Chronic Inflammation and Breast Pathology: A Theoretical Model

Oxidative Stress in Breast Cancer: A Biochemical Map of Reactive Oxygen Species Production

This review systematizes information about the metabolic features of breast cancer directly related to oxidative stress. It has been shown those redox changes occur at all levels and affect many regulatory systems in the human body. The features of the biochemical processes occurring in breast cancer are described, ranging from nonspecific, at first glance, and strictly biochemical to hormone-induced reactions, genetic and epigenetic regulation, which allows for a broader and deeper understanding of the principles of oncogenesis, as well as maintaining the viability of cancer cells in the mammary gland. Specific pathways of the activation of oxidative stress have been studied as a response to the overproduction of stress hormones and estrogens, and specific ways to reduce its negative impact have been described. The diversity of participants that trigger redox reactions from different sides is considered more fully: glycolytic activity in breast cancer, and the nature of consumption of amino acids and metals. The role of metals in oxidative stress is discussed in detail. They can act as both co-factors and direct participants in oxidative stress, since they are either a trigger mechanism for lipid peroxidation or capable of activating signaling pathways that affect tumorigenesis. Special attention has been paid to the genetic and epigenetic regulation of breast tumors. A complex cascade of mechanisms of epigenetic regulation is explained, which made it possible to reconsider the existing opinion about the triggers and pathways for launching the oncological process, the survival of cancer cells and their ability to localize.

Dietary Inflammatory Index and risk of breast cancer: evidence from a prospective cohort of 67,879 women followed for 20 years in France

BACKGROUND

Inflammation is implicated in breast cancer development, and diet is one of the modifiable risk factors involved in the regulation of chronic inflammation. Previous studies on the association between breast cancer risk and Dietary Inflammatory Indexes (DII) derived from food frequency questionnaires and data on inflammatory potential of dietary components have reported inconsistent results.

OBJECTIVE

To investigate the association between the DII and the risk of breast cancer using data from a large population-based cohort study.

DESIGN

A total of 67,879 women from the E3N cohort were followed from 1993 to 2014. A total of 5686 breast cancer cases were diagnosed during the follow-up. The food frequency questionnaire administered at baseline in 1993 was used to calculate an adapted DII. Cox proportional hazard models using age as the time scale were used to estimate hazard ratios (HR) and 95% confidence intervals (CI). Spline regression was used to determine any dose-response relationship. We also evaluated effect modification by menopausal status, body mass index, smoking status and alcohol consumption.

RESULTS

The median DII score of the study population was slightly pro-inflammatory (DII = + 0.39); ranged from - 4.68 in the lowest quintile to + 4.29 in the highest quintile. The HR increased linearly with the DII (HR per 1SD = 1.04 [95% CI: 1.01, 1.07]), and reached 1.13 [95% CI: 1.04, 1.23] in the 5th quintile group as compared to the first. A positive linear dose-response relationship was also observed when modeling DII with spline functions. Slightly higher HRs were observed in non-smokers (HR _{for 1-SD increase} 1.06 [95% CI: 1.02, 1.10]; p trend = 0.001) and in low-alcohol consumers (≤ 1 glass/day) (HR _{for 1-SD increase} 1.05 [95% CI: 1.01, 1.08]; p trend = 0.002).

CONCLUSION

Our results suggest a positive association between DII and breast cancer risk. Consequently, the promotion of anti-inflammatory diet may contribute to breast cancer prevention.

Circulating inflammatory biomarkers, adipokines and breast cancer risk-a case-control study nested within the EPIC cohort

BACKGROUND

Inflammation has been hypothesized to play a role in the development and progression of breast cancer and might differently impact breast cancer risk among pre and postmenopausal women. We performed a nested case-control study to examine whether pre-diagnostic circulating concentrations of adiponectin, leptin, c-reactive protein (CRP), tumour necrosis factor-α, interferon-γ and 6 interleukins were associated with breast cancer risk, overall and by menopausal status.

METHODS

Pre-diagnostic levels of inflammatory biomarkers were measured in plasma from 1558 case-control pairs from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. We used conditional logistic regression to estimate the odds ratios (ORs) of breast cancer at blood collection, per one standard deviation increase in biomarker concentration.

RESULTS

Cases were diagnosed at a mean age of 61.4 years on average 8.6 years after blood collection. No statistically significant association was observed between inflammatory markers and breast cancer risk overall. In premenopausal women, borderline significant inverse associations were observed for leptin, leptin-to-adiponectin ratio and CRP [OR= 0.89 (0.77-1.03), OR= 0.88 (0.76-1.01) and OR= 0.87 (0.75-1.01), respectively] while positive associations were observed among postmenopausal women [OR= 1.16 (1.05-1.29), OR= 1.11 (1.01-1.23), OR= 1.10 (0.99-1.22), respectively]. Adjustment for BMI strengthened the estimates in premenopausal women [leptin: OR = 0.83 (0.68-1.00), leptin-to-adiponectin ratio: OR = 0.80 (0.66-0.97), CRP: OR = 0.85 (0.72-1.00)] but attenuated the estimates in postmenopausal women [leptin: OR = 1.09 (0.96-1.24), leptin-to-adiponectin ratio: OR = 1.02 (0.89-1.16), CRP: OR = 1.04 (0.92-1.16)].

