The Insulin-like Growth Factor Axis, Adipokines, Physical Activity, and Obesity in Relation to Breast Cancer Incidence and Recurrence

Investigating the trends of incidence rates of breast cancer in Southern Iran: a population based survey

BACKGROUND

The overall incidence of breast cancer is different all over the world and even within a nation. The present study aims to investigate the stratum-specific incidence trends of breast cancer in southern Iran.

METHODS

In this retrospective cohort study, the data of Fars Population-Based Cancer Registry was used during 2001-2018. New cancer cases with ICD-O-3 codes C50.0 to C50.9 were categorized based on age group, morphology, and topography. Age-specific incidence rates of breast cancer were calculated during 2001-2018. Annual overall and truncated age-standardized incidence rates and their 95% Confidence Intervals (CIs) were also calculated. Afterward, the Annual Percentage Changes (APCs) of the age-specific and age-standardized incidence rates of breast cancer during 2001-2018 were calculated using Joinpoint regression software.

RESULTS

An increasing trend was observed in the incidence of breast cancer among women during 2001-2018 (APC of age-standardized incidence rates: 9.5 (95% CI: 7.5, 11.5)).However, the trend was increasing less during the recent years. The APC of age-standardized rates decreased from 15.03 (95% CI: 10.4, 19.8) in 2007 to 6.15(95% CI: 4.0, 8.4) in 2018. The most common morphology of breast cancer was invasive ductal carcinoma (77.3% in females and 75.1% in males) and its trend was similar to the general trend of different types of breast cancer. The most common site of breast cancer was the upper outer quadrant. Most breast cancer cases were female and males accounted for 2.45% of the cases. Among females, 40-55 was the most prevalent age group.

CONCLUSION

The incidence of breast cancer among women living in southern Iran showed an increasing trend from 2001 to 2018. However, the rate of increase exhibited a milder slope during the more recent years. Based on the higher prevalence of breast cancer in the 40-55 age group observed in the present study, it offers valuable insight into the potential reduction of the breast cancer screening age from 50 to 40 years for healthy Iranian women. However, before implementing such a policy change, it is crucial to conduct additional studies that specifically examine the cost-effectiveness, as well as the potential benefits and risks associated with this alteration.

Effects of exercise on inflammatory factors and IGF system in breast cancer survivors: a meta-analysis

BACKGROUND

At present, there are multiple hypotheses regarding the mechanisms underlying the effect of exercise on the postoperative inflammatory factors and the IGF system among breast cancer patients, especially. To determine the underlying mechanisms, prevent the recurrence of breast cancer and improve its prognosis, this paper will systematically evaluate the impact of exercise on inflammatory factors and the IGF system in breast cancer survivors.

METHODS

The PubMed, Embase, Web of Science, CNKI, Wanfang and VIP (Chinese scientific and technical journals) databases were systematically searched until April 2021. The search terms included 'exercise', 'inflammatory factor', 'IGF system' and 'breast cancer'. A total of 1066 relevant articles were retrieved. The articles were screened according to inclusion and exclusion criteria, such as study population, intervention method and type of experiment, and 11 articles were ultimately included. All statistical results were analysed using STATA 14.0 and Rstudio 4.1.1.

RESULTS

We found that exercise significantly reduced the level of IGF-1 (WMD, -19.947 ng/ml; 95% CI, -22.669 to -17.225; P = 0.000). Subgroup analysis showed that in the studies with an intervention period > 12 weeks, exercise significantly reduced IL-6 levels (WMD, -0.761 pg/ml; 95% CI, -1.369 to -0.153; p = 0.014), while in the studies with an intervention period ≤ 12 weeks, exercise significantly reduced CRP (WMD, -2.381 mg/L; 95% CI, -4.835 to 0.073, P = 0.001) and IL-10 levels (WMD, -7.141 pg/ml, 95% CI, -10.853 to -3.428; P = 0.000). In addition, aerobic exercise plus resistance training significantly reduced IL-6 levels (WMD, -1.474 pg/ml; 95% CI, -1.653 to -1.296; P = 0.000). The results of the sensitivity analysis showed that after excluding the studies with high heterogeneity, exercise significantly reduced the TNF-α levels in patients with breast cancer (WMD, -1.399 pg/ml; 95% CI, -1.718 to -1.080; P = 0.000).

