Insulin-like growth factor binding proteins 1 and 3 and breast cancer outcomes

Serum IGFBP-1 as a promising diagnostic and prognostic biomarker for colorectal cancer

Our previous study showed that levels of circulating insulin-like growth factor binding protein-1 (IGFBP-1) has potential diagnostic value for early-stage upper gastrointestinal cancers. This study aimed to assess whether serum IGFBP-1 is a potential diagnostic and prognostic biomarker for CRC patients. IGFBP-1 mRNA expression profile data of peripheral blood in colorectal cancer (CRC) patients were downloaded and analyzed from Gene Expression Omnibus database. We detected serum IGFBP-1 in 138 CRC patients and 190 normal controls using enzyme-linked immunosorbent assay. Blood IGFBP-1 mRNA levels were higher in CRC patients than those in normal controls (P = 0.027). In addition, serum IGFBP-1 protein levels in the CRC group were significantly higher than those in normal control group (P < 0.0001). Serum IGFBP-1 demonstrated better diagnostic accuracy for all CRC and early-stage CRC, respectively, when compared with carcinoembryonic antigen (CEA), carbohydrate antigen19-9 (CA 19-9) or the combination of CEA and CA19-9. Furthermore, Cox multivariate analysis revealed that serum IGFBP-1 was an independent prognostic factor for OS (HR = 2.043, P = 0.045). Our study demonstrated that serum IGFBP-1 might be a potential biomarker for the diagnosis and prognosis of CRC. In addition, the nomogram might be helpful to predict the prognosis of CRC.

Physical Activity and Breast Cancer Survival-Epidemiologic Evidence and Potential Biologic Mechanisms

PURPOSE OF REVIEW

To review the biologic mechanisms that may be operative between physical activity and survival after breast cancer.

RECENT FINDINGS

Physical activity decreases risk of mortality from breast cancer by up to 40%. Several biologic mechanisms have been hypothesized to explain this association. Previous cohort studies and randomized trials have examined the primary mechanisms that appear to be operative, which involve a decrease in sex hormone levels, insulin resistance, and inflammation. The evidence is still inconsistent and several limitations in the existing literature exist. Understanding the biologic mechanisms involved in the association of physical activity and breast cancer survival will provide more precision to physical activity guidelines for cancer survival. To achieve this objective, future research should include direct measurements of physical activity, sedentary behaviour, and health-related fitness to provide a more comprehensive assessment of these factors and their association with biomarkers and survival after breast cancer.

Pre-treatment high body mass index is associated with poor survival in Asian premenopausal women with localized breast cancer

Background: Obesity is associated with poor prognosis in breast cancer patients. This study aimed to evaluate the effect of obesity measured by body mass index (BMI) on survival of Taiwanese breast cancer patients in a single institution.

Methods: We observed 5000 patients who were diagnosed with stage I-III breast cancer between 1990 and 2005. Information on BMI at diagnosis, and clinical follow-up for disease recurrence and death, up to 20 years post-diagnosis were available. BMI (in kg/m²) categories included normal weight (BMI<24), overweight (24≤BMI<27), and obesity (BMI≥27), according to recommendations from the Bureau of Health Promotion of Taiwan. The role of BMI and other known prognostic factors for patient survival were evaluated in this patient cohort.

Results: Obesity was associated with advanced stage, higher nuclear grade, and higher percentages of estrogen receptor (ER) positive. The median age of patients with a higher BMI was greater than the median age of patients with a lower BMI. Obesity was an independent prognostic factor of overall survival (OS) (P<0.001), but not disease-free survival (DFS) (P=0.067). We subsequently analyzed the impact of age-stratified BMI (age<50 and age≥50 years) to ameliorate the impact of age bias. Following subset analyses, obesity correlated with shorter DFS (P=0.004) and OS (P=0.009) only in women<50 years of age. Multivariate analysis revealed that BMI was an independent prognostic factor for both DFS and OS in this group of patients. Subset analysis revealed that in women <50 years old, the impact of BMI on survival was associated with higher stage, ER negativity.

Conclusion: BMI is an independent prognostic factor of OS and DFS in breast cancer patients aged<50 years. Although the cause-effect relationship between obesity and survival is unclear, we recommend that weight control measures in young breast cancer survivors should be considered.

IGFBP-1 in cancer: expression, molecular mechanisms, and potential clinical implications

Insulin-like growth factor binding protein-1 (IGFBP-1) belongs to the insulin-like growth factor (IGF) system, which plays an indispensable role in normal growth and development, and in the pathophysiology of various tumors. IGFBP-1 has been shown to be associated with the risk of various tumors, and has a vital function in regulating tumor behaviors such as proliferation, migration, invasion and adhesion through different molecular mechanisms. The biological actions of IGFBP-1 in cancer are found to be related to its phosphorylation state, and the IGF-dependent and -independent mechanisms. In this review, we provided an overview of IGFBP-1 in normal physiology, and its aberrantly expression and the underlying molecular mechanisms in a range of common tumors, as well as discussed the potential clinical implications of IGFBP-1 as diagnostic or prognostic biomarkers in cancer.

The Prognostic Values of the Insulin-Like Growth Factor Binding Protein Family in Ovarian Cancer

Purpose

To assess the expression of insulin-like growth factor binding protein (IGFBP) family and its prognostic impact in ovarian cancer (OC) patients.

Materials and Methods

The mRNA expression and protein expression of individual IGFBPs in healthy ovarian samples and OC tissues were explored through Oncomine, Gene Expression Profiling Interactive Analysis, and Human Protein Atlas database. Additionally, the prognostic values of the six IGFBP members in patients with OC were evaluated by Kaplan-Meier plotter.

Results

IGFBP2 and IGFBP4 mRNA expression were remarkably upregulated in patients with OC. To be specific, the mRNA expression of IGFBP2 was upregulated in patients with serous ovarian cancer (SOC), while IGFBP1/3/4/5/6 mRNA levels were downregulated. In addition, the IGFBP4 protein expression was upregulated in SOC, and the IGFBP6 protein expression was upregulated in both of SOC and endometrioid ovarian cancer (EOC) tissues. High IGFBP1 mRNA levels showed favorable overall survival (OS) and progression-free survival (PFS) in all OC. Meanwhile, increased IGFBP5/6 mRNA levels revealed worsen OS and PFS in all OC patients. IGFBP4/6 mRNA levels predicted unfavorable OS and PFS only in SOC patients. Moreover, the aberrant mRNA expression of IGFBP1/2/4/5/6 was correlated with significantly prognosis in patients receiving different chemotherapeutic regimens.

Conclusion

This study indicates that the IGFBP family reveals distinct prognosis in patients with OC. IGFBP1/2/4/5/6 are useful prognostic predictors for chemotherapeutic effect in OC patients, and IGFBP2/4 are potential tumor markers for the diagnosis of OC.

Circulating growth factor concentrations and breast cancer risk: a nested case-control study of IGF-1, IGFBP-3, and breast cancer in a family-based cohort

Background

Insulin-like growth factor 1 (IGF-1) and binding protein 3 (IGFBP-3) are associated with breast cancer in women at average risk of cancer. Less is known whether these biomarkers also predict risk in women with breast cancer family history.

Methods

We conducted a nested case-control study within the New York site of the Breast Cancer Family Registry (BCFR, n = 80 cases, 156 controls), a cohort enriched for breast cancer family history. Using conditional logistic regression, we estimated the association between IGF-1 and IGFBP-3 levels and breast cancer risk and examined whether this risk differed by predicted absolute breast cancer risk based on pedigree models.

Results

The overall association between IGF-1 or IGFBP-3 elevation (≥ median in controls) and breast cancer risk was elevated, but not statistically significant (IGF-1 OR = 1.37, 95% CI = 0.66–2.85; IGFBP-3 OR = 1.62, 95% CI = 0.81–3.24). Women with elevated predicted absolute 10-year risk ≥ 3.4% and elevated IGFBP-3 (≥ median) had more than a 3-fold increased risk compared to women with lower predicted absolute 10-year risk (< 3.4%) and low IGFBP-3 (OR = 3.47 95% CI = 1.04–11.6).