CONCLUSIONS

Associations between CRP, leptin and leptin-to-adiponectin ratio with breast cancer risk may represent the dual effect of obesity by menopausal status although this deserves further investigation.

Therapeutic Target Analysis and Molecular Mechanism of Melatonin - Treated Leptin Resistance Induced Obesity: A Systematic Study of Network Pharmacology

BACKGROUND

Obesity is a medical problem with an increased risk for other metabolic disorders like diabetes, heart problem, arthritis, etc. Leptin is an adipose tissue-derived hormone responsible for food intake, energy expenditure, etc., and leptin resistance is one of the significant causes of obesity. Excess leptin secretion by poor diet habits and impaired hypothalamic leptin signaling leads to LR. Melatonin a sleep hormone; also possess antioxidant and anti-inflammatory properties. The melatonin can attenuate the complications of obesity by regulating its targets towards LR induced obesity.

AIM

The aim of this study includes molecular pathway and network analysis by using a systems pharmacology approach to identify a potential therapeutic mechanism of melatonin on leptin resistance-induced obesity.

METHODS

The bioinformatic methods are used to find therapeutic targets of melatonin in the treatment of leptin resistance-induced obesity. It includes target gene identification using public databases, Gene ontology, and KEGG pathway enrichment by 'ClusterProfiler' using the R language, network analysis by Cytoscape, and molecular Docking by Autodock.

RESULTS

We obtained the common top 33 potential therapeutic targets of melatonin and LR-induced obesity from the total melatonin targets 254 and common LR obesity targets 212 using the data screening method. They are involved in biological processes related to sleep and obesity, including the cellular response to external stimulus, chemical stress, and autophagy. From a total of 180 enriched pathways, we took the top ten pathways for further analysis, including lipid and atherosclerosis, endocrine, and AGE-RAGE signaling pathway in diabetic complications. The top 10 pathways interacted with the common 33 genes and created two functional modules. Using Cytoscape network analysis, the top ten hub genes (TP53, AKT1, MAPK3, PTGS2, TNF, IL6, MAPK1, ERBB2, IL1B, MTOR) were identified by the MCC algorithm of the CytoHubba plugin. From a wide range of pathway classes, melatonin can reduce LR-induced obesity risks by regulating the major six classes. It includes signal transduction, endocrine system, endocrine and metabolic disease, environmental adaptation, drug resistance antineoplastic, and cardiovascular disease.

CONCLUSION

The pharmacological mechanism of action in this study shows the ten therapeutic targets of melatonin in LR-induced obesity.

A case-control study in France showing that a pro-inflammatory diet is associated with a higher risk of breast cancer

Dietary regimens promoting inflammatory conditions have been implicated in breast cancer development, but studies on the association between pro-inflammatory diet and breast cancer risk have reported inconsistent results. We investigated the association between the inflammatory potential of diet and breast cancer risk in a case-control study in France including 872 breast cancer cases and 966 population controls. All women completed a food frequency questionnaire that was used to compute a Dietary Inflammatory Index (DII) based on the inflammatory weight of 33 dietary components. The DII ranged from a median of - 3.22 in the lowest quartile (anti-inflammatory) to + 2.96 in the highest quartile (pro-inflammatory). The odds ratio contrasting quartile 4 to quartile 1 was 1.31 (95% CI 1.00, 1.73; p-trend = 0.02). Slightly higher odds ratios were observed in post-menopausal women, particularly those with body mass index > 25 kg/m2 (odds ratio 1.62; 95% CI 0.92, 2.83; p-trend = 0.02), and among ever smokers (odds ratio 1.71; 95% CI 1.11, 2.65; p-trend 0.01). The analyses by breast cancer subtype showed that the DII was associated with breast tumors that expressed either the estrogen (ER) or progesterone (PR) hormone receptors or the Human Epidermal Growth Factor Receptor-2 (HER2), but no association was seen for the triple negative breast tumor subtype. Our results add further evidence that a pro-inflammatory diet is associated with breast cancer risk with possible effect variation according to tumor subtype.

Effects of Psychological Inoculation Versus Health Education on Physical Activity: Two Randomized Controlled Studies

BACKGROUND

Effects of health education (HE) on physical activity (PA) are limited. Also, HE fails to address people's personal barriers and social pressures. In contrast, "psychological inoculation" (PI) targets both topics. This research examined the effects of PI versus HE on PA-related barriers and on self-reported PA in 2 studies.