CONCLUSION

Exercise reduces the postoperative levels of IGF-1, IL-6, CRP, IL-10 and TNF-α among patients with breast cancer, which may have a significant impact on inhibiting breast cancer recurrence and improving its prognosis. Future studies should examine the effects of different durations and types of exercise to develop individualized exercise prescriptions for breast cancer patients.

Frailty and aging in cancer survivors

There are over 15 million survivors of cancer in the United States whose rates of frailty, an aging phenotype, range from just under 10% to over 80%. Frailty impacts not only disease survival but also long-term function and quality of life in children, adolescents, and in all adults diagnosed and/or treated for cancer. This review explains frailty as a construct and model of physiologic well-being. It also describes how frailty at diagnosis impacts cancer outcomes in adult populations and enumerates the prevalence of frailty in different populations of cancer survivors. Biological mechanisms responsible for aging and potentially for frailty among individuals with or who have been treated for cancer are discussed. Finally, promising pharmaceutical and lifestyle interventions designed to impact aging rather than a specific disease, tested in other populations, but likely applicable in cancer patients and survivors, are discussed.

Use of consumer wearable devices to promote physical activity among breast, prostate, and colorectal cancer survivors: a review of health intervention studies

PURPOSE

A growing amount of research has successfully incorporated Fitbit devices and other wearable activity trackers into technology-oriented lifestyle interventions to increase physical activity among cancer survivors.

METHODS

The present review of this literature is based upon bibliographic searches in PubMed and CINAHL and relevant search terms. Articles published in English from January 1, 2009, through October 16, 2019, were considered.

RESULTS

A total of 1726 article citations were identified in PubMed and non-duplicates in CINAHL. After screening the abstracts or full texts of these articles and reviewing the references of previous review articles, we found 13 studies that met the eligibility criteria. Of these, 8 were randomized controlled trials, one was a pre-post-test trial, and 4 were qualitative studies (focus groups, in-depth interviews). The studies focused on breast cancer (n = 8), prostate cancer (n = 2), and colorectal cancer (n = 1), and the remainder focused on more than one cancer site.

CONCLUSIONS

Additional research is needed to examine the efficacy of consumer wearable devices in promoting physical activity and weight management among cancer survivors.

IMPLICATIONS FOR CANCER SURVIVORS

Cancer survivors show an increase in physical activity when using consumer wearable activity trackers. Increased physical activity plays an important role in alleviating many adverse effects of breast cancer therapy as well as improving morbidity and mortality. Additional research such as clinical trials focused on the development of successful interventions utilizing these devices is warranted.

A review of home-based physical activity interventions for breast cancer survivors

As breast cancer relative survival continues to increase, many breast cancer patients face many issues, including recurrence of cancer and cancer-related side effects that impact several aspects of their quality of life. With breast cancer patients living longer, there is more of a concern for negative breast cancer outcomes. Although physical activity is an affordable and relatively convenient way to improve breast cancer outcomes, only about one-third of breast cancer survivors engage in the recommended level of physical activity. This article reviews articles published to date to examine whether home-based physical activity interventions are effective in improving physical activity and other outcomes among breast cancer survivors who have completed primary therapy for the disease. The present review is based upon bibliographic searches in PubMed and CINAHL and relevant search terms. Articles published in English from 1980 through February 28, 2019 were identified. A total of 360 article citations were identified in PubMed and non-duplicates in CINAHL. After screening the abstracts or full texts of these articles and reviewing the references of previous review articles, 20 studies that met the eligibility criteria. Three of the studies were pre-/post-test trials and 17 were randomized controlled trials. home-based exercise programs are effective in improving physical activity among breast cancer survivors who have completed primary therapy for the disease. Home-based exercise programs such as walking programs offer a convenient and affordable option for women who wish to increase their physical activity and maintain a healthy lifestyle.