Conclusions

These data offer some support that the overall magnitude of the associations between IGF-1 and IGFBP3 seen in average risk cohorts may be similar in women enriched with a strong breast cancer family history.

Biomarker Modulation Study of Celecoxib for Chemoprevention in Women at Increased Risk for Breast Cancer: A Phase II Pilot Study

In preclinical studies, celecoxib has been associated with reduced risk of breast cancer. In this study, the aim was to assess the biomodulatory effect of celecoxib on blood and benign breast tissue biomarkers in women at increased risk for breast cancer. Women at increased risk for breast cancer [5-year Gail risk score of >1.67%, history of atypical hyperplasia, lobular carcinoma in situ, or previous estrogen receptor (ER)-negative breast cancer] were treated with celecoxib at 400 mg orally twice daily for 6 months. Participants underwent random periareolar fine needle aspiration and blood draw at baseline and at 6 months for analysis of biomarkers: serum levels of insulin-like growth factor 1 (IGF-1), IGF-binding protein 1 (IGFBP-1), and IGFBP-3; tissue expression of Ki-67 and ER; as well as cytology. Forty-nine patients were eligible for analysis. Median IGFBP-1 levels increased significantly from 6.05 ng/mL at baseline to 6.93 ng/mL at 6 months (P = 0.04), and median IGFBP-3 levels decreased significantly from 3,593 ng/mL to 3,420 ng/mL (P = 0.01). We also detected favorable changes in cytology of 52% of tested sites after 6 months of celecoxib therapy. No changes in tissue Ki-67 and ER expression levels were observed. No grade 3 or 4 toxicity was recorded. Celecoxib was well tolerated and induced favorable changes in serum biomarkers as well as cytology in this pilot phase II trial. A phase IIb placebo-controlled study with celecoxib could be considered for women at increased risk for breast cancer.

The prognostic values of insulin-like growth factor binding protein in breast cancer

Insulin-like growth factor binding proteins (IGFBPs) are a family of proteins binding to insulin-like growth factors, generally consisting 6 high-affinity IGFBPs, namely IGFBP1 through IGFBP6. IGFBP family members have been indicated to be involved in the development and progression of tumors and may be useful prognostic biomarkers in various malignancies. However, the prognostic role of individual IGFBPs, especially at the mRNA level in breast cancer patients remains elusive.We accessed the prognostic roles of IGFBPs family (IGFBP1-6) in breast cancer through the "Kaplan-Meier plotter" online database and OncoLnc database.Our results showed that the high expression of IGFBP1 mRNA was associated with favorable relapsed free survival (RFS) in all breast cancer patients. The high expression of IGFBP2 mRNA was associated with favorable overall survival (OS) and RFS in all breast cancer patients. The high expression of IGFBP3 mRNA was significantly correlated to worsen RFS in all breast cancer patients. The high expression of IGFBP4 mRNA was associated with favorable OS, RFS, distant metastasis-free survival, and post-progression survival in all breast cancer patients.Our results indicated that expression of IGFBPs mRNA may have prognostic values in breast cancer patients, and have a benefit for developing tools to predict the prognosis more accurately.

Effects of drospirenone and norethisterone acetate combined with estradiol on mammographic density and proliferation of breast epithelial cells-A prospective randomized trial

OBJECTIVE

There are no previous data on the influence of drospirenone (DRSP) in combination with estradiol (E2) on the breast in postmenopausal women. The objective of this study was to evaluate the effect of DRSP or norethisterone acetate (NETA) in continuous combination with E2 on two surrogate markers for breast cancer - mammographic breast density and proliferation of breast epithelial cells - in healthy postmenopausal women.

STUDY DESIGN

120 healthy, naturally postmenopausal women were randomized to either 2 mg of DRSP or 0.5 mg of NETA in continuous combination with 1 mg of oral E2. The women underwent mammography and fine-needle aspiration biopsy of the breast at baseline and after six months of treatment.

MAIN OUTCOME MEASURES

Digitized mammographic breast density and breast cell proliferation.

RESULTS

There was a significant increase in mammographic breast density after treatment in both groups (median increase 5.5% for E2/DRSP and 2.3% for E2/NETA, respectively, p < 0.001), but with no significant difference between groups. The proliferation of breast epithelial cells also increased in both groups (p < 0.001, respectively), with a significantly larger increase in the E2/DRSP group than in the E2/NETA group (2.5% versus 0.7%, respectively, p < 0.05). Systolic blood pressure had decreased significantly after 6 months of treatment in the E2/DRSP group (p < 0.05) but not in the E2/NETA group.

CONCLUSIONS

Breast density increased to a similar degree with E2/DRSP and E2/NETA. Proliferation of breast epithelial cells also increased significantly in both groups but was slightly more pronounced in the E2/DRSP group.

The insulin-like growth factor family and breast cancer prognosis: A prospective cohort study among postmenopausal women in Denmark

OBJECTIVE

Circulating levels of insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) have been associated with breast cancer (BC) risk. The evidence in relation to BC prognosis is limited. We aimed to evaluate the association between pre-diagnostic serum levels of IGF-I, IGF-II, IGFBP-2, IGFBP-3 and BC prognosis (i.e. recurrence, BC specific mortality and all-cause mortality) among women diagnosed with BC. We hypothesized that higher serum levels of IGFs and IGFBPs were associated with poor BC prognosis and that the associations were modified by estrogen receptor (ER) status.

DESIGN

From the Danish Diet, Cancer and Health cohort, 412 postmenopausal women diagnosed with incident BC within 5 years of cohort baseline (1993-1997) were identified. Baseline serum samples were analyzed for IGF-I, IGF-II, IGFBP-2 and IGFBP-3. Follow-up was carried out through 2014 by linkage to national Danish registries. Exposures were related to BC prognosis by Cox Proportional Hazard models; effect modification by ER status was investigated and sensitivity analyses by follow-up time were made.

RESULTS

During a median of 15 years, 106 women experienced recurrence and 172 died (118 due to BC). Overall, no associations were observed between IGF-I, IGF-II, IGFBP-2, IGFBP-3 and BC prognosis and no effect modification by ER status was observed. However, higher levels of IGF-II were associated with higher BC specific mortality [Hazard Ratio (HR) (95% Confidence Intervals (CI)): 1.43 (1.01-2.04)] within 10 years of follow-up. Likewise, higher levels of IGFBP-2 were associated with higher BC specific mortality [HR (95% CI): 1.87 (1.19-2.94)] within 5 years of follow-up. In contrast, higher levels of IGFBP-3 were associated with lower risk of recurrence [HR (95% CI): 0.76 (0.60-0.97)] at 5 years of follow-up and BC specific mortality [HR (95% CI): 0.80 (0.65-0.98)] within 10 years of follow-up.

CONCLUSIONS

The present study did not support an association between higher serum levels of IGFs, IGFBPs and adverse BC prognosis. However, it is possible that the role of the IGF family in the etiology of the 5-10 year BC prognosis is different from that of longer-term BC prognosis.

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.

Enhancement of mammary tumour growth by IGFBP-3 involves impaired T cell accumulation

Epidemiological studies show an association between obesity and poor breast cancer prognosis. We previously demonstrated that global IGFBP-3 deficiency, in IGFBP-3-null mice, resulted in a 50% reduction in mammary tumour growth over 3 weeks relative to tumours in wild-type (WT) C57BL/6 mice. This growth reduction was ameliorated by high fat feeding-induced obesity. This study aimed to examine how IGFBP-3 promotes tumour growth by influencing the immune tumour microenvironment in healthy and obese mice. Syngeneic EO771 cells, which lack detectable IGFBP-3 expression, were grown as orthotopic tumours in WT and IGFBP-3-null C57BL/6 mice placed on either a control chow or a high-fat diet (HFD), and examined by quantitative PCR and immunohistochemistry. In WT mice, increased stromal expression of IGFBP-3 was positively associated with tumour growth, supporting the hypothesis that IGFBP-3 in the microenvironment promotes tumour progression. Examining markers of immune cell subsets, gene expression of Ifng, Cd8a, Cd8b1 and Tnf and CD8 measured by immunohistochemistry were elevated in tumours of IGFBP-3-null mice compared to WT, indicating an accumulation of CD8+ T cells, but this increase was absent if the IGFBP-3-null mice had been exposed to HFD. Expression of these genes was negatively associated with tumour growth. Although similar among groups overall, Nkg2d and Tnfsf10 tumoural expression was associated with decreased tumour growth. Overall, the results of this study provide an immune-based mechanism by which host IGFBP-3 may promote breast tumour growth in the EO771 murine breast cancer model, and suggest that targeting IGFBP-3 might make a novel contribution to immune therapy for breast cancer.

