Resistin as a biomarker linking obesity and inflammation to cancer: potential clinical perspectives

Immunological roles for resistin and related adipokines in obesity-associated tumors

Rationale Obesity is an independent risk factor for the occurrence and development of tumors. Obesity is influenced by signaling of adipokines, which are secreted factors from adipocytes and resident immune cells within adipose tissues that mediate lipid metabolism. More recently, adipokines have been implicated in chronic inflammation as well as in tumor formation and growth. Among them, resistin has received increasing attention in research related to the growth and expansion of solid tumors and hematological cancers through various signaling pathways. Objective and findings We reviewed the physiological, biochemical, and immune functions of adipose tissue, with a focus on the structure and expression of resistin and adipokines within multiple adipose cell types, their signaling pathways and putative effects on tumor cells, as well as their in vivo regulation. Current evidence indicates that adipokines such as resistin act as pro-inflammatory factors to stimulate immune cells which, in turn, promotes tumor angiogenesis, connective tissue proliferation, and matrix fibrosis. Concurrently, in states of metabolic dysfunction and lipotoxicity in obese individuals, the numbers and functions of immune cells are compromised, leading to an immunosuppressive environment that fosters tumor cell survival and weak cancer immune monitoring. Conclusion Adipokines such as resistin are important to the development of obesity-related tumors. Clarifying the roles for obesity-related factors in immune regulation and tumor progression may lead to the discovery of novel anti-tumor strategies for targeting obesity factors such as resistin to limit tumor growth and manage obesity, or both.

LightGBM is an Effective Predictive Model for Postoperative Complications in Gastric Cancer: A Study Integrating Radiomics with Ensemble Learning

Postoperative complications of radical gastrectomy seriously affect postoperative recovery and require accurate risk prediction. Therefore, this study aimed to develop a prediction model specifically tailored to guide perioperative clinical decision-making for postoperative complications in patients with gastric cancer. A retrospective analysis was conducted on patients who underwent radical gastrectomy at the First Affiliated Hospital of Nanjing Medical University between April 2022 and June 2023. A total of 166 patients were enrolled. Patient demographic characteristics, laboratory examination results, and surgical pathological features were recorded. Preoperative abdominal CT scans were used to segment the visceral fat region of the patients through 3Dslicer, a 3D Convolutional Neural Network (3D-CNN) to extract image features and the LASSO regression model was employed for feature selection. Moreover, an ensemble learning strategy was adopted to train the features and predict postoperative complications of gastric cancer. The prediction performance of the LGBM (Light Gradient Boosting Machine), XGB (XGBoost), RF (Random Forest), and GBDT (Gradient Boosting Decision Tree) models was evaluated through fivefold cross-validation. This study successfully constructed a model for predicting early complications following radical gastrectomy based on the optimal algorithm, LGBM. The LGBM model yielded an AUC value of 0.9232 and an accuracy of 87.28% (95% CI, 75.61-98.95%), surpassing the performance of other models. Through ensemble learning and integration of perioperative clinical data and visceral fat radiomics, a predictive LGBM model was established. This model has the potential to facilitate individualized clinical decision-making and the early recovery of patients with gastric cancer post-surgery.

An Updated Review of Resistin and Colorectal Cancer

Resistin is one of the most important adipokines, and its role lies mainly in controlling insulin sensitivity and inflammation. However, over the last years, the study of resistin gained increased popularity since it was proved that there is a considerable relationship between high levels of resistin and obesity as well as obesity-induced diseases, including diabetes, cardiovascular disorders, and cancer. Regarding cancer risk, circulating resistin levels have been correlated with several types of cancer, including colorectal, breast, lung, endometrial, gastroesophageal, prostate, renal, and pancreatic cancer. Colorectal cancer is regarded as a multi-pathway disease. Several pathophysiological features seem to promote colorectal cancer (CRC) such as chronic inflammation, insulin resistance, and obesity. Even though the molecular mechanisms involved in CRC development remain rather vague, it is widely accepted that several biochemical factors promote CRC by releasing augmented pro-inflammatory cytokines, like IGF-I, insulin, sex-steroid hormones, and adipokines. A wide range of research studies has focused on evaluating the impact of circulating resistin levels on CRC risk and determining the efficacy of chemotherapy in CRC patients by measuring resistin levels. Moreover, significant outcomes have emerged regarding the association of specific single nucleotide polymorphisms (SNPs) in the resistin gene and CRC risk. The present study reviewed the role of circulating resistin levels in CRC development and shed light on specific resistin gene SNPs implicated in the disease's development. Finally, we analyzed the impact of resistin levels on the effectiveness of chemotherapy and further discussed whether resistin can be regarded as a valuable biomarker for CRC prognosis and treatment. Resistin is one of the most important adipokines, and its role lies mainly in controlling insulin sensitivity and inflammation. However, over the last years, the study of resistin gained increased popularity since it was proved that there is a considerable relationship between high levels of resistin and obesity as well as obesity-induced diseases, including diabetes, cardiovascular disorders, and cancer. This review discusses the aberrant expression of resistin and its receptors, its diverse downstream signaling, and its impact on tumor growth, metastasis, angiogenesis, and therapy resistance to support its clinical exploitation in biomarker and therapeutic development.

Genetic prediction of the relationship between metabolic syndrome and colorectal cancer risk: a Mendelian randomization study

BACKGROUND

Despite a growing body of observational studies indicating a potential link between metabolic syndrome and colorectal cancer, a definitive causal relationship has yet to be established. This study aimed to elucidate the causal relationship between metabolic syndrome and colorectal cancer through Mendelian randomization.

METHODS

We screened for instrumental variables associated with metabolic syndrome and its diagnostic components and with colorectal cancer through the use of a genome-wide association study database, and conducted a preliminary Mendelian randomization analysis. To corroborate the dependability of our conclusions, an additional dataset was used for replication analysis in a Mendelian randomization method, which was further integrated with a meta-analysis.

RESULTS

Preliminary analysis using the inverse variance weighted method revealed positive correlations between metabolic syndrome (OR [95% CI] = 1.37[1.15-1.63], P = 5.02 × 10-4) and waist circumference (OR [95% CI] = 1.39[1.21-1.61], P = 7.38 × 10-6) and the risk of colorectal cancer. Replication analysis also revealed the same results: metabolic syndrome (OR [95% CI] = 1.24[1.02-1.51], P = 0.030) and waist circumference (OR [95% CI] = 1.23[1.05-1.45], P = 0.013). The meta-analysis results further confirmed the associations between metabolic syndrome (OR [95% CI] = 1.31[1.15-1.49], P < 0.001) and waist circumference (OR [95% CI] = 1.32[1.18-1.47], P < 0.001) and colorectal cancer.

CONCLUSION

Our study indicated that metabolic syndrome increases the risk of CRC, particularly in patients with abdominal obesity.

The effect of resistin on the redox state of breast cancer cells

PURPOSE

Resistin is an inflammatory cytokine secreted mostly by adipocytes and immune cells that plays a role in the development of insulin resistance, diabetes, and cancer. We hypothesized that resistin's inflammatory activity influences the free radical and oxidative stress pathways.

METHODS

We used human breast carcinogenic (MCF-7 and MDA-MB-231) and non-carcinogenic (MCF-10A) cells in this investigation and correlated the absorbed resistin concentration with the change in oxidative stress (TBARS, carbonated proteins) and antioxidant activity (Antioxidant Capacity, SuperOxideDismutase, CATalase, Glutathione Peroxidase).

RESULTS

Resistin was substantially more effective as a prooxidant at lower (12.5 ng/ml) concentrations, than at higher concentrations (25.0 ng/ml). Vitamin C did not appear to be an effective oxidative stress protector at antioxidant concentrations of 5.10-4 M. Leptin, at 100 ng/ml, did not result in conclusive oxidative stress or antioxidant defence stimulation, as expected.

CONCLUSION

Taken together, the findings support resistin's role as a non-oxidative stress marker and a metabolic signaling molecule.