Oncologists' Perceptions of a Digital Tool to Improve Cancer Survivors' Cardiovascular Health

Background

Cardiovascular (CV) disease continues to be a leading cause of morbidity and mortality with higher rates among cancer survivors than in the general population.

Objective

This study was aimed to understand oncology providers' attitudes toward a digital CV health tool, delivered via a tablet, to promote CV health in cancer survivors.

Methods

Using qualitative methods, 14 oncologists, from community and academic practice sites, were interviewed while they used the tool. Interviews were videotaped then analyzed using NVivo 11 software. Themes were inductively developed from the interviews.

Results

Three major themes emerged from the interviews as follows: (1) system functionality, (2) facilitators and barriers to integration, and (3) appropriate end-users. Oncologists recognized the critical role of CV health promotion among cancer survivors and identified features about the tool that would be helpful for CV health promotion. Workflow (subtheme) was a barrier to tool use. This feedback enabled tool redesign for further testing in the context of survivorship care.

Conclusion

Our findings emphasized the importance of identifying appropriate End-users which may include other survivorship care providers, patients, and primary care providers.

Implications

Our research addresses the knowledge gap in the use of digital tools in cancer survivorship care, specifically digital tools to promote CV health. Future research is needed to evaluate digital tools in cancer survivorship care. Research investigating patients as users of digital tools may provide additional insight.

Physical Activity, Weight Control, and Biomarkers of Prognosis and Survival among Breast Cancer Survivors

Physical inactivity and obesity may increase risk of poor prognosis in breast cancer through effects on insulin or insulin-like growth factors or their binding proteins, insulin resistance, glucose metabolism, sex hormones, leptin and other adipokines, immunologic or inflammatory factors, oxidative stress, and Deoxyribonucleic acid (DNA) damage or repair capacity. The present review is based upon bibliographic searches in PubMed and relevant search terms. Articles published in English from January 1, 1980 through October 1, 2018 were identified using the following MeSH search terms and Boolean algebra commands: breast cancer survivors AND (insulin-like growth factor OR insulin resistance OR glucose metabolism OR sex hormones OR leptin OR adipokines OR immunologic OR inflammatory factors OR oxidative stress OR DNA repair capacity). After screening the abstracts or full texts of these articles and reviewing the references of previous review articles, a total of 66 studies met the eligibility criteria. Based upon published studies, it is difficult to determine the type or dose of exercise that affects inflammatory markers among breast cancer survivors. The optimal type of exercise, dose, and timing of physical activity needed to improve the inflammatory profile following a breast cancer diagnosis is unknown. Studies have used a range of physical activity types including aerobic, resistance training, yoga, and Tai Chi. A further issue is that existing studies of physical activity and biomarkers have included a range of disease stages. There is a need for a better understanding of the biological pathways through which physical activity and weight management increase survival in order to design targeted weight loss and exercise interventions for breast cancer survivors.

Neurocalcin-delta: a potential memory-related factor in hippocampus of obese rats induced by high-fat diet

Introduction

Aberrant protein expression within the hippocampus has recently been implicated in the pathogenesis of obesity-induced memory impairment.

Objectives

The objective of the current study was to search for specific memory-related factors in the hippocampus in obese rats.

Methods

Sprague-Dawley (SD) rats were fed either a high-fat (HF) diet or normal-fat (NF) diet for 10 weeks to obtain the control (CON), diet-induced obese rats (DIO) and diet-resistant (DR) rats. D-galactose was injected subcutaneously for 10 weeks to establish model (MOD) rats with learning and memory impairment. After the hippocampus of the rats sampling, the proteome analysis was conducted using two-dimensional get electrophoresis (2-DE) combined with peptide mass fingerprinting (PMF).

