Coffee consumption and CYP1A2*1F genotype modify age at breast cancer diagnosis and estrogen receptor status

The prevalence of ADSL (rs3788579) and CYP1A2 (rs17861162) polymorphisms in female breast cancer patients in North-West Iran

INTRODUCTION

Breast cancer is a prevalent and significant contributor to cancer-related mortality among women worldwide. Its increasing incidence, especially in regions like North-West Iran, necessitates a deeper understanding of genetic factors contributing to its development. Genetic alterations, particularly single nucleotide polymorphisms (SNPs), are implicated in breast cancer susceptibility, making investigation in this context crucial. This study explores the role of CYP1A2-rs17861162 and ADSL-rs3788579 SNPs in breast cancer risk among Iranian women.

METHODS

This study involved 200 female breast cancer patients and 200 healthy controls in North-West Iran. DNA was extracted from blood samples, and PCR-RFLP was used for genotyping the CYP1A2 and ADSL genes.

RESULTS

The CYP1A2-rs17861162 SNP exhibited a shift from the C allele to the G allele in breast cancer patients, resulting in a 21.7% decrease in CC genotype frequency and a 21.6% and 77.8% increase in CG and GG genotypes, respectively, compared to controls. In ADSL-rs3788579 SNP, breast cancer patients had a significantly higher prevalence of the T allele, with a 28.5% increase compared to controls. In healthy participants, CC was most common, while in the breast cancer group, TT was most common.

CONCLUSION

This study highlights significant genetic alterations in CYP1A2-rs17861162 and ADSL-rs3788579 SNPs among breast cancer patients in North-West Iran, suggesting their potential as diagnostic and prognostic biomarkers. Further research is warranted to elucidate the precise mechanisms underlying their contributions to breast cancer susceptibility in this population.

Coffee consumption and breast cancer risk: a narrative review in the general population and in different subtypes of breast cancer

PURPOSE

Most of the existing literature reports no association or a slight negative association between coffee consumption and the risk of developing breast cancer. However, the level of risk differs when considering various subgroups, such as menopausal status, hormonal status of the tumor or genetic mutations. The present review based on a literature search sets the point on the potential influence of a common daily drink, coffee, on the risk of developing breast cancer in the general population, in different subgroups of women and the consequences of drinking coffee after breast cancer has been diagnosed and treated.

RESULTS

This review confirms that in the general population, there is no association between coffee intake and breast cancer risk or a slight protective effect, even at high dosages. Coffee is inversely associated with breast cancer risk in postmenopausal women and in women carrying a BRCA1 mutation. Possible risk differences exist between slow and fast caffeine metabolizers and with weight. Coffee consumption after breast cancer diagnosis and surgery, associated with tamoxifen and/or radiotherapy, reduced the occurrence of early events. The effects of coffee intake are less clear in other subgroups, mainly premenopausal women, women carrying a BRCA2 mutation and tumors with variable hormonal status (positive or negative for ER/PR) and would need additional studies.

Interest of Fluvoxamine as an Add-On to Clozapine in Children With Severe Psychiatric Disorder According to CYP Polymorphisms: Experience From a Case Series

Despite its drastic efficacy in resistant psychiatric disorders, clozapine remains rarely used in youth due to its side effects. Clozapine plasma level is determined through its metabolism involving several isoforms of cytochromes 450 (CYP450) family. Isoform CYP1A2 appears as a limiting enzyme involved in the metabolism of clozapine, while isoforms 2C19, 2D6, 3A4, and 3A5 also contribute in a minor way. Clozapine efficacy is limited by a significant inter-patient variability in exposure according to CYP's polymorphisms. Clozapine plasma levels may be increased with CYP inhibitors such as fluvoxamine. This drug is a potent enzymatic inhibitor of CYP1A2 and, to a lesser extent, of CYP3A4 and CYP2D6. Hence, in case of CYP's polymorphisms in youth, the use of fluvoxamine as add-on to clozapine could help in reaching clinical and biological efficacy and allowing lower clozapine dosage and a better tolerance profile as it has already been described in adults. We report four pediatric cases with severe psychiatric disorders underlying our experience with CYP polymorphism explorations and the use of fluvoxamine as add-on to clozapine. Our four patients clinically improved after the introduction of fluvoxamine, enhancing clozapine metabolism and therefore the clozapine plasma level within therapeutic range. Despite the interesting results of fluvoxamine, we report a severe issue of tolerance for one patient, emphasizing the need for caution regarding possible drug interactions when fluvoxamine is considered. Hence, we propose a detailed step-by-step multidisciplinary protocol.

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.

SNP's in xenobiotic metabolism and male infertility

1. Glutathione S-transferases (GST) and cytochrome P450s (CYPs) are xenobiotic metabolizing enzymes participating in the protection of cell. The present study aimed to investigate the relationship between polymorphisms of glutathione S-transferase M1 (GSTM1) null, glutathione S-transferase T1 (GSTT1) null, glutathione S-transferase P1 (GSTP1) Ile105Val, cytochrome P450 1A2 (CYP1A2) 734 C→A, cytochrome P450 2D6 (CYP2D6) 1934 G→A and male infertility.2. A total of 306 azoospermic or oligozoospermic infertile men and 129 normozoospermic or fertile controls were enrolled in the study. Multiplex polymerase chain reaction (PCR) or PCR-restriction fragment length polymorphism methods were used for genotyping. There was a significant relationship between male infertility and CYP2D6 GG genotype (p < 0.001). CYP1A2 AA genotype was slightly higher in the infertile group (p = 0.056).3. There was no association between GSTT1 null polymorphisms and male infertility (p = 0.068), GSTM1 null (p = 0.843) and GSTP1 Ile105Val (p = 0.192) genes. GSTM1 null genotype frequency was higher in azoospermic men (p = 0.009). Men carrying CYP1A2 AA genotype had higher risk of infertility risk (OR = 3.14; %95 CI = 1.16-8.54) in the smoker group.4. Our results demonstrated that polymorphisms of CYP2D6 and CYP1A2 may play a role in idiopathic male infertility in our sample population.

