Epidemiology and the causes of breast cancer

Inhibition of the thioredoxin system for radiosensitization therapy of cancer

Radiotherapy (RT) stands as a cornerstone in the clinical armamentarium against various cancers due to its proven efficacy. However, the intrinsic radiation resistance exhibited by cancer cells, coupled with the adverse effects of RT on normal tissues, often compromises its therapeutic potential and leads to unwanted side effects. This comprehensive review aims to consolidate our understanding of how radiosensitizers inhibit the thioredoxin (Trx) system in cellular contexts. Notable radiosensitizers, including gold nanoparticles (GNPs), gold triethylphosphine cyanide ([Au(SCN) (PEt3)]), auranofin, ceria nanoparticles (CONPs), curcumin and its derivatives, piperlongamide, indolequinone derivatives, micheliolide, motexafin gadolinium, and ethane selenide selenidazole derivatives (SeDs), are meticulously elucidated in terms of their applications in radiotherapy. In this review, the sensitization mechanisms and the current research progress of these radiosensitizers are discussed in detail, with the overall aim of providing valuable insights for the judicious application of Trx system inhibitors in the field of cancer radiosensitization therapy.

Association of vitamin D receptor gene polymorphisms with breast cancer risk

BACKGROUND

Recent literature suggests that vitamin D signaling has a protective effect against breast cancer risk. Thus, the aim of the present study was to find the association of vitamin D receptor (VDR) gene polymorphisms with breast cancer risk.

MATERIALS AND METHODS

Fok1, Bsm1, Apa1, and Taq1 polymorphisms were performed by polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) method, and Poly A polymorphism was carried out using PCR-SSCP in 140 breast cancer patients and 155 controls.

RESULTS

Odds ratio was significantly higher in both homozygous variant genotypes (LL) of Poly A polymorphism of VDR (odds ratio [OR] = 5.42, 95% confidence interval [CI] = 1.19-23.31, P = 0.02) and heterozygous variant genotypes (SL) of Poly A polymorphism of VDR (OR = 3.89, 95% CI = 1.10-13.7, P = 0.03). Fok1, Bsm1, Apa1, and Taq1 polymorphisms of VDR gene were not significantly associated with breast cancer risk.

CONCLUSION

Poly A polymorphism at the 3' untranslated region (UTR) of VDR gene was significantly associated with breast cancer risk in West Indian population.

Dietary Trace Element Intake and Risk of Breast Cancer: A Mini Review

Trace elements are essentially required for various physiological and metabolic functions, and any disturbance in the trace elements homeostasis may result in the development of chronic diseases including breast cancer. Breast cancer is the most prevalent cancer type reported in women equally affecting both the high-income and low-income countries. This review therefore aimed to evaluate the impact of dietary trace element intake in relation to the incidence of breast cancer. We focused on five trace elements, thus emphasizing dietary selenium, zinc, iron, copper, and cadmium intake and risk of breast cancer. A systematic approach was applied to perform this review through entering a search term in PubMed and Scopus databases. A total of 24 articles were included after meeting the inclusion and exclusion criteria. Most of the studies regarding dietary iron intake showed a detrimental effect of increased dietary heme iron on breast cancer incidence risk. In addition, there is a limited evidence of high dietary intake of selenium and zinc to reduce the risk of breast cancer. Also, a few studies showed a relationship between high cadmium consumption and risk of breast cancer. More studies related to cadmium and copper exposure are needed to confirm this relationship. As a result, the findings of this review suggested that high dietary heme iron is a potential risk factor for breast cancer.

Increased Prevalence of Breast and All-cause Cancer in Female Orthopaedic Surgeons

INTRODUCTION

Cancer is the second leading cause of death among women in the United States. Previous studies demonstrate a higher prevalence of cancer among female orthopaedic surgeons. This study aimed to provide an updated prevalence of breast and all-cause cancer among female orthopaedic surgeons using a larger and more current study population.

METHODS

We distributed surveys to female orthopaedic surgeons in national orthopaedic specialty societies. Six hundred seventy-two survey responses were collected. We calculated standardized prevalence ratios (SPRs) and 95% confidence intervals (CIs) based on gender-specific, race-specific, and age-specific cancer prevalence statistics in the US population. We compared the distribution of breast cancer risk factors with that of women in the 2018 and 2009 California Health Interview Survey.

RESULTS

Fifty-one of the 672 surveyed surgeons reported a diagnosis of invasive cancer. Twenty reported breast cancer with a prevalence higher among female orthopaedic surgeons compared with the US female population (SPR: 2.89, 95% CI: 2.16 to 3.81, P < 0.001). The breast cancer prevalence was also higher among orthopaedic surgeons compared with the US female population (SPR: 3.97, 95% CI: 2.43 to 6.14, P = 0.003).

DISCUSSION

The increased prevalence of breast and all-cause cancer among a larger and more diverse cohort of female orthopaedic surgeons confirms previous studies and provides an update regarding a concerning public health issue within this specialty.

Benzimidazoles Against Certain Breast Cancer Drug Targets: A Review

BACKGROUND

Benzimidazoles are widely used scaffolds against various types of cancer including breast cancer. To this end, anticancer agents must be developed using the knowledge of the specific targets of BC.

OBJECTIVE

In this study, we aim to review the compounds used against some of the biomolecular targets of breast cancer. To this end, we present information about the various targets, with their latest innovative studies.

CONCLUSION

Benzimidazole ring is an important building block that can target diverse cancer scenarios since it can structurally mimic biomolecules in the human body. Additionally, many studies imply the involvement of this moiety on a plethora of pathways and enzymes related to BC. Herein, our target-based collection of benzimidazole derivatives strongly suggests the utilization of benzimidazole derivatives against BC.

ROS Signaling-Mediated Novel Biological Targets: Brf1 and RNA Pol III Genes

Biomolecule metabolism produces ROS (reactive oxygen species) under physiological and pathophysiological conditions. Dietary factors (alcohol) and carcinogens (EGF, DEN, and MNNG) also induce the release of ROS. ROS often causes cell stress and tissue injury, eventually resulting in disorders or diseases of the body through different signaling pathways. Normal metabolism of protein is critically important to maintain cellular function and body health. Brf1 (transcript factor II B-related factor 1) and its target genes, RNA Pol III genes (RNA polymerase III-dependent genes), control the process of protein synthesis. Studies have demonstrated that the deregulation of Brf1 and its target genes is tightly linked to cell proliferation, cell transformation, tumor development, and human cancers, while alcohol, EGF, DEN, and MNNG are able to induce the deregulation of these genes through different signaling pathways. Therefore, it is very important to emphasize the roles of these signaling events mediating the processes of Brf1 and RNA Pol III gene transcription. In the present paper, we mainly summarize our studies on signaling events which mediate the deregulation of these genes in the past dozen years. These studies indicate that Brf1 and RNA Pol III genes are novel biological targets of ROS.

