Increased adiponectin associated with poor survival in hepatocellular carcinoma

The adipokines in oral cancer pathogenesis and its potential as a new therapeutic approach

The involvement of adipose tissue in the development of cancer is currently the subject of an increasing number of research due to the growing relevance of lipid metabolism in tumor growth. Obesity influences the tumor immune microenvironment (TME) in oral cancer. Visceral white adipose tissue (WAT) consists of adipocytes, connective tissue, immune cells, and stromovascular cells. The metabolic processes of immune cells within the adipose tissue of individuals with obesity predominantly depend on oxidative phosphorylation (intrinsically) and are characterized by elevated levels of M2 macrophages, Treg cells, Th2 cells, and eosinophils from an extrinsic perspective. The adipokines secreted by adipocytes facilitate communication with adjacent tissues to regulate glucose and lipid metabolism. Obesity influences cancer progression through the dysregulation of adipocytokines, characterized by an augmented synthesis of the oncogenic adipokine leptin, coupled with a reduced secretion of adiponectin. Under standard physiological settings, these adipokines fulfill essential roles in sustaining homeostasis. This review analyzed the influence of adipocytes on oral cancer by detailing the mediators released by adipocytes. Comprehending the molecular foundations of the protumor roles of adipokines in oral cancers might provide novel treatment targets.

Reappraisal of the Roles of the Sonic Hedgehog Signaling Pathway in Hepatocellular Carcinoma

HCC remains one of the leading causes of cancer-related death globally. The main challenges in treatments of hepatocellular carcinoma (HCC) primarily arise from high rates of postoperative recurrence and the limited efficacy in treating advanced-stage patients. Various signaling pathways involved in HCC have been reported. Among them, the Sonic hedgehog (SHH) signaling pathway is crucial. The presence of SHH ligands is identified in approximately 60% of HCC tumor tissues, including tumor nests. PTCH-1 and GLI-1 are detected in more than half of HCC tissues, while GLI-2 is found in over 84% of HCC tissues. The SHH signaling pathway (including canonical and non-canonical) is involved in different aspects of HCC, including hepatocarcinogenesis, tumor growth, tumor invasiveness, progression, and migration. The SHH signaling pathway also contributes to recurrence, metastasis, modulation of the cancer microenvironment, and sustaining cancer stem cells. It also affects the resistance of HCC cells to chemotherapy, target therapy, and radiotherapy. Reappraisal of the roles of the SHH signaling pathway in HCC may trigger some novel therapies for HCC.

Tumor Necrosis Factor-Alpha and Adiponectin in Nonalcoholic Fatty Liver Disease-Associated Hepatocellular Carcinoma

Nonalcoholic fatty liver disease (NAFLD) is emerging as an important risk factor for hepatocellular carcinoma (HCC), whose prevalence is rising. Although the mechanisms of progression from NAFLD to HCC are not fully elucidated, tumor necrosis factor-α (TNF-α) and adiponectin, as well as their interplay, which seems to be antagonistic, may contribute to the pathophysiology of NAFLD-associated HCC. TNF-α initially aims to protect against hepatocarcinogenesis, but during the progression of NAFLD, TNF-α is increased, thus probably inducing hepatocarcinogenesis in the long-term, when NAFLD is not resolved. On the other hand, adiponectin, which is expected to exert anti-tumorigenic effects, is decreased during the progression of the disease, a trend that may favor hepatocarcinogenesis, but is paradoxically increased at end stage disease, i.e., cirrhosis and HCC. These observations render TNF-α and adiponectin as potentially diagnostic biomarkers and appealing therapeutic targets in the setting of NAFLD-associated HCC, possibly in combination with systematic therapy. In this regard, combination strategy, including immune checkpoint inhibitors (ICIs) with anti-TNF biologics and/or adiponectin analogs or medications that increase endogenous adiponectin, may warrant investigation against NAFLD-associated HCC. This review aims to summarize evidence on the association between TNF-α and adiponectin with NAFLD-associated HCC, based on experimental and clinical studies, and to discuss relevant potential therapeutic considerations.