METHODS

Randomized controlled trials were employed. Study 1 (N = 20) took place in Britain, while study 2 (N = 40) in Belgium, with nonphysically active participants. PI exposed people to challenging sentences reflecting barriers concerning PA, which they had to refute. In study 1, PA barriers and self-reported PA levels were assessed before and a week after interventions. In study 2, the degree of refuting challenging sentences was estimated and the level of PA was assessed before and 2 months after interventions.

RESULTS

In study 1, in the PI condition alone, PA barriers significantly decreased and self-reported PA increased. Change in barriers correlated with posttreatment PA. In study 2, PA increased only in the PI group. Level of rejecting challenging sentences predicted PA later. Most group differences remained when controlling for baseline measures.

CONCLUSIONS

PI is more effective than HE for increasing PA, and reducing its barriers is essential for this.

Association between expression of inflammatory markers in normal breast tissue and mammographic density among premenopausal and postmenopausal women

OBJECTIVE

Inflammatory markers may be associated with breast cancer risk. We assessed the association between expression levels of proinflammatory (interleukin 6, tumor necrosis factor-α, C-reactive protein, cyclooxygenase 2, leptin, serum amyloid A1, interleukin 8, and signal transducer and activator of transcription 3) and anti-inflammatory markers (transforming growth factor-β, interleukin 10, and lactoferrin) in normal breast tissue with mammographic density, a strong breast cancer risk indicator, among 163 breast cancer patients.

METHODS

The expression of inflammatory markers was visually evaluated on immunohistochemistry stained slides. The percent mammographic density (PMD) was estimated by a computer-assisted method in the contralateral cancer-free breast. We used generalized linear models to estimate means of PMD by median expression levels of the inflammatory markers while adjusting for age and waist circumference.

RESULTS

Higher expression levels (above median) of the proinflammatory marker interleukin 6 were associated with higher PMD among all women (24.1% vs 18.5%, P = 0.007). Similarly, higher expression levels (above median) of the proinflammatory markers (interleukin 6, tumor necrosis factor-α, C-reactive protein, and interleukin 8) were associated with higher PMD among premenopausal women (absolute difference in the PMD of 8.8% [P = 0.006], 7.7% [P = 0.022], 6.7% [P = 0.037], and 16.5% [P = 0.032], respectively). Higher expression levels (above median) of the anti-inflammatory marker transforming growth factor-β were associated with lower PMD among all (18.8% vs 24.3%, P = 0.005) and postmenopausal women (14.5% vs 20.7%, P = 0.013).

CONCLUSIONS

Our results provide support for the hypothesized role of inflammatory markers in breast carcinogenesis through their effects on mammographic density. Inflammatory markers could be targeted in future breast cancer prevention interventions.

Association between physical activity and the expression of mediators of inflammation in normal breast tissue among premenopausal and postmenopausal women

Physical activity is associated with decreased breast cancer risk. The underlying biological mechanisms could include the reduction of the local inflammation in the breast tissue. We conducted a cross-sectional study to assess the association between the physical activity and the protein expression levels of eleven mediators of inflammation in normal breast tissue of 164 women having breast cancer. Information on total physical activity (household, occupational and recreational) performed during a one-year period was collected using a questionnaire. Normal breast tissue was obtained from mastectomy blocks distant from the tumor. The expression of the mediators of inflammation in normal breast tissue was visually evaluated by immunohistochemistry. Multivariate linear regression analyses were used to assess the prevalence ratios (PR) and 95% confidence intervals (CI) for higher protein expression levels of the mediators of inflammation in normal breast tissue across quartiles of physical activity. Higher total physical activity was associated with lower expression levels of the pro-inflammatory mediator TNF-α in normal breast epithelial tissue among all (PR=0.64, 95% CI=0.44-0.93 for the fourth quartile; P_trend=0.013), premenopausal (PR=0.61, 95% CI=0.41-0.91 for the fourth quartile; P_trend=0.014) and postmenopausal women (PR=0.45, 95% CI=0.21-0.96 for the fourth quartile; P_trend=0.022). Conversely, higher total physical activity was associated with higher expression levels of the anti-inflammatory mediator IL-10 in normal breast epithelial tissue among all (PR=1.66, 95% CI=0.97-2.85 for the fourth quartile; P_trend=0.071) and postmenopausal women (PR=4.69, 95% CI=1.26-17.43 for the fourth quartile; P_trend=0.010). Our findings suggest a beneficial effect of physical activity on the local inflammatory profile in the breast tissue.