Cardiometabolic risk factors and survival after breast cancer in the Women's Health Initiative

BACKGROUND

Few studies have examined the relationship between cardiometabolic risk factors linked to metabolic syndrome and mortality among women with breast cancer.

METHODS

We used the Women's Health Initiative to evaluate the relationship between cardiometabolic risk factors, including waist circumference (WC), blood pressure, cholesterol level, and presence of type 2 diabetes, and their relation with death from breast cancer, cardiovascular disease (CVD), and other causes among 8641 women with local or regional stage invasive breast cancer. Cox proportional hazards models were used to estimate hazard ratios, and 95% confidence intervals, adjusted for important predictors of survival.

RESULTS

After a median of 11.3 years, there were 2181 total deaths, 619 (28.4%) of which were due to breast cancer. Most participants (55.7%) had at least 2 cardiometabolic risk factors, and 4.9% had 3 or 4. Having a larger number of risk factors was associated with higher risk of CVD and other-cause mortality (P trend < .001 for both), but not with breast cancer mortality (P trend = .86). Increased WC was associated with a higher risk of CVD (hazard ratio [HR], 1.28; 95% confidence interval [CI], 1.05-1.57) and other-cause mortality (HR, 1.32; 95% CI, 1.16-1.49) and only with a small and nonsignificant higher risk of breast cancer mortality (HR, 1.19; 95% CI, 0.93-1.52). The results did not differ in analyses stratified by race, hormone receptor status, or after an analysis of cases diagnosed within 5 years after baseline.

CONCLUSIONS

Among women with early stage breast cancer, cardiometabolic risk factors are significantly associated with cardiovascular and other-cause mortality, but not breast cancer mortality. Cancer 2018;124:1798-807. © 2018 American Cancer Society.

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.

Could IGF-I levels play a neuroprotective role in patients with large vestibular schwannomas?

Aim

To evaluate the possible superiority of outcome in patients with elevated IGF-I levels after vestibular schwannoma (VS) resection.

Patients & methods

This retrospective study included 65 patients (34 male, 52.3%) with VS operated in between January 2009 and April 2014 (follow-up 3.2 ± 0.7 years). Preoperative or postoperative IGF-I levels were identified for each patient.

Results

Patients were divided into two groups: Group A (small size tumor), 56 patients; and Group B (large size tumor), 9 cases. IGF-I levels in Group A (195.8 ± 32.9 ng/ml) were compared with those of Group B (242.2 ± 22.2 ng/ml) and were found to have statistically significant difference (p = 0.001).

Conclusion

Increased IGF-I levels could hold a key role in nerve recovery in patients undergoing surgical resection of large VS.

Effects of a parallel-arm randomized controlled weight loss pilot study on biological and psychosocial parameters of overweight and obese breast cancer survivors

BACKGROUND

Weight gain often occurs after breast cancer (BC) diagnosis and obesity along with sedentary behavior are associated with increased risk of BC recurrence and mortality. The primary objective of this study was to determine whether a significant weight loss, of approximately 10%, would lead to beneficial changes in biomarkers associated with cancer and/or cancer recurrence, and quality of life (QOL) in overweight and obese BC survivors.

METHODS

This parallel-arm study took place in Minneapolis, Minnesota, from January 2009 until March 2010. Participants were overweight and obese postmenopausal BC survivors who had completed treatment at least 3 months prior to enrollment and who did not smoke. Twenty-one BC survivors were randomized, via a random number generator computer software, to a 1000-calorie deficit feeding and exercise intervention (CR) or a weight management counseling intervention (WM) for 12 weeks followed by a 6-week follow-up. Body weight, biomarkers, and QOL were measured at baseline, weeks 6, 12, and 18. Body composition and fitness level were measured at only two time points.

RESULTS

Twenty-one women were enrolled into the study and 20 completed all time points. Weight loss occurred with both interventions. Body weight in CR changed from 85.5 (95% confidence interval (CI) 77, 94) kg to 76.7 (95% CI 68.1, 85.2) kg, whereas in WM it changed from 98.3 (95% CI 89.8, 106.8) kg to 93.2 (95% CI 84.6, 101.7) kg. Fitness in CR changed from 4.9 (95% CI 4, 5.8) to 6.3 (95% CI 5.4, 7.2). CR led to lower plasma levels of leptin, F2-isoprostanes, and CRP. Quality of life seemed to improve with both interventions, while sleep quality decreased only in CR.

CONCLUSIONS

Overweight and obese BC survivors were able to adhere to a strict diet and exercise program, which significantly decreased body weight, increased fitness level, and improved biomarkers and QOL. However, the strict dietary intervention in CR seemed to decrease participants' sleep quality and social relationships. Future larger randomized controlled trials should focus on behavioral modification and personalized nutrition counseling to help breast cancer survivors achieve a sustainable weight loss and fitness level.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02940470.

The insulin-like growth factor system is modulated by exercise in breast cancer survivors: a systematic review and meta-analysis

Background

Insulin-like growth factors (IGF´s) play a crucial role in controlling cancer cell proliferation, differentiation and apoptosis. Exercise has been postulated as an effective intervention in improving cancer-related outcomes and survival, although its effects on IGF´s are not well understood. This meta-analysis aimed to determine the effects of exercise in modulating IGF´s system in breast cancer survivors.

Methods

Databases of PuMed, EMBASE, Cochrane Central Register of Controlled Trials, EMBASE, ClinicalTrials.gov, SPORTDiscus, LILACS and Scopus were systematically searched up to November 2014. Effect estimates were calculated through a random-effects model of meta-analysis according to the DerSimonian and Laird method. Heterogeneity was evaluated with the I² test. Risk of bias and methodological quality were evaluated using the PEDro score.

Results

Five randomized controlled trials (n = 235) were included. Most women were post-menopausal. High-quality and low risk of bias were found (mean PEDro score = 6.2 ± 1). Exercise resulted in significant improvements on IGF-I, IGF-II, IGFBP-I, IGFBP-3, Insulin and Insulin resistance (P < 0.05). Non-significant differences were found for Glucose. Aerobic exercise improved IGF-I, IGFBP-3 and Insulin. No evidence of publication bias was detected by Egger´s test (p = 0.12).

Conclusions

Exercise improved IGF´s in breast cancer survivors. These findings provide novel insight regarding the molecular effects of exercise on tumoral microenvironment, apoptosis and survival in breast cancer survivors.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2733-z) contains supplementary material, which is available to authorized users.

Relapse profile of early breast cancer according to immunohistochemical subtypes: guidance for patient's follow up?

PURPOSE

To analyze the profile of annual recurrence rate (ARR) of patients with early breast cancer (BC) in Tunisia.

PATIENTS AND METHODS

We classified 293 patients with histologically confirmed early BC relapsing after 1 year of follow up into three subgroups: hormone receptor (HR)+ 'HR' [estrogen receptor (ER)+ or progesterone receptor (PR)+ and human epidermal growth factor receptor 2 (HER2)-], triple negative 'TN' (ER-, PR- and HER2 score 0/1 or fluorescence in situ hybridization (FISH)/chromogenic in situ hybridization negative) and HER2 overexpression 'HER2' (HER2+). ARR was restricted to follow-up contribution of each specified time interval. The HR group was the reference group for comparison.

