Pretreatment Insulin Levels as a Prognostic Factor for Breast Cancer Progression

Comparative study of dexamethasone premedication regimens with docetaxel chemotherapy in early HER-2 positive breast cancer: A safety net hospital experience

INTRODUCTION

Docetaxel can cause fluid retention reactions (FRRs) and hypersensitivity reactions (HSRs). The manufacturer recommends a multi-day oral dexamethasone premedication to prevent these toxicities, but steroid related side effects and regimen compliance remain a concern. This study aimed to determine if modified dexamethasone premedication regimens resulted in differences in HSRs or FRRs to docetaxel. We also examined side effects of dexamethasone and delays in chemotherapy.

METHODS

A retrospective chart review was conducted on 82 early breast cancer patients treated with docetaxel. Three steroid regimens were examined: IV 20 mg single-dose dexamethasone, or IV 12 mg dexamethasone with either dexamethasone 8 mg BID for three days starting the day before chemotherapy or dexamethasone 4 mg BID for three days following chemotherapy. Adverse effects, delays in chemotherapy, and reasons for delays in chemotherapy were recorded.

RESULTS

The incidence and severity of FRRs and HSRs was low, with less than 10% incidence of HSRs or FRRs in any group. Delays were most common in the group receiving dexamethasone 8 mg BID for 3 days starting the day before chemotherapy (63.3%) (p < 0.05) and were most commonly due to patient noncompliance (26%).

CONCLUSION

A single dose of intravenous dexamethasone alone or followed by lower doses of oral dexamethasone may improve patient compliance and avoid delays in chemotherapy, without an increase in docetaxel toxicity.

Association of preoperative serum adipokines, insulin, and sex steroid hormones with breast cancer risk in the Indian women

BACKGROUND

Obesity-related factors such as adipokines, insulin, insulin-like growth factors, and sex steroid hormones have been reported to be involved in breast carcinogenesis. Studies across the world suggest an important, but still controversial, role of obesity in breast cancer risk. This study aims to evaluate the association of obesity-related factors such as adipokines, insulin, insulin resistance, and sex steroid hormones with breast cancer risk in the Indian population.

MATERIALS AND METHODS

Anthropometric and biochemical measurements were taken in 60 newly diagnosed and histologically confirmed breast cancer patients and 50 healthy controls. Preoperative serum levels of adiponectin, leptin, insulin, estrogen, and testosterone were measured using ELISA (enzyme-linked immunosorbent assay). The data were analyzed and compared.

RESULTS

The mean serum total cholesterol (T.CHOL) and leptin levels were significantly higher ( P = 0.047), whereas testosterone levels were significantly lower in patients than in controls. Waist circumference (WC) and leptin levels showed a significant positive association with breast cancer risk. Association of serum leptin levels with breast cancer risk persisted after adjusting for age, body mass index (BMI), and WC parameters (odds ratio [ OR ] = 1.042, P = 0.03). Leptin levels positively correlated with WC and triglycerides (TG), whereas insulin and insulin resistance positively correlated with BMI, WC, TG, and T.CHOL ( P < 0.05). Among the tumor characteristics, serum adiponectin showed a positive correlation with lymph node involvement, whereas serum estradiol levels were positively correlated with ER (estrogen receptor) and PR (progesterone receptor) status.

CONCLUSION

Together, our study supports the association of obesity (WC) with breast cancer risk and also suggests the potential role of leptin as a biomarker for breast cancer risk, independent of obesity.

Metabolic Profile and Negatively Association Between Insulin Resistance and Metastatic Incidence in Indonesian Primary Invasive Breast Cancer: A Cross-Sectional Study

Introduction

Metastatic breast cancer was associated with high morbidity and mortality. Insulin resistance was hypothesized to be related to the incidence of advanced breast cancer. Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) and Triglyceride/Glucose Index (TyG Index) are two metrics used to measure the degree of insulin resistance. This study aims to assess the relationship between the incidence of metastatic breast cancer and insulin resistance as reflected by both metrics.

Material and Methods

This study is a cross-sectional study involving 150 primary invasive breast cancer patients recruited from two hospitals of different sectors from August 2019 to April 2020. Patients with double cancer and autoimmune disorder were excluded from this study. Data obtained from the patients include age, body mass index (BMI), type 2 diabetes mellitus (T2DM) status and treatment, and low-density lipoprotein (LDL) cholesterol. The electronic medical records (EMR) was consulted to find histopathology examination result, cancer staging, and any missing data. The association between HOMA-IR and TyG with metastatic incidence was analyzed using either the Mann-Whitney test (for non-normally distributed data) or the independent-sample t-test (for normally distributed data).

Results

The mean of the TyG index is 8.60, and the median of HOMA-IR is 1.22. We found no significant correlation between both variables and the incidence of metastases.

Conclusion

Insulin resistance was not associated with metastatic breast cancer.

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.

Effect of Ketogenic Diets on Cardio-Metabolic Outcomes in Cancer Patients: A Systematic Review and Meta-Analysis of Controlled Clinical Trials

In this systematic review and meta-analysis of clinical controlled trials (CCTs) we aimed to investigate the efficacy of KDs as an adjuvant therapy on cardiometabolic outcomes in patient with cancer compared to conventional non-ketogenic diets. Only CCTs involving cancer patients that were assigned to either a KD or a standard diet control group were selected. Two reviewers independently extracted the data, and a meta-analysis was performed using a random effects model to estimate weighted mean differences (WMDs) and confidence intervals (CIs) in body composition, metabolite, lipid profile, liver and kidney function parameters and quality of life. This meta-analysis showed a significant reduction in body weight (WMD= -2.99 kg; 95% CI: -4.67, -1.31; and P < 0.001), BMI (WMD= -1.08 kg/m²; 95% CI: -1.81, -0.34; P ≤ 0.002) and fat mass (WMD= -1.48 kg; 95% CI: -2.56, -0.40; and P = 0.007) by a KD. KDs significantly decreased glucose (WMD= -5.22 mg/dl; 95% CI: -9.0, -1.44; and P = 0.007), IGF-1 (WMD= -17.52 ng/ml; 95% CI: -20.24, -14.8; and P ˂0.001) and triglyceride (WMD= -24.46 mg/dl; 95% CI: -43.96, -4.95; and P = 0.014) levels. Furthermore, KDs induced ketosis by increasing β-hydroxybutyrate (WMD= 0.56 mmol/l; 95% CI: 0.37, 0.75; and P < 0.001). There were non-significant pooled effects of KDs on improving insulin, C-reactive protein and cholesterol levels and kidney and liver function. Emotional functioning was even increased significantly in the KD compared to the SD groups. In summary we found that KDs result in a greater reduction in glucose, IGF-1, triglycerides, body weight, BMI, and fat mass in cancer patients compared to traditional non-ketogenic diets and improved emotional functioning. The quality of evidence in the meta-analysis was moderate according to the Nutrigrade assessment.

Intermittent fasting during adjuvant chemotherapy may promote differential stress resistance in breast cancer patients

Background

Preclinical studies prove that short-term fasting secures healthy cells against chemotherapy side effects and makes malignant cells more vulnerable to them. This study aimed to examine the effects of intermittent fasting (IF) during adjuvant chemotherapy AC (doxorubicin, cyclophosphamide) protocol in breast cancer (BC) patients.

