Plasma MIC-1 correlates with systemic inflammation but is not an independent determinant of nutritional status or survival in oesophago-gastric cancer

Mitochondrial dysfunction decreases cisplatin sensitivity in gastric cancer cells through upregulation of integrated stress response and mitokine GDF15

Gastric neoplasm is a high-mortality cancer worldwide. Chemoresistance is the obstacle against gastric cancer treatment. Mitochondrial dysfunction has been observed to promote malignant progression. However, the underlying mechanism is still unclear. The mitokine growth differentiation factor 15 (GDF15) is a significant biomarker for mitochondrial disorder and is activated by the integrated stress response (ISR) pathway. The serum level of GDF15 was found to be correlated with the poor prognosis of gastric cancer patients. In this study, we found that high GDF15 protein expression might increase disease recurrence in adjuvant chemotherapy-treated gastric cancer patients. Moreover, treatment with mitochondrial inhibitors, especially oligomycin (a complex V inhibitor) and salubrinal (an ISR activator), respectively, was found to upregulate GDF15 and enhance cisplatin insensitivity of human gastric cancer cells. Mechanistically, it was found that the activating transcription factor 4-C/EBP homologous protein pathway has a crucial function in the heightened manifestation of GDF15. In addition, reactive oxygen species-activated general control nonderepressible 2 mediates the oligomycin-induced ISR, and upregulates GDF15. The GDF15-glial cell-derived neurotrophic factor family receptor a-like-ISR-cystine/glutamate transporter-enhanced glutathione production was found to be involved in cisplatin resistance. These results suggest that mitochondrial dysfunction might enhance cisplatin insensitivity through GDF15 upregulation, and targeting mitokine GDF15-ISR regulation might be a strategy against cisplatin resistance of gastric cancer.

The prognostic impact of pre-treatment cachexia in resectional surgery for oesophagogastric cancer: a meta-analysis and meta-regression

BACKGROUND

Cancer cachexia is not purely an end-stage phenomenon and can influence the outcomes of patients with potentially curable disease. This review examines the effect of pre-treatment cachexia on overall survival, in patients undergoing surgical resection of oesophagogastric cancer.

METHODS

A systematic literature search of MEDLINE, EMBASE and Cochrane Library databases was conducted, from January 2000 to May 2022, to identify studies reporting the influence of cachexia on patients undergoing an oesophagogastric resection for cancer with curative intent. Meta-analyses of the primary (overall survival) and secondary (disease-free survival and postoperative mortality) outcomes were performed using random-effects modelling. Meta-regression was used to examine disease stage as a potential confounder.

RESULTS

Ten non-randomized studies, comprising 7186 patients, were eligible for inclusion. The prevalence of pre-treatment cachexia was 35 per cent (95 per cent c.i.: 24-47 per cent). Pooled adjusted hazard ratios showed that cachexia was adversely associated with overall survival (HR 1.46, 95 per cent c.i.: 1.31-1.60, P < 0.001). Meta-analysis of proportions identified decreased overall survival at 1-, 3- and 5-years in cachectic cohorts. Pre-treatment cachexia was not a predictor of disease-free survival and further data are required to establish its influence on postoperative mortality. The proportion of patients with stage III/IV disease was a significant moderator of between-study heterogeneity. Cachexia may have a greater influence on overall survival in studies where more patients have a locally advanced malignancy.

CONCLUSION

Pre-treatment cachexia adversely influences overall survival following resection of an oesophagogastric malignancy.

Value of serological markers for early diagnosis and prognosis prediction of pancreatic cancer

Pancreatic cancer (PC) is a kind of malignant tumor with a poor prognosis. Its incidence rate is almost equal to the mortality rate, which shows an increasing trend, especially in recent years. At present, the radical cure of pancreatic cancer is mainly achieved by surgery, but the complex pathophysiology, the lack of early diagnosis and prognostic markers, and low surgical survival rate are the main obstacles to surgical treatment of pancreatic cancer. Serological markers are sensitive biological markers, and they have been used in recent years for the diagnosis and prediction of the prognosis of patients with postoperative pancreatic cancer. Therefore, serum markers are of vital importance in pancreatic cancer. This article summarizes various serological markers for early diagnosis and prognosis prediction of pancreatic cancer to provide a theoretical reference for clinical workers.

Understanding Cancer Cachexia and Its Implications in Upper Gastrointestinal Cancers

OPINION STATEMENT

Considerable advances in the investigation and management of oesophagogastric cancer have occurred over the last few decades. While the historically dismal prognosis associated with these diseases has improved, outcomes remain very poor. Cancer cachexia is an often neglected, yet critical, factor for this patient group. There is a persuasive argument that a lack of assessment and treatment of cachexia has limited progress in oesophagogastric cancer care. In the curative setting, the stage of the host (based on factors such as body composition, function, and inflammatory status), alongside tumour stage, has the potential to influence treatment efficacy. Phenotypical features of cachexia may decrease the survival benefit of (peri-operative) chemoradiotherapy, immunotherapy, or surgical resection in patients with potentially curative malignancy. Most patients with oesophagogastric cancer unfortunately present with disease which is not amenable, or is unlikely to respond, to these treatments. In the palliative setting, host factors can similarly impair results from systemic anti-cancer therapies, cause adverse symptoms, and reduce quality of life. To optimise treatment pathways and enhance patient outcomes, we must utilise this information during clinical decision-making. As our understanding of the genesis of cancer cachexia improves and more therapeutic options, ranging from basic (e.g. exercise and nutrition) to targeted (e.g. anti-IL1 α and anti-GDF-15), become available, there can be grounds for optimism. Cachexia can change from a hitherto neglected condition to an integral part of the oesophagogastric cancer treatment pathway.

