Interaction between ADH1C Arg272Gln and alcohol intake in relation to breast cancer risk suggests that ethanol is the causal factor in alcohol related breast cancer

Effects of ethanol or ethylene glycol exposure on PPARγ and aromatase expression in adipose tissue

The estrogen-synthesizing enzyme aromatase is expressed in adipose tissue where it controls the local concentration of estrogen. It has been suggested that the organic solvents ethanol and ethylene glycol can induce estrogen synthesis by inhibiting PPARγ activity. Since elevated estrogen synthesis in adipose tissue is a risk factor for breast cancer development, it is of interest to further characterize the mechanisms regulating aromatase expression. Here, we explored the mechanisms by which ethanol and ethylene glycol modulate aromatase mRNA expression and the ultimate conversion of androgens into estrogens. NMR spectroscopy revealed that ethanol and ethylene glycol influence the active state of PPARγ. An inhibitory effect on PPARγ was confirmed by adipogenesis assays and PPARγ target gene expression analysis in adipocytes. However, only ethanol increased aromatase mRNA in differentiated human adipocytes. In contrast, ethylene glycol downregulated aromatase in a PPARγ-independent manner. An animal study using female Wistar rats was conducted to assess the acute effects of ethanol and ethylene glycol on aromatase expression in adipose tissue within a physiological context. No changes in aromatase or PPARγ target gene (Adipoq and Fabp4) levels were observed in adipose tissue or ovary in response to the chemical exposures, suggesting an absence of acute PPARγ-mediated effects in these organs. The results suggest that ethanol and ethylene glycol are weak PPARγ antagonists in mouse and human adipocytes as well as in cell-free NMR spectroscopy. Both compounds seem to affect adipocyte aromatase expression in vitro, where ethanol increased aromatase expression PPARγ-dependently and ethylene glycol decreased aromatase expression independently of PPARγ. No acute effects on aromatase expression or PPARγ activity were observed in adipose tissue or ovary in rats in this study design.

Integrative bioinformatics approaches to establish potential prognostic immune-related genes signature and drugs in the non-small cell lung cancer microenvironment

Introduction: Research has revealed that the tumor microenvironment (TME) is associated with the progression of malignancy. The combination of meaningful prognostic biomarkers related to the TME is expected to be a reliable direction for improving the diagnosis and treatment of non-small cell lung cancer (NSCLC).

Method and Result: Therefore, to better understand the connection between the TME and survival outcomes of NSCLC, we used the “DESeq2” R package to mine the differentially expressed genes (DEGs) of two groups of NSCLC samples according to the optimal cutoff value of the immune score through the ESTIMATE algorithm. A total of 978 up-DEGs and 828 down-DEGs were eventually identified. A fifteen-gene prognostic signature was established via LASSO and Cox regression analysis and further divided the patients into two risk sets. The survival outcome of high-risk patients was significantly worse than that of low-risk patients in both the TCGA and two external validation sets (p-value < 0.05). The gene signature showed high predictive accuracy in TCGA (1-year area under the time-dependent ROC curve (AUC) = 0.722, 2-year AUC = 0.708, 3-year AUC = 0.686). The nomogram comprised of the risk score and related clinicopathological information was constructed, and calibration plots and ROC curves were applied, KEGG and GSEA analyses showed that the epithelial-mesenchymal transition (EMT) pathway, E2F target pathway and immune-associated pathway were mainly involved in the high-risk group. Further somatic mutation and immune analyses were conducted to compare the differences between the two groups. Drug sensitivity provides a potential treatment basis for clinical treatment. Finally, EREG and ADH1C were selected as the key prognostic genes of the two overlapping results from PPI and multiple Cox analyses. They were verified by comparing the mRNA expression in cell lines and protein expression in the HPA database, and clinical validation further confirmed the effectiveness of key genes.

Conclusion: In conclusion, we obtained an immune-related fifteen-gene prognostic signature and potential mechanism and sensitive drugs underling the prognosis model, which may provide accurate prognosis prediction and available strategies for NSCLC.

