of CC is significantly affected by autophagy. Our objective was to use bioinformatics analysis to explore the expression, prognostic significance, and immune infiltration of autophagy-related genes in CC.

Materials and Methods

We identified a set of autophagy-related differentially expressed genes (ARDEGs) from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. ARDEGs were further validated by The Human Protein Atlas (HPA), GSE52903, and GSE39001 dataset. Hub genes were found by the STRING network and Cytoscape. We performed Gene Set Enrichment Analysis (GSEA), Gene ontology analysis (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, and immune infiltration analysis to further understand the functions of the hub genes. Kaplan-Meier (K-M) and receiver operating characteristic (ROC) were used to check the hub genes.

Results

A total of 10 up-regulated (CXCR4, BAX, SPHK1, EIF2AK2, TBK1, TNFSF10, ITGB4, CDKN2A, IL24, and BIRC5) and 19 down-regulated (PINK1, ATG16L2, ATG4D, IKBKE, MLST8, MAPK3, ERBB2, ULK3, TP53INP2, MTMR14, BNIP3, FOS, CCL2, FAS, CAPNS1, HSPB8, PTK6, FKBP1B , and DNAJB1) ARDEGs were identified. The ARDEGs were enriched in cell growth, apoptosis, human papillomavirus infection, and cytokine-mediated. Then, we found that low expression of MAPK3 was associated with poor prognosis in CC patients and was significantly enriched in immune pathways. In addition, the expression of MAPK3 was significantly positively correlated with the infiltration levels of macrophages, B cells, mast cell activation, and cancer-associated fibroblasts. Furthermore, MAPK3 was positively correlated with LGALS9, and negatively correlated with CTLA4 and CD40.

Conclusion

Our results show that MAPK3 can be used as a new prognostic biomarker to predict the prognosis of patients with CC.

Leveraging epigenomes and three-dimensional genome organization for interpreting regulatory variation

Understanding the impact of regulatory variants on complex phenotypes is a significant challenge because the genes and pathways that are targeted by such variants and the cell type context in which regulatory variants operate are typically unknown. Cell-type-specific long-range regulatory interactions that occur between a distal regulatory sequence and a gene offer a powerful framework for examining the impact of regulatory variants on complex phenotypes. However, high-resolution maps of such long-range interactions are available only for a handful of cell types. Furthermore, identifying specific gene subnetworks or pathways that are targeted by a set of variants is a significant challenge. We have developed L-HiC-Reg, a Random Forests regression method to predict high-resolution contact counts in new cell types, and a network-based framework to identify candidate cell-type-specific gene networks targeted by a set of variants from a genome-wide association study (GWAS). We applied our approach to predict interactions in 55 Roadmap Epigenomics Mapping Consortium cell types, which we used to interpret regulatory single nucleotide polymorphisms (SNPs) in the NHGRI-EBI GWAS catalogue. Using our approach, we performed an in-depth characterization of fifteen different phenotypes including schizophrenia, coronary artery disease (CAD) and Crohn's disease. We found differentially wired subnetworks consisting of known as well as novel gene targets of regulatory SNPs. Taken together, our compendium of interactions and the associated network-based analysis pipeline leverages long-range regulatory interactions to examine the context-specific impact of regulatory variation in complex phenotypes.

Effect of mild intermittent cold stimulation on thymus immune function in broilers

This study aims to assess the effect of intermittent and mild cold stimulation (IMCS) on thymus function and the ability of 1-day-old male Ross 308 broilers to withstand cold. Four hundred broilers were reared under normal and mild cold temperatures at 3°C below the normal feeding temperature and were subjected to acute cold stress (ACS) at 10°C on d 50 at 7 am for 6 h, 12 h, and 24 h. We determined the expression levels of toll-like receptors (TLRs), cytokines and avian β-defencins (AvBDs), encoding genes in thymus of broilers at 22, 36, 43, and 50 d of age, and the serum ACTH and cortisol (CORT) levels at 50 d of age. At D22 and D36, the mRNA expression levels of TLRs and AvBDs genes in CS groups were generally significantly decreased (P < 0.05). The lowest expression levels were found in birds submitted to intermittent and mild cold stimulation training for 5 h (CS5 group) on d 22 and 36 of development (P < 0.05). At D43 and D49 after IMCS, mRNA expression levels of most TLRs and AvBDs were significantly lower than those in CC group (P < 0.05), and that mRNA expression levels of all TLRs and most AvBDs in CS5 group had the same change trend with age as those in CC group (P > 0.05). At D22 and D36, mRNA expression levels of different cytokines in each CS groups were different (P < 0.05). mRNA expression levels of IL-2, IL-4, IL-6, IL-8, IL-17, and IFN-α all reached the highest values in the CS5 group at D36 (P < 0.05). The levels of ACTH and CORT in all IMCS-treated birds changed in varying degrees after ACS, but there was no significant change in CS5 group (P > 0.05). Collectively, different cold stimulation schemes could modulate thymus immune function of broilers by maintaining homeostasis and enhancing cold resistance. In particular, the optimal cold adaptation scheme was at 3°C below the conventional feeding temperature for 5 h.