RESULTS

A higher proportion of patients who were up to 35 years old (18% versus 10%, p = 0.04), and patients with obesity (46% versus 26%, p = 0.045) was seen in the TN group. Median time to relapse (MTR) was shorter in TN and HER2 groups than in HR patients (20 and 29 months compared with 56 months, respectively, p < 0.001). In the HR group, the ARR was 22%, 16% and 10% at 3, 4 and 5 years respectively, becoming less than 3% at 7 years. In the TN group, 71% of patients relapsed during the first 2 years and the ARR declined rapidly to less than 1.5% after 4 years. In the HER2 group, the ARR peaked at 2 years (29%) and decreased significantly to 7% and 3% at 5 and 7 years respectively. Adjuvant trastuzumab delayed the MTR from 24 to 34 months (p = 0.022).

CONCLUSION

The relapse risk in Tunisian patients is higher in young women and patients with HER2+ and TN tumors. A long and close follow up is recommended for patients with HR and HER2. Conversely, we suggest that follow up in patients with TN could be spaced after 4 years (ARR being <1.5% after this period).

Physiology and pathophysiology of IGFBP-1 and IGFBP-2 - consensus and dissent on metabolic control and malignant potential

IGFBP-1 and IGFBP-2 are suppressed by growth hormone and therefore represent less prominent members of the IGFBP family when compared to IGFBP-3 that carries most of the IGFs during circulation under normal conditions in humans in vivo. As soon as the GH signal is decreased expression of IGF-I and IGFBP-3 is reduced. Under conditions of lowered suppression by GH the time seems come for IGFBP-1 and IGFBP-2. Both IGFBPs are potent effectors of growth and metabolism. Secretion of IGFBP-1 and IGFBP-2 is further suppressed by insulin and diminished with increasing obesity. Both IGFBP family members share the RGD sequence motif that mediates binding to integrins and is linked to PTEN/PI3K signalling. In mice, IGFBP-2 prevents age- and diet-dependent glucose insensitivity and blocks differentiation of preadipocytes. The latter function is modulated by two distinct heparin-binding domains of IGFBP-2 which are lacking in IGFBP-1. IGFBP-2 is further regulated by leptin and has been demonstrated to affect insulin sensitivity and glucose tolerance, further supporting a particular role of IGFBP-2 in glucose and fat metabolism. Since IGFBP-2 is controlled by sex steroids as well, we devised a scheme to compare IGFBP effects in breast, ovarian and prostate cancer. While a positive association does not seem to exist with IGFBP-1 and risk of cancers within these reproductive tissues, a relationship between IGFBP-2 and breast cancer, ovarian cancer and prostate cancer does indeed appear to be present. To date, the specific roles of IGFBP-2 in estrogen signalling are unclear, though there is accumulating evidence for an effect of IGFBP-2 on PI3K signalling via PTEN, particularly in breast cancer.

Weight Gain After Breast Cancer Diagnosis and All-Cause Mortality: Systematic Review and Meta-Analysis

BACKGROUND

Overweight and obesity are associated with breast cancer mortality. However, the relationship between postdiagnosis weight gain and mortality is unclear. We conducted a systematic review and meta-analysis of weight gain after breast cancer diagnosis and breast cancer-specific, all-cause mortality and recurrence outcomes.

METHODS

Electronic databases identified articles up through December 2014, including: PubMed (1966-present), EMBASE (1974-present), CINAHL (1982-present), and Web of Science. Language and publication status were unrestricted. Cohort studies and clinical trials measuring weight change after diagnosis and all-cause/breast cancer-specific mortality or recurrence were considered. Participants were women age 18 years or older with stage I-IIIC breast cancer. Fixed effects analysis summarized the association between weight gain (≥5.0% body weight) and all-cause mortality; all tests were two-sided.

RESULTS

Twelve studies (n = 23 832) were included. Weight gain (≥5.0%) compared with maintenance (<±5.0%) was associated with increased all-cause mortality (hazard ratio [HR] = 1.12, 95% confidence interval [CI] = 1.03 to 1.22, P = .01, I(2) = 55.0%). Higher risk of mortality was apparent for weight gain ≥10.0% (HR = 1.23, 95% CI = 1.09 to 1.39, P < .001); 5% to 10.0% weight gain was not associated with all-cause mortality (P = .40). The association was not statistically significant for those with a prediagnosis body mass index (BMI) of less than 25 kg/m(2) (HR = 1.14, 95% CI = 0.99 to 1.31, P = .07) or with a BMI of 25 kg/m(2) or higher (HR = 1.00, 95% CI = 0.86 to 1.16, P = .19). Weight gain of 10.0% or more was not associated with hazard of breast cancer-specific mortality (HR = 1.17, 95% CI = 1.00 to 1.38, P = .05).

CONCLUSIONS

Weight gain after diagnosis of breast cancer is associated with higher all-cause mortality rates compared with maintaining body weight. Adverse effects are greater for weight gains of 10.0% or higher.

The integrative role of leptin, oestrogen and the insulin family in obesity-associated breast cancer: potential effects of exercise

Obesity is an established risk factor for postmenopausal breast cancer. The mechanisms through which obesity influences the development and progression of breast cancer are not fully elucidated; however, several factors such as increased oestrogen, concentrations of various members of the insulin family and inflammation that are associated with adiposity are purported to be important factors in this relationship. Emerging research has also begun to focus on the role of adipokines, (i.e. adipocyte secreted factors), in breast cancer. Leptin secretion is directly related to adiposity and is believed to promote breast cancer directly and independently, as well as through involvement with the oestrogen and insulin signalling pathways. As leptin is secreted from white adipose tissue, any intervention that reduces adiposity may be favourable. However, it is also important to consider that energy expenditure through exercise, independent of fat loss, may improve leptin regulation. The purpose of this narrative review was to explore the role of leptin in breast cancer development and progression, identify key interactions with oestrogen and the insulin family, and distinguish the potential effects of exercise on these interactions.

Differences in IGF-axis protein expression and survival among multiethnic breast cancer patients

There is limited knowledge about the biological basis of racial/ethnic disparities in breast cancer outcomes. Aberrations in IGF signaling induced by obesity and other factors may contribute to these disparities. This study examines the expression profiles of the insulin-like growth factor (IGF)-axis proteins and the association with breast cancer survival across a multiethnic population. We examined the expression profiles of the IGF1, IGF1R, IGFBP2 (IGF-binding proteins), and IGFBP3 proteins in breast tumor tissue and their relationships with all-cause and breast cancer-specific survival up to 17 years postdiagnosis in a multiethnic series of 358 patients in Hawaii, USA. Native Hawaiians, Caucasians, and Japanese were compared. Covariates included demographic and clinical factors and ER/PR/HER2 (estrogen receptor/progesterone receptor/human epidermal growth factor receptor-2) status. In Native Hawaiian patients, IGFBP2 and IGFBP3 expression were each independently associated with overall and breast cancer mortality (IGFB2: HR_mort = 10.96, 95% CI: 2.18–55.19 and HR_mort = 35.75, 95% CI: 3.64–350.95, respectively; IGFBP3: HR_mort = 5.16, 95% CI: 1.27–20.94 and HR_mort = 8.60, 95% CI: 1.84–40.15, respectively). IGF1R expression was also positively associated with all-cause mortality in Native Hawaiians. No association of IGF-axis protein expression and survival was observed in Japanese or Caucasian patients. The interaction of race/ethnicity and IGFBP3 expression on mortality risk was significant. IGF-axis proteins may have variable influence on breast cancer progression across different racial/ethnic groups. Expression of binding proteins and receptors in breast tumors may influence survival in breast cancer patients by inducing aberrations in IGF signaling and/or through IGF-independent mechanisms. Additional studies to evaluate the role of the IGF-axis in breast cancer are critical to improve targeted breast cancer treatment strategies.