Association of Self-Reported Depression Symptoms with Physical Activity Levels in Czechia

Worldwide, depressive disorder is one of the leading determinants of disability-adjusted life years. Although there are benefits associated with a higher physical activity (PA) level, there is a lack of information related to this relationship, especially in countries such as Czechia, where modern approaches to mental health care only recently emerged. The present study aimed to evaluate the association between the level of depression and different PA levels following the World Health Organization (WHO) PA guidelines and according to specific symptoms that indicate depression. Multivariable-adjusted Poisson regression models were used to calculate the prevalence rate (PR) in a sample of 2123 participants (45.3% men, median 48 years). Compared to subjects with insufficient PA, moderate and high PA levels were inversely associated with continuous depression scores (PR = 0.85; 95% CI: 0.75-0.97; and PR = 0.80; 95% CI: 0.70-0.92). Depressed mood and worthlessness were the symptoms associated with moderate and high PA. Tiredness, change in appetite, and concentration problems were related to high PA. The results suggest that reaching the minimum PA target according to the guidelines seems to be effective, and this could stimulate adherence. However, more specific improvements in symptomatology will require a subsequent gradual increase in PA levels.

ADH1C Facilitates Cisplatin Resistance of Lung Adenocarcinoma Cells

Lung adenocarcinoma (LUAD) is a common form of lung cancer. Although cisplatin chemotherapy is an effective treatment option, some patients with LUAD can develop drug resistance. Modulated ADH1C expression has been reported in various cancer types. However, the mechanism by which ADH1C potentially influences progression and cisplatin resistance of LUAD remains poorly understood. In this study, we aimed to explore the role of ADH1C with respect to cisplatin resistance and to uncover the clinical significance of methionine adenosyltransferase (MAT1A). Compared with cisplatin-sensitive A549 cells, ADH1C was highly enriched in cisplatin-resistant A549/cis-dichlorodiammineplatinum II (DDP) cells. Inhibition of ADH1C expression in the latter suppressed cell proliferation and decreased their resistance to cisplatin. Furthermore, the proliferative capacity under cisplatin stimulation was reduced. Downregulation of ADH1C expression inhibited the expression of proliferating cell nuclear antigen and excision repair cross-complementing 1 (ERCC1). Knockdown of ADH1C resulted in arrested cell cycle (in G2/M phase). The proliferative capacity and cisplatin sensitivity induced by ADH1C upregulation in A549 cells were reversed upon knockdown of ADH1C. Bioinformatic analyses revealed ADH1C to be mainly enriched in cell cycle, RNA transport, biosynthesis of amino acids, and platinum drug resistance pathways. Meanwhile, the gene MAT1A with considerable positive association with ADH1C was identified. Furthermore, expression of MAT1A was upregulated in LUAD tissues relative to the paired adjacent normal specimens. Human Protein Atlas, The university of alabama at birmingham cancer data analysis portal (UALCAN), and Kaplan-Meier Plotter analysis indicated that upregulated MAT1A expression is correlated with poor prognosis of LUAD. Our results indicate that the ADH1C/MAT1A axis possibly increases cisplatin resistance in LUAD cells. The experiment was repeated three times and approved by the Medical Ethical Committee of the First Affiliated Hospital of Wenzhou Medical University (approval No.YS2018001).

Genome-wide analysis reveals alcohol dehydrogenase 1C and secreted phosphoprotein 1 for prognostic biomarkers in lung adenocarcinoma

