Role of inflammation and oxidative stress in post-menopausal oestrogen-dependent breast cancer

The Role of Adipokines in Tumor Progression and Its Association with Obesity

Obesity is a well-established risk factor for various malignancies and emerging evidence suggests that adipokines play a pivotal role in linking excess adiposity to tumorigenesis. Adipokines are bioactive molecules secreted by adipose tissue and their altered expression in obesity contributes to a pro-inflammatory, pro-angiogenic, and growth-promoting microenvironment conducive to tumorigenesis. Leptin, a key adipokine, activates survival and proliferative signaling pathways whereas adiponectin exhibits tumor-suppressive effects by inducing apoptosis and cell cycle arrest. Visfatin has also been documented to promote tumor growth, angiogenesis, migration, and invasion. Moreover, emerging studies suggest that adipokines, such as resistin, apelin, and chemerin, which are overexpressed in obesity, may also possess oncogenic functions. Despite advancements in our understanding of the roles of individual adipokines in cancer, the intricate interplay and crosstalk between adipokines, tumor cells, and the tumor microenvironment remain complex and multifaceted. This review highlights the evolving knowledge of how adipokines contribute to obesity-related tumorigenesis, shedding light on the potential of targeting adipokine signaling pathways as a novel therapeutic approach for obesity-associated cancers. Further research on the specific mechanisms and interactions between adipokines and tumor cells is crucial for a comprehensive understanding of obesity-associated cancer pathogenesis.

Obesity-Associated Breast Cancer: Analysis of Risk Factors and Current Clinical Evaluation

Several studies show that a significantly stronger association is obvious between increased body mass index (BMI) and higher breast cancer incidence. Additionally, obese and postmenopausal women are at higher risk of all-cause and breast cancer-specific mortality compared with non-obese women with breast cancer. In this context, increased levels of estrogens, excessive aromatization activity of the adipose tissue, overexpression of pro-inflammatory cytokines, insulin resistance, adipocyte-derived adipokines, hypercholesterolemia, and excessive oxidative stress contribute to the development of breast cancer in obese women. Genetic evaluation is an integral part of diagnosis and treatment for patients with breast cancer. Despite trimodality therapy, the four-year cumulative incidence of regional recurrence is significantly higher. Axillary lymph nodes as well as primary lesions have diagnostic, prognostic, and therapeutic significance for the management of breast cancer. In clinical setting, because of the obese population primary lesions and enlarged lymph nodes could be less palpable, the diagnosis may be challenging due to misinterpretation of physical findings. Thereby, a nomogram has been created as the "Breast Imaging Reporting and Data System" (BI-RADS) to increase agreement and decision-making consistency between mammography and ultrasonography (USG) experts. Additionally, the "breast density classification system," "artificial intelligence risk scores," ligand-targeted receptor probes," "digital breast tomosynthesis," "diffusion-weighted imaging," "18F-fluoro-2-deoxy-D-glucose positron emission tomography," and "dynamic contrast-enhanced magnetic resonance imaging (MRI)" are important techniques for the earlier detection of breast cancers and to reduce false-positive results. A high concordance between estrogen receptor (ER) and progesterone receptor (PR) status evaluated in preoperative percutaneous core needle biopsy and surgical specimens is demonstrated. Breast cancer surgery has become increasingly conservative; however, mastectomy may be combined with any axillary procedures, such as sentinel lymph node biopsy (SLNB) and/or axillary lymph node dissection whenever is required. As a rule, SLNB-guided axillary dissection in breast cancer patients who have clinically axillary lymph node-positive to node-negative conversion following neoadjuvant chemotherapy is recommended, because lymphedema is the most debilitating complication after any axillary surgery. There is no clear consensus on the optimal treatment of occult breast cancer, which is much discussed today. Similarly, the current trend in metastatic breast cancer is that the main palliative treatment option is systemic therapy.

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.

Excess body weight significantly affects systemic and tumor inflammatory status and correlates to poor prognosis parameters in patients with breast cancer

Introduction

Obesity is a pro-inflammatory disease critical for developing breast cancer (BC), which impacts the profiles of systemic inflammatory mediators and determinants of different disease clinical outcomes remains little explored.

Methods

A total of 195 patients diagnosed with breast cancer were included. Aiming to exclude chemotherapy interference on circulating mediators, samples were collected at diagnosis, out of the treatment period. Patients were classified as normal weight (BMI up to 24.9 kg/m2) or overweight (BMI ≥25.0 kg/m2). Serum levels of IL-4, IL-12, hydroperoxides, and nitric oxide metabolites (NOx) were measured. Also, tumor expression of inducible nitric oxide synthase (iNOS), TGF-β1, CD4⁺, and CD8⁺ lymphocytes were evaluated.

Results

IL-4 levels were significantly increased in the overweight BC group (p = 0.0329), including patients with luminal B subtype (p = 0.0443), presence of lymph node metastases (p = 0.0115) and age of diagnosis below 50 years, (p = 0.0488). IL-12 levels were significantly increased in overweight BC patients with lymph node metastases (p = 0.0115). Hydroperoxides were increased in overweight BC patients (p = 0.0437), including those with tumors smaller than 2 cm (p = 0.05). NOx levels were also increased in overweight BC patients, including those with luminal B disorders (p = 0.0443), high-grade tumors (p = 0.0351) and lymph node metastases (p = 0.0155). The expression of iNOS (p < 0.001) and TCD4+ lymphocytes (p = 0.0378) was significantly investigated in tumor biopsies from overweight BC women.

Conclusions

These data provide a picture of the influence of excess body weight on inflammatory mediators' systemic and tumoral profiles, especially in patients displaying poor outcome BC.

Obesity Is Associated with Immunometabolic Changes in Adipose Tissue That May Drive Treatment Resistance in Breast Cancer: Immune-Metabolic Reprogramming and Novel Therapeutic Strategies

White adipose tissue (WAT) represents an endocrinologically and immunologically active tissue whose primary role is energy storage and homeostasis. Breast WAT is involved in the secretion of hormones and proinflammatory molecules that are associated with breast cancer development and progression. The role of adiposity and systemic inflammation in immune responses and resistance to anti-cancer treatment in breast cancer (BC) patients is still not clear. Metformin has demonstrated antitumorigenic properties both in pre-clinical and clinical studies. Nevertheless, its immunomodulating properties in BC are largely unknown. This review aims to evaluate the emerging evidence on the crosstalk between adiposity and the immune-tumour microenvironment in BC, its progression and treatment resistance, and the immunometabolic role of metformin in BC. Adiposity, and by extension subclinical inflammation, are associated with metabolic dysfunction and changes in the immune-tumour microenvironment in BC. In oestrogen receptor positive (ER+) breast tumours, it is proposed that these changes are mediated via a paracrine interaction between macrophages and preadipocytes, leading to elevated aromatase expression and secretion of pro-inflammatory cytokines and adipokines in the breast tissue in patients who are obese or overweight. In HER2+ breast tumours, WAT inflammation has been shown to be associated with resistance to trastuzumab mediated via MAPK or PI3K pathways. Furthermore, adipose tissue in patients with obesity is associated with upregulation of immune checkpoints on T-cells that is partially mediated via immunomodulatory effects of leptin and has been paradoxically associated with improved responses to immunotherapy in several cancers. Metformin may play a role in the metabolic reprogramming of tumour-infiltrating immune cells that are dysregulated by systemic inflammation. In conclusion, evidence suggests that body composition and metabolic status are associated with patient outcomes. To optimise patient stratification and personalisation of treatment, prospective studies are required to evaluate the role of body composition and metabolic parameters in metabolic immune reprogramming with and without immunotherapy in patients with BC.

Regulatory Components of Oxidative Stress and Inflammation and Their Complex Interplay in Carcinogenesis

Cancer progression is closely linked to oxidative stress (OS) inflammation. OS is caused by an imbalance between the amount of reactive oxygen species produced and antioxidants present in the body. Excess ROS either oxidizes biomolecules or activates the signaling cascade, resulting in inflammation. Immune cells secrete cytokines and chemokines when inflammation is activated. These signaling molecules attract a wide range of immune cells to the site of infection or oxidative stress. Similarly, increased ROS production by immune cells at the inflamed site causes oxidative stress in the affected area. A review on the role of oxidative stress and inflammation in cancer-related literature was conducted to obtain data. All of the information gathered was focused on the current state of oxidative stress and inflammation in various cancers. After gathering all relevant information, a narrative review was created to provide a detailed note on oxidative stress and inflammation in cancer. Proliferation, differentiation, angiogenesis, migration, invasion, metabolic changes, and evasion of programmed cell death are all aided by OS and inflammation in cancer. Imbalance between reactive oxygen species (ROS) and antioxidants lead to oxidative stress that damages macromolecules (nucleic acids, lipids and proteins). It causes breakdown of the biological signaling cascade. Prolonged oxidative stress causes inflammation by activating transcription factors (NF-κB, p53, HIF-1α, PPAR-γ, Nrf2, AP-1) that alter the expression of many other genes and proteins, including growth factors, tumor-suppressor genes, oncogenes, and pro-inflammatory cytokines, resulting in cancer cell survival. The present review article examines the complex relationship between OS and inflammation in certain types of cancer (colorectal, breast, lung, bladder, and gastric cancer).