Oxidative stress and Liver X Receptor agonist induce hepatocellular carcinoma in Non-alcoholic steatohepatitis model

BACKGROUND AND AIM

The incidence of non-alcoholic steatohepatitis (NASH)-related hepatocellular carcinoma (HCC) is progressively increasing. However, the pathophysiology and etiology of NASH progression to HCC are unknown. We hypothesized that steatosis was the key factor in NASH-related hepatocarcinogenesis and aimed to evaluate the effects of long-term liver X receptor (LXR) agonist stimulation on hepatic steatosis induced by a high-fat diet and oxidative stress.

METHODS

We used an LXR agonist (T0901317) and CCl4 to induce hepatic steatosis and oxidative stress, respectively. C57BL/6 mice fed with a high-fat diet were treated with either T0901317 + CCl4 (T09 + CCl4 group) or CCl4 alone (CCl4 group). T0901317 (2.5 mg/kg) and CCl4 (0.1 mL/kg) were intraperitoneally administered twice weekly for 24 weeks.

RESULTS

The liver-to-body weight ratio was significantly higher in the T09 + CCl4 group than in the CCl4 group. Mice in the T09 + CCl4 group exhibited abnormal lipid metabolism and NASH-like histopathological features. Additionally, all mice in the T09 + CCl4 group developed liver tumors diagnosed as well-differentiated HCC. The genes identified via microarray analysis were related to NASH and HCC development.

CONCLUSIONS

By combining long-term LXR agonist stimulation with oxidative stress and a high-fat diet, we successfully reproduced liver conditions in mice similar to those in humans with NASH and progression to HCC. Our results provide new insight into NASH-related HCC progression and therapy.

The association of leptin and adiponectin with hepatocellular carcinoma risk and prognosis: a combination of traditional, survival, and dose-response meta-analysis

Background

An increasing number of studies have focused on the association between leptin, adiponectin levels and the risk as well as the prognosis of hepatocellular carcinoma. However, the reported results are conflicting.

Methods

A meta-analysis was performed to assess the correlation between leptin, adiponectin levels and risk and prognosis of hepatocellular carcinoma (CRD42020195882). Through June 14, 2020, PubMed, Cochrane Library and EMBASE databases were searched, including references of qualifying articles. Titles, abstracts, and main texts were reviewed by at least 2 independent readers. Stata 16.0 was used to calculate statistical data.

Results

Thirty studies were included in this meta-analysis and results showed that hepatocellular carcinoma group had significantly higher leptin levels than the cancer-free control group (SMD = 1.83, 95% CI (1.09, 2.58), P = 0.000), the healthy control group (SMD = 4.32, 95% CI (2.41, 6.24), P = 0.000) and the cirrhosis group (SMD = 1.85, 95% CI (0.70, 3.01), P = 0.002). Hepatocellular carcinoma group had significantly higher adiponectin levels than the healthy control group (SMD = 1.57, 95% CI (0.37, 2.76), P = 0.010), but no statistical difference compared with the cancer-free control group (SMD = 0.24, 95% CI (− 0.35, 0.82), P = 0.430) and the cirrhosis group (SMD = − 0.51, 95% CI (− 1.30, 0.29), P = 0.213). The leptin rs7799039 polymorphism was associated with increased risk of hepatocellular carcinoma (G vs A: OR = 1.28, 95% CI (1.10, 1.48), P = 0.002). There were linear relationships between adiponectin levels and the risk of hepatocellular carcinoma (OR = 1.066, 95% CI (1.03, 1.11), P = 0.001). In addition, the results showed that high/positive expression of adiponectin was significantly related to lower overall survival in hepatocellular carcinoma patients (HR = 1.70, 95% CI (1.22, 2.37), P = 0.002); however, there was no significantly association between the leptin levels and overall survival (HR = 0.92, 95% CI (0.53, 1.59), P = 0.766).

Conclusion

The study shows that high leptin levels were associated with a higher risk of hepatocellular carcinoma. Adiponectin levels were proportional to hepatocellular carcinoma risk, and were related to the poor prognosis.

