Diet and breast cancer

Interleukin-6 selectively induces drug metabolism to potentiate the genotoxicity of dietary carcinogens in mammary cells

Breast cancer is the most commonly diagnosed malignancy in females, the etiology being multifactorial and includes the role of lifestyle exposure to DNA-damaging chemicals such as dietary carcinogens benzo (a) pyrene (BaP) and 2-amino-1-methyl-6-phenylimidazo [4, 5-b] pyridine (PhIP). Both compounds require cytochrome P450 (CYP)-mediated metabolic activation to DNA-damaging species, and both induce transcriptional responses through the nuclear receptors Aryl hydrocarbon receptor (AhR) and estrogen receptor α (ERα). BaP and PhIP are mammary carcinogens in rodents. Clinically, circulating IL-6 expression is linked with poor prognosis of cancer and 35% of the deaths in breast cancer are linked with inflammation. The objective of this work was to investigate the molecular toxicology and local activation of BaP and PhIP in the presence of IL-6. Our laboratory has previously reported that miR27b can regulate CYP1B1 expression in colorectal cells, here we have investigated if this mechanism is working in mammary cell models, MCF-7 and MDA-MB-231 cells. Treatment (24 h) of cells with BaP (10 nM-10 µM) and PhIP (100 nM-100 µM) significantly induced genetic damage (micronuclei formation) in a dose-dependent manner in both cell lines. This effect was potentiated in the presence of human IL-6 at concentrations reported to be expressed in clinical breast cancer. On its own, IL-6 treatment failed to induce micronuclei frequency above the control levels in these cells. Compared to BaP or PhIP treatment alone, IL-6 plus BaP or PhIP selectively induced CYP1B1 significantly in both cell lines. Additionally, miR27b expression was downregulated by IL-6 treatments and transfection with miR27b inhibitor confirmed that miR27b is a regulator of CYP1B1 in both cell lines. These data show that BaP- and PhIP-induced DNA damage in mammary cells is potentiated by the inflammatory cytokine IL-6 and that inflammation-induced CYP expression, specifically CYP1B1 via miR27b, is responsible for this effect.

Regional Estimates of Breast Cancer Burden in Italy

Aims and background

Breast cancer is the most common cancer and the leading cause of cancer death among women. Knowledge of the present and future burden of the disease at a regional and national scale is a major issue in Italy, where the frequency and coverage of screening programs vary considerably across the country. This study presents estimates and projections of the female breast cancer incidence, prevalence and mortality for Italy and all Italian regions in the period 1970-2010.

Methods

The estimates were obtained by applying the MIAMOD method, a statistical back-calculation approach to derive incidence and prevalence figures from mortality and relative survival data. Published data from the Italian cancer registries were modelled to obtain regional and national estimates of breast cancer survival.

Results

Breast cancer mortality has been declining from the late 1980s in the northern-central regions and from the mid 1990s in the southern regions Puglia, Sicilia and Sardegna. Stable mortality rates are estimated for the other southern regions in the 2000's first decade. The incidence rate in Italy is estimated as increasing until the late 1990s, and stable thereafter (93 per 100,000). The incidence curve is also estimated to flatten in many northern-central regions from the late 1990s or later. Rising incidence trends are estimated in all southern regions, with the exception of Puglia. About 8,500 deaths, 37,000 new diagnoses and 416,000 prevalent cases for breast cancer are estimated among Italian women in 2005. In the same year, the proportion of prevalent cases in the northern area (1,221 per 100,000) is about twice that estimated in the South (685 per 100,000).

Discussion

The geographical variation in female breast cancer burden can be explained by the unequal distribution of screening. A more widespread screening activity in the southern regions would help to bridge the gap between northern-central and southern regions. Continuous monitoring of regional epidemiological indicators for breast cancer is crucial to evaluate the effect of different health measures taken to control breast cancer in Italy.

