Preoperative serum visfatin levels and prognosis of breast cancer among Chinese women

Obesity and multiple myeloma: emerging mechanisms and perspectives

Obesity is a global pandemic that has been associated with the development of breast, endometrial, large intestine, renal, esophageal, and pancreatic cancer. Obesity is also involved in the development of cardiovascular disease and type 2 diabetes mellitus. Recently, an increase in the incidence of obesity-related cancers has been reported. Multiple myeloma (MM) is the second most common hematological malignancy, after lymphoma. The aim of this review is to examine the epidemiological data on obesity and MM, assess the effect of obesity on MM outcomes, evaluate the possible mechanisms through which obesity might increase the incidence of MM and provide the effects of obesity management on MM. Current evidence indicates that obesity may have an impact on the progression of monoclonal gammopathy of undetermined significance (MGUS) to MM and increase the prevalence of MM. However, data regarding the effect of obesity on MGUS incidence are controversial; further studies are needed to examine whether obesity affects the development of MGUS or the progression of MGUS to MM. In addition, obesity affects MM outcomes. Increased BMI is associated with decreased survival in patients with MM, while data regarding the effect of obesity on newly diagnosed MM subjects and autologous stem cell transplantation are limited. Interestingly, the obesity paradox may also apply to patients with relapsed/refractory MM who are overweight or obese, because they may have a survival advantage. The pathophysiological pathways linking obesity to MM are very complicated and include bone marrow adipose tissue; adipokines, such as adiponectin, leptin, resistin, and visfatin; inflammatory cytokines and growth factors, such as TNF-α and IL-6; hormones including insulin and the insulin-like growth factor system as well as sex hormones. In terms of the effect of pharmacological management of obesity, orlistat has been shown to alter the proliferation of MM cells, whereas no data exist on glucagon-like peptide-1 receptor agonists, naltrexone/bupropion, or phentermine/topiramate. Bariatric surgery may be associated with a reduction in the incidence of MM, however, further studies are needed.

Cellular and molecular insights into the roles of visfatin in breast cancer cells plasticity programs

Obesity has reached a pandemic proportion and is responsible for the augmentation of multimorbidity including certain cancers. With the rise in obesity amongst the female population globally, a concomitant increase in breast cancer (BC) incidence and related mortality has been observed. In the present review, we have elucidated the cellular and molecular insight into the visfatin-mediated cellular plasticity programs such as Epithelial to mesenchymal transition (EMT) and Endothelial to mesenchymal transition (EndoMT), and stemness-associated changes in BC cells. EMT and EndoMT are responsible for inducing metastasis in cancer cells and conferring chemotherapy resistance, immune escape, and infinite growth potential. Visfatin, an obesity-associated adipokine implicated in metabolic syndrome, has emerged as a central player in BC pathogenesis. Several studies have indicated the presence of visfatin in the tumor microenvironment (TME) where it augments EMT and EndoMT of BC cells. Further, Visfatin also modulates the TME by acting on the tumor stroma cells such as adipocytes, infiltrated immune cells, and adipose-associated stem cells that secrete factors such as cytokines, and extracellular vesicles responsible for augmenting cellular plasticity program. Visfatin induced altered metabolism of the cancer cells and molecular determinants such as non-coding RNAs involved in EMT and EndoMT have been discussed. We have also highlighted specific therapeutic targets that can be exploited for the development of effective BC treatment. Taken together, these advanced understandings of cellular and molecular insight into the visfatin-mediated cellular plasticity programs may stimulate the development of better approaches for the prevention and therapy of BC, especially in obese patients.

Updated Functional Roles of NAMPT in Carcinogenesis and Therapeutic Niches

Simple Summary

The advantages and applications of using the non-invasive way to detect serum biomarkers for assessing cancer diagnosis and prognosis have been explored. Nicotinamide phosphoribosyltransferase (NAMPT), also designated as pre-B-cell colony-enhancing factor (PBEF) or visfatin, is a secreted adipokine known to modulate tumor malignancies. Its significance in predicting cancer patient’s survival outcome further renders the implementation of NAMPT in clinical practice. In this review, recent discoveries of NAMPT in cancer studies were focused and integrated. We aim to provide updates for researchers who are proposing relevant objectives.

