Unique features of breast cancer in Asian women--breast cancer in Taiwan as an example

Examining the Role of Resilience, Posttraumatic Growth, and Quality of Life in Women with Breast Cancer: A Serial Multiple Mediator Model Approach

OBJECTIVES

It is unclear how resilience and posttraumatic growth help women with breast cancer face cancer-related symptom distress. This study included both resilience and posttraumatic growth as mediators in a serial multiple mediator model to examine changes in the relationship between symptom distress and quality of life among women with breast cancer.

DATA SOURCES

We conducted the descriptive, cross-sectional study in Taiwan. Data were collected using a survey that assessed symptom distress, resilience, posttraumatic growth, and quality of life. A serial multiple mediator model examined one direct and three specific indirect effects of symptom distress on quality of life through resilience and posttraumatic growth. All 91 participants reported the presence of symptom distress and moderate levels of resilience. Quality of life was significantly associated with symptom distress (b = -1.04), resilience (b = 0.18), and posttraumatic growth (b = 0.09). The indirect effect of symptom distress on quality of life through resilience alone was statistically significant (b = -0.23, 95% CI -0.44 to -0.07) and statistically greater than the specific indirect effect through resilience and posttraumatic growth combined (b = -0.21, 95% CI -0.40 to -0.05).

CONCLUSION

Resilience plays a unique role in reducing the impact of symptom distress on the quality of life among women with breast cancer.

IMPLICATIONS FOR NURSING PRACTICE

Given the importance of resilience to quality of life, oncology nurses can assess the resilience of women with breast cancer and help identify available internal, external, and existential resources to strengthen their resilience.

Urban-Rural Disparity in Birth Cohort Effects on Breast Cancer Incidence

Breast cancer is the most commonly diagnosed cancer among women worldwide. Studies have reported minimal birth cohort effects on the incidence rates of breast cancer in Western countries but have reported notable birth cohort effects in some Asian countries. The risks of breast cancer may also vary within a country. In the present study, we abstracted female invasive breast cancer data from the Taiwan Cancer Registry for the period 1997-2016. We used the age-period-cohort model to compare birth cohort effects on breast cancer incidence rates between urban and rural regions in Taiwan. We identified a notable urban-rural disparity in birth cohort effects on breast cancer incidence rates in women in Taiwan. The incidence rates in the urban regions were higher than those in the rural regions across all cohorts. However, the incidence rates rose faster in the rural regions than in the urban regions across the cohorts. The risks of breast cancer observed for women born in 1992 were approximately 22 and 11 times than those observed for women born in 1917 in rural and urban regions, respectively. The observed gap in breast cancer incidence rates between the urban and rural regions gradually disappeared across the cohorts. Accordingly, we speculate that urbanization and westernization in Taiwan may be the drivers of female breast cancer incidence rates across birth cohorts.

Combination of furosemide, gold, and dopamine as a potential therapy for breast cancer

Breast cancer is one of the leading causes of death in women worldwide. Initially, it develops in the epithelium of the ducts or lobules of the breast glandular tissues with limited growth and the potential to metastasize. It is a highly heterogeneous malignancy; however, the common molecular mechanisms could help identify new targeted drugs for treating its subtypes. This study uses computational drug repositioning approaches to explore fresh drug candidates for breast cancer treatment. We also implemented reversal gene expression and gene expression-based signatures to explore novel drug candidates computationally. The drug activity profiles and related gene expression changes were acquired from the DrugBank, PubChem, and LINCS databases, and then in silico drug screening, molecular dynamics (MD) simulation, replica exchange MD simulations, and simulated annealing molecular dynamics (SAMD) simulations were conducted to discover and verify the valid drug candidates. We have found that compounds like furosemide, gold, and dopamine showed significant outcomes. Furthermore, the expression of genes related to breast cancer was observed to be reversed by these shortlisted drugs. Therefore, we postulate that combining furosemide, gold, and dopamine would be a potential combination therapy measurement for breast cancer patients.

Estrogen-DNA Adducts and Breast Cancer Risk in Premenopausal Asian Women

The incidence of breast cancer among premenopausal women has been increasing rapidly in recent decades in East Asia. This case-control study investigated whether estrogen-DNA adducts were associated with breast cancer risk in Taiwan. The control group (n = 146) comprised healthy female volunteers and women with non-proliferative breast disease. The case group (n = 221) comprised women either with proliferative benign breast disease or breast cancer. The ratios of estrogen-DNA adducts to their respective metabolites and conjugates in plasma were analyzed using ultraperformance LC/MS-MS. The SNPs of CYP1A1, CYP1B1, and COMT were genotyped. Logistic regression model was used to compare the estrogen-DNA adduct ratios between the two groups. The estrogen-DNA adduct ratio in the case group was significantly higher than that in the control group (median ratio: 58.52 vs. 29.36, P = 0.004). A multiple logistic regression model demonstrated that a unit increase in the natural log of the estrogen-DNA adduct ratio in premenopausal women was a significant predictor of breast cancer risk, with an estimated hazard ratio of 1.718 (1.444-2.046, P < 0.001). However, the CYP1A1, CYP1B1, and COMT SNPs were not associated with the estrogen-DNA adduct ratios. In conclusion, plasma estrogen-DNA adduct ratio was associated with the presence of breast cancer or proliferating benign breast disease in premenopausal women in Taiwan.

PREVENTION RELEVANCE

This study provides evidence that endogenous estrogen-induced genotoxicity may contribute to the carcinogenesis of breast cancer in premenopausal Asian women. This work could have important preventive implication for the emerging disease in East Asia.

Efficient method for whole-breast irradiation therapy using Halcyon linear accelerators

Background

The Halcyon is a linear accelerator‐based treatment machine designed for a high‐throughput simplified workflow. The machine features a compact jawless design, dual‐layer multileaf collimators, and a single 6‐MV flattening filter‐free (FFF) beam. However, the machine's 6‐MV FFF beam may restrict its applicability to conventional techniques, such as field‐in‐field (FiF) radiotherapy, for breast cancer treatment. This study developed a practical and efficient hybrid method for imaging, planning, and irradiation procedures for whole‐breast irradiation using Halcyon linear accelerators.

Materials and methods

The proposed method involves five major steps: (1) field arrangement, (2) planning target volume (PTV) generation and evaluation, (3) basal plan generation, (4) inverse planning intensity–modulated radiation therapy plan generation, and (5) plan evaluation and irradiation. The PTV is generated using isodose curves plotted on the basis of tangential fields, which are applied to create a basal plan. Subsequently, a basal‐dose‐compensation approach is applied to further optimize the treatment plan. This efficient workflow necessitates executing only one onboard cone‐beam computed tomography procedure. This study included 10 patients with early‐stage breast cancer who were treated at our center. The performance of the proposed method was evaluated by comparing its corresponding irradiation time and dose statistics with those derived for a dynamically flattened beam‐based FiF (DFB‐FiF) method.

Results

All plans were normalized to ensure that 98% of the prescribed dose covered 95% of the PTV. On average, the global maximum doses in the proposed and DFB‐FiF methods were lower than 106%. The homogeneity index for right‐sided (left‐sided) breast cancer was 0.053 (0.056) in the proposed method and 0.073 (0.076) in the DFB‐FiF method. The dose statistics of normal tissues, including the contralateral breast, heart, and lungs, were comparable between the methods. However, the irradiation time per monitor unit in the proposed method was approximately five times faster than that in the DFB‐FiF method, but the planning time and complexity were similar between the methods.

Conclusions

This study developed and evaluated an efficient and practical hybrid method for whole‐breast irradiation using the Halcyon. This method can significantly reduce the irradiation time, while providing comparable dose statistics to the DFB‐FiF method.

