Breast cancer: hormones and other risk factors

Tissue Microarray Immunohistochemical Staining for Androgen Receptor in Breast Cancer in a Ghanaian Cohort

BACKGROUND

Despite the advancement in therapy, breast cancer still remains the most common malignancy in women globally due in part to its heterogeneity. Triple-negative breast cancer (TNBC) represents up to 20% of all breast cancer variants, an aggressive disease with poorer outcomes compared to other breast cancer subtypes. No targeted therapies are currently approved for TNBC, and newer treatment approaches are seriously needed. Androgen receptor (AR), another hormonal receptor, is often expressed in breast cancer, and its role depends on the relative levels of circulating estrogens and androgens. This study aimed to assess the expression of AR in breast cancer in a tertiary hospital in Ghana.

METHODOLOGY

Immunohistochemical staining for AR was performed on tissue microarray (TMA) blocks, of which estrogen receptor, progesterone receptor, and Her-2/neu had already been done. 197 cases were suitable for the study. Results from the immunostaining were analyzed using the SPSS version 23 for descriptive statistics and correlations (χ2 and Pearson tests).

RESULTS

197 TMA cases were used. TNBCs constitute 61.9% of the cancers. The majority of these tumors were grade III, ductal carcinoma NST. The mean age was 49.86 ± 14.09, and the modal age group was 40-49 years. Our cases showed 23% AR expression in triple-negative cancers. The study also established that AR is more frequently expressed in low-grade tumors compared to high-grade ones.

CONCLUSION

There is an appreciable level of AR expression in our cases; however, most are quadruple negative. However, AR is more frequently expressed in low-grade tumors than high-grade ones.

Comparison of genetic diversity and phylogenetic structure of BRCA1 gene of some domestic and wild sheep breeds in different countries

BRCA1 gene plays an important role in DNA damage repair, cell cycle, and transcription process regulation; hence it's called gate keeper. The current research aims to perform bioinformatics analyzes of the BRCA1 gene of different breeds of domestic and wild sheep from 49 breeds in 14 countries using the NCBI genome database. The desired sequences were aligned using MEGA11 software and a phylogenetic tree was drawn by Neighbor-Joining method. The number of mutations, nucleotide diversity, and haploid diversity were also analyzed using Dnaspv5 software. The analyses showed 296 polymorphisms, which led to the creation of 45 different haplotypes with a haplotype diversity of 0.035. Nucleotide diversity and average nucleotide differences among breeds were estimated as 0.259 and 0.052, respectively. The average genetic distance within the population of countries was calculated as 0.052. The amount of sequence conservation in this research was 0.313 on average, which indicates the high polymorphism of this gene and the emergence of new proteins. Tajima's D value in Tajima's neutrality test was -2.421, which was significant (p < 0.05). One of the reasons for the high genetic diversity in Iran's wild sheep population is the existence of forests and open environments, which prevent genetic drift and reduce inbreeding.

Breast Cancer Prevention: The Key Role of Population Screening, Breast Self-Examination (BSE) and Technological Tools. Survey of Italian Women

Breast cancer is the most common tumor among women worldwide and still remains the leading cause of death in women in Italy. Although survival from this pathology has increased, this disease and its treatment can have lasting or delayed effects that can greatly affect a woman's quality of life. Primary and secondary prevention are currently the best strategies to combat this cancer: improved lifestyle, early adherence to screening, Breast Self-Examination (BSE), and even now the use of technology, have become among the most important tools to ensure increasingly early diagnosis of this disease, which is a major cause of suffering and premature mortality in women. Indeed, early diagnosis of the disease can lead to a good prognosis and a high survival rate. This study investigates the attitude of Italian women to perform clinical checkups aimed at cancer prevention, particularly adherence to free screening programs offered by the National Health Service (NHS) for women in the 50-69 age group. The knowledge, use and emotional approach toward BSE as a screening tool and the use of dedicated apps for this purpose are also investigated. Low adherence to screening programs, lack of BSE practice, and nonuse of dedicated apps are just some of the results observed in this study. Therefore, it becomes essential to spread the culture of prevention, cancer awareness and the importance of screening throughout life.

Profile of Male Breast Cancer in Makkah Region of Saudi Arabia: A 4-Year Retrospective Analysis of Radiology and Histopathology

Background

Mammography is a method widely used for the diagnosis of breast disorders in women and may help detect breast cancer in its early stages. Male breast cancer often remains undiagnosed or is poorly controlled until serious complications arise; therefore, the use of screening methods is needed to help with early diagnosis.

Methods

From a total of 1,667 registered mammography cases screened, 17 male breast disease cases were included in this study. Mammography and ultrasound data were analyzed by Statistical Package of Social Sciences v.22 (SPSS). Diagnosis was made following biopsy in suspicious cases, and histopathological and immunological findings of all such patients were obtained for final diagnosis.

Results

The mean age of the patients was 35 years (range, 14-70 years); 17.6% of the cases were aged 37 yrs, and 2 cases were aged 51 and 52 yrs. Of the 17 cases, 11 had breast lesions, and skin thickening was observed in only 1 case. The different patterns of lesions detected were asymmetry of the parenchyma, mastitis, and hamartoma (n = 1 each), malignant lesions (n = 2), and gynecomastia (n = 6). According to the BI-RADS categorization, 8 cases were benign, one case was probably benign, and 2 cases were likely malignant. In the 2 cases with malignant lesions, pathological diagnosis was made after hematoxylin and eosin and immunocytochemistry examination as invasive ductal carcinoma (IDC) of no special type (NST), grade II and grade III.

Conclusions

Most breast lesions in this study population were benign, while IDC was the most common malignancy encountered. Mammography is currently the most accurate and cost-effective method for detecting breast lesions. The findings of our study may help increase awareness of male breast cancer and encourage Saudi men at risk to perform self-breast exam and undergo routine breast screening.

In-vitro Cytotoxicity and Aromatase Inhibitory Activity of Flavonoids: Synthesis, Molecular Docking and In-silico ADME Prediction

BACKGROUND

Many natural and synthetic flavonoids have been studied and documented by inhibiting aromatase enzymes for their anti-cancer activity against breast carcinoma. The aromatase enzyme is a possible target for the estrogen's positive breast cancer receptor.

OBJECTIVE

Hence, a series of flavonoids have been synthesized and assessed for their in vitro cytotoxicity and aromatase inhibitory activity.

METHODS

39 flavonoids were synthesized and characterized by spectroscopic techniques, and their computational study was performed using the maestro version of the Schrodinger. In-silico ADME properties were checked by QikPro software. A total of 18 compounds were evaluated based on the docking score using cytotoxicity assay in human breast cancer cell line MCF-7.

RESULTS

Of the 18 compounds tested, 07 compounds, namely 2b, 8b, 14b, 15b, 19b, 24b, and 30b flavonoids were found to be more active with their IC₅₀ values of 20.73 μM, 1.636 μM, 16.08 μM, 22.02 μM, 15.75 μM, 0.345 μM and 16.08 μM, respectively, compared with the reference drug letrozole. The in-vitro aromatase inhibitory activity of six compounds 2b, 8b, 14b, 19b, 24b, and 30b was conducted using a fluorogenic assay kit. The values of IC₅₀ for compounds 2b and 24b were found to be 0.31 μM and 0.36 μM, respectively.