Methods

Forty-eight newly diagnosed human epidermal growth factor receptor 2-negative (HER2 negative) BC patients were divided equally into two groups (24 each). The first group was recruited to fast intermittently for three consecutive days around chemotherapy for 18 h a day from 12 am to 6 pm and eats through 6 h a day from 6 pm to 12 am with permission of drinking water during fasting hours (IF group). This IF was repeated every 3 weeks for four cycles. The second group is a non-fasting (NF) group that was allowed to eat regularly. Toxicity in the two groups was compared. Hematologic, metabolic, and inflammatory parameters were measured and compared.

Results

Toxicity related to the gastrointestinal tract (GIT) was reduced in the IF group. Hematologic parameters showed no significant variations between the two studied groups after cycle 4. There was a significant increase in median glucose and median insulin levels (P < 0.001 and P = 0.001, respectively) in the NF group between baseline and after cycle 4. In addition, there was a significant decrease in the median insulin level (P = 0.002) in the IF group between the two time points.

Conclusion

IF throughout chemotherapy was well tolerated and decreased the toxicity of chemotherapy. Additionally, IF-improved metabolic profiles of patients may have a positive impact on the clinical efficacy of chemotherapy.

Associations of insulin resistance and inflammatory biomarkers with endometrial cancer survival: The Alberta endometrial cancer cohort study

Background

Metabolic dysfunction and inflammation have been associated with endometrial cancer risk; however, their influence on endometrial cancer survival is less understood.

Methods

A prospective cohort study of 540 endometrial cancer cases diagnosed between 2002 and 2006 in Alberta were followed for survival outcomes to 2019. Baseline blood samples collected either pre‐ or post‐hysterectomy were analyzed for glucose, insulin, adiponectin, leptin, tumor necrosis factor‐α, interleukin‐6, and C‐reactive protein. Covariates were obtained during in‐person interviews and via medical chart abstraction. Cox proportional hazard regression models were used to estimate multivariable‐adjusted hazard ratios (HR) and 95% confidence intervals (95% CI) for the association between each biomarker and disease‐free and overall survival.

Results

Blood samples were collected from 520 of the 540 participants (presurgical n = 235; postsurgical n = 285). During the median follow‐up of 14.3 years (range 0.4–16.5 years), there were 125 recurrences, progressions, and/or deaths with 106 overall deaths. None of the biomarkers were associated with disease‐free or overall survival in multivariable‐adjusted analyses. In an exploratory stratified analysis, the highest level of presurgical adiponectin, compared to the lowest level, was associated with improved disease‐free (HR = 0.42, 95% CI = 0.20–0.85) and overall (HR = 0.41, 95% CI = 0.18–0.92) survival, whereas no statistically significant associations were noted for postsurgical measures of adiponectin.

Conclusions

Overall, there was no evidence of an association between biomarkers of insulin resistance and inflammation with mortality outcomes in endometrial cancer survivors. Future cohort studies with serial blood samples are needed to understand the impact of changes in insulin resistance and inflammatory markers on endometrial cancer survival.

Comparative analysis of protein-protein interaction networks in metastatic breast cancer

Metastatic lesions leading causes of the majority of deaths in patients with the breast cancer. The present study aimed to provide a comprehensive analysis of the differentially expressed genes (DEGs) in the brain (MDA-MB-231 BrM2) and lung (MDA-MB-231 LM2) metastatic cell lines obtained from breast cancer patients compared with those who have primary breast cancer. We identified 981 and 662 DEGs for brain and lung metastasis, respectively. Protein-protein interaction (PPI) analysis revealed seven shared (PLCB1, FPR1, FPR2, CX3CL1, GABBR2, GPR37, and CXCR4) hub genes between brain and lung metastasis in breast cancer. Moreover, GNG2 and CXCL8, C3, and PTPN6 in the brain and SAA1 and CCR5 in lung metastasis were found as unique hub genes. Besides, five co-regulation of clusters via seven important co-expression genes (COL1A2, LUM, SPARC, THBS2, IL1B, CXCL8, THY1) were identified in the brain PPI network. Clusters screening followed by biological process (BP) function and pathway enrichment analysis for both metastatic cell lines showed that complement receptor signalling, acetylcholine receptor signalling, and gastric acid secretion pathways were common between these metastases, whereas other pathways were site-specific. According to our findings, there are a set of genes and functional pathways that mark and mediate breast cancer metastasis to the brain and lungs, which may enable us understand the molecular basis of breast cancer development in a deeper levele to the brain and lungs, which may help us gain a more complete understanding of the molecular underpinnings of breast cancer development.

Insulin resistance and the development of breast cancer in premenopausal women: the Kangbuk Samsung Health Study

PURPOSE

Research on the role of insulin resistance (IR) in breast cancer risk in premenopausal women is scarce. We aimed to investigate the relationship between IR and the development of breast cancer in premenopausal women.

METHODS

We analyzed the prospective association of IR and incident breast cancer in premenopausal women without breast cancer at baseline using a subsample of the Kangbuk Samsung Health Study.

RESULTS

Among 134,488 Korean premenopausal women, 696 women developed incident breast cancers during a median follow-up of 4.34 years. After adjustment for dense breast and other potential confounders, HR (95% CI) for incident breast cancer comparing HOMA-IR quintiles 2, 3, 4, and 5 to the first quintile was 0.91 (0.71-1.17), 0.89 (0.69-1.15), 0.75 (0.57-0.98), and 0.87 (0.65-1.16), respectively (P for trend = 0.117), while HR (95% CI) comparing insulin quintiles 2, 3, 4, and 5 to the first quintile was 1.02 (0.80-1.30), 0.90 (0.69-1.16), 0.72 (0.54-0.96), and 0.96 (0.72-1.28), respectively (P for trend = 0.151). This pattern did not significantly differ by obesity. These results were attenuated and no longer significant in time-dependent analyses where updated status of insulin and other covariates over time were treated as time-varying covariates.

CONCLUSION

Our findings do not support the positive relationship of IR with the development of breast cancer in premenopausal women, unlike in postmenopausal women. Thus, the role of IR as a risk factor for breast cancer may differ by menopausal status.

Types of carbohydrate intake and breast cancer survival

OBJECTIVE

To investigate the associations of different types of carbohydrate intake after breast cancer diagnosis with breast cancer-specific and all-cause mortality.

METHODS

We prospectively assessed post-diagnostic intake of total sugar, added sugar, and natural sugar as well as carbohydrate from different sources, among 8932 women with stage I-III breast cancer that were identified in the Nurses' Health Study from 1980 to 2010 and Nurses' Health Study II from 1991 to 2011. Participants completed a validated food frequency questionnaire every four years after diagnosis and were followed up for death.