Comprehensive profiles and diagnostic value of menopausal-specific gut microbiota in premenopausal breast cancer

In Western countries, breast cancer tends to occur in older postmenopausal women. However, in Asian countries, the proportion of younger premenopausal breast cancer patients is increasing. Increasing evidence suggests that the gut microbiota plays a critical role in breast cancer. However, studies on the gut microbiota in the context of breast cancer have mainly focused on postmenopausal breast cancer. Little is known about the gut microbiota in the context of premenopausal breast cancer. This study aimed to comprehensively explore the gut microbial profiles, diagnostic value, and functional pathways in premenopausal breast cancer patients. Here, we analyzed 267 breast cancer patients with different menopausal statuses and age-matched female controls. The α-diversity was significantly reduced in premenopausal breast cancer patients, and the β-diversity differed significantly between breast cancer patients and controls. By performing multiple analyses and classification, 14 microbial markers were identified in the different menopausal statuses of breast cancer. Bacteroides fragilis was specifically found in young women of premenopausal statuses and Klebsiella pneumoniae in older women of postmenopausal statuses. In addition, menopausal-specific microbial markers could exhibit excellent discriminatory ability in distinguishing breast cancer patients from controls. Finally, the functional pathways differed between breast cancer patients and controls. Our findings provide the first evidence that the gut microbiota in premenopausal breast cancer patients differs from that in postmenopausal breast cancer patients and shed light on menopausal-specific microbial markers for diagnosis and investigation, ultimately providing a noninvasive approach for breast cancer detection and a novel strategy for preventing premenopausal breast cancer.

Adherence to the DASH Diet and Risk of Breast Cancer

BACKGROUND

The Dietary Approach to Stop Hypertension (DASH) eating pattern has been recommended as a healthy dietary plan by several international guidelines. However, data on the association between the DASH diet and breast cancer is limited. This study investigated the association between the DASH dietary pattern and risk of breast cancer.

MATERIALS AND METHODS

This is a hospital-based case-control study conducted between 2014 and 2016 in the Cancer Institute of Iran. Patients with histopathologically confirmed breast cancer were recruited. Controls were healthy subjects who were frequency matched to cases by residential place and age (±10 years). A validated 168-item Food Frequency Questionnaire was applied to assess the dietary intake of participants. Physical activity was assessed using the Global Physical Activity Questionnaire. The DASH dietary pattern scores were calculated using the method introduced by Fung. Unconditional logistic regression, in which potential confounders were taken into account, was applied to determine the association between adherence to the DASH dietary pattern and odds of breast cancer.

RESULTS

The study participants comprised 477 patients with breast cancer and 507 healthy controls. In the total population, patients with breast cancer were slightly older (45.9 vs. 43.9 years, P = .02), had slightly higher BMI (21.9 vs. 20.2, P = .01) and were less physically active (20 vs. 27 MET h/wk. P < .01) than controls. In Model A, which was adjusted for age and energy intake, adherence to the DASH dietary pattern substantially reduced breast cancer risk in the total population (OR for comparing extreme tertiles: 0.62; 95% CI 0.44-0.78; P_trend = 0.004). Even after controlling for more cofounders, greatest adherence to DASH diet was associated with a 34% reduction in risk of breast cancer (OR 0.66; 95% CI 0.46, 0.94; P_trend = 0.03). In premenopausal women, adherence to the DASH dietary pattern was insignificantly associated with a 32% reduction in breast cancer risk. This risk reduction was 38% in postmenopausal women, which was also not found to be significant CONCLUSION: Adherence to the DASH dietary pattern could be associated with an approximately 30% reduction in risk of breast cancer. However, further studies, in particular studies with prospective design, are required to confirm this claim.

First-line Treatment with Ribociclib plus Endocrine Therapy for Premenopausal Women with Hormone-receptor-positive Advanced Breast Cancer: A Cost-effectiveness Analysis

BACKGROUND

We conducted a cost-effectiveness analysis incorporating recent phase III clinical trial (MONALEESA-7) data to evaluate the cost-effectiveness of ribociclib (RIB) as a first-line treatment for premenopausal women with hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer (ABC) from the United States healthcare payer perspective. In addition, because RIB has not been marketed in China, we identified the range of drug costs for which RIB could be considered cost effective from a Chinese healthcare system perspective.

PATIENTS AND METHODS

A Markov model was developed to evaluate the cost-effectiveness of adding RIB to endocrine therapy over a lifetime. The clinical outcomes and utility data were obtained from published literature. Costs data were obtained from United States and Chinese official websites, and we determined the potential price for RIB in China based on its price in the United States. The main outcomes of this study were the incremental cost-effectiveness ratio (ICER) and quality-adjusted life-years (QALYs).

RESULTS

The model projected that mean outcome was better with RIB and endocrine combined (3.83366 QALYs) than with endocrine therapy alone (2.71203 QALYs). In the United States, RIB and endocrine therapy cost an additional $604,960.06, resulting in an ICER of $539,357.95/QALY compared with endocrine monotherapy. Subgroup analyses indicated that, in China, the projected mean outcomes were better for RIB and endocrine therapy (6.37 QALYs) than for endocrine monotherapy (2.71 QALYs). The corresponding incremental costs were $224,731.88943. Thus, the ICER comparing RIB and endocrine therapy with endocrine therapy alone represented a $61,454.96/QALY gain.

CONCLUSION

Additional use of RIB is estimated to not be cost effective as a first-line treatment for premenopausal women with HR-positive, HER2-negative ABC in the United States. A value-based price for the cost of RIB is less than $31.74/200 mg for China.

Pharmacogenetics of tamoxifen therapy in Asian populations: from genetic polymorphism to clinical outcomes

BACKGROUND

Compared with western countries, Asian breast cancer patients have unique pathological and biological characteristics. Most of them are premenopausal women with HR positive. Tamoxifen as the first-line drug for premenopausal women with HR+ is involved in multiple enzymes and transporters during metabolizing and transporting process. Variants that cause decreased or inactive gene products leading to abnormal responses in tamoxifen therapy have well been studied in western countries, whereas such information is much less reported in Asian populations.

OBJECTIVE

In order to elucidate the relationship between genetic variants and tamoxifen-induced individual drug reactions in different Asian populations and further identify genotypes/phenotypes with potential therapeutic significance.

METHODS

We reviewed the frequencies of genetic variants in major enzymes and transporter genes involved in the metabolism and transport of tamoxifen across Asian populations as well as significant correlations between genotypes/metabolic phenotypes and metabolites concentrations or BC clinical outcomes.

RESULTS

Significant inter-ethnic differences in allele frequencies was found among Asian populations, such as CYP2D6*4, *10, *41, CYP2C9*2, ABCB1 C3435T and SLCO1B1*5, and CYP2D6*10/*10 is the most common genotype correlated with adverse clinical outcomes. Moreover, we summarized the barriers and controversies of implementing pharmacogenetics in tamoxifen therapy and concluded that more population-specific pharmacogenetic studies are needed in the future.

CONCLUSION

This review revealed more systematic pharmacogenomics of genes involved in the metabolism and transport besides CYP2D6, are required to optimize the genotyping strategies and guide the personalized tamoxifen therapy in Asian populations.

Obesity and Energy Balance Considerations in Triple-Negative Breast Cancer

ABSTRACT

Obesity is an increasingly prevalent state of energy imbalance that contributes to breast cancer risk and outcomes. The effects of obesity differ by breast cancer subtype and menopause. While most studies have focused on postmenopausal hormone receptor-positive disease, less is known about the relationship between obesity and triple-negative breast cancer (TNBC). Here we will review the observations linking obesity to TNBC, the socioeconomic disparities that contribute to obesity-related TNBC, and putative biologic mechanisms. Finally, we will consider the impact of obesity on surgical and medical treatment of TNBC and novel strategies to improve energy balance after cancer diagnosis.