Results

We found 15 differential proteins that expressed in the hippocampus in rats induced by HF diet from the 2-DE map. In addition, Neurocalcin-delta (NCALD) was nearly down-regulated in the DR rats compared with CON rats and MOD rats, which was further confirmed by Western blot, real-time PCR and ELISA results.

Conclusion

Our data demonstrates that the differential memory-related proteins were a reflection of the HF diet, but not potential factors in obesity proneness or obesity resistance. Furthermore, NCALD is proved to be a potential hippocampus-memory related factor related to obesity.

The Effects of Resistance Exercise on Biomarkers of Breast Cancer Prognosis: A Pooled Analysis of Three Randomized Trials

Background: Using a secondary data analysis from randomized controlled trials comparing one year of resistance exercise (n = 109) to a placebo control condition (n = 106) in postmenopausal, posttreatment breast cancer survivors, we investigated the influence of resistance training and changes in body composition on markers associated with cancer progression.Methods: Measures included serum levels of insulin, IGF-1, IGFBP1-3, leptin, serum amyloid A (SAA), adiponectin, C-reactive protein (CRP), IL1β, TNFα, IL6, and IL8, and body composition (total, lean and fat mass in kg) by DXA at baseline, 6, and 12 months. Linear mixed effects models were used to examine the association between group, biomarkers, and body composition and whether or not changes in muscle strength or body composition influenced the effect of exercise on biomarkers.Results: CRP decreased over time among women participating in resistance training compared with increases in controls (P = 0.045). In stratified analyses and compared with increases in controls, women who gained strength reduced CRP (P = 0.003) and maintained levels of IL1β and IL6. Among exercisers who lost weight (≥2 kg), CRP (P = 0.045), leptin (P < 0.01), and SAA (P = 0.029) decreased, whereas IGF-BP1 (P = 0.036) increased compared with controls.Conclusions: Resistance training may lower inflammation and improve insulin pathway profiles, but the magnitude and degree of benefit from exercise may depend upon whether or not women gained strength, a possible marker of compliance with training, and/or lost weight during exercise.Impact: Future resistance training trials should consider these potential influencing factors as they may determine how well exercise can slow cancer progression and prevent disease recurrence. Cancer Epidemiol Biomarkers Prev; 27(2); 146-53. ©2017 AACR.

A New Gene Expression Signature for Triple Negative Breast Cancer Using Frozen Fresh Tissue before Neoadjuvant Chemotherapy

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer tumors. Comparisons between TNBC and non-triple negative breast cancer (nTNBC) may help to differentiate key components involved in TNBC neoplasms. The purpose of the study was to analyze the expression profile of TNBC versus nTNBC tumors in a homogeneous population from northeastern Mexico. A prospective study of 50 patients was conducted (25 TNBC and 25 nTNBC). Clinic parameters were equally distributed for TNBC and nTNBC: age at diagnosis (51 vs 47 years, p=0.1), glucose levels (107 mg/dl vs 104 mg/dl, p=0.64), and body mass index (28 vs 29, p=0.14), respectively. Core biopsies were collected for histopathological diagnosis and gene expression analyses. Total RNA was isolated and expression profiling was performed. 40 genes showed differential expression pattern in TNBC tumors. Among these, 9 over-expressed genes (PRKX/PRKY, UGT8, HMGA1, LPIN1, HAPLN3, and ANKRD11), and one under-expressed (ANX9) gene are involved in general metabolism. Based on this biochemical peculiarity, and the over-expression of BCL11A and FOXC1 (involved in tumor growth and metastasis, respectively) we validated by qPCR the expression profile of 7 genes out of the signature. In this report, a new gene signature for TNBC is proposed. To our knowledge, this is the first TNBC signature which describes genes involved in general metabolism. The findings may be pertinent for Mexican patients and require to be evaluated in further ethnic groups and populations.