Mutation of Hashimoto’s Thyroiditis and Papillary Thyroid Carcinoma Related Genes and the Screening of Candidate Genes

Clinical studies have shown similarities in the genetic background and biological functional characteristics between Hashimoto’s thyroiditis (HT) and papillary thyroid carcinoma (PTC), and that HT may increase risks of PTC. Here, we set to determine the gene expression specificity of HT and PTC by screening related genes or co-expressed genes and exploring their genetic correlation. Referencing the Oncomine database, HT-related genes were discovered to be expressed in many different types of thyroid cancer, such as TSHR that is highly expressed in thyroid cancer. An in-depth genetic analysis and verification of 35 cancer and paracancerous tissue pairs from patients with thyroid cancer, and 35 tissues and blood cells pairs from patients with Hashimoto’s thyroiditis was conducted. Gene chip technology research showed that TSHR, BACH2, FOXE1, RNASET2, CTLA4, PTPN22, IL2RA and other HT-related genes were all expressed in PTC, in which TSHR was significantly over-expressed in PTC patients sensitive to radioactive iodine therapy, while BACH2 was significantly under-expressed in these patients. The biologically significant candidate Tag SNP highlighted from HT-related genes was screened by the high-throughput detection method. Somatic mutations in patients with HT and PTC were detected by target region capture technique, and 75 mutations were found in patients with HT and PTC. The upstream regulatory factors of the different genes shared by HT and PTC were analyzed based on Ingenuity Pathway Analysis (IPA), and it was found that HIF-1α and PD-L1 could be used as important upstream regulatory signal molecules. These results provide a basis for screening key diagnostic genes of PTC by highlighting the relationship between some HT-related genes and their polymorphisms in the pathogenesis of PTC.

The IL6-like Cytokine Family: Role and Biomarker Potential in Breast Cancer

IL6-like cytokines are a family of regulators with a complex, pleiotropic role in both the healthy organism, where they regulate immunity and homeostasis, and in different diseases, including cancer. Here we summarise how these cytokines exert their effect through the shared signal transducer IL6ST (gp130) and we review the extensive evidence on the role that different members of this family play in breast cancer. Additionally, we discuss how the different cytokines, their related receptors and downstream effectors, as well as specific polymorphisms in these molecules, can serve as predictive or prognostic biomarkers with the potential for clinical application in breast cancer. Lastly, we also discuss how our increasing understanding of this complex signalling axis presents promising opportunities for the development or repurposing of therapeutic strategies against cancer and, specifically, breast neoplasms.

Characteristics and Role of Neutrophil Extracellular Traps in Asthma

Asthma is a common chronic respiratory disease that affects millions of people worldwide. The incidence of asthma has continued to increase every year. Bronchial asthma involves a variety of cells, including airway inflammatory cells, structural cells, and neutrophils, which have gained more attention because they secrete substances that play an important role in the occurrence and development of asthma. Neutrophil extracellular traps (NETs) are mesh-like structures composed of DNA, histones, and non-histone molecules that can be secreted from neutrophils. NETs can enrich anti-bacterial substances and limit pathogen migration, thus having a protective effect in case of inflammation. However, despite of their anti-inflammatory properties, NETs have been shown to trigger allergic asthma and worsen asthma progression. Here, we provide a systematic review of the roles of NETs in asthma.

Associations of interleukin-4 and interleukin-4 receptor loci with esophageal squamous cell carcinoma susceptibility

Some functional polymorphisms in immune-regulating genes could affect the development of esophageal squamous cell carcinoma (ESCC). We enrolled 721 patients with ESCC and 1,208 healthy controls to explore the roles of rs2227282 (C > G) and rs2243283 (C > G) loci in the interleukin-4 (IL4) gene and rs1801275 loci in the interleukin-4 receptor (IL4R) gene for the occurrence of ESCC. As for IL4, the single nucleotide polymorphism rs2227282 (C > G) conferred an overall decreased risk for ESCC (adjusted P = 0.005, power = 0.816 in GG vs. CC genetic models). A stratification analysis of IL4 rs2227282 (C > G) and rs2243283 (C > G) and IL4R rs1801275 (A > G) loci with the ESCC risk revealed that the IL4 rs2243283 (C > G) polymorphism was a protective factor for the susceptibility to ESCC in some subgroups (women: power = 0.932 in CG vs. CC and 0.956 in CG/GG vs. CC; subjects aged ≥63 years: power = 0.844 in CG/GG vs. CC; never-smokers: power = 0.893 in CG vs. CC and 0.882 in CG/GG vs. CC; never-drinkers: power = 0.904 in CG vs. CC and 0.862 in CG/GG vs. CC). We also investigated the association of IL4 rs2227282 and rs2243283 and IL4R rs1801275 loci with the lymph node status. However, a null relationship was found. In conclusion, the present study highlighted that IL4 rs2227282 (C > G) and rs2243283 (C > G) loci are protective factors for the occurrence of ESCC.