To seek out novel promising biomarkers for predicting lung adenocarcinoma (LUAD) prognosis, we conducted this study. First, 279 upregulated and 37 downregulated differentially expressed genes were obtained from LUAD and para-carcinoma tissues by the Affymetrix GeneChip Human Transcriptome Array. Then, we randomly classified samples of LUAD data set GSE31210 as training and testing sets in a 1:1 ratio. Alcohol dehydrogenase 1C (ADH1C) and secreted phosphoprotein 1 (SPP1) were finally identified correlating with the LUAD survival through least absolute shrinkage and selection operator penalized Cox proportion hazards regression model, and applied to build a 2-gene signature related to prognosis in training set. Univariate and multivariable survival analyses suggested that overall survival (OS) and relapse-free survival (RFS) in the 2-gene signature low-risk group were better than the high-risk group. Kaplan-Meier curves proved that elevated ADH1C expression and reduced SPP1 expression were related to better OS and RFS. Besides, the SPP1 expressed higher in LUAD than para-carcinoma tissues using quantitative reverse transcription polymerase chain reaction assay. Finally, the association between the two genes and clinicopathological parameters in 80 LUAD were analyzed, it is suggested that SPP1 was relevant to epidermal growth factor receptor mutation. These findings indicated that ADH1C and SPP1 might be novel promising biomarkers for predicting LUAD prognosis.

Alcohol drinking, ADH1B and ADH1C genotypes and the risk of postmenopausal breast cancer by hormone receptor status: the Netherlands Cohort Study on diet and cancer

Alcohol consumption has consistently been shown to increase breast cancer (BC) risk. This association may be modified by single nucleotide polymorphisms (SNPs) in alcohol dehydrogenase (ADH) isoenzymes ADH1B and ADH1C. The Netherlands Cohort Study comprises 62 573 women, aged 55-69 years at baseline (1986). Follow-up for postmenopausal BC for 20.3 years was available. Genotyping of six tag SNPs in ADH1B and ADH1C was performed on DNA from toenails. A case-cohort approach was used for analysis (complete data available for nsubcohort = 1301; ncases = 1630). Cox regression models for postmenopausal BC were applied to determine marginal effects of alcohol intake and SNPs using a dominant genetic model, as well as multiplicative interaction of the two. Results were also obtained for subtypes by estrogen receptor (ER) and progesterone receptor (PR) status. Multiple testing was adjusted for by applying the false discovery rate (FDR). Alcohol intake (categorical) increased the risk of postmenopausal BC (Ptrend = 0.031). Trends for ER and PR subgroups followed a similar pattern. Continuous modeling of alcohol resulted in a hazard rate ratio (HR) for overall postmenopausal BC of 1.09 (95% confidence interval: 1.01-1.19) per 10 g/day of alcohol. SNPs were not associated with BC risk. No effect modification of the alcohol-BC association by SNP genotype was seen after FDR correction in overall BC and ER/PR subgroups. In conclusion, alcohol consumption was shown to increase the risk of postmenopausal BC. This association was not significantly modified by common SNPs in ADH1B and ADH1C, neither in overall BC nor in hormone receptor-defined subtypes.

Alcohol consumption and its interaction with adiposity-associated genetic variants in relation to subsequent changes in waist circumference and body weight

Background

Studies have suggested a link between alcohol intake and adiposity. However, results from longitudinal studies have been inconsistent, and a possible interaction with genetic predisposition to adiposity measures has often not been taken into account.

Objective

To examine the association between alcohol intake recorded at baseline and subsequent annual changes in body weight (∆BW), waist circumference (ΔWC) and WC adjusted for BMI (ΔWC_BMI), and to test for interaction with genetic predisposition scores based on single nucleotide polymorphisms (SNPs) associated with various forms of adiposity.

Method

This study included a total of 7028 adult men and women from MONICA, the Diet, Cancer and Health cohort (DCH), and the Inter99 studies. We combined 50 adiposity-associated SNPs into four scores indicating genetic predisposition to BMI, WC, WHR_BMI and all three traits combined. Linear regression was used to examine the association of alcohol intake (drinks of 12 g (g) alcohol/day) with ΔBW, ΔWC, and ΔWC_BMI, and to examine possible interactions with SNP-scores. Results from the analyses of the individual cohorts were combined in meta-analyses.