Postdiagnosis Weight Change and Survival Following a Diagnosis of Early-Stage Breast Cancer

BACKGROUND

Achieving a healthy weight is recommended for all breast cancer survivors. Previous research on postdiagnosis weight change and mortality had conflicting results.

METHODS

We examined whether change in body weight in the 18 months following diagnosis is associated with overall and breast cancer-specific mortality in a cohort of n = 12,590 stage I-III breast cancer patients at Kaiser Permanente using multivariable-adjusted Cox regression models. Follow-up was from the date of the postdiagnosis weight at 18 months until death or June 2015 [median follow-up (range): 3 (0-9) years]. We divided follow-up into earlier (18-54 months) and later (>54 months) postdiagnosis periods.

RESULTS

Mean (SD) age-at-diagnosis was 59 (11) years. A total of 980 women died, 503 from breast cancer. Most women maintained weight within 5% of diagnosis body weight; weight loss and gain were equally common at 19% each. Compared with weight maintenance, large losses (≥10%) were associated with worse survival, with HRs and 95% confidence intervals (CI) for all-cause death of 2.63 (2.12-3.26) earlier and 1.60 (1.14-2.25) later in follow-up. Modest losses (>5%-<10%) were associated with worse survival earlier [1.39 (1.11-1.74)] but not later in follow-up [0.77 (0.54-1.11)]. Weight gain was not related to survival. Results were similar for breast cancer-specific death.

CONCLUSION

Large postdiagnosis weight loss is associated with worse survival in both earlier and later postdiagnosis periods, independent of treatment and prognostic factors.

IMPACT

Weight loss and gain are equally common after breast cancer, and weight loss is a consistent marker of mortality risk. Cancer Epidemiol Biomarkers Prev; 26(1); 44-50. ©2016 AACR SEE ALL THE ARTICLES IN THIS CEBP FOCUS SECTION, "THE OBESITY PARADOX IN CANCER EVIDENCE AND NEW DIRECTIONS".

Development of the Physical activity and Your Nutrition for Cancer (PYNC) smartphone app for preventing breast cancer in women

BACKGROUND

In the U.S., breast cancer accounts for more cancer deaths in women than any site other than lung cancer. Based upon attributable risks, about 30-35% of breast cancers could potentially be prevented by addressing obesity, physical inactivity, increased alcohol consumption, and carcinogenic exposures such as hormone replacement therapy (HRT). We need methods of reducing women's risks of this disease that are attractive and easy to use, widely accessible to diverse women, and able to be easily amended to account for new research.

METHODS

The overall objective of this 12-month project is to develop and test a smartphone app to provide women with information about how they can reduce their risk of breast cancer through healthy behaviors such as physical activity, weight management, restricting caloric intake, consuming a healthy diet and proper nutrition, engaging in regular physical activity, and avoiding carcinogenic exposures such as HRT and alcohol. The specific aims are: (I) to develop a smartphone app for breast cancer prevention using a behavioral framework; (II) to ensure interconnectivity with commercially available products (Fitbit device for monitoring physical activity and the LoseIt! smartphone app for monitoring and tracking diet and nutrition); and (III) to ensure that the mHealth intervention is suitable for women with varying levels of health literacy and eHealth literacy.

RESULTS

The app, referred to as Physical activity and Your Nutrition for Cancer (PYNC), is being coded on an iOS platform. Users will be able to access the breast cancer prevention app using their smartphone or tablet. The app's design will ensure interconnectivity with commercially available products for monitoring and tracking physical activity, caloric intake, diet and nutrition. Using the app, it will be feasible for users to connect and sync their Fitbit and LoseIt! accounts so that information collected about physical activity, caloric intake, diet, and nutrition can be conveniently assessed from one portal. The Fitbit device and app provides reminders and allows users to set physical activity goals. Users will be able to access health education information about breast cancer risk-reduction with attractive graphics and visual displays.