Statistical meta-analysis to investigate the association between the Interleukin-6 (IL-6) gene polymorphisms and cancer risk

A good number of genome-wide association studies (GWAS), including meta-analyses, reported that single nucleotide polymorphisms (SNPs) of the IL-6 gene are significantly associated with various types of cancer risks, though some other studies reported insignificant association with cancers, in the literature. These contradictory results may be due to variations in sample sizes and/or deficiency of statistical modeling. Therefore, an attempt is made to provide a more comprehensive understanding of the association between the IL-6 gene SNPs (rs1800795, rs1800796, rs1800797) and different cancer risks, giving the weight on a large sample size, including different cancer types and appropriate statistical modeling with the meta-dataset. In order to attain a more reliable consensus decision about the association between the IL-6 gene polymorphisms and different cancer risks, in this study, we performed a multi-case statistical meta-analysis based on the collected information of 118 GWAS studies comprising of 50053 cases and 65204 control samples. Results from this Meta-analysis indicated a significant association (p-value < 0.05) of the IL-6 gene rs1800796 polymorphism with an overall increased cancer risk. The subgroup analysis data based on cancer types exhibited significant association (p-value < 0.05) of the rs1800795 polymorphism with an overall increased risk of cervical, liver and prostate cancers; the rs1800796 polymorphism with lung, prostate and stomach cancers; and the rs1800797 polymorphism with cervical cancer. The subgroup analysis of ethnicity data showed a significant association (p-value < 0.05) of an overall cancer risk with the rs1800795 polymorphism for the African and Asian populations, the rs1800796 polymorphism for the Asian only and the rs1800797 polymorphism in the African population. Comparative discussion showed that our multi-case meta-analyses received more support than any previously reported individual meta-analysis about the association between the IL-6 gene polymorphisms and cancer risks. Results from this study, more confidently showed that the IL-6 gene SNPs (rs1800795, rs1800796 and rs1800797) in humans are associated with increased cancer risks. Therefore, these three polymorphisms of the IL-6 gene have the potential to be evaluated as a population based rapid, low-cost PCR prognostic biomarkers for different types of cancers diagnosis and research.

Impact of genetic variants in IL-2RA and IL-2RB on breast cancer risk in Chinese Han women

The expression of IL-2RA and IL-2RB was correlated with breast cancer (BC) progression. However, there is no literature investigating the association of IL-2RA and IL-2RB polymorphisms with BC predisposition among Chinese Han Women. Seven SNPs in IL-2RA and IL-2RB were genotyped by Agena MassARRAY platform among 553 BC patients and 550 healthy controls. Odds ratios (OR) and 95% confidence interval (CI) adjusted for age were calculated for the effect of IL-2RA and IL-2RB variants on BC susceptibility. IL-2RA rs12722498 was a protective factor for BC occurrence (OR = 0.70, p = 0.019), especially in subjects with age ≤ 52 years (OR = 0.55, p = 0.004). IL-2RA rs12569923 (OR = 9.07, p = 0.033), IL-2RB rs2281089 (OR = 0.67, p = 0.043) and rs9607418 (OR = 0.59, p = 0.012) were related to the incidence of estrogen receptor positive (ER +) BC. IL-2RB rs3218264 (OR = 1.38, p = 0.010) and rs9607418 (OR = 0.56, p = 0.009) were associated with the risk of developing progesterone receptor positive (PR +) BC. Rs2281089 (OR = 1.54, p = 0.012) and rs1573673 (OR = 0.72, p = 0.035) were correlated to Ki-67 level. Moreover, IL-2RB rs2281089 (OR = 0.72, p = 0.022) showed a reduced risk of BC metastasis, and IL-2RA rs12722498 (OR = 0.54, p = 0.030) had a lower frequency in BC patients with tumor size > 2 cm. Our study identified the potential effect of genetic variations in IL-2RA and IL-2RB on BC susceptibility and/or BC clinicopathologic indicators among Chinese Han Women.

Immunohistochemical expression of interleukin-17 and hormonal receptors in benign and malignant breast lesions

OBJECTIVES

IL17 is a critical pro-inflammatory cytokine that is involved in inflammation, multidrug resistance and growth persistence pathways in cancer. This study is aiming at studying the expression of IL17 and hormonal receptors expression in benign and malignant breast lesions using immunohistochemical staining methods.

RESULTS

A total of 137 cases of breast lesions were studied, 97 (70.8%) were malignant and 40 (29.2%) were benign cases. Age range for malignant and benign cases were between 26 and 80 years [mean age 50 ± 2 years], and 20 to 70 years [mean age 41 ± 4 years], respectively, Odds ratio = 2.3 [1.78-1.99, 95% CI]. The majority of the histopathological diagnosis of the benign and malignant lesions were 21 (15.3%) fibro-adenomas and 87 (63.5%) invasive ductal carcinoma, respectively. Expression of IL17 and age were insignificantly negatively correlated for both groups; benign cases [r = - 0.054, P value 0.742] and malignant cases [r = - 0.080, P value 0.444]. IL17 expression was showing insignificant association with age group, P value 0.065. IL17 expression showed a statistical significance based on the different histopathological diagnosis, P value 0.035. Expression levels of estrogen, progesterone, and human epidermal receptors were showing insignificant difference among IL17 expression categories, P values 0.678, 0.623, and 0.361, respectively.

The effect of interleukin 10 polymorphisms on breast cancer susceptibility in Han women in Shaanxi Province

Background

Previous studies have reported on several genetic variants related to breast cancer, but a substantial proportion of mutation loci have not yet been identified. In the current study, we aimed to evaluate the association between single nucleotide polymorphisms (SNPs) of interleukin-10 (IL-10) and susceptibility to breast cancer in Shaanxi Han women in China.

Methods

Six SNPs were genotyped in 530 breast cancer patients and 628 healthy women from the First Affiliated Hospital of Xi’an Jiaotong University Hospital. Odds ratios and 95% confidence intervals were calculated by unconditional logistic regression analysis to assess the association between breast cancer risk and polymorphisms of six loci.