Data on Adiponectin from 2010 to 2020: Therapeutic Target and Prognostic Factor for Liver Diseases?

The review describes the role of adiponectin in liver diseases in the presence and absence of surgery reported in the literature in the last ten years. The most updated therapeutic strategies based on the regulation of adiponectin including pharmacological and surgical interventions and adiponectin knockout rodents, as well as some of the scientific controversies in this field, are described. Whether adiponectin could be a potential therapeutic target for the treatment of liver diseases and patients submitted to hepatic resection or liver transplantation are discussed. Furthermore, preclinical and clinical data on the mechanism of action of adiponectin in different liver diseases (nonalcoholic fatty disease, alcoholic liver disease, nonalcoholic steatohepatitis, liver cirrhosis and hepatocellular carcinoma) in the absence or presence of surgery are evaluated in order to establish potential targets that might be useful for the treatment of liver disease as well as in the practice of liver surgery associated with the hepatic resections of tumors and liver transplantation.

Fatty changes associated with N-Nitrosodiethylamine (DEN) induced hepatocellular carcinoma: a role of sonic hedgehog signaling pathway

Backgrounds and Aims: Hepatocellular Carcinoma (HCC) is the leading cause of cancer-related mortality across the world. Non-viral etiological factors including obesity and metabolic syndrome have now become prevalent cause of hepatocellular carcinoma. Sonic Hedgehog (SHH) pathway is activated in hepatocellular carcinoma but its role in regulation of lipogenic molecules during the hepatocarcinogenesis is not known. The aim of present study is to explore the role of SHH pathway in fatty changes associated with hepatocarcinogenesis at different stages and to further correlate the expression of SHH with lipogenic pathways.

Results: Our results demonstrated significant increase in lipidosis and fibrosis in DEN+CCl4 treated animals. It was simultaneously associated with the enhanced expression level of SHH, E2F1, adiponectin, and lipogenic molecules in DEN+CCl4 treated animals. These results were also corroborated with the similar findings in higher stage patients’ biospecimens.

Methods: N-Nitrosodiethylamine (DEN) and Carbon TetraChloride (CCl4) induced hepatocellular acrcinoma model in male Wistar rats were established to study the expression level of SHH pathway and associated fatty changes during different stages of hepatocarcinogenesis. The expression levels of SHH, E2F1, and lipogenic molecules were checked at different stages of hepatocellular carcinoma. These results were further compared with biospecimens of hepatocellular carcinoma patients of different stages.

Conclusions: Our results revealed an unknown aspect of SHH pathway in hepatocarcinogenesis via its control over lipogenesis. It gives insight into the lipogenic properties of DEN+CCl4 induced rodent hepatocarcinogenesis model and how SHH pathway operate to arbitrate this response.

The Possible Role of Adipokines in HCV Associated Hepatocellular Carcinoma

Background:

Adipokines play an important role in the regulation of inflammation and tumor progression.

Aim:

Assessment of the possible role of adiponectin, leptin and visfatin in HCV associated hepatocellular carcinoma (HCC).

Methods:

patients were classified into 85 patients with HCV associated HCC, 100 patients with chronic hepatitis C viral (HCV) infection compared to 50 normal control (NC) subjects. All subjects included in the study were assessed for HCV infection by seropositive HCV antibodies, as well as HCV RNA by RT-PCR. Serum levels of adiponectin, leptin and visfatin were assessed using enzyme linked immunosorbent assay (ELISA). The data were correlated to the relevant clinic-pathological features of the patients, and the overall survival (OS) rate.

Results:

There was a significant difference in the serum levels of adiponectin and visfatin among HCC, HCV and NC groups (P<0.001). The serum levels of leptin and alpha fetoprotein (AFP) were significantly higher in HCC group (P<0.001). There was a significant association between the serum level of adiponectin and advanced Child class liver cirrhosis (P=0.03), as well as with poor performance status (ECOG, P=0.02). Serum leptin associated significantly with the number of lesions in the liver (P=0.006), visfatin associated with increased mortality rate (P<0.001). Adiponectin, leptin and visfatin associated significantly with liver cirrhosis in HCV patients (P<0.01). Leptin achieved the highest sensitivity (98.8%). visfatin achieved the highest specificity (100%) and PPV (100%) for detection of HCC. The combination of serum leptin and visfatin for the diagnosis of HCV associated HCC showed sensitivity, specificity, PPV, NPV and accuracy (100%, 96.6%, 93.4%, 100% and 97.4%; respectively).