Results

Each additional drink/day was associated with a ΔBW/year of −18.0 g (95% confidence interval (CI): −33.4, −2.6, P = 0.02) and a ΔWC of −0.3 mm/year (−0.5, −0.0, P = 0.03). In analyses of women only, alcohol intake was associated with a higher ΔWC_BMI of 0.5 mm/year (0.2, 0.9, P = 0.002) per drink/day. Overall, we found no statistically significant interactions between the four SNP-scores and alcohol intake in relation to changes in adiposity measures. However in analyses of women separately, we found interaction between the complete score of all 50 SNPs and alcohol intake in relation to ΔBW (P for interaction = 0.03). No significant interaction was observed among the men.

Conclusion

Alcohol intake was associated with a decrease in BW and WC among men and women, and an increase in WC_BMI among women only_. We found no strong indication that these associations depend on a genetic predisposition to adiposity.

Trial registration

Registry: ClinicalTrials.gov Trial number: CT00289237, Registered: 19 September 2005 retrospectively registered.

Electronic supplementary material

The online version of this article (10.1186/s12937-017-0274-1) contains supplementary material, which is available to authorized users.

Association between single nucleotide polymorphisms in the antioxidant genes CAT, GR and SOD1, erythrocyte enzyme activities, dietary and life style factors and breast cancer risk in a Danish, prospective cohort study

Exposure to estrogens and alcohol consumption - the two only well-established risk factors for breast cancer - are capable of causing oxidative stress, which has been linked to progression of breast cancer. Here, five functional polymorphisms in the antioxidant genes SOD1, CAT and GSR were investigated in 703 breast cancer case-control pairs in the Danish, prospective “Diet, Cancer and Health” cohort together with gene-environment interactions between the polymorphisms, enzyme activities and intake of fruits and vegetables, alcohol and smoking in relation to breast cancer risk. Our results showed that genetically determined variations in the antioxidant enzyme activities of SOD1, CAT and GSR were not associated with risk of breast cancer per se. However, intake of alcohol, fruit and vegetables, and smoking status interacted with some of the polymorphisms in relation to breast cancer risk. Four polymorphisms were strongly associated with enzyme activity, but there was no interaction between any of the studied environmental factors and the polymorphisms in relation to enzyme activity. Additionally, single measurement of enzyme activity at entry to the cohort was not associated with risk of breast cancer. Our results therefore suggest that the antioxidant enzyme activities studied here are not major determinants of breast cancer risk.

Annotating the Function of the Human Genome with Gene Ontology and Disease Ontology

Increasing evidences indicated that function annotation of human genome in molecular level and phenotype level is very important for systematic analysis of genes. In this study, we presented a framework named Gene2Function to annotate Gene Reference into Functions (GeneRIFs), in which each functional description of GeneRIFs could be annotated by a text mining tool Open Biomedical Annotator (OBA), and each Entrez gene could be mapped to Human Genome Organisation Gene Nomenclature Committee (HGNC) gene symbol. After annotating all the records about human genes of GeneRIFs, 288,869 associations between 13,148 mRNAs and 7,182 terms, 9,496 associations between 948 microRNAs and 533 terms, and 901 associations between 139 long noncoding RNAs (lncRNAs) and 297 terms were obtained as a comprehensive annotation resource of human genome. High consistency of term frequency of individual gene (Pearson correlation = 0.6401, p = 2.2e - 16) and gene frequency of individual term (Pearson correlation = 0.1298, p = 3.686e - 14) in GeneRIFs and GOA shows our annotation resource is very reliable.

Alcohol-related breast cancer in postmenopausal women - effect of CYP19A1, PPARG and PPARGC1A polymorphisms on female sex-hormone levels and interaction with alcohol consumption and NSAID usage in a nested case-control study and a randomised controlled trial

Background

Alcohol consumption is associated with increased risk of breast cancer (BC), and the underlying mechanism is thought to be sex-hormone driven. In vitro and observational studies suggest a mechanism involving peroxisome proliferator-activated receptor gamma (PPARγ) in a complex with peroxisome proliferator-activated receptor gamma coactivator 1-α (PGC-1α) and interaction with aromatase (encoded by CYP19A1). Use of non-steroidal anti-inflammatory drugs (NSAID) may also affect circulating sex-hormone levels by modifying PPARγ activity.