RESULTS

We prospectively documented 1071 deaths due to breast cancer and 2532 all-cause deaths, over a mean of 11.5 years of follow-up. After adjustment for confounding variables, greater post-diagnostic total sugar intake was suggestively associated with greater risk of breast cancer-specific mortality [hazard ratio (HR)_Q5vsQ1 = 1.16, 95% confidence interval (CI ) = 0.95-1.41; P_trend = 0.02] and significantly associated with greater risk of all-cause mortality (HR_Q5vsQ1 = 1.23, 95% CI = 1.08-1.41; P_trend = 0.0001). Greater post-diagnostic added sugar intake was significantly associated with greater risk of all-cause mortality (HR_Q5vsQ1 = 1.20, 95% CI = 1.06-1.36; P_trend = 0.001). Post-diagnostic natural sugar (occurring in foods and not added as an ingredient) intake was not associated with mortality risk. Greater post-diagnostic fructose intake was significantly associated with greater risk of breast cancer-specific mortality (HR_Q5vsQ1 = 1.34, 95% CI = 1.10-1.64; P_trend = 0.005) and all-cause mortality (HR_Q5vsQ1 = 1.16, 95% CI = 1.02-1.32; P_trend = 0.01). High post-diagnostic intake of sucrose was associated with higher risk of breast cancer-specific and all-cause mortality. Increased post-diagnostic intake of carbohydrate from fruit juice was significantly associated with higher risk of breast cancer-specific and all-cause mortality and carbohydrate from vegetables was significantly associated with lower risk of all-cause mortality. High post-diagnostic intake of carbohydrate from potatoes was suggestively associated with higher risk of breast cancer-specific mortality and carbohydrate from refined grains was suggestively associated with higher risk of all-cause mortality.

CONCLUSIONS

We found that higher total sugar intake, especially added sugar, sucrose, and fructose, as well as carbohydrate from fruit juice after a breast cancer diagnosis were associated with poorer prognosis. High post-diagnostic intake of carbohydrate from vegetables was associated with reduced risk of mortality.

Dietary carbohydrate quality and risk of breast cancer among women

Background

A few studies have examined the relationship between carbohydrate quality index (CQI) and risk of breast cancer (BC) among women in Middle Eastern countries. We studied the associations between carbohydrate quality index and the risk of BC in overall and by menopausal status.

Methods

In this case-control study, dietary intake of 461 women with pathologically confirmed BC within the past year were examined. The same information were collected for 495 apparently healthy controls using a 168-item validated FFQ. Carbohydrate quality was determined by considering four criteria including: ratio of solid carbohydrates to total carbohydrates, dietary fiber intake, GI and the ratio of whole grains to total grains.

Results

Mean GI and GL of participants were totally 57.5 ± 7.2 and 245.7 ± 64.7, respectively. A trend toward significant association was seen between GI and odds of BC in the whole population; such that after stratifying analysis by menopausal status, premenopausal women in the highest quartile of GI were 1.85 times higher likely to have BC than those in the lowest quartile (95% CI: 1.12, 3.07, P = 0.01). We found that women with the greatest CQI had lower odds for BC, compared with those with the lowest CQI (0.63; 95% CI: 0.43–0.94, P = 0.03). This association was remained after stratifying analysis by menopausal status in premenopausal (0.55; 95% CI: 0.34–0.90, P = 0.04).

Conclusion

We found that GI was directly and CQI inversely associated with odds of BC. In order to determine the effects of dietary carbohydrate quality prospective cohort studies are needed.

Fasting and Exercise in Oncology: Potential Synergism of Combined Interventions

Nutrition and exercise interventions are strongly recommended for most cancer patients; however, much debate exists about the best prescription. Combining fasting with exercise is relatively untouched within the oncology setting. Separately, fasting has demonstrated reductions in chemotherapy-related side effects and improved treatment tolerability and effectiveness. Emerging evidence suggests fasting may have a protective effect on healthy cells allowing chemotherapy to exclusively target cancer cells. Exercise is commonly recommended and attenuates treatment- and cancer-related adverse changes to body composition, quality of life, and physical function. Given their independent benefits, in combination, fasting and exercise may induce synergistic effects and further improve cancer-related outcomes. In this narrative review, we provide a critical appraisal of the current evidence of fasting and exercise as independent interventions in the cancer population and discuss the potential benefits and mechanisms of combined fasting and exercise on cardiometabolic, body composition, patient-reported outcomes, and cancer-related outcomes. Our findings suggest that within the non-cancer population combined fasting and exercise is a viable strategy to improve health-related outcomes, however, its safety and efficacy in the oncology setting remain unknown. Therefore, we also provide a discussion on potential safety issues and considerations for future research in the growing cancer population.

Targeting obesity-related dysfunction in hormonally driven cancers

Obesity is a risk factor for at least 13 different types of cancer, many of which are hormonally driven, and is associated with increased cancer incidence and morbidity. Adult obesity rates are steadily increasing and a subsequent increase in cancer burden is anticipated. Obesity-related dysfunction can contribute to cancer pathogenesis and treatment resistance through various mechanisms, including those mediated by insulin, leptin, adipokine, and aromatase signalling pathways, particularly in women. Furthermore, adiposity-related changes can influence tumour vascularity and inflammation in the tumour microenvironment, which can support tumour development and growth. Trials investigating non-pharmacological approaches to target the mechanisms driving obesity-mediated cancer pathogenesis are emerging and are necessary to better appreciate the interplay between malignancy, adiposity, diet and exercise. Diet, exercise and bariatric surgery are potential strategies to reverse the cancer-promoting effects of obesity; trials of these interventions should be conducted in a scientifically rigorous manner with dose escalation and appropriate selection of tumour phenotypes and have cancer-related clinical and mechanistic endpoints. We are only beginning to understand the mechanisms by which obesity effects cell signalling and systemic factors that contribute to oncogenesis. As the rates of obesity and cancer increase, we must promote the development of non-pharmacological lifestyle trials for the treatment and prevention of malignancy.

Consumption of sugar-sweetened and artificially sweetened beverages and breast cancer survival

BACKGROUND

The activation of insulin pathways is hypothesized to promote tumor growth and worsen breast cancer survival. Sugar-sweetened beverages (SSBs) can lead to a higher risk of insulin resistance and may affect survival. The authors prospectively evaluated the relation of postdiagnostic SSB and artificially sweetened beverage (ASB) consumption with mortality among women with breast cancer.

METHODS

In total, 8863 women with stage I through III breast cancer were identified during follow-up of the Nurses' Health Study (NHS; 1980-2010) and Nurses' Health Study II (NHSII; 1991-2011). Women completed a validated food frequency questionnaire every 4 years after diagnosis and were followed until death or the end of follow-up (2014 for the NHS and 2015 for the NHSII). Multivariable Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of breast cancer-specific and all-cause mortality after adjusting for measures of adiposity and other potential predictors of cancer survival.

RESULTS

With a median follow-up of 11.5 years, 2482 deaths were prospectively documented, including 1050 deaths from breast cancer. Compared with women who had no consumption, women who had SSB consumption after diagnosis had higher breast cancer-specific mortality (>1 to 3 servings per week: HR, 1.31 [95% CI, 1.09-1.58]; >3 servings per week: HR, 1.35 [95% CI, 1.12-1.62]; P_trend = .001) and all-cause mortality (>1 to 3 servings per week: HR, 1.21 [95% CI, 1.07-1.37]; >3 servings per week: HR, 1.28 [95% CI, 1.13-1.45]; P_trend = .0001). In contrast, ASB consumption was not associated with higher breast cancer-specific or all-cause mortality. Furthermore, replacing 1 serving per day of SSB consumption with 1 serving per day of ASB consumption was not associated with a lower risk of mortality.

CONCLUSIONS

Higher postdiagnostic SSB consumption among breast cancer survivors was associated with higher breast cancer-specific mortality and death from all causes.