Conclusion:

Adiponectin, leptin and visfatin have an important role(s) in the pathogenesis of HCV associated HCC.

Remodeling the Microenvironment before Occurrence and Metastasis of Cancer

Tumorigenesis and progression of cancer are complex processes which transformed cells and stromal cells interact and co-evolve. Intrinsic and extrinsic factors cause the mutations of cells. The survival of transformed cells critically depends on the circumstances which they reside. The malignant transformed cancer cells reprogram the microenvironment locally and systemically. The formation of premetastatic niche in the secondary organs facilitates cancer cells survival in the distant organs. This review outlines the current understanding of the key roles of premalignant niche and premetastatic niche in cancer progression. We proposed that a niche facilitates survival of transformed cells is characteristics of senescence, stromal fibrosis and obese microenvironment. We also proposed the formation of premetastatic niche in secondary organs is critically influenced by primary cancer cells. Therefore, it suggested that strategies to target the niche can be promising approach to eradicate cancer cells.

Diabetes and hepatocellular carcinoma: A pathophysiological link and pharmacological management

Both diabetes mellitus (DM) and cancer are multifarious, dissimilar, and long-lasting, fatal diseases with a remarkable influence on health worldwide. DM is not only related to cardiovascular diseases, neuropathy, nephropathy, and retinopathy, but also related to a number of liver diseases such as nonalcoholic fatty liver disease, steatohepatitis, and liver cirrhosis. Recently, it is hypothesized that DM has a greater risk for many forms of cancer, such as breast, colorectal, endometrial, pancreatic, gallbladder, renal, and liver cancer including hepatocellular carcinoma (HCC). Both DM and cancer have many common risk factors, but the association between these two is poorly stated. Several epidemiologic studies have revealed the association between pathogenic and prognostic characteristics of DM and a higher incidence of HCC, thus representing DM as an independent risk factor for HCC development. The etiological and pathophysiological relationship between DM and HCC has been presented in this review by linking hyperglycemia, hyperinsulinemia, insulin resistance, and activation of insulin-like growth factor signaling pathways and pharmacological management of HCC associated with DM.

Dual-therapy strategy for modification of adiponectin receptor signaling in aging-associated chronic diseases

Given the paradigm of anti-insulin resistance in therapies for metabolic syndrome, there has been considerable interest in adiponectin (APN), an adipocyte-derived sensitizer of insulin receptor signaling. In contrast to hypoadiponectinemia in metabolic syndrome, evidence suggests that Alzheimer's disease (AD) and other diseases, including chronic heart failure (CHF) and chronic kidney disease (CKD), are characterized by hyperadiponectinemia as well as the APN/obesity paradoxes, indicating that a decrease in APN might also be beneficial for these diseases. Thus, distinct from metabolic syndrome, it is anticipated that APN receptor antagonists rather than agonists might be effective in therapy for some chronic diseases.

Pre-diagnostic biomarkers of metabolic dysregulation and cancer mortality

INTRODUCTION

The obesogenic milieu is a pro-tumorigenic environment that promotes tumor initiation, angiogenesis and metastasis. In this prospective cohort, we examined the association between pre-diagnostic metabolic biomarkers, plasma adiponectin, resistin, leptin and lipoprotein (a), and the risk of cancer mortality.

METHODS

Prospective data was obtained from the REasons for Geographic and Racial Differences in Stroke (REGARDS) cohort of Blacks and Whites followed from 2003 through 2012 for cancer mortality. We determined the association between metabolism biomarkers (log-transformed and tertiles) and risk of cancer mortality using Cox Proportional Hazards models with robust sandwich estimators to calculate the 95% confidence intervals (CIs), and adjusted for baseline covariates, including age, gender, income, education, physical activity, BMI, smoking status, alcohol use, and comorbidity score.