Abstract

Nicotinamide phosphoribosyltransferase (NAMPT) is notable for its regulatory roles in tumor development and progression. Emerging evidence regarding NAMPT somatic mutations in cancer patients, NAMPT expressional signatures in normal tissues and cancers, and the prognostic significance of NAMPT in many cancer types has attracted attention, and NAMPT is considered a potential biomarker of cancer. Recent discoveries have demonstrated the indirect association and direct biological functions of NAMPT in modulating cancer metastasis, proliferation, angiogenesis, cancer stemness, and chemoresistance to anticancer drugs. These findings warrant further investigation of the underlying mechanisms to provide knowledge for developing novel cancer therapeutics. In this review article, we explore recent research developments involving the oncogenic activities of NAMPT by summarizing current knowledge regarding NAMPT somatic mutations, clinical trials, transcriptome data, and clinical information and discoveries related to the NAMPT-induced signaling pathway in modulating hallmarks of cancer. Furthermore, the comprehensive representation of NAMPT RNA expression in a pancancer panel as well as in specific normal cell types at single-cell level are demonstrated. The results suggest potential sites and cell types that could facilitate NAMPT-related tumorigenesis. With this review, we aim to shed light on the regulatory roles of NAMPT in tumor development and progression, and provide information to guide future research directions in this field.

Adipocytokines visfatin and resistin in breast cancer: Clinical relevance, biological mechanisms, and therapeutic potential

Obesity is one of the major modifiable risk factors in breast cancer, with obese adipose tissue showing a pathological role in breast cancer development and malignancy via the release of secretory factors, such as proinflammatory cytokines and adipocytokines. The current article focuses on visfatin and resistin, two such adipocytokines that have emerged over the last two decades as leading breast cancer promoting factors in obesity. The clinical association of circulating visfatin and resistin with breast cancer and their biological mechanisms are reviewed, in addition to their role in the context of tumor-stromal interactions in the breast cancer microenvironment. Recent findings have unraveled several mediators of visfatin and resistin that are involved in the crosstalk between breast cancer cells and adipose tissue in the breast tumor microenvironment, including growth differentiation factor 15 (GDF15), interleukin 6 (IL-6), and toll-like receptor 4 (TLR4). Finally, current therapeutics targeting visfatin and resistin and their respective pathways are discussed, including future therapeutic strategies such as new drug design or neutralizing peptides that target extracellular visfatin or resistin. These hold promise in the development of novel breast cancer therapies and are of increasing relevance as the prevalence of obesity-related breast cancer increases worldwide.

Prognostic value of visfatin in various human malignancies: A systematic review and meta-analysis

Although numerous studies have shown that visfatin is linked to several cancers, its prognostic value is still unclear. This first comprehensive meta-analysis was performed to evaluate the prognostic effect of visfatin in cancer patients. A systematic search was conducted for relevant studies in health-related electronic databases up to May 2019. The pooled hazard ratios (HRs) and ORs with 95% confidence intervals (CIs) for total and stratified analyses were calculated to demonstrate the prognostic value of visfatin expression level in cancer patients. Heterogeneity and publication bias were also investigated. A total of 14 eligible studies with 1616 patients were included in the current meta-analysis. Pooling results revealed that, high visfatin expression was significantly associated with poorer overall survival (OS) (HR = 2.43, 95% CI 1.64-3.62, P < 0.001). Elevated visfatin level was also correlated with positive lymph node metastasis (OR = 2.45, 95% CI 1.43-4.17, P ≤ 0.001), positive distance metastasis (OR = 2014, 95% CI 1.25-3.69, P ≤ 0.001), advanced tumor stage (OR = 3.01, 95% CI 1.91-7.72, P ≤ 0.001), and larger tumor size (OR = 1.99, 95% CI 1.49-2.69, P ≤ 0.001). Our meta-results indicates that altered visfatin expression is a potential indicator of poor clinical outcomes in tumor patients, suggesting that high visfatin expression may serve as a potential biomarker of poor prognosis and metastasis in cancers.