Validation of Clinical Treatment Score post-5 years (CTS5) risk stratification in premenopausal breast cancer patients and Ki-67 labelling index

This study aimed to validate the Clinical Treatment Score post-5 years (CTS5)-based risk stratification in a cohort comprising pre- and postmenopausal patients with estrogen receptor (ER)–positive breast cancer. We investigated the clinicopathologic parameters including Ki-67 labelling index (LI) to identify factors affecting late distant recurrence (DR). Women with ER-positive breast cancer who were free of DR for 5 years were identified between January 2004 and December 2009. We investigated the risk of late DR (5–10 years) according to the CTS5 risk group. Cox regression analysis was used to determine the prognostic performance of CTS5 and identify factors associated with late DR. In all, 680 women were included. Of these, 379 (55.7%) were premenopausal and 301 (44.3%) were postmenopausal. At a median follow-up of 118 months, 32 women had late DR. CTS5 was a significant prognostic factor for late DR in both pre- and postmenopausal women. In the low CTS5 group, high Ki-67 LI (> 20%) was a significant risk factor for late DR. CTS5 is a useful tool for assessing the risk of late DR in pre- and postmenopausal women with ER-positive breast cancer. Extended endocrine therapy can be considered in patients with high Ki-67 LI (> 20%) in the low CTS5 group.

A case-control study of perfluoroalkyl substances and the risk of breast cancer in Taiwanese women

Breast cancer (BC) is a common cancer in women worldwide; however, the incidence of BC is increasing in younger women, possibly associated with the environment. Perfluoroalkyl substances (PFAS) are one of endocrine disruptors that accumulate in environment and impact human health. This study aimed to investigate whether the PFAS and BC are associated. We enrolled 120 BCE patients and 119 controls at National Taiwan University Hospital (NTUH) and also collected bio-specimen and questionnaire from 2013 to 2015. All subjects' plasma PFAS levels were analyzed by ultra-performance liquid chromatography tandem mass spectrometry method with electrospray ionization (UHPLC-ESI-MS/MS). A logistic regression model was used to estimate the association between PFAS and BC. In the ≤50 years age group, the adjusted odds ratio (OR) was 2.34 (95% CI = 1.02, 5.38) for perfluorooctane sulfonate (PFOS) exposure per natural log unit increase. After stratifying the estrogen receptor (ER) status and age group, we obtained a positive association for PFHxS and PFOS concentrations with respect to the risk of ER positive tumors for ≤50 years age group. In conclusion, we found that PFAS were associated with the BC risk of ER positive tumors in young Taiwanese women. Further studies are needed to follow and explore whether these associations are causal.

Impacts of Intralipid on Nanodrug Abraxane Therapy and on the Innate Immune System

A major obstacle to nanodrugs-mediated cancer therapy is their rapid uptake by the reticuloendothelial system that decreases the systemic exposure of the nanodrugs to tumors and also increases toxicities. Intralipid has been shown to reduce nano-oxaliplatin-mediated toxicity while improving bioavailability. Here, we have found that Intralipid reduces the cytotoxicity of paclitaxel for human monocytic cells, but not for breast, lung, or pancreatic cancer cells. Intralipid also promotes the polarization of macrophages to the anti-cancer M1-like phenotype. Using a xenograft breast cancer mouse model, we have found that Intralipid pre-treatment significantly increases the amount of paclitaxel reaching the tumor and promotes tumor apoptosis. The combination of Intralipid with half the standard clinical dose of Abraxane reduces the tumor growth rate as effectively as the standard clinical dose. Our findings suggest that pre-treatment of Intralipid has the potential to be a powerful agent to enhance the tumor cytotoxic effects of Abraxane and to reduce its off-target toxicities.

Adherence to the American Cancer Society Guidelines for Cancer Survivors and Health-Related Quality of Life among Breast Cancer Survivors

The development and validation of guidelines for breast cancer survivors are of importance due to the increased survival rate for breast cancer. In this cross-sectional study, we aimed to examine the association between adherence to the American Cancer Society (ACS) guidelines for cancer survivors and health-related quality of life (HRQoL). A total of 618 breast cancer survivors aged 30 to 81 years who had been diagnosed with stage I to III primary breast cancer and had surgery at least a year before enrollment were included. The participants completed the 36 Item Short-Form Health Survey (SF-36) to evaluate HRQoL, and adherence scores were calculated based on the Nutrition and Physical Activity Guidelines for Cancer Survivors, which were released by the ACS. Increasing adherence scores were associated with increasing scores on the physical component summary (PCS) and the physical functioning (PF), bodily pain (BP), and vitality (VT) domains (p for trend <0.001 for PCS and PF, 0.01 for BP, and 0.02 for VT); these scores were mainly driven by the associations among survivors with stage II–III cancer. Further prospective studies are needed to evaluate whether adherence to these guidelines improves HRQoL scores among breast cancer survivors.

Treating HR+/HER2- breast cancer in premenopausal Asian women: Asian Breast Cancer Cooperative Group 2019 Consensus and position on ovarian suppression

PURPOSE

Breast cancer in young Asian women has distinctive clinicopathological characteristics; hence, we question the universal generalizability of treatment recommendations based on data from predominantly non-Asian postmenopausal women.

METHODS

The Asian Breast Cancer Cooperative Group (ABCCG) reviewed current ESO-ESMO and St. Gallen recommendations for treating hormone receptor positive/human epidermal growth factor receptor 2 negative (HR+/HER2-) breast cancer in premenopausal women. Points disputed by ≥ 3/12 members were discussed, and statements on contentious issues formulated for anonymous voting; consensus required a ≥ 75% majority.

RESULTS

The ABCCG contends that: (1) Trials in premenopausal women are not only necessary, but also worthwhile if performed separately from others that also enroll postmenopausal participants. (2) Not all premenopausal women with HR+ early breast cancer need adjuvant ovarian function suppression (OFS). (3) Certain clinical factors might influence decision-making about prescribing OFS. (4) For early HR+/HER2- breast cancer in premenopausal patients with OFS, tamoxifen is preferred for intermediate-risk cases; for high risk, near-consensus supported aromatase inhibitor, despite no clear overall survival benefit versus tamoxifen. (5) Oncotype DX Breast Recurrence Score® has different treatment implications in patients aged ≤ 50 versus > 50 years. (6) High-risk patients (if premenopausal after chemotherapy) should receive adjuvant chemotherapy and OFS plus aromatase inhibitor. (7) For patients with advanced disease receiving OFS on a backbone of tamoxifen, gonadotrophin-releasing hormone agonists may be given 12-weekly. (8) For premenopausal women who decline OFS or oophorectomy, tamoxifen alone is still an option but is considered less effective; other monotherapies are also less effective than OFS plus such treatments.

CONCLUSION

Premenopausal Asian women with breast cancer have unique disease characteristics and may benefit from treatment that differs somewhat from international guidelines. Given the great diversity of patients and clinical settings worldwide, the ABCCG advocates evidence-based yet flexible and individualized use of all potential options to improve breast cancer outcomes.

Albumin and hemoglobin adducts of estrogen quinone as biomarkers for early detection of breast cancer

Cumulative estrogen concentration is an important determinant of the risk of developing breast cancer. Estrogen carcinogenesis is attributed to the combination of receptor-driven mitogenesis and DNA damage induced by quinonoid metabolites of estrogen. The present study was focused on developing an improved breast cancer prediction model using estrogen quinone-protein adduct concentrations. Blood samples from 152 breast cancer patients and 71 healthy women were collected, and albumin (Alb) and hemoglobin (Hb) adducts of estrogen-3,4-quinone and estrogen-2,3-quinone were extracted and evaluated as potential biomarkers of breast cancer. A multilayer perceptron (MLP) was used as the predictor model and the resultant prediction of breast cancer was more accurate than other existing detection methods. A MLP using the logarithm of the concentrations of the estrogen quinone-derived adducts (four input nodes, 10 hidden nodes, and one output node) was used to predict breast cancer risk with accuracy close to 100% and area under curve (AUC) close to one. The AUC value of one showed that both data sets were separable. We conclude that Alb and Hb adducts of estrogen quinones are promising biomarkers for the early detection of breast cancer.

