Adiponectin and resistin are associated with risk for myelodysplastic syndrome, independently from the insulin-like growth factor-I (IGF-I) system

The Kidney in Obesity: Current Evidence, Perspectives and Controversies

PURPOSE OF REVIEW

As obesity and chronic kidney disease (CKD) remain a public health issue, we aim to elaborate on their complex relationship regarding pathogenetic mechanisms and therapeutic potential as well. The purpose of this review is to enhance our understanding of the interplay between obesity and CKD in order to timely diagnose and treat obesity-related CKD.

RECENT FINDINGS

Obesity and CKD pose significant intertwined challenges to global health, affecting a substantial portion of the population worldwide. Obesity is recognized as an independent risk factor, intricately contributing to CKD pathogenesis through mechanisms such as lipotoxicity, chronic inflammation, and insulin resistance. Recent evidence highlights additional factors including hemodynamic changes and intestinal dysbiosis that exacerbate kidney dysfunction in obese individuals, leading to histologic alterations known as obesity-related glomerulopathy (ORG). This narrative review synthesizes current knowledge on the prevalence, pathophysiology, clinical manifestations, and diagnostic strategies of obesity-related kidney disease. Furthermore, it explores mechanistic insights to delineate current therapeutic approaches, future directions for managing this condition and controversies. By elucidating the multifaceted interactions between obesity and kidney health, this review aims to inform clinical practice and stimulate further research to address this global health epidemic effectively.

Serum and urinary levels of MIF, CD74, DDT and CXCR4 among patients with type 1 diabetes mellitus, type 2 diabetes and healthy individuals: Implications for further research

Background

Macrophage migration inhibitory factor (MIF) is a highly conserved cytokine with pleiotropic properties, mainly pro-inflammatory. MIF seems to exert its pro-inflammatory features by binding to its transmembrane cellular receptor CD74. MIF also has CXCR4, which acts as a co-receptor in this inflammatory process. Apart from MIF, D-dopachrome tautomerase (DDT) or MIF2, which belongs to the MIF superfamily, also binds to receptor CD74. Therefore, these molecules, MIF, CD74, DDT and CXCR4 are suggested to work together orchestrating an inflammatory process. Diabetes mellitus is characterised by chronic low-grade inflammation. Therefore, the aim of the present study was to evaluate serum and urinary levels of the aforementioned molecules among patients with type 1 diabetes mellitus (T1DM), type 2 diabetes mellitus (T2DM) and among healthy controls.

Methods

We enrolled 13 patients with T1DM, 74 patients with T2DM and 25 healthy individuals as controls. Levels of CD74, CXCR4, DDT, and MIF were measured using ELISA Kits according to the manufacturer's instructions.

Results

We documented increased serum MIF levels together with higher urinary CD74 levels among patients with T1DM, when compared to patients with T2DM and healthy adults. In particular, patients with T1DM showed significantly increased levels of MIF compared to T2DM (p = 0.011) and healthy controls (p = 0.0093). CD74 in urine were significantly higher in patients with T1DM compared to those affected with T2DM (p = 0.0302) and healthy group (p = 0.0099). On the contrary, serum CD74 were similar among the three groups. No statistical differences were identified in CXCR4 levels both in serum and in urine of all groups. Patients with T2DM and overweight/obesity had increased urinary levels of CD74, when compared to lean patients with T2DM.

Conclusion

The increased serum MIF levels and urinary CD74 levels among patients with T1DM may be attributed to the autoimmune milieu, which characterises patients with T1DM, when compared to patients with T2DM. These two findings merit further attention as they could pave the way for further research regarding the potential beneficial effects of inhibitors of MIF among patients with T1DM, especially in the early stages of T1DM. Finally, the role of inhibitors of MIF could be further explored in the context of obesity among patients with T2DM.

Paraneoplastic hypoglycemia: An overview for optimal clinical guidance

Paraneoplastic hypoglycemia, also known as non-islet cell tumor hypoglycemia (NICTH), is a rare but critical condition occurring in patients with different types of malignancy. This condition is commonly linked to tumors producing insulin-like growth (IGF) factors, particularly IGF-2 and its precursors, which disrupt glucose homeostasis and lead to excessive glucose consumption. The diagnosis typically involves documenting symptomatic hypoglycemia and ruling out other potential causes. Essential diagnostic tools include imaging studies and laboratory tests, specifically measuring IGF-2 levels and the IGF-2:IGF-1 ratio. Treatment strategies for NICTH are multifaceted and may include surgical resection of the tumor if feasible, pharmacological interventions such as corticosteroids to suppress IGF-2 production, or supportive measures to manage acute hypoglycemic episodes. Novel therapeutic approaches targeting IGF-2, such as monoclonal antibodies or siRNA, are also being explored and hold promise for future treatment options. This review aims to enhance understanding of paraneoplastic hypoglycemia, focusing on its pathogenesis and diagnosis, to guide optimal medical treatment.

Diet patterns, gut microbiota and metabolic disorders: Perspectives and challenges

The worldwide surge in obesity and associated metabolic disorders is emerging as a significant public health issue for societies and healthcare systems. Available evidence has shown that alterations in the gut microbiota could be implicated in the pathogenesis of obesity and associated disorders. A healthy gut microbiome is characterized by richness and high microbial diversity. Gut microbiota affect how the host responds to diet, and conversely, the host may modify the gut microbiota through changes in dietary habits. Diet can impact and alter the composition, diversity, and species richness of the gut microbiota over time. An unhealthy diet, high in fat and sugar, may lead to decreased microbial diversity, reduced synthesis of metabolites that maintain gut permeability, damage to the mucus layer, increased bacterial translocation and lipopolyssacharide which can trigger endotoxemia, chronic subclinical inflammation and metabolic disorders. Currently, the impact of diet on gut microbial composition and its involvement in the pathogenic mechanisms underlying metabolic disorders is one of the most promising areas of research in nutrition. This special issue has gathered original research articles in topics related to diet patterns, gut microbiota, obesity and associated metabolic disorders as well as brief reports, reviews and perspectives in the wider field of translational and clinical metabolic research. In particular, the aim of this Special Issue was to present evidence connecting gut microbiota with metabolic disorders, explore the underlying mechanisms of this association, and examine how diet patterns may influence this relationship.

Clinical metabolomics: Useful insights, perspectives and challenges

Metabolomics, a cutting-edge omics technique, is a rapidly advancing field in biomedical research, concentrating on the elucidation of pathogenetic mechanisms and the discovery of novel metabolite signatures predictive of disease risk, aiding in earlier disease detection, prognosis and prediction of treatment response. The capacity of this omics approach to simultaneously quantify thousands of metabolites, i.e. small molecules less than 1500 Da in samples, positions it as a promising tool for research and clinical applications in personalized medicine. Clinical metabolomics studies have proven valuable in understanding cardiometabolic disorders, potentially uncovering diagnostic biomarkers predictive of disease risk. Liquid chromatography-mass spectrometry is the predominant analytical method used in metabolomics, particularly untargeted. Metabolomics combined with extensive genomic data, proteomics, clinical chemistry data, imaging, health records, and other pertinent health-related data may yield significant advances beneficial for both public health initiatives, clinical applications and precision medicine, particularly in rare disorders and multimorbidity. This special issue has gathered original research articles in topics related to clinical metabolomics as well as research articles, reviews, perspectives and highlights in the broader field of translational and clinical metabolic research. Additional research is necessary to identify which metabolites consistently enhance clinical risk prediction across various populations and are causally linked to disease progression.