RESULTS

Among 1764 participants with available biomarker data, each SD higher log-leptin was associated with a 54% reduced risk of total cancer mortality (HR: 0.46, 95% CI: 0.23 – 0.92) and obesity-related cancer mortality (HR: 0.55, 95% CI: 0.39-0.79). Among Blacks only, each SD higher log-resistin was associated with a nearly 7-fold increased risk of cancer mortality (adjusted HR: 6.68, 95% CI: 2.10 – 21.21). There were no significant associations of adiponectin or Lp(a) and cancer mortality.

CONCLUSIONS

Leptin is involved in long-term regulation of energy balance, while resistin is involved in chronic inflammation and LDL production. These findings highlight the biological mechanisms linking metabolic dysregulation with cancer mortality, and the influence of resistin on cancer mortality only among Blacks suggests that this hormone may be a useful biomarker of racial differences in cancer mortality that deserves further study.

IMPACT

Our observed increased risk of cancer mortality associated with higher serum resistin levels among Blacks suggests that if validated in larger cohorts, clinical strategies focused on resistin control may be a promising cancer prevention strategy.

Ubenimex, an APN inhibitor, could serve as an anti‑tumor drug in RT112 and 5637 cells by operating in an Akt‑associated manner

Bladder cancer, a common urinary tract tumor, has high mortality and recurrence rates associated with metastasis. Aminopeptidase N (APN) expression and metastasis have been indicated to be associated with one another. Ubenimex may function as an APN inhibitor to inhibit the degradation of the extracellular matrix during tumorigenesis. Furthermore, APN has been widely used as an adjuvant therapy for the treatment of tumors; however, little information is available regarding the impact of ubenimex on patients. Autophagy is suggested to be important in the transformation and progression of cancer. Additionally, apoptosis, which leads to the rapid demolition of cellular organelles and structures, has also been suggested as an important factor. Thus, the present study investigated the role of ubenimex in inhibiting migration and invasion by downregulating APN expression levels to induce autophagic cell death and apoptosis in bladder cancer cells. RT112 and 5637 cell lines were treated with varying doses of ubenimex. Cell viability was measured by CCK8 colorimetry and flow cytometry. Using fluorescence microscopy, autophagic cell death was assessed using acridine orange/ethidium bromide staining. Furthermore, apoptotic cell death was assessed using flow cytometry and Trypan blue staining was used to evaluate the cell death rate. Protein expression was determined by western blot analysis. Matrigel invasion assays were exploited to assess the invasion capabilities of 5637 cells. Wound-healing migration assays and Matrigel migration assays were exploited to assess the migratory abilities of 5637 cells. Treatment with ubenimex was accompanied by decreased Akt expression, indicating that ubenimex may have similar functions to Akt inhibitors. Results also indicated that ubenimex inhibited cell migration and invasion in bladder cancer cells. Furthermore, ubenimex also induced autophagic cell death and apoptosis, which suggested that mixed programmed cell death occurred in ubenimex-treated bladder cancer cells. The results from the present study suggest that ubenimex may be a potential adjuvant therapy for the treatment of bladder cancer.

Plasma Adiponectin and Hepatocellular Carcinoma Survival Among Patients Without Liver Transplantation

AIM

To investigate the levels of leptin and adiponectin in prediction of hepatocellular carcinoma (HCC) survival among patients without liver transplantation.

MATERIALS AND METHODS

We measured pretreatment plasma leptin and adiponectin in 172 HCC cases who were prospectively followed-up over 7 years.