CONCLUSIONS

Future directions will include testing the efficacy of the mHealth intervention in increasing physical activity, improving diet and nutrition, and weight management through a randomized controlled trial, and widespread dissemination and implementation research.

Elevated Serum Levels of Retinol-Binding Protein 4 Are Associated with Breast Cancer Risk: A Case-Control Study

Background

Retinol binding protein 4 (RBP4) is a recently identified adipokine that is elevated in patients with obesity or type 2 diabetes. A growing body of research has shown that RBP4 is associated with several types of cancer. However, no studies have investigated the relationship between serum RBP4 levels and breast cancer risk. We performed a case-control study to evaluate the association between serum RBP4 levels and the risk of breast cancer.

Methods

From August 2012 to December 2013, four-hundred subjects including 200 patients diagnosed with primary breast cancer and 200 matched healthy women were consecutively enrolled from Affiliated Hospital of Qingdao University Medical College. Blood samples were collected from healthy controls and breast cancer patients before commencement of treatment. Enzyme-linked immunosorbent assay was used to evaluate the serum RBP4 levels in separated serum samples. Meanwhile, the characteristics of breast cancer cases and controls were collected from medical records and pathological data.

Results

The serum levels of RBP4 were significantly higher in patients with breast cancer than that in the healthy control group (33.77±9.92 vs. 28.77±6.47μg/ml, P < 0.05). Compared to the subjects in the lowest quartile of serum RBP4 level, the adjusted ORs (95% CIs) is 2.16(1.01–4.61) and 2.07 (1.07–4.00) for women in the second and highest RBP4 tertile, respectively. For breast cancer patients, patients with PR or ER negative displayed significantly higher serum RBP4 levels than those with PR or ER positive.

Conclusion

Our results for the first time suggested serum RBP4 levels could be associated with the risk of breast cancer. However, further prospective studies are essential to confirm these observed results.

Role of n-3 Polyunsaturated Fatty Acids and Exercise in Breast Cancer Prevention: Identifying Common Targets

Diet and exercise are recognized as important lifestyle factors that significantly influence breast cancer risk. In particular, dietary n-3 polyunsaturated fatty acids (PUFAs) have been shown to play an important role in breast cancer prevention. Growing evidence also demonstrates a role for exercise in cancer and chronic disease prevention. However, the potential synergistic effect of n-3 PUFA intake and exercise is yet to be determined. This review explores targets for breast cancer prevention that are common between n-3 PUFA intake and exercise and that may be important study outcomes for future research investigating the combined effect of n-3 PUFA intake and exercise. These lines of evidence highlight potential new avenues for research and strategies for breast cancer prevention.

Towards research-tested smartphone applications for preventing breast cancer

Efforts to prevent breast cancer and other chronic illnesses have focused on promoting physical activity, healthy diet and nutrition, and avoidance of excessive alcohol consumption. Smartphone applications (apps) offer a low-cost, effective strategy for breast cancer prevention in women through behavioral change. However, there are currently no research-tested smartphone apps for breast cancer prevention that are suitable for women with varying levels of health literacy and eHealth literacy. In this perspective, we consider modifiable risk factors for breast cancer in women in relation to the development of smartphone apps to promote healthy behaviors associated with breast cancer-risk reduction. First, we provide a summary of breast cancer risk factors that are modifiable through behavioral change including their corresponding relative risk. Second, we discuss scientific issues related to the development of smartphone apps for the primary prevention of breast cancer and offer suggestions for further research. Smartphone apps for preventing breast cancer should be tailored for women at different life stages (e.g., young women, women who are post-menopausal, and older women). Topics such as breastfeeding and oral contraceptives are appropriate for younger women. Weight management, physical activity, avoiding cigarette smoking, and dispelling breast cancer myths are appropriate for women of all ages. As women age, topics such as hormone replacement therapy or comorbid health conditions become more important to address. Apps for breast cancer prevention should be grounded in a behavioral theory or framework and should be suitable for people with varying levels of health literacy. Future developments in smartphone apps for breast cancer prevention should include apps that are tailored for specific cultural, racial, and ethnic groups.