The associations of genetic polymorphisms in CYP1A2 and CYP3A4 with clinical outcomes of breast cancer patients in northern China

Background

Cytochrome P450 (CYP) 1A2 and CYP3A4 may play a role in the differentiation of clinical outcomes among breast cancer women. This study aimed to analyze the association of genetic polymorphisms in the CYP1A2 and CYP3A4 genes with clinicopathological features, protein expression and prognosis of breast cancer in the northern Chinese population.

Results

Firstly, SNP rs11636419, rs17861162 and rs2470890 in the CYP1A2 were significantly associated with age and menstruation status. And SNP rs11636419 and rs17861162 were associated with the P53 status. Secondly, SNP rs2470890 was correlated with CYP1A2 protein expression under the co-dominant and dominant model (P = 0.017, P = 0.006, respectively). Thirdly, for SNP rs2470890, the Kaplan–Meier 5 year survival curves showed that patients carrying genotypes CT or TT had a worse OS compared with the genotype CC carriers under both codominant and dominant model (P < 0.001, P < 0.001, respectively).

Materials and Methods

Four single nucleotide polymorphisms (SNPs) were successfully genotyped in 459 breast cancer patients using the SNaPshot method. The associations of four polymorphisms with protein expression and clinicopathological characteristics were evaluated by Pearson's chi-square test. The Cox hazard regression analysis and Kaplan–Meier survival analysis were performed to evaluate the relationship between the SNPs and overall survival (OS) of breast cancer.

Conclusions

CYP1A2 rs2470890 was significantly associated with the prognosis of patients with breast cancer and could serve as an independent impact factor of prognosis of breast carcinoma.

Coffee Is Associated With Lower Breast Tumor Insulin-Like Growth Factor Receptor 1 Levels in Normal-Weight Patients and Improved Prognosis Following Tamoxifen or Radiotherapy Treatment

Coffee is associated with decreased breast cancer risk, but the impact of body mass index (BMI) in combination with coffee consumption on prognosis is unclear. The suppressive effect of coffee constituents on the insulin-like growth factor receptor 1 (IGF1R) levels in breast cancer cells may play a role. The aim was to investigate the prognostic impact of coffee consumption and possible associations with tumor-specific IGF1R protein expression and BMI in a population-based cohort in Sweden, comprising 1,014 primary breast cancer patients without pretreatment enrolled 2002-2012 and followed for up to 13 years. Patients with higher coffee consumption had lower tumor IGF1R levels (P = 0.025), but only among the normal-weight patients (P = 0.005). Coffee did not impact the recurrence-risk overall. However, tamoxifen-treated patients with ER⁺ tumors drinking ≥ 2 cups of coffee/day had lower recurrence-risk [adjusted HR (HR_adj) 0.57, 95% CI, 0.34-0.97] compared with patients with lower intake, although only among normal-weight patients (HR_adj 0.37, 95% CI: 0.17-0.78; P_interaction = 0.039). Similarly, coffee consumption ≥ 2 cups/day was associated with significantly lower recurrence-risk among the 640 radiotherapy-treated patients irrespective of BMI (HR_adj 0.59, 95% CI 0.36-0.98) and in the 296 normal-weight patients (HR_adj 0.36, 95% CI 0.17-0.76) but not in the 329 overweight or obese patients (HR_adj 0.88, 95% CI 0.42-1.82) although the interaction was not significant (P_interaction = 0.093). In conclusion, coffee consumption was negatively associated with tumor-specific IGF1R levels only among normal-weight patients. Though, IGF1R did not explain the association between coffee intake and improved prognosis among normal-weight tamoxifen- or radiotherapy-treated patients. Studies of IGF1R-targeting therapies may benefit from taking BMI and coffee consumption into account.

Expression of Genes for Methylxanthine Pathway-Associated Enzymes Accompanied by Sex Steroid Receptor Status Impacts Breast Carcinoma Progression

Consumption of methylxanthine alkaloids appears to induce activities by antagonizing adenosine receptors, implicated in breast cancer behavior in vitro. Our goal was to evaluate expression of genes for methylxanthine receptors and metabolizing enzymes to assess risk of breast carcinoma recurrence. Clinical outcomes, estrogen/progestin receptor results, and gene expression assays guided selection. RNA was isolated from laser capture microdissection-procured carcinoma cells for microarray using established protocols. Gene expression levels of eight methylxanthine receptors, eight metabolizing enzymes, and various phosphodiesterases were retrieved from microarray results. Univariable Cox regressions and Kaplan-Meier plots were determined for each gene with R software. Individually, lower expressions of PDE4A, CYP2A6, or CYP2E were related to decreased progression-free survival (PFS) and overall survival (OS). PDE1A over-expression predicted decreased PFS and OS. ADORA2B and RYR1 over-expressions predicted diminished OS. ER+ cancers exhibited lower ADORA1, ADORA2B, and RYR1 and elevated PDE4A, CYP2A6, and CYP2E expressions. Of PR+ carcinomas, diminished ADORA2B and RYR1 and elevated expressions of ADORA3, PDE4A, CYP2C8, and CYP2E were noted. Least absolute shrinkage and selection operator (LASSO) revealed that CYP2E, PDE1A, and PDE4A expressions collectively predicted PFS whereas ADORA1, CYP2E, PDE1A, PDE1B, and PDE4A expressions jointly predicted OS. Models were clinically significant when validated externally. LASSO also derived a six-gene model and five-gene model that predicted PFS of ER- or PR- carcinomas, respectively. Similarly, five-gene and four-gene models predicted OS in ER- or PR- carcinomas, respectively. Collectively, expression of genes involved in methylxanthine action and metabolism in single-cell types predicted clinical outcomes of breast carcinoma indicating promise for developing diagnostics and design of new therapeutics.