The role of adiposity, adipokines and polymorphisms of leptin and adiponectin in myelodysplastic syndromes

The aim of the present study was to investigate the relationship between leptin and adiponectin gene polymorphisms, circulating levels of leptin and adiponectin, adiposity and clinical markers in patients with myelodysplastic syndrome (MDS). This cross-sectional study was conducted with 102 adults and elderly MDS patients and 102 age- and sex-matched controls. Clinical characteristics, co-morbidities, anthropometric data, laboratory evaluation and genetic analysis (polymorphisms -2548G > A/rs7799039 of the LEP gene and +276G > T/rs1501299 of the ADIPOQ gene) were investigated. Serum leptin was higher and adiponectin lower in MDS when compared with controls. There was a significant positive correlation between serum leptin levels and BMI (r = 0·264, P = 0·025), waist circumference (r = 0·235, P = 0·047), body fat percentage (BF %) (r = 0·373, P = 0·001) and the fat mass index (FMI) (r = 0·371, P < 0·001). A lower mean adiponectin was found among patients with high BF %, higher visceral adiposity index and metabolic syndrome. A significant association was found between the AA genotype (mutant) of the LEP polymorphism rs7799039 and male sex and blast excess (≥ 5 %). In addition, a significant association was observed between the TT genotype (mutant) of the ADIPOQ rs1501299 polymorphism and Fe overload. These results demonstrate the importance of a comprehensive and systematic evaluation in patients with MDS in order to identify and control negative factors not related to the disease at an early stage.

Obesity and Leukemia: Biological Mechanisms, Perspectives, and Challenges

PURPOSE OF REVIEW

To examine the epidemiological data on obesity and leukemia; evaluate the effect of obesity on leukemia outcomes in childhood acute lymphoblastic leukemia (ALL) survivors; assess the potential mechanisms through which obesity may increase the risk of leukemia; and provide the effects of obesity management on leukemia. Preventive (diet, physical exercise, obesity pharmacotherapy, bariatric surgery) measures, repurposing drugs, candidate therapeutic agents targeting oncogenic pathways of obesity and insulin resistance in leukemia as well as challenges of the COVID-19 pandemic are also discussed.

RECENT FINDINGS

Obesity has been implicated in the development of 13 cancers, such as breast, endometrial, colon, renal, esophageal cancers, and multiple myeloma. Leukemia is estimated to account for approximately 2.5% and 3.1% of all new cancer incidence and mortality, respectively, while it represents the most frequent cancer in children younger than 5 years. Current evidence indicates that obesity may have an impact on the risk of leukemia. Increased birthweight may be associated with the development of childhood leukemia. Obesity is also associated with worse outcomes and increased mortality in leukemic patients. However, there are several limitations and challenges in meta-analyses and epidemiological studies. In addition, weight gain may occur in a substantial number of childhood ALL survivors while the majority of studies have documented an increased risk of relapse and mortality among patients with childhood ALL and obesity. The main pathophysiological pathways linking obesity to leukemia include bone marrow adipose tissue; hormones such as insulin and the insulin-like growth factor system as well as sex hormones; pro-inflammatory cytokines, such as IL-6 and TNF-α; adipocytokines, such as adiponectin, leptin, resistin, and visfatin; dyslipidemia and lipid signaling; chronic low-grade inflammation and oxidative stress; and other emerging mechanisms. Obesity represents a risk factor for leukemia, being among the only known risk factors that could be prevented or modified through weight loss, healthy diet, and physical exercise. Pharmacological interventions, repurposing drugs used for cardiometabolic comorbidities, and bariatric surgery may be recommended for leukemia and obesity-related cancer prevention.

Laboratory Findings and Biomarkers in Long COVID: What Do We Know So Far? Insights into Epidemiology, Pathogenesis, Therapeutic Perspectives and Challenges

Long COVID (LC) encompasses a constellation of long-term symptoms experienced by at least 10% of people after the initial SARS-CoV-2 infection, and so far it has affected about 65 million people. The etiology of LC remains unclear; however, many pathophysiological pathways may be involved, including viral persistence; a chronic, low-grade inflammatory response; immune dysregulation and a defective immune response; the reactivation of latent viruses; autoimmunity; persistent endothelial dysfunction and coagulopathy; gut dysbiosis; hormonal and metabolic dysregulation; mitochondrial dysfunction; and autonomic nervous system dysfunction. There are no specific tests for the diagnosis of LC, and clinical features including laboratory findings and biomarkers may not specifically relate to LC. Therefore, it is of paramount importance to develop and validate biomarkers that can be employed for the prediction, diagnosis and prognosis of LC and its therapeutic response, although this effort may be hampered by challenges pertaining to the non-specific nature of the majority of clinical manifestations in the LC spectrum, small sample sizes of relevant studies and other methodological issues. Promising candidate biomarkers that are found in some patients are markers of systemic inflammation, including acute phase proteins, cytokines and chemokines; biomarkers reflecting SARS-CoV-2 persistence, the reactivation of herpesviruses and immune dysregulation; biomarkers of endotheliopathy, coagulation and fibrinolysis; microbiota alterations; diverse proteins and metabolites; hormonal and metabolic biomarkers; and cerebrospinal fluid biomarkers. At present, there are only two reviews summarizing relevant biomarkers; however, they do not cover the entire umbrella of current biomarkers, their link to etiopathogenetic mechanisms or the diagnostic work-up in a comprehensive manner. Herein, we aim to appraise and synopsize the available evidence on the typical laboratory manifestations and candidate biomarkers of LC, their classification based on pathogenetic mechanisms and the main LC symptomatology in the frame of the epidemiological and clinical aspects of the syndrome and furthermore assess limitations and challenges as well as potential implications in candidate therapeutic interventions.

Myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are a family of myeloid cancers with diverse genotypes and phenotypes characterized by ineffective haematopoiesis and risk of transformation to acute myeloid leukaemia (AML). Some epidemiological data indicate that MDS incidence is increasing in resource-rich regions but this is controversial. Most MDS cases are caused by randomly acquired somatic mutations. In some patients, the phenotype and/or genotype of MDS overlaps with that of bone marrow failure disorders such as aplastic anaemia, paroxysmal nocturnal haemoglobinuria (PNH) and AML. Prognostic systems, such as the revised International Prognostic Scoring System (IPSS-R), provide reasonably accurate predictions of survival at the population level. Therapeutic goals in individuals with lower-risk MDS include improving quality of life and minimizing erythrocyte and platelet transfusions. Therapeutic goals in people with higher-risk MDS include decreasing the risk of AML transformation and prolonging survival. Haematopoietic cell transplantation (HCT) can cure MDS, yet fewer than 10% of affected individuals receive this treatment. However, how, when and in which patients with HCT for MDS should be performed remains controversial, with some studies suggesting HCT is preferred in some individuals with higher-risk MDS. Advances in the understanding of MDS biology offer the prospect of new therapeutic approaches.