Nutritional risk factors and status of serum 25(OH)D levels in patients with breast cancer: A case control study in India

To study the nutritional risk factors and status of serum 25(OH)D levels in patients with breast cancer. A total of 100 women (cases) with confirmed breast cancer (BC) matched with equal number of healthy females (controls) of similar age and socioeconomic status (SES) were included in study. Controls included were nonbreast cancer patients who accompanied the patients to a tertiary care hospital. All the subjects (cases and controls) were administered a questionnaires to collect data on socioeconomic status, dietary pattern and the frequency of food consumption using a validated food frequency questionnaire. Anthropometric assessment was done for waist and hip circumference to calculate waist to hip ratio (WHR). Non fasting blood samples were collected for serum 25-hydroxyvitamin D [25(OH)D] levels estimation using chemiluminescent immunoassay technique and total serum calcium levels by colorimetric assay technique. Serum 25(OH)D and total calcium levels were expressed in ng/ml and mg/dl. Vitamin D deficiency was defined as per the guidelines set by United States Endocrine Society. The mean age of cases and controls was 45±9 and 46±10 years respectively. On multivariate analysis, an inverse association with BC was found for less frequency of fruits consumption with an adjusted (ORs, 95% CI) (2.7, 0.5-15.7) respectively. Mushroom intake was inversely associated with risk of BC (ORs, 95% CI) (5.6, 1.9-16.6). Saturated fat intake and high WHR were significantly associated with high risk of BC with adjusted ORs, 95% CI of (3.4, 1.4-8.1) and (5, 1.4-17). A significant association (p<0.05) was found between low serum 25(OH)D levels and the risk of BC with adjusted ORs, 95% CI of (2.5, 0.9-7.4). Majority of the patients with BC were suffering from vitamin D deficiency. Dietary intake of mushrooms containing vitamin D naturally was found to be associated with decreased risk of breast cancer. A significant association was found between low serum 25(OH)D levels (<20ng/ml) with the risk of BC. Obesity as a consequence of nutritional risk factors determined by higher WHR was found to be significantly associated with the risk of BC.

Fast food fever: reviewing the impacts of the Western diet on immunity

While numerous changes in human lifestyle constitute modern life, our diet has been gaining attention as a potential contributor to the increase in immune-mediated diseases. The Western diet is characterized by an over consumption and reduced variety of refined sugars, salt, and saturated fat. Herein our objective is to detail the mechanisms for the Western diet's impact on immune function. The manuscript reviews the impacts and mechanisms of harm for our over-indulgence in sugar, salt, and fat, as well as the data outlining the impacts of artificial sweeteners, gluten, and genetically modified foods; attention is given to revealing where the literature on the immune impacts of macronutrients is limited to either animal or in vitro models versus where human trials exist. Detailed attention is given to the dietary impact on the gut microbiome and the mechanisms by which our poor dietary choices are encoded into our gut, our genes, and are passed to our offspring. While today's modern diet may provide beneficial protection from micro- and macronutrient deficiencies, our over abundance of calories and the macronutrients that compose our diet may all lead to increased inflammation, reduced control of infection, increased rates of cancer, and increased risk for allergic and auto-inflammatory disease.

Health behavior change among breast cancer patients

OBJECTIVES

Changes in health behavior among women with breast cancer with respect to food intake, exercise and smoking habits are considered. We aimed to analyze (1) significant modifications of these behaviors about a year after breast cancer surgery and (2) the impact of social, medical and behavioral patient characteristics on these changes.

METHODS

Data were derived from a longitudinal study of 229 women (age < 70) in Germany with a first manifestation of breast cancer. Food intake, physical activity and smoking were assessed by means of personal interviews immediately after surgery (T0) and 14 months later (T1).

RESULTS

The intake of fruits and vegetables and physical exercise increased significantly over the observation period. Socio-demographic and medical parameters were largely irrelevant for behavioral changes while smoking status turned out as most important for changes in daily fruit consumption.

CONCLUSIONS

The results demonstrate that breast cancer patients change their lifestyle habits in a significant way even without intervention. Patients who smoke are in particular need of professional support to implement health-promoting behavior, and intervention should especially focus on this group.

Do alterations in mitochondrial DNA play a role in breast carcinogenesis?

A considerable body of evidence supports a role for oxidative stress in breast carcinogenesis. Due to their role in producing energy via oxidative phosphorylation, the mitochondria are a major source of production of reactive oxygen species, which may damage DNA. The mitochondrial genome may be particularly susceptible to oxidative damage leading to mitochondrial dysfunction. Genetic variants in mtDNA and nuclear DNA may also contribute to mitochondrial dysfunction. In this review, we address the role of alterations in mtDNA in the etiology of breast cancer. Several studies have shown a relatively high frequency of mtDNA mutations in breast tumor tissue in comparison with mutations in normal breast tissue. To date, several studies have examined the association of genetic variants in mtDNA and breast cancer risk. The G10398A mtDNA polymorphism has received the most attention and has been shown to be associated with increased risk in some studies. Other variants have generally been examined in only one or two studies. Genome-wide association studies may help identify new mtDNA variants which modify breast cancer risk. In addition to assessing the main effects of specific variants, gene-gene and gene-environment interactions are likely to explain a greater proportion of the variability in breast cancer risk.