CONCLUSION

Therefore, it was concluded that compounds 2b and 24b had a potent inhibitory effect of aromatase compared with letrozole with an IC₅₀ value of 0.86 μM. At the same time, the other compounds 8b, 14b, 30b, and 19b were considered to have similar aromatase inhibitory activity. Hence, their essential aromatase inhibitory activities make them good lead candidates for developing potent inhibitors of aromatase.

Docking and molecular dynamics predicted B-DNA and dihydropyrimidinone selenoesters interactions elucidating antiproliferative effects on breast adenocarcinoma cells

Dihydropyrimidinones have demonstrated different biological activities including anticancer properties. Cytotoxic potential and antiproliferative potential of new dihydropyrimidinone-derived selenoesters (Se-DHPM) compounds were assessed in vitro against the breast adenocarcinoma cells (MCF-7). Among the eight Se-DHPM compounds tested just 49A and 49F were the most cytotoxic for MCF-7 and the most selective for the non-tumor strain (McCoy) and reduced cell viability in a time- and concentration-dependent manner. Compounds 49A and 49F increased the rate of cell death due to apoptosis and necrosis comparatively to the control, however only the 49F showed antiproliferative potential, reducing the number of colonies formed. In the molecular assay 49A interacts with CT-DNA and caused hyperchromism while 49F caused a hypochromic effect. The intercalation test revealed that the two compounds caused destabilization in the CT-DNA molecule. This effect was evidenced by the loss of fluorescence when the compounds competed and caused the displacement of propidium iodide. Simulations (docking and molecular dynamics) using B-DNA brought a greater understanding of ligand-B-DNA interactions. Furthermore, they predicted that the compounds act as minor groove ligands that are stabilized through hydrogen bonds and hydrophobic interactions. However, the form of interaction foreseen for 49A was more energetically favorable and had more stable hydrogen bonds during the simulation time. Despite some violations foreseen in the ADMET for 49F, the set of other results point to this Se-DHPM as a promising leader compound with anti-tumor potential for breast cancer.Communicated by Ramaswamy H. Sarma.

In-Vitro Fertilization Impact on the Risk of Breast Cancer: A Review Article

Background

Due to the increasing prevalence of infertility, the number of referrals to infertility treatment centers has also increased. Nowadays, assisted reproductive technology (ART), including in vitro fertilization (IVF), is a treatment for infertility or genetic problems. Considering the possible consequences of this method among women undergoing in vitro fertilization (IVF) and kids conceived by IVF, extensive research has been conducted in this regard.

Methods

Overall, 100 articles were entered into the study, and relevant articles were searched and extracted from PubMed, Springer, and Google Scholar databases. In IVF procedure, medications such as Clomiphene citrate and gonadotropins are used to stimulate and mature follicles and thus increase ovulation.

Results

There are conflicting opinions on this issue. Some findings report a slight increase in cancer risk for hormone-sensitive cancers including breast cancer. The long-term use of IVF medications can increase estrogen hormones and cause excessive expression of genes, resulting in an increased risk of breast cancer, which is one of the most frequent cancers among women.

Conclusion

There are some risks to be aware of, which followed the hypothesis that long IVF treatment process may lead to breast cancer among IVF candidates. Furthermore, the risk of breast cancer may be increased in those women with a positive family history and related inherited genes. Therefore, women candidates for IVF should be informed of the probable implications of the reproductive therapy techniques.

Update on the Role of Neuropeptide Y and Other Related Factors in Breast Cancer and Osteoporosis

Breast cancer and osteoporosis are common diseases that affect the survival and quality of life in postmenopausal women. Women with breast cancer are more likely to develop osteoporosis than women without breast cancer due to certain factors that can affect both diseases simultaneously. For instance, estrogen and the receptor activator of nuclear factor-κB ligand (RANKL) play important roles in the occurrence and development of these two diseases. Moreover, chemotherapy and hormone therapy administered to breast cancer patients also increase the incidence of osteoporosis, and in recent years, neuropeptide Y (NPY) has also been found to impact breast cancer and osteoporosis.Y1 and Y5 receptors are highly expressed in breast cancer, and Y1 and Y2 receptors affect osteogenic response, thus potentially highlighting a potential new direction for treatment strategies. In this paper, the relationship between breast cancer and osteoporosis, the influence of NPY on both diseases, and the recent progress in the research and treatment of these diseases are reviewed.

Barriers and facilitators to mammography among women with intellectual disabilities: a qualitative approach

Although women with intellectual disabilities have the same breast cancer incidence rate as women without intellectual disabilities, they have fewer mammograms and higher mortality rates. Qualitative inquiry was employed to explore barriers and facilitators to mammography among this population. In-depth qualitative interviews were conducted with 30 women with intellectual disabilities and their caregivers in Philadelphia during 2015-2016. Thematic analysis was conducted using inductive and deductive coding. While results provide further evidence for prior research on barriers to mammography among women with intellectual disabilities (e.g. being unprepared, fear of the exam), this study generated novel barriers such as lack of breast ultrasound awareness, sedation failing to work, and lack of mammogram education in adult day programs, and novel facilitators such as extended family support and positive attitudes. Results support the need to address barriers and promote facilitators to improve the breast cancer screening experience among women with intellectual disabilities.

Aberrant alternative splicing in breast cancer

Alternative splicing is critical for human gene expression regulation, which plays a determined role in expanding the diversity of functional proteins. Importantly, alternative splicing is a hallmark of cancer and a potential target for cancer therapeutics. Based on the statistical data, breast cancer is one of the top leading causes of cancer-related deaths in women worldwide. Strikingly, alternative splicing is closely associated with breast cancer development. Here, we seek to provide a general review of the relationship between alternative splicing and breast cancer. We introduce the process of alternative splicing and its regulatory role in cancers. In addition, we highlight the functions of aberrant alternative splicing and mutations of splicing factors in breast cancer progression. Moreover, we discuss the role of alternative splicing in cancer drug resistance and the potential of being targets for cancer therapeutics.

Morbidity Profile of Cases Attended Oncology Center of Mansoura University (OCMU), Egypt: A Cross-Sectional Study

Objectives

In Egypt, the National Cancer Registry Program integrates hospital-based data from multiple Egyptian governorates to obtain representative rates. Unfortunately, Dakahlia (one of the largest Egyptian governorates) was not integrated in the National Cancer Registry Program. This research aimed to acquire malignancy rates from the Oncology Center of Mansoura University, which is one of the two oncology centers present in Dakalia Governorate in Egypt.

Methods

Electronic records of patients who attended the Oncology Center of Mansoura University during 2016 were accessed with permission. Analysis was performed to extract diagnostic categories (age, gender, and geographic distribution of cases).

Results

Most commonly diagnosed malignancies were breast cancer which represented about 10% of cases in the Oncology Center of Mansoura University during 2016. This was followed by leukemia (3.80%), lymphoma (3.59%), and liver cancer (3.44%). Diagnoses encountered included benign and malignant tumors as well as non-tumor diagnoses. The Mansoura district had the highest proportionate rate of breast cancer cases. Females in the age group ≥ 35 < 60 years had the highest incidence of malignancy cases across all diagnoses.