The relationship between Mediterranean-DASH diet intervention for the neurodegenerative delay (MIND) Diet and risk of breast Cancer: a case-control study among iranian adult women

BACKGROUND

choosing a healthier lifestyle and modifying dietary habits could prevent four million new people from developing cancer. Recently, a new index called the Mediterranean-dietary approach to stop hypertension (DASH) diet intervention for the neurodegenerative delay (MIND) diet has been developed. In the current study, we aimed to assess the relationship between the MIND diet and the risk of breast cancer (BC) among Tehranian adult women.

METHOD

In this hospital-based, case-control study, 134 Tehranian women ≥ 30 years old with recently (< 6 months) diagnosed BC, confirmed histologically and 272 women of the same age as control were included. Dietary intakes were assessed in a personal interview using a valid and reliable semi-quantitative 168-item food frequency questionnaire. The odds ratio (OR) and 95% confidence intervals (CI) of breast cancer across tertiles of the MIND diet were determined using multivariable-adjusted logistic regression analysis.

RESULTS

In the crude model, participants in the highest tertiles had lower odds of BC [(OR = 0.57; 95% CI,0.34-0.95), P for trend = 0.020)] than those with the lowest scores on the MIND diet. After controlling for potential confounding variables, individuals in the highest tertile of the MIND diet had a 45% lower risk of BC [(OR = 0.55; 95% CI, 0.32-0.96), P for trend = 0.021)] compared with those in the lowest tertile. Also, in women with an abortion history, higher adherence to the MIND diet was associated with a lower risk of BC [(OR = 0.15; 95% CI, 0.04-0.52, P for trend = 0.002)].

CONCLUSION

Our findings revealed that higher adherence to the MIND diet was associated with decreased BC risk, which was strongly observed among women with a history of abortion.

Proteomic Profiling of Extracellular Vesicles Released by Leptin-Treated Breast Cancer Cells: A Potential Role in Cancer Metabolism

Tumor extracellular vesicles (EVs), as endocytic vesicles able to transport nucleic acids, proteins, and metabolites in recipient cells, have been recognized fundamental mediators of cell-to-cell communication in breast cancer. The biogenesis and release of EVs are highly regulated processes and both the quantity of EVs and their molecular cargo might reflect the metabolic state of the producing cells. We recently demonstrated that the adipokine leptin, whose circulating levels correlate with adipose tissue expansion, is an inducer of EV release from breast cancer cells. Here, we show a specific proteomic signature of EVs released by MCF-7 breast cancer cells grown in the presence of leptin (Lep-EVs), in attempt to find additional molecular effectors linking obesity to breast cancer biology. An analysis of the proteomic profile of Lep-EVs by LC-MS/MS revealed a significant enrichment in biological processes, molecular functions, and cellular components mainly related to mitochondrial machineries and activity, compared to protein content of EVs from untreated breast cancer cells. Metabolic investigations, carried out to assess the autocrine effects of these vesicles on breast cancer cells, revealed that Lep-EVs were able to increase ATP levels in breast cancer cells. This result is associated with increased mitochondrial respiration evaluated by Seahorse analyzer, supporting the concept that Lep-EVs can modulate MCF-7 breast cancer cell oxidative metabolism. Moreover, taking into account the relevance of tumor immune cell crosstalk in the tumor microenvironment (TME), we analyzed the impact of these vesicles on macrophage polarization, the most abundant immune component in the breast TME. We found that tumor-derived Lep-EVs sustain the polarization of M0 macrophages, derived from the human THP-1 monocytic cells, into M2-like tumor-associated macrophages, in terms of metabolic features, phagocytic activity, and increased expression of CD206-positive population. Overall, our results indicate that leptin by inducing the release of EV-enriched in mitochondrial proteins may control the metabolism of MCF-7 breast cancer cells as well as that of macrophages. Characterization of tumor-derived EV protein cargo in an obesity-associated milieu, such as in the presence of elevated leptin levels, might allow identifying unique features and specific metabolic mechanisms useful to develop novel therapeutic approaches for treatment of breast cancer, especially in obese patients.

Reprogramming of Fatty Acid Metabolism in Gynaecological Cancers: Is There a Role for Oestradiol?

Gynaecological cancers are among the leading causes of cancer-related death among women worldwide. Cancer cells undergo metabolic reprogramming to sustain the production of energy and macromolecules required for cell growth, division and survival. Emerging evidence has provided significant insights into the integral role of fatty acids on tumourigenesis, but the metabolic role of high endogenous oestrogen levels and increased gynaecological cancer risks, notably in obesity, is less understood. This is becoming a renewed research interest, given the recently established association between obesity and incidence of many gynaecological cancers, including breast, ovarian, cervical and endometrial cancers. This review article, hence, comprehensively discusses how FA metabolism is altered in these gynaecological cancers, highlighting the emerging role of oestradiol on the actions of key regulatory enzymes of lipid metabolism, either directly through its classical ER pathways, or indirectly via the IGIFR pathway. Given the dramatic rise in obesity and parallel increase in the prevalence of gynaecological cancers among premenopausal women, further clarifications of the complex mechanisms underpinning gynaecological cancers are needed to inform future prevention efforts. Hence, in our review, we also highlight opportunities where metabolic dependencies can be exploited as viable therapeutic targets for these hormone-responsive cancers.

Antioxidative and Anti-Inflammatory Activities of Chrysin and Naringenin in a Drug-Induced Bone Loss Model in Rats

Oxidative stress (OS) mediators, together with the inflammatory processes, are considered as threatening factors for bone health. The aim of this study was to investigate effects of flavonoids naringenin and chrysin on OS, inflammation, and bone degradation in retinoic acid (13cRA)-induced secondary osteoporosis (OP) in rats. We analysed changes in body and uterine weight, biochemical bone parameters (bone mineral density (BMD), bone mineral content (BMC), markers of bone turnover), bone geometry parameters, bone histology, OS parameters, biochemical and haematological parameters, and levels of inflammatory cytokines. Osteoporotic rats had reduced bone Ca and P levels, BMD, BMC, and expression of markers of bone turnover, and increased values of serum enzymes alkaline phosphatase (ALP) and lactate dehydrogenase (LDH). Malondialdehyde (MDA) production in liver, kidney, and ovary was increased, while the glutathione (GSH) content and activities of antioxidant enzymes were reduced and accompanied with the enhanced release of inflammatory mediators TNF-α, IL-1β, IL-6, and RANTES chemokine (regulated on activation normal T cell expressed and secreted) in serum. Treatment with chrysin or naringenin improved bone quality, reduced bone resorption, and bone mineral deposition, although with a lower efficacy compared with alendronate. However, flavonoids exhibited more pronounced antioxidative, anti-inflammatory and phytoestrogenic activities, indicating their great potential in attenuating bone loss and prevention of OP.

Correlation of Leptin, Proinflammatory Cytokines and Oxidative Stress with Tumor Size and Disease Stage of Endometrioid (Type I) Endometrial Cancer and Review of the Underlying Mechanisms

Endometrioid endometrial cancer is associated with increased BMI and obesity through multiple pathogenetic mechanisms involving hyperestrogenism, hyperinsulinemia, altered adipokine secretion, inflammation, and oxidative stress. In the present study, we aimed to investigate the correlation between BMI, leptin, the proinflammatory cytokines IL-6 and TNFα, reactive oxygen species (ROS), and the traditional prognostic factors T, G, N and M status among type I endometrioid and type II endometrial cancer patients. We enrolled 305 consecutive endometrial cancer patients prospectively. We found that BMI, leptin, and IL-6 significantly correlated with T status, N status, and M status among endometrioid type I endometrial cancer patients. Among type II endometrial cancer patients, BMI and leptin did not correlate with any of the prognostic parameters, whereas there was a positive correlation between IL-6 and the presence of distant metastases. In the multivariate regression analysis, BMI, leptin, and IL-6 were independent predictive variables of T, N, and M status in endometrioid type I endometrial cancer patients. Our study demonstrates that weight gain, adiposity-related adipokines, inflammation, and oxidative stress correlate with the prognostic factors of endometrioid endometrial cancer. Knowledge of the role of obesity-related biological pathways and mediators in the pathogenesis and prognosis of endometrioid endometrial malignancies may offer new perspectives on combined therapeutic strategies that have not been explored to date, both in the advanced disease and in the adjuvant setting.