RESULTS

Gender, hepatitis B virus (HBV) and hepatitis C virus (HCV) infection, high body mass index (BMI), diabetes mellitus (DM) history and Child-Pugh (CP) class were associated with leptin and adiponectin levels, while α-fetoprotein (AFP) and presence of metastasis, being outside the Milan criteria and Barcelona clinic liver cancer (BCLC) stage, were significantly associated with liver transplantation and HCC survival. No significant association was observed for leptin or adiponectin and HCC survival in the overall group. In subgroup analyses among those without liver transplantation, we found significant associations between metastasis, Milan criteria, BCLC stage, hepatitis B surface antigen (HBsAg) and HCC survival. When separately determining the Cox proportional hazard models and Kaplan-Meier survival curves by liver transplantation status, higher adiponectin was significantly associated with an increased hazard ratio (HR) of death of 1.72 (95% confidence interval (CI)=1.12-2.64), i.e. poor survival among patients without liver transplantation. A multivariate Cox proportional hazard model, including adiponectin, CP class, presence of metastasis, tumor outside of Milan criteria, AFP and BCLC stage B/C parameters, also showed significant association with poor HCC survival (likelihood ratio test p<0.0001). No significant impact was observed for leptin on HCC survival regardless of liver transplantation status.

CONCLUSION

Higher levels of plasma adiponectin may predict poor HCC survival among patients without liver transplantation.

Evolving role of adiponectin in cancer-controversies and update

Adiponectin (APN), an adipokine produced by adipocytes, has been shown to have a critical role in the pathogenesis of obesity-associated malignancies. Through its receptor interactions, APN may exert its anti-carcinogenic effects including regulating cell survival, apoptosis and metastasis via a plethora of signalling pathways. Despite the strong evidence supporting this notion, some work may indicate otherwise. Our review addresses all controversies critically. On the whole, hypoadiponectinaemia is associated with increased risk of several malignancies and poor prognosis. In addition, various genetic polymorphisms may predispose individuals to increased risk of obesity-associated malignancies. We also provide an updated summary on therapeutic interventions to increase APN levels that are of key interest in this field. To date efforts to manipulate APN levels have been promising, but much work remains to be done.

Adiponectin is associated with poor prognosis in carcinoma patients: evidence from a meta-analysis

Background

Studies have come to conflicting conclusions about whether adiponectin (APN) expression is associated with cancer prognosis. To help resolve this question, we meta-analyzed the available evidence.

Methods

PubMed, EMBASE, the Cochrane Library, the Chinese Biological Medical Database and the Chinese National Knowledge Infrastructure Database were systematically searched to identify all eligible studies examining APN expression and prognosis for patients with any type of cancer. Pooled hazard ratios (HRs) and corresponding 95 % confidence intervals (CIs) related to overall survival (OS) or disease-free survival (DFS) were calculated.

Results

Ten studies involving 999 patients were meta-analyzed. Analysis across all patients revealed no significant association between high/positive APN expression and DFS, but they did show a significant association between high/positive APN expression and OS (HR 1.51, 95 %CI 1.21 to 1.89). Subgroup analysis showed that high/positive APN expression in non-Asians was significantly associated with both DFS (HR 1.36, 95 % CI 1.03 to 1.80) and OS (HR 1.53, 95 %CI 1.20 to 1.96), but no such associations were observed in Asians. In addition, high/positive APN expression was significantly associated with OS across all patients with hepatocellular carcinoma (HR 1.89, 95 %CI 1.20 to 2.98).

Conclusions

The available evidence suggests that high/positive APN expression is associated with poor prognosis for patients with various carcinomas, especially for non-Asian cancer patients and for all patients with hepatocellular carcinoma. These findings should be confirmed and extended in large, well-designed studies.

Adiponectin induces apoptosis in hepatocellular carcinoma through differential modulation of thioredoxin proteins