Does a higher ratio of serum calcium to magnesium increase the risk for postmenopausal breast cancer?

Breast cancer is the most commonly diagnosed cancer among United States (US) women. Established risk factors explain only about 13% of breast cancer incidence among women in the US. Thus, the cause of most cases of breast cancer remains unknown. In postmenopausal women, serum calcium (Ca) and serum magnesium (Mg) play an important role in skeletal health, cell proliferation and cancer. Mg is essential for DNA duplication and repair and Mg deficiency favors DNA mutations leading to carcinogenesis. Dietary intake of Mg in the US is less than the recommended amount, and the deficit is more pronounced in older individuals where gastrointestinal and renal mechanisms for Mg conservation are not as efficient. Furthermore, healthy postmenopausal women are frequently recommended to take supplemental Ca, but not Mg and vitamin D to maintain bone and overall health. Most women with hormone sensitive breast cancer are recommended to take aromatase inhibitors, which causes bone loss and thus are generally prescribed Ca and vitamin D, but not Mg. Although the association between serum Ca and breast cancer risk remains controversial, we hypothesize that this may be because Mg levels have not been accounted for. Mg level directly influences transient receptor potential melastatin 7 (TRPM7) related Ca influx, calcium-adenosine triphosphatase (Ca-ATP) levels, and cell proliferation, and thereby could lead to cancer. Thus a high serum Ca/Mg ratio is more appropriate and alterations in this ratio could lead to increased development of new and recurrent breast cancer.

Adolescent diet in relation to breast cancer risk among premenopausal women

BACKGROUND

Although the association between adult diet and breast cancer has been investigated extensively, large prospective studies have generally not shown a direct link between intakes of carbohydrate, fat, fiber, and other nutrients and risk of breast cancer. Adolescence may be a period of increased susceptibility to risk factors that predispose to breast cancer. Dietary risk factors could therefore be more important during early life than later in adulthood.

METHODS

This is a prospective observational study of 39,268 premenopausal women in the Nurses' Health Study II who completed a 124-item food frequency questionnaire on their diet during high school (HS-FFQ) in 1998, at which time participants were 34 to 53 years of age. Cox proportional hazards regression was used to estimate relative risks and 95% CIs.

RESULTS

Four hundred fifty-five incident cases of invasive breast cancer were diagnosed between 1998 and 2005. Compared with women in the lowest quintile of intake, the relative risk of breast cancer in the highest quintile of adolescent total fat consumption was 1.35 (95% confidence interval, 1.00-1.81). Adolescent consumption of saturated, monounsaturated, polyunsaturated, and trans fats was not significantly associated with breast cancer risk. Total dairy, milk, carbohydrate intake, glycemic index, glycemic load, and fiber consumed during adolescence were not significantly related to breast cancer incidence.

CONCLUSION

Dietary fat consumed during adolescence may be associated with an elevated risk of breast cancer. Further studies to assess this relationship among postmenopausal women, and confirm these results in premenopausal women, are needed.

Risk factors for breast cancer among Filipino women in Manila

Age-adjusted incidence rates of breast cancer vary greatly worldwide with highest rates found in the typically 'westernised' countries of North America and Europe. Much lower rates are observed in Asian and African populations but an exception to this has been reported for the Manila Cancer Registry in the Philippines. The reason for this high rate is unknown but may be associated with the change in lifestyle that has occurred in urban Manila since the 1960s. In 1995, a randomised controlled trial was set up in Manila to evaluate the feasibility of a screening intervention by clinical breast examination as an alternative to mammography. The cohort of 151,168 women was followed-up to 2001 for cancer incidence and a nested case-control study carried out. This aimed to evaluate the increase in breast cancer risk associated with known risk factors. Increased risks were seen for a high level of education (OR = 1.9 95%CI 1.1-3.3 for education stopped at > or =13 versus <13 years), nulliparity (OR = 5.0 95% CI 2.5-10.0 for nulliparity versus five or more children), and late age at first birth (OR = 3.3 95% CI 1.3-8.3 for age > or =30 versus <20 years). We found no association with excess body weight, height, use of exogenous hormones or alcohol consumption. From this study, the recognised "classical" risk factors do not fully explain the high breast cancer incidence in Metro Manila, especially when compared to other urban Asian populations. We conclude that it is too simplistic to ascribe the high risk to 'westernisation'.