Body Mass Index Influences the Prognostic Impact of Combined Nuclear Insulin Receptor and Estrogen Receptor Expression in Primary Breast Cancer

The prognostic importance of tumor-specific nuclear insulin receptor (InsR) expression in breast cancer is unclear, while membrane and cytoplasmic localization of InsR is better characterized. The insulin signaling network is influenced by obesity and may interact with the estrogen receptor α (ERα) signaling. The purpose was to investigate the interplay between nuclear InsR, ER, body mass index (BMI), and prognosis. Tumor-specific expression of nuclear InsR was evaluated by immunohistochemistry in tissue microarrays from 900 patients with primary invasive breast cancer without preoperative treatment, included in a population-based cohort in Sweden (2002-2012) in relation to prognosis. Patients were followed for up to 11 years during which 107 recurrences were observed. Nuclear InsR⁺ expression was present in 214 patients (23.8%) and increased with longer time between surgery and staining (P < 0.001). There were significant effect modifications by ER status and BMI in relation to clinical outcomes. Nuclear InsR⁺ conferred higher recurrence-risk in patients with ER⁺ tumors, but lower risk in patients with ER^- tumors (P_interaction = 0.003). Normal-weight patients with nuclear InsR⁺ tumors had higher recurrence-risk, while overweight or obese patients had half the recurrence-risk compared to patients with nuclear InsR^- tumors (P_interaction = 0.007). Normal-weight patients with a nuclear InsR^-/ER⁺ tumor had the lowest risk for recurrence compared to all other nuclear InsR/ER combinations [HR_adj 0.50, 95% confidence interval (CI): 0.25-0.97], while overweight or obese patients with nuclear InsR^-/ER^- tumors had the worst prognosis (HR_adj 7.75, 95% CI: 2.04-29.48). Nuclear InsR was more prognostic than ER among chemotherapy-treated patients. In summary, nuclear InsR may have prognostic impact among normal-weight patients with ER⁺ tumors and in overweight or obese patients with ER^- tumors. Normal-weight patients with nuclear InsR^-/ER⁺ tumors may benefit from less treatment than normal-weight patients with other nuclear InsR/ER combinations. Overweight or obese patients with nuclear InsR^-/ER^- tumors may benefit from more tailored treatment or weight management.

High Estrogen Receptor β Expression Is Prognostic among Adjuvant Chemotherapy-Treated Patients-Results from a Population-Based Breast Cancer Cohort

PURPOSE

Isoform-specific tumor estrogen receptor β (ERβ) expression may hold prognostic information in breast cancer, especially among endocrine-treated breast cancer patients. The study's purpose was to evaluate ERβ isoform 1 (ERβ1) expression in relation to tumor characteristics, ESR2 genotypes, and prognosis in different treatment groups.

EXPERIMENTAL DESIGN

A population-based prospective cohort of 1,026 patients diagnosed with primary invasive breast cancer in Lund, Sweden, between October 2002 and June 2012 was followed until June 2014 (median 5 years). Associations between immunohistochemical ERβ1 expression, patient and tumor characteristics, as well as outcome within treatment groups were analyzed.

RESULTS

Tumor ERβ1 expression was available for 911 patients (89%) and was not associated with ESR2 genotypes. ERβ1 positivity, defined as >75% (ERβ1₇₅⁺, 72.7%), was positively associated with established favorable tumor characteristics. Overall, ERβ1₇₅⁺ was associated with lower risk of breast cancer events [HR_adj = 0.60; 95% confidence interval (CI), 0.41-0.89]. The magnitude of the association was larger in patients with ERα^- tumors (HR_adj = 0.30; 95% CI, 0.12-0.76), compared with ERα⁺ tumors (HR_adj = 0.66; 95% CI, 0.42-1.03). Among the 232 chemotherapy-treated patients, ERβ1₇₅⁺ tumors were associated with lower risk of breast cancer events compared with ERβ1₇₅^- tumors (HR_adj = 0.31; 95% CI, 0.15-0.64). Among the 671 chemonaïve patients, ERβ1₇₅ status was not associated with the outcome.

CONCLUSIONS

High ERβ1 expression was a favorable prognostic marker in this breast cancer cohort, especially in chemotherapy-treated patients, but not in endocrine therapy-treated patients. These results warrant confirmation, preferably via a biomarker study in a previously conducted randomized trial. Clin Cancer Res; 23(3); 766-77. ©2016 AACR.

Impacts of smoking on endocrine treatment response in a prospective breast cancer cohort

BACKGROUND

The association between smoking and breast cancer prognosis remains unclear. The purpose of this study was to investigate whether preoperative smoking was associated with prognosis in different treatment groups.

METHODS

This population-based cohort consisted of 1065 breast cancer patients without preoperative treatment included between 2002 and 2012 in Lund, Sweden. Smoking status was examined in relation to patient and tumour characteristics, and prognosis in different treatment groups.

RESULTS

At the preoperative visit, 21.0% smoked. Median follow-up time was 5.1 years. Overall, in the 1016 patients included in the survival analyses, there was no significant association between smoking and risk of breast cancer events (adjusted hazard ratio (adjHR): 1.45; 95% confidence interval (CI): 0.95-2.20). For the 309 aromatase inhibitor (AI)-treated patients ⩾50 years with oestrogen receptor-positive (ER+) tumours, smoking was associated with risk of breast cancer events (adjHR: 2.97; 95% CI: 1.44-6.13), distant metastasis (adjHR: 4.19; 95% CI: 1.81-9.72), and death (adjHR: 3.52; 95% CI: 1.59-7.81). Smoking was not associated with breast cancer events or distant metastasis in other treatment groups.

CONCLUSIONS

Preoperative smoking was only associated with an increased risk for breast cancer events and distant metastasis in AI-treated patients. If confirmed, smoking status should be taken into consideration when selecting an endocrine therapy.

CYP1A2--a novel genetic marker for early aromatase inhibitor response in the treatment of breast cancer patients

Background

Endocrine resistance is a major obstacle to optimal treatment effect in breast cancer. Some genetic markers have been proposed to predict response to aromatase inhibitors (AIs) but the data is insufficient. The aim of the study was to find new genetic treatment predictive markers of AIs.