Comprehensive integrated analysis of gene expression datasets identifies key anti-cancer targets in different stages of breast cancer

Breast cancer is one of the primary threats to women's health worldwide. However, the molecular mechanisms underlying the development of breast cancer remain to be fully elucidated. The present study aimed to investigate specific target gene expression profiles in breast cancer tissues in general and in different breast cancer stages, as well as to explore their functions in tumor development. For integrated analysis, a total of 5 gene expression profiling datasets for 3 different stages of breast cancer (stages I-III) were downloaded from the Gene Expression Omnibus of the National Center for Biotechnology Information. Pre-processing of these datasets was performed using the Robust Multi-array Average algorithm and global renormalization was performed for all studies. Differentially expressed genes between breast cancer patients and controls were estimated using the empirical Bayes algorithm. The Database for Annotation, Visualization and Integrated Discovery web server was used for analyzing the enrichment of the differentially expressed genes in Gene Ontology terms of the category biological process and in Kyoto Encyclopedia of Genes and Genomes pathways. Furthermore, breast cancer target genes were downloaded from the Thomson Reuters Integrity Database. We merged these target genes with the genes in breast cancer datasets. Analysis of anti-breast cancer gene networks was performed using the Genome-scale Integrated Analysis of Gene Networks in Tissues web server. The results demonstrated that the normal functions of the cell cycle, cell migration and cell adhesion were altered in all stages of breast cancer. Furthermore, 12 anti-breast cancer genes were identified to be dysregulated in at least one of the three stages. Among all of these genes, ribonucleotide reductase regulatory subunit M2 (RRM2) exhibited the highest degree of interaction with other interacting genes. Analysis of the network interactions revealed that the transcription factor of RRM2 is crucial for cancer development. Other genes, including mucin 1, progesterone receptor and cyclin-dependent kinase 5 regulatory subunit associated protein 3, also exhibited a high degree of interaction with the associated genes. In conclusion, several key anti-breast cancer genes identified in the present study are mainly associated with the regulation of the cell cycle, cell migration, cell adhesion and other cancer-associated cell functions, particularly RRM2.

Adiposity, Inflammation, and Breast Cancer Pathogenesis in Asian Women

Obesity is associated with white adipose tissue (WAT) inflammation in the breast, elevated levels of the estrogen biosynthetic enzyme, aromatase, and systemic changes that predispose to breast cancer development. We examined whether WAT inflammation and its associated systemic effects correlate with body fat levels in an Asian population where body mass index (BMI) is not an accurate assessment of obesity and cancer risk. We also investigated whether biologic differences could account for the greater proportion of premenopausal estrogen receptor (ER)-positive breast cancer in Asian versus Western countries. Breast WAT and fasting blood were prospectively collected from Taiwanese women undergoing mastectomy for breast cancer treatment. Body composition was measured in a subgroup using bioelectrical impedance analysis. WAT inflammation was defined by the presence of crown-like structures of the breast, which are composed of dead or dying adipocytes surrounded by macrophages. Findings were compared with U.S. Caucasian women. In the Taiwanese cohort (n = 72), breast WAT inflammation was present in 31 (43%) women and was associated with elevated BMI (P < 0.01) and increased levels of body fat (P < 0.01), C-reactive protein (P = 0.02), triglycerides (P < 0.01), insulin resistance scores (P = 0.04), and lower HDL cholesterol (P < 0.01). ER+ tumors were associated with greater body fat versus other subtypes (P = 0.03). Compared with U.S. Caucasians (n = 267), Taiwanese women had larger breast adipocytes despite lower BMI after adjusting for BMI and menopausal status (P = 0.01). A subclinical inflammatory state associated with increased adiposity and metabolic dysfunction could contribute to breast cancer pathogenesis in Asian women. Cancer Prev Res; 11(4); 227-36. ©2017 AACR.

Acridone suppresses the proliferation of human breast cancer cells in vitro via ATP-binding cassette subfamily G member 2

In the past decades, the tricyclic acridone ring system has become a focus of major research by medicinal chemists due to the biological significance of this moiety in drug design and discovery. Acridone has substantial bio-potential since it performs crucial functions, including antibacterial, antimalarial, antiviral and anti-neoplastic activities. However, the anticancer effect and the underlying mechanisms of acridone on breast cancer cells remains unclear. In the present study, the anti-tumor function and the underlying mechanisms of acridone were evaluated in vitro. Firstly, an MTT assay was used to evaluate the inhibitory effect of acridone. Subsequently, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to investigate whether ATP binding cassette subfamily G member 2 (ABCG2) was associated with the function of acridone. Finally, western blotting was used to confirm the results of RT-qPCR. The present study demonstrated that acridone may decrease the proliferation of MDA-MB-231 cells dose-dependently. Further experiments revealed that acridone may downregulate the mRNA and protein expression levels of ABCG2, supporting the potential application of acridone in breast cancer treatment. These findings suggested that acridone is a potential agent in the treatment of human breast cancer.

Overexpression of phosphoprotein phosphatase 2A predicts worse prognosis in patients with breast cancer: a 15-year follow-up

Breast cancer subtypes can be stratified by IHC expression of estrogen receptor, progesterone receptor, and human epidermal growth factor 2 (HER2). The signaling pathways mediated by these receptors are the dominant drivers of cell proliferation and survival in most human breast cancers. One of the most frequently overactivated pathways in breast cancer is the AKT signaling cascade. Protein phosphatase 2A (PP2A) acts as a switch to turn off signal transduction in the AKT pathway; however, it is frequently inactivated in many cancers by phosphorylation of Tyr-307 to form phosphoprotein phosphatase 2A (p-PP2A). This study aimed to investigate the clinical significance of p-PP2A and phospho-AKT (p-AKT) expression in 672 patients with breast cancer during a 15-year follow-up. The breast tissue microarray was evaluated for p-PP2A and p-AKT expression using IHC staining and scores. Analysis of IHC staining results revealed that p-PP2A expression was positively correlated with HER2, Ki-67, and p-AKT overexpression (P<.001, P=.003, and P=.001, respectively). At the time of diagnosis, breast cancer patients with higher p-PP2A expression had significantly shorter 15-year OS than patients with lower p-PP2A expression did (P=.017). Multivariate Cox regression analysis revealed that high p-PP2A expression was an independent prognostic factor for shorter OS (hazard ratio, 1.741; P=.012). Our data revealed that high p-PP2A expression is positively associated with HER2, Ki-67, and p-AKT expression. High p-PP2A expression correlates with poor clinical outcomes in breast cancer, especially in patients with TNBC.