Methods

In the present study we assessed whether genetic variation in CYP19A1 is associated with risk of BC in a case-control study group nested within the Danish “Diet, Cancer and Health” cohort (n_cases = 687 and n_controls = 687) and searched for gene-gene interaction between CYP19A1 and PPARGC1A, and CYP19A1 and PPARG, and gene-alcohol and gene-NSAID interactions. Association between the CYP19A1 polymorphisms and hormone levels was also examined among 339 non-HRT users. Incidence rate ratios were calculated based on Cox’ proportional hazards model. Furthermore, we performed a pilot randomised controlled trial to determine the effect of the PPARG Pro¹²Ala polymorphism and the PPARγ stimulator Ibuprofen on sex-hormone levels following alcohol intake in postmenopausal women (n = 25) using linear regression.

Results

Genetic variations in CYP19A1 were associated with hormone levels (estrone: P_rs11070844 = 0.009, estrone sulphate: P_rs11070844 = 0.01, P_rs749292 = 0.004, P_rs1062033 = 0.007 and P_rs10519297 = 0.03, and sex hormone-binding globulin (SHBG): P_rs3751591 = 0.03) and interacted with alcohol intake in relation to hormone levels (estrone sulphate: P_{interaction/rs2008691} = 0.02 and P_{interaction/rs1062033=} 0.03, and SHBG: P_{interaction/rs11070844} = 0.03). CYP19A1/rs3751591 was both associated with SHBG levels (P = 0.03) and with risk of BC (Incidence Rate Ratio = 2.12; 95 % Confidence Interval: 1.02–4.43) such that homozygous variant allele carriers had increased levels of serum SHBG and were at increased risk of BC. Acute intake of alcohol decreased blood estrone (P = <0.0001), estrone sulphate (P = <0.0001), and SHBG (P = 0.009) levels, whereas Ibuprofen intake and PPARG Pro¹²Ala genotype had no effect on hormone levels.

Conclusions

Our results suggest that genetically determined variation in CYP19A1 is associated with differences in sex hormone levels. However, the genetically determined differences in sex hormone levels were not convincingly associated with BC risk. The results therefore indicate that the genetically determined variation in CYP19A1 contributes little to BC risk and to alcohol-mediated BC risk.

Trial registration

NCT02463383, June 3, 2015.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2317-y) contains supplementary material, which is available to authorized users.

In vitro screening of inhibition of PPAR-γ activity as a first step in identification of potential breast carcinogens

Alcohol consumption and increased estrogen levels are major risk factors for breast cancer, and peroxisome proliferator-activated receptor γ (PPAR-γ) plays an important role in alcohol-induced breast cancer. PPAR-γ activity is inhibited by ethanol, leading to increased aromatase activity and estrogen biosynthesis ultimately leading to breast cancer. If other organic solvents inhibit PPAR-γ activity, they should also lead to increased oestrogen biosynthesis and thus be potential breast carcinogens. Ten commonly used hydrophilic organic solvents were first tested in a cell-based screening assay for inhibitory effects on PPAR-γ transactivation. The chemicals shown to inhibit PPAR-γ were tested with vectors encoding PPAR-γ with deleted AB domains and only the ligand-binding domain to rule out unspecific toxicity. Next, the effects on biosynthesis of estradiol, testosterone and oestrone sulphate were measured in the H295R steroidogenesis assay after incubation with the chemicals. Ethylene glycol, ethyl acetate, and dimethyl sulphoxide inhibited PPAR-γ transactivation in a dose-dependent manner. The inhibitory effect on PPAR-γ was specific for PPAR-γ since the AB domain of PPAR-γ was required for the inhibitory effect. In the second step, ethylene glycol significantly increased production of oestradiol by 19% ( p < 0.05) and ethyl acetate inhibited production of testosterone ( p < 0.05). We here show that screening of 10 commonly used organic solvents for the ability to inhibit PPAR-γ transactivation followed by a well-established steroidogenesis assay for production of sex hormones in exposed H295 R cells may provide a screening tool for potential breast carcinogens. This initial screening thus identified ethylene glycol and possibly ethyl acetate as potential breast carcinogens.