Single nuclei RNA sequencing of the rat AP and NTS following GDF15 treatment

Objective

Growth differentiation factor 15 (GDF15) is known to play a role in feeding, nausea, and body weight, with action through the GFRAL-RET receptor complex in the area postrema (AP) and nucleus tractus solitarius (NTS). To further elucidate the underlying cell type-specific molecular mechanisms downstream of GDF15 signaling, we used a single nuclei RNA sequencing (snRNAseq) approach to profile AP and NTS cellular subtype-specific transcriptomes after systemic GDF15 treatment.

Methods

AP and NTS micropunches were used for snRNAseq from Sprague Dawley rats 6 h following GDF15 or saline injection, and Seurat was used to identify cellular subtypes and cell type-specific alterations in gene expression that were due to the direct and secondary effects of systemic GDF15 treatment.

Results

Using the transcriptome profile of ∼35,000 individual AP/NTS nuclei, we identified 19 transcriptomically distinct cellular subtypes, including a single population Gfral and Ret positive excitatory neurons, representing the primary site of action for GDF15. A total of ∼600 cell type-specific differential expression events were identified in neurons and glia, including the identification of transcriptome alterations specific to the direct effects of GDF15 in the Gfral-Ret positive excitatory neurons and shared transcriptome alterations across neuronal and glial cell types. Downstream analyses identified shared and cell type-specific alterations in signaling pathways and upstream regulatory mechanisms of the observed transcriptome alterations.

Conclusions

These data provide a considerable advance in our understanding of AP and NTS cell type-specific molecular mechanisms associated with GDF15 signaling. The identified cellular subtype-specific regulatory mechanism and signaling pathways likely represent important targets for future pharmacotherapies.

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GDF15 directly alters transcription in Gfral- and Ret-positive excitatory neurons.

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GDF15 indirectly alters transcription in other neuronal and glial populations.

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Cell type-specific expression changes identify regulatory and signaling mechanisms.

Biomarkers in the diagnosis of pancreatic cancer: Are we closer to finding the golden ticket?

Pancreatic cancer (PC) is a leading cause of cancer related mortality on a global scale. The disease itself is associated with a dismal prognosis, partly due to its silent nature resulting in patients presenting with advanced disease at the time of diagnosis. To combat this, there has been an explosion in the last decade of potential candidate biomarkers in the research setting in the hope that a diagnostic biomarker may provide a glimmer of hope in what is otherwise quite a substantial clinical dilemma. Currently, serum carbohydrate antigen 19-9 is utilized in the diagnostic work-up of patients diagnosed with PC however this biomarker lacks the sensitivity and specificity associated with a gold-standard marker. In the search for a biomarker that is both sensitive and specific for the diagnosis of PC, there has been a paradigm shift towards a focus on liquid biopsy and the use of diagnostic panels which has subsequently proved to have efficacy in the diagnosis of PC. Currently, promising developments in the field of early detection on PC using diagnostic biomarkers include the detection of microRNA (miRNA) in serum and circulating tumour cells. Both these modalities, although in their infancy and yet to be widely accepted into routine clinical practice, possess merit in the early detection of PC. We reviewed over 300 biomarkers with the aim to provide an in-depth summary of the current state-of-play regarding diagnostic biomarkers in PC (serum, urinary, salivary, faecal, pancreatic juice and biliary fluid).

Association between Growth Differentiation Factor-15 (GDF-15) Serum Levels, Anorexia and Low Muscle Mass among Cancer Patients

Simple Summary

In our study, the novel inflammatory cytokine Growth Differentiation Factor-15 (GDF-15) has been found elevated in patients with gastrointestinal and lung cancer and associated with anorexia. Patients with gastrointestinal cancer were found more anorexic (based on the FAACT score) and showed higher GDF-15 serum levels than patients with lung cancer. We also evaluated the muscularity status of the patients by CT scan. No difference was found in GDF-15 levels between cancer patients with low muscle mass vs. those with moderate/high muscularity and between patients with body weight loss vs. those with stable weight. Based on our observations, we confirm the role of GDF-15 in the pathogenesis of anorexia in cancer, although the mechanisms of action of this cytokine in cancer should be further unveiled also regarding its potential involvement in changes in muscularity.

Abstract

The pathophysiology of cancer anorexia is complex and serum biomarkers, including growth and differentiation factor(s) (GDF), may be modulated. We explored the association(s) between GDF-15 serum levels and anorexia and, secondarily, with low muscle mass and body weight loss in cancer patients. We considered gastrointestinal and lung cancer patients (CP) and healthy BMI-matched controls. The FAACT-questionnaire was administered to diagnose anorexia and we calculated the L3-SMI by CT scan to assess low muscularity, setting their cutoff values at the lowest tertile. GDF-15 serum levels were assessed by ELISA. We enrolled 59 CP and 30 controls; among CP, 25 were affected by gastrointestinal and 34 by lung cancer. Anorexia was present in 36% of CP. Gastrointestinal CP resulted more anorexic compared to lung CP (p = 0.0067). Low muscle mass was present in 33.9% of CP and L3-SMI was lower in gastrointestinal compared to lung CP (p = 0.049). The GDF-15 levels were higher in CP vs. controls (p = 0.00016), as well as in anorexic vs. non-anorexic CP (p = 0.005) and vs. controls (p < 0.0001). Gastrointestinal CP showed higher GDF-15 levels vs. lung CP (p = 0.0004). No difference was found in GDF-15 between CP with low muscle mass and those with moderate/high muscularity and between patients with body weight loss and those with stable weight. Our data support the involvement of GDF-15 in the pathogenesis of cancer anorexia. The mechanisms of action of GDF-15 in cancer should be further clarified also regarding the changes in muscularity.