Polymorphisms of ESR1, UGT1A1, HCN1, MAP3K1 and CYP2B6 are associated with the prognosis of hormone receptor-positive early breast cancer

In this study, we investigated whether single nucleotide polymorphisms (SNPs) identified by genome-wide association study (GWAS) (MAP3K1, FGFR2, TNRC9, HCN1, and 5p12), and SNPs involved in the metabolism of estrogen (CYP19, COMT, ESR1, and UGT1A1), tamoxifen (CYP2C9, CYP2C19, CYP3A5, and CYP2D6), and chemotherapeutic agents (ABCB1, ALDH3A1, and CYP2B6) are associated with the prognoses of 414 hormone receptor (HR)-positive early breast cancers with negative or 1 to 3 nodal metastases. At a median follow-up period of 10.6 years, 363 patients were alive, and 51 (12.3%) had died. Multiple-adjusted hazard ratios (aHRs) and the corresponding 95% confidence intervals for distant disease-free survival (DDFS), disease-free survival (DFS), and overall survival (OS) in association with the genotypes of 34 SNPs from the above-mentioned 16 genes were evaluated, using the stepwise selection Cox model. We found that the SNP, ESR1-codon325 rs1801132 (G/G+G/C), was associated with a longer DDFS, whereas UGT1A1 rs4148323 (A/A+A/G), and HCN1 rs981782 (A/A+A/C) were significantly associated with poorer DDFS. MAP3K1 rs889312 (C/C) and CYP2B6 rs3211371 (T/C) were significantly associated with poor DFS, DDFS and OS. Among premenopausal women, MAP3K1 rs889312 (C/C), CYP2B6 rs3211371 (T/C), CYP2B6 rs4802101 (T/T), ABCB1 rs2032582 (C/C), and ALDH3A1 rs2231142 (G/G) were significantly associated with poor DDFS, DFS, or OS. Our results provide additional evidence that genetic polymorphisms observed in SNPs are associated with the prognoses of patients with HR-positive breast cancers; this may indicate different treatment strategies for these patients.

A polygenic risk score for breast cancer risk in a Taiwanese population

BACKGROUND

Multiple common variants identified by genome-wide association studies showed limited evidence of the risk of breast cancer in Taiwan. In this study, we analyzed the breast cancer risk in relation to 13 individual single-nucleotide polymorphisms (SNPs) identified by a GWAS in an Asian population.

METHODS

In total, 446 breast cancer patients and 514 healthy controls were recruited for this case-control study. In addition, we developed a polygenic risk score (PRS) including those variants significantly associated with breast cancer risk, and also evaluated the contribution of PRS and clinical risk factors to breast cancer using receiver operating characteristic curve (AUC).

RESULTS

Logistic regression results showed that nine individual SNPs were significantly associated with breast cancer risk after multiple testing. Among all SNPs, six variants, namely FGFR2 (rs2981582), HCN1 (rs981782), MAP3K1 (rs889312), TOX3 (rs3803662), ZNF365 (rs10822013), and RAD51B (rs3784099), were selected to create PRS model. A dose-response association was observed between breast cancer risk and the PRS. Women in the highest quartile of PRS had a significantly increased risk compared to women in the lowest quartile (odds ratio 2.26; 95% confidence interval 1.51-3.38). The AUC for a model which contained the PRS in addition to clinical risk factors was 66.52%, whereas that for a model which with established risk factors only was 63.38%.

CONCLUSIONS

Our data identified a genetic risk predictor of breast cancer in Taiwanese population and suggest that risk models including PRS and clinical risk factors are useful in discriminating women at high risk of breast cancer from those at low risk.

Breast cancer in Mongolia: an increasingly important health policy issue

Breast cancer is a leading cause of cancer-related death for women in both developed and developing countries. The incidence and mortality of breast cancer in Mongolia, while low compared with other counties, has been increasing on an annual basis. In addition, in Mongolia, approximately 90% of the patients are diagnosed at a late stage, resulting in high mortality, with the majority of individuals diagnosed with breast cancer dying within 5 years of diagnosis. Breast cancer screening plays an important role in reducing mortality in Western countries and has been adopted by a number of Asian countries; however, no such approach exists in Mongolia. In a country of limited resources, implementation of expensive health strategies such as screening requires effective allocations of resources and the identification of the most effective imaging methods. This requirement relies on recent accurate data; however, at this time, there is a paucity of information around breast cancer in Mongolia. Until data around features of the disease are available, effective strategies to diagnose breast cancer that recognize the economic climate in Mongolia cannot be implemented and the impact of breast cancer is likely to increase.

Human papillomavirus infection and risk of breast cancer: a meta-analysis of case-control studies

Background

Although systematic reviews (SR) report that human papillomavirus (HPV) increases the risk of breast cancer, there are still disputes regarding this association. In particular, it has been argued that the risk level differs depending on nationality, type of tissue, subtype of HPV, and publication year. Considering that the searching year of publication for the previous SRs was June 2013, a renewal meta-analysis needs to be conducted.

Methods

Using articles selected in the previous SRs, we compiled a list of references, cited articles, and related articles from the PubMed and Scopus databases. Of these, only publications with data from case-control studies on HPV DNA-positivity in tissues were chosen. Summary odds ratio (SOR) and 95 % confidence interval (CI) were calculated through meta-analysis. Meta-regression analysis was performed for nationality, types of tissue, subtype of HPV, and publication year.

Results

Twenty-two case-control studies were selected, and the total number of individuals in the case and control group was 1897 and 948, respectively. According to the meta-analysis about the 22 publications, HPV infection increased the risk of breast cancer (SOR = 4.02, 95 % CI: 2.42–6.68; I-squared = 44.7 %). Statistical significance was not found in meta-regression performed on the four variables of nationality, type of tissue, subtype of HPV, and publication year which some researchers think sources of heterogeneity.

Conclusions

The results of the present study supported the argument that HPV infection increases the risk of breast cancer. Age-matched case-control studies are in need in the future.

Tamoxifen induces apoptosis through cancerous inhibitor of protein phosphatase 2A-dependent phospho-Akt inactivation in estrogen receptor-negative human breast cancer cells

Introduction

Tamoxifen, a selective estrogen receptor (ER) modulator, may affect cancer cell survival through mechanisms other than ER antagonism. In the present study, we tested the efficacy of tamoxifen in a panel of ER-negative breast cancer cell lines and examined the drug mechanism.

Methods

In total, five ER-negative breast cancer cell lines (HCC-1937, MDA-MB-231, MDA-MB-468, MDA-MB-453 and SK-BR-3) were used for in vitro studies. Cellular apoptosis was examined by flow cytometry and Western blot analysis. Signal transduction pathways in cells were assessed by Western blot analysis. The in vivo efficacy of tamoxifen was tested in xenograft nude mice.

Results

Tamoxifen induced significant apoptosis in MDA-MB-231, MDA-MB-468, MDA-MB-453 and SK-BR-3 cells, but not in HCC-1937 cells. Tamoxifen-induced apoptosis was associated with inhibition of cancerous inhibitor of protein phosphatase 2A (CIP2A) and phospho-Akt (p-Akt) in a dose-dependent manner. Ectopic expression of either CIP2A or Akt protected MDA-MB-231 cells from tamoxifen-induced apoptosis. In addition, tamoxifen increased protein phosphatase 2A (PP2A) activity, and tamoxifen-induced apoptosis was attenuated by the PP2A antagonist okadaic acid in the sensitive cell lines, but not in resistant HCC-1937 cells. Moreover, silencing CIP2A by small interfering RNA sensitized HCC-1937 cells to tamoxifen-induced apoptosis. Furthermore, tamoxifen regulated CIP2A protein expression by downregulating CIP2A mRNA. Importantly, tamoxifen inhibited the in vivo growth of MDA-MB-468 xenograft tumors in association with CIP2A downregulation, whereas tamoxifen had no significant effect on CIP2A expression and anti-tumor growth in HCC-1937 tumors.

Conclusions

Inhibition of CIP2A determines the effects of tamoxifen-induced apoptosis in ER-negative breast cancer cells. Our data suggest a novel “off-target“ mechanism of tamoxifen and suggest that CIP2A/PP2A/p-Akt signaling may be a feasible anti-cancer pathway.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-014-0431-9) contains supplementary material, which is available to authorized users.

Higher incidence of premenopausal breast cancer in less developed countries; myth or truth?