Methods

The ongoing population-based BC-blood study in Lund, Sweden includes women with primary breast cancer. This paper is based on AI-treated patients with estrogen receptor positive tumors who underwent breast cancer surgery in 2002–2008. First, an exploratory analysis of 1931 SNPs in 227 genes involved in absorption, distribution, metabolism, and elimination of multiple medications, using DMET™ chips, was conducted in a subset of the cohort with last follow-up in December 31^st 2011 (13 cases, 11 controls). Second, selected SNPs from the first analysis were re-analyzed concerning risk for early breast cancer events in the extended cohort of 201 AI-treated with last follow-up in June 30^th 2014. Clinical data were obtained from medical records and population registries.

Results

Only CYP1A2 rs762551 C-allele was significantly associated with increased risk for early events in the 24 patients (P = 0.0007) and in the extended cohort, adjusted Hazard ratio (HR) 2.22 (95 % CI 1.03–4.80). However, the main prognostic impact was found within five years, adjusted HR 7.88 (95 % CI 2.13–29.19). The impact of the CYP1A2 rs762551 C-allele was modified by a functional polymorphism in the regulator gene AhR Arg554Lys (G > A). Compared to patients who were homozygous for the major allele in both genes (CYP1A2 A/A and AhR G/G), a 9-fold risk for early events was found in patients who had at least one minor allele in both genes, adjusted HR 8.95 (95 % CI 2.55–31.35), whereas patients with at least one minor allele in either but not both genes had a 3-fold risk for early events, adjusted HR 2.81 (95 % CI 1.07–7.33). The impact of CYP1A2 rs762551 C-allele was also modified by the CYP19A1 rs4646 C/C, adjusted HR 3.39 (95 % CI 1.60–7.16) for this combination. This association was strongest within the first five years, adjusted HR 10.42 (95 % CI 3.45–31.51).

Conclusion

CYP1A2 rs762551 was identified as a new potential predictive marker for early breast cancer events in AI-treated breast cancer patients. Moreover, combined genotypes of CYP1A2 rs762551 and CYP19A1 rs4646 or AhR Arg554Lys could further improve prediction of early AI-treatment response. If confirmed, these results may provide a way to more personalized medicine.

Breast Cancer Association with CYP1A2 Activity and Gene Polymorphisms--a Preliminary Case-control Study in Tunisia

The aim of the present study was to evaluate the relative contribution of CYP1A2 isoforms (-3860 G/A, -2467T/delT and -163C/A) in control subjects and breast cancer patients to the metabolism of caffeine in human liver. Restriction fragment length polymorphism analysis of PCR-amplified Fragments (PCR-RFLP) was used for the genotyping of CYP1A2 SNPs and HPLC allowed the phenotyping through the measurement of CYP1A2 activity using the 17X + 13X + 37X/137X urinary metabolite ratio (CMR) and plasma caffeine half life (T1/2). The CYP1A2 -3860A genotype was associated with a decreased risk of breast cancer. In contrast, distributions of the CYP1A2 -2467T/delT or -2467delT/delT and -163A/C or A/A genotypes among breast cancer patients and controls were similar. When the genotype and phenotype relationship was measured by comparing the mean CMR ratios and caffeine half life within the genotype groups between subjects and breast cancer patients, there were no significant differences except for -3860 A, most of them being homozygous for the -3860 G/G SNP and had a significant higher mean CMR ratio and half life than those with -3860 G/A (P=0.02). The results of this preliminary study show a significant association between CP1A2 -3860 G variant and CYP1A2 phenotype which must be confirmed by further large-size case-control studies.

Caffeine, coffee, and tea intake and urinary estrogens and estrogen metabolites in premenopausal women

BACKGROUND

Prior studies have found weak inverse associations between breast cancer and caffeine and coffee intake, possibly mediated through their effects on sex hormones.

METHODS

High-performance liquid chromatography/tandem mass spectrometry was used to quantify levels of 15 individual estrogens and estrogen metabolites (EM) among 587 premenopausal women in the Nurses' Health Study II with mid-luteal phase urine samples and caffeine, coffee, and/or tea intakes from self-reported food frequency questionnaires. Multivariate linear mixed models were used to estimate geometric means of individual EM, pathways, and ratios by intake categories, and P values for tests of linear trend.

RESULTS

Compared with women in the lowest quartile of caffeine consumption, those in the top quartile had higher urinary concentrations of 16α-hydroxyestrone (28% difference; Ptrend = 0.01) and 16-epiestriol (13% difference; Ptrend = 0.04), and a decreased parent estrogens/2-, 4-, 16-pathway ratio (Ptrend = 0.03). Coffee intake was associated with higher 2-catechols, including 2-hydroxyestradiol (57% difference, ≥4 cups/day vs. ≤6 cups/week; Ptrend = 0.001) and 2-hydroxyestrone (52% difference; Ptrend = 0.001), and several ratio measures. Decaffeinated coffee was not associated with 2-pathway metabolism, but women in the highest (vs. lowest) category of intake (≥2 cups/day vs. ≤1-3 cups/month) had significantly lower levels of two 16-pathway metabolites, estriol (25% difference; Ptrend = 0.01) and 17-epiestriol (48% difference; Ptrend = 0.0004). Tea intake was positively associated with 17-epiestriol (52% difference; Ptrend = 0.01).

CONCLUSION

Caffeine and coffee intake were both associated with profiles of estrogen metabolism in premenopausal women.

IMPACT

Consumption of caffeine and coffee may alter patterns of premenopausal estrogen metabolism.

Tumor-specific expression of HMG-CoA reductase in a population-based cohort of breast cancer patients

Background

The mevalonate pathway synthetizes cholesterol, steroid hormones, and non-steriod isoprenoids necessary for cell survival. 3-Hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) is the rate-limiting enzyme of the mevalonate pathway and the target for statin treatment. HMGCR expression in breast tumors has recently been proposed to hold prognostic and treatment-predictive information. This study aimed to investigate whether HMGCR expression in breast cancer patients was associated with patient and tumor characteristics and disease-free survival (DFS).