Association between local inflammation and breast tissue age-related lobular involution among premenopausal and postmenopausal breast cancer patients

Increased levels of pro-inflammatory markers and decreased levels of anti-inflammatory markers in the breast tissue can result in local inflammation. We aimed to investigate whether local inflammation in the breast tissue is associated with age-related lobular involution, a process inversely related to breast cancer risk. Levels of eleven pro- and anti-inflammatory markers were assessed by immunohistochemistry in normal breast tissue obtained from 164 pre- and postmenopausal breast cancer patients. Involution status of the breast (degree of lobular involution and the predominant lobule type) was microscopically assessed in normal breast tissue on hematoxylin-eosin stained mastectomy slides. Multivariate generalized linear models were used to assess the associations. In age-adjusted analyses, higher levels of pro-inflammatory markers IL-6, TNF-α, CRP, COX-2, leptin, SAA1 and IL-8; and anti-inflammatory marker IL-10, were inversely associated with the prevalence of complete lobular involution (all P≤0.04). Higher levels of the pro-inflammatory marker COX-2 were also associated with lower prevalence of predominant type 1/no type 3 lobules in the breast, an indicator of complete involution, in age-adjusted analysis (P = 0.017). Higher tissue levels of inflammatory markers, mainly the pro-inflammatory ones, are associated with less involuted breasts and may consequently be associated with an increased risk of developing breast cancer.

The IL-6 Gene Promoter SNP and Plasma IL-6 in Response to Diet Intervention

We recently reported that interleukin-6 (IL-6), an inflammatory marker associated with breast pathology and the development of breast cancer, decreases with diet intervention and weight loss in both insulin-sensitive and insulin-resistant obese women. Here, we tested whether an individual’s genotype at an IL6 SNP, rs1800795, which has previously been associated with circulating IL-6 levels, contributes to changes in IL-6 levels or modifies the effect of diet composition on IL-6 in these women. We genotyped rs1800795 in overweight/obese women (N = 242) who were randomly assigned to a lower fat (20% energy), higher carbohydrate (65% energy) diet; a lower carbohydrate (45% energy), higher fat (35% energy) diet; or a walnut-rich (18% energy), higher fat (35% energy), lower carbohydrate (45% energy) diet in a 1-year weight loss intervention study of obesity-related biomarkers for breast cancer incidence and mortality. Plasma IL-6 levels were measured at baseline, 6 and 12 months. At baseline, individuals with a CC genotype had significantly lower IL-6 levels than individuals with either a GC or GG genotype (p < 0.03; 2.72 pg/mL vs. 2.04 pg/mL), but this result was not significant when body mass index (BMI) was accounted for; the CC genotype group had lower BMI (p = 0.03; 32.5 kg/m² vs. 33.6 kg/m²). We did not observe a 2-way interaction of time*rs1800795 genotype or diet*rs1800795 genotype. Our findings provide evidence that rs1800795 is associated with IL-6 levels, but do not support a differential interaction effect of rs1800795 and diet composition or time on changes in circulating IL-6 levels. Diet intervention and weight loss are an important strategy for reducing plasma IL-6, a risk factor of breast cancer in women, regardless of their rs1800795 genotype.

Increased TNF α, IL-6 and ErbB2 mRNA expression in peripheral blood leukocytes from breast cancer patients

Obesity has been associated with increased incidence and mortality of breast cancer. The precise relation between obesity and breast cancer is yet to be determined, with few studies linking them with altered serum levels adipokines and inflammatory cytokines. The relevance of the expression of genes encoding for adipokines and inflammatory cytokines in the peripheral blood and their contribution to obesity and breast cancer has not been fully investigated. We aim to identify potential transcriptional biomarkers in blood samples that may assist to underpin the link between obesity and breast cancer. Therefore, have investigated whether or not the expression levels, of selected genes [tumor necrosis factor-α (TNFα), interleukin 6 (IL-6), adiponectin, leptin, C-reactive protein (CRP), parathyroid hormone (PTH), tumor protein 53 (TP53) and erythroblastic leukemia viral oncogene 2 (ErbB2)] were altered in blood samples of lean, overweight/obese and breast cancer subjects. Blood samples were obtained from 37 lean, 19 overweight/obese and 12 breast cancer patients. Real-time polymerase chain reaction assays were performed to detect TNFα, IL-6, adiponectin, leptin, CRP, PTH, TP53 and ErbB2 gene transcripts. Transcript levels of TNFα were significantly higher by 1.4-fold and 2.1-fold in blood cells of overweight/obese and breast cancer patients, respectively, compared with lean control subjects. Transcript levels of IL-6 were significantly higher by 2.3-fold in blood cells from breast cancer patients compared with lean control subjects with normal body mass index, and no significant difference was found in the expression level of IL-6 transcripts between overweight/obese and lean control subjects. The ErbB2 transcript levels were significantly higher by 4.72-fold compared to lean control subjects and were also significantly higher compared to overweight/obese subjects. Breast cancer and obesity are associated with altered mRNA levels of cytokines and tumor marker in peripheral blood.