Background

Fundamental etiologic differences have been suggested to cause earlier onset of breast cancer in less developed countries (LDCs) than in more developed countries (MDCs). We explored this hypothesis using world-wide breast cancer incidence data.

Methods

We compared international age-standardized incidence rates (ASR) of pre- (<50 years) and postmenopausal (≥50 years) breast cancers as well as temporal trends in ASRs of pre-and postmenopausal breast cancer among selected countries during 1975–2008. We used joinpoint log-linear regression analysis to estimate annual percent changes (APC) for premenopausal and postmenopausal breast cancer in the northern Europe and in Black and White women population in the US.

Results

Premenopausal breast cancers comprised a substantially higher proportion of all incident breast cancers in LDCs (average 47.3%) compared to MDCs (average 18.5%). However, the ASR of premenopausal breast cancer was consistently higher in MDCs (29.4/100,000) than LDCs (12.8/100,000). The ASR of postmenopausal cancer was about five-fold higher in the MDCs (307.6/100,000) than the LDCs (65.4/100,000). The APC of breast cancer in Denmark was substantially higher in postmenopausal (1.33%) than premenopausal cancer (0.98%). Higher incidence of breast cancer among the white than black women in the US was pertained only to the postmenopausal cancer.

Conclusion

The substantial and consistent lower age-specific incidence of breast cancer in LDCs than in MDCs contradicts the theory of earlier onset. Demographic differences with fewer old women in LDCs and lower prevalence of risk factors of postmenopausal cancer are the most likely explanation to the lower mean age at diagnosis in these countries.

Distinct clinicopathological features and prognosis of emerging young-female breast cancer in an East Asian country: a nationwide cancer registry-based study

BACKGROUND

A rapid surge of young-female breast cancer (YFBC) has been observed in Taiwan and other East Asian countries. We recently reported that these cases of YFBC, in contrast to their Western counterparts, are predominantly luminal A subtype. YFBC in Asia may have distinct clinicopathological features and outcomes.

METHODS

Data collected prospectively by participating hospitals were retrieved from the Taiwan Cancer Database. A total of 15,881 women with newly diagnosed stage I-III breast cancer in 2002-2006 were included. The age at diagnosis was categorized into nine 5-year groups (from <30 years to ≥65 years). Clinicopathological variables and patient disease-free survival (DFS) were compared by age group.

RESULTS

The rates of stage I, estrogen receptor-positive (ER+), and progesterone receptor-positive breast cancer were higher in the younger patients (<50 years) than in the older patients (≥50 years). Univariate analysis showed that the 40-44 and 45-49 age groups were significantly associated with longer DFS than the other age groups. In the ER+ subgroup, multivariate analysis consistently showed that the 40-44 age group was significantly associated with longer DFS than the other age groups except for the 45-49 age group. In contrast, multivariate analysis of the ER-negative subgroup revealed no significant difference of DFS between the 40-44 age group and other age groups.

CONCLUSION

Emerging YFBC in Taiwan is uniquely associated with favorable pathological features and better outcomes and should not be regarded as the mirror image of its Western counterpart.

Cumulative body burdens of polycyclic aromatic hydrocarbons associated with estrogen bioactivation in pregnant women: protein adducts as biomarkers of exposure

The objective of this research was to simultaneously analyze protein adducts of quinonoid metabolites of naphthalene and endogenous estrogen in serum albumin (Alb) derived from healthy pregnant women in Taiwan and to explore the correlations among them. The isomeric forms of cysteinyl adducts of naphthoquinones, including 1,2-naphthoquinone (1,2-NPQ) and 1,4-naphthoquinone (1,4-NPQ) as well as estrogen quinones, including estrogen-2,3-quinones (E2-2,3-Q) and estrogen-3,4-quinones (E2-3,4-Q), are characterized after adduct cleavage. Results showed that the median levels of cysteinyl adducts of 1,2-NPQ and 1,4-NPQ on serum albumin were 249-390 and 16.0-24.8 pmol g(-1), respectively. Logged levels of 1,2-NPQ-Alb were correlated with logged levels of 1,4-NPQ-Alb (correlation coefficient r = 0.551, P < 0.001). Cysteinyl adducts of E2-2,3-Q-1-S-Alb, E2-2,3-Q-4-S-Alb, and E2-3,4-Q-2-S-Alb were detected in all subjects with median levels at 275-435, 162-288, and 197-254 pmol g(-1), respectively. We also found a positive relationship between logged levels of E2-2,3-Q-4-S-Alb and those of E2-3,4-Q-2-S-Alb (r = 0.770, P < 0.001).We noticed that median levels of E2-2,3-Q-derived adducts (E2-2,3-Q-1-S-Alb plus E2-2,3-Q-4-S-Alb) in pregnant women were greater than those of E2-3,4-Q-2-S-Alb (∼2-3-fold). Taken together, this evidence lends further support to the theme that cumulative concentration of E2-3,4-Q is a significant predictor of the risk of breast cancer. Furthermore, we noticed that levels of 1,2-NPQ-Alb are positively associated with levels of E2-3,4-Q-2-S-Alb (r = 0.522, P < 0.001) and those of E2-2,3-Q-4-S-Alb (r = 0.484, P < 0.001). Overall, this evidence suggests that environmental exposure to polycyclic aromatic hydrocarbons may modulate estrogen homeostasis and enhance the production of reactive quinone species of endogenous estrogen in humans.

CYP19 genetic polymorphism haplotype AASA is associated with a poor prognosis in premenopausal women with lymph node-negative, hormone receptor-positive breast cancer

Given the critical role of CYP19 in estrogen synthesis, we investigated the influence of CYP19 gene polymorphisms on the clinical outcome of lymph node- (LN-) negative, hormone receptor- (HR-) positive early breast cancers. Genotyping for the CYP19 polymorphisms rs4646 (A/C), rs1065779 (A/C), CYP19 (TTTA)n (short allele/long (S/L) allele using the 7 TTTA repeat polymorphism as the cut-off), and rs1870050 (A/C) was performed on 296 patients with LN-negative, HR-positive breast cancers. All patients received adjuvant hormonal therapy. Associations were examined between these 4 genotypes and 6 common haplotypes of CYP19 and distant disease-free survival (DDFS), disease-free survival (DFS), and overall survival (OS). Patients were divided into the 6 subhaplotypes of CCLA (41.1%), AASA (17.1%), CASA (11.9%), CCLC (8.9%), CCSA (7.5%), AASC (8.9%), and others (4.6%). In premenopausal patients, haplotype AASA was significantly associated with a poor DDFS (adjusted hazard ratio (aHR), 3.3; P = 0.001), DFS (aHR, 2.5; P = 0.0008), and OS (aHR, 2.9; P = 0.0004) after adjusting for age, tumor size, tumor grade, estrogen receptor status, progesterone receptor status, chemotherapy, pathology, adjuvant hormone therapy, menopausal status, and radiotherapy. Furthermore, haplotype AASA remained a negative prognostic factor for premenopausal patients receiving adjuvant chemotherapy in terms of DDFS (aHR, 4.5; P = 0.0005), DFS (HR, 3.2; P = 0.003), and OS (HR, 6.4; P = 0.0009). However, in postmenopausal patients, haplotype AASA was not associated with a poor prognosis, whereas the AASC haplotype was significantly associated with a poor DFS (aHR, 3.1; P = 0.03) and OS (aHR, 4.4; P = 0.01). Our results indicate that, in patients with LN-negative, HR-positive breast cancers, genetic polymorphism haplotype AASA is associated with poor survival of premenopausal women but does not affect survival of postmenopausal women.