Management of Hematologic Malignancies in the Era of COVID-19 Pandemic: Pathogenetic Mechanisms, Impact of Obesity, Perspectives, and Challenges

The COVID-19 pandemic brought about an unprecedented societal and healthcare system crisis, considerably affecting healthcare workers and patients, particularly those with chronic diseases. Patients with hematologic malignancies faced a variety of challenges, pertinent to the nature of an underlying hematologic disorder itself as well as its therapy as a risk factor for severe SARS-CoV-2 infection, suboptimal vaccine efficacy and the need for uninterrupted medical observation and continued therapy. Obesity constitutes another factor which was acknowledged since the early days of the pandemic that predisposed people to severe COVID-19, and shares a likely causal link with the pathogenesis of a broad spectrum of hematologic cancers. We review here the epidemiologic and pathogenetic features that obesity and hematologic malignancies share, as well as potential mutual pathophysiological links predisposing people to a more severe SARS-CoV-2 course. Additionally, we attempt to present the existing evidence on the multi-faceted crucial challenges that had to be overcome in this diverse patient group and discuss further unresolved questions and future challenges for the management of hematologic malignancies in the era of COVID-19.

Impact of obesity on survival of patients with myelodysplastic syndromes

Background: Obesity has been associated with increased incidence of myelodysplastic syndromes (MDS). Recently intriguing data in mouse models suggested that obesity increases survival in animals with MDS.Methods: This was a retrospective analysis using the Moffitt MDS database. Obesity was defined by using body mass index (BMI), whereby a BMI ≥ 30 was regarded as obese.Results: Among 3089 MDS patients with known BMI, 963 patients (31%) were categorized as obese. There were no differences in baseline characteristics between patients with BMI ≥ 30 and those with <30. The median OS for patients with BMI ≥ 30 was 34 months compared to 37 months for those with BMI < 30 (p 0.04). For patients with lower-risk MDS median OS was 52 months versus 57 months, respectively, (p 0.08) while for higher-risk patients median OS was 17 months for both groups. The rate of AML transformation was 36% for patients with BMI ≥ 30 compared to 32% for those with BMI < 30 (p 0.009). There was no difference in response to azacitidine. In multivariable analysis, BMI was associated with inferior OS. For patients < 45 years old, the median OS was 25 months for patients with BMI ≥ 30 compared to 116 months for those with BMI < 30 (p 0.034).Conclusions: Obesity is associated with inferior overall survival (OS) in MDS patients in less than 65 years old and lower MDS risk. Impact of obesity on the outcome of MDS is being explored in both mice and human. Here we reported the impact of obesity on OS in MDS patients. Obesity is associated with inferior OS in MDS patients particularly younger age groups and lower MDS risk.

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.

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.

Chemerin as a biomarker at the intersection of inflammation, chemotaxis, coagulation, fibrinolysis and metabolism in resectable non-small cell lung cancer

OBJECTIVES

Chemerin is an emerging adipocytokine at the intersection of inflammation, chemotaxis, thrombosis, fibrinolysis and metabolism. Our aims were 1) to explore circulating chemerin in resectable non-small cell lung cancer (NSCLC) taking into account its several interfaces; 2) to study its diagnostic potential; and 3) to assess its associations with clinicopathological features of NSCLC.

MATERIALS AND METHODS

In a large case-control study, serum chemerin, insulin resistance and lipid parameters, classic adipocytokines, inflammatory, coagulation, fibrinolysis and tumor biomarkers were determined in 110 consecutive patients with resectable NSCLC and 110 healthy controls matched on age (± 5 years), gender and date of blood draw (± 1 month).

RESULTS

NSCLC cases exhibited significantly elevated circulating chemerin compared to controls (p < 0.001). In NSCLC cases, chemerin was positively associated with Homeostasis model assessment score of insulin resistance (HOMA-IR), fibrinogen, plasminogen activity, tumor and inflammatory biomarkers, adiponectin, number of infiltrated lymph nodes and NSCLC stage. In control participants, circulating chemerin was positively correlated with somatometric, metabolic, lipid, hemostatic and inflammatory biomarkers, and leptin. Serum chemerin was independently associated with NSCLC, above and beyond NSCLC risk factors (OR: 2.20, 95% CI: 1.09-4.40, p = 0.03). In cases, hemostatic parameters (platelet count and plasminogen activity), HOMA-IR, CYFRA 21-1, creatinine and plant food consumption emerged as independent predictors of circulating chemerin (p < 0.05). Serum chemerin greater than 220 μg/L (cut-off point) yielded a sensitivity and a specificity of 63% and 91.8% respectively with a modest discriminative ability (AUC = 0.72, 95% C.I. 0.64-0.79) for the diagnosis of NSCLC.

CONCLUSION

Chemerin may represent a potentially useful biomarker in NSCLC integrating tumor-promoting networks, inflammatory and hemostatic mechanisms, and cancer-related metabolic pathways. More preclinical, prospective and longitudinal studies highlighting the pathogenetic role of chemerin in NSCLC are needed to corroborate and extend these data.

The Role of Adipokines in the Establishment and Progression of Head and Neck Neoplasms

Adipokines constitute a family of protein factors secreted by white adipose tissue (WAT), that regulate the functions of WAT and other sites. Leptin, adiponectin and resistin, are the main adipokines present in serum and saliva, targeting several tissues and organs, including vessels, muscles, liver and pancreas. Besides body mass regulation, adipokines affect glucose homeostasis, inflammation, angiogenesis, cell proliferation and apoptosis, and other crucial cell procedures. Their involvement in tumor formation and growth is well established and deregulation of adipokine and adipokine receptors' expression is observed in several malignancies including those located in the head and neck region. Intracellular effects of adipokines are mediated by a plethora of receptors that activate several signaling cascades including Janus kinase/ Signal transducer and activator of transcription (JAK/ STAT pathway), Phospatidylinositol kinase (PI3/ Akt/ mTOR) and Peroxisome proliferator-activated receptor (PPAR). The present review summarizes the current knowledge on the role of adipokines family members in carcinogenesis of the head and neck region. The diagnostic and prognostic significance of adipokines and their potential role as serum and saliva biomarkers are also discussed.

Hyperirisinemia is independently associated with subclinical hypothyroidism: correlations with cardiometabolic biomarkers and risk factors

PURPOSE

Irisin, a newly discovered adipo-myokine, is implicated in the modulation of the adipose phenotype, increasing energy expenditure and ameliorating systemic metabolism. Our aim was to investigate circulating irisin in subclinical hypothyroidism (SH) and study its associations with cardiometabolic risk factors.

METHODS

In a large case-control study, serum irisin, insulin resistance and lipid parameters, classic adipokines, inflammatory and hepatic biomarkers, and cardiovascular risk factors were determined in 120 consecutive patients with SH and 120 healthy controls matched on age, gender, and date of blood draw. Sixteen patients with SH received L-T4 treatment and, after 6 months, serum irisin and other biomarkers were assessed.