Diversity of insulin and IGF signaling in breast cancer: Implications for therapy

This review highlights the significance of the insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF-1R) signaling pathway in cancer and assesses its potential as a therapeutic target. Our emphasis is on breast cancer, but this pathway is central to the behavior of many cancers. An understanding of how IR/IGF-1R signaling contributes to the function of the normal mammary gland provides a foundation for understanding its aberrations in breast cancer. Specifically, dysregulation of the expression and function of ligands (insulin, IGF-1 and IGF-2), receptors and their downstream signaling effectors drive breast cancer initiation and progression, often in a subtype-dependent manner. Efforts to target this pathway for the treatment of cancer have been hindered by several factors including a lack of biomarkers to select patients that could respond to targeted therapy and adverse effects on normal metabolism. To this end, we discuss ongoing efforts aimed at overcoming such obstacles.

Time-restricted feeding normalizes hyperinsulinemia to inhibit breast cancer in obese postmenopausal mouse models

Accumulating evidence indicates that obesity with its associated metabolic dysregulation, including hyperinsulinemia and aberrant circadian rhythms, increases the risk for a variety of cancers including postmenopausal breast cancer. Caloric restriction can ameliorate the harmful metabolic effects of obesity and inhibit cancer progression but is difficult to implement and maintain outside of the clinic. In this study, we aim to test a time-restricted feeding (TRF) approach on mouse models of obesity-driven postmenopausal breast cancer. We show that TRF abrogates the obesity-enhanced mammary tumor growth in two orthotopic models in the absence of calorie restriction or weight loss. TRF also reduces breast cancer metastasis to the lung. Furthermore, TRF delays tumor initiation in a transgenic model of mammary tumorigenesis prior to the onset of obesity. Notably, TRF increases whole-body insulin sensitivity, reduces hyperinsulinemia, restores diurnal gene expression rhythms in the tumor, and attenuates tumor growth and insulin signaling. Importantly, inhibition of insulin secretion with diazoxide mimics TRF whereas artificial elevation of insulin through insulin pumps implantation reverses the effect of TRF, suggesting that TRF acts through modulating hyperinsulinemia. Our data suggest that TRF is likely to be effective in breast cancer prevention and therapy.

Predictive Factors Among Clinicopathological Characteristics for Sentinel Lymph Node Metastasis in T1-T2 Breast Cancer

Background

The axillary lymph node status is an important prognostic factor of breast cancer. This study explores the predictive factors for sentinel lymph node (SLN) metastasis among the preoperative clinicopathological features, including impaired glucose tolerance (IGT).

Methods

This study comprised patients diagnosed with breast cancer who underwent surgery at Nagasaki Harbor Medical Center between April 2014 and December 2019. The factors assessed using univariate and multivariate analyses were the clinicopathological data of these cancers, including the patient age, gender, menstrual status, breast or ovarian cancer family history, body mass index, glycosylated hemoglobin, clinical tumor size, nipple-tumor distance (NTD), tumor histology, histological grade, node status, estrogen receptor, progesterone receptor, human epidermal growth factor receptor type 2 status, and Ki67 labeling index.

Results

In the cohort of 313 cases, the ratio of SLN metastasis was 17.3%. A univariate analysis found that the tumor size, NTD, IGT, and clinical tumor stage were associated with SLN metastasis. In a multivariable analysis, the tumor size, NTD, and IGT were associated with SLN metastasis. The receiver operating characteristic curve showed a sensitivity and specificity of 61.1% and 65.6%, respectively, at a cut-off of 1.7 cm for the tumor size (area under the curve [AUC]: 0.664; 95% confidence interval: 0.592–0.736), and a sensitivity and specificity of 60.4% and 62.9%, respectively, at a cut-off of 2.0 cm for NTD (AUC: 0.651; 95% confidence interval: 0.571–0.731) to predict the risk of SLN metastasis.

Conclusion

T1 and T2 breast cancer patients with a larger tumor size, tumor located closer to the nipple, and IGT have a higher risk of SLN metastases than others.

Postdiagnostic Dietary Glycemic Index, Glycemic Load, Dietary Insulin Index, and Insulin Load and Breast Cancer Survival

BACKGROUND

We investigated the associations of postdiagnostic dietary glycemic index (GI), glycemic load (GL), insulin index (II), and insulin load (IL) with breast cancer-specific and all-cause mortality.

METHODS

Among 8,932 women with stage I-III breast cancer identified in the Nurses' Health Study (NHS; 1980-2010) and NHSII (1991-2011), we prospectively evaluated the associations between postdiagnostic GI, GL, II, and IL, and breast cancer-specific and all-cause mortality. Participants completed a validated food frequency questionnaire every 4 years after diagnosis.

RESULTS

During follow-up by 2014 in the NHS and 2015 in the NHSII, 2,523 deaths, including 1,071 from breast cancer, were documented. Higher postdiagnostic GL was associated with higher risk of both breast cancer-specific mortality [HR_Q5vsQ1 = 1.33; 95% confidence interval (CI) = 1.09-1.63; P _trend = 0.008] and all-cause mortality (HR_Q5vsQ1 = 1.26; 95% CI = 1.10-1.45; P _trend = 0.0006). Higher all-cause mortality was also observed with higher postdiagnostic GI (HR_Q5vsQ1 = 1.23; 95% CI = 1.08-1.40; P _trend = 0.001), II (HR_Q5vsQ1 = 1.20; 95% CI = 1.04-1.38; P _trend = 0.005), and IL (HR_Q5vsQ1 = 1.23; 95% CI = 1.07-1.42; P _trend = 0.0003). The associations were not modified by insulin receptor or estrogen receptor status of the tumor, or body mass index.

CONCLUSIONS

We found that higher dietary GL, reflecting postprandial glucose response, after a breast cancer diagnosis was associated with higher risk of breast cancer-specific mortality. Higher dietary GI, GL, II, and IL after a breast cancer diagnosis were associated with higher risk of death from any cause.

IMPACT

These results suggest that carbohydrate quantity and quality may be important in breast cancer prognosis.See related commentary by McTiernan, p. 252.

Is insulin resistance a predictor for complete response in breast cancer patients who underwent neoadjuvant treatment?

PURPOSE

Neoadjuvant chemotherapy is the standard front-line treatment modality in locally advanced breast cancer. Achieving pathological complete response (pCR) is a significant prognostic factor for prolonged disease-free and overall survival. Insulin resistance is defined as a pathological condition in which insulin effect is impaired in peripheral target tissues such as the skeletal muscle, liver, and adipose tissue. The relationship between breast cancer and insulin resistance is controversial. In this study, our aim is to evaluate the role of insulin resistance, body mass index (BMI), metabolic syndrome, and inflammation markers to predict complete response in breast cancer patients who underwent neoadjuvant treatment.

METHODS

Data from 55 locally advanced non-diabetic breast cancer patients, treated with neoadjuvant chemotherapy between 2015 and 2017, were retrospectively evaluated. Homeostatic model assessment, IR = insulin resistance (HOMA-IR) was calculated by using the obtained insulin and fasting blood glucose values before neoadjuvant chemotherapy (fasting insulin × fasting glucose/405). We considered a cut-off of 2.5 for insulin resistance. The systemic inflammatory index (SII), neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR) were calculated.

RESULTS

Twenty-five patients had no insulin resistance. The most common pathologic subtype (56%) was hormone receptor (HR) positive and human epidermal growth factor receptor-2 (Her-2)-negative invasive ductal carcinoma. Sixteen (29%) patients had a pathological complete response (pCR). We found that the probability of pCR in patients with insulin resistance was 4.7 times lower than that in patients without insulin resistance [OR: 4.7 (95%CI 1.7-17.2), p = 0.01].