Methods

A population-based cohort of primary breast cancer patients in Lund, Sweden was assembled between October 2002 and June 2012 enrolling 1,116 patients. Tumor tissue microarrays were constructed and stained with a polyclonal HMGCR antibody (Cat. No HPA008338, Atlas Antibodies AB, Stockholm, Sweden, diluted 1:100) to assess the HMGCR expression in tumor tissue from 885 patients. HMGCR expression was analyzed in relation to patient- and tumor characteristics and disease-free survival (DFS) with last follow-up June 30^th 2014.

Results

Moderate/strong HMGCR expression was associated with less axillary lymph node involvement, lower histological grade, estrogen and progesterone receptor positivity, HER2 negativity, and older patient age at diagnosis compared to weak or no HMGCR expression. Patients were followed for up to 11 years. The median follow-up time was 5.0 years for the 739 patients who were alive and still at risk at the last follow-up. HMGCR expression was not associated with DFS.

Conclusion

In this study, HMGCR expression was associated with less aggressive tumor characteristics. However, no association between HMGCR expression and DFS was observed. Longer follow-up may be needed to evaluate HMGCR as prognostic or predictive marker in breast cancer.

IL6 genotype, tumour ER-status, and treatment predicted disease-free survival in a prospective breast cancer cohort

Background

In breast cancer, high levels of the inflammatory cytokine interleukin-6 (IL-6) have been associated with disease-free survival and treatment resistance. Increased serum levels of IL-6 have been correlated with increased levels of NF-κβ and aromatase expression in adipose tissue. Several IL6 single nucleotide polymorphisms have been associated with breast cancer prognosis, but the impact may differ depending on tumour oestrogen receptor (ER) status. This translational study investigated the association between IL6 genotypes, ER-status, and treatment on the risk of early events among breast cancer patients.

Methods

The study included 634 25- to 99-year-old primary breast cancer patients in Sweden from 2002–2008. Genotyped IL6 single nucleotide polymorphisms rs1800797, rs1800796, rs1800795, and rs2069849 were analysed separately and as diplotypes. Disease-free survival was assessed for 567 patients. Clinical data, patient-, and tumour-characteristics were obtained from questionnaires, patient charts, population registries, and pathology reports.

Results

The median follow-up time was 5.1 years. IL6 diplotype was not associated with early events for all 567 patients, but AGCC/AGCC diplotype-carriers with ER-negative tumours had an increased risk, (adjusted Hazard Ratio (HR) = 5.91, 95% CI: 1.28–27.42). Any C-carriers (rs1800795) with ER-negative tumours had a higher risk of early events than GG-carriers with ER-negative tumours, (adjusted HR = 3.76, 95% CI: 1.05–13.43), particularly after radiotherapy (adjusted HR = 7.17, 95% CI: 1.16–32.28). Irrespective of ER-status, chemotherapy-treated Any C-carriers had a higher risk of early events than GG-carriers (adjusted HR = 3.42, 95% CI: 1.01–11.54).

Conclusions

The main finding of the present study was that IL6 genotype was strongly associated with early events among patients with ER-negative tumours, particularly among radiotherapy-treated patients, and among chemotherapy-treated patients irrespective of ER-status. The high risk for early events observed in these subgroups of patients suggests that combined information on IL6 genotype, tumour ER-status, and breast cancer treatment may represent a tool for identifying patients who require more personalised treatment.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2407-14-759) contains supplementary material, which is available to authorized users.

Pre- and postoperative alcohol consumption in breast cancer patients: impact on early events

Purpose

To investigate the association between pre- and postoperative alcohol consumption and risk for early breast cancer events, since the association between alcohol consumption and prognosis in breast cancer patients is unclear.

Methods

Alcohol consumption was recorded for 934 primary breast cancer patients who underwent breast cancer surgery in Lund, Sweden, between 2002 and 2011 and were followed until December 31^st 2012. Clinical data were obtained from medical records and population registries. Pre- and postoperative alcohol consumption was analyzed in relation to risk for early events.

Results

Median follow-up time was 3.03 years and 100 breast cancer events, 65 distant metastases, and 76 deaths occurred. Compared to no consumption, any preoperative alcohol consumption was weakly associated with lower risk for early events, adjusted HR 0.69 (0.45-1.04), distant metastases, 0.60 (0.36-1.00) and death, 0.62 (0.38-1.01). In the 572 patients without axillary lymph node involvement, any alcohol consumption was not associated with risk for early events. However, in the 360 patients with axillary lymph node involvement, preoperative alcohol consumption was associated with lower risk for early events (adjusted HR 0.43 0.24-0.77; P_interaction = 0.01).

Conclusion

Pre- and postoperative alcohol consumption was weakly associated with lower risk for early breast cancer events. The data does not support recommending that all breast cancer patients abstain from low to moderate alcohol consumption.

Role of the CYP1A2 Gene Polymorphism on Early Ageing from Occupational Exposure

The ageing process is influenced by many internal and external factors. The toxic substances in the environment can cause genomic damages to cells, which increase the risk of early ageing. Furthermore, the cytochrome P450 1A2 (CYP1A2) gene polymorphism is a susceptibility factor and may enhance the risk of DNA damage in cells. The current study was carried out to show whether occupational exposure could cause genotoxicity in cells carrying the CYP1A2 gene polymorphism, thus enhancing the likelihood of early ageing. This study was conducted on mechanical workshop workers and a control group by collecting buccal cells from their mouths. Restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) was used to identify the CYP1A2 gene polymorphism in the cells. In addition, three extra methods including micronuclei (MN) test, comet assay and real-time PCR (RT-PCR) were applied to determine the effects of gene polymorphisms on DNA damage and ageing from occupational exposure. The results showed that DNA damage in the cells carrying the mutated genotype was higher than the wild genotype. In addition, the difference in MN frequency (p = 0.001) and relative telomere length (p = 0.002) between workers and controls was significant (p <0.05) in the mutated genotype. The findings indicated a possible protective effect of gene polymorphism against early ageing, which was characterized by lack of a significant influence of CYP1A2 gene polymorphism on genetic material in the subjects (p >0.05). It was concluded that the CYP1A2 gene could be a contributing factor to prevent early ageing from occupational exposure.