Conclusion

The burden of breast cancer in Mansoura district is high. Risk factors need further evaluation with a recommendation to perform an environmental risk assessment.

Dissecting the prevention of estrogen-dependent breast carcinogenesis through Nrf2-dependent and independent mechanisms

Breast cancer is the most common malignancy among women worldwide. Various studies indicate that prolonged exposure to elevated levels of estrogens is associated with development of breast cancer. Both estrogen receptor-dependent and independent mechanisms can contribute to the carcinogenic effects of estrogens. Among them, the oxidative metabolism of estrogens plays a key role in the initiation of estradiol-induced breast cancer by generation of reactive estrogen quinones as well as the associated formation of oxygen free radicals. These genotoxic metabolites can react with DNA to form unstable DNA adducts which generate mutations leading to the initiation of breast cancer. A variety of endogenous and exogenous factors can alter estrogen homeostasis and generate genotoxic metabolites. The use of specific phytochemicals and dietary supplements can inhibit the risk of breast cancer not only by the modulation of several estrogen-activating enzymes (CYP19, CYP1B1) but also through the induction of various cytoprotective enzymes (eg, SOD3, NQO1, glutathione S-transferases, OGG-1, catechol-O-methyltransferases, CYP1B1A, etc.) that reestablish the homeostatic balance of estrogen metabolism via nuclear factor erythroid 2-related factor 2 (Nrf2)-dependent and independent mechanisms.

Risk factors for Luminal A ductal carcinoma in situ (DCIS) and invasive breast cancer in the Carolina Breast Cancer Study

Purpose

Invasive breast cancers are thought to arise from in situ lesions, but some ductal carcinoma in situ (DCIS) are indolent with low likelihood of progressing to invasive carcinoma. Comparison of risk factor associations between DCIS and invasive disease may elucidate which factors influence early versus late stages of carcinogenesis. Therefore, we determined whether there were differences in risk factor profiles for screen-detected DCIS and invasive breast cancer among Luminal A lesions.

Methods

We conducted a case-control analysis using data from the Carolina Breast Cancer Study (1993–2001). Analyses were restricted to Luminal A tumors and screen-detected tumors among mammography-eligible women, to limit confounding by mode of detection (N = 108 DCIS; N = 203 invasive). Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for associations between risk factors and lesion type.

Results

In stratified analyses, we observed qualitative differences in the direction of association for ever smoking, obese BMI, high waist-to-hip-ratio (WHR), and ≥10 years of oral contraceptive use between DCIS and invasive disease. Breastfeeding was inversely associated with invasive disease and was not associated with DCIS. Interaction tests for risk factor associations between Luminal A DCIS and invasive breast cancer were not statistically significant (p>0.05).

Conclusions

Among Luminal A tumors, established breast cancer risk factors may exert stronger effects on progression of early lesions to invasive disease, with lesser effects on risk of DCIS.

Risk-Reducing Options for Women with a Hereditary Breast Cancer Predisposition

Genetic testing is now widely utilized to identify women with a hereditary predisposition for breast cancer. Women who carry mutations that increase breast cancer risk may consider three options to reduce risk: screening, chemoprevention, and prophylactic surgery. Yet, no randomized trials have specifically assessed the efficacy of these options in mutation carriers. In many developed countries, mammography is regarded as the optimal means of screening for breast cancer in the general population. However, breast MRI is a more sensitive screening tool, and for mutation carriers, any breast cancer screening strategy should incorporate screening with MRI. In randomized trials of women at high risk for developing breast cancer, chemoprevention reduces that risk, but it has not been shown to reduce mortality. Finally, observational studies suggest that, in mutation carriers, prophylactic surgery may reduce the risk of developing breast cancer by 90-95%. There are several prophylactic mastectomy procedures to choose from, and these are generally done in conjunction with breast reconstruction. In this article, we discuss management of women who carry mutations that have been associated with an increased breast cancer risk. Mutation carriers should be informed of the potential risks and benefits of the three available options to reduce breast cancer risk.

Expression of androgen receptor in invasive ductal breast carcinomas: a clinicopathological study from Jordan

BACKGROUND

The clinical relevance of androgen receptors (ARs) expressed in breast cancer cells and the suggested prognostic impact has been an area of active research. The prevalence rate of AR expression in breast cancer has never been reported among Jordanian patients.

OBJECTIVE

Determine the expression rate of ARs among invasive ductal breast cancer cases of different stages and molecular subtypes. Also, analyze the relationship between AR expression and clinicopathologic and immunohistochemical criteria, and assess the impact of AR expression on survival.

DESIGN

Retrospective medical record review.

SETTING

Tertiary care hospital in Amman, Jordan.

PATIENTS AND METHODS

Our study comprised only of cases of invasive ductal breast carcinoma of no special type among females from records during a 10-year period between 2006 and 2015. Immunohistochemical staining was considered positive if more than 10% of tumor nuclei showed positive staining.

MAIN OUTCOME MEASURES

The expression rate of ARs and the association of the expression rate with the clinicopathologic features of invasive breast cancer.

SAMPLE SIZE

293.

RESULTS

Immunohistochemical staining for AR revealed positive stain.ing in 180 (61.4%) cases, including approximately 50% of triple-negative breast cancer cases. AR positivity correlated with estrogen receptor (ER) status (P=.007) and smaller T size (P=.014). However, no significant association was found with any of the other variables. AR expression was positively associated with overall survival (P=.022) in general and in ER-positive cases (P=.012). However, in the multivariate Cox regression model, AR was not independently associated with survival.

CONCLUSIONS

These results were consistent with international reports showing a significant relationship of AR expression with ER status. In addition, AR expression was significantly associated with smaller tumor size. Although AR status was not independently associated with survival, our data suggest AR is a good prognostic factor.

LIMITATIONS

Some clinical data were missing.

CONFLICT OF INTEREST

None.

Risk of breast cancer in the UK biobank female cohort and its relationship to anthropometric and reproductive factors

BACKGROUND

Anthropometric and reproductive factors have been reported as being established risk factors for breast cancer (BC). This study explores the contribution of anthropometric and reproductive factors in UK females developing BC in a large longitudinal cohort.

METHODS

Data from the UK Biobank prospective study of 273,467 UK females were analyzed. Relative risks (RRs) and 95% confidence intervals (CIs) for each factor were adjusted for age, family history of BC and deprivation score. The analyses were stratified by the menopausal status.

RESULTS

Over the 9 years of follow up the total number of BC cases were 14,231 with 3,378 (23.7%) incident cases with an incidence rate of 2.09 per 1000 person-years. In pre-menopausal, increase in age, height, having low BMI, low waist to hip ratio, first degree family history of BC, early menarche age, nulliparous, late age at first live birth, high reproductive interval index, and long contraceptive use duration were all significantly associated with an increased BC risk. In post-menopausal, getting older, being taller, having high BMI, first degree BC family history, nulliparous, late age at first live birth, and high reproductive interval index were all significantly associated with an increased risk of BC. The population attributable fraction (PAF) suggested that an early first live birth, lower reproductive interval index and increased number of children can contribute to BC risk reduction up to 50%.

CONCLUSIONS

This study utilizes the UK Biobank study to confirm associations between anthropometric and reproductive factors and the risk of breast cancer development. Result of attributable fraction of risk contributed by each risk factor suggested that lifetime risk of BC can be reduced by controlling weight, reassessing individual approaches to the timing of childbirth and options for contraception and considering early screening for women with family history in the first degree relative.