Natural and Synthetic Estrogens in Chronic Inflammation and Breast Cancer

The oncogenic role of estrogen receptor (ER) signaling in breast cancer has long been established. Interaction of estrogen with estrogen receptor (ER) in the nucleus activates genomic pathways of estrogen signaling. In contrast, estrogen interaction with the cell membrane-bound G-protein-coupled estrogen receptor (GPER) activates the rapid receptor-mediated signaling transduction cascades. Aberrant estrogen signaling enhances mammary epithelial cell proliferation, survival, and angiogenesis, hence is an important step towards breast cancer initiation and progression. Meanwhile, a growing number of studies also provide evidence for estrogen's pro- or anti-inflammatory roles. As other articles in this issue cover classic ER and GPER signaling mediated by estrogen, this review will discuss the crucial mechanisms by which estrogen signaling influences chronic inflammation and how that is involved in breast cancer. Xenoestrogens acquired from plant diet or exposure to industrial products constantly interact with and alter innate estrogen signaling at various levels. As such, they can modulate chronic inflammation and breast cancer development. Natural xenoestrogens generally have anti-inflammatory properties, which is consistent with their chemoprotective role in breast cancer. In contrast, synthetic xenoestrogens are proinflammatory and carcinogenic compounds that can increase the risk of breast cancer. This article also highlights important xenoestrogens with a particular focus on their role in inflammation and breast cancer. Improved understanding of the complex relationship between estrogens, inflammation, and breast cancer will guide clinical research on agents that could advance breast cancer prevention and therapy.

Emerging role of ferroptosis in breast cancer: New dawn for overcoming tumor progression

Breast cancer has become a serious threat to women's health. Cancer progression is mainly derived from resistance to apoptosis induced by procedures or therapies. Therefore, new drugs or models that can overcome apoptosis resistance should be identified. Ferroptosis is a recently identified mode of cell death characterized by excess reactive oxygen species-induced lipid peroxidation. Since ferroptosis is distinct from apoptosis, necrosis and autophagy, its induction successfully eliminates cancer cells that are resistant to other modes of cell death. Therefore, ferroptosis may become a new direction around which to design breast cancer treatment. Unfortunately, the complete appearance of ferroptosis in breast cancer has not yet been fully elucidated. Furthermore, whether ferroptosis inducers can be used in combination with traditional anti- breast cancer drugs is still unknown. Moreover, a summary of ferroptosis in breast cancer progression and therapy is currently not available. In this review, we discuss the roles of ferroptosis-associated modulators glutathione, glutathione peroxidase 4, iron, nuclear factor erythroid-2 related factor-2, superoxide dismutases, lipoxygenase and coenzyme Q in breast cancer. Furthermore, we provide evidence that traditional drugs against breast cancer induce ferroptosis, and that ferroptosis inducers eliminate breast cancer cells. Finally, we put forward prospect of using ferroptosis inducers in breast cancer therapy, and predict possible obstacles and corresponding solutions. This review will deepen our understanding of the relationship between ferroptosis and breast cancer, and provide new insights into breast cancer-related therapeutic strategies.

Estrogen Receptor Beta (ERβ) Maintains Mitochondrial Network Regulating Invasiveness in an Obesity-Related Inflammation Condition in Breast Cancer

Obesity, a physiological situation where different proinflammatory cytokines and hormones are secreted, is a major risk factor for breast cancer. Mitochondrial functionality exhibits a relevant role in the tumorigenic potential of a cancer cell. In the present study, it has been examined the influence of an obesity-related inflammation ELIT treatment (17β-estradiol, leptin, IL-6, and TNFα), which aims to stimulate the hormonal conditions of a postmenopausal obese woman on the mitochondrial functionality and invasiveness of MCF7 and T47D breast cancer cell lines, which display a different ratio of both estrogen receptor isoforms, ERα and ERβ. The results showed a decrease in mitochondrial functionality, with an increase in oxidative stress and invasiveness and motility, in the MCF7 cell line (high ERα/ERβ ratio) compared to a maintained status in the T47D cell line (low ERα/ERβ ratio) after ELIT treatment. In addition, breast cancer biopsies were analyzed, showing that breast tumors of obese patients present a high positive correlation between IL-6 receptor and ERβ and have an increased expression of cytokines, antioxidant enzymes, and mitochondrial biogenesis and dynamics genes. Altogether, giving special importance to ERβ in the pathology of obese patients with breast cancer is necessary, approaching to personalized medicine.

A case-control study in France showing that a pro-inflammatory diet is associated with a higher risk of breast cancer

Dietary regimens promoting inflammatory conditions have been implicated in breast cancer development, but studies on the association between pro-inflammatory diet and breast cancer risk have reported inconsistent results. We investigated the association between the inflammatory potential of diet and breast cancer risk in a case-control study in France including 872 breast cancer cases and 966 population controls. All women completed a food frequency questionnaire that was used to compute a Dietary Inflammatory Index (DII) based on the inflammatory weight of 33 dietary components. The DII ranged from a median of - 3.22 in the lowest quartile (anti-inflammatory) to + 2.96 in the highest quartile (pro-inflammatory). The odds ratio contrasting quartile 4 to quartile 1 was 1.31 (95% CI 1.00, 1.73; p-trend = 0.02). Slightly higher odds ratios were observed in post-menopausal women, particularly those with body mass index > 25 kg/m2 (odds ratio 1.62; 95% CI 0.92, 2.83; p-trend = 0.02), and among ever smokers (odds ratio 1.71; 95% CI 1.11, 2.65; p-trend 0.01). The analyses by breast cancer subtype showed that the DII was associated with breast tumors that expressed either the estrogen (ER) or progesterone (PR) hormone receptors or the Human Epidermal Growth Factor Receptor-2 (HER2), but no association was seen for the triple negative breast tumor subtype. Our results add further evidence that a pro-inflammatory diet is associated with breast cancer risk with possible effect variation according to tumor subtype.

The Role of Immune Cells in Breast Tissue and Immunotherapy for the Treatment of Breast Cancer

Immune cells are present in normal breast tissue and in breast carcinoma. The nature and distribution of the immune cell subtypes in these tissues are reviewed to promote a better understanding of their important role in breast cancer prevention and treatment. We conducted a review of the literature to define the type, location, distribution, and role of immune cells in normal breast tissue and in in situ and invasive breast cancer. Immune cells in normal breast tissue are located predominantly within the epithelial component in breast ductal lobules. Immune cell subtypes representing innate immunity (NK, CD68+, and CD11c+ cells) and adaptive immunity (most commonly CD8+, but CD4+ and CD20+ as well) are present; CD8+ cells are the most common subtype and are primarily effector memory cells. Immune cells may recognize neoantigens and endogenous and exogenous ligands and may serve in chronic inflammation and immunosurveillance. Progression to breast cancer is characterized by increased immune cell infiltrates in tumor parenchyma and stroma, including CD4+ and CD8+ granzyme B+ cytotoxic T cells, B cells, macrophages and dendritic cells. Tumor-infiltrating lymphocytes in breast cancer may serve as prognostic indicators for response to chemotherapy and for survival. Experimental strategies of adoptive transfer of breast tumor-infiltrating lymphocyte may allow regression of metastatic breast cancer and encourage development of innovative T-cell strategies for the immunotherapy of breast cancer. In conclusion, immune cells in breast tissues play an important role throughout breast carcinogenesis. An understanding of these roles has important implications for the prevention and the treatment of breast cancer.

Effects of systemic inflammation on relapse in early breast cancer

Chronic inflammation has been a proposed mechanism of resistance to aromatase inhibitors in breast cancer. Stratifying by HER2 status, a matched case-control study from the Wellness After Breast Cancer-II cohort was performed to assess whether or not elevated serum inflammatory biomarkers (C-Reactive protein [CRP], interleukin-6 [IL-6], and serum amyloid A [SAA]) and/or the presence of a high-risk IL-6 promoter genotype were associated with recurrence of hormone receptor positive (HR+) early breast cancer. Estrogen levels were also measured and correlated with biomarkers and disease outcomes. CRP and SAA were significantly associated with an increased risk of recurrence in the HR+/HER2− group, but not the HR+/HER2+ group. Mean serum estrogen levels were non-significantly elevated in patients who relapsed vs. non-relapsed patients. Surprisingly, high-risk IL-6 promoter polymorphisms were strongly associated with HER2+ breast cancer relapse, which has potential therapeutic implications, as elevated intracellular IL-6 has been associated with trastuzumab resistance in pre-clinical models.

Dietary antioxidants and fibre intake and depressive symptoms in Iranian adolescent girls

OBJECTIVE

To investigate the cross-sectional association between dietary intakes of antioxidants and fibre and depressive symptoms among Iranian adolescent girls.