Adiponectin blocks hepatocellular carcinoma (HCC) progression by inducing cell apoptosis through the modulation of C-Jun N-terminal kinase and mammalian target of rapamycin. However, the precise upstream signaling pathways or molecules remain elusive. In the present study, we analyzed the role of antioxidant protein thioredoxin (Trx) in adiponectin-induced apoptosis in HCC. Adiponectin treatment decreased the viabilities of both HepG2 and Huh7 HCC cells accompanied by increased accumulation of intracellular reactive oxygen species, as evidenced by 2',7'-dichlorodihydrofluorescein diacetate staining. Pretreatment of these cells with the deoxidant N-acetylcysteine blocked the inhibitory effect of adiponectin. Levels of Trx2 protein in both HCC cells were significantly decreased, and the level of Trx1 was significantly inhibited in Huh7 cells while unchanged in HepG2 cells. However, the redox state of Trx1 was altered from reduced to the oxidized form following adiponectin treatment in HepG2 cells. Overexpression of both Trx proteins rescued adiponectin-induced cell apoptosis, whereas mutated Trx proteins were less effective. Further analysis suggested that both ASK1 and JNK signaling are involved in this process. Trx1 and Trx2 proteins also manifested protective effects on HCC cells in response to adiponectin treatment in a xenograft tumor model. Furthermore, high levels of Trx proteins and low adiponectin expression levels were found in primary human HCC samples compared with paracancerous tissues. These results suggest that Trx proteins play important roles in mediating adiponectin-induced HCC cell apoptosis, thus providing new insights into the pathogenesis of HCC and identifying adiponectin and Trx proteins as potential combinational therapeutic targets for the treatment of HCC.

Serum adiponectin levels may be associated with the pathogenesis of hepatocellular carcinoma

The aim of the meta-analysis described below was to investigate the correlation between serum levels of adiponectin (ADPN) and the pathogenesis of hepatocellular carcinoma (HCC). Relevant studies about serum ADPN levels and the pathogenesis of HCC were identified by searching electric databases and by manual search. The included studies were selected in strict accordance with the inclusion and exclusion criteria. Detailed criteria were described in "Materials and methods" section. Statistical analyses were conducted with the STATA 12.0 statistical software (StataCorp, College Station, TX, USA). A total of nine studies were incorporated into this meta-analysis after careful consideration, including 705 HCC patients and 1390 healthy controls. This meta-analysis demonstrated that the serum ADPN levels in HCC patients were significantly higher than those in healthy controls (standard mean difference (SMD) = 0.97, 95% confidence intervals (CI) = 0.02∼1.93, P < 0.05). The result of subgroup analysis by ethnicity revealed that serum ADPN levels in Caucasians and Asians were both obviously higher than those in healthy controls (Caucasians: SMD = 0.51, 95% CI = 0.30∼0.73, P < 0.001; Asians: SMD = 0.49, 95% CI = 0.06∼0.91, P < 0.05), but in Africans, the differences between HCC patients and controls had no statistical significance (SMD = 2.64, 95% CI = -3.01∼8.30, P = 0.36). The evidence obtained by this meta-analysis suggests that serum ADPN levels are associated with the pathogenesis of HCC. Further conclusion might be that increased serum levels of ADPN can inhibit tumor growth and play a protective role in the development of HCC.

Serum adiponectin is associated with worsened overall survival in a prospective cohort of hepatocellular carcinoma patients

BACKGROUND

Hepatocellular carcinoma (HCC) is the third leading cause of cancer deaths worldwide. The rise in metabolic syndrome has contributed to this trend. Adipokines, such as adiponectin, are associated with prognosis in several cancers, but have not been well studied in HCC.

METHODS

We prospectively enrolled 140 patients with newly diagnosed or recurrent HCC with Child-Pugh (CP) class A or B cirrhosis. We examined associations between serum adipokines, clinicopathological features of HCC, and time to death. We also examined a subset of tumors with available pathology for tissue adiponectin receptor (AR) expression by immunohistochemistry.

RESULTS

The median age of subjects was 62 years; 79% were men, 59% had underlying hepatitis C, and 36% were diabetic. Adiponectin remained a significant predictor of time to death (hazard ratio 1.90; 95% confidence interval 1.05-3.45; p = 0.03) in a multivariable adjusted model that included age, alcohol history, CP class, stage, and serum α-fetoprotein level. Cytoplasmic AR expression (AR1 and AR2) in tumors trended higher in those with higher serum adiponectin levels and in those with diabetes mellitus, but the association was not statistically significant.

CONCLUSIONS

In this hypothesis-generating study, we found the serum adiponectin level to be an independent predictor of overall survival in a diverse cohort of HCC patients.

IMPACT

Understanding how adipokines affect the HCC outcome may help develop novel treatment and prevention strategies.