The Role of Local Angiotensin II/Angiotensin Type 1-receptor Mechanisms in Adipose Tissue Dysfunction to Promote Pancreatic Cancer

Obesity and adipose tissue dysfunction are important risk factors for pancreatic cancer. Pancreatic cancer is one of the most lethal cancers globally. The renin-angiotensin system (RAS) is expressed in many tissues, including adipose tissue. Dysregulation of angiotensin II and angiotensin II receptors in adipose tissue through the activation of different signaling pathways leads to adipose tissue dysfunction, including insulin resistance, adipose tissue inflammation, adipocytokines secretion, and metabolic alterations. The pathogenesis of pancreatic cancer remains uncertain. However, there is evidence that dysregulation of local angiotensin II in adipose tissue that occurs in association with obesity is, in part, responsible for the initiation and progression of pancreatic cancer. Due to the role of local angiotensin II in the dysfunction of adipose tissue, angiotensin receptor blockers may be considered a new therapeutic strategy in the amelioration of the complications related to adipose tissue dysfunction and prevention of pancreatic cancer. This review aims to consider the biological roles of local angiotensin II and angiotensin II receptors in adipose tissue dysfunction to promote pancreatic cancer progression with a focus on adipose tissue inflammation and metabolic reprogramming.

The Role of Adipokines in Health and Disease

Adipokines are cell-signaling proteins secreted by adipose tissue that has been related to a low-grade state of inflammation and different pathologies. The present review aims to analyze the role of adipokines in health and disease in order to understand the important functions and effects of these cytokines. For this aim, the present review delves into the type of adipocytes and the cytokines produced, as well as their functions; the relations of adipokines in inflammation and different diseases such as cardiovascular, atherosclerosis, mental diseases, metabolic disorders, cancer, and eating behaviors; and finally, the role of microbiota, nutrition, and physical activity in adipokines is discussed. This information would allow for a better understanding of these important cytokines and their effects on body organisms.

The Modulation of Adipokines, Adipomyokines, and Sleep Disorders on Carcinogenesis

Obesity and sarcopenia, i.e., decreased skeletal muscle mass and function, are global health challenges. Moreover, people with obesity and sedentary lifestyles often have sleep disorders. Despite the potential associations, metabolic disturbances linking obesity, sarcopenia, and sleep disorders with cancer are neither well-defined nor understood fully. Abnormal levels of adipokines and adipomyokines originating from both adipose tissue and skeletal muscles are observed in some patients with obesity, sarcopenia and sleep disorders, as well as in cancer patients. This warrants investigation with respect to carcinogenesis. Adipokines and adipomyokines may exert either pro-carcinogenic or anti-carcinogenic effects. These factors, acting independently or together, may significantly modulate the incidence and progression of cancer. This review indicates that one of the possible pathways influencing the development of cancer may be the mutual relationship between obesity and/or sarcopenia, sleep quantity and quality, and adipokines/adipomyokines excretion. Taking into account the high proportion of persons with obesity and sedentary lifestyles, as well as the associations of these conditions with sleep disturbances, more attention should be paid to the individual and combined effects on cancer pathophysiology.

Obesity and main urologic cancers: Current systematic evidence, novel biological mechanisms, perspectives and challenges

Urologic cancers (UC) account for 13.1% of all new cancer cases and 7.9% of all cancer-related deaths. A growing body of evidence has indicated a potential causal link between obesity and UC. The aim of the present review is to appraise in a critical and integrative manner evidence from meta-analyses and mechanistic studies on the role of obesity in four prevalent UC (kidney-KC, prostate-PC, urinary bladder-UBC, and testicular cancer-TC). Special emphasis is given on Mendelian Randomization Studies (MRS) corroborating a genetic causal association between obesity and UC, as well as on the role of classical and novel adipocytokines. Furthermore, the molecular pathways that link obesity to the development and progression of these cancers are reviewed. Available evidence indicates that obesity confers increased risk for KC, UBC, and advanced PC (20-82%, 10-19%, and 6-14%, respectively), whereas for TC adult height (5-cm increase) may increase the risk by 13%. Obese females tend to be more susceptible to UBC and KC than obese males. MRS have shown that a higher genetic-predicted BMI may be causally linked to KC and UBC but not PC and TC. Biological mechanisms that are involved in the association between excess body weight and UC include the Insulin-like Growth Factor axis, altered availability of sex hormones, chronic inflammation and oxidative stress, abnormal secretion of adipocytokines, ectopic fat deposition, dysbiosis of the gastrointestinal and urinary tract microbiomes and circadian rhythm dysregulation. Anti-hyperglycemic and non-steroidal anti-inflammatory drugs, statins, and adipokine receptor agonists/antagonists show potential as adjuvant cancer therapies. Identifying obesity as a modifiable risk factor for UC may have significant public health implications, allowing clinicians to tailor individualized prevention strategies for patients with excess body weight.

Role of Bioactive Compounds in Obesity: Metabolic Mechanism Focused on Inflammation

Obesity is a disease characterized by an inflammatory process in the adipose tissue due to diverse infiltrated immune cells, an increased secretion of proinflammatory molecules, and a decreased secretion of anti-inflammatory molecules. On the other hand, obesity increases the risk of several diseases, such as cardiovascular diseases, diabetes, and cancer. Their treatment is based on nutritional and pharmacological strategies. However, natural products are currently implemented as complementary and alternative medicine (CAM). Polyphenols and fiber are naturally compounds with potential action to reduce inflammation through several pathways and play an important role in the prevention and treatment of obesity, as well as in other non-communicable diseases. Hence, this review focuses on the recent evidence of the molecular mechanisms of polyphenols and dietary fiber, from Scopus, Science Direct, and PubMed, among others, by using key words and based on recent in vitro and in vivo studies.

Understanding the Co-Epidemic of Obesity and COVID-19: Current Evidence, Comparison with Previous Epidemics, Mechanisms, and Preventive and Therapeutic Perspectives

PURPOSE OF REVIEW

A growing body of evidence suggests that obesity and increased visceral adiposity are strongly and independently linked to adverse outcomes and death due to COVID-19. This review summarizes current epidemiologic data, highlights pathogenetic mechanisms on the association between excess body weight and COVID-19, compares data from previous pandemics, discusses why COVID-19 challenges the "obesity paradox," and presents implications in prevention and treatment as well as future perspectives.

RECENT FINDINGS

Data from meta-analyses based on recent observational studies have indicated that obesity increases the risks of infection from SARS-CoV-2, severe infection and hospitalization, admission to the ICU and need of invasive mechanical ventilation (IMV), and the risk of mortality, particularly in severe obesity. The risks of IMV and mortality associated with obesity are accentuated in younger individuals (age ≤ 50 years old). The meta-inflammation in obesity intersects with and exacerbates underlying pathogenetic mechanisms in COVID-19 through the following mechanisms and factors: (i) impaired innate and adaptive immune responses; (ii) chronic inflammation and oxidative stress; (iii) endothelial dysfunction, hypercoagulability, and aberrant activation of the complement; (iv) overactivation of the renin-angiotensin-aldosterone system; (v) overexpression of the angiotensin-converting enzyme 2 receptor in the adipose tissue; (vi) associated cardiometabolic comorbidities; (vii) vitamin D deficiency; (viii) gut dysbiosis; and (ix) mechanical and psychological issues. Mechanistic and large epidemiologic studies using big data sources with omics data exploring genetic determinants of risk and disease severity as well as large randomized controlled trials (RCTs) are necessary to shed light on the pathways connecting chronic subclinical inflammation/meta-inflammation with adverse COVID-19 outcomes and establish the ideal preventive and therapeutic approaches for patients with obesity.