Impact of COX2 genotype, ER status and body constitution on risk of early events in different treatment groups of breast cancer patients

The COX2 rs5277 (306G>C) polymorphism has been associated with inflammation-associated cancers. In breast cancer, tumor COX-2 expression has been associated with increased estrogen levels in estrogen receptor (ER)-positive and activated Akt-pathway in ER-negative tumors. Our study investigated the impact of COX2 genotypes on early breast cancer events and treatment response in relation to tumor ER status and body constitution. In Sweden, between 2002 and 2008, 634 primary breast cancer patients, aged 25–99 years, were included. Disease-free survival was assessed for 570 rs5277-genotyped patients. Body measurements and questionnaires were obtained preoperatively. Clinical data, patient- and tumor-characteristics were obtained from questionnaires, patients' charts, population registries and pathology reports. Minor allele(C) frequency was 16.1%. Genotype was not linked to COX-2 tumor expression. Median follow-up was 5.1 years. G/G genotype was not associated with early events in patients with ER-positive tumors, adjusted HR 0.77 (0.46–1.29), but conferred an over 4-fold increased risk in patients with ER-negative tumors, adjusted HR 4.41 (1.21–16.02)(p_interaction = 0.015). Chemotherapy-treated G/G-carriers with a breast volume ≥850 ml had an increased risk of early events irrespective of ER status, adjusted HR 8.99 (1.14–70.89). Endocrine-treated C-allele carriers with ER-positive tumors and a breast volume ≥850 ml had increased risk of early events, adjusted HR 2.30 (1.12–4.75). COX2 genotype, body constitution and ER status had a combined effect on the risk of early events and treatment response. The high risk for early events in certain subgroups of patients suggests that COX2 genotype in combination with body measurements may identify patients in need of more personalized treatment.

No association found between CYP2D6 genotype and early breast cancer events in tamoxifen-treated patients

BACKGROUND

CYP2D6 is considered the key enzyme in tamoxifen metabolism. Several studies have investigated the relationship between the CYP2D6 genotype and tamoxifen treatment outcome, with discrepant results. CYP2D6 inhibitor use, aromatase inhibitor use, and chemotherapy may account for some of the discrepancies. We examined the association between CYP2D6 genotype and early breast cancer events in tamoxifen-treated breast cancer patients, in relation to CYP2D6 inhibitor use, aromatase inhibitor use, and chemotherapy.

MATERIAL AND METHODS

Pre- and postoperative questionnaires on lifestyle and concomitant medications were completed by 634 primary breast cancer patients between 2002 and 2008, among whom 333 patients had ER-positive tumors and received tamoxifen. CYP2D6*3, *4, *6, *10 and *41 were genotyped. Information on clinical data, breast cancer events, and tumor characteristics was obtained from patients' charts, population registries, the Regional Tumor Registry, and pathology reports.

RESULTS

Median follow-up was 4.9 years. Neither poor metabolizers (adjusted HR 0.50; 95% CI 0.07-3.82) nor intermediate metabolizers (adjusted HR 1.00; 95% CI 0.47-2.11) had an increased risk of early breast cancer events when compared with extensive metabolizers. CYP2D6 activity score (taking into account genotype and CYP2D6 inhibitor use) was not associated with early breast cancer events (LogRank, Ptrend = 0.44).

CONCLUSIONS

CYP2D6 genotype was not associated with tamoxifen treatment outcome, even when CYP2D6 inhibitor use, aromatase inhibitor use, or chemotherapy was taken into account. CYP2D6 genotype may be of minor importance for tamoxifen-treated patients in Scandinavia.

Excessive milk production during breast-feeding prior to breast cancer diagnosis is associated with increased risk for early events

Breast-feeding is a known protective factor against breast cancer. Breast-feeding duration is influenced by hormone levels, milk production, and lifestyle factors. The aims were to investigate how breast-feeding duration and milk production affected tumor characteristics and risk for early breast cancer events in primary breast cancer patients. Between 2002 and 2008, 634 breast cancer patients in Lund, Sweden, took part in an ongoing prospective cohort study. Data were extracted from questionnaires, pathology reports, and patients’ charts from 592 patients without preoperative treatment. Breast-feeding duration ≤12 months of the first child was associated with higher frequency of ER+/PgR+ tumors (P=0.02). Median follow-up time was 4.9 years. Higher risk for early events was observed for breast-feeding duration of first child >12 months (LogRank P=0.001), total breast-feeding duration >12 months (LogRank P=0.008), as well as ‘excessive milk production’ during breast-feeding of the first child (LogRank P=0.001). Patients with ‘almost no milk production’ had no events. In a multivariable model including both ‘excessive milk production’ and breast-feeding duration of the first child >12 months, both were associated with a two-fold risk for early events, adjusted HRs 2.33 (95% CI: 1.25-4.36) and 2.39 (0.97-5.85), respectively, while total breast-feeding duration was not. ‘Excessive milk production’ was associated with a two-fold risk of early distant metastases, adjusted HR 2.59 (1.13-5.94), but not duration. In conclusion, ‘excessive milk production’ during breast-feeding was associated with higher risk for early events independent of tumor characteristics, stressing the need to consider host factors in the evaluation of prognostic markers.

Considering CYP1A2 phenotype and genotype for optimizing the dose of olanzapine in the management of schizophrenia

INTRODUCTION

Schizophrenia, a mental disorder, is a debilitating condition which typically strikes young people in their early 20's. Antipsychotic medications are widely prescribed for the treatment of schizophrenia however a balancing act is necessary to provide the correct dose to each patient. It is suggested that a large number of patients discontinue antipsychotic pharmacotherapy because the treatments provided do not always reduce the positive symptoms of the disease, while many have adverse effects on the patients. This implies that neither the incorrect drug nor the optimal dosage for that patient is achieved.