Results

Two SNPs, rs3024490 and rs1800871, were found to be significantly different between breast cancer patients and healthy women. These SNPs also increased the risk of breast cancer in co-dominant and dominant models. Moreover, another SNP, rs1554286, was significantly associated with an increased risk of breast cancer in the co-dominant model. Functional assessments indicated that these three variants may influence the expression and transcription factor binding of IL-10.

Conclusions

Our findings suggest that variants of IL-10 may be likelihood risk factors for the development and progression of breast cancer. Future studies should replicate this study and evaluate functional assessments in Chinese Han women and women from other regions.

The -174G>C and -596G>A Polymorphisms Are Not Associated with Circulating IL-6 Levels in Breast Cancer Patients from Jalisco, México

Introduction: Interleukin-6 (IL-6) is a circulating proinflammatory cytokine that fulfills an important role in the survival and proliferation of cancer cells. Overexpression of IL-6, possibly due to the -174G>C and -596G>A polymorphisms in the IL6 gene, has been shown to be related to breast cancer (BC) and a more aggressive course of the disease. Aim: To determine the influence of the -174G>C and -596G>A polymorphisms of the IL6 gene on the circulating levels of IL-6 in BC patients from Jalisco, México. Methodology: Genotyping of the two polymorphisms was carried out on 208 BC patients and 219 healthy controls through polymerase chain reaction-restriction fragment length polymorphism analyses. In addition, the plasma IL-6 concentration levels were measured in the BC patients. Results: There was no significant association between BC and the IL-6 alleles and genotypes (-174G>C, p = 0.276; -596G>A, p = 0.762) under study. Similarly, there were no significant differences in the mean plasma IL-6 concentrations associated with the polymorphisms that were analyzed (-174G>C, p = 0.839; -596G>A, p = 0.848). Conclusions: No evidence was found that the analyzed polymorphisms are associated with the IL-6 expression or concentration in patients suffering from BC from Jalisco, Mexico.

Th17 Cells and IL-17 As Novel Immune Targets in Ovarian Cancer Therapy

Ovarian cancer (OC) is usually diagnosed at an advanced stage and is related with poor prognosis. Despite numerous studies, the pathogenesis of OC is still unknown. Recent studies indicate the role of the immune system in the development and spread of OC. The identification of factors and mechanisms involved in that process and their modulation is crucial for creating effective antitumor therapy. We investigated the potential role of Th17 cells in OC patients (n = 71) by analyzing the frequencies of Th17 cells in three different environments, i.e., peripheral blood (PB), peritoneal fluid (PF), and tissue (Th17 infiltrating cells), and the concentration of IL-17A in plasma and PF of patients in terms of their clinical and prognostic significance. Th17 cells were analyzed by flow cytometry as a percentage of CD4⁺ lymphocytes that expressed intracellular expression of IL-17A. The level of IL-17A in plasma and PF were determined by ELISA. Our results showed accumulation of Th17 cells among tumor-infiltrating CD4⁺ lymphocytes (p < 0.001 in relation to PB). Moreover, the percentage of Th17 cells in both PB and PF of OC patients was significantly lower than that in benign tumors group (n = 35). There were no significant differences in the percentage of Th17 cells in PB, PF, and tissue in relation to clinicopathological characteristics of OC patients and survival. The lower percentage of Th17 cells in the PB and PF of OC patients may promote evasion of host immune response by cancer cells. The concentration of IL-17A in plasma of OC patients was higher (p < 0.0001) than that in both benign tumors and control group (n = 10). The PF IL-17A level in OC patients was higher (p < 0.0001) than that in women with benign ovarian tumors, indicating its synthesis in OC microenvironment. Higher IL-17A level in PF is correlated with longer (median: 36.5 vs. 27 months) survival of OC patients.

Genetic Epidemiology of Breast Cancer in Latin America

The last 10 years witnessed an acceleration of our understanding of what genetic factors underpin the risk of breast cancer. Rare high- and moderate-penetrance variants such as those in the BRCA genes account for a small proportion of the familial risk of breast cancer. Low-penetrance alleles are expected to underlie the remaining heritability. By now, there are about 180 genetic polymorphisms that are associated with risk, most of them of modest effect. In combination, they can be used to identify women at the lowest or highest ends of the risk spectrum, which might lead to more efficient cancer prevention strategies. Most of these variants were discovered in populations of European descent. As a result, we might be failing to discover additional polymorphisms that could explain risk in other groups. This review highlights breast cancer genetic epidemiology studies conducted in Latin America, and summarizes the information that they provide, with special attention to similarities and differences with studies in other populations. It includes studies of common variants, as well as moderate- and high-penetrance variants. In addition, it addresses the gaps that need to be bridged in order to better understand breast cancer genetic risk in Latin America.