GDF15: A Hormone Conveying Somatic Distress to the Brain

GDF15 has recently gained scientific and translational prominence with the discovery that its receptor is a GFRAL-RET heterodimer of which GFRAL is expressed solely in the hindbrain. Activation of this receptor results in reduced food intake and loss of body weight and is perceived and recalled by animals as aversive. This information encourages a revised interpretation of the large body of previous research on the protein. GDF15 can be secreted by a wide variety of cell types in response to a broad range of stressors. We propose that central sensing of GDF15 via GFRAL-RET activation results in behaviors that facilitate the reduction of exposure to a noxious stimulus. The human trophoblast appears to have hijacked this signal, producing large amounts of GDF15 from early pregnancy. We speculate that this encourages avoidance of potential teratogens in pregnancy. Circulating GDF15 levels are elevated in a range of human disease states, including various forms of cachexia, and GDF15-GFRAL antagonism is emerging as a therapeutic strategy for anorexia/cachexia syndromes. Metformin elevates circulating GDF15 chronically in humans and the weight loss caused by this drug appears to be dependent on the rise in GDF15. This supports the concept that chronic activation of the GDF15-GFRAL axis has efficacy as an antiobesity agent. In this review, we examine the science of GDF15 since its identification in 1997 with our interpretation of this body of work now being assisted by a clear understanding of its highly selective central site of action.

Macrophage inhibitory cytokine-1/growth differentiation factor-15 in premalignant and neoplastic tumours in a high-risk pancreatic cancer cohort

BACKGROUND

Pancreatic cancer (PC) is a leading cause of cancer related mortality worldwide, with poor survival due to late diagnosis. Currently, biomarkers have limited use in early diagnosis of PC. Macrophage inhibitory cytokine-1 or growth differentiation factor-15 (MIC-1/GDF15) has been implicated as a potential serum biomarker in PC and other malignancies.

AIM

To determine the role of MIC-1/GDF15 in detecting pre-malignant pancreatic lesions and neoplastic tumours in an asymptomatic high-risk cohort part of Australian Pancreatic Cancer Screening Program.

METHODS

A feasibility prospective single centre cohort study was performed. Participants recruited for yearly surveillance with endoscopic ultrasound (EUS) had serial fasting blood samples collected before EUS for MIC-1/GDF15, C-reactive protein and carbohydrate antigen 19-9. Patients were stratified into five groups based on EUS findings: Normal; pancreatic cysts, branch-duct intraductal papillary mucinous neoplasm; diffuse non-specific abnormalities; and neoplastic tumours. MIC-1/GDF15 serum levels were quantified using ELISA. Participants in whom EUS demonstrated abnormalities but not malignancy were closely followed up with magnetic resonance imaging (MRI) or computed tomography.

RESULTS

One hundred twenty participants were prospectively recruited from 2011-2018. Forty-seven participants (39.2%) had an abnormal EUS and five participants (4.2%) were diagnosed with neoplastic tumours, three by EUS (two pancreatic and one liver) and two by MRI/computed tomography (breast cancer, bladder cancer), which were performed for follow up of abnormal EUS. Baseline serum MIC-1/GDF15 was a significant predictor of neoplastic tumours on receiver operator characteristic curve analysis [area under curve (AUC) = 0.814, P = 0.023]. Baseline serum MIC-1/GDF15 had moderate predictive capacity for branch-duct intraductal papillary mucinous neoplasm (AUC = 0.644) and neoplastic tumours noted on EUS (AUC = 0.793), however this was not significant (P = 0.188 and 0.081 respectively). Serial serum MIC-1/GDF15 did not demonstrate a significant percentage change between a normal and abnormal EUS (P = 0.213). Median baseline MIC-1/GDF15 was greater in those with neoplastic tumours (Median = 1039.6, interquartile range = 727.0-1977.7) compared to those diagnosed with a benign lesion (Median = 570.1, interquartile range = 460.7-865.2) on EUS and MRI (P = 0.012).

CONCLUSION

In this pilot study MIC-1/GDF15 has predictive capacity for neoplastic tumours in asymptomatic individuals with a genetic predisposition for PC. Further imagining may be warranted in patients with abnormal EUS and raised serum MIC-1/GDF15. Larger multicentric prospective studies are required to further define the role of MIC-1/GDF15 as a serological biomarker in pre-malignant pancreatic lesions and neoplastic tumours.