CONCLUSION

Our results revealed that insulin resistance may have a negative effect on pathological complete response (pCR) following neoadjuvant therapy particularly with hormone-positive and Her-2-negative cases of non-diabetic breast cancer.

Impact of a ketogenic diet intervention during radiotherapy on body composition: III-final results of the KETOCOMP study for breast cancer patients

Background

Obesity and low muscle mass are associated with worse outcomes of breast cancer patients. We conducted a controlled trial to study the impact of a ketogenic diet (KD) based on natural foods versus an unspecified standard diet (SD) on body composition in breast cancer patients undergoing radiotherapy.

Methods

Patients with non-metastasized breast cancer were allocated to either the KD (N = 32) or the SD (N = 31) during radiotherapy. Body composition was measured weekly by bioimpedance analysis. Blood parameters and quality of life were assessed before, during, and at the end of radiotherapy.

Results

A total of 29 KD and 30 SD patients completed the study. During radiotherapy, mean and median fasting BHB concentrations in the KD group were 0.72 and 0.49 mmol/l (range 0.06–4.9) which was significantly higher than those in the SD group (p < 2.2 × 10⁻¹⁶). There was a very small and insignificant increase in body weight and fat mass in the SD group, as well as a decrease of fat free mass. In contrast, patients in the KD group lost body weight and fat free and skeletal muscle mass quickly after diet onset, which for the most part was related to water losses. The KD did not cause further substantial changes in fat free or skeletal muscle mass, but was associated with a gradual decrease of 0.4 kg body weight and fat mass per week (p < 0.0001). The KD significantly decreased free T3 levels by 0.06 pg/ml/week (p = 6.3 × 10⁻⁵). Global quality of life remained stable in the SD group but increased in the KD group from a score of 66.7 to 75.0 (p = 0.20).

Conclusions

In breast cancer patients undergoing curative radiotherapy, a KD based on natural foods is feasible. After initial water losses, the KD tends to reduce body weight and fat mass while preserving fat free and skeletal muscle mass.

Trial registration

ClinicalTrials.gov identifier: NCT02516501, registered on August 06, 2015.

Insulin resistance and breast cancer incidence and mortality in postmenopausal women in the Women's Health Initiative

BACKGROUND

Insulin resistance is associated with higher all-cause and cancer-specific mortality in postmenopausal women. However, to the authors' knowledge, information regarding insulin resistance and breast cancer mortality risk is limited. Therefore, the authors examined associations between insulin resistance and breast cancer incidence and mortality in a subsample of Women's Health Initiative participants.

METHODS

A total of 22,837 postmenopausal women with fasting baseline glucose and insulin levels were followed for incident breast cancer and breast cancer mortality. Breast cancers were verified by medical record review and serial National Death Index linkage-enhanced mortality findings. Insulin resistance was estimated using the homeostatic model assessment of insulin resistance (HOMA-IR). Multivariable Cox proportional hazards models were used to compute hazard ratios (HRs) with 95% confidence intervals (95% CIs) for quartile comparisons. Outcomes included breast cancer incidence, deaths from breast cancer, and deaths after breast cancer (breast cancer followed by death from any cause).

RESULTS

During a median of 19.8 years of follow-up of 1328 breast cancer cases, there were 512 deaths reported, 151 of which were from breast cancer. Breast cancer incidence was higher in women in the highest HOMA-IR quartile (HR, 1.34; 95% CI, 1.12-1.61 [P for trend = .003]). Although HOMA-IR was not found to be associated with risk of death from breast cancer (HR, 1.04; 95% CI, 0.60-1.79), women in the highest versus those in the lowest HOMA-IR quartile were at a higher risk of death after breast cancer (HR, 1.78; 95% CI, 1.32-2.39 [P for trend <.001]).

CONCLUSIONS

Higher levels of insulin resistance in postmenopausal women are associated with higher breast cancer incidence and higher all-cause mortality after breast cancer.

Leptin Signaling in Liver Tissue of a Transgenic Breast Cancer Mouse Model

Leptin, an adipocytokine, is secreted from various tissues including the liver. The roles of both leptin and leptin receptor (ObR) in numerous pathophysiological conditions including mammary tumor (MT) development have been reported. However, the roles of leptin signaling-related proteins in the liver have not been reported previously in MT development. The objective of this study was to examine the expression levels of leptin and ObR in liver tissue of a transgenic breast cancer mouse model to investigate whether the roles of leptin in MT development are systemic or local. MMTV-TGF-α transgenic female mice were fed ad-libitum from week 10 up to week 74. Protein expression levels of leptin and ObR were measured in liver tissues of 74-week-old MMTV-TGF-α mice with and without MT by western blot. Serum leptin and insulin levels were measured using a enzyme-linked immunosorbent assay. Protein expression levels of leptin and ObR were similar in mice with MT compared to the ones without MT. Serum leptin and insulin levels were also not significantly different between the two groups. These results indicate that the effects of leptin signaling in MT development might be important at a local tissue level, such as mammary fat pad, and not as important at a systemic level.

Energy Restriction and Colorectal Cancer: A Call for Additional Research

: Colorectal cancer has the second highest cancer-related mortality rate, with an estimated 881,000 deaths worldwide in 2018. The urgent need to reduce the incidence and mortality rate requires innovative strategies to improve prevention, early diagnosis, prognostic biomarkers, and treatment effectiveness. Caloric restriction (CR) is known as the most robust nutritional intervention that extends lifespan and delays the progression of age-related diseases, with remarkable results for cancer protection. Other forms of energy restriction, such as periodic fasting, intermittent fasting, or fasting-mimicking diets, with or without reduction of total calorie intake, recapitulate the effects of chronic CR and confer a wide range of beneficial effects towards health and survival, including anti-cancer properties. In this review, the known molecular, cellular, and organismal effects of energy restriction in oncology will be discussed. Energy-restriction-based strategies implemented in colorectal models and clinical trials will be also revised. While energy restriction constitutes a promising intervention for the prevention and treatment of several malignant neoplasms, further investigations are essential to dissect the interplay between fundamental aspects of energy intake, such as feeding patterns, fasting length, or diet composition, with all of them influencing health and disease or cancer effects. Currently, effectiveness, safety, and practicability of different forms of fasting to fight cancer, particularly colorectal cancer, should still be contemplated with caution.

Breast Tissue Biology Expands the Possibilities for Prevention of Age-Related Breast Cancers

Preventing breast cancer before it is able to form is an ideal way to stop breast cancer. However, there are limited existing options for prevention of breast cancer. Changes in the breast tissue resulting from the aging process contribute to breast cancer susceptibility and progression and may therefore provide promising targets for prevention. Here, we describe new potential targets, immortalization and inflammaging, that may be useful for prevention of age-related breast cancers. We also summarize existing studies of warfarin and metformin, current drugs used for non-cancerous diseases, that also may be repurposed for breast cancer prevention.

Addition of zoledronic acid to neoadjuvant chemotherapy is not beneficial in patients with HER2-negative stage II/III breast cancer: 5-year survival analysis of the NEOZOTAC trial (BOOG 2010-01)

BACKGROUND

Adjuvant bisphosphonates are associated with improved breast cancer survival in postmenopausal patients. Addition of zoledronic acid (ZA) to neoadjuvant chemotherapy did not improve pathological complete response in the phase III NEOZOTAC trial. Here we report the results of the secondary endpoints, disease-free survival, (DFS) and overall survival (OS).