RESULTS

SH cases exhibited significantly higher circulating irisin than controls (p < 0.001). In all participants, irisin was positively associated with TSH, anti-TG, HOMA-IR, C-peptide, lipid and inflammatory biomarkers, leptin, and cardiovascular risk factors, including Framigham score and apolipoprotein B/apolipoprotein A-I. Irisin was negatively correlated with adiponectin, HDL-C, and thyroid hormones. Serum irisin was independently associated with SH, above and beyond body mass index and cardiometabolic factors (p = 0.02). TSH was an independent predictor of circulating irisin (p = 0.003). L-T4 therapy did not reverse considerably the hyperirisinemic status in treated SH patients (p = 0.09).

CONCLUSIONS

Irisin may represent an adipo-myokine counterbalancing a potential, gradual deterioration of lipid metabolism and insulin sensitivity in SH as well as reflecting a protective compensatory mechanism against oxidative muscle and thyroid cell stress. More mechanistic and prospective studies shedding light on the pathogenetic role of irisin in SH are needed to confirm and extend these data.

Kinetics of circulating fetuin-A may predict mortality independently from adiponectin, high molecular weight adiponectin and prognostic factors in critically ill patients with sepsis: A prospective study

PURPOSE

Fetuin-A and adiponectin, major hepatokine and adipokine respectively, have been implicated in systematic inflammation. Our aim was to jointly investigate whether kinetics of circulating fetuin-A, adiponectin and its isoform HMWA predict 28-day mortality in sepsis.

MATERIALS AND METHODS

In a prospective study, serum fetuin-A, adiponectin and HMWA were determined in 102 ICU patients fulfilling the diagnostic criteria of SEPSIS-3, at enrollment and one week after, and in 102 healthy controls matched on age and gender.

RESULTS

Serum fetuin-A was significantly lower in septic patients than controls (p<0.001). Among septic patients, those with septic shock and nonsurvivors presented lower fetuin-A, but higher adiponectin and HMWA compared to patients with sepsis and survivors respectively, both at baseline and day 7 (p<0.001). Fetuin-A exhibited negative correlations with APACHE II, CRP, procalcitonin, adiponectin and IL-6 but a positive one with albumin. Reduced fetuin-A as well as lower serum kinetics of fetuin-A (HR: 0.55, 95% C.I. 0.34-0.91, p=0.02), adiponectin but not HMWA were independently associated with 28-day mortality adjusting for age, gender, BMI, APACHE II, septic shock and laboratory biomarkers.

CONCLUSIONS

Circulating fetuin-A kinetics may be a prognostic biomarker in septic patients. More research is essential to elucidate fetuin-A's ontological role in sepsis pathophysiology.

Obesity over the life course and risk of acute myeloid leukemia and myelodysplastic syndromes

BACKGROUND

Overweight and obesity are known risk factors for a number of cancers, with recent evidence suggesting that risk of hematologic cancer is also increased in obese individuals. We evaluated associations between body mass index (BMI) at differing time points during the life course in population-based case control studies of acute myeloid leukemia (AML) and myelodysplatic syndromes (MDS).

METHODS

Cases were identified by the Minnesota Cancer Surveillance System. Controls were identified through the Minnesota State driver's license/identification card list. BMI was calculated using self-reported height and weight at ages 18, 35, and 50 years and two years prior to interview, and categorized as normal (18.5-25 kg/m(2)), overweight (25-29.9 kg/m(2)), obese class I (30-34.9 kg/m(2)), and obese class II/III (35+ kg/m(2)). All analyses were stratified by sex. Unconditional logistic regression was used to calculate odds ratios and 95% confidence intervals.

RESULTS

We included 420 AML cases, 265 MDS cases and 1388 controls. Obesity two years prior to diagnosis was associated with AML in both males and females (OR=2.22, 95% CI 1.28, 3.85 and OR=1.85, 95% CI 1.08, 3.15 for BMI≥35 vs. BMI 18.5-24.9, respectively). In contrast, associations between obesity and MDS were observed only in females. Weight change in adulthood was not consistently associated with either outcome.

CONCLUSION

Our results extend the emerging literature suggesting that obesity is a risk factor for hematologic malignancy and provide evidence that that the association remains regardless of timing of obesity. Obesity in adulthood is a modifiable risk factor for both MDS and AML.

Expression of adiponectin and its receptors is altered in epithelial ovarian tumors and ascites-derived ovarian cancer cell lines

OBJECTIVES

Recent evidence suggests that higher body mass index is associated with a modest increase in ovarian cancer risk. Reduced serum levels of adiponectin are correlated with obesity and increased cancer risk. The objectives of the present study are to determine if expressions of adiponectin and its receptors, AdipoR1 and AdipoR2, are altered in epithelial ovarian tumors and ascites-derived ovarian cancer cell lines and to determine if plasma adiponectin levels are altered in the chicken model of ovarian cancer.

METHODS

Adiponectin, AdipoR1, and AdipoR2 mRNA concentrations in ovaries and chicken ovarian cancer (COVCAR) cell lines were determined by quantitative real-time polymerase chain reaction analysis. Existence of adiponectin isoforms in the ovaries and COVCAR cells was identified by nondenaturing gel electrophoresis. Adiponectin, AdipoR1, and AdipoR2 protein amounts were determined by Western blot analysis. Plasma total adiponectin levels were determined by an enzyme immunoassay.

RESULTS

Adiponectin, AdipoR1, and AdipoR2 mRNA concentrations were significantly lower in cancerous ovaries and COVCAR cell lines compared with normal ovaries and normal ovarian surface epithelial (NOSE) cells, respectively. Adiponectin in ovary and COVCAR cell lines appeared as a heavy-molecular-weight isoform that is greater than 720-kd mass. In addition, a lower-molecular-weight adiponectin isoform was found in COVCAR cells but not in NOSE cells. Adiponectin and AdipoR1 protein concentrations were not different in COVCAR cell lines compared with NOSE cells. However, AdipoR2 protein concentrations were significantly higher in cancerous ovaries but lower in COVCAR cell lines compared with normal ovaries and NOSE cells, respectively. Plasma adiponectin concentrations were not different in chickens that had ovarian carcinoma compared with control animals.

CONCLUSIONS

Expression of adiponectin in ovarian tumors and in metastatic ovarian tumor cells is likely to affect cellular metabolism and proliferation through activating AdipoR1 and/or AdipoR2. Plasma adiponectin levels may not be predictive of advanced stages of ovarian tumor in the chicken model.

All in the family: Clueing into the link between metabolic syndrome and hematologic malignancies

Metabolic syndrome constitutes a constellation of findings including central obesity, insulin resistance/type 2 diabetes mellitus (DM), dyslipidemia and hypertension. Metabolic syndrome affects 1 in 4 adults in the United States and is rapidly rising in prevalence, largely driven by the dramatic rise in obesity and insulin resistance/DM. Being central to the development of metabolic syndrome and its other related diseases, much focus has been placed on identifying the mitogenic effects of obesity and insulin resistance/DM as mechanistic clues of the link between metabolic syndrome and cancer. Pertinent mechanisms identified include altered lipid signaling, adipokine and inflammatory cytokine effects, and activation of PI3K/Akt/mTOR and RAS/RAF/MAPK/ERK pathways via dysregulated insulin/insulin-like growth factor-1 (IGF-1) signaling. Through variable activation of these multiple pathways, obesity and insulin resistance/DM pre-dispose to hematologic malignancies, imposing the aggressive and chemo-resistant phenotypes typically seen in cancer patients with underlying metabolic syndrome. Growing understanding of these pathways has identified druggable cancer targets, rationalizing the development and testing of agents like PI3K inhibitor idelalisib, mTOR inhibitors everolimus and temsirolimus, and IGF-1 receptor inhibitor linsitinib. It has also led to exploration of obesity and diabetes-directed therapies including statins and oral hypoglycemic for the management of metabolic syndrome-related hematologic neoplasms.