Obesity enhances nongenomic estrogen receptor crosstalk with the PI3K/Akt and MAPK pathways to promote in vitro measures of breast cancer progression

Introduction

Epidemiological and clinical studies indicate that obesity is associated with a worse postmenopausal breast cancer prognosis and an increased risk of endocrine therapy resistance. However, the mechanisms mediating these effects remain poorly understood. Here we investigate the molecular pathways by which obesity-associated circulating factors in the blood enhance estrogen receptor alpha (ERα) positive breast cancer cell viability and growth.

Methods

Blood serum was collected from postmenopausal breast cancer patients and pooled by body mass index (BMI) category (Control: 18.5 to 24.9 kg/m²; Obese: ≥30.0 kg/m²). The effects of patient sera on MCF-7 and T47D breast cancer cell viability and growth were examined by MTT and colony formation assays, respectively. Insulin-like growth factor receptor 1(IGF-1R), Akt, and ERK1/2 activation and genomic ERα activity were assessed to determine their possible contribution to obese patient sera-induced cell viability and growth. To further define the relative contribution of these signaling pathways, cells grown in patient sera were treated with various combinations of ERα, PI3K/Akt and MAPK targeted therapies. Comparisons between cells exposed to different experimental conditions were made using one-way analysis of variance (ANOVA) and Student's t test.

Results

Cells grown in media supplemented with obese patient sera displayed greater cell viability and growth as well as IGF-1R, Akt and ERK1/2 activation relative to control sera. Despite the lack of a significant difference in genomic ERα activity following growth in obese versus control patient sera, we observed a dramatic reduction in cell viability and growth after concurrent inhibition of the ERα and PI3K/Akt signaling pathways. Further, we demonstrated that ERα inhibition was sufficient to attenuate obese serum-induced Akt and ERK1/2 activation. Together, these data suggest that obesity promotes greater ERα positive breast cancer cell viability and growth through enhanced crosstalk between nongenomic ERα signaling and the PI3K/Akt and MAPK pathways.

Conclusions

Circulating factors in the serum of obese postmenopausal women stimulate ERα positive breast cancer cell viability and growth by facilitating non-genomic ERα crosstalk with the PI3K/Akt and MAPK signaling pathways. These findings provide valuable insight into one mechanism by which obesity may promote ERα positive postmenopausal breast cancer progression and endocrine therapy resistance.

Lactose intolerance and risk of lung, breast and ovarian cancers: aetiological clues from a population-based study in Sweden

Background:

Individuals with lactose intolerance are recommended to avoid milk or dairy products, which may affect the development of cancer.

Methods:

We identified individuals with lactose intolerance from several Swedish Registers linked to the Swedish Cancer Registry to calculate standardised incidence ratios (SIRs) for cancers in the breast, lung, and ovary.

Results:

A total of 22 788 individuals with lactose intolerance were identified, and their risks of lung (SIR=0.55), breast (SIR=0.79), and ovarian (SIR=0.61) cancers were significantly decreased. Cancer incidences in the siblings and parents of individuals with lactose intolerance were similar to those in the general population.

Conclusions:

In this large cohort study, people with lactose intolerance, characterised by low consumption of milk and other dairy products, had decreased risks of lung, breast, and ovarian cancers, but the decreased risks were not found in their family members, suggesting that the protective effects against these cancers may be related to their specific dietary pattern.

Molecular pathways: preclinical models and clinical trials with metformin in breast cancer

Metformin, an oral biguanide widely used to treat diabetes, has considerable potential and is in clinical trials as an experimental preventive or therapeutic agent for a range of cancers. Direct actions targeting cellular pathways, particularly via AMP-activated protein kinase and through inhibiting mitochondrial ATP synthesis, or systemic mechanisms involving insulin and insulin-like growth factors have been much studied in vitro and in preclinical models. Epidemiologic and retrospective studies also provide clinical evidence in support of metformin as an antitumor agent. Preoperative window-of-opportunity trials confirm the safety of metformin in women with primary breast cancer, and demonstrate reduction in tumor cell proliferation and complex pathways of gene suppression or overexpression attributable to metformin. Confirmation of insulin-mediated effects, independent of body mass index, also supports the potential benefit of adjuvant metformin therapy. Neoadjuvant, adjuvant, and advanced disease trials combining metformin with established anticancer agents are under way or proposed. Companion biomarker studies will utilize in vitro and preclinical understanding of the relevant molecular pathways to, in future, refine patient and tumor selection for metformin therapy.

Clinical studies examining the impact of obesity on breast cancer risk and prognosis

Obesity is associated with an increased risk of breast cancer, and increased risk of recurrence in women who develop breast cancer. Evidence suggests that the risk of estrogen-receptor (ER)-positive breast cancer is increased in obese postmenopausal women, whereas in premenopausal women the risk of triple negative breast cancer is increased. Nonetheless, the presence of obesity at diagnosis, and possibly weight gain after diagnosis, may independently contribute to an individual's risk of recurrence of both pre- and postmenopausal breast cancer. Factors associated with adiposity that are likely contributing factors include hyperinsulinemia, inflammation, and relative hyperestrogenemia. Some studies suggest that some aromatase inhibitors may be less effective in obese women than lean women. Clinical trials have evaluated pharmacologic (eg, metformin) and dietary/lifestyle interventions to reduce breast cancer recurrence, although these interventions have not been tested in obese women who may be most likely to benefit from them. Further research is required in order to identify adiposity-associated factors driving recurrence, and design clinical trials to specifically test interventions in obese women at highest risk of recurrence.

Primary breast cancer stem-like cells metastasise to bone, switch phenotype and acquire a bone tropism signature

BACKGROUND

Bone metastases represent a common and severe complication in breast cancer, and the involvement of cancer stem cells (CSCs) in the promotion of bone metastasis is currently under discussion. Here, we used a human-in-mice model to study bone metastasis formation due to primary breast CSCs-like colonisation.

METHODS

Primary CD44⁺CD24⁻ breast CSCs-like were transduced by a luciferase-lentiviral vector and injected through subcutaneous and intracardiac (IC) routes in non-obese/severe-combined immunodeficient (NOD/SCID) mice carrying subcutaneous human bone implants. The CSCs-like localisation was monitored by in vivo luciferase imaging. Bone metastatic CSCs-like were analysed through immunohistochemistry and flow cytometry, and gene expression analyses were performed by microarray techniques.

RESULTS

Breast CSCs-like colonised the human-implanted bone, resulting in bone remodelling. Bone metastatic lesions were histologically apparent by tumour cell expression of epithelial markers and vimentin. The bone-isolated CSCs-like were CD44⁻CD24⁺ and showed tumorigenic abilities after injection in secondary mice. CD44⁻CD24⁺ CSCs-like displayed a distinct bone tropism signature that was enriched in genes that discriminate bone metastases of breast cancer from metastases at other organs.

CONCLUSION

Breast CSCs-like promote bone metastasis and display a CSCs-like bone tropism signature. This signature has clinical prognostic relevance, because it efficiently discriminates osteotropic breast cancers from tumour metastases at other sites.

The role of chronic inflammation in obesity-associated cancers

There is a strong relationship between metabolism and immunity, which can become deleterious under conditions of metabolic stress. Obesity, considered a chronic inflammatory disease, is one example of this link. Chronic inflammation is increasingly being recognized as an etiology in several cancers, particularly those of epithelial origin, and therefore a potential link between obesity and cancer. In this review, the connection between the different factors that can lead to the chronic inflammatory state in the obese individual, as well as their effect in tumorigenesis, is addressed. Furthermore, the association between obesity, inflammation, and esophageal, liver, colon, postmenopausal breast, and endometrial cancers is discussed.