The Role of Chronic Inflammation in the Development of Breast Cancer

Chronic inflammation contributes to the malignant transformation of several malignancies and is an important component of breast cancer. The role of chronic inflammation in the initiation and development of breast cancer from normal breast tissue, however, is unclear and needs to be clarified. A review of the literature was conducted to define the chronic inflammatory processes in normal breast tissue at risk for breast cancer and in breast cancer, including the role of lymphocyte and macrophage infiltrates, chronic active adipocytes and fibroblasts, and processes that may promote chronic inflammation including the microbiome and factors related to genomic abnormalities and cellular injury. The findings indicate that in healthy normal breast tissue there is systemic evidence to suggest inflammatory changes are present and associated with breast cancer risk, and adipocytes and crown-like structures in normal breast tissue may be associated with chronic inflammatory changes. The microbiome, genomic abnormalities, and cellular changes are present in healthy normal breast tissue, with the potential to elicit inflammatory changes, while infiltrating lymphocytes are uncommon in these tissues. Chronic inflammatory changes occur prominently in breast cancer tissues, with important contributions from tumor-infiltrating lymphocytes and tumor-associated macrophages, cancer-associated adipocytes and crown-like structures, and cancer-associated fibroblasts, while the microbiome and DNA damage may serve to promote inflammatory events. Together, these findings suggest that chronic inflammation may play a role in influencing the initiation, development and conduct of breast cancer, although several chronic inflammatory processes in breast tissue may occur later in breast carcinogenesis.

Is resistin the master link between inflammation and inflammation-related chronic diseases?

Resistin has been firstly discovered in mice and was identified as an adipose tissue-secreted hormone or adipokine linking obesity and insulin resistance. In humans, resistin has been characterized as a hormone expressed and secreted by Immune cells especially by macrophages, and was linked to many inflammatory responses including inflammation of adipose tissue due to macrophages' infiltration. Human and mouse resistin display sequence and structural similarities and also dissimilarities that could explain their different expression pattern. In mice, strong pieces of evidence clearly associated high resistin plasma levels to obesity and insulin resistance suggesting that resistin could play an important role in the onset and progression of obesity and insulin resistance via resistin-induced inflammation. In humans, the link between resistin and obesity/insulin resistance is still a matter of debate and needs more epidemiological studies. Also, resistin has been linked to other chronic diseases such as cardiovascular diseases and cancers where resistin has been proposed in many studies as a biological marker.

Resistin: A journey from metabolism to cancer

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Resistin levels have been associated with several pathological disorders such as metabolic disorders, cancers etc.

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Resistin exists in three isoforms namely RELM-α, β and γ.

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High resistin level activates inflammatory pathways, promotes metabolic disorders and is associated with carcinogenesis.

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Increase in the resistin level impairs the therapeutic response by inducing stemness or resistance, in cancer cells.

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Conventional drugs which alter resistin level could have therapeutic implications in several pathological disorders.

Resistin, a small secretory molecule, has been implicated to play an important role in the development of insulin resistance under obese condition. For the past few decades, it has been linked to various cellular and metabolic functions. It has been associated with diseases like metabolic disorders, cardiovascular diseases and cancers. Numerous clinical studies have indicated an increased serum resistin level in pathological disorders which have been reported to increase mortality rate in comparison to low resistin expressing subjects. Various molecular studies suggest resistin plays a pivotal role in proliferation, metastasis, angiogenesis, inflammation as well as in regulating metabolism in cancer cells. Therefore, understanding the role of resistin and elucidating its’ associated molecular mechanism will give a better insight into the management of these disorders. In this article, we summarize the diverse roles of resistin in pathological disorders based on the available literature, clinicopathological data, and a compiled study from various databases. The article mainly provides comprehensive information of its role as a target in different treatment modalities in pre as well as post-clinical studies.

The Effect of Antioxidant and Anti-Inflammatory Capacity of Diet on Psoriasis and Psoriatic Arthritis Phenotype: Nutrition as Therapeutic Tool?

Chronic inflammation and increased oxidative stress are contributing factors to many non-communicable diseases. A growing body of evidence indicates that dietary nutrients can activate the immune system and may lead to the overproduction of pro-inflammatory cytokines. Fatty acids as macronutrients are key players for immunomodulation, with n-3 polyunsaturated fatty acids having the most beneficial effect, while polyphenols and carotenoids seem to be the most promising antioxidants. Psoriasis is a chronic, immune-mediated inflammatory disease with multifactorial etiology. Obesity is a major risk factor for psoriasis, which leads to worse clinical outcomes. Weight loss interventions and, generally, dietary regimens such as gluten-free and Mediterranean diet or supplement use may potentially improve psoriasis’ natural course and response to therapy. However, data about more sophisticated nutritional patterns, such as ketogenic, very low-carb or specific macro- and micro-nutrient substitution, are scarce. This review aims to present the effect of strictly structured dietary nutrients, that are known to affect glucose/lipid metabolism and insulin responses, on chronic inflammation and immunity, and to discuss the utility of nutritional regimens as possible therapeutic tools for psoriasis and psoriatic arthritis.

Resistin is co-secreted with adiponectin in white mouse adipocytes

In the current work we have investigated the cellular and molecular regulation of resistin secretion in cultured and primary mouse adipocytes. Resistin is an adipose tissue hormone proposed to contribute to metabolic disease. In rodents, resistin is secreted from white adipocytes whereas it is in humans synthesised and released from other cell types within white adipose tissue. The metabolic importance of resistin has been studied in both mouse and man, but the regulation of its release remains poorly investigated. Here we define that, in mouse adipocytes, resistin secretion is triggered by an intracellular elevation of cAMP and/or Ca²⁺. Resistin release is stimulated via activation of beta 3 adrenergic receptors (β₃ARs) and the downstream signalling protein exchange protein activated by cAMP (Epac). The secretion of resistin is markedly abrogated in adipocytes isolated from obese and diabetic mice. Immunocytochemical staining demonstrates a significant overlap between signals for resistin and the adipocyte hormone adiponectin. Our data propose that resistin and adiponectin are contained within the same vesicles in mouse adipocytes and that the two hormones are co-secreted in response to the same exocytosis-triggering signals.

Significance of Some Non-Invasive Biomarkers in the Early Diagnosis and Staging of Egyptian Breast Cancer Patients

Introduction:

Breast cancer is one of the most relevant malignancies among women. Early diagnosis and accurate staging of breast cancer is important for the selection of an appropriate therapeutic strategy and achieving a better outcome.

Aim:

This study aimed to explore the significance of some non-invasive biomarkers in the early diagnosis and staging of Egyptian breast cancer patients.

Subjects and Methods:

A total of 135 female patients with physically and pathologically confirmed breast cancer and 40 unrelated controls as well as 40 patients with benign breast mass were enrolled in this study. The malignant breast cancer group was further divided into four groups according to tumor size. Serum levels of carcinoembryonic antigen-related cell adhesion molecule-1 (CEACAM1), resistin and visfatin were determined by enzyme immunoassay.

Results:

Elevated levels of CEACAM1, resistin and visfatin were observed in breast cancer patients when compared with normal control and benign groups. The cutoff values, sensitivities and specificities of these biomarkers were appropriate for the discrimination of breast cancer from controls. Additionally, the serum levels of visfatin increased positively with tumor size and consequently with breast cancer stages.

Conclusion:

CEACAM1, resistin and visfatin are valuable in early diagnosis of breast cancer, with visfatin being preferentially used in staging.

Autoantibody Production in Obesity: Is There Evidence for a Link Between Obesity and Autoimmunity?

PURPOSE OF REVIEW

During the last decades, obesity and autoimmune disorders have shown a parallel significant rise in industrialized countries. This review aims at providing a comprehensive update of the relationship between the adipose tissue in obesity and autoimmune disorders, highlighting the underlying mechanisms with a particular emphasis on adipokines and pro-inflammatory cytokines, the impaired B cell activity, and the production of natural and pathogenic autoantibody repertoire in the context of obesity.