Significant Association of the MDM2 T309G Polymorphism with Breast Cancer Risk in a Turkish Population

Background:

Breast cancer is a leading cause of death in women worldwide. Genetic polymorphisms have been reported to be important etiological factors. Murine double minute 2 (MDM2) T309G interacts with p53 and mutations in p53 are present in approximately 50% of all cancers. However, it has been reported that effect of the polymorphism on breast cancer risk may vary in different populations. Here, we therefore investigated whether there is an association between MDM2 T309G (rs2279744) polymorphism and breast cancer in a Turkish population.

Materials and Methods:

We analysed 110 patients with breast cancer and 138 matched? controls. For genotyping, polymerase chain reaction and restriction length fragment polymorphism methods were used.

Results:

A significant difference was observed between case and control groups with regard to the distribution of the MDM2 T309G polymorphism (p<0.05). There was a significantly higher frequency of the TT genotype in the control group (p=0.028; OR, 2.42; 95% CI, 1.09-5.37). However, we did not find any relationships among tumor grade and metastasis status and this polymorphism.

Conclusion:

This study indicates that the MDM2 T309G polymorphism GG genotype and the TG+GG combination may be risk factors for breast cancer in our Turkish population.

An estrogen-related lifestyle score is associated with risk of postmenopausal breast cancer in the PLCO cohort

PURPOSE

Healthy or unhealthy lifestyle behaviors are often adopted together. We aimed to investigate the combined effect of estrogen-related lifestyle factors on postmenopausal breast cancer risk.

METHODS

Data from 27,153 women enrolled in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial were used. We created an estrogen-related lifestyle score (ERLS) by incorporating a previously developed measure of estrogenic diet, alcohol intake, body mass index (BMI), and physical activity. The scores ranged from 0 to 6 with alcohol and BMI accounting for higher weights than the other factors. To evaluate the preventive possibilities of a low estrogen-related lifestyle and to be consistent with other published lifestyle scores, higher scores were set to correspond with potentially lower estrogenic lifestyle. The association between the ERLS and incident breast cancer was examined using Cox proportional hazards models.

RESULTS

Participants with an ERLS of 4 or ≥ 5 had a 23% (HR 0.77; 95% CI 0.67-0.89) and 34% (HR 0.66; 95% CI 0.56-0.78) lower risk of breast cancer, respectively, compared to those with an ERLS ≤ 2 after multivariable adjustment. Estimates were similar when restricting to invasive cases or estrogen receptor-positive subtypes. No single lifestyle component appeared to drive the association.

CONCLUSIONS

Our findings suggest that the combined effect of a lifestyle characterized by a low estrogenic diet, low alcohol consumption, low body weight, and high levels of physical activity are associated with a reduction in postmenopausal breast cancer risk, possibly through an influence on estrogen metabolism.

A dietary pattern based on estrogen metabolism is associated with breast cancer risk in a prospective cohort of postmenopausal women

Increased exposure to estrogen is a risk factor for postmenopausal breast cancer, and dietary factors can influence estrogen metabolism. However, studies of diet and breast cancer have been inconclusive. We developed a dietary pattern associated with levels of unconjugated estradiol and the ratio of 2- and 16-hydroxylated estrogen metabolites in a subsample of Prostate, Lung, Colorectal and Ovarian Screening Trial (PLCO) participants (n = 653) using reduced rank regression, and examined its association with postmenopausal breast cancer prospectively in the larger PLCO cohort (n = 27,488). The estrogen-related dietary pattern (ERDP) was comprised of foods with positively-weighted intakes (non-whole/refined grains, tomatoes, cruciferous vegetables, cheese, fish/shellfish high in ω-3 fatty acids, franks/luncheon meats) and negatively-weighted intakes (nuts/seeds, other vegetables, fish/shellfish low in ω-3 fatty acids, yogurt, coffee). A 1-unit increase in the ERDP score was associated with an increase in total (HR: 1.09, 95% CI: 1.01-1.18), invasive (HR: 1.13; 95% CI: 1.04-1.24) and estrogen receptor (ER)-positive (HR: 1.13, 95% CI: 1.02-1.24) breast cancer risk after adjustment for confounders. Associations were observed for the fourth quartile of ERDP compared with the first quartile for overall breast cancer (HR: 1.14; 95% CI: 0.98-1.32), invasive cases (HR: 1.20, 95% CI: 1.02-1.42) and ER-positive cases (HR: 1.19; 95% CI: 0.99-1.41). The increased risk associated with increasing ERDP score was more apparent in strata of some effect modifiers (postmenopausal hormone therapy non-users and non-obese participants) where the relative estrogen exposure due to that factor was lowest, although the p values for interaction were not statistically significant. Results suggest a dietary pattern based on estrogen metabolism is positively associated with postmenopausal breast cancer risk, possibly through an estrogenic influence.

17β-estradiol regulates the malignancy of cancer stem-like cells derived from the MCF7 cell line partially through Sox2

As a major common malignant tumor in women, the malignant behavior of breast cancer, which includes tumorigenesis and metastasis, is associated with estrogen, particularly 17β-estradiol (E2). With accumulating evidence demonstrating that cancer stem-like cells (CSCs) serve a function in the malignant behavior of breast cancer, including metastasis, recurrence and chemoresistance, the effects of E2 on the physiological processes of CSCs have been attracting more attention. In the present study, in order to investigate the effects of E2 on CSCs, CSCs from the MCF7 breast cancer cell line were isolated and treated with 1, 10 and 50 nM E2. Detection of cell proliferation following E2 treatment revealed that 10 nM E2 treatment inhibited cell proliferation, whereas 50 nM E2 treatment resulted in the induction of apoptosis on CSCs. In order to further investigate the effects of E2 treatment on migration, colony formation and the self-renewal capacity of CSCs in vitro, cells were treated with 1 and 10 nM E2. As expected, compared with mock group, the self-renewal capacity of the CSCs was slightly increased by 10 nM E2 treatment, while 1 nM exhibited no observable effect. E2 treatment demonstrated different effects on the proliferation, migration, colony formation and self-renewal capacity of CSCs in a dose-dependent manner.

Almost Complete Lack of Human Cytomegalovirus and Human papillomaviruses Genome in Benign and Malignant Breast Lesions in Shiraz, Southwest of Iran

Breast cancer ranks as the most common cancer among women worldwide. There have been controversial reports regarding contributions of human papillomaviruses (HPVs) and human cytomegalovirus (HCMV) to its development. The aim of this study was to determine the frequency of HPV and HCMV positivity in benign and malignant breast tumors.