The dyslipidemia-associated SNP on the APOA1/C3/A5 gene cluster predicts post-surgery poor outcome in Taiwanese breast cancer patients: a 10-year follow-up study

Background

Post-surgery therapies are given to early-stage breast cancer patients due to the possibility of residual micrometastasis, and optimized by clincopathological parameters such as tumor stage, and hormone receptor/lymph node status. However, current efficacy of post-surgery therapies is unsatisfactory, and may be varied according to unidentified patient genetic factors. Increases of breast cancer occurrence and recurrence have been associated with dyslipidemia, which can attribute to other known risk factors of breast cancer including obesity, diabetes and metabolic syndrome. Thus we reasoned that dyslipidemia-associated nucleotide polymorphisms (SNPs) on the APOA1/C3/A5 gene cluster may predict breast cancer risk and tumor progression.

Methods

We analyzed the distribution of 5 selected APOA1/C3/A5 SNPs in recruited Taiwanese breast cancer patients (n=223) and healthy controls (n=162). The association of SNP (APOA1 rs670) showing correlation with breast cancer with baseline and follow-up parameters was further examined.

Results

APOA1 rs670 A allele carriage was higher in breast cancer patients than controls (59.64% vs. 48.77%, p=0.038). The rs670 A allele carrying patients showed less favorable baseline phenotype with positive lymph nodes (G/A: OR=3.32, 95% CI=1.77-6.20, p<0.001; A/A: OR=2.58, 95% CI=1.05-6.32, p=0.039) and negative hormone receptor expression (A/A: OR=4.85, 95%CI=1.83-12.83, p=0.001) in comparison to G/G carriers. Moreover, rs670 A/A carrying patients had higher risks in both tumor recurrence (HR=3.12, 95% CI=1.29-7.56, p=0.012) and mortality (HR=4.36, 95% CI=1.52-12.47, p=0.006) than patients with no A alleles after adjustments for associated baseline parameters. Furthermore, the prognostic effect of rs670 A/A carriage was most evident in lymph node-negative patients, conferring to the highest risks of recurrence (HR=4.98, 95% CI=1.40-17.70, p=0.013) and mortality (HR=9.87, 95%CI=1.60-60.81, p=0.014) than patients with no A alleles.

Conclusions

APOA1 rs670 A/A carriage showed poor post-surgery prognosis in Taiwanese lymph node-negative breast cancer patients, whose prognosis were considered better and adjuvant treatment might be less stringent according to currently available assessment protocols. Our findings suggest that APOA1 rs670 indicate a post-surgery risk of breast cancer disease progression, and that carriers of this SNP may benefit from more advanced disease monitoring and therapy regimens than the current regular standards. Furthermore, control of lipid homeostasis might protect APOA1 rs670 minor allele carriers from breast cancer occurrence and progression.

Angiotensin-converting enzyme inhibitors enhance the effect of cyclooxygenase inhibitors on breast cancer: a nationwide case-control study

OBJECTIVES

Angiotensin-converting enzyme (ACE) inhibitors are first-line antihypertensive and potential cancer preventive agents. Interest in breast cancer prevention is growing, and more clinical evidence is needed regarding the effects of preventive therapy, alone or in combination.

METHODS

This was a nationwide case-control analysis from the Taiwan National health Insurance Research Database. We analyzed 16,847 female breast cancer patients (diagnosed between 1 January 2002 and 31 December 2008) and 50,541 matched individuals. Longitudinal exposure to ACE inhibitors and cyclooxygenase inhibitors was compared.

RESULTS

The risk of developing breast cancer among patients taking both aspirin and an ACE inhibitor decreased as the ACE inhibitor dose increased. Among patients receiving between 28 and 364 cumulative defined daily doses (cDDDs) of aspirin, the adjusted odds ratios (ORs) were 0.97 (0.90-1.06), 0.91 (0.82-1.03), and 0.79 (0.68-0.92) for women taking ACE inhibitors for 0-27, 28-364, and more than 365 cDDD, respectively. Among women receiving more than 365 cDDD of aspirin, the adjusted ORs were 0.91 (0.80-1.03), 0.81 (0.70-0.94), and 0.81 (0.71-0.92) as the ACE inhibitor dose increased, respectively. Women taking nonaspirin NSAIDs along with an ACE inhibitor had the same finding. Among women taking 28-364 cDDD of NSAIDs, the adjusted ORs were 0.85 (0.81-0.89), 0.87 (0.81-0.94), and 0.80 (0.73-0.88); for women receiving more than 365 cDDD of NSAIDs, the adjusted ORs were 0.68 (0.62-0.74), 0.61 (0.53-0.70), and 0.60 (0.52-0.70) as the ACE inhibitor dose increased, respectively.

CONCLUSION

The findings of this nationwide analysis support the hypothesis that ACE inhibitors enhance the antitumor effect of cyclooxygenase inhibitors on breast cancer.

Ultrasound imaging evaluation of abdominal muscles after breast reconstruction with a unilateral pedicled transverse rectus abdominis myocutaneous flap

BACKGROUND

A muscle-sparing (MS) procedure using a full-width pedicled transverse rectus abdominis (RA) myocutaneous (TRAM) flap was developed to reduce abdominal morbidities after breast reconstruction. However, the effects of this procedure on the morphology of the remnant RA muscle and other abdominal muscles remain unclear.

OBJECTIVE

Ultrasound imaging was used to evaluate the morphology of the remnant RA muscle and other abdominal muscles in women with the MS pedicled TRAM flap procedure.

DESIGN

A case-control, cross-sectional design was used.

METHODS

Thirty-four women with an MS unilateral pedicled TRAM flap procedure after mastectomy (TRAM group) and 25 women who were healthy and matched for age (control group) participated. The curl-up test measured trunk flexor muscle strength. Ultrasound imaging measured the thickness of all abdominal muscles in all participants and the cross-sectional area of the RA muscle at rest and in an isometric position with the head raised in women in the TRAM group. Acoustic echogenicity and border visibility assessed the tissue composition of the remnant RA muscle.

RESULTS

Trunk flexor muscle strength was weaker in the TRAM group than in the control group. Compared with the remnant RA muscle in the contracted state, the remnant RA muscle in the relaxed state was thinner and had a smaller cross-sectional area. The remnant RA muscle in the relaxed state also was thinner, more echoic, and less visible than its contralateral counterpart. No differences in the thickness of the other abdominal muscles were found between the sides. The abdominal muscles in the TRAM group were smaller than those in the control group.

LIMITATION

Because a prospective, longitudinal design was not used, a definite cause-effect relationship could not be determined.

CONCLUSIONS

In women with an MS unilateral pedicled TRAM flap procedure, the remnant RA muscle retains its ability to change in size during contraction, albeit at reduced levels. Muscular atrophy occurs in other ipsilateral and contralateral abdominal muscles as well as the remnant RA muscle. Postoperative immobilization is the most likely cause of generalized weakness of the abdominal musculature.

Surface markers in stem cells and cancer from the perspective of glycomic analysis

Most cancers are detected when patients present with symptoms, and at that point the disease is usually quite advanced and often not curable. Therefore, new biomarkers are needed for detection and therapy. The recent success of using monoclonal antibodies against nonprotein gangliosides for the treatment of high-risk neuroblastoma provides an incentive to search for new glycan-targeted immunotherapies for cancer using markers found through glycomic analysis as targets. Since more than 85% of cell surface components are glycosylated, glycomic analysis is useful to probe systematically the cancer cell surface, in search for novel glycoproteins and glycolipids. Furthermore, cancer cells tend to dedifferentiate and express many oncofetoproteins, since human embryonic stem cells (ESCs) are derived from epiblast of embryo, representing the early stage of normal embryonic development before gastrulation. Unique ESC surface markers are likely to be found in cancer cells, but not in normal mature tissues. Moreover, stem cells and cancer cells share several common features in related regulatory mechanisms and signaling pathways. Thus, identification of the cancer stem cells in cancer and definition of the glycoproteomic changes that accompany their transformation are important for the development of strategies for early detection and treatment of cancer.