Dietary Antioxidant Trans-Cinnamaldehyde Reduced Visfatin-Induced Breast Cancer Progression: In Vivo and In Vitro Study

Excessive growth of cancer cells is the main cause of cancer mortality. Therefore, discovering how to inhibit cancer growth is an important research topic. Recently, the newly discovered adipokine, known as nicotinamide phosphoribosyl transferase (NAMPT, visfatin), which has been associated with metabolic syndrome and obesity, has also been found to be a major cause of cancer proliferation. Therefore, inhibition of NAMPT and reduction of Nicotinamide adenine dinucleotide (NAD) synthesis is one strategy for cancer therapy. Cinnamaldehyde (CA), as an antioxidant and anticancer natural compound, may have the ability to inhibit visfatin. The breast cancer cell line and xenograft animal models were treated under different dosages of visfatin combined with CA and FK866 (a visfatin inhibitor) to test for cell toxicity, as well as inhibition of tumor-related proliferation of protein expression. In the breast cancer cell and the xenograft animal model, visfatin significantly increased proliferation-related protein expression, but combination with CA or FK866 significantly reduced visfatin-induced carcinogenic effects. For the first time, a natural compound inhibiting extracellular and intracellular NAMPT has been demonstrated. We hope that, in the future, this can be used as a potential anticancer compound and provide further directions for research.

Relationship between NAMPT/PBEF/visfatin and prognosis of patients with malignant tumors: a systematic review and meta-analysis

Background

Nicotinamide phosphoribosyltransferase (NAMPT), also known as pre-B-cell colony-enhancing factor (PBEF) or visfatin, has been reported to be a crucial factor involved in tumor metabolism, angiogenesis and cell apoptosis. However, its definite roles in patients with malignant cancer remain unclear.

Methods

Three online databases PubMed, Embase and Web of Science were looked through comprehensively for eligible articles, published before November, 2018. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) of overall survival (OS) or disease-free survival time or recurrence-free survival (DFS/RFS) were calculated to determine the associations between NAMPT expression and cancer prognosis.

Results

A total of ten eligible studies were finally enrolled for this analysis. Our results indicated that elevated NAMPT expression was associated with poor OS in breast cancer by both univariate and multivariate analysis (pooled HR =3.23, 95% CI: 1.93-5.41, I²=21.1%, P=0.283; pooled HR =3.34, 95% CI: 2.13-5.22, I²=0.0%, P=0.791; respectively) and in gastric cancer by univariate analysis (pooled HR =2.47, 95% CI: 1.07-5.73, I²=91.1%, P=0.001). Moreover, high expression of NAMPT was also related to poor DFS/RFS in breast cancer by univariate and multivariate analysis (pooled HR =3.85, 95% CI: 2.59-5.71, I²=0.0%, P=0.700; pooled HR =3.43, 95% CI: 2.36-4.99, I²=0.0%, P=0.737; separately). Similar results could be found in urothelial carcinoma (pooled HR =3.14, 95% CI: 1.73-5.71, I²=47.8%, P=0.166; pooled HR =3.06, 95% CI: 1.57-5.98, I²=0.0%, P=0.860). Besides, the translational level of NAMPT was also validated by UALCAN and the Human Protein Atlas database [immunohistochemistry (IHC)].

Conclusions

Our results shed light on that NAMPT might be an oncogenic factor in breast cancer, gastric cancer and urothelial carcinoma.