AREAS COVERED

The current review investigates variability in response to olanzapine with a specific focus on the common intrinsic and extrinsic factors that influence both olanzapine and CYP1A2 activity. Furthermore, the authors discuss the utilization of phenotyping and genotyping of CYP1A2 and their potential utility in clinical practice for olanzapine dosing regimens. The authors also consider the potential of pharmacometrics compared to pharmacogenomics as a tool to personalize medicine.

EXPERT OPINION

Careful consideration must be given to the impact of a genetic variant on the disposition of a drug prior to implementing genetic 'tests' to determine response. CYP1A2 phenotypic assessment can yield important information regarding the disposition of olanzapine; however, it relies on the accuracy of the metric and the minimal impact of other metabolic pathways. The application of pharmacometrics provides an effective method to establish covariates that significantly influence olanzapine disposition which can incorporate phenotype and/or genotype.

Coffee consumption and risk of breast cancer: an up-to-date meta-analysis

Objectives

This updated meta-analysis was conducted to assess the association between coffee consumption and breast cancer risk.

Methods

We conducted a systematic search updated July 2012 to identify observational studies providing quantitative estimates for breast cancer risk in relation to coffee consumption. Pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated using a random-effects model, and generalized least square trend estimation was used to assess dose–response relationships.

Results

A total of 26 studies (16 cohort and 10 case–control studies) on coffee intake with 49497 breast cancer cases were included in the meta-analysis. The pooled RR showed a borderline significant influence of highest coffee consumption (RR = 0.96; 95% CI 0.93–1.00), low-to moderate coffee consumption (RR = 0.99; 95% CI 0.95–1.04), or an increment of 2 cups/day of coffee consumption (RR = 0.98; 95% CI 0.97–1.00) on the risk of breast cancer. In stratified analysis, a significant inverse association was observed in ER-negative subgroup. However, no significant association was noted in the others.

Conclusions

Our findings suggest that increased coffee intake is not associated with a significantly reduced risk of breast cancer, but we observe an inverse association in ER-negative subgroup analysis. More large studies are needed to determine subgroups to obtain more valuable data on coffee drinking and breast cancer risk.

Association between common CYP1A2 polymorphisms and theophylline metabolism in non-smoking healthy volunteers

This study was designed to investigate the impact of cytochrome P450 (CYP) 1A2 polymorphisms on theophylline metabolism in a non-smoking healthy male Chinese population. Four polymorphisms CYP1A2 1C (G-3860A), G-3113A, CYP1A2 1F (C-163A) and CYP1A2 1B (C-5347T) were screened in 238 unrelated male volunteers. Then, a single oral 200-mg dose of theophylline was administered to 37 volunteers, who were selected from 238 volunteers based on the CYP1A2 genotype. CYP1A2 activities were evaluated by plasma 1,7-dimethylxanthine/caffeine ratios (17X/137X) after administration of 100-mg caffeine. The plasma concentrations of theophylline, 17X and 137X were determined by high-performance liquid chromatography. The activity of CYP1A2 was lower in volunteers with the -3113 AA genotype compared with those with the -3113 AG genotype (0.35 ± 0.04 versus 0.48 ± 0.07, p = 0.016) or the -3113 GG genotype (0.35 ± 0.04 versus 0.58 ± 0.22, p = 0.037). CYP1A2 1F polymorphisms were associated with increased CYP1A2 activity in volunteers with -3860G/-3113G/5347C homozygosity (0.66 ± 0.24 versus 0.46 ± 0.05, p = 0.034). However, theophylline metabolism showed no difference among volunteers carrying different haplotype pairs. CYP1A2 genetic polymorphisms influenced CYP1A2 enzyme activity as measured by caffeine, but CYP1A2 gene polymorphisms appeared to have limited influence on theophylline metabolism in our study.

Role of CYP1A2 polymorphisms in breast cancer risk in women

Cytochrome P4501A2 (CYP1A2) is a key enzyme in the etiology of breast cancer (BC). It is involved in breast carcinogen activation [aromatic (AAs) and heterocyclic amines (HAs), polycyclic aromatic hydrocarbons (PAHs)], in the production of beneficial oestrogen [2-hydroxyestrone (2-OHE1)] and in converting arachidonic acid (AAc) to epoxyeicosatrienoic acids (EETs), which have anti-inflammatory properties. Within a hospital-based case-control study, the effect of functional CYP1A2 variants [-3860G/A (rs2069514), -2467T/delT (rs3569413), -163C/A (rs762551)] and their interactions with environmental factors in BC risk was investigated. The study population included 125 BC cases and 43 non-cancer controls. Genotyping was performed in RT-PCR using Taqman assays. The gene-environment interaction was appraised using a case-only study design. We found that the -3860A variant, independently from environmental factors, as well as by interacting with fried foods (p=0.025) and indoor exposure to pollutants (p=0.050), reduced the risk of BC (p=0.025), whereas its interaction with coffee (p=0.045) increased the BC risk. This is the first study indicating that the -3860A variant, by decreasing CYP1A2 activity, modifies BC risk by interacting with environmental factors, thereby supporting the hypothesis that reduced CYP1A2 activity contributes to BC risk in different ways, for example, it may be protective by reducing the activation of pro-carcinogens such as AAs, HAs and PAHs, but would increase risk by reducing the beneficial formation of 2-OHE1 and EETs.