Alcohol and breast cancer: reconciling epidemiological and molecular data

Breast cancer is the most diagnosed cancer in women worldwide. Epidemiological studies have suggested a possible causative role of alcohol consumption as a risk factor for breast cancer. However, such conclusions should be interpreted with considerable caution for several reasons. While epidemiological studies can help identify the roots of health problems and disease incidence in a community, they are by necessity associative and cannot determine cause and effect relationships. In addition, all these studies rely on self-reporting to determine the amount and type of alcoholic beverage consumed, which introduces recall bias. This is documented in a recent study which stated that the apparent increased risk of cancer among light-moderate drinkers may be "substantially due to underreporting of intake." Another meta-analysis about alcohol and breast cancer declared "the modest size of the association and variation in results across studies leave the causal role of alcohol in question." Furthermore, breast cancer develops over decades; thus, correlations between alcohol consumption and breast cancer cannot be determined in epidemiological studies with windows of alcohol exposure that captures current or recent alcohol intake, after clinical diagnosis. Numerous risk factors are involved in breast carcinogenesis; some are genetic and beyond the control of a woman; others are influenced by lifestyle factors. Breast cancer is a heterogeneous and polygenic disease which is further influenced by epigenetic mechanisms that affect the transciptomes, proteomes and metabolomes, and ultimately breast cancer evolution. Environmental factors add another layer of complexity by their interactions with the susceptibility genes for breast cancer and metabolic diseases. The current state-of-knowledge about alcohol and breast cancer association is ambiguous and confusing to both a woman and her physician. Confronting the huge global breast cancer issue should be addressed by sound science. It is advised that women with or without a high risk for breast cancer should avoid overconsumption of alcohol and should consult with their physician about risk factors involved in breast cancer. Since studies associating moderate alcohol consumption and breast cancer are contradictory, a woman and her physician should weigh the risks and benefits of moderate alcohol consumption.

Association between polymorphisms in glutathione peroxidase and selenoprotein P genes, glutathione peroxidase activity, HRT use and breast cancer risk

Breast cancer (BC) is one of the most common cancers in women. Evidence suggests that genetic variation in antioxidant enzymes could influence BC risk, but to date the relationship between selenoproteins and BC risk remains unclear. In this report, a study population including 975 Danish cases and 975 controls matched for age and hormone replacement therapy (HRT) use was genotyped for five functional single nucleotide polymorphisms (SNPs) in SEPP1, GPX1, GPX4 and the antioxidant enzyme SOD2 genes. The influence of genetic polymorphisms on breast cancer risk was assessed using conditional logistic regression. Additionally pre-diagnosis erythrocyte GPx (eGPx) activity was measured in a sub-group of the population. A 60% reduction in risk of developing overall BC and ductal BC was observed in women who were homozygous Thr carriers for SEPP1 rs3877899. Additionally, Leu carriers for GPX1 Pro198Leu polymorphism (rs1050450) were at ∼2 fold increased risk of developing a non-ductal BC. Pre-diagnosis eGPx activity was found to depend on genotype for rs713041 (GPX4), rs3877899 (SEPP1), and rs1050450 (GPX1) and on HRT use. Moreover, depending on genotype and HRT use, eGPx activity was significantly lower in women who developed BC later in life compared with controls. Furthermore, GPx1 protein levels increased in human breast adenocarcinoma MCF7 cells exposed to β-estradiol and sodium selenite.In conclusion, our data provide evidence that SNPs in SEPP1 and GPX1 modulate risk of BC and that eGPx activity is modified by SNPs in SEPP1, GPX4 and GPX1 and by estrogens. Our data thus suggest a role of selenoproteins in BC development.