Association of Interleukin-1 beta and tumor necrosis factor-alpha genetic polymorphisms with gastric cancer in India

Interleukin 1 beta (IL-1β) and Tumor necrosis factor alpha (TNF-α) are key inflammatory cytokines whose polymorphisms have been correlated with increased susceptibility to gastric cancer (GC). Since geographical and racial differences exist in cancer rates, our study was aimed to evaluate the first possible association of polymorphisms in these genes with GC risk in West Bengal, India. Polymorphisms in IL-1β and TNF-α genes were genotyped in 120 GC patients and 135 healthy individuals. Combined effect of the SNPs in both genes with GC risk was determined through allele dosage analysis (ADA) and the survival data were analyzed by Log Rank Test. The study results revealed that IL-1β rs1143627: T > C, rs16944: C > T (p = 0.001;OR = 1.85; 95% CI 1.30-2.63) and rs1143633: G > A (p < 0.0001; OR = 2.53; 95% CI 1.67-3.83) and TNF-α rs1800630: C > A, rs1799964: T > C (p < 0.0001; OR = 2.31; 95% CI 1.54-3.46) polymorphisms significantly contributed toward GC risk. Moreover, ADA showed that carriage of 7 "effective" risk alleles conferred a risk of almost 10-fold in comparison to individuals carrying less than 3 "effective" risk alleles. Our survival analysis also indicated a significant association between IL-1β rs1143627: T > C and rs16944: C > T and patient survivability. The presence of H. pylori enhanced the risk in individuals with IL-1β rs1143627:CC and rs16944:TT genotypes. Further, meta-analysis revealed significant association of IL-1β rs1143627: T > C (p = 0.026; OR = 4.165; 95% CI 1.18-14.65) and rs16944: C > T (p = 0.01; OR = 5.49; 95% CI 1.48-20.37) in presence of H. pylori with gastric cancer in Asian population though no significant difference (p > 0.05) was found when compared to absence of H. pylori Environ. Mol. Mutagen. 59:653-667, 2018. © 2018 Wiley Periodicals, Inc.

Interleukin‑17A and heparanase promote angiogenesis and cell proliferation and invasion in cervical cancer

Interleukin‑17A (IL‑17A) is a CD4 T-cell-derived pro-inflammatory cytokine that is involved in human cervical tumorigenesis. Heparanase (HPSE) is an endo-glycosidase expressed in mammals, which has been confirmed to be associated with cervical cancer invasion. In the present study, it was hypothesized that IL‑17A and HPSE are key proteins promoting tumor angiogenesis and cell proliferation and invasion in cervical cancer. The expression of IL‑17A and HPSE in cervical cancer tissues was detected by immunohistochemical staining. In addition, the expression of IL‑17A and HPSE was down- and upregulated via RNAi and human recombinant proteins, and MTT and Transwell assays were performed to examine cervical cancer cell proliferation and invasion, respectively. Flow cytometry analysis was also performed to detect cell cycle distribution, and the levels of target mRNA and protein were evaluated by reverse transcription-quantitative polymerase chain reaction and western blotting, respectively. IL‑17A and HPSE were highly expressed in cervical cancer tissues, and microvessel density was notably higher in the IL‑17A-positive group. IL‑17A and/or HPSE recombinant protein promoted the proliferation and invasion of cervical cancer cells, increased the proportion of cells in the G2/M phase, and enhanced the mRNA and protein expression of human papillomavirus E6, P53, vascular endothelial growth factor and CD31, whereas downregulation of IL‑17A and/or HPSE exerted the opposite effects. Furthermore, downregulation of IL‑17A and/or HPSE was found to inhibit the expression of nuclear factor (NF)-κB P65. In summary, IL‑17A and HPSE may promote tumor angiogenesis and cell proliferation and invasion in cervical cancer, possibly via the NF-κB signaling pathway. These findings may lead to the identification of new diagnostic markers and therapeutic targets.

Associations of interleukin-6 gene polymorphisms with cancer risk: Evidence based on 49,408 cancer cases and 61,790 controls

Many molecular epidemiologic studies have shown that interleukin-6 (IL-6) polymorphisms are significantly associated with susceptibility for various cancers. However, the conclusions of these studies are inconsistent. The purpose of the present study was to explore the association between three common IL-6 loci (rs1800795, rs1800796, and rs1800797) and the risk for various cancers. We systematically searched the PubMed, Web of Science, Wanfang and China national knowledge infrastructure (CNKI) databases for relevant publications and obtained 108 eligible studies, involving 49,408 cancer patients and 61,790 cancer-free controls. Odds ratio (OR), 95% confidence interval (CI), and false positive reporting probability (FPRP) were used to evaluate cancer risk. All statistical analyses were performed using the R software meta package. We observed a non-significant association between rs1800795 and overall cancer risk, while rs1800797 was found to have a false positive association with overall risk of cancer. Subgroup analyses of rs1800797 also suggested non-significant association and rs1800795 played a protective role in liver cancer. Rs1800796 was found to be associated with overall cancer risk, particularly in Asian patients and those with prostate cancer. These findings provide evidence that IL-6 polymorphisms may affect cancer risk.

Literature review of data-based models for identification of factors associated with racial disparities in breast cancer mortality

In the United States, early detection methods have contributed to the reduction of overall breast cancer mortality but this pattern has not been observed uniformly across all racial groups. A vast body of research literature shows a set of health care, socio-economic, biological, physical, and behavioural factors influencing the mortality disparity. In this paper, we review the modelling frameworks, statistical tests, and databases used in understanding influential factors, and we discuss the factors documented in the modelling literature. Our findings suggest that disparities research relies on conventional modelling and statistical tools for quantitative analysis, and there exist opportunities to implement data-based modelling frameworks for (1) exploring mechanisms triggering disparities, (2) increasing the collection of behavioural data, and (3) monitoring factors associated with the mortality disparity across time.