Role of MicroRNA Regulation in Obesity-Associated Breast Cancer: Nutritional Perspectives

Breast cancer is the most common malignancy diagnosed in women, and the incidence of breast cancer is increasing every year. Obesity has been identified as one of the major risk factors for breast cancer progression. The mechanisms by which obesity contributes to breast cancer development is not yet understood; however, there are a few mechanisms counted as potential producers of breast cancer in obesity, including insulin resistance, chronic inflammation and inflammatory cytokines, adipokines, and sex hormones. Recent emerging evidence suggests that alterations in microRNA (miRNA) expressions are found in several diseases, including breast cancer and obesity; however, miRNA roles in obesity-linked breast cancer are beginning to unravel. miRNAs are thought to be potential noninvasive biomarkers for diagnosis and prognosis of cancer patients with comorbid conditions of obesity as well as therapeutic targets. Recent studies have evidenced that nutrients and other dietary factors protect against cancer and obesity through modulation of miRNA expressions. Herein, we summarize a comprehensive overview of up-to-date information related to miRNAs and their molecular targets involved in obesity-associated breast cancer. We also address the mechanisms by which dietary factors modulate miRNA expression and its protective roles in obesity-associated breast cancer. It is hoped that this review would provide new therapeutic strategies for the treatment of obesity-associated breast cancer to reduce the burden of breast cancer.

Association of striking life events with primary breast cancer in 265 Chinese women: a case-control study

The current case-control study investigated the relationship between striking life events and breast cancer in Chinese women. A total of 265 primary breast cancer patients and 265 controls were enrolled with matching for age and completed questionnaires. Logistic regression analysis was used. Thirty-nine breast cancer patients reported striking life events and twenty-four of the controls reported striking life events. The number of striking life events was significantly greater in patients (p = 0.04). It indicated a striking life event led to a 1.726-fold increased HR (95% CI 1.005-2.965, p < 0.05) for breast cancer with adjustment for age, and a 1.811-fold increased HR (95% CI 1.021 - 3.212, P < 0.05) with adjustment for age, BMI, and late age at menopause. High BMI (OR: 1.680, 95% CI: 1.258-2.196, p < 0.05) and a family history of breast cancer (OR: 2.244, 95% CI: 1.065-4.729, p < 0.05, respectively) increased the risk of breast cancer, and late age at menopause decreased the risk for breast cancer (OR: 0.513, 95% CI: 0.303-0.868, p < 0.05). Our findings indicate a significant association between striking life events and breast cancer in Chinese women, especially in the subpopulation with high BMI or family history of breast cancer.

The health of Romanian Gypsy women in Serbia

Indigenous people are over-represented among the world's disadvantaged; their health is influenced by lack of access to critical resources including health care and by their cultural practices. We report on the health and the health practices of one group of indigenous women, the Roma/Gypsies of northern Serbia who live in poverty, reside in sub-standardized housing in segregated communities, and are poorly educated and stigmatized. We describe the environment in which they live, their health history, and the cultural practices that influence their health and health behaviors, including their sporadic utilization of health services that are provided by the state. We also present evidence supporting that, in the face of adversity, cultural practices, including those related to kinship and social support, can have significant benefits in shaping health status.

Do Breast Cancer Risk Factors Affect the Survival of Breast Cancer Patients in Southern Sri Lanka?

Background:

Breast cancer continues to be a major cause of morbidity among women in Sri Lanka. Possible effects of etiological risk factors on breast cancer specific survival (BCSS) of the disease is not clear. This study was designed to explore the impact of breast cancer risk factors on the BCSS of patients in Southern Sri Lanka.

Method:

This retro-prospective study included all breast cancer patients who had sought immunohistochemistry services at our unit from May 2006 to December 2012. A pre-tested, interviewer-administered questionnaire was used to gather information on risk factors. BCSS was estimated using the Kaplan-Meier model. Univariate Cox-regression analysis was performed with 95% confidence intervals using the SPSS statistical package.

Results:

A total of 944 breast cancer patients were included. Five year BCSS was 78.8%. There was a statistically significant difference between the patients who had a family history of breast cancer and no family history of any cancer in terms of the presence/absence of lymph node metastasis (p=0.011) and pathological stage (p=0.042). The majority of the premenopausal patients had associated DCIS (p<0.001) and large tumours (p=0.015) with positive lymph nodes (p=0.016). There was no statistically significant association between hormone receptor subtypes and hormone related risk factors. Univariate analysis revealed that breast cancer risk factors had no significant effect on the BCSS.

Conclusion:

Even though family history of breast cancer and premenopausal status are associated with poor prognostic features, they, in line with the other breast cancer risk factors, appear to have no significant effect on the BCSS of patients in Southern Sri Lanka.

Recent perspectives of breast cancer prognosis and predictive factors

Breast cancer is the most common type of cancer affecting women worldwide. Although there have been great improvements in treating the disease and at present between 80 and 90% of the women survive ≥5-years after their primary diagnosis. However, due to the high incidence of the disease >450,000 women succumb to breast cancer annually worldwide. The majority of improvements in breast cancer survival may be explained through better knowledge of the development and progression of the disease. Consequently, the treatments employed have become more effective. Furthermore, continuous efforts are being made for the identification of novel and efficient biomarkers for the timely prognosis of breast cancer. The present review aims to examine recent perspectives of breast cancer prognosis and the predictive factors involved.

The influence of personality and perceived stress on the development of breast cancer: 20-year follow-up of 29,098 Japanese women

Breast cancer is the most common cancer in women. However, it remains unproven whether psychological factors have an influence on breast cancer incidence. In our earlier study, subjects possessing two personality traits, decisiveness and "ikigai" (a Japanese word meaning something that makes one's life worth living), showed a significantly lower risk of developing breast cancer, although no psychological factors have been convincingly demonstrated to have an influence on breast cancer development in other studies. Therefore, we conducted this follow-up analysis to confirm the association between breast cancer incidence and psychological traits, using the final dataset of a large-scale prospective cohort study in Japan. We identified 209 cases of incident breast cancer out of a maximum 21-year follow-up of 29,098 Japanese women. Cox proportional hazard regression analysis, adjusted for the same potential confounders used in our previous study, did not reveal any significant relationships between breast cancer incidence and four psychological traits: having "ikigai", decisiveness, ease of anger arousal, and perceived stress. Our finding is consistent with previous studies, and suggests that the psychological traits are unlikely to be an important risk factor for breast cancer.

Descriptive epidemiology of breast cancer in China: incidence, mortality, survival and prevalence

Breast cancer is the most common neoplasm diagnosed amongst women worldwide and is the leading cause of female cancer death. However, breast cancer in China is not comprehensively understood compared with Westernised countries, although the 5-year prevalence statistics indicate that approximately 11 % of worldwide breast cancer occurs in China and that the incidence has increased rapidly in recent decades. This paper reviews the descriptive epidemiology of Chinese breast cancer in terms of incidence, mortality, survival and prevalence, and explores relevant factors such as age of manifestation and geographic locations. The statistics are compared with data from the Westernised world with particular emphasis on the United States and Australia. Potential causal agents responsible for differences in breast cancer epidemiology between Chinese and other populations are also explored. The need to minimise variability and discrepancies in methods of data acquisition, analysis and presentation is highlighted.

Passive Smoking and Breast Cancer - a Suspicious Link

BACKGROUND

Breast cancer is the most common malignancy of women in the world. The disease is caused by infectious and non-infectious, environmental and lifestyle factors. Tobacco smoke has been one of the most widely studied environmental factors with possible relevance to breast cancer. The purpose of this study was to assess the impact of tobacco smoking in breast cancer patients in a hospital based cohort and to establish prognostic implications if any.