The role of visfatin in cancer proliferation, angiogenesis, metastasis, drug resistance and clinical prognosis

Visfatin, also known as nicotinamide phosphoribosyltransferase or pre-B-cell colony-enhancing factor (PBEF), is an adipocytokine secreted by adipocytes, macrophages and inflamed endothelial tissue. Related reports have indicated a positive correlation between the visfatin level and obesity and cancer risk. In addition to its original function, visfatin is multifunctional and plays critical roles in the promotion of several processes relevant to cancer progression including cancer cell proliferation, angiogenesis, metastasis and drug resistance. The relative expression of visfatin and the potential visfatin receptor on a pan-cancer scale was determined based on the transcriptome analysis data in The Cancer Genome Atlas. We further show the clinical association of its signaling axis with the survival of cancer patients, which reveals its prognostic power for specific cancer types. This review illustrates visfatin’s biological functions related to cancer progression and demonstrates its clinical significance in predicting outcomes of cancer patients.

Circulating visfatin levels and cancers risk: A systematic review and meta-analysis

Visfatin levels have been reported to be abnormal in many types of cancers. However, epidemiological studies yielded inconsistent results. Therefore, a meta-analysis was performed to assess the association between circulating visfatin levels and cancer risk. A systematic search was conducted for relevant studies in health-related electronic databases up to March 2018. Data related to standard mean difference (SMD) and overall odds ratio (ORS) were collected and analyzed. Summary SMD and pooled OR with 95% CIs were calculated using a random-effect model. Funnel plot and Egger's linear regression test were conducted to examine the risk of publication bias. A total of 27 studies with 2,693 cases and 3,040 healthy controls were included in meta-analysis for pooling SMD analysis. The results of the meta-analysis showed a significant higher visfatin levels in patients with various cancers than in controls, with a pooled SMD of 0.88, 95% CI = 0.56-1.20, p = 0.000. In subgroup, metaregression, Galbraith plot, and sensitivity analysis showed no substantial difference among all the analyzed factors. Data from 14 studies were also used for pooling ORs analysis. Metaresults revealed that high visfatin levels were associated with cancer risk (OR = 1.24, 95% CI: 1.14-1.34, p = 0.000). No evidence of publication bias was observed for pooling ORs and SMD analysis. This meta-analysis indicated a significant association between high circulating visfatin levels and increased risk of various cancers. Visfatin may represent a potential biomarker for early detection of cancers who may benefit from preventive treatment.Note.

Investigating the effect of visfatin on ERalpha phosphorylation (Ser118 and Ser167) and ERE-dependent transcriptional activity

Obesity is associated with higher postmenopausal breast cancer incidence. Visfatin level alteration is one of the mechanisms by which obesity promotes cancer. Ligand-independent activation of estrogen receptor alpha (ERα) is also associated with carcinogenesis. The activity of ERα is modulated through phosphorylation on multiple sites by a number of protein kinases. Here we investigated the effect of visfatin as a novel adipocytokine on the phosphorylation and activity of ERα in MCF-7 breast cancer cells. We showed that exogenous administration of visfatin significantly increased the phosphorylation of ERα at serine 118 (Ser118) and 167 (Ser167) residues. Visfatin-induced Ser118 phosphorylation was diminished after treatment of cells with U0126 (MEK1/2 inhibitor). Furthermore, our results showed that visfatin-induced Ser167 phosphorylation is mediated through both MAPK and PI3K/Akt signaling pathways. Inhibition of the enzymatic activity of visfatin by FK866 had no effect on phosphorylation of ERα. We also showed that visfatin enhanced the estrogen response element (ERE)-dependent activity of ER in the presence of 17-β estradiol (E2). Additional study on T47D cells showed that visfatin also increased Ser118 and Ser167 phosphorylation of ERα and enhanced ERE-dependent activity in the presence of E2 in these cells.

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.