Clinical profiles predict early nonadherence to adjuvant endocrine treatment in a prospective breast cancer cohort

Nonadherence to adjuvant endocrine breast cancer treatment adversely affects disease-free and overall survival. Clinical predictors of nonadherence may allow for specific interventions to reduce nonadherence and improve survival. The aim was to investigate whether clinical characteristics predict nonadherence. Clinical characteristics and information on adherence were obtained from 417 patients with breast cancer in a population-based prospective cohort from southern Sweden using patient charts, pathology reports, and questionnaires filled out at the 1- and 2-year follow-up visits. At the 1- and 2-year follow-up visits, 36 (8.6%) and 33 (9.7%) patients were nonadherent, respectively. Thirteen of the nonadherent patients declined treatment and were never prescribed endocrine treatment. A body mass index (BMI) < 25 kg/m(2), preoperative current smoking, and drinking alcohol less often than twice a month predicted nonadherence at the 1-year [relative risk (RR), 5.24; 95% confidence interval (CI), 2.75-9.97] and the 2-year visits (RR, 4.07; 95% CI, 2.11-7.84) in patients with at least two of these clinical characteristics. When low histologic grade (I) was added to the model, having at least two of these four clinical characteristics predicted nonadherence at the 1-year (RR, 4.94; 95% CI, 2.46-10.00) and the 2-year visits (RR, 4.74; 95% CI, 2.28-9.87), the two profiles had a sensitivity ranging from 60.6% to 72.7%, whereas the specificity ranged from 68.0% to 78.4%. Nonadherence at the 1-year visit was associated with an increased risk for early breast cancer events (HR, 2.97; 95% CI, 1.08-8.15), adjusted for age and tumor characteristics. In conclusion, two clinical profiles predicted early nonadherence and may allow for targeted interventions to increase adherence if validated in an independent cohort.

Androgen receptor genotypes predict response to endocrine treatment in breast cancer patients

BACKGROUND

The androgen receptor (AR) is frequently expressed in breast cancers. The AR genotype may affect disease-free survival and response to endocrine therapy.

METHODS

In all, 634 women undergoing breast cancer surgery between 2002 and 2008 were followed until 30 June 2010. Six haplotype-tagging single-nucleotide polymorphisms in the AR, and the resulting AR diplotypes, were examined in relation to breast cancer patient characteristics, tumour characteristics, disease-free survival, and response to endocrine treatment.

RESULTS

Five common AR diplotypes were found. Seventeen rare variants were combined into a composite group. The resulting six AR diplotype groups were clustered into two subgroups, groups A (n=128) and B (n=499), with three diplotypes in each. Patients in group B had larger total breast volume (P=0.024), higher body mass index (BMI) (P=0.050), more axillary lymph node involvement (P(trend)=0.020), and higher histological grade (P(trend)=0.031). There were 59 breast cancer events in the 569 patients with invasive cancers and no preoperative treatment. Patients in group B also had shorter disease-free survival (P=0.037) than patients in group A. Among patients in group B with oestrogen receptor α positive tumours, tamoxifen (TAM) treatment was associated with longer disease-free survival (P=0.008), while treatment with aromatase inhibitors (AIs) was not (P=0.94). Response to endocrine treatment could not be predicted based on BMI, suggesting that the effect of AR diplotypes went beyond that of a higher BMI.

CONCLUSION

A marker for a group of patients who responded to TAM, but not to AIs, was identified. If this finding is confirmed, AR genotyping may provide useful information for selection of endocrine treatment of breast cancer patients.

N-acetyltransferase 2, exposure to aromatic and heterocyclic amines, and receptor-defined breast cancer

The role of N-acetyltransferase 2 (NAT2) polymorphism in breast cancer is still unclear. We explored the associations between potential sources of exposure to aromatic and heterocyclic amines (AHA), acetylation status and receptor-defined breast cancer in 1020 incident cases and 1047 population controls of the German GENICA study. Acetylation status was assessed as slow or fast. Therefore, NAT2 haplotypes were estimated using genotype information from six NAT2 polymorphisms. Most probable haplotypes served as alleles for the deduction of NAT2 acetylation status. The risks of developing estrogen receptor alpha (ER) and progesterone receptor (PR)-positive or negative tumors were estimated for tobacco smoking, consumption of red meat, grilled food, coffee, and tea, as well as expert-rated occupational exposure to AHA with logistic regression conditional on age and adjusted for potential confounders. Joint effects of these factors and NAT2 acetylation status were investigated. Frequent consumption of grilled food and coffee showed higher risks in slow acetylators for receptor-negative tumors [grilled food: ER-: odds ratio (OR) 2.57, 95% confidence interval (CI) 1.07-6.14 for regular vs. rare; coffee: ER-: OR 2.55, 95% CI 1.22-5.33 for >or=4 vs. 0 cups/day]. We observed slightly higher risks for never smokers that are fast acetylators for receptor-positive tumors compared with slow acetylators (ER-: OR 1.32, 95% CI 1.00-1.73). Our results support differing risk patterns for receptor-defined breast cancer. However, the modifying role of NAT2 for receptor-defined breast cancer is difficult to interpret in the light of complex mixtures of exposure to AHA.

Lack of association of CYP1A2-164 A/C polymorphism with breast cancer susceptibility: a meta-analysis involving 17,600 subjects

Published data on the association between cytochrome P-450 1A2 (CYP1A2)-164 A/C polymorphism and breast cancer risk are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. Medline, PubMed, Embase, and Web of Science were searched. Crude ORs with 95% CIs were used to assess the strength of association between CYP1A2-164 A/C polymorphism and breast cancer risk. The pooled ORs were performed for co-dominant model (AC versus AA, CC versus AA), dominant model (CC + AC versus AA), and recessive model (CC versus AA + AC), respectively. A total of 9 studies including 7,580 cases and 10,020 controls were involved in this meta-analysis. Overall, no significantly elevated breast cancer risk was found in all genetic models when all studies were pooled into the meta-analysis (AC versus AA: OR = 1.02, 95% CI = 0.92-1.13; CC versus AA: OR = 1.17, 95% CI = 0.83-1.64; dominant model: OR = 1.07, 95% CI = 0.93-1.23; and recessive model: OR = 1.13, 95% CI = 0.82-1.55). In the subgroup analysis by ethnicity or source of controls, there was still no significant association detected in all genetic models. In conclusion, upto date, there is still not enough evidence to indicate the association of CYP1A2-164 A/C polymorphism and breast cancer development.

Coffee intake and CYP1A2*1F genotype predict breast volume in young women: implications for breast cancer

As breast volume may be associated with heart cancer risk, we studied the relationship between breast volume, CYP1A2*1F and coffee intake. Among healthy premenopausal non-hormone users, 3+ cups per day was associated with lower volume only in C-allele carriers (P_interaction=0.02), which is consistent with reports that coffee protects only C-allele carriers against breast cancer.