RECENT FINDINGS

Obesity is related to a higher risk of rheumatoid arthritis, psoriasis and psoriatic arthritis, multiple sclerosis, and Hashimoto's thyroiditis, while it may promote inflammatory bowel disorders and type 1 diabetes mellitus. Interestingly, subjects with obesity present more severe forms of these autoimmune disorders as well as decreased therapeutic response. Both obesity and autoimmune disorders present elevated levels of leptin, resistin, and visfatin. Autoantibody production, a hallmark of autoimmune disorders, has been demonstrated in obese animal models and human subjects. Obesity results in deficiencies of the human self-tolerance mechanisms by promoting pro-inflammatory processes, reducing Bregs as well as Tregs, and the latter resulting in increased Th17 and Th1 cells, creating the perfect milieu for the development of autoimmune disorders. More mechanistic, animal, and clinical studies are required to delineate the exact mechanisms underlying auto-reactivity in obesity as well as the adipose-immune crosstalk for potential successful therapeutic strategies.

Deciphering the Association Between Psoriasis and Obesity: Current Evidence and Treatment Considerations

PURPOSE OF REVIEW

Obesity and psoriasis represent chronic inflammatory states that are interconnected in a vicious cycle, sharing also a degree of synergy. In this review, we aim to decipher the various lines of evidence supporting the bidirectional association between psoriasis and obesity highlighting their pathophysiologic connections as well as we attempt to strategize a therapeutic holistic approach for obese psoriatic patients.

RECENT FINDINGS

Recent meta-analyses have shown that (1) genetically higher BMI increased the odds of psoriasis occurrence; (2) obesity is associated with higher incidence and prevalence of psoriasis as well as psoriasis severity; (3) obesity is associated with lower efficacy to anti-TNF agents and may predict biologic treatment discontinuation; and (4) weight loss through diet and physical exercise may improve pre-existing psoriasis and prevent from de novo psoriasis. Methotrexate, acitretin, and cyclosporine could worsen hypertension, liver steatosis, and dyslipidemia. Since infliximab and ustekinumab are weight adjusted, they may be ideal drugs to treat obese psoriatic patients. IL-17 inhibitors are very effective independently from body weight; however, they tend to present better clearance rates in normal weight patients. There is a paucity on weight data regarding the efficacious IL-23 inhibitors. Apremilast may induce weight loss as an adverse effect presenting also some beneficial metabolic actions. Finally, simvastatin and some antidiabetic drugs could decrease psoriasis severity. More mechanistic, observational studies and well-conducted RCTs are necessary to decipher the enigmatic link between psoriasis and obesity, and to provide evidence-based specific guidelines for the screening and management of obese psoriatic patients.

Resistin: An inflammatory cytokine with multi-faceted roles in cancer

Systemic and organ-confined inflammation has been associated with cancer development and progression. Resistin, initially described as an adipocyte-derived cytokine in mice, is mostly expressed by the macrophages in humans. It has potent pro-inflammatory properties, and its elevated serum levels are detected in cancer patients. Aberrant expression of resistin receptors is also reported in several malignancies and associated with aggressive clinicopathological features. Several lines of evidence demonstrate that resistin, acting through its different receptors, promotes tumor growth, metastasis, and chemoresistance by influencing a variety of cellular phenotypes as well as by modulating the tumor microenvironment. Racially disparate expression of resistin has also attracted much interest, considering prevalent cancer health disparities. This review discusses the aberrant expression of resistin and its receptors, its diverse downstream signaling and impact on tumor growth, metastasis, angiogenesis, and therapy resistance to support its clinical exploitation in biomarker and therapeutic development.

The Role of Adipokines in Breast Cancer: Current Evidence and Perspectives

PURPOSE

The current review shows evidence for the role of adipokines in breast cancer (BC) pathogenesis summarizing the mechanisms underlying the association between adipokines and breast malignancy. Special emphasis is given also on intriguing insights into the relationship between obesity and BC as well as on the role of novel adipokines in BC development.

RECENT FINDINGS

Recent evidence has underscored the role of the triad of obesity, insulin resistance, and adipokines in postmenopausal BC. Adipokines exert independent and joint effects on activation of major intracellular signal networks implicated in BC cell proliferation, growth, survival, invasion, and metastasis, particularly in the context of obesity, considered a systemic endocrine dysfunction characterized by chronic inflammation. To date, more than 10 adipokines have been linked to BC, and this catalog is continuously increasing. The majority of circulating adipokines, such as leptin, resistin, visfatin, apelin, lipocalin 2, osteopontin, and oncostatin M, is elevated in BC, while some adipokines such as adiponectin and irisin (adipo-myokine) are generally decreased in BC and considered protective against breast carcinogenesis. Further evidence from basic and translational research is necessary to delineate the ontological role of adipokines and their interplay in BC pathogenesis. More large-scale clinical and longitudinal studies are awaited to assess their clinical utility in BC prognosis and follow-up. Finally, novel more effective and safer adipokine-centered therapeutic strategies could pave the way for targeted oncotherapy.

The Role of Adipose Tissue and Adipokines in Sepsis: Inflammatory and Metabolic Considerations, and the Obesity Paradox

PURPOSE

Sepsis has become a global health problem with rising incidence and high mortality, creating a substantial social and economic burden. Early diagnosis and treatment can improve outcome, but reliable sepsis biomarkers are lacking. This review summarizes current evidence of the pathophysiological mechanisms linking adipose tissue to sepsis and presents experimental and clinical data on adipokines and sepsis along with important insights into the obesity paradox in sepsis survival.

RECENT FINDINGS

Sepsis is characterized by significant alterations in circulating cytokines and adipokines, biologically active molecules produced by the adipose tissue, being implicated in metabolic and inflammatory processes. Although data are inconclusive regarding classic adipokines such as leptin and adiponectin, recent evidence have highlighted the striking elevation of resistin and visfatin in critical illness and sepsis as well as their association with sepsis severity and outcomes. Given that inflammatory and metabolic pathways are involved in sepsis, studying adipokines presents an attractive, innovative, and promising research field that may provide more powerful diagnostic and prognostic biomarkers as well as novel therapeutic targets, empowering the therapeutic armamentarium for sepsis management in order to improve survival.

Resistin induces breast cancer cells epithelial to mesenchymal transition (EMT) and stemness through both adenylyl cyclase-associated protein 1 (CAP1)-dependent and CAP1-independent mechanisms

Breast cancer incidence and metastasis in postmenopausal women are known to associate with obesity, but the molecular mechanisms behind this association are largely unknown. We investigated the effect of adipokine resistin on epithelial to mesenchymal transition (EMT) and stemness in breast cancer cells in vitro. Previous reports demonstrated that the inflammatory actions of resistin are mediated by the adenylyl cyclase-associated protein 1 (CAP1), which serves as its receptor. As a model for our study, we used MCF-7 and MDA-MB-231 breast cancer and MCF-10A breast epithelial cells. We showed that in MCF-7 cells resistin increases the migration of MCF-7 and MDA-MB-231 cells and induces the formation of cellular protrusions through reorganization of F-actin filaments. Resistin upregulated the expression of mesenchymal markers involved in EMT (SNAIL, SLUG, ZEB1, TWIST1, fibronectin, and vimentin), and downregulated those of epithelial markers (E-cadherin and claudin-1). Resistin also potentiated the nuclear translocation of SNAIL protein, indicating initiation of EMT reprogramming. We further induced EMT in non-carcinogenic breast epithelial MCF-10A cells demonstrating that the effects of resistin on EMT were not breast cancer cell specific. In order to assess whether resistin-induced EMT depends on CAP1, we used siRNA approach to silence CAP1 gene in MCF-7 cells. Results demonstrated that when CAP1 was silenced, the induction of SNAIL, ZEB1 and vimentin expression by resistin as well as SNAIL and ZEB1 nuclear translocation, were abolished. Additionally, CAP1 silencing resulted in a suppression of MCF-7 cells migration. We performed quantitative PCR array profiling the expression of 84 genes related to cancer stem cells (CSC), pluripotency and metastasis and selected a set of genes (ALDH1A1, ITGA4, LIN28B, SMO, KLF17, PTPRC, PROM1, SIRT1, and PECAM1) that were modulated by resistin. Further experiments demonstrated that the effect of resistin on the expression of some of these genes (PROM1, PTPRC, KLF17, SIRT1, and PECAM1) was also dependent on CAP1. Our results demonstrate that resistin promotes the metastatic potential of breast cancer cells by inducing EMT and stemness and some of these effects are mediated by CAP1.