Age and the effect of physical activity on breast cancer survival: A systematic review

The effect of physical activity (PA) on cancer survival is still the topic of debate in oncology research focusing on survivorship, and has been investigated retrospectively in several large clinical trials. PA has been shown to improve quality of life, fitness and strength, and to reduce depression and fatigue. At present, there is a growing body of evidence on the effects of PA interventions for cancer survivors on health outcomes. PA and functional limitations are interrelated in the elderly. However the relationship between breast cancer survival and PA in older breast cancer patients has not yet been fully investigated. Our systematic review of the existing literature on this topic yielded seventeen studies. Most reports demonstrated an improved overall and breast cancer-specific survival. Furthermore, in studies that compared younger women with older or postmenopausal women, it was suggested that the beneficial effect of PA may be even greater in older women. Understanding the interaction between physical functioning and cancer survival in older breast cancer patients is key, and may contribute to successful treatment and survival. In this population of cancer survivors it is therefore imperative to embark on research focused on improving physical functioning in the context of comorbidities and functional limitations.

Effect of body mass index on tumor characteristics and disease-free survival in patients from the HER2-positive adjuvant trastuzumab trial N9831

BACKGROUND

Data suggest that weight, and specifically body mass index (BMI), plays a role in breast cancer development and outcome. The authors hypothesized that there would be a correlation between BMI and clinical outcome in patients with early stage, human epidermal receptor 2 (HER2)-positive breast cancer enrolled in the N9831 adjuvant trial.

METHODS

Patients were grouped according to baseline BMI as follows: normal (BMI <25 kg/m(2)), overweight (BMI ≥25 kg/m(2) and <30 kg/m(2)), and obese (BMI ≥30 kg/m(2)). Disease-free survival (DFS) was estimated using the Kaplan-Meier method. Comparisons between treatment arms A, B, and C (chemotherapy with or without trastuzumab) were performed using a stratified Cox proportional hazards model.

RESULTS

Analysis was completed on 3017 eligible patients. Obese patients were more likely to be older and postmenopausal (P < .0001 for both), to have larger tumors (P = .002), and to have positive lymph nodes (P = .004). In the pooled analysis cohort, differences in DFS among the BMI groups were statistically significant (5-year DFS rate: 82.5%, 78.6%, and 78.5% for normal weight, overweight, and obese women, respectively; log-rank P = .02). The adjusted hazard ratio comparing the DFS of overweight women with the DFS of normal women was 1.30 (95% confidence interval, 1.06-1.61); and, comparing the DFS of obese women with the DFS normal women, the adjusted hazard ratio was 1.31 (95% confidence interval, 1.07-1.59). There were no statistically significant differences in DFS by weight group for women within any trial arm.

CONCLUSIONS

Patients with early stage, HER2-positive breast cancer and normal BMI had a better 5-year DFS compared with overweight and obese women. The current results indicated that adjuvant trastuzumab improves clinical outcome regardless of BMI.

Associations of insulin-like growth factor and insulin-like growth factor binding protein-3 with mortality in women with breast cancer

Elevated circulating insulin-like growth factor-1 (IGF-1), a breast epithelial cell mitogen, is associated with breast cancer development. However, its association with breast cancer survival is not established. Circulating concentrations of IGF-1 are controlled via binding proteins, including IGF Binding Protein-3 (IGFBP-3), that may modulate the association of IGF-1 with breast-cancer outcomes. We measured IGF-1 and IGFBP-3 concentrations in serum from 600 women enrolled in the health, eating, activity, and lifestyle (HEAL) study, a multiethnic, prospective cohort study of women diagnosed with stage I-IIIA breast cancer. We evaluated the association between IGF-1 and IGFBP-3, and as a ratio, modeled using quintile cut-points, with risk of breast cancer-specific (n = 42 deaths) and all-cause mortality (n = 87 deaths) using Cox proportional hazards models. In models adjusted for body mass index, ethnicity, tamoxifen use at time of blood draw, treatment received at diagnosis and IGFBP-3, women in the highest quintile of IGF-1 level had an increased risk of all-cause mortality (Hazard Ratio (HR) = 3.10, 95% CI 1.21-7.93, p = 0.02), although no dose-response association was evident. The IGF-1/IGFBP-3 ratio, an indicator of free IGF-I levels, was significantly associated with increasing risk of all-cause mortality (HR = 2.83, 95% CI 1.25-6.36 p(trend) = 0.01, upper vs. lower quintile) in a fully adjusted model. In conclusion, high serum levels of IGF-1 and the IGF-1/IGFBP-3 ratio were associated with increased risk of all-cause mortality in women with breast cancer. These results need to be confirmed in larger breast cancer survivor cohorts.

Importance of metabolic changes induced by chemotherapy on prognosis of early-stage breast cancer patients: a review of potential mechanisms

Weight variation has been reported as a side effect of chemotherapy treatment in early breast cancer patients and has been identified as a factor of poor prognosis. Causes of weight variation during chemotherapy and mechanisms involved in the poor prognosis have been little studied. Here is reviewed the current knowledge about the main causes and mechanisms involved in body weight change. Special emphasis is placed on factors associated with weight variation which could potentially be involved in the risk of relapse in breast cancer survivors. In recent decades, some studies have investigated the causes of weight variation by studying energy balance of breast cancer patients during chemotherapy. Weight gain or loss may be the consequence of energy imbalance through different factors linked with chemotherapy, such as poor treatment tolerance, decreased muscle mass and function, or hormonal alterations. This results in body composition modifications in favour of fat gain and/or lean body mass loss. Increased adipose tissue, especially in the abdominal region, could induce metabolic disturbances such as insulin resistance, through various pathways involving adipokines. These molecules have growth properties and could therefore play a role in cancer relapse. Understanding such mechanisms is key to developing preventive strategies for improving the prognosis of early-stage breast cancer patients.

Bootcamp during neoadjuvant chemotherapy for breast cancer: a randomized pilot trial

Introduction

Exercise may improve cancer outcomes. Neoadjuvant chemotherapy (NC) for breast cancer provides a unique setting to evaluate intervention effects. Treatments leading to decreased post-neoadjuvant Ki-67 levels, smaller tumor size, and higher pathologic response are associated with improved survival and lower recurrence. This randomized, prospective pilot trial evaluates the feasibility of supervised exercise during NC for breast cancer.

Methods

Stage II-III, ER positive, cancer patients with BMI > 25 receiving NC were randomized to standard NC with supervised bootcamp (NC + BC) or NC alone. Ki-67, C-peptide, BMI, and tumor size were measured before chemotherapy and at time of surgery.

Results

There were no initial differences between groups in regards to tumor size, C-peptide, BMI, and Ki–67. The NC + BC (n = 5) group had a lower mean BMI at the conclusion of NC compared with those (n = 5) in the NC group (28.0 versus 35.8, P = 0.03). Final tumor size was 2.59 cm in the NC + BC group versus 3.16 cm for NC (P = 0.76) Mean Ki-67 for NC + BC was 7% versus 29% with NC (P = 0.14). C-peptide (ng/mL) was equivalent between the two groups (4.55 NC + BC versus 4.74 NC, P = 0.85).

Conclusions

Adding a supervised exercise program to NC is feasible, decreases BMI, and may lead to lower Ki-67 levels and improved survival.

Insulin- and obesity-related variables in early-stage breast cancer: correlations and time course of prognostic associations

PURPOSE

To investigate patterns of prognostic associations over time of insulin- and obesity-related variables measured at diagnosis of early breast cancer (BC), focusing on whether the prognostic associations with distant recurrence and death changed over time.

PATIENTS AND METHODS

Five hundred thirty-five nondiabetic women with T1-3, N0-1, M0 invasive BC diagnosed from 1989 to 1996 were included in the study. Insulin-related variables included fasting insulin, Homeostasis Model Assessment, C-peptide, and glucose. Obesity-related variables included weight, body mass index (BMI), waist and hip circumference, and leptin. Correlations were examined using the Pearson correlation coefficient and prognostic associations using the Cox model.