Serum amyloid a is associated with obesity and estrogen receptor-negative tumors in postmenopausal women with breast cancer

Serum amyloid A (SAA) is an acute-phase protein and also an adipokine, which has been associated with the development and prognosis of breast cancer. In the present study, we investigated the association between obesity and SAA in postmenopausal women with breast cancer and its relationship with clinicopathologic characteristics of tumors. Patients were grouped as nonobese or overweight/obese based on body mass index (BMI) plus waist circumference measurement. Serum SAA concentrations were determined by high-sensitivity micro-latex agglutination tests, detected by nephelometry. Serum SAA concentrations were higher in overweight/obese (P = 0.008) patients and this condition was dependent on obesity (BMI and waist circumference), as further shown by multivariate linear regression analysis done for SAA (P = 0.01). Concentrations of SAA were also higher in patients with estrogen receptor-negative (ER(-)) tumors than in those with estrogen receptor-positive (ER(+); P = 0.033). Our results suggest a possible role for SAA in the development and prognosis of obesity-related breast cancer. A follow-up study of this population to assess overall and disease-free survival is in course and should bring contribution to evaluate the clinical role of SAA in breast cancer in the context of obesity.

Reducing breast cancer recurrence with weight loss, a vanguard trial: the Exercise and Nutrition to Enhance Recovery and Good Health for You (ENERGY) Trial

Breast cancer is the most common invasive cancer among women in developed countries. Obesity is a major risk factor for breast cancer recurrence and mortality in both pre- and postmenopausal women. Co-morbid medical conditions are common among breast cancer survivors. The Exercise and Nutrition to Enhance Recovery and Good Health for You (ENERGY) study is a 4-year randomized clinical trial of 693 overweight/obese women aged ≥21years diagnosed with any early stage breast cancer (stages I[≥1cm]-III) within the previous five years, designed to demonstrate the feasibility of achieving sustained weight loss and to examine the impact of weight loss on quality of life and co-morbidities, and to enable future exploration of biochemical mechanisms linking obesity to lower likelihood of disease-free survival. This trial is strategically designed as a vanguard for a fully-powered trial of women who will be evaluated for breast cancer recurrence and disease-free survival. Participants were recruited between 2010 and 2012 at four sites, had completed initial therapies, and had a body mass index between 25 and 45kg/m(2). The intervention featured a group-based cognitive-behavioral weight loss program with telephone counseling and tailored newsletters to support initial weight loss and subsequent maintenance, with the goal of 7% weight loss at two years. This study has high potential to have a major impact on clinical management and outcomes after a breast cancer diagnosis. This trial initiates the effort to establish weight loss support for overweight or obese breast cancer survivors as a new standard of clinical care.

Effects of a weight loss intervention on body mass, fitness, and inflammatory biomarkers in overweight or obese breast cancer survivors

BACKGROUND

Obesity is characterized by chronic mild inflammation and may influence the risk and progression of cancer.

PURPOSE

The current study is an exploratory analysis of the effect of a weight loss intervention that emphasized increased physical activity on inflammatory cytokines (tumor necrosis factor-α [TNF-α], interleukin-6 [IL-6], interleukin-8 [IL-8], and vascular endothelial growth factor [VEGF]) at the end of the 16-week intervention period in overweight breast cancer survivors.

METHODS

Study participants averaged 56 years of age (N=68). Intervention participants (n=44 vs. 24 controls) participated in a cognitive behavioral therapy-based weight management program as part of an exploratory randomized trial. The intervention incorporated strategies to promote increased physical activity and diet modification. Baseline and 16-week data included height, weight, body composition, physical activity level, and biomarkers IL-6, IL-8, TNF-α, and VEGF.

RESULTS

Weight loss was significantly greater in the intervention group than controls (-5.7 [3.5] vs. 0.2 [4.1] kg, P<0.001). Paired t tests noted favorable changes in physical activity level (P<0.001 intervention, P=0.70 control), marginally lower IL-6 levels (P=0.06 intervention, P=0.25 control) at 16 weeks for participants in the intervention group, and lower TNF-α levels for participants in the intervention (P<0.05) and control groups (P<0.001). Increased physical activity was associated with favorable changes in IL-6 for participants in the intervention group (R(2) =0.18; P<0.03).

CONCLUSION

Favorable changes in cytokine levels were observed in association with weight loss in this exploratory study with overweight breast cancer survivors.