Genomic Disparities in Breast Cancer Among Latinas

BACKGROUND

Breast cancer is the most common cancer diagnosed among Latinas in the United States and the leading cause of cancer-related death among this population. Latinas tend to be diagnosed at a later stage and have worse prognostic features than their non-Hispanic white counterparts. Genetic and genomic factors may contribute to observed breast cancer health disparities in Latinas.

METHODS

We provide a landscape of our current understanding and the existing gaps that need to be filled across the cancer prevention and control continuum.

RESULTS

We summarize available data on mutations in high and moderate penetrance genes for inherited risk of breast cancer and the associated literature on disparities in awareness of and uptake of genetic counseling and testing in Latina populations. We also discuss common genetic polymorphisms and risk of breast cancer in Latinas. In the treatment setting, we examine tumor genomics and pharmacogenomics in Latina patients with breast cancer.

CONCLUSIONS

As the US population continues to diversify, extending genetic and genomic research into this underserved and understudied population is critical. By understanding the risk of breast cancer among ethnically diverse populations, we will be better positioned to make treatment advancements for earlier stages of cancer, identify more effective and ideally less toxic treatment regimens, and increase rates of survival.

Associations of genotypes and haplotypes of IL-17 with risk of gastric cancer in an eastern Chinese population

Interleukin-17 plays a crucial role in inflammation-related carcinogenesis. We hypothesize that genetic variants in IL-17 are associated with gastric cancer (GCa) risk, and we genotyped five potentially functional single nucleotide polymorphisms (SNPs) (rs1974226 G > A, rs2275913 A > G, rs3819024 A > G, rs4711998 A > G, and rs8193036 C > T) of IL-17 in 1121 GCa patients and 1216 cancer-free controls in an eastern Chinese population. Logistic regression analysis was used to calculate odds ratios (OR) and 95% confidence intervals (CI). Meta-analysis and genotype-mRNA expression correlation were performed to further validate positive associations. We found that an increased GCa risk was independently associated with rs1974226 (adjusted OR = 2.60, 95% CI = 1.27-5.32 for AA vs. GG + GA) and rs2275913 (adjusted OR = 1.33, 95% CI = 1.03-1.72 for GA + AA vs. GG), while a decreased GCa risk was independently associated with rs3819024 (adjusted OR = 0.72, 95% CI = 0.54-0.96 for GG vs. AA + AG). Additional meta-analyses confirmed the observed risk association with rs2275913. We also found that two IL-17 haplotypes (G-G-G-A-C) and (A-G-G-A-C) (in the order of rs1974226, rs2275913, rs3819024, rs4711998 and rs8193036) were associated with a reduced GCa risk (adjusted OR = 0.64, 95% CI = 0.46-0.89 and adjusted OR = 0.38, 95% CI = 0.17-0.81, respectively). However, the expression Quantitative Trait Locus (eQTL) analysis for the genotype-phenotype correlation did not find mRNA expression changes associated with either the genotypes. In conclusions, genetic variants of IL-17 are likely to be associated with risk of GCa, and additional larger studies with functional validation are needed to explore the molecular mechanisms underlying the observed associations.

Claudin 1 Expression Levels Affect miRNA Dynamics in Human Basal-Like Breast Cancer Cells

Deemed a putative tumor suppressor in breast cancer, the tight junction protein claudin 1 has now been shown to be highly expressed in the basal-like molecular subtype. Moreover, recent in vitro studies show that claudin 1 can regulate breast cancer cell motility and proliferation. Herein, we investigated whether microRNA (miRNA) dysregulation is associated with alterations in the level of claudin 1. Using next-generation sequencing (NGS), we identified seven miRNAs (miR-9-5p, miR-9-3p, let-7c, miR-127-3p, miR-99a-5p, miR-129-5p, and miR-146a-5p) that were deregulated as a consequence of claudin 1 overexpression in the MDA-MB231 human breast cancer (HBC) cell line. Most of these miRNAs have been associated with tumor suppression in a variety of cancers, including breast cancer. Moreover, through gene expression profiling analysis, we identified epithelial-mesenchymal transition-related genes, including platelet-derived growth factor receptor-beta (PDGFRB) and cadherin 1 (CDH1, E cadherin), whose downregulation correlated with claudin 1 overexpression. Collectively, we show for the first time that in HBC, claudin 1 can alter the dynamics of a number of miRNAs involved in tumor progression. Our data suggest that the dysregulated expression of these miRNAs, in conjunction with the high claudin 1 levels, could serve as a useful biomarker that identifies a subset of tumors within the poorly characterized basal-like subtype of breast cancer. Further studies are warranted to determine the role of these miRNAs in facilitating the function of claudin 1 in breast cancer.

Association Between 3 IL-10 Gene Polymorphisms and Cardiovascular Disease Risk: Systematic Review With Meta-Analysis and Trial Sequential Analysis