Simple acute phase protein score to predict long-term survival in patients with acute myeloid leukemia

High levels of acute phase reactants can be associated with adverse outcome in patients with various solid tumor types. For patients with acute myeloid leukemia (AML), this correlation is unknown. We retrospectively investigated the prognostic value of pretreatment acute phase protein levels in 282 consecutive newly diagnosed AML patients undergoing at least one cycle of intensive induction chemotherapy. We applied a new score integrating pre-treatment C-reactive protein (CRP), fibrinogen, and albumin levels termed the CFA ratio, and we stratified patients into two groups: Patients with a CFA ratio below 3.06 had decisively better progression-free (26.2 vs 7.7 months; P < .001), disease-free (56.4 vs 8.7 months; P < .001), and overall survival (61.2 vs 13.8 months; P < .001). Results remained significant when adjusting for confounders including European Leukemia Network risk group. Early mortality also tended to be lower in the low CFA ratio group. Finally, patients with lower modified Glasgow prognostic score (mGPS) similarly had better outcome. In conclusion, our data suggest that an elevated CFA ratio as well as a high mGPS are associated with adverse outcome in patients with newly diagnosed AML undergoing intensive induction. These parameters should undergo prospective evaluation for their contribution to risk profiling in AML patients.

Growth differentiation factor 15 and its role in carcinogenesis: an update

Growth differentiation factor-15 (GDF-15) is a novel cytokine secreted by a variety of cells like macrophages, adipocytes, normally expressed in high amounts by placenta. It is also highly expressed in multiple carcinomas like Colon, Breast, Pancreas, Liver, and Ovarian. Several reports on serum GDF-15 as a potential biomarker for diagnosis and prognosis of cancer are hampered by the lack of robust data, with large sample size and critical patient recruitment. However, experimental accounts on cancer tumors, cell lines, and animal models suggest GDF-15's role in cancer progression via endothelial mesenchymal transition, angiogenesis, metastasis, drug resistance and even stemness of various cancers. GDF-15 could be the point of amalgamation for the various hallmarks of cancer and can prove a useful therapeutic target in cancer. The current review was conceptualized with a thought of critically appraising the existing information of GDF-15 in carcinogenesis.

Appraising growth differentiation factor 15 as a promising biomarker in digestive system tumors: a meta-analysis

Background

Previous studies have highlighted cytokine growth differentiation factor 15 (GDF-15) as a potential biomarker for digestive system tumors (DST). This study sought to assess the feasibility of using GDF-15 as a diagnostic and prognostic biomarker in DST.

Methods

Eligible studies from multiple online databases were reviewed. Meta-analyses of diagnostic parameters were carried out using standard statistical methods. Study-specific hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated to estimate the strength of the relationship between GDF-15 levels and clinical prognosis.

Results

We identified 17 eligible studies comprising 3966 patients with DST. The sensitivity, specificity, and area under the curve (AUC) for the discriminative performance of GDF-15 as a diagnostic biomarker were 0.74 (95% CI: 0.68–0.80), 0.83 (95% CI: 0.75–0.89), and 0.84, respectively. Moreover, increased GDF-15 expression levels were markedly associated with unfavorable overall survival (OS) in patients with DST (HR = 2.34, 95% CI: 2.03–2.70, P < 0.001; I² = 0.0%) and colorectal cancer (CRC) (HR = 2.27, 95% CI: 1.96–2.63, P < 0.001; I² = 0.0%). Stratification by cancer type, test matrix, ethnicity, and cut-off setting also illustrated the robustness of the diagnostic value of GDF-15 in DST.

Conclusion

Collectively, our data suggest that GDF-15 expression level may have value as a diagnostic and prognostic biomarker, independent of other, traditional biomarkers.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5385-y) contains supplementary material, which is available to authorized users.

Utility of GDF-15 as a diagnostic biomarker in gastric cancer: an investigation combining GEO, TCGA and meta-analysis

It was recently suggested that growth differentiation factor-15 (GDF-15) is associated with gastric cancer (GC) carcinogenesis. However, the diagnostic potential of GDF-15 for GC remains unclear. To address this issue, we obtained RNA sequencing and microarray data from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases, and searched PubMed, Google Scholar and Web of Science for relevant literature. We then used STATA to perform a meta-analysis. In total, reports of 253 GC patients and 112 healthy controls who contributed peripheral blood samples were taken from the four literature sources, while information on 754 GC tumor and 263 gastric normal tissues was drawn from TCGA and seven GEO datasets. The expression level of GDF-15 mRNA was significantly higher in tumor tissues than in normal tissues, with a standard mean difference (SMD) of 0.79% and a 95% confidence interval (95% CI) of 0.63-0.95. Consistently, the GDF-15 protein in blood was significantly increased in GC patients as compared to controls (SMD  = 3.74, 95% CI = 1.81-5.68). In addition, based on information from TCGA and GEO datasets, the expression level of GDF-15 mRNA may be of use for the diagnosis of GC, with a combined sensitivity, specificity and odds ratio of 0.69 (95% CI = 0.58-0.79), 0.90 (95% CI = 0.84-0.93) and 6.32 (95% CI = 4.22-9.49), respectively. The summary receiver operating characteristic curve demonstrated that the area under the curve was 0.90 (95% CI = 0.87-0.93). The results suggest higher levels of GDF-15 may be associated with GC tumorigenesis and may have the potential to be a diagnostic biomarker of GC.