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

Excess body weight is associated with various types of malignancies. Resistin, originally described as an adipocyte-specific hormone modulating insulin resistance in rodents, may exhibit proliferative, antiapoptotic, proinflammatory, proangiogenic and metastatic properties. Accumulating evidence supports a role of resistin as a risk factor and potential diagnostic and prognostic biomarker in cancer. In this report, the current knowledge about resistin's properties and pathophysiological implications in cancer in the context of dysregulated adipose tissue in obesity is summarized; clinical translations, preventive and therapeutic considerations, and future perspectives in the field of resistin research are discussed. At the same time, several enigmatic issues involving resistin receptor and signaling pathways remain to be clarified in order to unmask its ontological role in cancer pathophysiology.

Hyperresistinemia is associated with postmenopausal breast cancer

OBJECTIVE

The constellation of obesity, insulin resistance, and serum adipocytokine levels is associated with the risk and prognosis of postmenopausal breast cancer (PBC). Altered secretion of resistin may underlie the association between overweight/obesity and PBC. We thus explored the association of serum resistin with PBC, taking into account established risk factors, including adipokines and anthropometric, metabolic, and inflammatory markers.

METHODS

In a case-control study, we studied 102 postmenopausal women with pathologically confirmed, incident invasive breast cancer and 102 control participants matched on age and time of diagnosis between 2003 and 2010 at the Veterans' Administration General Hospital of Athens (NIMTS Hospital). Serum resistin, adiponectin, leptin, metabolic (homeostasis model assessment score of insulin resistance) and inflammatory (tumor necrosis factor-α, interleukin-6, and high-sensitivity C-reactive protein) parameters, and tumor markers (carcinoembryonic antigen and CA 15-3) were determined.

RESULTS

The mean serum resistin level was significantly higher in case participants than in control participants (P < 0.001) in both univariate and multivariable analyses, adjusting for age, date of diagnosis, education, family history of cancer, use of exogenous hormones, alcohol consumption, smoking status, physical activity, reproductive markers, metabolic markers, anthropometric (body mass index and weight circumference) markers, inflammatory markers, and adipokines (odds ratio, 1.17; 95% CI, 1.03-1.34; P = 0.02). In case participants, resistin level correlated significantly with tumor markers and inflammatory parameters, but not with metabolic and anthropometric variables.

CONCLUSIONS

Further prospective, longitudinal, and mechanistic studies are needed to determine whether hyperresistinemia is involved in the development of PBC or reflects changes during PBC progression and therefore could be used as a biomarker for PBC. Targeting resistin inhibition could be an effective therapeutic strategy in breast cancer by down-regulating the inflammatory microenvironment in breast tissue.

Higher fetuin-A, lower adiponectin and free leptin levels mediate effects of excess body weight on insulin resistance and risk for myelodysplastic syndrome

OBJECTIVE

Excess body weight has been implicated in the pathogenesis of myelodysplastic syndrome (MDS). We thus explored the role of serum fetuin-A reflecting ectopic hepatic fat deposition when storage capacity of adipocytes has been exceeded, free leptin reflecting overall fat mass and adiponectin reflecting visceral fat mass, all potential mediators of the effects of obesity on insulin resistance and, consequently, to MDS risk.

MATERIALS & METHODS

In a hospital-based case-control study, we studied 101 cases with incident, histologically confirmed primary MDS and 101 controls matched on gender, age and date of diagnosis, between 2004 and 2007. Serum fetuin-A, adiponectin, leptin, leptin receptor, free leptin and insulin were determined.

RESULTS

Higher serum fetuin-A, lower adiponectin and lower free leptin were all individually and independently associated with higher risk of MDS before and after controlling for matching and risk factors, such as age, gender, date of diagnosis, body mass index (BMI), family history of lymphohematopoietic cancer, smoking history and serum insulin. Interestingly, we have shown that these associations were prominent among overweight/obese individuals and persisted after controlling for BMI and serum insulin indicating that their effects are above and beyond insulinemia only.

CONCLUSION

Elevated serum fetuin-A but lower adiponectin and free leptin are associated with higher risk of MDS particularly among overweight/obese individuals. These findings suggest that the association between excessive weight gain and the risk of MDS could be mediated by fetuin-A, adiponectin and free leptin, which may have potential clinical and preventive implications.

Role of adiponectin and its receptors in cancer

Adiponectin (APN), a novel hormone/cytokine derived from adipocyte tissue, is involved in various physiological functions. Genetics, nutrition, and adiposity are factors contributing to circulating plasma concentrations of APN. Clinical correlation studies have shown that lower levels of serum APN are associated with increased malignancy of various cancers, such as breast and colon cancers, suggesting that APN has a role in tumorigenesis. APN affects insulin resistance, thus further influencing cancer development. Tumor cells may express receptors for APN. Cellular signaling is the mechanism by which APN exerts its host-protective responses. These factors suggest that serum APN levels and downstream signaling targets of APN may serve as potential diagnostic markers for malignancies. Further research is necessary to clarify the exact role of APN in cancer diagnosis and therapy.

Role of adipocytokines and its correlation with endocrine pancreatic function in patients with pancreatic cancer

INTRODUCTION

Some authors suggest that adipocytokines contribute to the induction of pancreatic carcinogenesis as well as the development of endocrine insufficiency.

AIMS

We evaluate the circulating concentrations of leptin, resistin and visfatin in patients with newly diagnosed pancreatic cancer (PC) and relationship between serum adipocytokines level and clinicopathological features of PC. Moreover the usefulness of those adipocytokines as possible biomarkers of endocrine pancreatic function in PC has been assessed.

METHODS

The pilot study group consisted of 45 individuals (mean age 65.6 ± 11.5 years, BMI 21.8 ± 3.4 kg/m(2)) with newly diagnosed PC (within last 1-3 months) and 13 healthy individuals with age, gender and BMI matched to the study group. Among PC patients 18 (40%) had recently diagnosed diabetes. Fasting plasma leptin, resistin, visfatin concentrations were determined with ELISA (R&D Systems, Phoenix Pharmaceuticals) and insulin by RIA (DakoCytomation).