DESIGN

A cross-sectional population-based study.

SETTING

Primary schools in two different cities located in northeastern Iran (Mashhad and Sabzevar).

PARTICIPANTS

A total of 988 adolescent girls aged 12-18 years were included in the study.

RESULTS

Subjects with no or minimal depression symptoms had significantly higher dietary intakes of α-carotene (P = 0·01), β-carotene (P = 0·006), lutein (P = 0·03) and vitamin C (P = 0·04) when compared with subjects with mild-to-severe depression symptoms. Soluble dietary fibre and insoluble dietary fibre intakes were also significantly higher in healthy adolescents compared with those with depression symptoms (P < 0·001). In multivariate-adjusted model 2, the OR (95 % CI) of depressive symptoms were 0·61 (95 % CI 0·37, 1·01), 0·42 (95 % CI 0·26, 0·69), 0·50 (95 % CI 0·31, 0·79), 0·71 (95 % CI 0·44, 1·15), 0·51 (95 % CI 0·32, 0·82) and 0·42 (95 % CI 0·25, 0·68) for the highest v. lowest quartile of vitamin C, β-carotene, α-carotene, lutein, soluble dietary fibre and insoluble dietary fibre cereal intakes, respectively.

CONCLUSIONS

Dietary intake of some antioxidants and dietary fibre intake was inversely associated with depression symptoms among Iranian adolescent girls.

D. Custódio I, Silva ATF, C. C. Ferreira I, C. Marinho E, C. Caixeta D, V. Souza A, R. Teixeira R, Araújo TG, Shivappa N, R. Hébert J, Paiva CE, S. Espíndola F, Goulart LR, C. P. Maia Y. Overweight Women with Breast Cancer on Chemotherapy Have More Unfavorable Inflammatory and Oxidative Stress Profiles

Chronic inflammation and redox imbalance are strongly influenced by diet and nutritional status, and both are risk factors for tumor development. This prospective study aimed to explore the associations between inflammatory and antioxidant markers and nutritional status in women with breast cancer undergoing chemotherapy. The women were evaluated at three times: T0, after the infusion of the first cycle; T1, after infusion of the intermediate cycle; and T2, after the infusion of the last chemotherapy cycle. The consumption of antioxidant nutrients and the Total Dietary Antioxidant Capacity reduced between T0 and T2 and the Dietary Inflammatory Index scores increased throughout the chemotherapy. Blood samples taken at the end of the chemotherapy showed lower levels of glutathione reductase and reduced glutathione, with greater quantification of the transcripts for Interleukin-6 and Tumor Necrosis Factor α. It should be emphasized that the Total Dietary Antioxidant Capacity is lower and the Dietary Inflammatory Index is higher in the group of overweight patients at the end of the follow-up, besides showing lower levels of the redox status, especially the plasma levels of glutathione reductase (p = 0.039). In addition, trends towards higher transcriptional levels of cytokines in peripheral blood were observed more often in overweight women than in non-overweight women. In this study of 55 women with breast cancer, nine (16%) with metastases, diet became more pro-inflammatory with fewer antioxidants during the chemotherapy. Briefly, we have shown that chemotherapy is critical for high-risk overweight women due to their reduced intake of antioxidant nutrients, generating greater inflammatory and oxidative stress profiles, suggesting the adoption of healthier dietary practices by women with breast cancer throughout their chemotherapy.

Gaussian Graphical Models Identified Food Intake Networks among Iranian Women with and without Breast Cancer: A Case-Control Study

BACKGROUND

Dietary patterns may be an important predictor of breast cancer risk. However, they cannot completely explain the pairwise correlations among foods. The purpose of this study is to compare food intake networks derived by Gaussian Graphical Models (GGMs) for women with and without breast cancer to better understand how foods are consumed in relation to each other according to disease status.

METHODS

A total of 134 women with breast cancer and 267 hospital controls were selected from referral hospitals of Tehran, Iran. Dietary intakes were evaluated by using a validated 168 food-items semi-quantitative food frequency questionnaire. GGMs were applied to log-transformed intakes of 28 food groups to construct outcome-specific food networks.

RESULTS

Among cases, a main network containing intakes of 12 central food groups (vegetables, fruits, nuts and seeds, olive oil and olive, processed meat, sweets, salt, soft drinks, fried potatoes, pickles, low-fat dairy, pizza) was detected. In controls, a main network including six central food groups (liquid oils, vegetables, fruits, sweets, fried potatoes and soft drinks) was identified.

CONCLUSIONS

The findings of this study revealed a difference in GGM-identified networks graphs between cases and controls. Overall, GGM may provide additional understanding of relationships between diet and health.

IL6/STAT3 Signaling Hijacks Estrogen Receptor α Enhancers to Drive Breast Cancer Metastasis

The cytokine interleukin-6 (IL6) and its downstream effector STAT3 constitute a key oncogenic pathway, which has been thought to be functionally connected to estrogen receptor α (ER) in breast cancer. We demonstrate that IL6/STAT3 signaling drives metastasis in ER+ breast cancer independent of ER. STAT3 hijacks a subset of ER enhancers to drive a distinct transcriptional program. Although these enhancers are shared by both STAT3 and ER, IL6/STAT3 activity is refractory to standard ER-targeted therapies. Instead, inhibition of STAT3 activity using the JAK inhibitor ruxolitinib decreases breast cancer invasion in vivo. Therefore, IL6/STAT3 and ER oncogenic pathways are functionally decoupled, highlighting the potential of IL6/STAT3-targeted therapies in ER+ breast cancer.

Lessons from Hippocrates: Time to Change the Cancer Paradigm

The ultimate goal of all medical activity is to restore patients to a state of complete physical, mental, and social wellbeing. In cancer, it is assumed that this can only be obtained through the complete eradication of the tumor burden. So far, this strategy has led to a substantial improvement in cancer survival rates. Despite this, more than 9 million people die from cancer every year. Therefore, we need to accept that our current cancer treatment paradigm is obsolete and must be changed. The new paradigm should reflect that cancer is a systemic disease, which affects an individual patient living in a particular social reality, rather than an invading organism or a mere cluster of mutated cells that need to be eradicated. This Hippocratic holistic view will ultimately lead to an improvement in health and wellbeing in cancer patients. They deserve nothing less.

Are Oxidative Stress and Inflammation Mediators of Bone Loss Due to Estrogen Deficiency? A Review of Current Evidence

Osteoporosis is one of the major health issues associated with menopause-related estrogen deficiency. Various reports suggest that the hormonal changes related to menopausal transition may lead to the derangement of redox homeostasis and ultimately oxidative stress. Estrogen deficiency and oxidative stress may enhance the expression of genes involved in inflammation. All these factors may contribute, in synergy, to the development of postmenopausal osteoporosis. Previous studies suggest that estrogen may act as an antioxidant to protect the bone against oxidative stress, and as an antiinflammatory agent in suppressing pro-inflammatory and pro-osteoclastic cytokines. Thus, the focus of the current review is to examine the relationship between estrogen deficiency, oxidative stress and inflammation, and the impacts of these phenomena on skeletal health in postmenopausal women.

Molecular Links between Central Obesity and Breast Cancer

Worldwide, breast cancer (BC) is the most common malignancy in women, in regard to incidence and mortality. In recent years, the negative role of obesity during BC development and progression has been made abundantly clear in several studies. However, the distribution of body fat may be more important to analyze than the overall body weight. In our review of literature, we reported some key findings regarding the role of obesity in BC development, but focused more on central adiposity. Firstly, the adipose microenvironment in obese people bears many similarities with the tumor microenvironment, in respect to associated cellular composition, chronic low-grade inflammation, and high ratio of reactive oxygen species to antioxidants. Secondly, the adipose tissue functions as an endocrine organ, which in obese people produces a high level of tumor-promoting hormones, such as leptin and estrogen, and a low level of the tumor suppressor hormone, adiponectin. As follows, in BC this leads to the activation of oncogenic signaling pathways: NFκB, JAK, STAT3, AKT. Moreover, overall obesity, but especially central obesity, promotes a systemic and local low grade chronic inflammation that further stimulates the increase of tumor-promoting oxidative stress. Lastly, there is a constant exchange of information between BC cells and adipocytes, mediated especially by extracellular vesicles, and which changes the transcription profile of both cell types to an oncogenic one with the help of regulatory non-coding RNAs.