Expression of macrophage inhibitory cytokine-1 in early gastric cancer cases treated using endoscopic mucosal resection and the correlation with prognosis

The expression of macrophage inhibitory cytokine-1 (MIC-1) of early gastric cancer treated using endoscopic mucosal resection (EMR) and its correlation with prognosis were investigated. One hundred and forty-seven patients with early gastric cancer (less than 20 mm in diameter) were recruited and assigned into an observation group (75 cases) or a control group (72 cases), according to treatment. The control group was treated with a radical resection by the conventional laparotomy approach and the observation group was treated by EMR. Differences in operative outcomes and prognosis were compared between the two groups. Complete lesion resection rates of the two groups were 100%. The amount of bleeding, operation time and postoperative complication rates in the observation group were each significantly lower than those in the control group (P<0.05). The serum MIC-1 levels in the two groups were reduced, with the observation group being significantly lower than that of the control group (P<0.05). The progression-free survival was significantly prolonged and the recurrence rate was significantly lower in the observation group compared to the control group, with the difference being statistically significant (P<0.05). In conclusion, EMR treatment of early gastric cancer was observed to be safe and effective in this study and can reduce the expression level of serum MIC-1 after the operation. EMR can also increase the survival period and reduce the recurrence rate, and MIC-1 can be used as an important index to predict the prognosis of the disease.

Anorexia-cachexia syndrome in hepatoma tumour-bearing rats requires the area postrema but not vagal afferents and is paralleled by increased MIC-1/GDF15

BACKGROUND

The cancer-anorexia-cachexia syndrome (CACS) negatively affects survival and therapy success in cancer patients. Inflammatory mediators and tumour-derived factors are thought to play an important role in the aetiology of CACS. However, the central and peripheral mechanisms contributing to CACS are insufficiently understood. The area postrema (AP) and the nucleus tractus solitarii are two important brainstem centres for the control of eating during acute sickness conditions. Recently, the tumour-derived macrophage inhibitory cytokine-1 (MIC-1) emerged as a possible mediator of cancer anorexia because lesions of these brainstem areas attenuated the anorectic effect of exogenous MIC-1 in mice.

METHODS

Using a rat hepatoma tumour model, we examined the roles of the AP and of vagal afferents in the mediation of CACS. Specifically, we investigated whether a lesion of the AP (APX) or subdiaphragmatic vagal deafferentation (SDA) attenuate anorexia, body weight, muscle, and fat loss. Moreover, we analysed MIC-1 levels in this tumour model and their correlation with tumour size and the severity of the anorectic response.

RESULTS

In tumour-bearing sham-operated animals mean daily food intake significantly decreased. The anorectic response was paralleled by a significant loss of body weight and muscle mass. APX rats were protected against anorexia, body weight loss, and muscle atrophy after tumour induction. In contrast, subdiaphragmatic vagal deafferentation did not attenuate cancer-induced anorexia or body weight loss. Tumour-bearing rats had substantially increased MIC-1 levels, which positively correlated with tumour size and cancer progression and negatively correlated with food intake.

CONCLUSIONS

These findings demonstrate the importance of the AP in the mediation of cancer-dependent anorexia and body weight loss and support a pathological role of MIC-1 as a tumour-derived factor mediating CACS, possibly via an AP-dependent action.

MAP3K11/GDF15 axis is a critical driver of cancer cachexia

BACKGROUND

Cancer associated cachexia affects the majority of cancer patients during the course of the disease and thought to be directly responsible for about a quarter of all cancer deaths. Current evidence suggests that a pro-inflammatory state may be associated with this syndrome although the molecular mechanisms responsible for the development of cachexia are poorly understood. The purpose of this work was the identification of key drivers of cancer cachexia that could provide a potential point of intervention for the treatment and/or prevention of this syndrome.

METHODS

Genetically engineered and xenograft tumour models were used to dissect the molecular mechanisms driving cancer cachexia. Cytokine profiling from the plasma of cachectic and non-cachectic cancer patients and mouse models was utilized to correlate circulating cytokine levels with the cachexia phenotype.

RESULTS

Utilizing engineered tumour models we identified MAP3K11/GDF15 pathway activation as a potent inducer of cancer cachexia. Increased expression and high circulating levels of GDF15 acted as a key mediator of this process. In animal models, tumour-produced GDF15 was sufficient to trigger the cachexia phenotype. Elevated GDF15 circulating levels correlated with the onset and progression of cachexia in animal models and in patients with cancer. Inhibition of GDF15 biological activity with a specific antibody reversed body weight loss and restored muscle and fat tissue mass in several cachectic animal models regardless of their complex secreted cytokine profile.

CONCLUSIONS

The combination of correlative observations, gain of function, and loss of function experiments validated GDF15 as a key driver of cancer cachexia and as a potential therapeutic target for the treatment and/or prevention of this syndrome.

Combined Secretomics and Transcriptomics Revealed Cancer-Derived GDF15 is Involved in Diffuse-Type Gastric Cancer Progression and Fibroblast Activation

Gastric cancer is classified into two subtypes, diffuse and intestinal. The diffuse-type gastric cancer (DGC) has poorer prognosis, and the molecular pathology is not yet fully understood. The purpose of this study was to identify functional secreted molecules involved in DGC progression. We integrated the secretomics of six gastric cancer cell lines and gene expression analysis of gastric cancer tissues with publicly available microarray data. Hierarchical clustering revealed characteristic gene expression differences between diffuse- and intestinal-types. GDF15 was selected as a functional secreted molecule owing to high expression only in fetal tissues. Protein expression of GDF15 was higher in DGC cell lines and tissues. Serum levels of GDF15 were significant higher in DGC patients as compared with healthy individuals and chronic gastritis patients, and positively correlated with wall invasion and lymph node metastasis. In addition, the stimulation of GDF15 on NIH3T3 fibroblast enhanced proliferation and up-regulated expression of extracellular matrix genes, which were similar to TGF-β stimulation. These results indicate that GDF15 contributes to fibroblast activation. In conclusion, this study revealed that GDF15 may be a novel functional secreted molecule for DGC progression, possibly having important roles for cancer progression via the affecting fibroblast function, as well as TGF-β.