MATERIALS AND METHODS

A retrospective audit of 100 women with pathological diagnosis of invasive breast cancer was included in this study. The verbal questionnaire elicited information on current and previous history of exposure to smoking in addition to active smoking. All analyses were adjusted for potential confounders, including stage at presentation, alcohol intake, hormonal replacement therapy, oral contraceptive intake, obesity and menopausal status.

RESULTS

The mean age at presentation of breast cancer was 51.4 ± 10.86 years. Mean age of presentation was 53.1±11.5 and 45.7±11.9 years in never smokers and passive smokers, respectively. Age at presentation varied widely in patients exposed to tobacco smoke for >10 years in childhood from 40.3± 12.0 years to 47.7± 13.9 in patients exposed for > 20 years as adults. Among passive smokers, 60.9% were premenopausal and 39.1% of patients were postmenopausal. In never smokers, 71.4% were post menopausal. Expression of receptors in non-smokers vs passive smokers was comparable with no significant differences. Metastatic potential in lung parenchyma was slightly elevated in passive smokers as compared to never smokers although statistically non-significant.

CONCLUSIONS

An inverse relationship exists between the intensity and duration of smoking and the age at presentation and poor prognostic factors. The results strongly suggest efforts should be taken to prevent smoking, encourage quitting and restrict exposure to second hand smoke in India.

Separation, characterization and anticancer activities of a sulfated polysaccharide from Undaria pinnatifida

The purpose of this paper was to investigate separation, characterization and anticancer activities of a sulfated polysaccharide (SPUP) from Undaria pinnatifida. Firstly, polysaccharide from U. pinnatifida was separated by DEAE-52 cellulose and Sephacryl S-400 column chromatography. As results, SPUP was obtained with the yield of 19.42%. Then, SPUP was characterized using chemical analysis, gas chromatography, size-exclusion HPLC chromatography, UV-vis spectra and FT-IR spectrum. The content of total sugar, uronic acid, protein and sulfate radical were 80.48%, 3.21%, 7.12% and 29.14%, respectively. SPUP was a heteropolysaccharide composed of fucose, glucose and galactose in a molar percentage of 27.15:19.34:53.51 with molecular weight of 97.9 kDa. Finally, the strongly against breast cancer activity of SPUP was confirmed by DMBA-induced breast cancer rats model. AS results, SPUP can significantly restrain breast abnormal enlargement, prolong tumor latency and reduced tumor incidence. Immunomodulatory activity and regulating abnormal sex hormones level might contribute to its anticancer activities.

Urban Endocrine Disruptors Targeting Breast Cancer Proteins

Humans are exposed to a huge amount of environmental pollutants called endocrine disrupting chemicals (EDCs). These molecules interfere with the homeostasis of the body, usually through mimicking natural hormones leading to activation or blocking of their receptors. Many of these compounds have been associated with a broad range of diseases including the development or increased susceptibility to breast cancer, the most prevalent cancer in women worldwide, according to the World Health Organization. Thus, this article presents a virtual high-throughput screening (vHTS) to evaluate the affinity of proteins related to breast cancer, such as ESR1, ERBB2, PGR, BCRA1, and SHBG, among others, with EDCs from urban sources. A blind docking strategy was employed to screen each protein-ligand pair in triplicate in AutoDock Vina 2.0, using the computed binding affinities as ranking criteria. The three-dimensional structures were previously obtained from EDCs DataBank and Protein Data Bank, prepared and optimized by SYBYL X-2.0. Some of the chemicals that exhibited the best affinity scores for breast cancer proteins in each category were 1,3,7,8-tetrachlorodibenzo-p-dioxin, bisphenol A derivatives, perfluorooctanesulfonic acid, and benzo(a)pyrene, for catalase, several proteins, sex hormone-binding globulin, and cytochrome P450 1A2, respectively. An experimental validation of this approach was performed with a complex that gave a moderate binding affinity in silico, the sex hormone binding globulin (SHBG), and bisphenol A (BPA) complex. The protein was obtained using DNA recombinant technology and the physical interaction with BPA assessed through spectroscopic techniques. BPA binds on the recombinant SHBG, and this results in an increase of its α helix content. In short, this work shows the potential of several EDCs to bind breast cancer associated proteins as a tool to prioritize compounds to perform in vitro analysis to benefit the regulation or exposure prevention by the general population.

Insulin priming effect on estradiol-induced breast cancer metabolism and growth

Diabetes is a risk factor for breast cancer development and is associated with poor prognosis for breast cancer patients. However, the molecular and biochemical mechanisms underlying the association between diabetes and breast cancer have not been fully elucidated. Here, we investigated estradiol response in MCF-7 breast cancer cells with or without chronic exposure to insulin. We found that insulin priming is necessary and specific for estradiol-induced cancer cell growth, and induces anaplerotic shunting of glucose into macromolecule biosynthesis in the estradiol treated cells. Treatment with ERK or Akt specific inhibitors, U0126 or LY294002, respectively, suppressed estradiol-induced growth. Interestingly, molecular analysis revealed that estradiol treatment markedly increases expression of cyclin A and B, and decreases p21 and p27 in the insulin-primed cells. In addition, estradiol treatment activated metabolic genes in pentose phosphate (PPP) and serine biosynthesis pathways in the insulin-primed cells while insulin priming decreased metabolic gene expression associated with glucose catabolism in the breast cancer cells. Finally, we found that anti-diabetic drug metformin and AMPK ligand AICAR, but not thiazolidinediones (TZDs), specifically suppress the estradiol-induced cellular growth in the insulin-primed cells. These findings suggest that estrogen receptor (ER) activation under chronic hyperinsulinemic condition increases breast cancer growth through the modulation of cell cycle and apoptotic factors and nutrient metabolism, and further provide a mechanistic evidence for the clinical benefit of metformin use for ER-positive breast cancer patients with diabetes.

Association Between Leptin (-2548G/A) Genes Polymorphism and Breast Cancer Susceptibility: A Meta-Analysis

Leptin is a confirmed breast cancer susceptibility gene. However, published studies reported mixed results. This meta-analysis was conducted to systematically get a more accurate estimation of the association between the Leptin (-2548G/A) gene polymorphism and breast cancer risk. To assess the effect of Leptin (-2548G/A) gene polymorphism on breast cancer susceptibility, we searched PUBMED, ISI Web of Knowledge, EMBASE, Chinese National Knowledge Infrastructure (CNKI) databases until September 2015 to identify eligible studies, without restriction. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the susceptibility to breast cancer. Separate analyses were conducted on features of the population such as ethnicity, source of controls, and country. A total of 9 case-control studies on Leptin (-2548G/A) gene polymorphism and breast cancer risk, including 3725 cases and 3093 case-free controls were identified. The results revealed that compared with the G allele, the A allele was associated with modestly increased risk of overall breast cancer (A vs G: OR = 1.12, 95%CI = 1.04-1.20, P = 0.002, Phet P < 0.00001). Following further stratified analyses, in the subgroup analyses by ethnicity, a significantly increased risk was observed among Caucasian (A vs G: OR = 1.11, 95%CI = 1.03-1.20, P = 0.006, Phet = 0.00001). No publication bias was found in the present study. In conclusion, our meta-analysis suggests that the Leptin (-2548G/A) gene polymorphism plays an important role in breast cancer susceptibility, especially in Caucasian.