The short isoform of PRLR suppresses the pentose phosphate pathway and nucleotide synthesis through the NEK9-Hippo axis in pancreatic cancer

Prolactin binding to the prolactin receptor exerts pleiotropic biological effects in vertebrates. The prolactin receptor (PRLR) has multiple isoforms due to alternative splicing. The biological roles and related signaling of the long isoform (PRLR-LF) have been fully elucidated. However, little is known about the short isoform (PRLR-SF), particularly in cancer development and metabolic reprogramming, a core hallmark of cancer. Here, we reveal the role and underlying mechanism of PRLR-SF in pancreatic ductal adenocarcinoma (PDAC). Methods: A human PDAC tissue array was used to investigate the clinical relevance of PRLR in PDAC. The in vivo implications of PRLR-SF in PDAC were examined in a subcutaneous xenograft model and an orthotopic xenograft model. Immunohistochemistry was performed on tumor tissue obtained from genetically engineered KPC (KrasG12D/+; Trp53R172H/+; Pdx1-Cre) mice with spontaneous tumors. 13C-labeled metabolite measures, LC-MS, EdU incorporation assays and seahorse analyses were used to identify the effects of PRLR-SF on the pentose phosphate pathway and glycolysis. We identified the molecular mechanisms by immunofluorescence, coimmunoprecipitation, proximity ligation assays, chromatin immunoprecipitation and promoter luciferase activity. Public databases (TCGA, GEO and GTEx) were used to analyze the expression and survival correlations of the related genes. Results: We demonstrated that PRLR-SF is predominantly expressed in spontaneously forming pancreatic tumors of genetically engineered KPC mice and human PDAC cell lines. PRLR-SF inhibits the proliferation of PDAC cells (AsPC-1 and BxPC-3) in vitro and tumor growth in vivo. We showed that PRLR-SF reduces the expression of genes in the pentose phosphate pathway (PPP) and nucleotide biosynthesis by activating Hippo signaling. TEAD1, a downstream transcription factor of Hippo signaling, directly regulates the expression of G6PD and TKT, which are PPP rate-limiting enzymes. Moreover, NEK9 directly interacts with PRLR-SF and is the intermediator between PRLR and the Hippo pathway. The PRLR expression level is negatively correlated with overall survival and TNM stage in PDAC patients. Additionally, pregnancy and lactation increase the ratio of PRLR-SF:PRLR-LF in the pancreas of wild-type mice and subcutaneous PDAC xenograft tumors. Conclusion: Our characterization of the relationship between PRLR-SF signaling, the NEK9-Hippo pathway, PPP and nucleotide synthesis explains a mechanism for the correlation between PRLR-SF and metabolic reprogramming in PDAC progression. Strategies to alter this pathway might be developed for the treatment or prevention of pancreatic cancer.

Clinical significance of serum 25 hydroxyvitamin D in breast cancer: An Indian scenario

Recent evidences suggest a protective mechanism of vitamin D signaling against breast cancer by the autocrine/paracrine manner and may modestly reduce the risk of breast cancer. Despite lots of sunshine, vitamin D deficiency is widespread in India. Moreover, there are limited studies from Indian population regarding circulatory 25(OH) D and breast cancer risk. Thus, the aim of the present study is to investigate circulatory 25(OH) D in relation to breast cancer risk and its association with various clinico-pathological parameters from Indian population. Total 297 subjects, comprising of 157 controls and 140 breast cancer patients were enrolled for the study. Circulatory 25(OH) D was analyzed by HPLC. Statistical analysis was carried out by SPSS software version 15. Further, subjects were categorized into severe, moderate, mild vitamin D deficiency and sufficiency. The prevalence of severe and moderate 25(OH) D deficiency was higher in breast cancer patients as compared to controls. Mean values of 25(OH) D were lower in breast cancer patients as compared to controls in mild, moderate and severe deficient groups (p = 0.07, p = 0.003 and p = 0.001). Moreover, 25(OH) D was significantly lower in postmenopausal breast cancer patients as compared to premenopausal breast cancer patients, particularly in severe deficient group. The levels of 25(OH) D were lower in ER and PR negative receptor status as compared to the positive receptor in severe deficient category (p = 0.06 and p = 0.09 respectively). Whereas, the mean values of 25(OH) D were lower in HER 2 negative receptor status as compared to positive receptor status in the moderate deficient category (p = 0.09). Further, severe deficient group showed significantly lower levels of 25(OH) Din TNBC as compared to luminal A subtype (p = 0.01). Thus, Results indicate that 25(OH) D deficiency might be associated with increased risk of breast cancer. Moreover, severe 25(OH) D deficiency is associated with aggressive behavior of breast cancer.

The significance of Runx2 mediating alcohol-induced Brf1 expression and RNA Pol III gene transcription

Runx2 (Runt-related transcription factor 2) is a key transcription factor which is associated with osteoblast differentiation and expressed in ER+ (estrogen receptor positive) human breast cancer cell lines. Runx2 also participates in mammary gland development. Deregulation of RNA Pol III genes (polymerase III-dependent genes) is tightly linked to tumor development, while Brf1 (TFIIB-related factor 1) specifically regulates these gene transcription. However, nothing is known about the effect of Runx2 on Brf1 expression and Pol III gene transcription. Expression of Runx2, Brf1 and Pol III genes from the samples of human breast cancer and cell culture model were determined by the assays of RT-qPCR, immunoblot, luciferase reporter activity, immunohistochemistry, chromatin immunoprecipitation and Immunofluorescence. High expression of Runx2 is observed in the cases of breast cancer. The patients of high Runx2 expression at early stages display longer survival period, whereas the cases of high Runx2 at advanced stages reveal faster recurrence. The identification of signaling pathway indicates that JNK1 and c-Jun mediate Runx2 transcription. Repression of Runx2 reduces Brf1 expression and Pol III gene transcription. Further analysis indicates that Runx2 is colocalized with Brf1 in nucleus of breast cancer tissue. Both Runx2 and Brf1 synergistically modulate Pol III gene transcription. These studies indicate that Brf1 overexpression is able to be used as an early diagnosis biomarker of breast cancer, while high Runx2 expression indicates long survival period and faster recurrence. Runx2 mediates the deregulation of Brf1 and Pol III genes and its abnormal expression predicts the worse prognosis of breast cancer.

BC200 overexpression contributes to luminal and triple negative breast cancer pathogenesis

Background

Long non coding RNAs (lncRNAs) are RNA molecules longer than 200 nucleotides that are not translated into proteins, but regulate the transcription of genes involved in different cellular processes, including cancer. Epidemiological analyses have demonstrated that parous women have a decreased risk of developing breast cancer in postmenopausal years if they went through a full term pregnancy in their early twenties. We here provide evidence of the role of BC200 in breast cancer and, potentially, in pregnancy’s preventive effect in reducing the lifetime risk of developing breast cancer.

Methods

Transcriptome analysis of normal breast of parous and nulliparous postmenopausal women revealed that several lncRNAs are differentially expressed in the parous breast. RNA sequencing of healthy postmenopausal breast tissue biopsies from eight parous and eight nulliparous women showed that there are 42 novel lncRNAs differentially expressed between these two groups. Screening of several of these 42 lncRNAs by RT-qPCR in different breast cancer cell lines, provided evidence that one in particular, lncEPCAM (more commonly known as BC200), was a strong candidate involved in cancer progression. Proliferation, migration, invasion and xerograph studies confirmed this hypothesis.

Results

The poorly studied oncogenic BC200 was selected to be tested in vitro and in vivo to determine its relevance in breast cancer and also to provide us with an understanding of its role in the increased susceptibility of the nulliparous women to cancer. Our results show that BC200 is upregulated in nulliparous women, and breast cancer cells and tissue. The role of BC200 is not completely understood in any of the breast cancer subtypes. We here provide evidence that BC200 has a role in luminal breast cancer as well as in the triple negative breast cancer subtype.