The weight of obesity in breast cancer progression and metastasis: Clinical and molecular perspectives

The escalating epidemic of overweight and obesity is currently recognized as one of the most significant health and economic concern worldwide. At the present time, over 1.9 billion adults and more than 600 million people can be, respectively, classified as overweight or obese, and numbers will continue to increase in the coming decades. This alarming scenario implies important clinical implications since excessive adiposity can progressively cause and/or exacerbate a wide spectrum of co-morbidities, including type 2 diabetes mellitus, hypertension, cardiovascular disease, and even certain types of cancer, including breast cancer. Indeed, pathological remodelling of white adipose tissue and increased levels of fat-specific cytokines (mainly leptin), as a consequence of the obesity condition, have been associated with several hallmarks of breast cancer, such as sustained proliferative signaling, cellular energetics, inflammation, angiogenesis, activating invasion and metastasis. Different preclinical and clinical data have provided evidence indicating that obesity may worsen the incidence, the severity, and the mortality of breast cancer. In the present review, we will discuss the epidemiological connection between obesity and breast cancer progression and metastasis and we will highlight the candidate players involved in this dangerous relationship. Since the major cause of death from cancer is due to widespread metastases, understanding these complex mechanisms will provide insights for establishing new therapeutic interventions to prevent/blunt the effects of obesity and thwart breast tumor progression and metastatic growth.

Serum evaluation of leptin, IL-6, IGF-1 and estrogen in obese bitches with early stages of mammary carcinoma

ABSTRACT The aim of this study was to relate the serum concentration IL-6, IGF-1, leptin and estrogen in non-castrated bitches with or without overweight and early stage mammary carcinomas. Forty-three bitches were divided into four groups, two groups without mammary carcinomas with and without overweight, and two groups with mammary carcinomas with and without overweight. Overweight bitches, with or without mammary carcinomas, were statistically different from bitches by ideal weight, in relation to ECC, IMCC and body fat percentages (P< 0.0001). There was a positive correlation between ECC and IMCC (P< 0.0001), ECC and % GC (P< 0.0001), and IMCC and % GC (P< 0.0001). A positive correlation was found between serum leptin and IL-6 (P= 0.0451) and leptin and IGF-1 (P= 0.05). A positive correlation (P= 0.0053) between ECC and leptin was found in the analysis of body evaluation methods and serum concentrations, and a negative correlation between ECC and IL-6 (P= 0.0435). Among the fat percentage and the leptin concentration, there was a positive correlation (P= 0.0016), as found between the IMCC and leptin (P= 0, 0209). In this study, no association was observed between excessive weight and the presence of early stage mammary carcinomas.

Linking obesity-induced leptin-signaling pathways to common endocrine-related cancers in women

Obesity is related to many major diseases and cancers. Women have higher rates of obesity and obesity is linked to commonly occurring cancers in women. However, there is a lack of knowledge of the unique mechanism(s) involved in each type of cancer. The objective of this review is to highlight the need for novel experimental approaches and a better understanding of the common and unique pathways to resolve controversies regarding the role of obesity in cancer. In women, there is a link between hormones and obesity-associated genes in cancer development. Leptin is an obesity-associated gene that has been studied extensively in cancers; however, whether the defect is in the leptin gene or in its signaling pathways remains unclear. Both leptin and its receptor have been positively correlated with cancer progression in some endocrine-related cancers in women. This review offers an up-to-date and cohesive review of both upstream and downstream pathways of leptin signaling in cancer and a comprehensive picture of cancer pathogenesis in light of current evidence of leptin effects in several major types of cancer. This work is intended to aid in the design of better therapeutic strategies for obese/overweight women with cancer.

Obesity-Linked Cancers: Current Knowledge, Challenges and Limitations in Mechanistic Studies and Rodent Models

The worldwide prevalence of obesity has doubled during the last 50 years, and according to the World Obesity Federation, one third of the people on Earth will be obese by the year 2025. Obesity is described as a chronic, relapsing and multifactorial disease that causes metabolic, biomechanical, and psychosocial health consequences. Growing evidence suggests that obesity is a risk factor for multiple cancer types and rivals smoking as the leading preventable cause for cancer incidence and mortality. The epidemic of obesity will likely generate a new wave of obesity-related cancers with high aggressiveness and shortened latency. Observational studies have shown that from cancer risk to disease prognosis, an individual with obesity is consistently ranked worse compared to their lean counterpart. Mechanistic studies identified similar sets of abnormalities under obesity that may lead to cancer development, including ectopic fat storage, altered adipokine profiles, hormone fluctuations and meta-inflammation, but could not explain how these common mechanisms produce over 13 different cancer types. A major hurdle in the mechanistic underpinning of obesity-related cancer is the lack of suitable pre-clinical models that spontaneously develop obesity-linked cancers like humans. Current approaches and animal models fall short when discerning the confounders that often coexist in obesity. In this mini-review, we will briefly survey advances in the different obesity-linked cancers and discuss the challenges and limitations in the rodent models employed to study their relationship. We will also provide our perspectives on the future of obesity-linked cancer research.

Fecal Akkermansia muciniphila Is Associated with Body Composition and Microbiota Diversity in Overweight and Obese Women with Breast Cancer Participating in a Presurgical Weight Loss Trial

BACKGROUND

Akkermansia muciniphila (AM) is a gram-negative, mucin-degrading bacteria inhabiting the gastrointestinal tract associated with host phenotypes and disease states.

OBJECTIVE

Explore characteristics of overweight and obese female early-stage (0 to II) breast cancer patients with low AM relative abundance (LAM) vs high (HAM) enrolled in a presurgical weight-loss trial.

DESIGN

Secondary analysis of pooled participants in a randomized controlled trial (NCT02224807).

PARTICIPANTS/SETTING

During the period from 2014 to 2017, 32 female patients with breast cancer were randomized to weight-loss or attention-control arms from time of diagnosis-to-lumpectomy (mean=30±9 days).

INTERVENTION

All were instructed to correct nutrient deficiencies via food sources and on upper-body exercises. The weight-loss group received additional guidance to promote 0.5 to 1 kg/wk weight-loss via energy restriction and aerobic exercise.

MAIN OUTCOME MEASURES

At baseline and follow-up, sera, fecal samples, two-24 hour dietary recalls and dual x-ray absorptiometry were obtained. Bacterial DNA was isolated from feces and polymerase chain reaction (16S) amplified. Inflammatory cytokines were measured in sera.

STATISTICAL ANALYSES PERFORMED

Differences between LAM and HAM participants were analyzed using t tests and nonparametric tests. Spearman correlations explored relationships between continuous variables.

RESULTS

Participants were aged 61±9 years with body mass index 34.8±6. Mean AM relative abundance was 0.02% (0.007% to 0.06%) and 1.59% (0.59% to 13.57%) for LAM and HAM participants, respectively. At baseline, women with HAM vs LAM had lower fat mass (38.9±11.2 kg vs 46.4±9.0 kg; P=0.044). Alpha diversity (ie, species richness) was higher in women with HAM (360.8±84.8 vs 282.4±69.6; P=0.008) at baseline, but attenuated after weight-loss (P=0.058). At baseline, interleukin-6 level was associated with species richness (ρ=-0.471, P=0.008) and fat mass (ρ=0.529, P=0.002), but not AM. Change in total dietary fiber was positively associated with AM in LAM (ρ=0.626, P=0.002), but not HAM (ρ=0.436, P=0.180) participants.

CONCLUSIONS

Among women with early-stage breast cancer, body composition is associated with AM, microbiota diversity, and interleukin-6 level. AM may mediate the effects of dietary fiber in improving microbiota composition.

Long-term exposure to road traffic noise and incidence of breast cancer: a cohort study

Background

Exposure to road traffic noise was associated with increased risk of estrogen receptor (ER)-negative (ER-) breast cancer in a previous cohort study, but not with overall or ER-positive (ER+) breast cancer, or breast cancer prognosis. We examined the association between long-term exposure to road traffic noise and incidence of breast cancer, overall and by ER and progesterone receptor (PR) status.

Methods

We used the data from a nationwide Danish Nurse Cohort on 22,466 female nurses (age > 44 years) who at recruitment in 1993 or 1999 reported information on breast cancer risk factors. We obtained data on the incidence of breast cancer from the Danish Cancer Registry, and on breast cancer subtypes by ER and PR status from the Danish Breast Cancer Cooperative Group, up to 31 December 2012. Road traffic noise levels at the nurses’ residences were estimated by the Nord2000 method between 1970 and 2013 as annual means of a weighted 24 h average (L_den) at the most exposed facade. We used time-varying Cox regression to analyze the associations between the 24-year, 10-year, and 1-year mean of L_den and breast cancer, separately for total breast cancer and by ER and PR status.