Previous studies have yielded controversial results related to the contribution of interleukin 10 (IL-10) gene polymorphisms (IL-10 -592C/A, IL-10 -1082G/A, and IL-10 -819C/T) in the progression of cardiovascular disease (CVD). Thus, we performed a meta-analysis to summarize this situation.Eligible studies were retrieved by searching PubMed, Embase, Web of Science, and Cochrane Library with the last search up to July 7, 2015. Data were pooled by odds ratios (ORs) and their 95% confidence intervals (CIs). False-positive report probability (FPRP) analysis was conducted for all significant findings. Genotype-based mRNA expression analysis was also performed using data from 270 individuals with different ethnicities.Finally, 19 studies for IL-10 -592C/A polymorphism (7284 cases and 7469 controls), 21 studies for IL-10 -1082G/A polymorphism (8263 cases and 5765 controls), and 12 studies for IL-10 -819C/T polymorphism (4502 cases and 3190 controls) were included in the meta-analyses. With respect to IL-10 -819C/T polymorphism, statistically significant decreased CVD risk was found when all studies were pooled into the meta-analysis (T vs C: OR = 0.91, 95% CI = 0.84-0.98; TT + TC vs CC: OR = 0.90, 95% CI = 0.81-1.00). Subgroup analyses stratified by disease subtype suggested the -819C/T polymorphism was significantly associated with a decreased CAD risk (T vs C: OR = 0.90, 95% CI = 0.83-0.97; TT vs CC: OR = 0.81, 95% CI = 0.66-1.00; TT vs TC + CC: OR = 0.82, 95% CI = 0.69-0.98; TT + TC vs CC: OR = 0.89, 95% CI = 0.80-0.99), which was noteworthy finding as evaluated by FPRP. However, with regard to IL-10 -592C/A and IL-10 -1082G/A polymorphisms, no significant association with CVD risk was observed in the overall and subgroup analyses.In conventional meta-analyses, the results suggested that IL-10 -819C/T polymorphism was associated with decreased risk of CVD, especially CAD outcome, whereas IL-10 -592C/A and IL-10 -1082G/A polymorphisms might have no influence on the susceptibility of CVD. However, trial sequential analysis does not allow us to draw any solid conclusion for the association between IL-10 -592C/A or IL-10 -1082G/A polymorphism and CVD risk. Further large and well-designed studies are still needed.

Association between three interleukin-10 gene polymorphisms and coronary artery disease risk: a meta-analysis

BACKGROUND

Previous studies have investigated the associations between interleukin-10 (IL-10) gene polymorphisms (-592C/A, -819C/T and -1082G/A) and risk of coronary artery disease (CAD). However, the results were inconsistent. The aim of this study was to clarify the relationship between IL-10 polymorphisms and CAD risk by a meta-analysis approach.

METHODS

The PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI) and Wanfang databases were searched according to predefined criteria for all relevant studies published before June 1, 2015. Pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were computed to assess the association.

RESULTS

24 eligible studies were enrolled including 9736 CAD patients and 8606 controls. We observed a significant decreased risk of CAD for IL-10 -819C/T polymorphism (T allele vs. C allele:OR = 0.91, 95% CI = 0.84-0.99; TT vs. CT + CC:OR = 0.82, 95% CI = 0.69-0.98), especially in Asians (T allele vs. C allele:OR = 0.76, 95% CI = 0.60-0.96; TT vs. CC:OR = 0.51, 95% CI = 0.27-0.96; TT vs. CT + CC:OR = 0.62, 95% CI = 0.44-0.88). Moreover, we found IL-10 -1082G/A polymorphism might contribute to an increased CAD risk in Asians (AA vs. GG:OR = 1.89, 95% CI = 1.36-2.64; AA vs. AG + GG:OR = 1.39, 95% CI = 1.14-1.68) but not in other ethnic groups. However, no significant association between the IL-10 -592C/A polymorphism and CAD risk was observed.

CONCLUSIONS

Our results indicated that IL-10 -819C/T and IL-10 -1082G/A polymorphisms significantly and race-specifically correlate with CAD risk.

Interaction between common breast cancer susceptibility variants, genetic ancestry, and nongenetic risk factors in Hispanic women

BACKGROUND

Most genetic variants associated with breast cancer risk have been discovered in women of European ancestry, and only a few genome-wide association studies (GWAS) have been conducted in minority groups. This research disparity persists in post-GWAS gene-environment interaction analyses. We tested the interaction between hormonal and lifestyle risk factors for breast cancer, and ten GWAS-identified SNPs among 2,107 Hispanic women with breast cancer and 2,587 unaffected controls, to gain insight into a previously reported gene by ancestry interaction in this population.

METHODS

We estimated genetic ancestry with a set of 104 ancestry-informative markers selected to discriminate between Indigenous American and European ancestry. We used logistic regression models to evaluate main effects and interactions.

RESULTS

We found that the rs13387042-2q35(G/A) SNP was associated with breast cancer risk only among postmenopausal women who never used hormone therapy [per A allele OR: 0.94 (95% confidence intervals, 0.74-1.20), 1.20 (0.94-1.53), and 1.49 (1.28-1.75) for current, former, and never hormone therapy users, respectively, Pinteraction 0.002] and premenopausal women who breastfed >12 months [OR: 1.01 (0.72-1.42), 1.19 (0.98-1.45), and 1.69 (1.26-2.26) for never, <12 months, and >12 months breastfeeding, respectively, Pinteraction 0.014].

CONCLUSIONS

The correlation between genetic ancestry, hormone replacement therapy use, and breastfeeding behavior partially explained a previously reported interaction between a breast cancer risk variant and genetic ancestry in Hispanic women.

IMPACT

These results highlight the importance of understanding the interplay between genetic ancestry, genetics, and nongenetic risk factors and their contribution to breast cancer risk.