Association among resistin, adenylate cyclase-associated protein 1 and high-density lipoprotein cholesterol in patients with colorectal cancer: a multi-marker approach, as a hallmark of innovative predictive, preventive, and personalized medicine

Background

Elevated concentrations of resistin have been reported in colorectal cancer (CRC), but its interactions with adenylate cyclase-associated protein 1 (CAP-1) are largely unexplored. We investigated resistin plasma concentration, peripheral blood mononuclear cells (PBMCs) resistin messenger ribonucleic acid (mRNA), and CAP-1 mRNA levels in CRC patients, as well as the impact of resistin gene polymorphism rs1862513 on the examined markers. We also explored associations of resistin with high-density lipoprotein cholesterol (HDL-C) and predictive potential of our parameters for CRC.

Methods

Eighty-six patients with CRC and 75 healthy adults were included. Commercial ELISA kit was used for obtaining resistin's concentrations, while polymerase chain reaction (PCR) method was applied for evaluation of resistin and CAP-1 mRNA levels and rs1862513 polymorphism.

Results

Plasma resistin and CAP-1 mRNA levels were higher in CRC patients (p < 0.001 and p < 0.05, respectively), while resistin mRNA levels were lower (p < 0.001). Negative association existed among plasma resistin and HDL-C concentrations (ρ = - 0.280; p < 0.05). A model including age, body-mass index, HDL-C, low-density lipoprotein cholesterol (LDL-C), and plasma resistin concentrations as independent predictors of CRC showed very good diagnostic accuracy (AUC = 0.898). We found no associations of rs1862513 with the examined markers.

Conclusions

Our study demonstrated increased plasma resistin and CAP-1 mRNA levels, implying their possible interaction in CRC. The association among plasma resistin and HDL-C might indicate that HDL-C is involved in alterations of resistin's secretion process. As a hallmark of personalized medicine, multi-marker approach in determination of resistin-related parameters might be useful for prediction and prevention of CRC development.

Association between obesity and biomarkers of inflammation and metabolism with cancer mortality in a prospective cohort study

OBJECTIVE

To investigate the association between biomarkers of inflammation and metabolic dysregulation and cancer mortality by obesity status.

METHODS

Data from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) cohort was used to examine the associations between baseline biomarkers of inflammation (IL-6, IL-8, IL-10, and CRP) and metabolism (adiponectin, resisting and lipoprotein (a)) with cancer mortality among 1822 participants cancer-free at baseline. Weighted Cox proportional hazard regression with the robust sandwich method was used to estimate the hazard ratios and 95% confidence intervals (CIs) adjusting for baseline covariates and stratified by BMI (normal, overweight/obese) given the significant interaction between biomarkers and BMI (p < 0.1).

RESULTS

During a mean follow-up of 8 years, there were statistically significant associations between cancer mortality and being in the highest vs. lowest tertile of IL-6 (HR: 5.3; 95% CI: 1.6, 17.8), CRP (HR: 3.4; 95% CI: 1.0, 11.2) and resistin (HR: 3.7; 95% CI: 1.2, 11.2) among participants with normal BMI. IL-6 was also associated with a 3-fold (HR: 3.5; 95% CI: 1.5, 8.1) increased risk of cancer mortality among participants with overweight/obesity; however, neither CRP nor resistin was significantly associated with cancer mortality in this group.

CONCLUSIONS

Higher baseline inflammatory and metabolic biomarkers were associated with significantly increased risk of cancer mortality after adjusting for baseline risk factors and the associations varied by BMI. Cancer patients may benefit from interventions that modulate inflammatory and metabolic biomarkers.

Circulating eNampt and resistin as a proinflammatory duet predicting independently mortality in critically ill patients with sepsis: A prospective observational study

BACKGROUND

The adipocytokines eNampt and resistin are involved in the regulation of inflammation exerting pro-inflammatory actions. Our aim was to jointly investigate whether circulating eNampt and resistin, and their kinetics predict 28-day mortality of sepsis.

METHODS

In a prospective study, serum eNampt and resistin were determined in 102 critically ill patients fulfilling the diagnostic criteria of SEPSIS-3, at enrollment and one week after, and in 102 healthy controls matched on age, gender and month of diagnosis.

RESULTS

Serum eNampt and resistin were significantly higher in septic patients than controls (p < 0.001), and higher in septic shock compared to sepsis (p < 0.001). Both eNampt and resistin decreased significantly during the first week of sepsis (p < 0.001). However, patients with septic shock presented a sustained elevation of eNampt and resistin compared to patients with sepsis. Both adipocytokines were positively correlated with sepsis severity scores and lactate. Baseline eNampt was a better discriminator of sepsis and septic shock compared to C-reactive protein and procalcitonin. Serum eNampt and resistin were higher in nonsurvivors than in survivors during the first week of sepsis. Prolonged and sustained elevation of both eNampt and resistin, as reflected by a lower percentage change from their baseline values, was independently associated with 28-day mortality (HR: 0.05, 95% C.I. 0.01-0.28, p = 0.001; HR: 0.19, 95% C.I. 0.07-0.50, p = 0.001, respectively), after adjustment for significant clinical and laboratory biomarkers.

CONCLUSION

Circulating eNampt and resistin, and their kinetics may represent useful diagnostic and prognostic biomarkers in critically ill septic patients. More prospective studies are needed to elucidate their ontological and pathophysiological role in sepsis.

Obesity and cancer risk: Emerging biological mechanisms and perspectives

Continuously rising trends in obesity-related malignancies render this disease spectrum a public health priority. Worldwide, the burden of cancer attributable to obesity, expressed as population attributable fraction, is 11.9% in men and 13.1% in women. There is convincing evidence that excess body weight is associated with an increased risk for cancer of at least 13 anatomic sites, including endometrial, esophageal, renal and pancreatic adenocarcinomas; hepatocellular carcinoma; gastric cardia cancer; meningioma; multiple myeloma; colorectal, postmenopausal breast, ovarian, gallbladder and thyroid cancers. We first synopsize current epidemiologic evidence; the obesity paradox in cancer risk and mortality; the role of weight gain and weight loss in the modulation of cancer risk; reliable somatometric indicators for obesity and cancer research; and gender differences in obesity related cancers. We critically summarize emerging biological mechanisms linking obesity to cancer encompassing insulin resistance and abnormalities of the IGF-I system and signaling; sex hormones biosynthesis and pathway; subclinical chronic low-grade inflammation and oxidative stress; alterations in adipokine pathophysiology; factors deriving from ectopic fat deposition; microenvironment and cellular perturbations including vascular perturbations, epithelial-mesenchymal transition, endoplasmic reticulum stress and migrating adipose progenitor cells; disruption of circadian rhythms; dietary nutrients; factors with potential significance such as the altered intestinal microbiome; and mechanic factors in obesity and cancer. Future perspectives regarding prevention, diagnosis and therapeutics are discussed. The aim of this review is to investigate how the interplay of these main potential mechanisms and risk factors, exerts their effects on target tissues provoking them to acquire a cancerous phenotype.

Classic and Novel Adipocytokines at the Intersection of Obesity and Cancer: Diagnostic and Therapeutic Strategies

PURPOSE OF REVIEW

In this review, we investigate the role of classic and novel adipocytokines in cancer pathogenesis synopsizing the mechanisms underlying the association between adipocytokines and malignancy. Special emphasis is given on novel adipocytokines as new evidence is emerging regarding their entanglement in neoplastic development.