Ramalin-Mediated Apoptosis Is Enhanced by Autophagy Inhibition in Human Breast Cancer Cells

Breast cancer, the most commonly diagnosed cancer in women worldwide, is treated in various ways. Ramalin is a chemical compound derived from the Antarctic lichen Ramalina terebrata and is known to exhibit antioxidant and antiinflammatory activities. However, its effect on breast cancer cells remains unknown. We examined the ability of ramalin to induce apoptosis and its mechanisms in MCF-7 and MDA-MB-231 human breast cancer cell lines. Ramalin inhibited cell growth and induced apoptosis in both cell lines in a concentration-dependent manner. By upregulating Bax and downregulating Bcl-2, ramalin caused cytochrome c and apoptosis-inducing factor to be released from the mitochondria into the cytosol, thus activating the mitochondrial apoptotic pathway. In addition, activated caspase-8 and caspase-9 were detected in both types of cells exposed to ramalin, whereas ramalin activated caspase-3 only in the MDA-MB-231 cells. Ramalin treatment also increased the levels of LC3-II and p62. Moreover, the inhibition of autophagy by 3-methyladenine or Atg5 siRNA significantly enhanced ramalin-induced apoptosis, which was accompanied by a decrease in Bcl-2 levels and an increase in Bax levels. Therefore, autophagy appears to be activated as a protective mechanism against apoptosis in cancer cells exposed to ramalin. These findings suggest that ramalin is a potential anticancer agent for the treatment of patients with non-invasive or invasive breast cancer.

Methylsulfonylmethane inhibits HER2 expression through STAT5b in breast cancer cells

Breast cancer is the most common cancer in women globally. The factors that increase risk include: late age at first birth, alcohol, radiation exposure, family history of breast cancer, and postmenopausal hormone therapy. Numerous drugs are being developed to treat breast cancer. Among them, Herceptin is used for the treatment of human epidermal growth factor receptor 2 (HER2)-positive cases and targets HER2 effectively and efficiently, but it is very expensive. Methylsulfonylmethane (MSM) is an organic sulfur-containing natural compound having no reported toxicity. We examined MSM in breast cancer cell lines and found it inhibited the proliferation of estrogen receptor-positive and HER2-positive breast cancer cells in a dose-dependent manner. It also suppressed the activation of STAT5b and expression of HER2 in breast cancer cells. We determined the STAT5b binding site (GAS element) in the HER2 gene. Detailed analysis showed that MSM decreased the ability of STAT5b to bind the promoter of the HER2 gene and a luciferase assay demonstrated reduced activity. We confirmed that MSM can effectively regulate STAT5b, and thereby decrease HER2 expression. Therefore, we recommend the use of MSM as an inhibitor for the management of HER2-positive breast cancers.

Familial clustering of breast and prostate cancer and risk of postmenopausal breast cancer in the Women's Health Initiative Study

BACKGROUND

Evidence suggests that the risk of breast and prostate cancer is increased among those with a family history of the same disease and particularly among first-degree relatives. However, less is known about the relationship between breast and prostate cancer within families and particularly among minority populations.

METHODS

Analyses of participants in the Women's Health Initiative observational cohort who were free of breast cancer at the time of their baseline examination were conducted. Subjects were followed for breast cancer through August 31, 2009. A Cox proportional hazards regression modeling approach was used to estimate the risk of breast cancer associated with a family history of prostate cancer, breast cancer, and both among first-degree relatives.

RESULTS

There were 78,171 eligible participants, and 3506 breast cancer cases were diagnosed during the study period. A family history of prostate cancer was associated with a modest increase in breast cancer risk after adjustments for confounders (adjusted hazard ratio [aHR], 1.14; 95% confidence interval [CI], 1.02-1.26). In a separate analysis examining the joint impact of both cancers, a family history of both breast and prostate cancer was associated with a 78% increase in breast cancer risk (aHR, 1.78; 95% CI, 1.45-2.19). Risk estimates associated with a family history of both breast and prostate cancer were higher among African American women (aHR, 2.34; 95% CI, 1.09-5.02) versus white women (aHR, 1.66; 95% CI, 1.33-2.08).

CONCLUSIONS

These findings suggest that prostate cancer diagnosed among first-degree family members increases a woman's risk of developing breast cancer. Future studies are needed to determine the relative contributions of genes and a shared environment to the risk for both cancers.

Lack of association between the matrix metalloproteinase-2 -1306C>T polymorphism and breast cancer susceptibility: a meta-analysis

BACKGROUND

Since inconsistent results have been reported regarding the relation between the matrix metalloproteinase-2 (MMP-2) -1306C>T polymorphism and susceptibility for breast cancer, we performed a meta-analysis to investigate the issue.

MATERIALS AND METHODS

An internet search of PubMed and EMBASE was performed to identify eligible studies. Pooled odds ratios (ORs) with their corresponding confidence intervals (CIs) were calculated to evaluate any association between MMP-2 -1306C>T polymorphism and breast cancer susceptibility.

RESULTS

Nine case-control studies were included in the meta-analysis, involving 9,858 cases and 10,871 controls. Overall, there was no evidence of any association between the MMP-2 -1306C>T polymorphism and breast cancer susceptibility in different genetic models (T-allele vs C-allele: OR=0.95, 95%CI, 0.82-1.10, p=0.49; TT vs CC: OR=1.03, 95%CI, 0.90-1.19, p=0.66; TT+TC vs CC: OR=0.93, 95%CI, 0.78-1.10, p=0.38; TT vs TC+CC: OR=1.02, 95%CI, 0.89-1.17, p=0.77). In the subgroup analysis by ethnicity, CC was associated with a significant increase in breast susceptibility among Latin-Americans in the dominant model (OR=0.61, 95%CI, 0.40-0.93, p=0.02), but the association disappeared in other models. No significant association was observed among Europeans, East Asians and others in different genetic models. In the subgroup analysis by their source of controls, no significant association between MMP-2 -1306C>T polymorphism and breast cancer susceptibility was noted among population-based studies and hospital-based studies in different genetic models.

CONCLUSIONS

The results of this meta-analysis suggest that MMP-2 -1306C>T polymorphism is not associated with breast cancer susceptibility, although the association among Latin-Americans in the dominant model was significant.

Dose-dependent effects of isoflavone exposure during early lifetime on the rat mammary gland: Studies on estrogen sensitivity, isoflavone metabolism, and DNA methylation

SCOPE

Isoflavone (ISO) exposure during adolescence modulates 17β-estradiol (E2) sensitivity of the adult mammary gland. The present study investigated the dose dependency of these effects focusing on proliferation, estrogen receptor dependent and independent gene expression, as well as DNA methylation and ISO metabolism.

METHODS AND RESULTS

Female Wistar rats were lifelong exposed to an ISO-depleted diet or to diets enriched with a soy ISO extract (ISO-rich diet (IRD)) causing plasma concentrations as observed minimally (IRDlow) and maximally (IRDhigh) in Asian women. The extract was characterized by both phytochemical analysis and E-Screen. Rats were ovariectomized at postnatal day (PND) 80 and treated with E2 from PND94 to 97. In contrast to uterine response, body weight and visceral fat mass were affected by ISO. In the mammary gland, both E2-induced proliferation (proliferating cell nuclear antigen staining) and estrogen receptor activation (progesterone receptor staining) were significantly reduced by IRDhigh but not by IRDlow, which however attenuated Gdf15 mRNA expression. DNA methylation analysis revealed significant differences in the promoter regions of Aldhl1, Extl1, and WAP between IRDhigh and ISO-depleted diet.