Meat, eggs, dairy products, and risk of breast cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort

BACKGROUND

A Western diet is associated with breast cancer risk.

OBJECTIVE

We investigated the relation of meat, egg, and dairy product consumption with breast cancer risk by using data from the European Prospective Investigation into Cancer and Nutrition (EPIC).

DESIGN

Between 1992 and 2003, information on diet was collected from 319,826 women. Disease hazard ratios were estimated with multivariate Cox proportional hazard models.

RESULTS

Breast cancer cases (n = 7119) were observed during 8.8 y (median) of follow-up. No consistent association was found between breast cancer risk and the consumption of any of the food groups under study, when analyzed by both categorical and continuous exposure variable models. High processed meat consumption was associated with a modest increase in breast cancer risk in the categorical model (hazard ratio: 1.10; 95% CI: 1.00, 1.20; highest compared with lowest quintile: P for trend = 0.07). Subgroup analyses suggested an association with butter consumption, limited to premenopausal women (hazard ratio: 1.28; 95% CI: 1.06, 1.53; highest compared with lowest quintile: P for trend = 0.21). Between-country heterogeneity was found for red meat (Q statistic = 18.03; P = 0.05) and was significantly explained (P = 0.023) by the proportion of meat cooked at high temperature.

CONCLUSIONS

We have not consistently identified intakes of meat, eggs, or dairy products as risk factors for breast cancer. Future studies should investigate the possible role of high-temperature cooking in the relation of red meat intake with breast cancer risk.

Incidence of breast cancer in Italy: mastectomies and quadrantectomies performed between 2000 and 2005

OBJECTIVES

We aimed to determine the incidence of women's breast cancer in Italy without using statistical approximations.

METHODS

We analyzed the national hospitalizations database at the Ministry of Health to calculate the number of major surgeries in Italian women (mastectomies and quadrantectomies) due to breast cancer between 2000 and 2005, overall and by age groups (<44, 45-64, 65-74 and >or= 75 years old).

RESULTS

Over the six years examined, an overall number of 100,745 mastectomies and 168,147 quadrantectomies were performed. A total of 41,608 major surgeries due to breast cancer were performed in the year 2000 and this number rose to 47,200 in 2005, with a 13.4% increase over six years.

CONCLUSION

by analyzing the hospitalizations database concerning major breast surgery, incidence of breast cancer in Italy was found to be 26.5% higher than the official estimations which have been computed using statistical models (namely 47,200 vs. 37,300 cases in year 2005).

Impact of diet on breast cancer risk

PURPOSE OF REVIEW

Breast cancer is the most common female cancer in Western Europe and North America, and becoming an increasing problem in developing countries such as India and China. We review recent studies (published 1 January 2007-31 August 2008) on the impact of diet on breast cancer risk.

RECENT FINDINGS

Recent studies have focused on the controversial association for dietary fat and breast cancer as well as the role of newer aspects such as glycemic index, dietary patterns and diet-gene interactions. Evidence that some of the associations may be modified by oestrogen and progesterone receptor status has been presented. Still, only alcohol intake, being overweight and weight gain have shown consistent and strong positive associations with breast cancer risk. The reasons for the null or weak associations often observed regarding diet and breast cancer might be several. For example, there may be no causal association, or existing associations may be masked by measurement error, timing of dietary exposure and differences according to tumour characteristics or diet-gene interactions.

SUMMARY

Numerous epidemiological studies on diet and breast cancer have been published during our review period. Still, only alcohol intake, being overweight and weight gain have shown consistent and strong positive associations with breast cancer risk.

Adult daughters' reports of breast cancer risk reduction and early detection advice received from their mothers: an exploratory study

OBJECTIVE

Awareness of cancer family history is dependent upon communication between family members. Communication of this information and related decision-making could be important factors influencing breast cancer risk reduction and early detection behaviors. Using survey data from 2328 women (mean age 62.5 years) from 372 families enrolled in the Minnesota breast cancer family study, we explored adult daughter's reports of breast cancer risk reduction advice received from their mothers.

METHODS AND RESULTS

Approximately 212 (9%) of respondents reported receiving breast cancer risk reduction advice from their mothers and 130 (89%) reported acting upon such advice. Having a mother or first degree relative (FDR) with a history of breast cancer was significantly correlated with following advice to a higher degree as compared with those not having such family history (p=0.003). Most frequently reported types of advice were to have mammograms (36%) and to have clinical breast exams (35%). Using multivariable logistic regression and after accounting for non-independence of the sample, significant independent correlates of receiving advice included younger age, having an affected mother, and having a higher perceived breast cancer risk. Receiving advice was also correlated with engaging in a higher number of health promoting behaviors and ever having received a mammogram.