RESULTS

Patients with PC as compared to controls had significantly lower plasma leptin (40.6 ± 21.3 vs 63.2 ± 16.3 pg/mL; p < 0,0008). In contrast PC patients showed more than six fold higher level of resistin (126.2 ± 143.2 vs 18.9 ± 7.2 ng/mL; p < 0.009) than controls. The median plasma visfatin was 2.8 ± 1.8 ng/mL, which was not significantly different from the controls (3.8 ± 1.1 ng/mL). When PC patients with and without diabetes were considered separately, plasma leptin concentrations among nondiabetic patients were slightly, but not significantly higher (44.6 ± 21.0) as compared to diabetics (34.5 ± 20.7). Moreover there was no difference between visfatin and resistin level in PC, among patients with and without diabetes. No significant differences between serum level of leptin, visfatin and resistin and age, gender, BMI, smoking status, tumor localization, distant metastases and pain has been found.

CONCLUSION

The results of this study confirm previous findings that patients with newly diagnosed pancreatic cancer are characterized with lower level of leptin. This pilot study showed significantly higher resistin concentrations in patients with PC in comparison to healthy controls, which may be helpful in PC early diagnosis. Changes in leptin and resistin level in PC are not likely related to endocrine disorders.

Metabolism-related cytokine and hormone levels in the serum of patients with myelodysplastic syndromes

BACKGROUND

A number of cytokines secreted from the bone marrow stromal cells and circulating hormones related to bone, adipose tissue and glucose metabolism might be involved in the pathogenesis of myelodysplastic syndromes (MDS).

METHODS

Serum levels of cytokines related to the metabolism of bone tissue [osteocalcin and parathyroid hormone (PTH)], adipose tissue (adiponectin, leptin and ghrelin) and glucose [insulin and insulin-like growth factor-1 (IGF-1)] were determined in 72 patients suffering from MDS, mostly of the low-risk group according to FAB classification, and 41 healthy individuals (controls).

RESULTS

Adiponectin and osteocalcin serum levels were significantly elevated in the MDS patients. Leptin, insulin and IGF-1 serum levels were reduced. No difference was found in the serum levels of PTH and ghrelin. Leptin levels were reversibly associated with patient blast count.

CONCLUSION

Increased serum levels of adiponectin and low levels of IGF-1 in MDS patients may counterbalance the increased rate of apoptosis in the pool of hematopoietic progenitors. Osteocalcin secreted by osteoblasts regulates the renewal and proliferation of hematopoietic stem cells. Hormones and cytokines either secreted by the cells of the bone marrow stroma or transferred by the microcirculation act on hematopoietic progenitors and may regulate their differentiation, apoptosis and proliferation rate in MDS.

Serum resistin: a biomarker of breast cancer in postmenopausal women? Association with clinicopathological characteristics, tumor markers, inflammatory and metabolic parameters

OBJECTIVE

Previous few studies have shown that resistin is significantly elevated in breast cancer (BC) patients. Therefore, we investigated whether serum resistin could be used as a potential diagnostic and prognostic tool for postmenopausal BC (PBC), taking into account clinicopathological features, serum tumor markers, anthropometric, metabolic, and, for the first time, inflammatory parameters.

METHODS

Serum resistin, tumor markers (CA 15-3 and CEA), metabolic, anthropometric and inflammatory parameters (TNF-α, IL-6, hsCRP) were determined in 103 postmenopausal women with incident, pathologically confirmed, invasive BC, 103 controls matched on age and time of diagnosis, and 51 patients with benign breast lesions (BBL).

RESULTS

Mean serum resistin was significantly higher in cases than in controls and patients with BBL (p<0.001). In patients, resistin was significantly associated with tumor and inflammatory markers, cancer stage, tumor size, grade and lymph node invasion but not with anthropometric, metabolic parameters and hormone receptor status. Multivariable regression analysis revealed that serum IL-6 (p=0.02) and cancer stage (p=0.048) were the strongest determinants of serum resistin in cases adjusting for demographic, metabolic and clinicopathological features. Although resistin's diagnostic performance was low based on ROC curve analysis [0.72, 95% CI: 0.64-0.79], it could, however, represent a BC biomarker reflecting advanced disease stage and inflammatory state.

CONCLUSION

Further prospective and longitudinal studies are needed to evaluate whether serum resistin could be used as a prognostic tool in BC monitoring and management. More research is essential to elucidate resistin's ontological role in the association between obesity, representing a chronic low-grade subclinical inflammation, and PBC.

The role of adiponectin in cancer: a review of current evidence

Excess body weight is associated not only with an increased risk of type 2 diabetes and cardiovascular disease (CVD) but also with various types of malignancies. Adiponectin, the most abundant protein secreted by adipose tissue, exhibits insulin-sensitizing, antiinflammatory, antiatherogenic, proapoptotic, and antiproliferative properties. Circulating adiponectin levels, which are determined predominantly by genetic factors, diet, physical activity, and abdominal adiposity, are decreased in patients with diabetes, CVD, and several obesity-associated cancers. Also, adiponectin levels are inversely associated with the risk of developing diabetes, CVD, and several malignancies later in life. Many cancer cell lines express adiponectin receptors, and adiponectin in vitro limits cell proliferation and induces apoptosis. Recent in vitro studies demonstrate the antiangiogenic and tumor growth-limiting properties of adiponectin. Studies in both animals and humans have investigated adiponectin and adiponectin receptor regulation and expression in several cancers. Current evidence supports a role of adiponectin as a novel risk factor and potential diagnostic and prognostic biomarker in cancer. In addition, either adiponectin per se or medications that increase adiponectin levels or up-regulate signaling pathways downstream of adiponectin may prove to be useful anticancer agents. This review presents the role of adiponectin in carcinogenesis and cancer progression and examines the pathophysiological mechanisms that underlie the association between adiponectin and malignancy in the context of a dysfunctional adipose tissue in obesity. Understanding of these mechanisms may be important for the development of preventive and therapeutic strategies against obesity-associated malignancies.

Elevated serum visfatin/nicotinamide phosphoribosyl-transferase levels are associated with risk of postmenopausal breast cancer independently from adiponectin, leptin, and anthropometric and metabolic parameters

OBJECTIVE

Obesity has been implicated in the etiology of postmenopausal breast cancer (PBC). We hypothesized that altered secretion of visfatin may underlie this association. We thus investigated the association of serum visfatin with PBC risk, taking into account known risk factors including adipokines and anthropometric and metabolic parameters.

METHODS

In a case-control study, we studied 102 postmenopausal women with pathologically confirmed, incident invasive breast cancer and 102 control women matched on age and time of diagnosis between 2003 and 2010 at Army Share Fund Hospital, Veterans' Hospital (NIMTS). Levels of serum visfatin, adiponectin, leptin, metabolic parameters, carcinoembryonic antigen, and CA 15-3 were determined.

RESULTS

The mean serum visfatin level was significantly higher in case than in control participants (P < 0.001). Women in the highest quartile of visfatin concentration presented significantly higher odds for PBC, adjusting for age, date of diagnosis, education, body mass index, waist circumference, years with menstruation, parity/age at first full-term pregnancy, breast-feeding, family history of cancer, use of exogenous hormones, alcohol consumption, smoking status, homeostasis model assessment score, and serum leptin and adiponectin concentrations (odds ratio, 7.93; 95% CI, 2.52-24.9). In case participants, the visfatin level correlated significantly with the tumor marker CA 15-3 (P = 0.03) but not with metabolic and anthropometric variables (P > 0.05).