Alcohol Intake and Breast Cancer Risk: Weighing the Overall Evidence

Moderate alcohol consumption has been linked to an approximate 30-50% increased risk in breast cancer. Case-control and cohort studies have consistently observed this modest increase. We highlight recent evidence from molecular epidemiologic studies and studies of intermediate markers like mammographic density that provide additional evidence that this association is real and not solely explained by factors/correlates of the exposure and outcome present in non-randomized studies. We also review evidence from studies of higher risk women including BRCA1 and BRCA2 mutation carriers. Given the incidence of heart disease is higher than breast cancer and modest alcohol consumption is associated with reduced risk of heart disease, we examine the latest evidence to evaluate if alcohol reduction should be targeted to women at high risk for breast cancer. We also review the most recent evidence on the effect of alcohol use on tumor recurrence and survival for those diagnosed with breast cancer.

The alcohol dehydrogenase 1C(rs698) genotype and breast cancer: a meta-analysis

Published data regarding the association between alcohol dehydrogenase (ADH) 1C genotypes and breast cancer risk show conflicting results. The authors performed this meta-analysis on 1969 patients and 2244 controls from 4 (including 7 study populations) related case-control studies to estimate the association between ADH1C(rs698) genotyping information and breast cancer risk. According to the 6 eligible populations, the odds ratios (ORs) and 95% confidence intervals (CIs) for breast cancer risk for ADH1C (1-2) versus ADH1C (2-2) , ADH1C (1-1) versus ADH1C (2-2) genotype, and ADH1C (1) versus ADH1C (2) were 1.16 (0.95-1.42), 1.17 (0.95-1.44), and 1.05 (0.96-1.16), respectively. The OR (95% CI) for ADH1C (1-1) + ADH1C (1-2) versus ADH1C (2-2) from the 7 study populations was 1.14 (0.96-1.36). Meanwhile, genotypes of ADH1C (1-1) + ADH1C (1-2) increased the risk of breast cancer in drinkers (OR = 1.35; 95% CI = 1.03-1.76). This meta-analysis suggested that the ADH1C (1) allele might modestly influence the effect of alcohol on breast cancer but is not an independent risk factor for breast cancer. However, more restricted prospective studies are needed.

Alcohol intake

Alcohol consumption and its association with health or illness states are of great interest from the nutritional genomics point of view. This interest is centered not only on investigating the genetic variants that can modulate the effects of alcoholic beverages on different intermediate and final disease phenotypes (mainly cardiovascular diseases and cancer), but also on finding out how the genome influences the amount of alcohol consumed and consumption habits. This chapter reviews the latest findings on alcohol consumption trends, the methodological limitations in the analysis of alcohol consumption, and the main genes and polymorphisms related to alcohol intake, including the inconsistent results from genome-wide association studies (GWASs). It also reviews the effects of alcohol consumption on cardiovascular diseases and cancer and the studies analyzing the interactions between different genetic polymorphisms and alcohol in phenotypes related to these diseases, discussing the studies' advantages and limitations as well as future research perspectives.

PPARgamma-PGC-1alpha activity is determinant of alcohol related breast cancer

Alcohol is a risk factor for postmenopausal breast cancer. One of several proposed mechanisms is that alcohol-related breast cancer is caused by increased sex hormone levels. PPARγ inhibits aromatase transcription in breast adipocytes. We reproduced previously found allele-specific effects of the wildtype Pro-allele of PPARG Pro(12)Ala in alcohol related breast cancer. In transiently transfected cells, transcriptional activation by PPARγ and the PPARγ-PGC-1α complex was inhibited by ethanol. PPARγ 12Ala-mediated transcription activation was not enhanced by PGC-1α, resulting in allele-specific transcription activation by the PPARγ 12Pro-PGC-1α complex. Our results suggest that PPARγ and PGC-1α activity is an important determinant of alcohol related breast cancer.