Targeting IκappaB kinases for cancer therapy

The inhibitory kappa B kinases (IKKs) and IKK related kinases are crucial regulators of the pro-inflammatory transcription factor, nuclear factor kappa B (NF-κB). The dysregulation in the activities of these kinases has been reported in several cancer types. These kinases are known to regulate survival, proliferation, invasion, angiogenesis, and metastasis of cancer cells. Thus, IKK and IKK related kinases have emerged as an attractive target for the development of cancer therapeutics. Several IKK inhibitors have been developed, few of which have advanced to the clinic. These inhibitors target IKK either directly or indirectly by modulating the activities of other signaling molecules. Some inhibitors suppress IKK activity by disrupting the protein-protein interaction in the IKK complex. The inhibition of IKK has also been shown to enhance the efficacy of conventional chemotherapeutic agents. Because IKK and NF-κB are the key components of innate immunity, suppressing IKK is associated with the risk of immune suppression. Furthermore, IKK inhibitors may hit other signaling molecules and thus may produce off-target effects. Recent studies suggest that multiple cytoplasmic and nuclear proteins distinct from NF-κB and inhibitory κB are also substrates of IKK. In this review, we discuss the utility of IKK inhibitors for cancer therapy. The limitations associated with the intervention of IKK are also discussed.

Extracellular NAMPT/Visfatin induces proliferation through ERK1/2 and AKT and inhibits apoptosis in breast cancer cells

BACKGROUND

Visfatin is a novel adipokine and proinflammatory cytokine which is implicated in breast cancer progression. The exact proliferative and anti-apoptotic mechanisms of visfatin are still under debate. In this study, the effect of extracellular visfatin on proliferation and apoptosis of breast cancer cells were investigated considering key regulatory molecules in these procedures.

METHODS

BrdU (Bromodeoxyuridine) experiment was used to assess cell proliferation in response to visfatin treatment. Cell viability and apoptosis were assessed using MTT assay and flowcytometry, respectively. Phosphorylation levels of AKT and ERK1/2 as well as survivin levels and Poly ADP ribose polymerase (PARP) cleavage were investigated by western blot analysis.

RESULTS

Visfatin induced proliferation of MCF-7 and MDA-MB-231 cells, an effect that was repressed by using AKT and ERK1/2 inhibitors, indicating involvement of these two signaling pathways in the proliferative effect of visfatin. Similarly, phosphorylation of AKT and ERK1/2 were elevated by visfatin treatment. On the other hand, visfatin improved cell viability and prevented TNF-α-induced apoptosis as well as PARP cleavage. Visfatin also exerted a protective effect on survivin.

CONCLUSION

The results of this study suggest that visfatin induces breast cancer cell proliferation through AKT/PI3K and ERK/MAPK activation and protects against apoptosis in these cells. Thus increased visfatin levels may augment breast cancer development and attenuate treatment efficiency in breast cancer patients.

Association of leptin, visfatin, apelin, resistin and adiponectin with clear cell renal cell carcinoma

Although an association between obesity and the occurrence of renal cell carcinoma (RCC) has been identified, the mechanism by which obesity functions to increase this risk of cancer remains unclear. Leptin, visfatin, apelin, resistin and adiponectin are peptide hormones secreted by adipocytes; it is considered that these may affect RCC development by exerting effects on proliferation, cell growth and inflammation. The aim of the present study was to investigate the association between the aforementioned adipokine genes and clear cell RCC (CC-RCC). The GSE6344 dataset was downloaded from the Gene Expression Omnibus database, and the relative expression levels of the adipokine genes were analyzed. To verify the results of the mRNA microarray, 77 paired samples of CC-RCC and corresponding adjacent normal tissue were allocated into two groups. The extraction of total RNA was conducted, and the mRNA expression of adipokine genes was analyzed using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The data from the GSE6344 dataset indicated that the expression of visfatin and apelin was upregulated (P<0.0001 and P<0.01, respectively), and adiponectin was downregulated (P<0.001) in the CC-RCC tissues compared with the adjacent normal tissues. The data from RT-qPCR demonstrated that visfatin and resistin gene expression was increased (P<0.01 and P<0.05, respectively) in the CC-RCC tissues. Furthermore, the mRNA expression level of leptin and adiponectin in the adjacent normal tissue was higher than those in the cancer tissue (P<0.01). The current study verifies that visfatin and adiponectin are associated with an increased risk of CC-RCC, which presents further insights into the molecular mechanisms of CC-RCC tumorigenesis.