CONCLUSION

Lifelong exposure to ISO results in dose-dependent differential effects on proliferation, gene expression, and DNA methylation in rat mammary glands. Yet, a decrease in estrogen responsiveness was only achieved by IRDhigh.

Induced abortion and breast cancer: results from a population-based case control study in China

AIM

To determine whether induced abortion (IA) increases breast cancer (BC) risk.

MATERIALS AND METHODS

A population-based case-control study was performed from Dec, 2000 to November, 2004 in Shanghai, China, where IA could be verified through the family planning network and client medical records. Structured questionnaires were completed by 1,517 cases with primary invasive epithelial breast cancer and 1,573 controls frequency- matched to cases for age group. The information was supplemented and verified by the family planning records. Statistical analysis was conducted with SAS 9.0.

RESULTS

After adjusting for potential confounders, induced abortions were not found to be associated with breast cancer with OR=0.94 (95%CI= 0.79-1.11). Compared to parous women without induced abortion, parous women with 3 or more times induced abortion (OR=0.66, 95%CI=0.46 to 0.95) and women with 3 or more times induced abortion after the first live birth (OR=0.66, 95%CI =0.45 to 0.97) showed a lower risk of breast cancer, after adjustment for age, level of education, annual income per capita, age at menarche, menopause, parity times, spontaneous abortion, age at first live birth, breast-feeding, oral contraceptives, hormones drug, breast disease, BMI, drinking alcohol, drinking tea, taking vitamin/calcium tablet, physical activity, vocation, history of breast cancer, eating the bean.

CONCLUSIONS

The results suggest that a history of induced abortions may not increase the risk of breast cancer.

Associations between C1772T polymorphism in hypoxia-inducible factor-1α gene and breast cancer: a meta-analysis

Background

A meta-analysis was performed to estimate the association between HIF-1α polymorphism (C1772T) and breast cancer risk.

Material/Methods

The relevant published literature was retrieved from PubMed, Web of Knowledge, and Embase. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to estimate the strength of the associations.

Results

Six case-control studies, including 2043 cases and 2146 controls were identified. Meta-analysis showed that there was no marked association between C1772T polymorphism and breast cancer risk in the overall population in the dominant model. The subgroup analysis showed an increased breast cancer risk in Asians based on homozygote comparison and the recessive model. There were no associations between C1772T polymorphism with clinicopathological parameters and habits.

Conclusions

The present meta-analysis suggests that HIF-1α C1772T polymorphism is a risk factor for susceptibility to breast cancer in Asians.

Comparison of Danish dichotomous and BI-RADS classifications of mammographic density

Background

In the Copenhagen mammography screening program from 1991 to 2001, mammographic density was classified either as fatty or mixed/dense. This dichotomous mammographic density classification system is unique internationally, and has not been validated before.

Purpose

To compare the Danish dichotomous mammographic density classification system from 1991 to 2001 with the density BI-RADS classifications, in an attempt to validate the Danish classification system.

Material and Methods

The study sample consisted of 120 mammograms taken in Copenhagen in 1991–2001, which tested false positive, and which were in 2012 re-assessed and classified according to the BI-RADS classification system. We calculated inter-rater agreement between the Danish dichotomous mammographic classification as fatty or mixed/dense and the four-level BI-RADS classification by the linear weighted Kappa statistic.

Results

Of the 120 women, 32 (26.7%) were classified as having fatty and 88 (73.3%) as mixed/dense mammographic density, according to Danish dichotomous classification. According to BI-RADS density classification, 12 (10.0%) women were classified as having predominantly fatty (BI-RADS code 1), 46 (38.3%) as having scattered fibroglandular (BI-RADS code 2), 57 (47.5%) as having heterogeneously dense (BI-RADS 3), and five (4.2%) as having extremely dense (BI-RADS code 4) mammographic density. The inter-rater variability assessed by weighted kappa statistic showed a substantial agreement (0.75).

Conclusion

The dichotomous mammographic density classification system utilized in early years of Copenhagen’s mammographic screening program (1991–2001) agreed well with the BI-RADS density classification system.

Estrogen metabolism and breast cancer

There is currently accumulating evidence that endogenous estrogens play a critical role in the development of breast cancer. Estrogens and their metabolites have been studied in both pre- and postmenopausal women with more consistent results shown in the latter population, in part because of large hormonal variations during the menstrual cycle and far fewer studies having been performed in premenopausal women. In this review we describe in detail estrogen metabolism and associated genetic variations, and provide a critical review of the current literature regarding the role of estrogens and their metabolites in breast cancer risk.

Role of adipokines and cytokines in obesity-associated breast cancer: therapeutic targets

Obesity is the cause of a large proportion of breast cancer incidences and mortality in post-menopausal women. In obese people, elevated levels of various growth factors such as insulin and insulin-like growth factors (IGFs) are found. Elevated insulin level leads to increased secretion of estrogen by binding to the circulating sex hormone binding globulin (SHBG). The increased estrogen-mediated downstream signaling favors breast carcinogenesis. Obesity leads to altered expression profiles of various adipokines and cytokines including leptin, adiponectin, IL-6, TNF-α and IL-1β. The increased levels of leptin and decreased adiponectin secretion are directly associated with breast cancer development. Increased levels of pro-inflammatory cytokines within the tumor microenvironment promote tumor development. Efficacy of available breast cancer drugs against obesity-associated breast cancer is yet to be confirmed. In this review, we will discuss different adipokine- and cytokine-mediated molecular signaling pathways involved in obesity-associated breast cancer, available therapeutic strategies and potential therapeutic targets for obesity-associated breast cancer.

Striking life events associated with primary breast cancer susceptibility in women: a meta-analysis study

Purpose

The association between striking life events, an important stress and acute anxiety disorder, and the occurrence of primary breast cancer is unclear. The current meta-analysis was designed to assess the relationship between striking life events and primary breast cancer incidence in women.

Methods

Systematic computerized searching of the PubMed, ScienceDirect, Embase, and BMJ databases with the combinations of controlled descriptors from Mesh, including breast cancer, breast tumor, cancer of breast, mammary carcinoma, life events, life change events, case–control studies, case-base studies, cohort study, and cohort analysis and identified a total of 307 papers published from January 1995 to April 2012. Following evaluation of methodological quality with the Downs & Black criteria, seven case–control or cohort studies were selected and the association between striking life events and primary breast cancer incidence in women was measured using random effect or fixed-effect odds ratios combined with 95% confidence interval.

Results

The seven studies included in the final meta-analysis included 99,807 women. A meta-analysis showed that the pooled OR for striking life events and breast cancer was 1.51 (95% CI 1.15 - 1.97, P = 0.003), indicating that women with striking life events were at 1.5-fold greater risk of developing breast cancer. The pooled OR for severe striking life events and breast cancer was 2.07 (95% CI 1.06 - 4.03), indicating that women with severe striking life events were at 2-fold greater risk of developing breast cancer.

Conclusions

The current meta-analysis showed significant evidence for a positive association between striking life events and primary breast cancer incidence in women.