Inhibitory effects of nitrative stress on the sulfation of 17β-estradiol and 4-methoxyestradiol by human MCF 10A mammary epithelial cells

Prolonged exposure to high level of estrogen is a known risk factor for breast carcinogenesis. It has been suggested recently that nitrative stress may be an etiologic factor for breast carcinogenesis. Since sulfation plays a major role in the homeostasis of estrogens and their metabolites, we attempted in the present study to find out whether nitrative stress may affect the homeostasis of estrogens through sulfation. Metabolic labeling experiments revealed that the amount of sulfated 17beta-estradiol or 4-methoxyestradiol decreased dramatically in MCF-10A mammary epithelial cells incubated in the presence of 3-morpholinosydnonimine (SIN-1) or diethylenetriamine NONOate (DETA NONOate), two nitric oxide donors commonly used to simulate nitrative stress conditions. In searching for the mechanism underlying the decrease of the sulfation of 17beta-estradiol and 4-methoxyestradiol, we demonstrated in an in vitro nitration experiment, that the human cytosolic sulfotransferase isoform 1E1 (SULT1E1), a major estrogen-sulfating enzyme, lost its estrogen-sulfating activity proportionately to the degree of nitration on tyrosine residues. Moreover, cell lysates prepared from MCF-10A cells treated with SIN-1 or DETA NONOate also showed much lower 4-methoxyestradiol-sulfating activities, compared with those determined with cell lysate prepared from control MCF-10A cells.

Hypertension, antihypertensive medication use, and breast cancer risk in the California Teachers Study cohort

BACKGROUND

We investigated the association between hypertension, antihypertensive (AH) medication use, and breast cancer in a large prospective study, the California Teachers Study (CTS).

METHODS

Information on history of hypertension and lifetime regular use of AH medications was collected from 114,549 women in 1995-1996. Among them, 4,151 invasive breast cancers were diagnosed between 1995 and 2006. Additional information on AH use was collected from 73,742 women in 2000-2001, and 1,714 of these women were subsequently diagnosed with breast cancer. Cox proportional hazards regression was used to estimate relative risks (RR) and 95% confidence intervals (CI) for breast cancer.

RESULTS

Use of AH medication for ≥5 years, when compared with no use, was associated with a modest increased risk of invasive breast cancer (RR = 1.18, 95%CI 1.02-1.36). This increased risk appeared to be confined to estrogen receptor (ER)-positive tumors (RR = 1.21, 95%CI 1.03-1.43) and pre-/peri-menopausal women (RR = 1.58, 95%CI 1.11-2.25).

CONCLUSIONS

Increased risk of invasive breast cancer was observed for long-term (≥5 years) AH use, and this appeared to be confined to ER + breast cancer and younger women.

PTGS2 and IL6 genetic variation and risk of breast and prostate cancer: results from the Breast and Prostate Cancer Cohort Consortium (BPC3)

Genes involved in the inflammation pathway have been associated with cancer risk. Genetic variants in the interleukin-6 (IL6) and prostaglandin-endoperoxide synthase-2 (PTGS2, encoding for the COX-2 enzyme) genes, in particular, have been related to several cancer types, including breast and prostate cancers. We conducted a study within the Breast and Prostate Cancer Cohort Consortium to examine the association between IL6 and PTGS2 polymorphisms and breast and prostate cancer risk. Twenty-seven polymorphisms, selected by pairwise tagging, were genotyped on 6292 breast cancer cases and 8135 matched controls and 8008 prostate cancer cases and 8604 matched controls. The large sample sizes and comprehensive single nucleotide polymorphism tagging in this study gave us excellent power to detect modest effects for common variants. After adjustment for multiple testing, none of the associations examined remained statistically significant at P = 0.01. In analyses not adjusted for multiple testing, one IL6 polymorphism (rs6949149) was marginally associated with breast cancer risk (TT versus GG, odds ratios (OR): 1.32; 99% confidence intervals (CI): 1.00-1.74, P(trend) = 0.003) and two were marginally associated with prostate cancer risk (rs6969502-AA versus rs6969502-GG, OR: 0.87, 99% CI: 0.75-1.02; P(trend) = 0.002 and rs7805828-AA versus rs7805828-GG, OR: 1.11, 99% CI: 0.99-1.26; P(trend) = 0.007). An increase in breast cancer risk was observed for the PTGS2 polymorphism rs7550380 (TT versus GG, OR: 1.38, 99% CI: 1.04-1.83). No association was observed between PTGS2 polymorphisms and prostate cancer risk. In conclusion, common genetic variation in these two genes might play at best a limited role in breast and prostate cancers.