Postmenopausal breast cancer in Iran; risk factors and their population attributable fractions

BACKGROUND

Causes of the rapidly increasing incidence of breast cancer in Middle East and Asian countries are incompletely understood. We evaluated risk factors for postmenopausal breast cancer and estimated their attributable fraction in Iran.

METHODS

We performed a hospital-based case-control study, including 493 women, diagnosed with breast cancer at 50 years or later between 2005-2008, and 493 controls. We used logistic regression models to estimate multivariable odds ratios (OR) and 95% confidence intervals (CI), and population attributable fractions (PAF) for significant risk factors.

RESULTS

The risk of breast cancer decreased with increasing parity. Compared with nulliparous women, the adjusted OR (95% CI) was 0.53 (0.25-1.15) for parity 1-3, 0.47 (0.29-0.93) for parity 4-6 and 0.23 (0.11-0.50) for parity ≥ 7. The estimated PAF for parity (<7) was 52%. The positive association between body mass index (BMI) and breast cancer risk was confined to women diagnosed at 58 years or later. Compared with normal weight women (BMI 18.5-24.9), overweight (BMI 25-29.9) and obese (BMI ≥ 30) women were at increased risk of breast cancer diagnosed at 58 years or later (ORs [95% CI] 1.27 [0.97-2.65] and 2.34 [1.33-4.14], respectively). The estimated PAF for obesity/overweight (BMI >25) was approximately 25%. The family history was significantly associated with increased breast cancer risk, but not increasing height, early age at menarche, late age at first birth or short breastfeeding.

CONCLUSIONS

Decreasing parity and increasing obesity are determinants of increasing breast cancer incidence among Iranian women. These trends predict a continuing upward trend of postmenopausal breast cancer.

Association between chronic viral hepatitis infection and breast cancer risk: a nationwide population-based case-control study

Background

In Taiwan, there is a high incidence of breast cancer and a high prevalence of viral hepatitis. In this case-control study, we used a population-based insurance dataset to evaluate whether breast cancer in women is associated with chronic viral hepatitis infection.

Methods

From the claims data, we identified 1,958 patients with newly diagnosed breast cancer during the period 2000-2008. A randomly selected, age-matched cohort of 7,832 subjects without cancer was selected for comparison. Multivariable logistic regression models were constructed to calculate odds ratios of breast cancer associated with viral hepatitis after adjustment for age, residential area, occupation, urbanization, and income. The age-specific (<50 years and ≥50 years) risk of breast cancer was also evaluated.

Results

There were no significant differences in the prevalence of hepatitis C virus (HCV) infection, hepatitis B virus (HBV), or the prevalence of combined HBC/HBV infection between breast cancer patients and control subjects (p = 0.48). Multivariable logistic regression analysis, however, revealed that age <50 years was associated with a 2-fold greater risk of developing breast cancer (OR = 2.03, 95% CI = 1.23-3.34).

Conclusions

HCV infection, but not HBV infection, appears to be associated with early onset risk of breast cancer in areas endemic for HCV and HBV. This finding needs to be replicated in further studies.

Breast cancer in Hong Kong, Southern China: the first population-based analysis of epidemiological characteristics, stage-specific, cancer-specific, and disease-free survival in breast cancer patients: 1997-2001

Background

Cancer registries have been set up worldwide to provide information for cancer health planning. There are known variations in breast cancer incidence and mortality worldwide. However, breast cancer incidence, pathological characteristics, and survival data is still under-reported in Asian countries. This is the first comprehensive population-based breast cancer study performed using population database of the Hong Kong Cancer Registry.

Methods

A retrospective review of medical records of 8,961 subjects who were diagnosed with breast cancer between January 1, 1997 to December 31, 2001 and followed up to December 31, 2007. Descriptive statistics were employed to analyze the epidemiological and clinical data. Estimates of overall, disease-free, and cancer-specific survival at 5 years were estimated by the Kaplan–Meier method and stage-specific relative survival rates were calculated.

Results

A total of 7,630 breast cancer patients’ medical records and dataset were available during this period, and 7,449 subjects were eligible for the final analysis. Median follow-up was 84 months. A total of 47.4% were diagnosed with breast cancer at age 49 years and younger; 22.2%, 46.9%, 10.8%, and 4.1% presented at stages I, II, III, and IV, respectively. A total of 53.5% had ER-positive cancer, and 20.3% had HER2-positive cancers; 13.4% had triple-negative cancers. The relative, cancer-specific, and disease-free survival rates at 5 years were 84%, 85.2%, and 81.2%, respectively.

Discussion

We performed the first comprehensive population-based breast cancer epidemiology study in Southern China using the Hong Kong Cancer Registry database. This provides a baseline study cohort for comparative studies with other Asian countries and Chinese who have migrated to the West.

Dietary intake of vitamin B(6) and risk of breast cancer in Taiwanese women

BACKGROUND

B vitamins, including vitamin B(6), are coenzymes that are important for DNA integrity and stability. Deficiencies in B vitamins may promote tumor carcinogenesis.

METHODS

We examined the association of dietary vitamin B(6) intake with overall breast cancer risk and breast cancers stratified by hormone receptor status. This case-control study included 391 breast cancer cases and 782 control subjects enrolled at the Tri-Service General Hospital in Taipei, Taiwan. Energy-adjusted intake of vitamin B(6) was derived from a food frequency questionnaire. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression.

RESULTS

As compared with women in the lowest tertile, the multivariate-adjusted ORs for breast cancer among women in the second and highest tertiles of vitamin B(6) intake were 0.78 (95% CI, 0.64-2.52) and 0.64 (0.26-0.92), respectively. In addition, higher vitamin B(6) intake was associated with a significantly lower risk of developing ER-negative breast tumors.

CONCLUSIONS

Our findings suggest that higher intake of vitamin B(6) is associated with a reduction in breast cancer risk, particularly ER-negative tumors.

Joint effect of peroxisome proliferator-activated receptor γ genetic polymorphisms and estrogen-related risk factors on breast cancer risk: results from a case-control study in Taiwan

Peroxisome proliferator-activated receptor γ (PPARγ) has been linked with possible antineoplastic effects in colorectal carcinogenesis. However, data for the possible link between PPARγ and breast cancer risk are sparse. We assessed the association of three polymorphisms in PPARγ (rs10865710 [C-681T], rs1805192 [Pro12Ala], and rs3856806 [C1431T]) with the risk of breast cancer in an ethnic Chinese female population in Taiwan. In addition, interactions with estrogen exposures were also explored. Genotypes for the PPARγ polymorphisms were determined on 291 incident breast cancer cases and 589 matched controls by fluorogenic 5'-nuclease assay. The at-risk haplotypes were defined according to the three polymorphisms in the following order: C-681T, Pro12Ala, and C1431T, which include CCT, GGT, and GGC. In addition, a critical period of estrogen exposure was estimated by the interval between age at menarche and age at first full-term pregnancy. Overall, there was no evidence of a significant impact of individual polymorphisms of PPARγ on breast cancer risk. However, the haplotype analysis revealed that women harboring at-risk haplotypes showed a significant 67% increase in breast cancer risk [adjusted odds ratio (OR) 1.67; 95% confidence interval (CI) 1.11-2.52]. Furthermore, there was a significant joint effect of estrogen exposure-related factors and at-risk haplotypes of PPARγ on breast cancer risk (adjusted OR 4.04; 95% CI 1.89-8.65), particularly in premenopausal women. The present study implicates a role for PPARγ in breast cancer risk. Mechanistic studies to fully elucidate the mechanisms underlying PPARγ's effects should be pursued in future investigations.