Plasma growth differentiation factor 15 is associated with weight loss and mortality in cancer patients

BACKGROUND

Cancer-related weight loss is associated with increased inflammation and decreased survival. The novel inflammatory mediator growth differentiation factor (GDF)15 is associated with poor prognosis in cancer but its role in cancer-related weight loss (C-WL) remains unclear. Our objective was to measure GDF15 in plasma samples of cancer subjects and controls and establish its association with other inflammatory markers and clinical outcomes.

METHODS

We measured body weight, appetite, plasma GDF15, and other inflammatory markers in men with cancer-related weight loss (C-WL, n = 58), weight stable patients with cancer (C-WS, n = 72), and non-cancer controls (Co, n = 59) matched by age and pre-illness body mass index. In a subset of patients we also measured handgrip strength, appendicular lean body mass (aLBM), Eastern Cooperative Oncology Group (ECOG), and Karnofsky performance scores.

RESULTS

GDF15, interleukin (IL)-6 and IL-8 were increased in C-WL versus other groups. IL-1 receptor antagonist, IL-4, interferon-gamma, tumour necrosis factor alpha, and vascular endothelial growth factor A were increased in C-WL versus C-WS, and Activin A was significantly downregulated in Co versus other groups. C-WL patients had lower handgrip strength, aLBM, and fat mass, and Eastern Cooperative Oncology Group and Karnofsky performance scores were lower in both cancer groups. GDF15, IL-6, and IL-8 significantly correlated with weight loss; GDF15 negatively correlated with aLBM, handgrip strength, and fat mass. IL-8 and Activin A negatively correlated with aLBM and fat mass. GDF15 and IL-8 predicted survival adjusting for stage and weight change (Cox regression P < 0.001 for both).

CONCLUSION

GDF15 and other inflammatory markers are associated with weight loss, decreased aLBM and strength, and poor survival in patients with cancer. GDF15 may serve as a prognostic indicator in cancer patients and is being evaluated as a potential therapeutic target for cancer-related weight loss.

Anorexia-cachexia and obesity treatment may be two sides of the same coin: role of the TGF-b superfamily cytokine MIC-1/GDF15

Anorexia-cachexia associated with cancer and other diseases is a common and often fatal condition representing a large area of unmet medical need. It occurs most commonly in advanced cancer and is probably a consequence of molecules released by tumour cells, or tumour-associated interstitial or immune cells. These may then act directly on muscle to cause atrophy and/or may cause anorexia, which then leads to loss of both fat and lean mass. Although the aetiological triggers for this syndrome are not well characterized, recent data suggest that MIC-1/GDF15, a transforming growth factor-beta superfamily cytokine produced in large amounts by cancer cells and as a part of other disease processes, may be an important trigger. This cytokine acts on feeding centres in the hypothalamus and brainstem to cause anorexia leading to loss of lean and fat mass and eventually cachexia. In animal studies, the circulating concentrations of MIC-1/GDF15 required to cause this syndrome are similar to those seen in patients with advanced cancer, and at least some epidemiological studies support an association between MIC-1/GDF15 serum levels and measures of nutrition. This article will discuss its mechanisms of central appetite regulation, and the available data linking this action to anorexia-cachexia syndromes that suggest it is a potential target for therapy of cancer anorexia-cachexia and conversely may also be useful for the treatment of severe obesity.

Cachexia in patients with oesophageal cancer

Oesophageal cancer is a debilitating disease with a poor prognosis, and weight loss owing to malnutrition prevails in the majority of patients. Cachexia, a multifactorial syndrome characterized by the loss of fat and skeletal muscle mass and systemic inflammation arising from complex host-tumour interactions is a major contributor to malnutrition, which is a determinant of tolerance to treatment and survival. In patients with oesophageal cancer, cachexia is further compounded by eating difficulties owing to the stage and location of the tumour, and the effects of neoadjuvant therapy. Treatment with curative intent involves exceptionally extensive and invasive surgery, and the subsequent anatomical changes often lead to eating difficulties and severe postoperative malnutrition. Thus, screening for cachexia by means of percentage weight loss and BMI during the cancer trajectory and survivorship periods is imperative. Additionally, markers of inflammation (such as C-reactive protein), dysphagia and appetite loss should be assessed at diagnosis. Routine assessments of body composition are also necessary in patients with oesophageal cancer to enable assessment of skeletal muscle loss, which might be masked by sarcopenic obesity in these patients. A need exists for clinical trials examining the effectiveness of therapeutic and physical-activity-based interventions in mitigating muscle loss and counteracting cachexia in these patients.

The Expression of GDF-15 in the Human Vitreous in the Presence of Retinal Pathologies with an Inflammatory Component

PURPOSE

The presence of growth differentiation factor-15 (GDF-15), a protein implicated in the regulation of the inflammatory response, was investigated in the vitreous of patients with vitreoretinal disorders.

METHODS

Vitreous and plasma samples were collected from patients with idiopathic epiretinal membrane (IERM), macular hole (MH), rhegmatogenous retinal detachment (RRD), nucleus drop (ND), or proliferative diabetic retinopathy (PDR). GDF-15 concentrations were measured using ELISA.