Survival impact of integrative cancer care in advanced metastatic breast cancer

Integrative cancer treatment is of substantial interest to many cancer patients. Research is needed to evaluate the effects of integrative treatment on patient outcomes. We report survival data for a consecutive case series of advanced metastatic breast cancer patients who received a comprehensive clinical program combining conventional treatments with nutrition and supplementation, fitness and mind-spirit instruction at the Block Center for Integrative Cancer Treatment. Treatment outcomes using integrative care for this disease have not previously been documented; survival data will thus contribute to decisions concerning future research directions and design. Ninety consecutive patients with metastatic breast cancer diagnosed during 1984-1997 who received chemotherapy at the integrative cancer center were included. Prognostic factors, treatments and survival from onset of metastases were determined from analysis of scans, labs, pathology and medical records. The log-rank test and Cox proportional hazards analyses were used, and a Kaplan-Meier curve was calculated. All patients had metastatic disease at baseline, 96% were relapsed and 52% had received prior chemotherapy for metastatic disease. Median age at onset of metastasis was 46 years. Median survival was 38 months (95% CI 27,48). Published literature on populations with somewhat more favorable prognostic factors treated in conventional clinics showed median survivals of 20 to 23 months. Through the 1990s, median survival reported in metastatic breast cancer trials or observations generally ranged from 12 to 24 months. Five-year survival was 27% for Center versus 17% for comparison patients. Despite a higher proportion of younger and relapsed patients, survival of metastatic breast cancer patients at the Center was approximately double that of comparison populations and possibly even higher compared to trials published during this period. Explanations for the advantage relative to conventional treatment alone may include the nutritional, nutraceutical, exercise and psychosocial interventions, individually or in combination; self-selection of patients cannot be ruled out. Further research to evaluate the impact of integrative breast cancer treatment on survival is warranted.

Interleukin-1 beta and tumor necrosis factor-alpha increase ABCG2 expression in MCF-7 breast carcinoma cell line and its mitoxantrone-resistant derivative, MCF-7/MX

OBJECTIVE

In this study, we aimed to evaluate the influence of proinflammatory cytokines on ABCG2 expression and function in human MCF-7 breast cancer cell line and its mitoxantrone-resistant derivative MCF-7/MX.

METHODS

The effects of proinflammatory cytokines on ABCG2 mRNA expression were studied using real-time PCR method. Cytokine-mediated modification of ABCG2 protein expression and function was investigated by means of flow cytometry.

RESULTS

Significant inductions in the ABCG2 mRNA levels, protein expression, and activity were observed in IL-1 beta and TNF-alpha-treated MCF-7 cells. IL-6 increased ABCG2 protein, but had no effects on ABCG2 mRNA and function in MCF-7 cells. Although IL-1 beta did not alter mRNA and protein levels of the transporter in MCF-7/MX cells, ABCG2-mediated efflux was significantly increased in IL-1 beta-treated MCF-7/MX cells. TNF-alpha-treated MCF-7/MX cells also demonstrated greater ABCG2 protein expression and function without any changes in mRNA levels of the transporter. Neither ABCG2 mRNA nor its protein expression and function were affected by IL-6 in MCF-7/MX cells.

CONCLUSION

IL-1 beta and TNF-alpha induce ABCG2 mRNA and protein expression and increase its activity in breast cancer cell line MCF-7. In MCF-7/MX cells these cytokines modulate ABCG2 protein expression and/or function, but they have no influence on the transporter mRNA levels.

Functions of normal and malignant prostatic stem/progenitor cells in tissue regeneration and cancer progression and novel targeting therapies

This review summarizes the recent advancements that have improved our understanding of the functions of prostatic stem/progenitor cells in maintaining homeostasis of the prostate gland. We also describe the oncogenic events that may contribute to their malignant transformation into prostatic cancer stem/progenitor cells during cancer initiation and progression to metastatic disease stages. The molecular mechanisms that may contribute to the intrinsic or the acquisition of a resistant phenotype by the prostatic cancer stem/progenitor cells and their differentiated progenies with a luminal phenotype to the current therapies and disease relapse are also reviewed. The emphasis is on the critical functions of distinct tumorigenic signaling cascades induced through the epidermal growth factor system, hedgehog, Wnt/beta-catenin, and/or stromal cell-derived factor-1/CXC chemokine receptor-4 pathways as well as the deregulated apoptotic signaling elements and ATP-binding cassette multidrug transporter. Of particular therapeutic interest, we also discuss the potential beneficial effects associated with the targeting of these signaling elements to overcome the resistance to current treatments and prostate cancer recurrence. The combined targeted strategies toward distinct oncogenic signaling cascades in prostatic cancer stem/progenitor cells and their progenies as well as their local microenvironment, which could improve the efficacy of current clinical chemotherapeutic treatments against incurable, androgen-independent, and metastatic prostate cancers, are also described.

Predictors of inflammation in response to anthracycline-based chemotherapy for breast cancer