RECENT FINDINGS

Recent data have emphasized the role of the triad of overweight/obesity, insulin resistance and adipocytokines in cancer. In the setting of obesity, classic and novel adipocytokines present independent and joint effects on activation of major intracellular signaling pathways implicated in cell proliferation, expansion, survival, adhesion, invasion, and metastasis. Until now, more than 15 adipocytokines have been associated with cancer, and this list continues to expand. While the plethora of circulating pro-inflammatory adipocytokines, such as leptin, resistin, extracellular nicotinamide phosphoribosyl transferase, and chemerin are elevated in malignancies, some adipocytokines such as adiponectin and omentin-1 are generally decreased in cancers and are considered protective against carcinogenesis. Elucidating the intertwining of inflammation, cellular bioenergetics, and adiposopathy is significant for the development of preventive, diagnostic, and therapeutic strategies against cancer. Novel more effective and safe adipocytokine-centered therapeutic interventions may pave the way for targeted oncotherapy.

Increased resistin suggests poor prognosis and promotes development of lung adenocarcinoma

Resistin is considered to be a risk factor for several types of cancer, but its functions are controversial and not well studied in lung cancer. The present study is aimed to investigate the expression of resistin in lung adenocarcinoma tissues, in order to evaluate its association with the clinicopathological characteristics of cancer patients and to investigate the effects of resistin in lung adenocarcinoma cells. A total of 70 pairs of lung adenocarcinoma tissues and normal tissues were collected and immunohistochemistry was performed to examine resistin expression. Resistin overexpressed cells were established by plasmid transfection in A549 or H1975 cells. Alterations in cell proliferation, apoptosis, migration and invasion were analyzed in vitro. A nude mouse tumorigenicity assay was used to test the effect of resistin in vivo. High expression of resistin was predominantly observed in lung adenocarcinoma tissues but not in adjacent normal lung tissues. Resistin expression was significantly associated with increased tumor size, clinical stage as well as lymph node metastasis while negatively associated with progression-free survival (PFS) and overall survival (OS). Expression of resistin was an independent risk factor for PFS and OS. Overexpression of resistin promoted significant proliferation, migration and invasion, while also inhibited apoptosis in vitro. Resistin also promoted tumor formation in nude mice. The potential molecular mechanism was also investigated by in vitro experiments. In conclusion, the present study revealed that a high level of resistin expression in lung adenocarcinoma tissues is associated with poor clinicopathological status and survival. Resistin, which promotes the development of lung adenocarcinoma in vitro and in vivo may be a novel target for lung adenocarcinoma.

Novel oncogenic and chemoresistance-inducing functions of resistin in ovarian cancer cells require miRNAs-mediated induction of epithelial-to-mesenchymal transition

Resistin plays a role in the growth, proliferation, angiogenesis, metastasis and therapeutic resistance in different cancers. However, such effects of resistin have never been evaluated in ovarian cancer, a deadly gynecological malignancy. We observed a significant induction of ovarian cancer cells' growth, invasion and cisplatin resistance, and established a mechanism of resistin action that included induction of EMT and stemness, as evidenced by down-regulated epithelial marker e-cadherin and up-regulated mesenchymal markers vimentin/ ZEB1 and stemness markers sox2, oct4 and nanog. The mechanism also included suppression of tumor suppressor miRNAs, let-7a, miR-200c and miR-186. Over-expression of these miRNAs significantly reversed the resistin-mediated effects on invasion and chemoresistance. We further validated our results in vivo where resistin administration significantly enhanced tumor growth in mice. Our results provide first evidence for such oncogenic effects of resistin in ovarian cancer models and a rationale for future studies to further understand the mechanistic role of resistin in ovarian cancer invasiveness, metastasis and therapy resistance.

The role of extracellular and intracellular Nicotinamide phosphoribosyl-transferase in cancer: Diagnostic and therapeutic perspectives and challenges

Nicotinamide phosphoribosyl-transferase (Nampt) or pre-B cell colony-enhancing factor or visfatin represents a pleiotropic molecule acting as an enzyme, a cytokine and a growth factor. Intracellular Nampt plays an important role in cellular bioenergetics and metabolism, particularly NAD biosynthesis. NAD biosynthesis is critical in DNA repair, oncogenic signal transduction, transcription, genomic integrity and apoptosis. Although its insulin-mimetic function remains a controversial issue, extracellular Nampt presents proliferative, anti-apoptotic, pro-inflammatory, pro-angiogenic and metastatic properties. Nampt is upregulated in many malignancies, including obesity-associated cancers, and is associated with worse prognosis. Serum Nampt may be a potential diagnostic and prognostic biomarker in cancer. Pharmacologic agents that neutralize Nampt or medications that decrease Nampt levels or downregulate signaling pathways downstream of Nampt may prove to be useful anti-cancer treatments. In particular, Nampt inhibitors as monotherapy or in combination therapy have displayed anti-cancer activity in vivo and in vitro. The aim of this review is to explore the role of Nampt in cancer pathophysiology as well as to synopsize the mechanisms underlying the association between extracellular and intracellular Nampt, and malignancy. Exploring the interplay of cellular bioenergetics, inflammation and adiposopathy is expected to be of importance in the development of preventive and therapeutic strategies against cancer.

Molecular aspects of diabetes mellitus: Resistin, microRNA, and exosome

Diabetes mellitus (DM) is known as one of important common endocrine disorders which could due to deregulation of a variety of cellular and molecular pathways. A large numbers studies indicated that various pathogenesis events including mutation, serin phosphorylation, and increasing/decreasing expression of many genes could contribute to initiation and progression of DM. Insulin resistance is one of important factors which could play critical roles in DM pathogenesis. It has been showed that insulin resistance via targeting a sequence of cellular and molecular pathways (eg, PI3 kinases, PPARγ co-activator-1, microRNAs, serine/threonine kinase Akt, and serin phosphorylation) could induce DM. Among of various factors involved in DM pathogenesis, microRNAs, and exosomes have been emerged as effective factors in initiation and progression of DM. A variety of studies indicated that deregulation of these molecules could change behavior of various types of cells and contribute to progression of DM. Resistin is other main factor which is known as signal molecule involved in insulin resistance. Multiple lines evidence indicated that resistin exerts its effects via affecting on glucose metabolism, inhibition of fatty acid uptake and metabolism with affecting on a variety of targets such as CD36, fatty acid transport protein 1, Acetyl-CoA carboxylase, and AMP-activated protein kinase. Here, we summarized various molecular aspects are associated with DM particularly the molecular pathways involved in insulin resistance and resistin in DM. Moreover, we highlighted exosomes and microRNAs as effective players in initiation and progression of DM.

Effect of plant-based diets on obesity-related inflammatory profiles: a systematic review and meta-analysis of intervention trials

Plant-based dietary interventions have been proposed to reduce obesity induced chronic low-grade inflammation and hence prevent chronic disease risk; however, human evidence remains unclear. This systematic review and meta-analysis of intervention trials aimed to assess the effect of plant-based diets on obesity-related inflammatory biomarker profiles. Medline, EMBASE and Cochrane Central Register of Controlled Trials (CENTRAL) were searched for articles published until January 2016 and mean differences in biomarkers of inflammatory status were assessed for: C-reactive protein (CRP), interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-ɑ), soluble intercellular adhesion molecule 1 (sICAM), leptin, adiponectin and resistin. Of initially identified 2,583 publications, 29 met the meta-analysis inclusion criteria [a total of 2,689 participants]. Consumption of plant-based diets was associated with a reduction in the mean concentrations of the following biomarkers: CRP [effect size, -0.55 mg/l, 95% confidence intervals (CI): -0.78; -0.32, I²  = 94.4%], IL-6 [effect size, -0.25 ng/l, 95% CI: -0.56; 0.06, I²  = 74%], and, to some degree, sICAM (-25.07 ng/ml [95% CI: -52.32; 2.17, I²  = 93.2%]). No substantial effects were revealed for TNF-ɑ, resistin, adiponectin and leptin. Plant-based diets are associated with an improvement in obesity-related inflammatory profiles and could provide means for therapy and prevention of chronic disease risk.