RESULTS

The vitreous levels of GDF-15 were higher in ND (5) and PDR (14) patients (1494 ± 243 and 904 ± 138 pg/mL, respectively) than RRD (3), MH (3), and IERM (8) patients (302 ± 160, 288 ± 24, and 254 ± 91 pg/mL, respectively). The vitreous levels of GDF-15 were significantly higher in patients with inflammatory vitreoretinal disorders (p < 0.0001).

CONCLUSIONS

This is the first report showing that GDF-15 appears to be expressed in the vitreous, and that its expression is significantly higher in the presence of a vitreoretinal disorder in which there is an inflammatory component.

GDF15 derived from both tumor-associated macrophages and esophageal squamous cell carcinomas contributes to tumor progression via Akt and Erk pathways

Tumor-associated macrophages (TAMs) are known to be involved in the progression, angiogenesis, and motility of various cancers. We previously reported the association between an increased number of infiltrating TAMs with tumor progression and poor prognosis in esophageal squamous cell carcinomas (ESCCs). To study the roles of TAMs in ESCC, we first exposed peripheral blood monocyte (PBMo)-derived macrophages from healthy volunteers to conditioned media of TE series human ESCC cell line (TECM) and confirmed the induction of the expression of the M2 macrophage marker CD204 and the protumorigenic factors interleukin (IL)-10, VEGFA, and MMPs. Next, we compared gene expression profiles between PBMo-derived macrophages stimulated with or without TECM by cDNA microarray and focused on growth differentiation factor 15 (GDF15) among the highly expressed genes including IL-6, IL-8, and CXCL1. Our immunohistochemical study of 70 surgically resected ESCCs revealed that GDF15 was present not only in cancer cells but also in macrophages. The high expression of GDF15 in the ESCCs was significantly correlated with several more malignant phenotypes including vessel invasion, lymph node metastasis, and clinical stages. Patients with high GDF15 expression showed significantly poorer disease-free survival (P=0.011) and overall survival (P=0.041). We also found that recombinant human GDF15 promotes cell proliferation and the phosphorylation of both Akt and Erk1/2 in ESCC cell lines in vitro. These results indicate that GDF15 is secreted by both TAMs and cancer cells in the tumor microenvironment and is associated with aberrant growth and a poor prognosis in human ESCC.

MIC-1/GDF15 in Barrett's oesophagus and oesophageal adenocarcinoma

Background:

Biomarkers are needed to improve current diagnosis and surveillance strategies for patients with Barrett's oesophagus (BO) and oesophageal adenocarcinoma (OAC). Macrophage inhibitory cytokine 1/growth differentiation factor 15 (MIC-1/GDF15) tissue and plasma levels have been shown to predict disease progression in other cancer types and was therefore evaluated in BO/OAC.

Methods:

One hundred thirty-eight patients were studied: 45 normal oesophagus (NE), 37 BO, 16 BO with low-grade dysplasia (LGD) and 40 OAC.

Results:

Median tissue expression of MIC-1/GDF15 mRNA was ⩾25-fold higher in BO and LGD compared to NE (P<0.001); two-fold higher in OAC vs BO (P=0.039); and 47-fold higher in OAC vs NE (P<0.001). Relative MIC-1/GDF15 tissue expression >720 discriminated between the presence of either OAC or LGD vs NE with 94% sensitivity and 71% specificity (ROC AUC 0.86, 95% CI 0.73–0.96; P<0.001). Macrophage inhibitory cytokine 1/growth differentiation factor 15 plasma values were also elevated in patients with OAC vs NE (P<0.001) or BO (P=0.015).

High MIC-1/GDF15 plasma levels (⩾1140 pg ml⁻¹) were an independent predictor of poor survival for patients with OAC (HR 3.87, 95% CI 1.01–14.75; P=0.047).

Conclusions:

Plasma and tissue levels of MIC-1/GDF15 are significantly elevated in patients with BO, LGD and OAC. Plasma MIC-1/GDF15 may have value in diagnosis and monitoring of Barrett's disease.

Circulating levels of GDF15, MMP7 and miR-200c as a poor prognostic signature in gastric cancer

AIM

To analyze GDF15 and MMP7 serum levels as diagnostic biomarkers in gastric cancer (GC) patients. The prognostic value of GDF15 and MMP7 serum levels in combination with miR-200c blood expression was also analyzed.

PATIENTS & METHODS

Fifty-two GC and 23 control samples were included.

RESULTS

GDF15 and MMP7 proved to be powerful tools for GC diagnosis. Increased levels of GDF15 and MMP7 were associated with shorter progression-free survival and overall survival in univariate analysis. In multivariate analysis, the combination of high levels of GDF15, MMP7 and miR-200c was an independent predictor for death (p = 0.033).

CONCLUSION

GDF15 and MMP7 serum levels have diagnostic value for GC. The combination marker formed by GDF15, MMP7 and miR-200c is indicative of adverse evolution in GC patients.

Macrophage inhibitory cytokine 1 (MIC-1/GDF15) as a novel diagnostic serum biomarker in pancreatic ductal adenocarcinoma

Background

Macrophage inhibitory cytokine 1 (MIC-1/GDF15) has been identified as a potential novel biomarker for detection of pancreatic cancer (PCa). However, the diagnostic value of serum MIC-1 for pancreatic ductal adenocarcinoma (PDAC), particularly for those at the early stage, and the value for treatment response monitoring have not yet been investigated.