The prognostic value of IL10 and TNF alpha functional polymorphisms in premenopausal early-stage breast cancer patients

BACKGROUND

Interleukin-10 and tumor necrosis factor α play an important role in breast carcinogenesis. Genes, encoding those two cytokines, contain single nucleotide polymorphisms, which are associated with differential levels of gene transcription. This study analyzes single nucleotide polymorphisms in interleukin 10 and tumor necrosis factor α genes and their contribution to breast cancer phenotype, lymph node status and survival in a group of young Lithuanian women with early-stage breast cancer patients.

RESULTS

We genotyped 100 premenopausal Eastern European (Lithuanian) patients with stage I-II breast cancer, ≤ 50 years old at the time of diagnosis, for interleukin 10 -592A > C, -819C > T and -1082A > G and tumor necrosis factor α -308G > A single nucleotide polymorphisms in the gene promoter region. We used the polymerase chain reaction, namely a restriction fragment length polymorphism method, for a SNP analysis. All genotypes were in Hardy-Weinberg equilibrium and had the same distribution as the HapMap CEU population. Holders of IL10 -592A > C heterozygous IL10 -592 AC genotype had a higher probability of estrogen receptor positive breast cancer phenotype than homozygous variants (P = 0.017). Phased ACC haplotype of IL10 polymorphisms was associated with younger age of diagnosis (P = 0.017). Of all the tested single nucleotide polymorphisms, only TNFα -308G > A has revealed a prognostic capability for breast cancer survival. GA genotype carriers, compared to GG, showed a significant disadvantage in progression-free survival (P = 0.005, adjusted hazard ratio (HR) = 4.631, 95 % confidence interval (CI) = 1.587 - 13.512), metastasis-free survival (P = 0.010, HR = 4.708, 95 % CI = 1.445 - 15.345) and overall survival (P = 0.037, HR = 4.829, 95 % CI = 1.098 - 21.243).

CONCLUSIONS

According to our data, IL10 -1082A > G, -819 T > C, -592A > C polymorphisms and phased haplotypes have not revealed a prognostic value for breast cancer. On the contrary, the TNFα -308 polymorphism might modulate the risk and contribute to the identification of patients at a higher risk of breast cancer recurrence, metastasis and worse overall survival among young Lithuanian early-stage breast cancer patients.

Circulating interleukin-6 and cancer: A meta-analysis using Mendelian randomization

Interleukin-6 (IL-6) plays a contributory role in the progression and severity of many forms of cancer; it however remains unclear whether the relevance between circulating IL-6 and cancer is causal. We therefore meta-analyzed published articles in this regard using IL-6 gene -174G/C variant as an instrument. Seventy-eight and six articles were eligible for the association of -174G/C variant with cancer and circulating IL-6, respectively. Overall analyses failed to identify any significance between -174G/C and cancer risk. In Asians, carriers of the -174CC genotype had an 1.95-fold increased cancer risk compared with the -174GG genotype carriers (P = 0.009). By cancer type, significance was only attained for liver cancer with the -174C allele conferring a reduced risk under allelic (odds ratio or OR = 0.74; P = 0.001), homozygous genotypic (OR = 0.59; P = 0.029) and dominant (OR = 0.67; P = 0.004) models. Carriers of the -174CC genotype (weighted mean difference or WMD = −4.23 pg/mL; P < 0.001) and -174C allele (WMD = −3.43 pg/mL; P < 0.001) had circulating IL-6 reduced significantly compared with the non-carriers. In further Mendelian randomization analysis, a reduction of 1 pg/mL in circulating IL-6 was significantly associated with an 12% reduced risk of liver cancer. Long-term genetically-reduced circulating IL-6 might be causally associated with a lower risk of liver cancer.

Genetic variation in the JAK/STAT/SOCS signaling pathway influences breast cancer-specific mortality through interaction with cigarette smoking and use of aspirin/NSAIDs: the Breast Cancer Health Disparities Study

The Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway is involved in immune function and cell growth; genetic variation in this pathway could influence breast cancer risk. We examined 12 genes in the JAK/STAT/SOCS signaling pathway with breast cancer risk and mortality in an admixed population of Hispanic (2,111 cases, 2,597 controls) and non-Hispanic white (1,481 cases, 1,585 controls) women. Associations were assessed by Indigenous American (IA) ancestry. After adjustment for multiple comparisons, JAK1 (three of ten SNPs) and JAK2 (4 of 11 SNPs) interacted with body mass index (BMI) among pre-menopausal women, while STAT3 (four of five SNPs) interacted significantly with BMI among post-menopausal women to alter breast cancer risk. STAT6 rs3024979 and TYK2 rs280519 altered breast cancer-specific mortality among all women. Associations with breast cancer-specific mortality differed by IA ancestry; SOCS1 rs193779, STAT3 rs1026916, and STAT4 rs11685878 associations were limited to women with low IA ancestry, and associations with JAK1 rs2780890, rs2254002, and rs310245 and STAT1 rs11887698 were observed among women with high IA ancestry. JAK2 (5 of 11 SNPs), SOCS2 (one of three SNPs), and STAT4 (2 of 20 SNPs) interacted with cigarette smoking status to alter breast cancer-specific mortality. SOCS2 (one of three SNPs) and all STAT3, STAT5A, and STAT5B SNPs significantly interacted with use of aspirin/NSAIDs to alter breast cancer-specific mortality. Genetic variation in the JAK/STAT/SOCS pathway was associated with breast cancer-specific mortality. The proportion of SNPs within a gene that significantly interacted with lifestyle factors lends support for the observed associations.