PATIENTS AND METHODS

Patients with HER2-negative, stage II/III breast cancer were randomized to receive the standard 6 cycles of neoadjuvant TAC (docetaxel/doxorubicin/cyclophosphamide) chemotherapy with or without 4 mg intravenous (IV) ZA administered within 24 h of chemotherapy. This was repeated every 21 days for 6 cycles. Cox regression models were used to evaluate the effect of ZA and covariates on DFS and OS. Regression models were used to examine the association between insulin, glucose, insulin growth factor-1 (IGF-1) levels, and IGF-1 receptor (IGF-1R) expression with survival outcomes.

RESULTS

Two hundred forty-six women were eligible for inclusion. After a median follow-up of 6.4 years, OS for all patients was significantly worse for those who received ZA (HR 0.468, 95% CI 0.226-0.967, P = 0.040). DFS was not significantly different between the treatment arms (HR 0.656, 95% CI 0.371-1.160, P = 0.147). In a subgroup analysis of postmenopausal women, no significant difference in DFS or OS was found for those who received ZA compared with the control group (HR 0.464, 95% CI 0.176-1.222, P = 0.120; HR 0.539, 95% CI 0.228-1.273, P = 0.159, respectively). The subgroup analysis of premenopausal patients was not significantly different for DFS and OS ((HR 0.798, 95% CI 0.369-1.725, P = 0.565; HR 0.456, 95% CI 0.156-1.336, P = 0.152, respectively). Baseline IGF-1R expression was not significantly associated with DFS or OS. In a predefined additional study, lower serum levels of insulin were associated with improved DFS (HR 1.025, 95% CI 1.005-1.045, P = 0.014).

CONCLUSIONS

Our results suggest that ZA in combination with neoadjuvant chemotherapy was associated with a worse OS in breast cancer (both pre- and postmenopausal patients). However, in a subgroup analysis of postmenopausal patients, ZA treatment was not associated with DFS or OS. Also, DFS was not significantly different between both groups. IGF-1R expression in tumor tissue before and after neoadjuvant treatment did not predict survival.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01099436 , April 2010.

Influence of pathogenetic factors of type 2 diabetes on activation of PI3K/AkT/mTOR pathway and on the development of endometrial and breast cancer

Type 2 diabetes (T2D), which is an epidemic of the 20th century, increases mortality, caused not only by cardiovascular diseases but also cancer. Pathogenetic factors of T2D lead to dysfunction of intracellular regulatory systems, particularly of PI3K/Akt/mTOR signaling pathway, which is involved in development of breast and endometrial cancer. During the study, the activation of this pathway by cancer and T2D was examined by determining the content of phosphorylated PRAS40 and p70S6K1. We studied the link between these kinases and pathogenetic factors of T2D. 65 women were examined. Patients were divided into four groups: І – healthy, ІІ – women with T2D, ІІІ – women with cancer without diabetes, IV – women with cancer and T2D. Level of HbA1c was determined by the ion-exchange chromatography. Levels of insulin, IGF-1, phospho-PRAS40, phospho-p70S6K1 were determined in PBMCs by immune-enzymatic methods. According to research results, significant hyperinsulinemia was detected in both groups with T2D. The highest level of insulin was in group II. A significantly higher level of IGF-1 was found only in patients with cancer of group III. The content of phospho-PRAS40 and phospho-p70S6K1 was higher in women with T2D of group II and in women with cancer of group III. Patients in group IV with combination of cancer and T2D had a lower level of phospho-PRAS40 in comparison to other groups. Phospho-PRAS40 in group II correlates with insulin, IGF-1 and HbA1c; in groups III and IV only with BMI. Phospho-p70S6K1 correlates with IGF-1 and with HbA1c in group II. Pathogenetic factors of T2D activate the signal path PI3K/Akt/mTOR, which is involved in the regulation of oncogenesis and metabolism. Phosphorylation of PRAS40 and p70S6K1 reflects the activation of P13K/Akt/mTOR pathway in women with T2D. Increased levels the phospho-PRAS40 and phospho-p70S6K1 can be used as early markers of oncogenesis in women with T2D.

Effects of short-term fasting on cancer treatment

Growing preclinical evidence shows that short-term fasting (STF) protects from toxicity while enhancing the efficacy of a variety of chemotherapeutic agents in the treatment of various tumour types. STF reinforces stress resistance of healthy cells, while tumor cells become even more sensitive to toxins, perhaps through shortage of nutrients to satisfy their needs in the context of high proliferation rates and/or loss of flexibility to respond to extreme circumstances. In humans, STF may be a feasible approach to enhance the efficacy and tolerability of chemotherapy. Clinical research evaluating the potential of STF is in its infancy. This review focuses on the molecular background, current knowledge and clinical trials evaluating the effects of STF in cancer treatment. Preliminary data show that STF is safe, but challenging in cancer patients receiving chemotherapy. Ongoing clinical trials need to unravel if STF can also diminish toxicity and increase efficacy of chemotherapeutic regimes in daily practice.

Breast Cancer Prognosis Using a Machine Learning Approach

Machine learning (ML) has been recently introduced to develop prognostic classification models that can be used to predict outcomes in individual cancer patients. Here, we report the significance of an ML-based decision support system (DSS), combined with random optimization (RO), to extract prognostic information from routinely collected demographic, clinical and biochemical data of breast cancer (BC) patients. A DSS model was developed in a training set (n = 318), whose performance analysis in the testing set (n = 136) resulted in a C-index for progression-free survival of 0.84, with an accuracy of 86%. Furthermore, the model was capable of stratifying the testing set into two groups of patients with low- or high-risk of progression with a hazard ratio (HR) of 10.9 (p < 0.0001). Validation in multicenter prospective studies and appropriate management of privacy issues in relation to digital electronic health records (EHR) data are presently needed. Nonetheless, we may conclude that the implementation of ML algorithms and RO models into EHR data might help to achieve prognostic information, and has the potential to revolutionize the practice of personalized medicine.

Evaluation of Insulin-mediated Regulation of AKT Signaling in Childhood Acute Lymphoblastic Leukemia

OBJECTIVE

Hyperglycemia increases the risk of early recurrence and high mortality in some adult blood cancers. In response to increased glucose levels, insulin is secreted, and several studies have shown that insulin-induced AKT signaling can regulate tumor cell proliferation and apoptosis. The AKT pathway is aberrantly activated in adult acute lymphoblastic leukemia (ALL), but the mechanisms underlying this activation and its impact in pediatric patients with ALL are unclear.

MATERIALS AND METHODS

We evaluated the insulin-induced chemoresistance and AKT pathway activation by measuring cell proliferation, apoptosis, and other parameters in ALL cell lines (Jurkat and Reh cells), as well as in primary pediatric leukemic cell samples, after culture with insulin, the chemotherapeutic drugs daunorubicin (DNR), vincristine (VCR), and L-asparaginase (L-Asp), or anti-insulin-like growth factor-1 receptor (IGF-1R) monoclonal antibody.

RESULTS

DNR, VCR, and L-Asp-induced toxicity in Jurkat and Reh cells was reduced in the presence of insulin. DNR promoted cell proliferation, whereas DNR, VCR, and L-Asp all reduced apoptosis in both cell lines cotreated with insulin compared with that in cell lines treated with chemotherapeutics alone (P<0.05). Furthermore, addition of an anti-IGF-1R monoclonal antibody promoted apoptosis, downregulated IGF-1R expression, and decreased the phosphorylation of AKT, P70S6K, and mTOR intracellular signaling pathway proteins in both cell lines, as well as in primary cultures (P<0.05).