Results

Of the 22,466 women, 1193 developed breast cancer in total during 353,775 person-years of follow up, of whom 611 had complete information on ER and PR status. For each 10 dB increase in 24-year mean noise levels at their residence, we found a statistically significant 10% (hazard ratio and 95% confidence interval 1.10; 1.00–1.20) increase in total breast cancer incidence and a 17% (1.17; 1.02–1.33) increase in analyses based on 611 breast cancer cases with complete ER and PR information. We found positive, statistically significant association between noise levels and ER+ (1.23; 1.06–1.43, N = 494) but not ER- (0.93; 0.70–1.25, N = 117) breast cancers, and a stronger association between noise levels and PR+ (1.21; 1.02–1.42, N = 393) than between noise levels and PR- (1.10; 0.89–1.37, N = 218) breast cancers. Association between noise and ER+ breast cancer was statistically significantly stronger in nurses working night shifts (3.36; 1.48–7.63) than in those not working at night (1.21; 1.02–1.43) (p value for interaction = 0.05).

Conclusion

Long-term exposure to road traffic noise may increase risk of ER+ breast cancer.

Electronic supplementary material

The online version of this article (10.1186/s13058-018-1047-2) contains supplementary material, which is available to authorized users.

Pathogenesis and Treatment Options of Cancer Related Anemia: Perspective for a Targeted Mechanism-Based Approach

Cancer-related anemia (CRA) is a common sign occurring in more than 30% of cancer patients at diagnosis before the initiation of antineoplastic therapy. CRA has a relevant influence on survival, disease progression, treatment efficacy, and the patients' quality of life. It is more often detected in patients with advanced stage disease, where it represents a specific symptom of the neoplastic disease, as a consequence of chronic inflammation. In fact, CRA is characterized by biological and hematologic features that resemble those described in anemia associated to chronic inflammatory disease. Proinflammatory cytokine, mainly IL-6, which are released by both tumor and immune cells, play a pivotal action in CRA etiopathogenesis: they promote alterations in erythroid progenitor proliferation, erythropoietin (EPO) production, survival of circulating erythrocytes, iron balance, redox status, and energy metabolism, all of which can lead to anemia. The discovery of hepcidin allowed a greater knowledge of the relationships between immune cells, iron metabolism, and anemia in chronic inflammatory diseases. Additionally, chronic inflammation influences a compromised nutritional status, which in turn might induce or contribute to CRA. In the present review we examine the multifactorial pathogenesis of CRA discussing the main and novel mechanisms by which immune, nutritional, and metabolic components affect its onset and severity. Moreover, we analyze the status of the art and the perspective for the treatment of CRA. Notably, despite the high incidence and clinical relevance of CRA, controlled clinical studies testing the most appropriate treatment for CRA are scarce, and its management in clinical practice remains challenging. The present review may be useful to indicate the development of an effective approach based on a detailed assessment of all factors potentially involved in the pathogenesis of CRA. This mechanism-based approach is essential for clinicians to plan a safe, targeted, and successful therapy, thereby promoting a relevant amelioration of patients' quality of life.

Dietary patterns and breast cancer risk among Iranian women: A case-control study

AIM

Breast cancer is the most common cancer among women worldwide. Most previous studies focused on individual nutrients or foods rather than overall dietary patterns. We aimed to assess the association between major dietary patterns and breast cancer risk.

METHOD

In a hospital-based case-control study, 134 women diagnosed as breast cancer and 267 controls were recruited from referral hospitals in Tehran, Iran. Dietary intakes were evaluated by using a validated 168-item food frequency questionnaire. Dietary pattern were identified by factor analysis. Odds ratios (OR) were estimated using logistic regression.

RESULTS

Two dietary patterns were extracted: healthy and unhealthy. The "Healthy" dietary pattern was loaded for high consumptions of fruits, vegetables, seeds, legume, fish and sea foods, whole grains, liquid oils, olive oils and olive and lack of salt intake. "Unhealthy" dietary pattern was characterized by high factor loadings for sweets, soft drinks, mayonnaise, solid oils, processed meat, fried and boiled potato and salt intake. In multivariate logistic regression analyses, the healthy dietary pattern was not associated with breast cancer risk (OR: 0.83; 95%CI: 0.36, 1.89; P-trend = 0.50), while women in the highest quartile of the unhealthy dietary pattern had a significantly increased breast cancer risk (OR: 2.21; 95%CI: 1.04, 4.690; P-trend = 0.009). When stratified by menopausal status, unhealthy dietary pattern showed inverse association with breast cancer risk only among post-menopausal women (OR: 3.56; 95%CI: 1.16, 10.95; P-trend = 0.008).

CONCLUSIONS

Our findings showed that an unhealthy dietary pattern might be associated with higher risk of breast among Iranian women.

Signaling pathways and steroid receptors modulating estrogen receptor α function in breast cancer

Estrogen receptor α (ER) is the major driver of ∼75% of breast cancers, and multiple ER targeting drugs are routinely used clinically to treat patients with ER+ breast cancer. However, many patients relapse on these targeted therapies and ultimately develop metastatic and incurable disease, and understanding the mechanisms leading to drug resistance is consequently of utmost importance. It is now clear that, in addition to estrogens, ER function is modulated by other steroid receptors and multiple signaling pathways (e.g., growth factor and cytokine signaling), and many of these pathways affect drug resistance and patient outcome. Here, we review the mechanisms through which these pathways impact ER function and drug resistance as well as discuss the clinical implications.

Association between Dietary Inflammatory Index (DII) and Risk of Breast Cancer: a Case-Control Study

Background:

Breast cancer (BrCa) is the most common cancer among women worldwide and is the second leading cause of cancer-related death in women, in developed countries. This cancer is among the top five most common cancers in Iran. Studies have shown that dietary components are implicated in the etiology of BrCa. The existence of molecular connections between inflammation and BrCa has been demonstrated via different bimolecular events.

Methods:

We examined the ability of the dietary inflammatory index (DIITM) to predict the risk of BrCa. This included 145 cases and 148 controls, who attended the specialized centers. DII scores were computed based on dietary intake assessed using a 168-item FFQ. Logistic regression models were used to estimate multivariable ORs.

Results:

Modeling DII as a continuous variable in relation to risk of BrCa showed a positive association after adjustment for age and energy (OR=1.76; 95% CI=1.43-2.18); and were nearly identical in the multivariable analyses (OR=1.80; 95% CI=1.42-2.28). DII as tertiles, and adjusting for age and energy, subjects in tertile 3 had an OR of 6.94 (95% CI= 3.26-14.79; P-trend ≤0.0001) in comparison to subjects in tertile 1. After multivariable adjustment, results were essentially identical as in the model adjusting for age and energy (OR tertile 3vs1=7.24; 95% CI=3.14-16.68; P-trend ≤0.001). Sub group analyses revealed similar positive associations with HER 2 receptor +ve, progesterone receptor +ve, estrogen receptor +ve and lymph node invasive cases.

Conclusion:

Subjects who consumed a more pro-inflammatory diet were at increased risk of BrCa compared to those who consumed a more anti-inflammatory diet.

Dietary fiber and health outcomes: an umbrella review of systematic reviews and meta-analyses

Background

Several studies have suggested that higher consumption of dietary fiber is beneficial for a variety of health outcomes. However, many results have been inconclusive and, to our knowledge, there has been no attempt to systematically capture the breadth of outcomes associated with dietary fiber intake or to systematically assess the quality and the strength of the evidence on the associations of dietary fiber intake and different health outcomes or medical conditions.

Objective

The aim of this study was to describe the diverse health outcomes convincingly associated with dietary fiber consumption.

Design

This was an umbrella review of systematic reviews with meta-analysis of observational studies. For each association, random-effects summary effect size, 95% CIs, and 95% prediction intervals were estimated. We also assessed heterogeneity, evidence for small-study effect, and evidence for excess significance bias. We used these metrics to evaluate the credibility of the identified evidence.

Results

Our literature search identified 1351 abstracts. Of these, 18 meta-analyses including a total of 298 prospective observational studies and 21 outcomes were included. Outcomes studied included cancer and precancer lesions (n = 12), cardiovascular diseases (CVDs; n = 3), all-cause and specific-cause mortality (n = 4), type 2 diabetes (n = 1), and Crohn disease (n = 1). Overall, 6 (29%) of the 21 eligible outcomes reported highly significant summary results (P < 1 × 10-6); these included CVD and CVD mortality, coronary artery disease, pancreatic cancer, and gastric cancer. Overall, 3 of 21 (14%) outcomes presented convincing evidence (pancreatic cancer, CVD mortality, and all-cause mortality), but only CVD and all-cause mortality were based on prospective studies. Two other outcomes (10%), CVD and coronary artery disease, presented highly suggestive evidence based on prospective studies.

Conclusion

Our results support dietary recommendations that promote higher fiber intake as part of a healthy diet.