CONCLUSIONS

Further prospective studies are needed to determine whether an elevated serum visfatin level is implicated in the etiopathogenesis of PBC or reflects changes during PBC progression and could therefore be used as a biomarker for PBC.

Could serum visfatin be a potential biomarker for postmenopausal breast cancer?

OBJECTIVE

Previous studies have shown that visfatin is significantly elevated in patients with gastric carcinoma and postmenopausal breast cancer (PBC). We thus explored whether serum visfatin could be used as a potential diagnostic and prognostic tool for PBC, taking into account clinicopathological features, serum tumor markers, anthropometric and metabolic parameters.

METHODS

Serum visfatin, tumor marker CA 15-3, carcinoembryonic antigen, metabolic and anthropometric parameters were determined in 103 postmenopausal women with pathologically confirmed, incident invasive breast cancer, 103 controls matched on age and time of diagnosis, and 51 patients with benign breast lesions (BBL).

RESULTS

Mean serum visfatin was significantly higher in cases than in controls and patients with BBL (p<0.001). In cases, visfatin was significantly associated with CA 15-3 (p=0.03), hormone-receptor status (p<0.001), lymph node invasion (p=0.06) but not with metabolic and anthropometric variables (p>0.05). Multivariable regression analysis revealed that absence of estrogen and progesterone receptors (ER-PR-) was the strongest significant determinant of serum visfatin (p<0.001) in cases adjusting for demographic, metabolic and clinicopathological features. Based upon receiver operator characteristic analysis, serum visfatin outperformed CA 15-3 only in discriminating between PBC cases with early cancer stage than those with late stage, and in differentiating particularly patients with ER-PR- breast tumors.

CONCLUSION

Further prospective and longitudinal studies are needed to determine whether serum visfatin could be used as a prognostic tool in the armamentarium of PBC monitoring and management in conjunction with other biomarkers.

Circulating adiponectin is inversely associated with risk of thyroid cancer: in vivo and in vitro studies

CONTEXT

Circulating adiponectin has been inversely associated with risk for several malignancies. Its association with thyroid cancer has not yet been evaluated.

OBJECTIVE/METHODS

We measured circulating adiponectin levels in 175 thyroid carcinoma patients and 107 controls. We also examined the expression of adiponectin receptors (AdipoR1 and AdipoR2) using immunohistochemistry in 82 thyroid carcinoma tissues and using RT-qPCR in 40 human thyroid carcinoma tissues (32 papillary, six follicular/Hurthle, one anaplastic, one medullary), four normal human thyroid tissue specimens, and the BHP7 and SW579 thyroid cancer cell lines. We then utilized these thyroid cancer cell lines to investigate whether adiponectin could directly regulate cell cycle or apoptosis.

RESULTS

Thyroid cancer patients had lower circulating adiponectin levels than controls (17.00 ± 6.32 vs. 19.26 ± 6.28 μg/ml; P < 0.001). Subjects in the highest tertile of circulating adiponectin concentrations had significantly lower odds of developing any type of thyroid carcinoma (odds ratio = 0.29; 95% confidence interval, 0.16-0.55), or papillary thyroid carcinoma (odds ratio = 0.27; 95% confidence interval, 0.14-0.55), before and after adjustment for potential confounders. Both thyroid carcinoma cell lines and tissues expressed AdipoR1 and AdipoR2. Recombinant adiponectin did not exert a clinically significant direct effect on cell cycle, proliferation, or apoptosis in thyroid cancer cell lines in vitro.

CONCLUSIONS

Circulating adiponectin is independently and inversely associated with the risk of thyroid cancer. Human thyroid carcinomas and cell lines express adiponectin receptors. However, in the absence of a major direct effect of adiponectin on thyroid cancer cell lines in vitro, the negative association observed herein may be attributed to the metabolic effects of adiponectin.

The association of serum adiponectin levels with histopathological variables in gastric cancer patients

Adiponectin is a peptide hormone secreted from the adipose tissue, affecting the proliferation and insulin sensitivity in different cell types. The levels of adiponectin have been found to be decreased in hyperinsulinemia and insulin resistant states, such as obesity. The previous studies have suggested that plasma adiponectin levels are decreased in patients with endometrial and breast cancer. In our study, the relationship among serum adiponectin levels, demographic features and histopathological variables was evaluated in gastric cancer patients. Forty consecutive patients with gastric cancer who underwent gastrectomy with standard lymph node dissection were included and 43 healthy controls were included in this study. The serum levels of glucose, insulin, C-peptide, HbA1c and adiponectin were measured in both groups. We analyzed the correlation among these parameters and patients' demographic features, such as age, gender, body mass index (BMI) and histopathological variables such as tumor localization, stage, nodal status, histological grade, vascular and lymphatic invasion. The mean age was 60.05+9.72 in patients, while it was 38.6+12.73 in controls. The mean serum adiponectin levels were 12.62+7.9 and 10.07+6.72 ng/ml, respectively, in groups. There was no different in terms of adiponectin, C-peptide, HOMA-R level in both groups. On the other hand, BMI, glucose and insulin levels were significantly different in gastric cancer patients in comparison with the controls. There was no correlation among the levels of adiponectin, BMI, insulin and c-peptide levels in patient group (P>0.05). The adiponectin levels of woman were significantly lower than male patients (P=0.002). No relations were detected among tumor stage, tumor localization, nodal status, lymphatic and vascular invasion, and the levels of serum adiponectin (P>0.05). Interestingly, a positive correlation was found between tumor grade and plasma adiponectin levels (r=0.372; P=0.018). Our results suggest that plasma adiponectin levels were similar in both patients with gastric cancer and the controls. In addition, no correlation was found between adiponectin levels and demographic features and histopathological variables of patients. But, in undifferentiated tumors, plasma adiponectin level was significantly higher than well-differentiated grade tumors.

Adiponectin is produced by lymphocytes and is a negative regulator of granulopoiesis

Lymphocytes have long been established to play an important role in the regulation of hematopoiesis and produce many cytokines that act on hematopoietic progenitor cells. Previous studies by our group have shown that normal, unstimulated lymphocytes produce a protein that inhibits normal bone marrow GM colony formation. Adiponectin is an adipokine that has been demonstrated to act as a negative regulator of hematopoiesis and immune function. This study aimed to determine if the inhibitory molecule that we described previously was adiponectin. Here, we show transcription, translation, and secretion of adiponectin from lymphocytes and demonstrate that its receptors, AdipoR1 and AdipoR2, are expressed by bone marrow MNCs. We show that although the adiponectin expression is low in lymphocytes, it is sufficient to induce a significant inhibitory effect on GM precursors (CFU-GM) and activate the AMPK pathway in these cells. The regulation of adiponectin production by lymphocytes and its detailed function in suppressing GM colony formation need to be elucidated now. Our findings suggest a functional role for adiponectin as a negative regulator of granulopoiesis.

B-cell chronic lymphocytic leukemia risk in association with serum leptin and adiponectin: a case-control study in Greece

AIM

Leptin and adiponectin are two well-studied adipokines in relation to malignancies. In this study, we examined the association between leptin/adiponectin and risk of B-cell chronic lymphocytic leukemia (B-CLL), as well as the relationships between adipokines and several established prognostic factors of B-CLL.