Conclusion

When overexpressed in luminal and triple negative breast cancer cell lines, BC200 shows increased proliferation, migration, and invasion in vitro. In vivo, overexpression of BC200 increased tumor size. Although treatment for cancer using lncRNAs as targets is in its infancy, the advancement in knowledge and technology to study their relevance in disease could lead to the development of novel treatment and preventive strategies for breast cancer.

Breast cancer and cytomegalovirus

PURPOSE

To determine whether cytomegalovirus is causally associated with breast cancer and whether cytomegalovirus should be categorised as an oncogenic virus.

METHODS

We undertook a review of published epidemiological and laboratory studies, using established causal criteria: Bradford Hill criteria to determine whether cytomegalovirus is associated with breast cancer; and Evans/Mueller criteria to determine whether cytomegalovirus should be categorised as an oncogenic virus.

RESULTS

Although there are inconsistencies in the findings of published epidemiological and laboratory studies, these may be explained by factors such as: differences in timing of blood samples, differences in selection of cases and controls, or high cytomegalovirus seroprevalence among participants in the epidemiological studies; and, in the laboratory studies, differences in sample preparations, age of sample, whether or not paired breast cancer and normal breast tissue samples were used, differences in the tests, primers and/or antibodies used, differences in histological types of breast cancer studied, and/or features of the virus.

CONCLUSIONS

Overall, the results of published studies of cytomegalovirus and breast cancer suggest cytomegalovirus is a causal factor for at least some types of breast cancer. If the evidence for a link between cytomegalovirus and breast cancer continues to strengthen, further research could lead to: targeted screening; therapy using antiviral drugs; and, perhaps, primary prevention of a significant proportion of breast cancer. Vaccination against viruses has already been shown to be effective in preventing cervix and liver cancer; cytomegalovirus vaccines are already under development.

What causes patients with breast cancer to change employment?: evidence from the health insurance data in a medical facility

This study aims to make clear the following aspects of breast cancer patients and their occupation. 1. What percentage of patients have changed their working status around surgery? 2. When did patients change their employment? 3. What is the cause of the employment change? We investigated 269 patients who underwent curative surgery for primary breast cancer at one university hospital in Tokyo. Patients who were under the age of 58 at the time of surgery and had the experience of being a company or government employee during a year prior to the surgery were used as sample for analysis. To determine factors related to the employment change, multiple logistic regression analysis was performed. Nineteen percent patients changed the employment status before and after surgery. Of those, 19% changed the employment by the end of surgery month while 42% did by the fourth month after surgery. Treatment-related factors such as mastectomy and the combination of chemotherapy and hormone therapy affected changes in employment. We believe that the validity of our study can be confirmed by comparing with the previous study results. We show the potential large effects of cancer treatment on patients' daily lives.

Alcohol Intake and Abnormal Expression of Brf1 in Breast Cancer

Breast cancer is the most common malignant disease of females. Overall, one woman in every nine will get breast cancer at some time in her life. Epidemiological studies have indicated that alcohol consumption has most consistently been associated with breast cancer risk. However, the mechanism of alcohol-associated breast cancer remains to be addressed. Little is known about the effects of alcohol consumption on Brf1 (TFIIIB-related factor 1) expression and RNA Pol III gene (RNA polymerase III-dependent gene) transcription, which are responsible for protein synthesis and tightly linked to cell proliferation, cell transformation, and tumor development. Emerging evidences have indicated that alcohol induces deregulation of Brf1 and Pol III genes to cause the alterations of cell phenotypes and tumor formation. In this paper, we summarize the progresses regarding alcohol-caused increase in the expression of Brf1 and Pol III genes and analysis of its molecular mechanism of breast cancer. As the earlier and accurate diagnosis approach of breast cancer is not available yet, exploring the molecular mechanism and identifying the biomarker of alcohol-associated breast cancer are especially important. Recent studies have demonstrated that Brf1 is overexpressed in most ER+ (estrogen receptor positive) cases of breast cancer and the change in cellular levels of Brf1 reflects the therapeutic efficacy and prognosis of this disease. It suggests that Brf1 may be a potential diagnosis biomarker and a therapeutic target of alcohol-associated breast cancer.

Menstrual and reproductive factors and risk of breast cancer: A case-control study in the Fez region, Morocco

BACKGROUND

Breast cancer is the most common cancer in women worldwide. In the Moroccan context, the role of well-known reproductive factors in breast cancer remains poorly documented. The aim of this study was to explore the relationship between menstrual and reproductive factors and breast cancer risk in Moroccan women in the Fez region.

METHODS

A case-control study was conducted at the Hassan II University Hospital of Fez between January 2014 and April 2015. A total of 237 cases of breast cancer and 237 age-matched controls were included. Information on sociodemographic characteristics, menstrual and reproductive history, family history of breast cancer, and lifestyle factors was obtained through a structured questionnaire. Conditional logistic regression models were used to estimate odds ratios and 95% confidence intervals for breast cancer by menstrual and reproductive factors adjusted for potential confounders.

RESULTS

Early menarche (OR = 1.60, 95% CI: 1.08-2.38) and nulliparity (OR = 3.77, 95% CI: 1.98-7.30) were significantly related to an increased risk of breast cancer, whereas an early age at first full-term pregnancy was associated with a decreased risk of breast cancer (OR = 0.41, 95% CI: 0.25-0.65).

CONCLUSION

The results of this study confirm the role of established reproductive factors for breast cancer in Moroccan women. It identified some susceptible groups at high risk of breast cancer. Preventive interventions and screening should focus on these groups as a priority. These results should be confirmed in a larger, multicenter study.

Role of Brf1 interaction with ERα, and significance of its overexpression, in human breast cancer

TFIIB-related factor 1 (Brf1) modulates the transcription of RNA Pol III genes (polymerase-dependent genes). Upregulation of Pol III genes enhances tRNA and 5S RNA production and increases the translational capacity of cells to promote cell transformation and tumor development. However, the significance of Brf1 overexpression in human breast cancer (HBC) remains to be investigated. Here, we investigate whether Brf1 expression is increased in the samples of HBC, and we explore its molecular mechanism and the significance of Brf1 expression in HBC. Two hundred and eighteen samples of HBC were collected to determine Brf1 expression by cytological and molecular biological approaches. We utilized colocalization, coimmunoprecipitation, and chromatin immunoprecipitation methods to explore the interaction of Brf1 with estrogen receptor alpha (ERα). We determined how Brf1 and ERα modulate Pol III genes. The results indicated that Brf1 is overexpressed in most cases of HBC, which is associated with an ER-positive status. The survival period of the cases with high Brf1 expression is significantly longer than those with low levels of Brf1 after hormone treatment. ERα mediates Brf1 expression. Brf1 and ERα are colocalized in the nucleus. These results indicate an interaction between Brf1 and ERα, which synergistically regulates the transcription of Pol III genes. Inhibition of ERα by its siRNA or tamoxifen reduces cellular levels of Brf1 and Pol III gene expression and decreases the rate of colony formation of breast cancer cells. Together, these studies demonstrate that Brf1 is a good biomarker for the diagnosis and prognosis of HBC. This interaction of Brf1 with ERα and Brf1 itself are potential therapeutic targets for this disease.