Circulating resistin levels and obesity-related cancer risk: A meta-analysis

Resistin levels have been reported to be abnormal in obesity-related cancer patients with epidemiological studies yielding inconsistent results. Therefore, a meta-analysis was performed to assess the association between blood resistin levels and obesity-related cancer risk. A total of 13 studies were included for pooling ORs analysis. High resistin levels were found in cancer patients (OR= 1.20, 95% CI= 1.10-1.30). After excluding one study primarily contributing to between-study heterogeneity, the association between resistin levels and cancer risk was still significant (OR=1.18, 95% CI = 1.09-1.28). Stratification analysis found resistin levels were not associated with cancer risk in prospective studies. Meta-regression analysis identified factors such as geographic area, detection assay, or study design as confounders to between-study variance. The result of 18 studies of pooling measures on SMD analysis was that high resistin levels were associated with increased cancer risk (SMD = 0.94, 95% CI = 0.63-1.25), but not in the pooling SMD analysis of prospective studies. Except for the studies identified as major contributors to heterogeneity by Galbraith plot, resistin levels were still higher in cancer patients (SMD = 0.75, 95% CI = 0.63-0.87) in retrospective studies. Meta-regression analysis found factors, such as geographic area, BMI-match, size, and quality score, could account for 66.7% between-study variance in pooling SMD analysis of retrospective studies. Publication bias was not found in pooling ORs analysis. Our findings indicated high resistin levels were associated with increased obesity-related cancer risk. However, it may not be a predictor.

Hyperresistinemia and metabolic dysregulation: a risky crosstalk in obese breast cancer

Breast cancer is the most common malignancy among women worldwide. There is extensive literature on the relationship between body weight and breast cancer risk but some doubts still remain about the role of adipokines per se, the role of insulin and glucose regardless of obesity, as well as the crosstalk between these players. Thus, in this study, we intend to determine the relation between body mass index (BMI), glycaemia, insulinemia, insulin-resistance, blood adipokine levels and tumour characteristics in a Portuguese group of pre- and postmenopausal overweight/obese women with breast cancer. We evaluated clinical and biochemical data in 154 participants, divided in 4 groups: (1) control with BMI <25 kg/m(2), n = 29 (CT); (2) control with BMI >25 kg/m(2), n = 48 (CTOb); (3) breast cancer with BMI <25 kg/m(2), n = 30 (BC); and (4) breast cancer with BMI >25 kg/m(2), n = 47 (BCOb). In women with breast cancer, we also performed tumour characterization. We found that BCOb present increased fasting blood glucose, insulin, resistin and monocyte chemoattractant protein 1, insulin resistance and more aggressive tumours. Notably, this profile is not correlated with BMI, proposing the involvement of other processes than adiposity. Altogether, our results suggest that glucose dysmetabolism, insulin resistance and changes in adipokine secretion, in particular resistin, may be involved in the development and progression of breast cancer in overweight/obese pre- and postmenopausal women.

Elevated Resistin Gene Expression in African American Estrogen and Progesterone Receptor Negative Breast Cancer

INTRODUCTION

African American (AA) women diagnosed with breast cancer are more likely to have aggressive subtypes. Investigating differentially expressed genes between patient populations may help explain racial health disparities. Resistin, one such gene, is linked to inflammation, obesity, and breast cancer risk. Previous studies indicated that resistin expression is higher in serum and tissue of AA breast cancer patients compared to Caucasian American (CA) patients. However, resistin expression levels have not been compared between AA and CA patients in a stage- and subtype-specific context. Breast cancer prognosis and treatments vary by subtype. This work investigates differential resistin gene expression in human breast cancer tissues of specific stages, receptor subtypes, and menopause statuses in AA and CA women.

METHODS

Differential gene expression analysis was performed using human breast cancer gene expression data from The Cancer Genome Atlas. We performed inter-race resistin gene expression level comparisons looking at receptor status and stage-specific data between AA and CA samples. DESeq was run to test for differentially expressed resistin values.

RESULTS

Resistin RNA was higher in AA women overall, with highest values in receptor negative subtypes. Estrogen-, progesterone-, and human epidermal growth factor receptor 2- negative groups showed statistically significant elevated resistin levels in Stage I and II AA women compared to CA women. In inter-racial comparisons, AA women had significantly higher levels of resistin regardless of menopause status. In whole population comparisons, resistin expression was higher among Stage I and III estrogen receptor negative cases. In comparisons of molecular subtypes, resistin levels were significant higher in triple negative than in luminal A breast cancer.

CONCLUSION

Resistin gene expression levels were significantly higher in receptor negative subtypes, especially estrogen receptor negative cases in AA women. Resistin may serve as an early breast cancer biomarker and possible therapeutic target for AA breast cancer.

A role for novel adipose tissue-secreted factors in obesity-related carcinogenesis

Obesity, a pandemic disease, is caused by an excessive accumulation of fat that can have detrimental effects on health. Adipose tissue plays a very important endocrine role, secreting different molecules that affect body physiology. In obesity, this function is altered, leading to a dysfunctional production of several factors, known as adipocytokines. This process has been linked to various comorbidities associated with obesity, such as carcinogenesis. In fact, several classical adipocytokines with increased levels in obesity have been demonstrated to exert a pro-carcinogenic role, including leptin, TNF-α, IL-6 and resistin, whereas others like adiponectin, with decreased levels in obesity, might have an anti-carcinogenic function. In this expanding field, new proteomic techniques and approaches have allowed the identification of novel adipocytokines, a number of which exhibit an altered production in obesity and type 2 diabetes and thus are related to adiposity. Many of these novel adipocytokines have also been identified in various tumour types, such as that of the breast, liver or endometrium, thereby increasing the list of potential contributors to carcinogenesis. This review is focused on the regulation of these novel adipocytokines by obesity, including apelin, endotrophin, FABP4, lipocalin 2, omentin-1, visfatin, chemerin, ANGPTL2 or osteopontin, emphasizing its involvement in tumorigenesis.

Serum Resistin Levels May Contribute to an Increased Risk of Acute Cerebral Infarction

The objective of this study was to investigate the association between serum resistin levels and acute cerebral infarction (ACI). PubMed, SpringerLink, Wiley, EBSCO, Ovid, Web of Science, Wanfang, China National Knowledge Infrastructure, and VIP databases (last updated search in October 2014) were exhaustively searched, and data from the eligible studies were extracted and analyzed to assess the association between serum resistin levels and ACI. STATA software (version 12.0, Stata Corporation, College Station, TX, USA) was utilized for data analysis. Ten studies including 1829 ACI patients and 1557 healthy controls were eligible for inclusion in the meta-analysis. Our major result revealed that ACI patients exhibited higher serum resistin levels compared with healthy controls. Asubgroup analysis based on ethnicity showed a significant association between serum resistin levels and ACI in Asians, but surprisingly not in Caucasians. The results of our meta-analysis suggest that serum resistin levels are associated with an increased risk of ACI.

Concentrations of adipokines in children before and after hematopoietic stem cell transplantation

Adipokines have multiple effects, including regulation of glucose metabolism, cell proliferation, inflammation, and angiogenesis. The aim of the study was to determine plasma concentrations of adiponectin, apelin, leptin, and resistin as well as soluble leptin receptor in pediatric hematopoietic stem cell transplantation (HSCT). The expression of genes encoding the studied peptides was measured using microarray technique. Plasma concentrations of tested peptides were measured before and after oral glucose tolerance test in children treated with HSCT (n = 38) and in healthy controls (n = 26). The peptides were measured before HSCT (pre-HSCT group; n = 38) and after a median of 6 months after HSCT (post-HSCT group; n = 27 of 38 children treated with HSCT). In addition, measurements of fasting plasma glucose, insulin, lipids, and high-sensitivity C-reactive protein (hsCRP) were performed. In both HSCT groups, atherogenic lipid profile, low-grade systemic inflammation was observed. Leptin, adiponectin, and resistin also appear to be good markers of disease burden and low-grade systemic inflammation. Adipokines may be good markers of disease burden and may influence metabolic complications of HSCT. Future studies on larger groups of patients will explain if changes of the concentrations of leptin, adiponectin, and apelin observed in our study and confirmed by expression levels influence engraftment and reconstitution of cell lines.