RESULTS

There was evidence that associations of baseline insulin-related variables with distant recurrence and death were not constant over time; univariable adverse prognostic associations were significant only during the first 5 years (eg, insulin quartile 4 v 1: hazard ratio [HR], 2.32; 95% CI, 1.39 to 3.86; P < .001 for distant disease-free survival [DDFS]; and HR, 2.85; 95% CI, 1.48 to 5.50; P = .002 for overall survival [OS], with little attenuation of this pattern in multivariable analyses). In contrast, obesity-related variables (BMI, weight, leptin) exerted significant adverse univariable associations that were constant over time (eg, BMI quartile 4 v 2: HR, 1.40; 95% CI, 1.07 to 1.82 for DDFS; P = .014; and HR, 1.50; 95% CI, 1.16 to 1.93; P < .001 for OS); prognostic associations of leptin remained significant in multivariable analyses.

CONCLUSION

Baseline insulin- and obesity-related variables exert different patterns of prognostic associations over time in early BC.

Is there a role for carbohydrate restriction in the treatment and prevention of cancer?

Over the last years, evidence has accumulated suggesting that by systematically reducing the amount of dietary carbohydrates (CHOs) one could suppress, or at least delay, the emergence of cancer, and that proliferation of already existing tumor cells could be slowed down. This hypothesis is supported by the association between modern chronic diseases like the metabolic syndrome and the risk of developing or dying from cancer. CHOs or glucose, to which more complex carbohydrates are ultimately digested, can have direct and indirect effects on tumor cell proliferation: first, contrary to normal cells, most malignant cells depend on steady glucose availability in the blood for their energy and biomass generating demands and are not able to metabolize significant amounts of fatty acids or ketone bodies due to mitochondrial dysfunction. Second, high insulin and insulin-like growth factor (IGF)-1 levels resulting from chronic ingestion of CHO-rich Western diet meals, can directly promote tumor cell proliferation via the insulin/IGF1 signaling pathway. Third, ketone bodies that are elevated when insulin and blood glucose levels are low, have been found to negatively affect proliferation of different malignant cells in vitro or not to be usable by tumor cells for metabolic demands, and a multitude of mouse models have shown anti-tumorigenic properties of very low CHO ketogenic diets. In addition, many cancer patients exhibit an altered glucose metabolism characterized by insulin resistance and may profit from an increased protein and fat intake.

In this review, we address the possible beneficial effects of low CHO diets on cancer prevention and treatment. Emphasis will be placed on the role of insulin and IGF1 signaling in tumorigenesis as well as altered dietary needs of cancer patients.

Effect of a low fat versus a low carbohydrate weight loss dietary intervention on biomarkers of long term survival in breast cancer patients ('CHOICE'): study protocol

Background

Weight loss in overweight or obese breast cancer patients is associated with an improved prognosis for long term survival. However, it is not clear whether the macronutrient composition of the chosen weight loss dietary plan imparts further prognostic benefit. A study protocol is presented for a dietary intervention to investigate the effects of weight loss dietary patterns that vary markedly in fat and carbohydrate contents on biomarkers of exposure to metabolic processes that may promote tumorigenesis and that are predictive of long term survival. The study will also determine how much weight must be lost for biomarkers to change in a favorable direction.

Methods/Design

Approximately 370 overweight or obese postmenopausal breast cancer survivors (body mass index: 25.0 to 34.9 kg/m²) will be accrued and assigned to one of two weight loss intervention programs or a non-intervention control group. The dietary intervention is implemented in a free living population to test the two extremes of popular weight loss dietary patterns: a high carbohydrate, low fat diet versus a low carbohydrate, high fat diet. The effects of these dietary patterns on biomarkers for glucose homeostasis, chronic inflammation, cellular oxidation, and steroid sex hormone metabolism will be measured. Participants will attend 3 screening and dietary education visits, and 7 monthly one-on-one dietary counseling and clinical data measurement visits in addition to 5 group visits in the intervention arms. Participants in the control arm will attend two clinical data measurement visits at baseline and 6 months. The primary outcome is high sensitivity C-reactive protein. Secondary outcomes include interleukin-6, tumor necrosis factor-α, insulin-like growth factor-1 (IGF), IGF binding protein-3, 8-isoprostane-F2-alpha, estrone, estradiol, progesterone, sex hormone binding globulin, adiponectin, and leptin.

Discussion

While clinical data indicate that excess weight for height is associated with poor prognosis for long term survival, little attention is paid to weight control in the clinical management of breast cancer. This study will provide information that can be used to answer important patient questions about the effects of dietary pattern and magnitude of weight loss on long term survival following breast cancer treatment.

Clinical Trial Registration

CA125243

Visceral adiposity, insulin resistance and cancer risk

BACKGROUND

There is a well established link between obesity and cancer. Emerging research is characterising this relationship further and delineating the specific role of excess visceral adiposity, as opposed to simple obesity, in promoting tumorigenesis. This review summarises the evidence from an epidemiological and pathophysiological perspective.

METHODS

Relevant medical literature was identified from searches of PubMed and references cited in appropriate articles identified. Selection of articles was based on peer review, journal and relevance.

RESULTS

Numerous epidemiological studies consistently identify increased risk of developing carcinoma in the obese. Adipose tissue, particularly viscerally located fat, is metabolically active and exerts systemic endocrine effects. Putative pathophysiological mechanisms linking obesity and carcinogenesis include the paracrine effects of adipose tissue and systemic alterations associated with obesity. Systemic changes in the obese state include chronic inflammation and alterations in adipokines and sex steroids. Insulin and the insulin-like growth factor axis influence tumorigenesis and also have a complex relationship with adiposity. There is evidence to suggest that insulin and the IGF axis play an important role in mediating obesity associated malignancy.

CONCLUSIONS

There is much evidence to support a role for obesity in cancer progression, however further research is warranted to determine the specific effect of excess visceral adipose tissue on tumorigenesis. Investigation of the potential mechanisms underpinning the association, including the role of insulin and the IGF axis, will improve understanding of the obesity and cancer link and may uncover targets for intervention.

Physical activity and cancer prevention: a systematic review of clinical trials

BACKGROUND

Physically active individuals have lower rates of many cancers and improved cancer outcomes. Controlled exercise trials measuring putative biomarkers of cancer risk are being conducted to further understand the role of exercise in cancer etiology and progression. We aimed to systematically review the effect of exercise on various biomarkers.

METHODS

A comprehensive search strategy identified 353 publications from January 1980 to August 2010. We included those clinical trials of exercise measuring biomarkers following minimum 4-week intervention among cancer survivors or people with one or more cancer risk factors. Two reviewers abstracted data and assessed quality independently. Effect sizes and 95% confidence intervals were estimated.

RESULTS

Four primary prevention and five tertiary prevention trials were included. Exercise had a small to moderate effect on improving concentrations of several blood biomarkers implicated in breast and colon cancer pathways including insulin, leptin, estrogens, and apoptosis regulation. In breast cancer survivors, exercise had a small to moderate effect on improving some biomarkers associated with prognosis including various insulin-like growth factor axis proteins, insulin, and inflammation; and a large effect on enhancing immune function.

CONCLUSION

Data are few, but there is some evidence to support the role of exercise in modulating various cancer pathways.

Recommendations for a lifestyle which could prevent breast cancer and its relapse: physical activity and dietetic aspects

External factors such as eating habits and physical activity have an important impact on breast cancer risk. This paper reviews the literature on the relationship between breast cancer and lifestyle. It aims to produce recommendations regarding physical activity and dietary intake for clinical practice. Although strong clinical evidence of the impact of lifestyle modifications is still lacking, practising healthy eating should be encouraged for the prevention of cancer, its occurrence or relapse. Physical activity is recommended to avoid excessive weight gain. For example, the beneficial effects on the risk of breast cancer could be achieved by walking half an hour per day. Three to five hours per week of moderate physical exercise therefore should be recommended for optimising the reduction of the risk of cancer. For most women, moderate to intense activity, such as heavy housework, brisk walking, or dancing, could provide an effective level of activity to keep reduce the risk of breast cancer.

Insulin-like growth factor binding protein-3 (IGFBP-3) gene variants are associated with renal cell carcinoma

OBJECTIVE

• To evaluate the A to C nucleotide change located 202 bp upstream to the transcription start site, (-202 A/C polymorphism), in the insulin-like growth factor (IGF) binding protein-3 (IGFBP-3) gene, and its association with renal carinogenesis and with clinicopathological characteristics.