Exploring a common mechanism of alcohol-induced deregulation of RNA Pol III genes in liver and breast cells

Alcohol intake is associated with numbers of different human cancers, such as hepatocellular carcinoma (HCC) and breast cancer. However, the molecular mechanism remains to be elucidated. RNA polymerase III-dependent genes (Pol III genes) deregulation elevates cellular production of tRNAs and 5S rRNA, resulting in an increase in translational capacity, which promote cell transformation and tumor formation. To explore a common mechanism of alcohol-associated human cancers, we have comparably analyzed that alcohol causes deregulation of Pol III genes in liver and breast cells. Our results reveal that alcohol enhances RNA Pol III gene transcription in both liver and breast cells. The induction of Pol III genes caused by alcohol in ER+ breast cancer lines or liver tumor lines are significantly higher than in their non-tumor cell lines. Alcohol increases cellular levels of Brf1 mRNA and protein, (which depeted) Brf1 is a key transcription factor and specifically regulate Pol III gene activity. Alcohol activates JNK1 to upregulate transcription of Brf1 and Pol III genes, whereas inhibition of JNK1 by SP600125 or its siRNA significantly decreases the induction of these genes. Furthermore, alcohol increases the rates of transformation of liver and breast cells, repressed JNK1 and Brf1 expression decrease transcription of Pol III genes and reduce the rates of colony formation of AML-12 and MCF-10 cells. Together, these studies support the idea that alcohol induces deregulation of Brf1 and RNA Pol III genes in liver and breast cells, which share a common signaling pathway to promote cell transformation. Through the common mechanism, alcohol-induced deregulation of RNA Pol III genes brings about greater phenotypic changes.

Alcohol-associated cancer and deregulation of Pol III genes

Emerging evidence indicates that alcohol intake is associated with human cancers in different organs. However, the molecular mechanism of alcohol-associated human cancers remains to be elucidated. Here, this paper aimed to clarify a novel mechanism of alcohol-promoted cell transformation and tumor development. Alcohol induces JNK1 activation and increases cellular levels of c-Jun to upregulate Brf1 expression and Pol III gene transcription, leading to an enhancement of rates of cell transformation and tumor formation.

Role of Runx2 in breast cancer-mediated bone metastasis

Breast cancer is one of the most prevalent forms of cancer in women. The currently available treatment for breast cancer is mostly curative except when it becomes metastatic. One of the major sites for metastasis of breast cancer is the bone. Homing of the circulating tumor cells is tightly regulated including a number of factors present in the cells and their microenvironment. Runx2, a transcription factor plays an important role in osteogenesis and breast cancer mediated bone metastases. One of the recent advances in molecular therapy includes the discovery of the small, non-coding microRNAs (miRNAs) and they target specific genes to reduce their expression at the post-transcriptional level. This review provides an outline of breast cancer mediated bone metastasis and summarizes the recent development on the regulation of Runx2 expression by miRNAs which can lead to novel molecular therapeutics for the same.

Microfluidic array for simultaneous detection of DNA oxidation and DNA-adduct damage

Exposure to chemical pollutants and pharmaceuticals may cause health issues caused by metabolite-related toxicity. This paper reports a new microfluidic electrochemical sensor array with the ability to simultaneously detect common types of DNA damage including oxidation and nucleobase adduct formation. Sensors in the 8-electrode screen-printed carbon array were coated with thin films of metallopolymers osmium or ruthenium bipyridyl-poly(vinylpyridine) chloride (OsPVP, RuPVP) along with DNA and metabolic enzymes by layer-by-layer electrostatic assembly. After a reaction step in which test chemicals and other necessary reagents flow over the array, OsPVP selectively detects oxidized guanines on the DNA strands, and RuPVP detects DNA adduction by metabolites on nucleobases. We demonstrate array performance for test chemicals including 17β-estradiol (E2), its metabolites 4-hydroxyestradiol (4-OHE2), 2-hydroxyestradiol (2-OHE2), catechol, 2-nitrosotoluene (2-NO-T), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), and 2-acetylaminofluorene (2-AAF). Results revealed DNA-adduct and oxidation damage in a single run to provide a metabolic-genotoxic chemistry screen. The array measures damage directly in unhydrolyzed DNA, and is less expensive, faster, and simpler than conventional methods to detect DNA damage. The detection limit for oxidation is 672 8-oxodG per 106 bases. Each sensor requires only 22 ng of DNA, so the mass detection limit is 15 pg (∼10 pmol) 8-oxodG.

Health-related Quality of Life in Metastatic and Adjuvant Breast Cancer Patients

Introduction: When cancer patients have advanced disease and a primary cure is no longer possible, the focus is on maintaining the patient's quality of life. Recent therapeutic advances in breast cancer treatment mean that even patients with metastatic disease can remain stable for long periods of time. The aim of this study was to look at the health-related quality of life (HRQL) of these patients and compare it with data for the general population and to show the differences in outcomes for different survey instruments used to measure quality of life. Material and Methods: A total of 96 breast cancer patients with metastatic disesae or receiving adjuvant therapy were questioned about their quality of life. Patients were investigated using the established survey instruments EORTC QLQ-C30, EORTC QLQ-BR23, EQ-5D-5L and EQ VAS. All patients filled out questionnaires. Statistical analysis was done using MS Excel and SPSS. Results: Although the questionnaires were completed at the same time, the different questionnaires showed significant differences with regard to the level of stress experienced by the patient. When the EQ VAS questionnaire was used, the patient's current state of health was assessed as significantly better than with the EORTC QLQ-C30. Overall, all aspects of patients' quality of life were found to be in need of optimization and HRQL of patients was significantly poorer in all areas compared to the reference population. Conclusion: To improve the quality of life of patients with metastatic disease, it is necessary to continuously monitor the success of therapy. The choice of survey tools is highly relevant as assessments differ considerably depending on the choice of questionnaire.

Total Effective Xenoestrogen Burden in Serum Samples and Risk for Breast Cancer in a Population-Based Multicase-Control Study in Spain

BACKGROUND

Most studies on endocrine-disrupting chemicals and breast cancer have focused on single compounds and have produced inconclusive findings.

OBJECTIVES

We assessed the combined estrogenic effects of mixtures of xenoestrogens in serum and their relationship to breast cancer risk.

METHODS

A total of 186 incident pretreatment breast cancer cases and 196 frequency-matched controls were randomly sampled from a large population-based multicase-control study in Spain. The total effective xenoestrogen burden attributable to organohalogenated xenoestrogens (TEXB-α) and endogenous hormones and more polar xenoestrogens (TEXB-β) was determined in serum samples using high-performance liquid chromatography and E-Screen bioassay. Odds ratios for breast cancer comparing tertiles of serum TEXB-α and TEXB-β were estimated using logistic models, and smooth risk trends were obtained using spline models.

RESULTS

Cases had higher geometric mean TEXB-α and TEXB-β levels (8.32 and 9.94 Eeq pM/mL, respectively) than controls (2.99 and 5.96 Eeq pM/mL, respectively). The fully adjusted odds ratios for breast cancer (95% confidence intervals) comparing the second and third tertiles of TEXB-α with the first tertile were 1.77 (0.76, 4.10) and 3.45 (1.50, 7.97), respectively, and those for TEXB-β were 2.35 (1.10, 5.03) and 4.01 (1.88, 8.56), respectively. A steady increase in risk was evident across all detected TEXB-α levels and a sigmoidal trend was observed for TEXB-β. Individual xenoestrogens showed weak and opposing associations with breast cancer risk.

CONCLUSIONS

This is the first study to show a strong positive association between serum total xenoestrogen burden and breast cancer risk, highlighting the importance of evaluating xenoestrogen mixtures, rather than single compounds, when studying hormone-related cancers.