CONCLUSIONS

Our preliminary findings are consistent with social influence theory and suggest that mother-daughter communication about reducing risk, especially among those having a FDR with breast cancer, could be a potential pathway through which breast cancer family history is associated with the adoption of breast cancer screening and risk reduction behaviors.

Epidemiology, genetics, and risk evaluation of postmenopausal women at risk of breast cancer

Breast cancer risk factors have been studied for the past three decades, and the single most important risk factor is age. Hormonally linked adult reproductive and anthropometric risk factors contribute to the etiology of postmenopausal breast cancer. The risk of breast cancer increases among women older than 50 years of age who have benign breast disease, especially those with atypical ductal or lobular hyperplasia. Lobular carcinoma in situ increases risk significantly, as do a family history of breast cancer in first-degree relatives and the presence of BRCA1 or BRCA2 mutations. Diet, exercise, and environmental factors play a very small role in overall risk. Mammographic breast density increases relative risk fivefold among women with the highest density, and breast cancer risk is two to three times greater in women with elevated serum levels of estradiol or testosterone. Multivariate risk models allow determination of composite relative risks and cumulative lifetime risk, although improved models for African American women are required. For postmenopausal women, newer risk models are being developed and validated that include age, breast density, race, ethnicity, family history of breast cancer, a previous breast biopsy, body mass index, age at onset of natural menopause, hormone therapy, and previous false-positive mammography. A simpler model that includes only age, breast cancer in first-degree relatives, and previous breast biopsy performs well for estrogen receptor-positive breast cancer in postmenopausal women. As many as 10 million women in the United States are at increased risk, and clinicians are obligated to identify these women and manage their risk appropriately.

Urinary metalloproteinases: noninvasive biomarkers for breast cancer risk assessment

Matrix metalloproteinases (MMP) and a disintegrin and metalloprotease 12 (ADAM 12) can be detected in the urine of breast cancer patients and provide independent prediction of disease status. To evaluate the potential of urinary metalloproteinases as biomarkers to predict breast cancer risk status, urine samples from women with known risk marker lesions, atypical hyperplasia and lobular carcinoma in situ (LCIS), were analyzed. Urine samples were obtained from 148 women: 44 women with atypical hyperplasia, 24 women with LCIS, and 80 healthy controls. MMP analysis was done using gelatin zymography and ADAM 12 analysis was done via immunoblotting with monospecific antibodies and subsequent densitometric measurement. Positive urinary MMP-9 levels indicated a 5-fold risk of atypical hyperplasia and >13-fold risk of LCIS compared with normal controls. Urinary ADAM 12 levels were significantly elevated in women with atypical hyperplasia and LCIS from normal controls, with receiver operating characteristic curve analysis showing an area under the curve of 0.914 and 0.950, respectively. To assess clinical applicability, a predictive index was developed using ADAM 12 in conjunction with Gail risk scores for women with atypia. Scores above 2.8 on this ADAM 12-Gail risk prediction index score are predictive of atypical hyperplasia (sensitivity, 0.976; specificity, 0.977). Our data suggest that the noninvasive detection and analysis of urinary ADAM 12 and MMP-9 provide important clinical information for use as biomarkers in the identification of women at increased risk of developing breast cancer.

Nutrition and immunity in cancer

The purpose of this article is to give a general overview of the effects of nutrition on the development of cancer as well as part of a therapeutic approach. There is much evidence that diet and lifestyle can alter the risk of cancer development as is the case for many other chronic diseases. This may be through a direct action on the immune system, either by enhancing or suppressing it, as well as on the development of the tumour itself, by modulating gene expression or by antioxidant activity. Protective effects can be achieved by adequate intakes of vitamins A and C, beta-carotene, selenium and n-3 fatty acids among others, while negative effects are found mainly with high intakes of n-6 and saturated fatty acids. Weight gain, obesity and lack of regular physical activity have also been associated with an increased risk of cancer. The protective effects are best observed when adequate diet and lifestyle are present together. With respect to the therapeutic role of nutrition in cancer, it has been observed that the use of pre- or post-operative enteral or parenteral nutrition may improve patients' survival rates and quality of life; however, more research is needed in this particular area. Breast, colon, rectum, prostate, stomach and lung are the types of cancer most commonly associated with diet or dietary components.