The potential role of leptin in tumor invasion and metastasis

The adipocyte-released hormone-like cytokine/adipokine leptin behaves differently in obesity compared to its functions in the normal healthy state. In obese individuals, elevated leptin levels act as a pro-inflammatory adipokine and are associated with certain types of cancers. Further, a growing body of evidence suggests that higher circulating leptin concentrations and/or elevated expression of leptin receptors (Ob-R) in tumors may be poor prognostic factors. Although the underlying pathological mechanisms of leptin's association with poor prognosis are not clear, leptin can impact the tumor microenvironment in several ways. For example, leptin is associated with a number of biological components that could lead to tumor cell invasion and distant metastasis. This includes interactions with carcinoma-associated fibroblasts, tumor promoting effects of infiltrating macrophages, activation of matrix metalloproteinases, transforming growth factor-β signaling, etc. Recent studies also have shown that leptin plays a role in the epithelial-mesenchymal transition, an important phenomenon for cancer cell migration and/or metastasis. Furthermore, leptin's potentiating effects on insulin-like growth factor-I, epidermal growth factor receptor and HER2/neu have been reported. Regarding unfavorable prognosis, leptin has been shown to influence both adenocarcinomas and squamous cell carcinomas. Features of poor prognosis such as tumor invasion, lymph node involvement and distant metastasis have been recorded in several cancer types with higher levels of leptin and/or Ob-R. This review will describe the current scenario in a precise manner. In general, obesity indicates poor prognosis in cancer patients.

Activated Oncogenic Pathway Modifies Iron Network in Breast Epithelial Cells: A Dynamic Modeling Perspective

Dysregulation of iron metabolism in cancer is well documented and it has been suggested that there is interdependence between excess iron and increased cancer incidence and progression. In an effort to better understand the linkages between iron metabolism and breast cancer, a predictive mathematical model of an expanded iron homeostasis pathway was constructed that includes species involved in iron utilization, oxidative stress response and oncogenic pathways. The model leads to three predictions. The first is that overexpression of iron regulatory protein 2 (IRP2) recapitulates many aspects of the alterations in free iron and iron-related proteins in cancer cells without affecting the oxidative stress response or the oncogenic pathways included in the model. This prediction was validated by experimentation. The second prediction is that iron-related proteins are dramatically affected by mitochondrial ferritin overexpression. This prediction was validated by results in the pertinent literature not used for model construction. The third prediction is that oncogenic Ras pathways contribute to altered iron homeostasis in cancer cells. This prediction was validated by a combination of simulation experiments of Ras overexpression and catalase knockout in conjunction with the literature. The model successfully captures key aspects of iron metabolism in breast cancer cells and provides a framework upon which more detailed models can be built.

Iron is required for cellular metabolism and growth, but can be toxic due to its ability to cause high oxidative stress and consequently DNA damage. To prevent damage, all organisms that require iron have developed mechanisms to tightly control iron levels. Dysregulation of iron metabolism is detrimental and can contribute to a wide range of diseases, including cancer. This paper presents a predictive mathematical model of iron regulation linked to iron utilization, oxidative stress, and the oncogenic response specific to normal breast epithelial cells. The model uses a discrete modeling framework to generate novel biological hypotheses for an investigation of how normal breast cells become malignant cells, capturing a breast cancer phenotype of iron homeostasis through overexpression and knockout simulations. The new biology discovered is (1) IRP2 overexpression alters the iron homeostasis pathway in breast cells, without affecting the oxidative stress response or oncogenic pathways, (2) an activated oncogenic pathway disrupts iron regulation in breast cancer cells.

Obesity-associated Breast Cancer: Analysis of risk factors

Several studies show that a significantly stronger association is obvious between increased body mass index (BMI) and higher breast cancer incidence. Furthermore, obese women are at higher risk of all-cause and breast cancer specific mortality when compared to non-obese women with breast cancer. In this context, increased levels of estrogens due to excessive aromatization activity of the adipose tissue, overexpression of pro-inflammatory cytokines, insulin resistance, hyperactivation of insulin-like growth factors (IGFs) pathways, adipocyte-derived adipokines, hypercholesterolemia and excessive oxidative stress contribute to the development of breast cancer in obese women. While higher breast cancer risk with hormone replacement therapy is particularly evident among lean women, in postmenopausal women who are not taking exogenous hormones, general obesity is a significant predictor for breast cancer. Moreover, increased plasma cholesterol leads to accelerated tumor formation and exacerbates their aggressiveness. In contrast to postmenopausal women, premenopausal women with high BMI are inversely associated with breast cancer risk. Nevertheless, life-style of women for breast cancer risk is regulated by avoiding the overweight and a high-fat diet. Estrogen-plus-progestin hormone therapy users for more than 5 years have elevated risks of both invasive ductal and lobular breast cancer. Additionally, these cases are more commonly node-positive and have a higher cancer-related mortality. Collectively, in this chapter, the impacts of obesity-related estrogen, cholesterol, saturated fatty acid, leptin and adiponectin concentrations, aromatase activity, leptin and insulin resistance on breast cancer patients are evaluated. Obesity-related prognostic factors of breast cancer also are discussed at molecular basis.

Oxidant stress as a major determinant of platelet activation in invasive breast cancer

The hypothesis that increased oxidative stress in breast cancer (BC) patients could induce enhanced lipid peroxidation, which, in turn, would contribute to platelet activation and poor clinical outcome is attractive. To address this issue, we investigated pre-surgical urinary 8-iso-prostaglandin (PG)F_2α (marker of in vivo oxidative stress) and 11-dehydro-thromboxane (TX)B₂ (marker of in vivo platelet activation) levels in patients with primary BC (n = 115) compared with control women paired for comorbidities and their association with patients' metabolic profile and clinical prognostic factors. The results obtained showed that presurgical urinary excretion of both biomarkers was enhanced in BC patients compared to controls and was associated with patients' estrogen receptor (ER) expression, but not HER2 status or Ki67 proliferation index. Accordingly, both urinary biomarkers were increased in patients with luminal-like BC molecular subtypes compared with triple negative or HER2-enriched tumors. ER status was an independent predictor of 8-iso-PGF_2α urinary levels, which, in turn, significantly predicted 11-dehydro-TXB₂ urinary levels together with disease stage and ER status. The prognostic value of 11-dehydro-TXB₂ was then evaluated showing a significant correlation with BC pathological response to neoadjuvant treatment. Furthermore, among relapsing patients, those with elevated urinary biomarker levels were more likely to develop distant metastasis rather than local recurrence. In conclusion, we may speculate that enhanced oxidative stress due to estrogen-related mechanisms might cause a condition of persistent platelet activation capable of sustaining BC growth and progression through the release of bioactive stored molecules, ultimately contributing to tumor invasiveness. Further studies specifically addressing this hypothesis are presently needed.

Increased Incidence of Breast Cancer in Postmenopausal Women with High Body Mass Index at the Modena Screening Program

Purpose

We conducted a study to evaluate the relationship between body mass index (BMI) and the risk of breast cancer (BC) and outcome in a population of 14,684 women aged 55 to 69 years eligible to participate in the Mammography Screening Program (MSP) in the Province of Modena, Italy.

Methods

The study population was drawn from women who underwent mammography screening between 2004 and 2006 in the Province of Modena. Women were subdivided into obese, overweight, and normal-weight categories according to BMI and followed until July 31, 2010, to evaluate the BC incidence. The clinicopathological characteristics of BC were also evaluated in different groups of patients classified according to BMI. After BC diagnosis, patients were followed for a median period of 65 (range, 2–104) months. Second events (recurrences and second tumors) were recorded, and the 5-year event-free survival (EFS) was calculated.

Results

After a period of 73 months, 366 cases of BC were diagnosed. Compared with normal-weight women, obese women had a significantly higher incidence of BC (relative risk [RR], 1.32; p=0.040) (RR=1), larger tumors (27% of tumors were larger than T2 size), and more nodal involvement (38.5% of tumors were node-positive). Furthermore, a significantly higher rate of total events was seen in obese women compared with overweight and normal-weight patients, respectively (17.9% vs. 11.4% vs. 10.8%, p=0.032). The 5-year EFS was 89.0%, 89.0%, and 80.0% for normal-weight, overweight, and obese patients, respectively.

Conclusion

We observed a significantly higher risk of BC in obese women among those eligible to participate in the MSP in the Province of Modena. Finally, obese women had more second events and poorer EFS compared to nono bese women.

Low-Grade Inflammation, Oxidative Stress and Risk of Invasive Post-Menopausal Breast Cancer - A Nested Case-Control Study from the Malmö Diet and Cancer Cohort

OBJECTIVE

Although cancer promotes inflammation, the role of inflammation in tumor-genesis is less well established. The aim was to examine if low-grade inflammation is related to post-menopausal breast cancer risk, and if obesity modifies this association.