CITATION

Pastor-Barriuso R, Fernández MF, Castaño-Vinyals G, Whelan D, Pérez-Gómez B, Llorca J, Villanueva CM, Guevara M, Molina-Molina JM, Artacho-Cordón F, Barriuso-Lapresa L, Tusquets I, Dierssen-Sotos T, Aragonés N, Olea N, Kogevinas M, Pollán M. 2016. Total effective xenoestrogen burden in serum samples and risk for breast cancer in a population-based multicase-control study in Spain. Environ Health Perspect 124:1575-1582; http://dx.doi.org/10.1289/EHP157.

Gene expression profiling of the 8q22-24 position in human breast cancer: TSPYL5, MTDH, ATAD2 and CCNE2 genes are implicated in oncogenesis, while WISP1 and EXT1 genes may predict a risk of metastasis

Gene expression profiling has been suggested to predict breast cancer outcome. The prognostic value of the 8q22-24 position in breast cancer remains to be elucidated. The present study evaluated expression patterns of the genes located at this position in metastatic and non-metastatic breast cancer. A total of 85 patients with recurrent/metastatic (n=15) and non-metastatic (n=70) early-stage, estrogen receptor-positive and lymph node-negative breast tumors were included. In addition, 15 normal breast tissue samples were used as controls. Demographic and clinical features were recorded. Subsequently, mRNA copy numbers of exostosin glycosyltransferase 1 (EXT1), WNT1 inducible signaling pathway protein 1 (WISP1), ATPase family, AAA domain containing 2 (ATAD2), TSP-like 5 (TSPYL5), metadherin (MTDH) and cyclin E2 (CCNE2) genes were measured by reverse transcription-quantitative polymerase chain reaction assay. The expression of EXT1 and WISP1 exhibited a significant decline in the metastatic breast cancer group compared to the control (P=0.015 and P=0.012, respectively). The expression of TSPYL5, MTDH and ATAD2 was significantly decreased in the metastatic (P=0.002, P=0.018 and P=0.016, respectively) and non-metastatic (P=0.038, P=0.045 and P=0.000, respectively) breast cancer groups compared with the control. The expression of CCNE2 in the metastatic and non-metastatic breast cancer groups was significantly increased compared with the control (P=0.002 and P=0.001, respectively). WISP1 expression demonstrated a correlation with patient age and tumor size, and TSPYL5 expression was correlated with lymphovascular invasion. None of the genes investigated exhibited any correlation with stage and grade of disease. The TSPYL5, MTDH, ATAD2 and CCNE2 genes may be implicated in the pathogenesis of human breast cancer, while the WISP1 and EXT1 genes may have the potential to serve as promising indicators of the risk of metastasis. However, further studies are required to validate these results.

The incidence rates of endometrial hyperplasia and endometrial cancer: a four-year population-based study

Introduction

The aim of this study was to determine the incidence rates of endometrial hyperplasia (EH) and endometrial cancer (EC) in the Republic of Korea using national insurance claim data generated from 2009 to 2012.

Materials and Methods

Data that were generated from 2009 to 2012 were sourced from the Korean Health Insurance Review and Assessment Service-National Inpatients Sample database. The data from women who were assigned diagnosis codes representing EH or EC within 1 month of being assigned codes that corresponded to procedures that included endometrial biopsies and several types of gynecologic surgeries to obtain endometrial pathology samples, were selected for analysis.

Results

Data from 2,477,424 women were entered into the database between 2009 and 2012, and the data from 1,868 women with EH and 868 women with EC were extracted for analysis. The mean ages of the patients were 44.1 ± 0.4 years for those with EH and 52.7 ± 0.6 years for those with EC. The EH and EC incidence rates were 37 per 100,000 woman-years and 8 per 100,000 woman-years, respectively. The EH and EC incidence rates peaked when the women were in their late forties and fifties, respectively.

Conclusions

The EH and EC incidence rates determined in this study were somewhat lower than those determined from previous studies. Further studies are required that adjust the data for race, menopausal hormone therapy, and obesity.

Effects of lifelong exercise training on mammary tumorigenesis induced by MNU in female Sprague-Dawley rats

Breast cancer is the most common malignancy in women worldwide. Several studies have suggested that exercise training may decrease the risk of breast cancer development. This study aimed to evaluate the effects of long-term exercise training on mammary tumorigenesis in an animal model of mammary cancer. Fifty female Sprague-Dawley rats were randomly divided into four groups: MNU sedentary, MNU exercised, control sedentary and control exercised. Animals from MNU groups received an intraperitoneal administration of N-methyl-N-nitrosourea (MNU). Animals were exercised on a treadmill during 35 weeks. When animals were killed, blood samples were collected to determine the hematocrit and to perform the biochemical analysis. Mammary tumors were collected and histologically evaluated; the expression of ERs α and β was evaluated in tumor sections by immunohistochemistry. All survived animals from both MNU groups developed mammary tumors. The number of mammary tumors (p > 0.05) and lesions (p = 0.056) was lower in MNU exercised than in MNU sedentary animals. MNU exercised animals showed lower number of malignant lesions than MNU sedentary animals (p = 0.020). C-reactive protein serum concentration was lower in exercised animals; however, the levels of 17-β estradiol were higher in exercised animals. Tumors from exercised animals exhibited higher expression of ER α than tumors from sedentary animals (p < 0.05). This study analyzes the impact of the longest exercise training protocol on mammary tumorigenesis ever performed. We concluded that the lifelong endurance training has beneficial effects on mammary tumorigenesis in female rats (reduced the inflammation, the number of mammary tumors and lesions, and histological grade of malignancy). Additionally, the mammary tumors from MNU exercised group exhibited higher immunoexpression of ER α that is an indicator of well-differentiated tumors and better response to hormone therapy.

Alteration of BRCA1 expression affects alcohol-induced transcription of RNA Pol III-dependent genes

Emerging evidence has indicated that alcohol consumption is an established risk factor for breast cancer. Deregulation of RNA polymerase III (Pol III) transcription enhances cellular Pol III gene production, leading to an increase in translational capacity to promote cell transformation and tumor formation. We have reported that alcohol intake increases Pol III gene transcription to promote cell transformation and tumor formation in vitro and in vivo. Studies revealed that tumor suppressors, pRb, p53, PTEN and Maf1 repress the transcription of Pol III genes. BRCA1 is a tumor suppressor and its mutation is tightly related to breast cancer development. However, it is not clear whether BRCA1 expression affects alcohol-induced transcription of Pol III genes. At the present studies, we report that restoring BRCA1 in HCC 1937 cells, which is a BRCA1 deficient cell line, represses Pol III gene transcription. Expressing mutant or truncated BRCA1 in these cells does not affect the ability of repression on Pol III genes. Our analysis has demonstrated that alcohol induces Pol III gene transcription. More importantly, overexpression of BRCA1 in estrogen receptor positive (ER+) breast cancer cells (MCF-7) decreases the induction of tRNA(Leu) and 5S rRNA genes by alcohol, whereas reduction of BRCA1 by its siRNA slightly increases the transcription of the class of genes. This suggests that BRCA1 is associated with alcohol-induced deregulation of Pol III genes. These studies for the first time demonstrate the role of BRCA1 in induction of Pol III genes by alcohol and uncover a novel mechanism of alcohol-associated breast cancer.