Resistin, a fat-derived secretory factor, promotes metastasis of MDA-MB-231 human breast cancer cells through ERM activation

Resistin, an adipocyte-secreted factor, is known to be elevated in breast cancer patients. However, the molecular mechanism by which resistin acts is not fully understood. The aim of this study was to investigate whether resistin could stimulate invasion and migration of breast cancer cells. Here, we report that resistin stimulated invasion and migration of breast cancer cells as well as phosphorylation of c-Src. Inhibition of c-Src blocked resistin-induced breast cancer cell invasion. Resistin increased intracellular calcium concentration, and chelation of intracellular calcium blocked resistin-mediated activation of Src. Resistin also induced phosphorylation of protein phosphatase 2A (PP2A). Inhibition of c-Src blocked resistin-mediated PP2A phosphorylation. In addition, resistin increased phosphorylation of PKCα. Inhibition of PP2A enhanced resistin-induced PKCα phosphorylation, demonstrating that PP2A activity is critical for PKCα phosphorylation. Resistin also increased phosphorylation of ezrin, radixin, and moesin (ERM). Additionally, ezrin interacted with PKCα, and resistin promoted co-localization of ezrin and PKCα. Either inhibition of c-Src and PKCα or knock-down of ezrin blocked resistin-induced breast cancer cells invasion. Moreover, resistin increased expression of vimentin, a key molecule for cancer cell invasion. Knock-down of ezrin abrogated resistin-induced vimentin expression. These results suggest that resistin play as a critical regulator of breast cancer metastasis.

Evaluation of diagnostic and predictive value of serum adipokines: Leptin, resistin and visfatin in postmenopausal breast cancer

Obesity is a well-known risk factor for cancer. The associations of obesity with postmenopausal breast cancer (PBC) have been previously proven in clinical studies. The mechanisms underlying these associations remain unexplained completely, however, adipose tissue as an endocrine organ producing adipokines may interfere with cancer development. The aim of this study is to investigate the diagnostic and predictive value of serum levels of leptin, resistin and visfatin with inflammatory and tumour markers in relation to anthropometrics, clinicopathological features of PBC. This study included 298 postmenopausal Saudi females categorised into three groups. One hundred and ten BC patients with age matched, 89 healthy control (HC) and 99 females with benign breast lesion (BBL). For all subjects CA15-3, hsCRP, resistin, visfatin and leptin were measured by ELISA. Serum levels of leptin, resistin and visfatin were significantly higher in BC compared to BBL and HC groups (p<0.05). Their levels were also significantly higher in advanced TNM stage, tumour size, LN invasion, histological grade and negative ER or PR cases. The most significant predictor of leptin level was ER (p<0.05). While for resistin and visfatin level the most significant independent predictor was LN invasion. ROC analysis for serum leptin revealed AUC=0.795; 95% CI, 0.724-0.866. Resistin showed AUC=0.875; 95% CI, 0.821-0.928. Meanwhile, visfatin greater than 12.2ng/mL demonstrated a sensitivity and specificity of 97.6% and 92.6%, respectively and AUC=0.724; 95% CI, 0.643-0.804. In conclusion serum leptin, resistin, and visfatin levels could be considered of potential diagnostic value for PBC and they would be independent predictors of LN invasion and ER negative PBC cases.

Obesity and cancer phenotype: Is angiogenesis a missed link?

Obesity remains nowadays one of the main threats to human health, being a problem of worldwide proportions. It is characterized by augmented storage of fatty acids in an enlarged adipose tissue. This process is possible thanks to a rich capillary network, supported by a mechanism that has also a crucial role on cancer: angiogenesis. Given that several studies point obesity as a risk factor for cancer development, angiogenesis may be approached as the missed link between these two pathologies. Understanding the different pathways behind angiogenesis becomes essential to break this link by developing new anti-angiogenic therapies or improving the actual ones. In the first phase, this paper will focus the structural and cellular changes that adipose tissue suffers in obesity. Then, the main pro-angiogenic players will be reviewed, taking into account the pathways that explain their putative role in obesity-cancer link. Finally, the clinical implications of the presented mechanisms will also be regarded, being the main focus on the anti-angiogenic therapies.

Evolution of the Vertebrate Resistin Gene Family

Resistin (encoded by Retn) was previously identified in rodents as a hormone associated with diabetes; however human resistin is instead linked to inflammation. Resistin is a member of a small gene family that includes the resistin-like peptides (encoded by Retnl genes) in mammals. Genomic searches of available genome sequences of diverse vertebrates and phylogenetic analyses were conducted to determine the size and origin of the resistin-like gene family. Genes encoding peptides similar to resistin were found in Mammalia, Sauria, Amphibia, and Actinistia (coelacanth, a lobe-finned fish), but not in Aves or fish from Actinopterygii, Chondrichthyes, or Agnatha. Retnl originated by duplication and transposition from Retn on the early mammalian lineage after divergence of the platypus, but before the placental and marsupial mammal divergence. The resistin-like gene family illustrates an instance where the locus of origin of duplicated genes can be identified, with Retn continuing to reside at this location. Mammalian species typically have a single copy Retn gene, but are much more variable in their numbers of Retnl genes, ranging from 0 to 9. Since Retn is located at the locus of origin, thus likely retained the ancestral expression pattern, largely maintained its copy number, and did not display accelerated evolution, we suggest that it is more likely to have maintained an ancestral function, while Retnl, which transposed to a new location, displays accelerated evolution, and shows greater variability in gene number, including gene loss, likely evolved new, but potentially lineage-specific, functions.

Resistin and interleukin-6 exhibit racially-disparate expression in breast cancer patients, display molecular association and promote growth and aggressiveness of tumor cells through STAT3 activation

African-American (AA) women with breast cancer (BC) are diagnosed with more aggressive disease, have higher risk of recurrence and poorer prognosis as compared to Caucasian American (CA) women. Therefore, it is imperative to define the factors associated with such disparities to reduce the unequal burden of cancer. Emerging data suggest that inherent differences exist in the tumor microenvironment of AA and CA BC patients, however, its molecular bases and functional impact have remained poorly understood. Here, we conducted cytokine profiling in serum samples from AA and CA BC patients and identified resistin and IL-6 to be the most differentially-expressed cytokines with relative greater expression in AA patients. Resistin and IL-6 exhibited positive correlation in serum levels and treatment of BC cells with resistin led to enhanced production of IL-6. Moreover, resistin also enhanced the expression and phosphorylation of STAT3, and treatment of BC cells with IL-6-neutralizing antibody prior to resistin stimulation abolished STAT3 phosphorylation. In addition, resistin promoted growth and aggressiveness of BC cells, and these effects were mediated through STAT3 activation. Together, these findings suggest a crucial role of resistin, IL-6 and STAT3 in BC racial disparity.

Resistin: insulin resistance to malignancy

Adipose tissue is recognized as an endocrine organ that secretes bioactive substances known as adipokines. Excess adipose tissue and adipose tissue dysfunction lead to dysregulated adipokine production that can contribute to the development of obesity-related co-morbidities. Among the various adipokines, resistin, which was initially considered as a determinant of the emergence of insulin resistance in obesity, has appeared as an important link between obesity and inflammatory processes. Several experimental and clinical studies have suggested an association between increased resistin levels and severe conditions associated with obesity such as cardiovascular disease and malignancies. In this review, we present the growing body of evidence that human resistin is an inflammatory biomarker and potential mediator of obesity-associated diseases. A common pathway seems to involve the combined alteration of immune and inflammatory processes that favor metabolic disturbances, atherosclerosis and carcinogenesis. The mode of action and the signaling pathways utilized by resistin in its interactions with target cells could involve oxidative and nitrosative stress. Therefore, resistin could function as a key molecule in the complications of obesity development and could potentially be used as a diagnostic and prognostic marker.