PATIENTS AND METHODS

• We matched 158 male patients with clear-cell renal cell carcinoma (CCRCC) to 316 healthy controls, and genotyped one single nucleotide polymorphism (rs2854744) using the polymerase chain reaction restriction fragment length polymorphism technique.

RESULTS

• The alleles and genotypes differed significantly between patients with CCRCC and controls (patients with CCRCC, P= 0.82; controls, P= 0.88). • We found that the frequency of the AA genotype was significantly higher in patients with CCRCC than in controls (odds ratio [OR]= 4.62, 95% confidence interval [CI]= 3.41-7.42, P= 0.001). • The A allele had a gene dose effect in increasing the risk of CCRCC (OR = 4.75, 95% CI = 3.64-7.64, P= 0.001). • The distribution of IGFBP-3 genotypes was also significantly associated with the histological grade (P= 0.001) and clinical stage (P= 0.001).

CONCLUSION

• In the Iranian population, the polymorphism of the IGFBP-3 gene plays a pivotal role in the development of CCRCC.

Biological mechanisms linking obesity and cancer risk: new perspectives

Body mass index, as an approximation of body adiposity, is associated with increased risk of several common and less common malignancies in a sex- and site-specific manner. These findings implicate sex- and cancer site-specific biological mechanisms underpinning these associations, and it is unlikely that there is a "one system fits all" mechanism. Three main candidate systems have been proposed-insulin and the insulin-like growth factor-I axis, sex steroids, and adipokines-but there are shortfalls to these hypotheses. In this review, three novel candidate mechanisms are proposed: obesity-induced hypoxia, shared genetic susceptibility, and migrating adipose stromal cells. While public health policies aimed at curbing the underlying causes of the obesity epidemic are being implemented, there is a parallel need to better understand the biological processes linking obesity and cancer as a prerequisite to the development of new approaches to prevention and treatment.

IGF-1, IGFBP-3 and ALS in adult patients with chronic kidney disease

BACKGROUND

Insulin-like growth factor I (IGF-1) is for the most part bound in a ternary complex with IGF-binding protein-3 (IGFBP-3) and acid-labile subunit (ALS). This ternary complex is a storage form of IGF-1 in blood and passes not through the renal glomerulus. Little information is available in regard to the components of the ternary complex in adult renal disease.

OBJECTIVE

To investigate levels of serum IGF-1, IGFBP-3 and ALS in relation to renal function and extent of proteinuria.

DESIGN AND PATIENTS

We measured IGF-1, IGFBP-3 and ALS concentrations in 137 patients who were investigated due to proteinuria and/or haematuria and/or renal impairment. The patients received renal biopsies and the histological diagnosis was documented. Urinary albumin excretion and relevant clinical parameter were evaluated.

RESULTS

IGF-1 showed a highly positive correlation to IGFBP-3 and ALS, and the latter to IGFBP-3. IGF-1, IGFBP-3 and ALS decreased with increasing age. IGF-1 and IGFBP-3 showed no significant change depending on the creatinine clearance. However, ALS decreased with decreasing renal function. In patients with heavy proteinuria ALS levels, but not IGF-1 and IGFBP-3 levels, decreased significantly. Patients with chronic ischaemic renal damage and diabetic glomerulopathy showed higher IGF-1 and IGFBP-3 levels compared to patients with thin glomerular basement membrane disease despite their older age.

CONCLUSIONS

IGF-1 and IGFBP-3 levels seem to be independent of renal function and severity of proteinuria. However, ALS levels are altered in renal failure and nephrotic syndrome, which may be due to increased renal loss or diminished hepatic production or both.

Alterations of insulin-like growth factor binding protein 3 (IGFBP-3) glycosylation in patients with breast tumours

OBJECTIVES

Insulin-like growth factor binding protein-3 (IGFBP-3) is an important modulator of development and progression of breast cancer as it regulates the amount of free, physiologically active IGF-I and IGF-II. Changes in the glycosylation pattern within IGFBP-3 may affect its interaction with ligands. The aim of this study was to investigate whether such changes occur during disease progression.

DESIGN AND METHODS

IGFBP-3 in serum samples from healthy women and from women with breast tumours was characterised in terms of its concentration (IRMA), glycosylation moiety (lectin-affinity chromatography) and distribution of molecular species (immunoblotting).

RESULTS

In patients with benign tumours the concentration and carbohydrate content of IGFBP-3 was unaltered compared to healthy women. In patients with malignant tumours in most cases these two parameters were unchanged, but there were women whose concentration of IGFBP-3 was reduced and its structure was altered. In non-surviving cancer patients the concentration of IGFBP-3 was significantly reduced and these molecules contained a greater amount of biantennary complex type N-glycans having more mannose, fucose, bisecting GlcNAc and terminal sialic acid residues.

CONCLUSION

Our results showed that breast cancer progression causes alterations of IGFBP-3 glycosylation. The extent of changes increases with breast cancer severity.

Past recreational physical activity, body size, and all-cause mortality following breast cancer diagnosis: results from the Breast Cancer Family Registry

Few studies have considered the joint association of body mass index (BMI) and physical activity, two modifiable factors, with all-cause mortality after breast cancer diagnosis. Women diagnosed with invasive breast cancer (n = 4,153) between 1991 and 2000 were enrolled in the Breast Cancer Family Registry through population-based sampling in Northern California, USA; Ontario, Canada; and Melbourne and Sydney, Australia. During a median follow-up of 7.8 years, 725 deaths occurred. Baseline questionnaires assessed moderate and vigorous recreational physical activity and BMI prior to diagnosis. Associations with all-cause mortality were assessed using Cox proportional hazards regression, adjusting for established prognostic factors. Compared with no physical activity, any recreational activity during the 3 years prior to diagnosis was associated with a 34% lower risk of death [hazard ratio (HR) = 0.66, 95% confidence interval (CI): 0.51-0.85] for women with estrogen receptor (ER)-positive tumors, but not those with ER-negative tumors; this association did not appear to differ by race/ethnicity or BMI. Lifetime physical activity was not associated with all-cause mortality. BMI was positively associated with all-cause mortality for women diagnosed at age > or =50 years with ER-positive tumors (compared with normal-weight women, HR for overweight = 1.39, 95% CI: 0.90-2.15; HR for obese = 1.77, 95% CI: 1.11-2.82). BMI associations did not appear to differ by race/ethnicity. Our findings suggest that physical activity and BMI exert independent effects on overall mortality after breast cancer.

IGFBP2 and IGFBP3 protein expressions in human breast cancer: association with hormonal factors and obesity

PURPOSE

The insulin-like growth factor (IGF) signaling system is involved in breast cancer initiation and progression. The prognostic relevance of tumor expression patterns of IGFI-related proteins remains poorly understood. This study associates the expression of selected IGF proteins with breast tumor and patient characteristics.

EXPERIMENTAL DESIGN

IGFI, IGFI receptor, IGF-binding protein (IGFBP)2, and IGFBP3 expression was measured in 855 primary breast carcinomas by immunohistochemistry using tissue microarrays. We investigated the association of tumor and nodal stage, grade, hormone receptor status, HER2 gene amplification, menopausal status, body mass index, and survival with IGF protein expression.

RESULTS

In contrast to IGFI, the expression of IGFI receptor, IGFBP2, and IGFBP3 was associated with estrogen receptor status. In addition, IGFBP3 was positively correlated with body mass index and premenopausal status. Importantly, IGFBP2 was an independent and positive predictor of overall survival (hazard ratio, 0.48; 95% confidence interval, 0.24-0.95; P = 0.04). There was a weak suggestion for IGFBP2 and overweight to modify each other's effect on survival.

CONCLUSIONS

According to these results, which need confirmation in larger patient series, the prognostic relevance of IGFBP2 and IGFBP3 protein expressions in breast cancer may depend on the hormonal context and body weight.