Psychosocial impact of breast cancer diagnosis among omani women

OBJECTIVES

The aim of this study was to explore different psychosocial impacts on Omani women diagnosed with breast cancer.

METHODS

Semi-structured individual interviews were conducted with 19 Omani women diagnosed with breast cancer to describe the impact of the disease on their personal and social life. Women were recruited from wards and out-patient clinics at the Sultan Qaboos University Hospital, Muscat.

RESULTS

Four main themes emerged. These were: a) factors related to psychological distress of the disease and uncertainty (worry of death, interference with work and family responsibilities, searching for hope/cure, travelling overseas); b) reactions of family members (shocked, saddened, unity, pressure to seek traditional treatments); c) views of society (sympathy, isolation, reluctant to disclose information); and d) worries and threats about the future (side effects of chemotherapy, spread of the disease, effect on offspring).

CONCLUSION

Breast cancer diagnosis has several devastating psychosocial impacts on women in Oman. Healthcare professionals working with women with breast cancer should be aware of the different psychosocial impacts of the disease on women's lives. Appropriate measures must be taken by the decision makers whenever needed, including enforcing positive views and support of Oman's society towards women with breast cancer.

Tamoxifen represses alcohol-induced transcription of RNA polymerase III-dependent genes in breast cancer cells

Alcohol consumption in women has been associated with an increased risk of breast cancer, particular in estrogen receptor positive (ER+) cases. Deregulation of RNA polymerase III-dependent (Pol III) transcription enhances cellular tRNAs and 5S rRNA production, leading to an increase in translational capacity to promote cell transformation and tumor formation. Our recent studies demonstrated that alcohol induces Brf1 expression and Pol III gene transcription via ER. Here, we report that Tamoxifen (Tam) inhibits the induction of Brf1 and Pol III genes in ER+ breast cancer cells. Further analysis indicates that alcohol increases c-Jun expression to upregulate the transcription of Brf1 and Pol III genes, whereas Tam reduces c-Jun expression to repress the transcription of Brf1. Repression of cJun decreases cellular levels of ERα and Brf1. Alcohol-dependent increased occupancy of Brf1 in Pol III gene promoters is reduced by Tam. The repression of Brf1 and Pol III genes by Tam reduces alcohol-induced cell proliferation and colony formation. Together, these results indicate that Tam inhibits alcohol-induced Brf1 expression through c-Jun and ERα to downregulate Pol III gene transcription. Our studies uncover a new mechanism of Tam-treated ER+ breast cancer, by which Tam inhibits tumor growth through repressing Pol III gene transcription.

Serum and saliva protein levels in females with breast cancer

The aim of the present study was to investigate the change in the total protein content between the serum and saliva of female patients with breast cancer and in healthy females. The study was conducted between October 2012 and November 2013. There were 80 females in the present study with 40 breast cancer patients and 40 healthy control subjects, with an age range of 50-70 years. The results of the study showed that the mean value ± standard deviation of the total serum protein in patients with breast cancer was 7.63±0.41 g/dl, whereas in the healthy subjects it was 6.14±1.84 g/dl. The total salivary protein measurement was 0.14±0.07 g/dl and 0.25±0.09 g/dl in the breast cancer and healthy group, respectively. Therefore, it can be concluded that the total serum protein was higher in female patients with breast cancer, whereas the levels in the saliva were lower compared to the healthy female group. The results of the present study indicate that serum protein levels may be used for the diagnosis of breast cancer.

Breast cancer: trends in international incidence in men and women

Background:

The age-standardised incidence of breast cancer varies geographically, with rates in the highest-risk countries more than five times those in the lowest-risk countries.

Methods:

We investigated the correlation between male (MBC) and female breast cancer (FBC) incidence stratified by female age-group (<50 years, and ⩾50 years) and used Poisson regression to examine male incidence rate ratios according to female incidence rates.

Results:

Age-adjusted breast cancer incidence rates for males and females share a similar geographic distribution (Spearman's correlation=0.51; P<0.0001). A correlation with male incidence rates was found for the entire female population and for women aged 50 years and over. Breast cancer incidence rates in males aged <50 years were not associated with FBC incidence, whereas those in males aged ⩾50 years were. MBC incidence displays a small ‘hook' similar to the Clemmesen's hook for FBC, but at a later age than the female hook.

Interpretation:

Further investigation of possible explanations for these patterns is warranted. Although the incidence of breast cancer is much lower in men than in women, it may be possible to identify a cause common to both men and women.

Molecular pathways involved in pregnancy-induced prevention against breast cancer

Pregnancy produces a protective effect against breast cancer in women who had their first full term pregnancy (FTP) in their middle twenties. The later in life the first delivery occurs, the higher the risk of breast cancer development. Also, transiently during the postpartum period, the risk of developing breast cancer increases. This transient increased risk is taken over by a long-lasting protective period. The genomic profile of parous women has shown pregnancy induces a long-lasting "genomic signature" that explains the preventive effect on breast cancer. This signature reveals that chromatin remodeling is the driver of the differentiation process conferred by FTP. The chromatin remodeling process may be the ultimate step mediating the protection of the breast against developing breast cancer in post-menopausal years.

Breast cancer and dietary patterns: a systematic review

This systematic review collates research on the topic of dietary patterns and breast cancer risks. The literature search targeted epidemiological studies published up to December 2012 and was conducted using the Medline (U.S. National Library of Medicine, Bethesda MD, USA) and Lilacs (Latin American and Caribbean Health Sciences, São Paulo, Brazil) databases. The following search terms were used: breast cancer, breast neoplasm, breast carcinoma, diet, food, eating habits, dietary patterns, factor analysis, and principal component analysis. Only studies that used factor analysis techniques and/or principal component analysis were eligible, and a total of 26 studies were included. The findings of these studies suggest the Mediterranean dietary pattern and diets composed largely of vegetables, fruit, fish, and soy are associated with a decreased risk of breast cancer. There was no evidence of an association between traditional dietary patterns and risk of breast cancer, and only one study showed a significant increase in risk associated with the Western dietary pattern. Diets that include alcoholic beverages may be associated with increased risk.

Exposure to estrogen and ionizing radiation causes epigenetic dysregulation, activation of mitogen-activated protein kinase pathways, and genome instability in the mammary gland of ACI rats

The impact of environmental mutagens and carcinogens on the mammary gland has recently received a lot of attention. Among the most generally accepted carcinogenic agents identified as factors that may increase breast cancer incidence are ionizing radiation and elevated estrogen levels. However, the molecular mechanisms of mammary gland aberrations associated with radiation and estrogen exposure still need to be further elucidated, especially the interplay between elevated hormone levels and radiation. Therefore, in the present study, we investigated molecular changes induced in rat mammary gland tissue by estrogen, ionizing radiation, and the combined action of these two carcinogens using a well-established ACI rat model. We found that continuous exposure of intact female ACI rats to elevated levels of estrogen or to both estrogen and radiation resulted in significant hyperproliferative changes in rat mammary glands. In contrast, radiation exposure alone did not induce hyperplasia. Interestingly, despite the obvious disparity in mammary gland morphology, we did not detect significant differences in the levels of genomic methylation among animals exposed to estrogen, radiation, or both agents together. Specifically, we observed a significant global genomic hypomethylation at 6 weeks of exposure. However, by 12 and 18 weeks, the levels of global DNA methylation returned to those of age-matched controls. We also found that combined exposure to radiation and estrogen significantly altered the levels of histone H3 and H4 methylation and acetylation. Most importantly, we for the first time demonstrated that estrogen and radiation exposure caused a significant induction of p42/44 MAPK and p38 pathways that was paralleled by elevated levels of H3S10 phosphorylation, a well-established biomarker of genome and chromosome instability. The precise role of MAPK pathways and their inter-relationship with H3S10 phosphorylation and genome instability in mammary gland tissues needs to be explored further.