Although chemotherapy for breast cancer can increase inflammation, few studies have examined predictors of this phenomenon. This study examined potential contributions of demographics, disease characteristics, and treatment regimens to markers of inflammation in response to chemotherapy for breast cancer. Thirty-five women with stage I-III-A breast cancer (mean age 50 years) were studied prior to cycle 1 and prior to cycle 4 of anthracycline-based chemotherapy. Circulating levels of inflammatory markers with high relevance to breast cancer were examined, including C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-alpha), Interleukin-1 receptor antagonist (IL1-RA), vascular endothelial growth factor (VEGF), soluble intercellular adhesion molecule-1 (sICAM-1), Interleukin- (IL-6), soluble P-selectin (sP-selectin), and von Willebrand factor (vWf). Chemotherapy was associated with elevations in VEGF (p < or = 0.01), sICAM-1 (p < or = 0.01), sP-selectin (p < or = 0.02) and vWf (p < or = 0.05). Multiple regression analysis controlling for age and body mass index (BMI) showed that higher post-chemotherapy levels of inflammation were consistently related to higher pre-chemotherapy levels of inflammation (ps < or =0.05) as well as to certain disease characteristics. Post-chemotherapy IL-6 levels were higher in patients who had larger tumors (p < or = 0.05) while post-chemotherapy VEGF levels were higher in patients who had smaller tumors (p < or = 0.05). Post-chemotherapy sP-selectin levels were highest in women who had received epirubicin, cytoxan, 5-fluorouracil chemotherapy (p < or = 0.01). These findings indicate that chemotherapy treatment can be associated with elevations in certain markers of inflammation, particularly markers of endothelial and platelet activation. Inflammation in response to chemotherapy is most significantly related to inflammation that existed prior to chemotherapy but also potentially to treatment regimen and to certain disease characteristics.

C-Reactive Protein and Risk of Breast Cancer

Chronic inflammation is hypothesized to be associated with breast cancer development. However, data evaluating the association between C-reactive protein (CRP), a marker of systemic inflammation, and breast cancer risk are sparse. In the Women's Health Study, 27,919 apparently healthy women aged 45 years and older who were free of cancer and cardiovascular disease had plasma CRP levels measured at baseline. During a mean of 10 years of follow-up, a total of 892 women developed invasive breast cancer. All statistical tests were two-sided. Baseline plasma CRP level was not statistically significantly associated with breast cancer risk (highest versus lowest quintile of CRP, multivariable hazard ratio = 0.90, 95% confidence interval = 0.71 to 1.16; P(trend) = .19; crude incidence rates: 273 versus 305 per 100,000 person-years). Our data suggest that baseline plasma CRP levels are not associated with the increased risk of breast cancer in apparently healthy women.

C-Reactive Protein in Nipple Aspirate Fluid

BACKGROUND

Proteins expressed in nipple aspirate fluid (NAF) have been associated with breast cancer risk and may serve to detect inflammatory or premalignant states. Obesity, hyperlipidemia, and metabolic syndrome are associated with increased rates of breast cancer and are systemic markers of chronic inflammation.

OBJECTIVE

The aim of this study was to determine if one NAF protein, C-reactive protein (CRP), associated elsewhere in the human with cancer, relates to reproductive, nutrition, and body composition and activity factors.

METHODS

Women (n = 59) aged 30 to 64 years from the midwestern United States and Kenya were evaluated regarding the relation between reproductive (age, pregnancy, and breast-feeding indices), nutrition (serum lipids, serum, or NAF carotenoid), body composition and activity (activity, waist-hip ratio, fat percentage (% fat), and body mass index [BMI]) factors and CRP in NAF.

RESULTS

Age at first pregnancy (p < .05), gravidity (p < .05), wean time from breast-feeding last baby (p < .05), serum triglycerides (p = .01), % fat (p < .05), and BMI (p < .05) were related significantly to CRP levels in NAF. A model derived from selective women's reproductive, nutritional, and body composition and activity factors significantly (p < .05) accounted for the variance in breast microenvironment inflammation as measured by CRP in NAFs.

DISCUSSION

Detecting CRP in NAF may indicate local mammary inflammation, which has been associated with carcinogenesis. Specific NAF risk modeling that addresses reproductive, nutritional, and body composition and activity factors may be used for further advances in the prevention of breast cancer and the early detection and treatment of the disease.

The Farnesoid X Receptor Is Expressed in Breast Cancer and Regulates Apoptosis and Aromatase Expression

Bile acids are present at high concentrations in breast cysts and in the plasma of postmenopausal women with breast cancer. The farnesoid X receptor (FXR) is a member of the nuclear receptor superfamily that regulates bile acid homeostasis. FXR was detected in normal and tumor breast tissue, with a high level of expression in ductal epithelial cells of normal breast and infiltrating ductal carcinoma cells. FXR was also present in the human breast carcinoma cells, MCF-7 and MDA-MB-468. Activation of FXR by high concentrations of ligands induced MCF-7 and MDA-MB-468 apoptosis. At lower concentrations that had no direct effect on viability, the FXR agonist GW4064 induced expression of mRNA for the FXR target genes, small heterodimer partner (SHP), intestinal bile acid binding protein, and multidrug resistance-associated protein 2 (MRP-2), and repressed the expression of the SHP target gene aromatase. In contrast to MRP-2, mRNA for the breast cancer target genes MDR-3, MRP-1, and solute carrier transporter 7A5 were decreased. Although multidrug resistance transporters were regulated and are known FXR target genes, GW4064 had no effect on the cell death induced by the anticancer drug paclitaxel. Our findings show for the first time that FXR is expressed in breast cancer tissue and has multiple properties that could be used for the treatment of breast cancer.