Visfatin Triggers the Cell Motility of Non-Small Cell Lung Cancer via Up-Regulation of Matrix Metalloproteinases

High levels of visfatin are correlated with worse clinical prognosis of various cancers. Still, the effects and mechanisms of visfatin on progression of non-small cell lung cancer (NSCLC) remain unclear. This study revealed that plasma levels of visfatin in patients with NSCLC (585 ± 287 pg/ml) were significantly (p < 0.01) higher than those in healthy people (142 ± 61.1 pg/ml). The high level of plasma visfatin was found to be significantly (p < 0.05) correlated with TNM stage, lymph node metastasis and distant metastasis. Visfatin treatment can increase the migration and invasion of NSCLC cells via up-regulation of metalloproteinase-2 (MMP-2) and MMP-9. Both si-MMP-2 and si-MMP-9 attenuated visfatin-induced migration of NSCLC cells. The inhibitor of NF-κB, while not ERK1/2, p38-MAPK or PI3K/Akt, can significantly abolish visfatin-induced migration of A549 cells and up-regulation of MMP-2 and MMP-9. Furthermore, visfatin can increase the phosphorylation of IκBα and p65 and the transcription activities of NF-κB in NSCLC cells. ACHP, the inhibitor of IKK-β, blocked visfatin-induced activation of p65 and up-regulation of MMP-2 and MMP-9. Collectively, our data revealed that visfatin can trigger the in vitro migration and invasion of NSCLC cells via up-regulation of MMPs through activation of NF-κB.

Extracellular nicotinamide phosphoribosyltransferase, a new cancer metabokine

In this review, we focus on the secreted form of nicotinamide phosphoribosyltransferase (NAMPT); extracellular NAMPT (eNAMPT), also known as pre-B cell colony-enhancing factor or visfatin. Although intracellular NAMPT is a key enzyme in controlling NAD metabolism, eNAMPT has been reported to function as a cytokine, with many roles in physiology and pathology. Circulating eNAMPT has been associated with several metabolic and inflammatory disorders, including cancer. Because cytokines produced in the tumour micro-environment play an important role in cancer pathogenesis, in part by reprogramming cellular metabolism, future improvements in cancer immunotherapy will require a better understanding of the crosstalk between cytokine action and tumour biology. In this review, the knowledge of eNAMPT in cancer will be discussed, focusing on its immunometabolic function as a metabokine, its secretion, its mechanism of action and possible roles in the cancer micro-environment.

Visfatin is involved in promotion of colorectal carcinoma malignancy through an inducing EMT mechanism

Increasing evidences suggested visfatin, a newly discovered obesity-induced adipocytokine, is involved in promotion of cancer malignancy and correlated with worse clinical prognosis. While its effects and mechanisms on progression of colorectal cancer (CRC) remain unclear. Our clinical data show that visfatin protein is over expressed, positive associated with lymph node metastasis, high-grade tumor, and poor prognosis in 87 CRC patients. The levels of plasma visfatin are significantly upregulated in Stage IV colon cancer. Visfatin can significantly promote the in vitro migration and invasion of CRC cells via induction epithelial mesenchymal transition (EMT). It can increase the expression and nuclear translocation of Snail, a key transcription factor in regulating EMT. While silencing of Snail attenuates visfatin induced EMT. Further studies reveal visfatin can inhibit the association of Snail with GSK-3β and subsequently suppress ubiquitylation of Snail. In addition, visfatin can increase the expression and nuclear translocation of β-catenin, elevate its binding with Snail promoter, and then increase the transcription of Snail. While inhibitor of PI3K/Akt, LY294002, abolishes visfatin induced up regulation of Snail, Vimentin (Vim), β-catenin, and phosphorylated GSK-3β. In summary, our data suggest that increased expression of visfatin are associated with a more aggressive phenotype of CRC patients. It can trigger the EMT of CRC cells via Akt/GSK-3β/β-catenin signals.

Extracellular Visfatin-Promoted Malignant Behavior in Breast Cancer Is Mediated Through c-Abl and STAT3 Activation

PURPOSE

Visfatin is an adipocytokine involved in cellular metabolism, inflammation, and cancer. This study investigated the roles of extracellular visfatin in breast cancer, and explored underlying mechanisms in clinical and experimental settings.