CONCLUSIONS

Our results suggest that insulin-induced chemoresistance and activation of the AKT signaling pathway in pediatric ALL cells.

Metabolite and lipoprotein responses and prediction of weight gain during breast cancer treatment

Background

Breast cancer treatment has metabolic side effects, potentially affecting risk of cardiovascular disease (CVD) and recurrence. We aimed to compare alterations in serum metabolites and lipoproteins during treatment between recipients and non-recipients of chemotherapy, and describe metabolite profiles associated with treatment-related weight gain.

Methods

This pilot study includes 60 stage I/II breast cancer patients who underwent surgery and were treated according to national guidelines. Serum sampled pre-surgery and after 6 and 12 months was analysed by MR spectroscopy and mass spectrometry. In all, 170 metabolites and 105 lipoprotein subfractions were quantified.

Results

The metabolite and lipoprotein profiles of chemotherapy recipients and non-recipients changed significantly 6 months after surgery (p < 0.001). Kynurenine, the lipid signal at 1.55–1.60 ppm, ADMA, 2 phosphatidylcholines (PC aa C38:3, PC ae C42:1), alpha-aminoadipic acid, hexoses and sphingolipids were increased in chemotherapy recipients after 6 months. VLDL and small dense LDL increased after 6 months, while HDL decreased, with triglyceride enrichment in HDL and LDL. At baseline, weight gainers had less acylcarnitines, phosphatidylcholines, lyso-phosphatidylcholines and sphingolipids, and showed an inflammatory lipid profile.

Conclusion

Chemotherapy recipients exhibit metabolic changes associated with inflammation, altered immune response and increased risk of CVD. Altered lipid metabolism may predispose for treatment-related weight gain.

Diazoxide for Lowering Insulin Levels in Breast Cancer Patients

Diazoxide is a nondiuretic benzothiadiazine that produces hyperglycemia by lowering insulin levels through activation of ATP‐sensitive K1‐channels and stimulating insulin degradation in the lysosomal system. Its effect on cancer growth is discussed.

Genetic Variants in Metabolic Signaling Pathways and Their Interaction with Lifestyle Factors on Breast Cancer Risk: A Random Survival Forest Analysis

Genetic variants in the insulin-like growth factor-I (IGF-I)/insulin resistance axis may interact with lifestyle factors, influencing postmenopausal breast cancer risk, but these interrelated pathways are not fully understood. In this study, we examined 54 single-nucleotide polymorphisms (SNP) in genes related to IGF-I/insulin phenotypes and signaling pathways and lifestyle factors in relation to postmenopausal breast cancer, using data from 6,567 postmenopausal women in the Women's Health Initiative Harmonized and Imputed Genome-Wide Association Studies. We used a machine-learning method, two-stage random survival forest analysis. We identified three genetic variants (AKT1 rs2494740, AKT1 rs2494744, and AKT1 rs2498789) and two lifestyle factors [body mass index (BMI) and dietary alcohol intake] as the top five most influential predictors for breast cancer risk. The combination of the three SNPs, BMI, and alcohol consumption (≥1 g/day) significantly increased the risk of breast cancer in a gene and lifestyle dose-dependent manner. Our findings provide insight into gene-lifestyle interactions and will enable researchers to focus on individuals with risk genotypes to promote intervention strategies. These data also suggest potential genetic targets in future intervention/clinical trials for cancer prevention in order to reduce the risk for breast cancer in postmenopausal women. Cancer Prev Res; 11(1); 44-51. ©2017 AACR.

Breast cancer is associated to impaired glucose/insulin homeostasis in premenopausal obese/overweight patients

The association between breast cancer (BCa) presence and altered glucose/insulin metabolism is controversial likely due to an inaccurate insulin resistance (IR) assessment and inappropriate stratification of patients by body-mass index (BMI) and menopausal state. 148 women with suspect of sporadic BCa were stratified by BMI and menopause. Fasting levels of glucose, insulin, glycohemoglobin and selected IR-related and tumor-derived markers were measured. Glucose/insulin levels during OGTT were used to calculate insulin resistance/sensitivity indexes. Analysis of 77 BCa-bearing patients and 71 controls showed an association between BCa and IR as demonstrated by impaired glucose/insulin homeostasis (increased fasting- and OGTT-induced glucose levels) and deteriorated IR indexes, which was especially patent in premenopausal women. The association between BCa presence and IR was markedly influenced by BMI, being obese BCa patients significantly more insulin resistant than controls. BCa presence was associated to elevated levels of IR (glucose, triglycerides) and tumor-derived (VEGF) markers, especially in overweight/obese patients. BCa presence is associated to IR in overweight/obese premenopausal but not in premenopausal normal weight or postmenopausal women. Our data support a bidirectional relationship between dysregulated/imbalanced glucose/insulin metabolism and BCa, as tumor- and IR-markers are correlated with the impairment of glucose/insulin metabolism in overweight/obese premenopausal BCa patients.

Racial differences in the effects of comorbidity on breast cancer-specific survival

PURPOSE

In an effort to explain racial disparities in breast cancer survival, this study aimed to investigate how comorbidity affects breast cancer-specific mortality by race.

METHODS

A retrospective cohort study was conducted using the Surveillance, Epidemiology and End Results-Medicare linked data including 68,090 women 66+ years, who were diagnosed with stage I-III breast cancer in the United States from 1994 to 2004. Hospital and outpatient claims from the year prior to breast cancer diagnosis were used to identify comorbid conditions and patients were followed for survival through 2010.

RESULTS

Competing risk survival analysis failed to demonstrate any negative comorbidity effects on breast cancer-specific survival for black women. An increased breast cancer-specific mortality hazard was observed for white women who had diabetes without complication relative to white women without this condition after adjusting for age and year of diagnosis (hazard ratio: 1.22, 95% confidence interval 1.13, 1.30). The Cochran-Armitage Test showed diabetes was associated with a later stage of diagnosis (p < 0.01) and a more aggressive tumor grade (p < 0.01) among white women in the study population.

CONCLUSION

Race specific comorbidity effects do not explain breast cancer-specific survival disparities. However, the relationship between diabetes and breast cancer, including the role of aggressive tumor characteristics, warrants special attention.

Changes in diet associated with cancer: An evolutionary perspective

Changes in diet are frequently correlated with the occurrence and progression of malignant tumors (i.e., cancer) in both humans and other animals, but an integrated conceptual framework to interpret these changes still needs to be developed. Our aim is to provide a new perspective on dietary changes in tumor‐bearing individuals by adapting concepts from parasitology. Dietary changes may occur alongside tumor progression for several reasons: (i) as a pathological side effect with no adaptive value, (ii) as the result of self‐medication by the host to eradicate the tumor and/or to slow down its progression, (iii) as a result of host manipulation by the tumor that benefits its progression, and finally (iv) as a host tolerance strategy, to alleviate and repair damages caused by tumor progression. Surprisingly, this tolerance strategy can be beneficial for the host even if diet changes are beneficial to tumor progression, provided that cancer‐induced death occurs sufficiently late (i.e., when natural selection is weak). We argue that more data and a unifying evolutionary framework, especially during the early stages of tumorigenesis, are needed to understand the links between changes in diet and tumor progression. We argue that a focus on dietary changes accompanying tumor progression can offer novel preventive and therapeutic strategies against cancer.