METHODS

In the Malmö Diet and Cancer cohort, a nested case-control study was defined among 8,513 women free of cancer and aged 55-73 years at baseline (1991-96); 459 were diagnosed with invasive breast cancer during follow-up (until December 31st, 2010). In laboratory analyses of blood from 446 cases, and 885 controls (matched on age and date of blood sampling) we examined systemic inflammation markers: oxidized (ox)-LDL, interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor (TNF)-α, white blood cells, lymphocytes and neutrophils. Odds ratios (OR) and 95% confidence intervals (CI) for breast cancer risk was calculated using multivariable conditional logistic regression.

RESULTS

Inverse associations with breast cancer were seen in fully-adjusted models, for 2nd and 3rd tertiles of ox-LDL, OR (95% CI): 0.65 (0.47-0.90), 0.63 (0.45-0.89) respectively, p-trend = 0.01; and for the 3rd tertile of TNF-α, 0.65 (0.43-0.99), p-trend = 0.04. In contrast, those in the highest IL-1β category had higher risk, 1.71 (1.05-2.79), p-trend = 0.01. Obesity did not modify associations between inflammation biomarkers and breast cancer.

CONCLUSION

Our study does not suggest that low-grade inflammation increase the risk of post-menopausal breast cancer.

8-Oxo-7,8-dihydro-2'-deoxyguanosine and other lesions along the coding strand of the exon 5 of the tumour suppressor gene P53 in a breast cancer case-control study

The next-generation sequencing studies of breast cancer have reported that the tumour suppressor P53 (TP53) gene is mutated in more than 40% of the tumours. We studied the levels of oxidative lesions, including 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), along the coding strand of the exon 5 in breast cancer patients as well as in a reactive oxygen species (ROS)-attacked breast cancer cell line using the ligation-mediated polymerase chain reaction technique. We detected a significant 'in vitro' generation of 8-oxodG between the codons 163 and 175, corresponding to a TP53 region with high mutation prevalence, after treatment with xanthine plus xanthine oxidase, a ROS-generating system. Then, we evaluated the occurrence of oxidative lesions in the DNA-binding domain of the TP53 in the core needle biopsies of 113 of women undergoing breast investigation for diagnostic purpose. An increment of oxidative damage at the -G- residues into the codons 163 and 175 was found in the cancer cases as compared to the controls. We found significant associations with the pathological stage and the histological grade of tumours. As the major news of this study, this largest analysis of genomic footprinting of oxidative lesions at the TP53 sequence level to date provided a first roadmap describing the signatures of oxidative lesions in human breast cancer. Our results provide evidence that the generation of oxidative lesions at single nucleotide resolution is not an event highly stochastic, but causes a characteristic pattern of DNA lesions at the site of mutations in the TP53, suggesting causal relationship between oxidative DNA adducts and breast cancer.

GPER signalling in both cancer-associated fibroblasts and breast cancer cells mediates a feedforward IL1β/IL1R1 response

Cancer-associated fibroblasts (CAFs) contribute to the malignant aggressiveness through secreted factors like IL1β, which may drive pro-tumorigenic inflammatory phenotypes mainly acting via the cognate receptor named IL1R1. Here, we demonstrate that signalling mediated by the G protein estrogen receptor (GPER) triggers IL1β and IL1R1 expression in CAFs and breast cancer cells, respectively. Thereby, ligand-activation of GPER generates a feedforward loop coupling IL1β induction by CAFs to IL1R1 expression by cancer cells, promoting the up-regulation of IL1β/IL1R1 target genes such as PTGES, COX2, RAGE and ABCG2. This regulatory interaction between the two cell types induces migration and invasive features in breast cancer cells including fibroblastoid cytoarchitecture and F-actin reorganization. A better understanding of the mechanisms involved in the regulation of pro-inflammatory cytokines by GPER-integrated estrogen signals may be useful to target these stroma-cancer interactions.

The immune system and hormone-receptor positive breast cancer: Is it really a dead end?

Even if breast cancer has not been traditionally considered an immunogenic tumor, recent data suggest that immunity, and its interaction with tumor cells and tumor microenvironment, might play an important role in this malignancy, in particular in triple negative and HER2+ subtypes. As no consistent data on the potential clinical relevance of tumor infiltrating lymphocytes have been produced in hormone receptor positive (HR+) HER2- breast cancer, the interest in studying immune aspects in this subtype has become less appealing. Nevertheless, some scattered evidence indicates that immunity and inflammation may be implicated in the biology of this subtype as well. In HR+ breast cancer, the interaction between tumor cells and the immune milieu might rely on different mechanisms than in other BC subtypes, involving the modulation of the tumor microenvironment by mutual interplays of endocrine factors, pro-inflammatory status and immune cells. These subtle mechanisms may require more refined methods of evaluation, such as the assessment of tumor infiltrating lymphocytes subpopulations or gene signatures. In this paper we aim to perform a comprehensive review of pre-clinical and clinical data on the interplay between the immune system and breast cancer in the HR+ subtype, to guide further research in the field.

Proinflammatory and Anti-Inflammatory Cytokines Mediated by NF-κB Factor as Prognostic Markers in Mammary Tumors

Inflammation results in the production of cytokines, such as interleukin- (IL-) 4 and IL-10 with immunosuppressive properties or IL-6 and TNF-α with procarcinogenic activity. Furthermore, NF-κB is the major link between inflammation and tumorigenesis. This study verified the interaction between active inflammatory cytokines in the tumor microenvironment and serum of female dogs with mammary tumors and their correlation with the clinicopathological characteristics and overall survival. Measurement of gene expression was performed by qPCR and protein levels by ELISA/Luminex. High gene and protein expression levels of NF-κB, IL-6, and TNF-α were found in association with characteristics that reflect worse prognosis and a negative correlation between TNF-α protein expression and survival time was observed (p < 0.05). In contrast, high gene and protein expression levels of IL-4 and IL-10 were associated with characteristics of better prognosis and an increased level of IL-4 and a longer survival time of animals were obtained (p < 0.05). In addition, there was a positive correlation between TNF-α and IL-6 expression in association with NF-κB. The results show a significant correlation of these cytokines with tumor development, associated with NF-κB expression and cytokines promodulation, showing that these biological factors could be used as predictive and prognostic markers in breast cancer.

Expression of a mutant prohibitin from the aP2 gene promoter leads to obesity-linked tumor development in insulin resistance-dependent manner

A critical unmet need for the study of obesity-linked cancer is the lack of preclinical models that spontaneously develop obesity and cancer sequentially. Prohibitin (PHB) is a pleiotropic protein that has a role in adipose and immune functions. We capitalized on this attribute of PHB to develop a mouse model for obesity-linked tumor. We achieved this by expressing Y114F-PHB (m-PHB) from the aP2 gene promoter for simultaneous manipulation of adipogenic and immune signaling functions. The m-PHB mice develop obesity in a sex-neutral manner, but only male mice develop impaired glucose homeostasis and hyperinsulinemia similar to transgenic mice expressing PHB. Interestingly, only male m-PHB mice develop histiocytosis with lymphadenopathy, suggesting that metabolic dysregulation or m-PHB alone is not sufficient for the tumor development and that both are required for tumorigenesis. Moreover, ovariectomy in female m-PHB mice resulted in impaired glucose homeostasis, hyperinsulinemia and consequently tumor development similar to male m-PHB mice. These changes were not observed in sham-operated control m-Mito-Ob mice, further confirming the role of obesity-related metabolic dysregulation in tumor development in m-PHB mice. Our data provide a proof-of-concept that obesity-associated hyperinsulinemia promotes tumor development by facilitating dormant mutant to manifest and reveals a sex-dimorphic role of PHB in adipose-immune interaction or immunometabolism. Targeting PHB may provide a unique opportunity for the modulation of immunometabolism in obesity, cancer and in immune diseases.

Cancer prevention and therapy through the modulation of the tumor microenvironment

Cancer arises in the context of an in vivo tumor microenvironment. This microenvironment is both a cause and consequence of tumorigenesis. Tumor and host cells co-evolve dynamically through indirect and direct cellular interactions, eliciting multiscale effects on many biological programs, including cellular proliferation, growth, and metabolism, as well as angiogenesis and hypoxia and innate and adaptive immunity. Here we highlight specific biological processes that could be exploited as targets for the prevention and therapy of cancer. Specifically, we describe how inhibition of targets such as cholesterol synthesis and metabolites, reactive oxygen species and hypoxia, macrophage activation and conversion, indoleamine 2,3-dioxygenase regulation of dendritic cells, vascular endothelial growth factor regulation of angiogenesis, fibrosis inhibition, endoglin, and Janus kinase signaling emerge as examples of important potential nexuses in the regulation of tumorigenesis and the tumor microenvironment that can be targeted. We have also identified therapeutic agents as approaches, in particular natural products such as berberine, resveratrol, onionin A, epigallocatechin gallate, genistein, curcumin, naringenin, desoxyrhapontigenin, piperine, and zerumbone, that may warrant further investigation to target the tumor microenvironment for the treatment and/or prevention of cancer.