The Association between Treatment for Metabolic Disorders and Breast Cancer Characteristics

Purpose. To evaluate the associations between metformin, insulin, statins, and levothyroxine and breast cancer characteristics and outcome. Methods. Retrospective chart review of patients treated in our institute for early estrogen receptor (ER) positive, human epidermal growth factor receptor 2 negative breast cancer, whose tumors were sent to Oncotype DX (ODX) analysis. Patients were grouped according to medications usage during the time of breast cancer diagnosis. Each group was compared to the rest of the study population. Results. The study cohort included 671 patients. Sixty (9.1%) patients were treated with metformin, 9 (1.4%) with insulin, 208 (31.7%) with statins, and 62 (9.4%) with levothyroxine. Patients treated with metformin had more intense ER stain (p = 0.032) and a lower ODX recurrence score (RS) (p = 0.035). Diagnosis of diabetes mellitus was also associated with lower ODX RS (p = 0.014). Insulin usage was associated with a higher rate of angiolymphatic invasion (p = 0.041), but lower Ki67% (p = 0.017). Levothyroxine usage was associated with different histological subtype distribution (p = 0.02). Extended levothyroxine usage was associated with lower ODX RS (p = 0.005). Statin usage had no impact on tumor characteristics. Outcome was comparable in the studied subgroups. Conclusions. Common medications for metabolic disorders might be associated with breast cancer characteristics.

Serum irisin levels are lower in patients with breast cancer: association with disease diagnosis and tumor characteristics

Background

Irisin is a recently discovered myokine, involved in the browning of white adipose tissue. To date, its function has been mainly associated with energy homeostasis and metabolism, and it has been proposed as a promising therapeutic target for obesity and metabolic diseases. This is the first study investigating the role of irisin in human breast cancer.

Methods

Participants included one hundred and one (101) female patients with invasive ductal breast cancer and fifty one (51) healthy women. Serum levels of irisin, leptin, adiponectin and resistin were quantified in duplicates by ELISA. Serum levels of CEA, CA 15–3 and Her-2/neu were measured on an immunology analyzer. The association between irisin and breast cancer was examined by logistic regression analysis. The feasibility of serum irisin in discriminating breast cancer patients was assessed by ROC curve analysis. Potential correlations with demographic, anthropometric and clinical parameters, with markers of adiposity and with breast tumor characteristics were also investigated.

Results

Serum levels of irisin were significantly lower in breast cancer patients compared to controls (2.47 ± 0.57 and 3.24 ± 0.66 μg/ml, respectively, p < 0.001). A significant independent association between irisin and breast cancer was observed by univariate and multivariate analysis (p < 0.001). It was estimated that a 1 unit increase in irisin levels leads to a reduction in the probability of breast cancer by almost 90 %. Irisin could effectively discriminate breast cancer patients at a cut-off point of 3.21 μg/ml, with 62.7 % sensitivity and 91.1 % specificity. A positive association with tumor stage and marginal associations with tumor size and lymph node metastasis were observed (p < 0.05, p < 0.01, p < 0.01, respectively).

Conclusions

Our novel findings implicate irisin in breast cancer and suggest its potential application as a new diagnostic indicator of the presence of disease.