ERα mediates alcohol-induced deregulation of Pol III genes in breast cancer cells

The association of alcohol consumption and breast cancer is more pronounced in cases that are positive for estrogen receptor (ER+) than in cases that are negative (ER-). Its mechanism remains to be determined. Deregulation of RNA polymerase III (Pol III) transcription enhances cellular tRNAs and 5S rRNA production, increasing translational capacity to promote cell transformation and tumor formation. Here, we report that alcohol increases Pol III gene transcription in both normal and cancer breast cell lines. The induction in ER+ breast cancer cells (MCF-7) is significantly higher than in ER- normal breast cells (MCF-10A, MCF-10F and MCF-12A) and is correlated with ER expression. E2 causes <2-fold increase in Pol III gene transcription. The addition of ethanol to this system now produces a 10-15-fold increase. Ethanol increases ERα expression, resulting in an increase in Brf1 protein and mRNA levels. In addition, ethanol markedly stimulates phosphorylation of JNK1, but not JNK2. Inhibition of JNK1 decreases ERE-Luc reporter activity and represses expression of ERα, Brf1 and Pol III genes. Reduction of ERα by its small interfering RNA represses Brf1 and Pol III gene transcription. Ethanol with E2 produces larger and more numerous colonies. Repression of ERα or Brf1 inhibits alcohol-induced cell transformation. Together, these results support the idea that alcohol increases ERα expression through JNK1 to elevate Brf1 expression and Pol III gene transcription to bring about greater phenotypic changes. These studies demonstrate that ERα mediates Pol III gene transcription through Brf1, suggesting that ERα may play a critical role in alcohol-induced deregulation of Pol III genes in ER+ breast cancer development.

Breast cancer incidence by estrogen receptor status in Denmark from 1996 to 2007

During the past 50 years, breast cancer incidence has increased by 2-3 % annually. Despite many years of testing for estrogen receptors (ER), evidence is scarce on breast cancer incidence by ER status. The aim of this paper was to investigate the increase in breast cancer incidence by ER status. Data were obtained from the clinical database of the Danish Breast Cancer Cooperative Group which holds nationwide data on diagnosis, including pathology, treatment, and follow-up on primary breast cancers since 1977. All Danish women <80 years diagnosed with primary breast cancer 1996-2007 were identified in this prospective register based study. ER status was evaluated using immunohistochemical staining by standardized laboratory methods in the Danish Pathology Departments and reported to the database. From 1996 to 2007, breast cancer incidence increased overall with a tendency to level off after 2002. In all women a significant decrease was found in ER unknown tumors. However, in both pre- and postmenopausal women, significant increases were seen in incidence of ER+ tumors; though the increase levelled off for premenopausal women after 2002. In postmenopausal women, the incidence of ER- breast cancer decreased significantly throughout the period. In women <35 years, we found a minor non-significant increase in both ER+ and ER- tumors. ER unknown decreased in all women and was the most distinct in premenopausal women aged 35+. We found a significant increase in ER+ breast cancer incidence in postmenopausal women whereas the incidence in premenopausal women (aged 35+) levelled off after 2002.

Endocrine-active chemicals in mammary cancer causation and prevention

Endocrine-active chemicals alter or mimic physiological hormones. These compounds are reported to originate from a wide variety of sources, and recent studies have shown widespread human exposure to several of these compounds. Given the role of the sex steroid hormone, estradiol, in human breast cancer causation, endocrine-active chemicals which interfere with estrogen signaling constitute one potential factor contributing to the high incidence of breast cancer. Thus, the aim of this review is to examine several common endocrine-active chemicals and their respective roles in breast cancer causation or prevention. The plastic component, bisphenol A (BPA), the synthetic estrogen, diethylstilbestrol (DES), the by-product of organic combustion, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the soy component, genistein, and the red grape phytoalexin, resveratrol, have some degree of structural similarities to each other and estradiol. However, despite these structural similarities, the in vitro and in vivo properties of each of these chemicals vary greatly in terms of breast cancer causation and prevention. Early life exposure to BPA and DES increases rodent susceptibility to chemically induced mammary carcinogenesis, presumably through retardation of normal mammary gland maturation and/or disrupting the ratio of cell proliferation and apoptosis in the mammary gland. On the other hand, early exposures to genistein and resveratrol protect rodents against chemically induced and spontaneous mammary cancers. This is reported to occur through the ability of genistein and resveratrol to accelerate mammary gland maturation. Interestingly, TCDD, which is the most structurally dissimilar to the above chemicals and functions as an anti-estrogen, also increases chemically induced mammary carcinogenesis through retardation of mammary gland maturation. This article is part of a Special Issue entitled 'Endocrine disruptors'.

Gold-containing indoles as anticancer agents that potentiate the cytotoxic effects of ionizing radiation

This report describes the design and application of several distinct gold-containing indoles as anticancer agents. When used individually, all gold-bearing compounds display cytostatic effects against leukemia and adherent cancer cell lines. However, two gold-bearing indoles show unique behavior by increasing the cytotoxic effects of clinically relevant levels of ionizing radiation. Quantifying the amount of DNA damage demonstrates that each gold-indole enhances apoptosis by inhibiting DNA repair. Both Au(I)-indoles were tested for inhibitory effects against various cellular targets including thioredoxin reductase, a known target of several gold compounds, and various ATP-dependent kinases. While neither compound significantly inhibits the activity of thioreoxin reductase, both showed inhibitory effects against several kinases associated with cancer initiation and progression. The inhibition of these kinases provides a possible mechanism for the ability of these Au(I)-indoles to potentiate the cytotoxic effects of ionizing radiation. Clinical applications of combining Au(I)-indoles with ionizing radiation are discussed as a new strategy to achieve chemosensitization of cancer cells.

Novel BRCA1 deleterious mutation (c.1949_1950delTA) in a woman of Senegalese descent with triple-negative early-onset breast cancer

Limited information exists regarding BRCA1 and BRCA2 genetic testing and genetic diversity in BRCA1 and BRCA2 in sub-Saharan African populations. We report a novel mutation that consists of a deletion of 2 bp (c.1949_1950delTA) in the exon 11 of the BRCA1 gene. This is a frameshift mutation that causes the disruption of the translational reading frame resulting in a premature stop codon downstream in the BRCA1 protein. The mutation was present in a Senegalese woman with a triple-negative breast tumor and a family history of breast cancer.

Human chorionic gonadotropin and a 15 amino acid hCG fragment of the hormone induce downregulation of the cytokine IL-8 receptor in normal breast epithelial cells

Cytokine receptors are associated with tumor cell growth by increasing proliferation, metastasis and regulating self-renewal of cancer stem cells (SCs). There is a strong association between cytokine IL-8 receptor (CXCR1) over-expression and cells displaying SC characteristics. Human chorionic gonadotropin (hCG) causes differentiation, inhibition of cell proliferation and increased apoptosis of the breast epithelium. hCG receptor (LHCGR) expression in breast tumors and in breast cancer cell lines is undetectable or low. In this study, our objective was to assess and compare the effects of hCG and a 15 amino acid hCG fragment of the hormone on mRNA expression of CXCR1 and LHCGR on normal breast epithelial cells (MCF-10F) by real time RT-PCR after treatment with hCG or a hCG fragment for 15 days. Cell proliferation was also measured. hCG and the hCG fragment decreased cell proliferation in both groups. The compounds upregulated LHCGR expression and downregulated CXCR1 expression. It is possible to postulate that an increase of LHCGR mRNA seems to respond to the decrease of CXCR1 expression. These genes probably act synergistically to reduce the amount of cancer SCs in the mammary gland. Thereby, the use of hCG or the hCG fragment as a therapeutic or preventive tool should be considered.