EXPERIMENTAL DESIGN

Associations of serum visfatin with clinicopathologic characteristics and patient survival were assessed with Cox regression models and Kaplan-Meier analyses. Effects of extracellular visfatin on cultured breast cancer cells were examined, followed by in vivo investigation of tumor growth and metastasis in xenograft animal models. Imatinib and Stattic were used to inhibit c-Abl and STAT3 activation, respectively.

RESULTS

Breast cancer patients with high serum visfatin levels were associated with advanced tumor stage, increased tumor size and lymph node metastasis, and poor survival. Elevated phosphorylation of c-Abl and STAT3 in breast tumor tissues were correlated with high serum visfatin levels in patients. Visfatin-promoted in vitro cell viability and metastatic capability were suppressed by imatinib (c-Abl inhibitor) and Stattic (STAT3 inhibitor). Increased in vivo cell invasiveness was observed in zebrafish xenografted with visfatin-pretreated breast cancer cells. Tumor growth and lung metastasis occurred in visfatin-administered mice xenografted with breast cancer cells. Tail vein-injected mice with visfatin-pretreated breast cancer cells showed increased lung metastasis, which was suppressed by imatinib.

CONCLUSIONS

Serum visfatin levels in breast cancer patients reveal potential prognostic values, and our findings that visfatin promoted breast cancer through activation of c-Abl and STAT3 may provide an important molecular basis for future design of targeted therapies that take into account different serum visfatin levels in breast cancer. Clin Cancer Res; 22(17); 4478-90. ©2016 AACR.

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.

Regulative Effect of Nampt on Tumor Progression and Cell Viability in Human Colorectal Cancer

Colorectal cancer (CRC) is the third most common cancer disease. Here we examined Nampt expression in patients with CRC and the effect of Nampt on cell viability in CRC cells. Nampt protein was overexpressed in colorectal adenoma as well as colorectal carcinoma. The immunoreactive staining of Nampt was negative in the adjacent normal colorectal tissue, weak in colorectal adenoma, and strong in colorectal carcinoma, which may represent tumor progression. Further evaluation of clinical data showed that Nampt expression was not correlated with the clinicopathological characteristics of CRC. Additionally, our in vitro studies demonstrated that Nampt promotes CRC cell viability, whereas the Nampt inhibitor FK866 suppressed CRC cell viability, which was in concordance with the previous studies in other cancer cells. Treatment with Nampt-siRNA reduced the Nampt protein expression resulting in the inhibition of the cell viability of HCT116 and Caco2. Thus, the involvement of Nampt in cell growth indicates that Nampt may play an important role in colorectal tumorigenesis. As a consequence, our results suggest that Nampt may be considered as a progression marker of colorectal tumor and a potentially therapeutic target for the treatment of CRC.

Elevated plasma visfatin levels correlate with poor prognosis of gastric cancer patients

Visfatin is a proinflammmatory cytokine with accumulating evidence for its rise in circulation of cancer patients. This study aimed to evaluate the relationship between preoperative plasma visfatin level and prognosis of gastric cancers. Preoperative plasma visfatin levels of 262 patients with gastric cancers and plasma visfatin levels of 262 healthy individuals were determined using enzyme-linked immunosorbent assay. Preoperative plasma visfatin level was substantially higher in patients than in healthy subjects. Plasma visfatin levels were associated with invasion depth, lymph node metastasis, distant metastasis, peritoneal dissemination, tumor size and tumor node metastasis stage. Multivariate analysis revealed that high plasma visfatin level was an independent factor for death. Receiver operating characteristic curve analysis showed that plasma visfatin level predicted death with high area under curve. Multivariate Cox regression analysis identified plasma visfatin level as an independent predictor of overall survival. Thus, our results suggest that high preoperative plasma visfatin level is associated with prognostic factors for gastric cancer as well as may play a role as prognostic biomarker in gastric cancer survival.