Association between exonic polymorphism (rs629849, Gly1619Arg) of IGF2R gene and obesity in Korean population

The aim of this study is to investigate the relationship between single nucleotide polymorphisms (SNPs) and susceptibility to obesity. A previous study suggested that insulin-like growth factors (IGFs) may affect obesity and that IGFs regulate cellular signals by receptors that include the insulin-like growth factor 1 receptor (IGF1R) and the insulin-like growth factor 2 receptor (IGF2R). In this research, the rs3743262 and rs2229765 SNPs of IGF1R gene and rs629849 and rs1805075 SNPs of IG-F2R gene were genotyped in 120 overweight and obese patients with a BMI≥23 kg/m2 (Body Mass Index) and 123 healthy controls with a BMI of 18.5–23.0 kg/m2. Genotyping of each SNP was performed by direct sequencing. Among tested SNPs in IGF1R and IGF2R genes, rs629849 SNP of IGF2R gene showed significant association with obesity (OR=1.86, 95% CI=1.02–3.40, P=0.044 in codominant1 model; OR=1.99, 95% CI=1.10–3.57, P=0.020 in dominant model; OR=1.93, 95% CI=1.13–3.31, P=0.013 in log-additive model). And allele distribution between the control group and overweight/obese group also showed significant difference (OR=1.93, 95% CI=1.14–3.28, P=0.015). In conclusion, these results indicate that rs629849 SNP of IGF2R might be contributed to development of obesity in the Korean population.

The Impact of the Natural, Social, Built, and Policy Environments on Breast Cancer

BACKGROUND

The global burden of breast cancer in women is substantial and increasing. Efforts to address breast cancer have focused on primary prevention, reduction of modifiable risk factors, early detection, timely referral for appropriate treatment, and survivorship. Environmental and lifestyle factors that increase breast cancer risk include ionizing radiation, exogenous hormones, certain female reproductive factors, alcohol and other dietary factors, obesity, and physical inactivity. A variety of chemical exposures are purported to be associated with breast cancer.

METHODS

In this article, we summarize the influence of the natural, social, built, and policy environments on breast cancer incidence and cancer recurrence in women based upon bibliographic searches and relevant search terms.

RESULTS

Despite a lack of conclusive evidence from epidemiologic studies, exposures to chemicals with estrogenic or other properties relevant to sex steroid activity could influence breast cancer risk if the exposures occur at critical life stages or in combination with exposure to other similar chemicals. Results from several studies support an association between shift work and disruption of the circadian rhythm with breast cancer risk. The social environment likely influences breast cancer risk through several mechanisms including social norms pertaining to breast feeding, age at first live birth, parity, use of oral contraceptives and replacement estrogens, diet, and consumption of alcohol. Social norms also influence body weight, obesity, and physical activity, which have an effect on risk of breast cancer incidence and recurrence. Obesity, which is influenced by the social, built, and policy environments, is a risk factor for the development of postmenopausal breast cancer and certain other cancer types.

CONCLUSIONS

The natural, social, built, and policy environments affect breast cancer incidence and survival. Effective health care policies can encourage the provision of high-quality screening and treatment for breast cancer and public education about the value of proper diet, weight control, screening and treatment. Additional research and policy development is needed to determine the value of limiting exposures to potentially carcinogenic chemicals on breast cancer prevention.

Estrogen Receptor-β and the Insulin-Like Growth Factor Axis as Potential Therapeutic Targets for Triple-Negative Breast Cancer

Triple-negative breast cancers (TNBCs) lack estrogen receptor-α (ERα), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2) amplification and account for almost half of all breast cancer deaths. This breast cancer subtype largely affects women who are premenopausal, African-American, or have BRCA1/2 mutations. Women with TNBC are plagued with higher rates of distant metastasis that significantly diminish their overall survival and quality of life. Due to their poor response to chemotherapy, patients with TNBC would significantly benefit from development of new targeted therapeutics. Research suggests that the insulin-like growth factor (IGF) family and estrogen receptor beta-1 (ERβ1), due to their roles in metabolism and cellular regulation, might be attractive targets to pursue for TNBC management. Here, we review the current state of the science addressing the roles of ERβ1 and the IGF family in TNBC. Further, the potential benefit of metformin treatment in patients with TNBC as well as areas of therapeutic potential in the IGF-ERβ1 pathway are highlighted.