A population-based cohort study of HRT use and breast cancer in Korea

The incidence of breast cancer has recently been ranked first in Korea. This is a population-based cohort study that aims to evaluate the risk of breast cancer from the use of hormone replacement therapy (HRT). A total of 9579 participants were observed between January 1998 and June 2004; 6108 women who took HRT constituted the HRT group, and 3471 women who did not take HRT constituted the non-HRT group. Using the database from the Korea Central Cancer Registry, the authors examined the incidence of breast cancer from HRT. A total of 26 cases of breast cancer developed in the HRT group as compared with the 13 cases in the non-HRT group, during the follow-up period. The relative risk of developing breast cancer in the HRT group was 1.16 times higher than in the non-HRT group, with a population attributable risk of 29.9%. The risk of breast cancer in the HRT group increased when the risk factors were adjusted in the model.

Breast cancer patients in Libya: Comparison with European and central African patients

The present study evaluated the incidence of breast cancer in Libya and described the clinicopathological and demographic features. These features were then compared with corresponding data from patients from sub-Saharan Africa (Nigeria) and Europe (Finland). The study consisted of 234 patients with breast carcinoma, admitted to the African Oncology Institute in Sabratha, Libya, during the years 2002-2006. The pathological features were collected from pathology reports, patient histories from hospital files and the Sabratha Cancer Registry. The demographic differences between the Libyan, Nigerian and Finnish populations were prominent. The mean age of breast cancer patients in Libya was 46 years which was almost identical to that of Nigeria, but much lower than that of Finland. The Libyan breast cancer incidence was evaluated as 18.8 per 100,000 female individuals. This incidence was markedly higher in Finland, but was also high in Nigeria. Libyan and Nigerian breast cancer is predominantly of premenopausal type and exhibits unfavorable characteristics such as high histological grade and stage, large tumor size and frequent lymph node metastases. However, the histological types and histopathological risk features show similar importance regarding survival as European breast cancer cases. Survival in Libya ranks between the rates of survival in Nigeria (lowest) and Finland (highest). In conclusion, in Libya and other African countries, premenopausal breast cancer is more common than postmenopausal breast cancer. However, the opposite is true for Europe. Population differences may be involved, as suggested by the known variation, in the distribution of genetic markers in these populations. Different types of environmental impacts, however, cannot be excluded.

Estimation of potential excess cancer incidence in pediatric 201Tl imaging

OBJECTIVE

Little information is available regarding doses of ionizing radiation from medical imaging in the growing population of children undergoing therapy for cancer who are at risk of developing second cancers. The purpose of our study was to estimate the potential excess lifetime cancer incidence and mortality associated with thallium bone imaging in pediatric patients.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of pediatric patients treated between August 1991 and December 2003 for newly diagnosed osteosarcoma who underwent 201Tl imaging as part of the treatment protocol. According to age at diagnosis and doses of 201Tl, we estimated the excess cancer incidence and cancer mortality for boys and girls at 5 and 15 years old.

RESULTS

The study cohort consisted of 73 patients, 32 males (median age at diagnosis, 14.8 years; age range, 8.1-20.1 years) and 41 females (median age at diagnosis, 13.3 years; age range, 6.0-20.7 years). Patients underwent a total of three 201Tl studies with a median dose of 4.4 mCi (162.8 MBq) (range, 2.2-8.4 mCi [81.4-310.8 MBq]) per study. Total median cumulative patient radiation dose for 201Tl studies was 18.6 rem (186 mSv) (range, 8.4-44.2 rem [84-442 mSv]) for males and 21.5 rem (215 mSv) (range, 7.0-43.8 rem [70-438 mSv]) for females. Estimated excess cancer incidence was 6.0 per 100 (male) and 13.0 per 100 (female) if exposed by 5 years of age; 2.0 per 100 (male) and 3.1 per 100 (female) by 15 years of age. Estimated excess cancer mortality was 3.0 per 100 for males and 5.2 per 100 for females at 5 years of age; 1.0 per 100 (male) and 1.4 per 100 (female) exposed at 15 years of age.

CONCLUSION

Further reduction of doses in younger patients is needed to consider 201Tl a viable option for imaging osteosarcoma.

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'.

Assessment of breast cancer opportunistic screening by clinical-pathological indicators: a population-based study

BACKGROUND

Although some clinical-pathological features of breast cancers, such as the incidence of ductal cancer in situ (DCIS) and the diameter of invasive tumours, are sensitive indicators of early detection, comprehensive population-based studies of opportunistic screening are needed.

METHODS

Cases of DCIS or invasive breast cancer diagnosed in 1996-2007 were identified from the Ticino Cancer Registry (south of Switzerland). Time trends of age-adjusted incidence and mortality, as well as main clinical-pathological features, such as tumour diameter, AJCC stage and histological grade, were analysed.

RESULTS

A total of 3047 incident cases of female breast cancer were identified. The proportion of DCIS with respect to invasive cases increased from 5.8% in the period 1996-2001 to 6.4% in the period 2002-2007. The median tumour size of invasive cancers decreased from 20 mm in 1996-2001 to 18 mm in 2002-2007 (P<0.0001). An increase in well/moderately differentiated invasive tumours, from 67% in the period 1996-2001 to 73% in 2002-2007 (P<0.001), was detected and resulted in an Annual Percentage Change of incidence of 2.8 (95% confidence interval: 1.3; 4.3).

CONCLUSION

An opportunistic screening strategy can lead to an improvement of prognostic features at diagnosis, but these features are still less favourable than those achieved by organised screening programmes.

Breast cancer prevention

We have developed a new approach for breast cancer prevention, capitalizing in the preventive effect of early first full-term pregnancy, hormonally induced differentiation and our ability to identify specific genomic signatures that allow us to predict risk reduction. Early pregnancy imprints in the breast permanent genomic changes or a 'signature' that reduces the susceptibility of this organ to cancer. At cellular level, what we have achieved is the shifting of the Stem Cell 1 population, highly susceptible to cancer, to a population of Stem Cell 2 that is refractory to carcinogenesis. In a case-control study, we have compared the gene expression profile in normal breast tissue from nulliparous and parous postmenopausal women with (case) and without (control) breast cancer. We have determined that early first full-term pregnancy induces a specific genomic signature in the postmenopausal breast that is the biomarker for the Stem cell 2. The Stem cell 2 contains specific genes controlling transcription, RNA processing, immune response, apoptosis and DNA repair. We have further detected in the plasma, using an ELISA assay, the proteins coded by the gene signature. We are developing clinical trials to demonstrate the proof of the principle that r-hCG can induce in the human breast a genomic signature of the Stem cell 2. This is a concept that challenges the currently available chemopreventive agents that need to be given for extended periods for maintaining the suppression of a specific metabolic pathway or the abrogation of the function of an organ.