METHODS

Ninety-five patients with incident B-CLL and 95 hospital controls matched on age and gender were studied between 2001 and 2007, and blood samples were collected. Leptin, total and high molecular weight adiponectin, and prognostic markers of B-CLL were determined.

RESULTS

Cases had a higher body mass index (BMI) than controls (p = 0.01) and lower levels of leptin (p < 0.01). Significantly more cases than controls presented a family history of lymphohematopoietic cancer (LHC) (p = 0.01). Higher serum leptin levels were associated with lower risk of B-CLL adjusting for age, gender, family history of LHC, BMI and serum adiponectin; the multivariate odds ratio comparing highest to lowest tertile was 0.05 (95% CI 0.01-0.29, p trend < 0.001); Adiponectin was not significantly different between cases and controls.

CONCLUSION

Leptin was found to be inversely associated with risk of CLL but in contrast to prior studies of CLL and hematologic malignancies, this study found no significant association between CLL and adiponectin.

Adipocytokines as new promising markers of colorectal tumors: adiponectin for colorectal adenoma, and resistin and visfatin for colorectal cancer

Adipocytokines are adipocyte-secreted hormones associated with some malignancies such as colorectal, breast, and prostate cancer. We hypothesized that changes in the levels of adipocytokines may indicate the carcinogenesis and progression of colorectal cancer and adenoma, and investigated the association of the blood levels of several adipocytokines through a case-control study. Blood levels of adiponectin, leptin, resistin, visfatin, and C-peptide at diagnosis were measured in 115 colorectal cancer patients and 115 age-, sex-, and body mass index-matched controls. The same analysis was performed in 72 colorectal adenoma patients and 72 controls. Logistic regression models were used for estimating odds ratios and 95% confidence intervals, and one-way anova was performed to determine the prevalence of each variable between two or more groups. Resistin and visfatin levels in cancer patients were significantly higher than those of controls on multivariate analysis (P = 0.03 and P < 0.01, respectively). Stage progression significantly correlated with resistin and visfatin levels (P < 0.01 for both). The adiponectin level in adenoma patients was significantly lower than that of controls on multivariate analysis (P = 0.04). Its level was inversely correlated with the number of adenoma (P = 0.02), but not correlated with the size of adenoma. Resistin and visfatin may be good biomarkers of colorectal malignant potential and stage progression. Adiponectin level may be a good biomarker of colorectal adenoma.

Adipocytokines and squamous cell carcinoma of the esophagus

PURPOSE

Adipocytokines are adipocyte-secreted hormones associated with some malignancies. It has been reported that the impaired response of adipocytokines to body weight loss may play a role in the pathogenesis of cancer-induced cachexia. We investigated the association between adipocytokines with squamous cell carcinoma of the esophagus (SCCE).

METHODS

The levels of body mass index (BMI) and adiponectin, leptin, resistin, visfatin and C-peptide in the blood at diagnosis were measured in 117 SCCE patients and 117 age- and sex-matched controls. Logistic regression models were employed to estimate odds ratio. One-way analysis was performed to examine the prevalence of variables between two or more groups. A non-parametric Spearman correlation test was conducted to examine the associations between BMI and other variables.

RESULTS

Adiponectin and BMI levels were significantly lower, and resistin level was significantly higher in the patients on multivariate analysis (P = 0.01, <0.01 and <0.01 respectively). BMI gradually decreased with stage progression, and resistin level gradually increased with stage progression (P < 0.01 for both). The inverse correlation between BMI and adiponectin was comparatively strong in the controls, but was weak in the patients. Leptin showed comparatively strong correlation with BMI in the controls, but was weakly correlated in the patients. The correlation between BMI and resistin or C-peptide was demonstrated weakly only in the controls, and visfatin did not correlate with BMI.

CONCLUSIONS

Resistin may be a biomarker for the progression of SCCE. In addition, the impaired responses to body weight loss of adiponectin and leptin in the patients with SCCE were suggested.

Adipocytokine levels in gastric cancer patients: resistin and visfatin as biomarkers of gastric cancer

PURPOSE

Adipocytokines are adipocyte-secreted hormones associated with some malignancies. We investigated the association of adipocytokines with gastric cancer.

METHODS

The levels of body mass index (BMI) and adiponectin, leptin, resistin, visfatin, and C-peptide in blood at diagnosis were measured in 156 gastric cancer patients and 156 age- and sex-matched controls. Logistic regression models were used to estimate odds ratio, and one-way analysis of variance was performed to examine the prevalence of each variable between 2 or more groups.

RESULTS

Adiponectin, C-peptide and BMI levels were significantly lower, and resistin and visfatin levels were significantly higher in the patients on multivariate analysis (P=0.0004, 0.0006, 0.0051, 0.0006 and 0.0013, respectively). In the controls, the inverse correlation between BMI and adiponectin was comparatively strong, but was weak in the patients. The correlation between BMI and leptin was strong in both the controls and the patients. The correlation between BMI and resistin or visfatin was not clear in either the patients or the controls. The correlation between BMI and C-peptide was not clear in the controls, but might be weak in the patients. Leptin, C-peptide and BMI levels gradually decreased with stage progression, and resistin and visfatin levels gradually increased with stage progression (P<0.0001 for all). Comparison between 38 patients with Stage I gastric cancer and the controls showed that adiponectin level tended to decrease in the patients (P=0.0582), and BMI level was not different between two groups (P=0.2480).

CONCLUSIONS

Resistin and visfatin may be good biomarkers of gastric cancer.

Obesity, weight gain, and risk of chronic myeloid leukemia

To date, little is known about the risk factors for the development of chronic myeloid leukemia (CML). Obesity, measured as body mass index, has been identified as a possible risk factor for several solid tumors as well as some adult hematopoietic malignancies. This case-control study (N = 253 cases and 270 controls), conducted at the University of Texas M. D. Anderson Cancer Center, investigated the role of obesity and adulthood weight gain in CML risk. Cases and controls were similar with respect to smoking, alcohol consumption, and occupational solvent and ionizing radiation exposure. Cases were significantly more likely to have a history of occupational exposure to agricultural chemicals (11% cases versus 3% controls, P = 0.001). Cases were more likely to be obese during adulthood compared with controls at age 25 [odds ratios (OR) = 4.29; 95% confidence intervals (95% CI), 1.63-11.3], at age 40 (OR = 5.12; 95% CI, 1.92-13.6), and at diagnosis (OR = 3.09; 95% CI, 1.56-6.13). Obesity at all ages was found to be an independent risk factor, with a significant dose-response effect. Among participants > or =45 years, cases gained significantly more weight each year between ages 25 and 40 compared with controls (0.78 versus 0.44 kg/y, P < 0.001) with the association strongest among those who gained >1 kg/y between 25 and 40 years of age (OR, 3.63; 95% CI, 1.46-9.04). Our results suggest that obesity and adulthood weight gain play important roles in CML risk. Several plausible biological mechanisms have been proposed and warrant further investigation. In the future, cancer prevention interventions aimed at reducing the incidence of CML could be developed.