Interaction of insulin-like growth factor-I and insulin resistance-related genetic variants with lifestyle factors on postmenopausal breast cancer risk

PURPOSE

Genetic variants and traits in metabolic signaling pathways may interact with obesity, physical activity, and exogenous estrogen (E), influencing postmenopausal breast cancer risk, but these inter-related pathways are incompletely understood.

METHODS

We used 75 single-nucleotide polymorphisms (SNPs) in genes related to insulin-like growth factor-I (IGF-I)/insulin resistance (IR) traits and signaling pathways, and data from 1003 postmenopausal women in Women's Health Initiative Observation ancillary studies. Stratifying via obesity and lifestyle modifiers, we assessed the role of IGF-I/IR traits (fasting IGF-I, IGF-binding protein 3, insulin, glucose, and homeostatic model assessment-insulin resistance) in breast cancer risk as a mediator or influencing factor.

RESULTS

Seven SNPs in IGF-I and INS genes were associated with breast cancer risk. These associations differed between non-obese/active and obese/inactive women and between exogenous E non-users and users. The mediation effects of IGF-I/IR traits on the relationship between these SNPs and cancer differed between strata, but only roughly 35% of the cancer risk due to the SNPs was mediated by traits. Similarly, carriers of 20 SNPs in PIK3R1, AKT1/2, and MAPK1 genes (signaling pathways-genetic variants) had different associations with breast cancer between strata, and the proportion of the SNP-cancer relationship explained by traits varied 45-50% between the strata.

CONCLUSIONS

Our findings suggest that IGF-I/IR genetic variants interact with obesity and lifestyle factors, altering cancer risk partially through pathways other than IGF-I/IR traits. Unraveling gene-phenotype-lifestyle interactions will provide data on potential genetic targets in clinical trials for cancer prevention and intervention strategies to reduce breast cancer risk.

Targeting Insulin Receptor in Breast Cancer Using Small Engineered Protein Scaffolds

Insulin receptor (InsR) and the type I insulin-like growth factor (IGF1R) are homologous receptors necessary for signal transduction by their cognate ligands insulin, IGF-I and IGF-II. IGF1R mAbs, intended to inhibit malignant phenotypic signaling, failed to show benefit in patients with endocrine-resistant tumors in phase III clinical trials. Our previous work showed that in tamoxifen-resistant cells, IGF1R expression was lacking, but InsR inhibition effectively blocked growth. In endocrine-sensitive breast cancer cells, insulin was not growth stimulatory, likely due to the presence of hybrid InsR/IGF1R, which has high affinity for IGF-I, but not insulin. Combination inhibition of InsR and IGF1R showed complete suppression of the system in endocrine-sensitive breast cancer cells. To develop InsR-binding agents, we employed a small protein scaffold, T7 phage gene 2 protein (Gp2) with the long-term goal of creating effective InsR inhibitors and diagnostics. Using yeast display and directed evolution, we identified three Gp2 variants (Gp2 #1, #5, and #10) with low nanomolar affinity and specific binding to cell surface InsR. These Gp2 variants inhibited insulin-mediated monolayer proliferation in both endocrine-sensitive and resistant breast cancer, but did not downregulate InsR expression. Gp2 #5 and Gp2 #10 disrupted InsR function by inhibiting ligand-induced receptor activation. In contrast, Gp2 #1 did not block InsR phosphorylation. Notably, Gp2 #1 binding was enhanced by pretreatment of cells with insulin, suggesting a unique receptor-ligand-binding mode. These Gp2 variants are the first nonimmunoglobulin protein scaffolds to target insulin receptor and present compelling opportunity for modulation of InsR signaling. Mol Cancer Ther; 16(7); 1324-34. ©2017 AACR.

Effects of Exercise on Insulin, IGF Axis, Adipocytokines, and Inflammatory Markers in Breast Cancer Survivors: A Systematic Review and Meta-analysis

Background: Insulin, IGF axis, adiponectin, and inflammatory markers are associated with breast cancer. Given that physical activity improves prognosis of breast cancer survivors, we investigated the effects of exercise on these markers as potential mediators between physical activity and breast cancer.Methods: PubMed, EMBASE, CENTRAL, CINAHL, and SportDiscus were searched up to December 3, 2015, to identify randomized controlled trials (RCT) that investigated the effect of exercise on insulin, IGF axis, and cytokines in breast cancer survivors. Weighted mean difference (WMD) was calculated using either fixed- or random-effects models on the basis of the heterogeneity of the studies.Results: A total of 18 studies involving 681 breast cancer survivors were included, and these numbers were reduced for individual biomarker analyses. We found that exercise significantly reduced fasting insulin levels [WMD, -3.46 μU/mL; 95% confidence interval (CI), -5.97 to -0.95; P = 0.007]. Furthermore, potentially meaningful but statistically nonsignificant changes were observed in insulin resistance (WMD, -0.73; 95% CI, -0.54 to 0.13; P = 0.23), adiponectin (WMD, 1.17 μg/mL; 95% CI, -0.87 to 3.20; P = 0.26), and C-reactive protein (WMD, -1.10 mg/L; 95% CI, -2.39 to 0.20; P = 0.10). Subgroup analyses showed that fasting insulin levels were significantly more impacted in studies in which intervention participants experienced a weight reduction (WMD, -7.10 μU/mL; 95% CI, -10.31 to -3.90; P < 0.001).Conclusions: Exercise reduces fasting insulin levels in breast cancer survivors. This may be due to exercise-induced reductions in body weight.Impact: Practitioners and clinicians may better help breast cancer prognosis be improved through exercise, anticipating physiological effects on cancer. Cancer Epidemiol Biomarkers Prev; 26(3); 355-65. ©2016 AACR.

Prognostic value of glycated hemoglobin in colorectal cancer

AIM

To investigate the clinical significance of routinely used glycemic parameters in a cohort of colorectal cancer (CRC) patients.

METHODS

Pre-treatment fasting blood glucose, insulin, HbA_1c and homeostasis model of risk assessment (HOMA-IR) were retrospectively evaluated in a case-control study of 224 CRC and 112 control subjects matched for sex, obesity and diabetes frequency and blood lipid profile. Furthermore, the prognostic value of routinely used glycemic parameters towards progression-free (PFS) and overall survival (OS) was prospectively evaluated.

RESULTS

Fasting blood glucose, insulin, HOMA-IR and HbA_1c (all P < 0.0001) levels were higher in non-diabetic CRC patients compared with obesity-matched controls. All parameters were associated with increased CRC risk at ROC analysis, but no relationship with clinical-pathological variables or survival outcomes was observed for glycemia, insulinemia or HOMA-IR. Conversely, advanced CRC stage (P = 0.018) was an independent predictor of increased HbA_1c levels, which were also higher in patients who had disease progression compared with those who did not (P = 0.05). Elevated HbA_1c levels showed a negative prognostic value both in terms of PFS (HR = 1.24) and OS (HR = 1.36) after adjustment for major confounders, which was further confirmed in a subgroup analysis performed after exclusion of diabetic patients.

CONCLUSION

HbA_1c might have a negative prognostic value in CRC, thus suggesting that glycemic metabolic markers should be carefully monitored in these patients, independently of overt diabetes.