Methods

MIC-1 expression in tumor tissue was analyzed by RT-PCR from 64 patients with PDAC. Serum MIC-1 levels were detected by ELISA in 1472 participants including PDAC, benign pancreas tumor, chronic pancreatitis and normal controls. The diagnostic performance of MIC-1 was assessed and compared with CA19.9, CEA and CA242, and the value of it as a predictive indicator for therapeutic response and tumor recurrence was also evaluated.

Results

MIC-1 levels were significantly elevated in PDAC tissues as well as serum samples. The sensitivity of serum MIC-1 for PDAC diagnosis was much higher than that of CA19.9 (65.8% vs. 53.3%) with similar specificities. Furthermore, serum MIC-1 detected 238 out of 377 (63.1%) CA19.9-negative PDAC. Moreover, receiver operating characteristic (ROC) curve analysis also showed that serum MIC-1 had a better performance compared with CA19.9 in distinguishing early-stage PDAC from normal serum with a higher sensitivity (62.5% vs. 25.0% respectively). Notably, serum MIC-1 level was significantly decreased in patients with PDAC after curative resection and returned to elevated levels when tumor relapse occurred.

Conclusions

Serum MIC-1 is significantly elevated in most PDAC, including those with negative CA19.9 and early stage disease, and thus may serve as a novel diagnostic marker in early diagnosis and postoperative monitoring of PDAC.

Change of body weight and macrophage inhibitory cytokine-1 during chemotherapy in advanced gastric cancer: what is their clinical significance?

Background

Weight loss in advanced gastric cancer (GC) has been widely acknowledged to be a predictor for poor survival. However, very few studies have investigated the weight loss that occurs during chemotherapy. Therefore, we focused on weight loss during chemotherapy in patients with advanced GC and investigated the concentrations of macrophage inhibitory cytokine-1 (MIC-1), which has been recognized as a probable etiological factor in anorexia and weight loss.

Methods

We analyzed 384 patients with inoperable locally advanced or metastatic GC receiving first-line chemotherapy. Patients were assigned to one of two groups on the basis of their weight change during chemotherapy: >3% weight loss and ≤3% weight loss. Serum MIC-1 and C-reactive protein (CRP) concentrations were also assessed in these patients.

Results

The >3% weight loss group had shorter overall survival (OS; 12.0 months vs. 17.5 months, P = 0.000) than the ≤3% weight loss group, and the survival rates improved if the weight loss was reversed during chemotherapy. Although the MIC-1 concentrations were not correlated with weight loss before (P = 0.156) or during chemotherapy (P = 0.164), it correlated significantly with the CRP concentration (P = 0.001). Furthermore, elevated MIC-1 concentrations before chemotherapy (P = 0.017) and increased MIC-1 concentrations during chemotherapy (P = 0.001) were both found to be predictors of poor OS.

Conclusions

Changes in the body weight during chemotherapy could influence the prognosis in patients with advanced GC, and the MIC-1 might be a potential predictive and prognostic biomarker in those patients.

GDF-15 protects from macrophage accumulation in a mousemodel of advanced atherosclerosis

Background

The cytokine growth differentiation factor-15 (GDF-15), a member of the TGF beta superfamily, has recently been discovered to play an important role in cardiovascular diseases. It is mostly expressed in macrophages of atherosclerotic lesions, but its impact on advanced atherosclerosis is still unknown. This study was performed to evaluate the effects of GDF-15 in an established mouse model of advanced atherosclerosis.

Methods

Thirty-eight LDL receptor deficient mice received a lethal body radiation. Half of the group was transplanted with bone marrow of GDF-15 deficient mice. Nineteen mice were transplanted with bone marrow from wild-type controls. After 24 weeks on an atherogenic diet, animals were euthanized and sections of the aortic sinus were prepared. Lesion size and lesion composition, as well as macrophage content,were evaluated.

Results

While demonstrating no difference in lesion size, LDL-receptor knockout mice transplanted with bone marrow from GDF-15 deficient mice showed enhanced macrophage accumulation and features of atherosclerotic plaque destabilization, such as thinning of fibrous caps. Immunostaining against intercellular adhesion molecule-1 further revealed an increased expression in mice receiving GDF-15-deficient bone marrow.

Conclusions

This is the first study that demonstrates a protective role of GDF-15 in advanced atherosclerosis and macrophage accumulation, possibly due to the reduced expression of adhesion molecules.

Potentials of plasma NGAL and MIC-1 as biomarker(s) in the diagnosis of lethal pancreatic cancer

Pancreatic cancer (PC) is lethal malignancy with very high mortality rate. Absence of sensitive and specific marker(s) is one of the major factors for poor prognosis of PC patients. In pilot studies using small set of patients, secreted acute phase proteins neutrophil gelatinase associated lipocalin (NGAL) and TGF-β family member macrophage inhibitory cytokine-1 (MIC-1) are proposed as most potential biomarkers specifically elevated in the blood of PC patients. However, their performance as diagnostic markers for PC, particularly in pre-treatment patients, remains unknown. In order to evaluate the diagnostic efficacy of NGAL and MIC-1, their levels were measured in plasma samples from patients with pre-treatment PC patients (n = 91) and compared it with those in healthy control (HC) individuals (n = 24) and patients with chronic pancreatitis (CP, n = 23). The diagnostic performance of these two proteins was further compared with that of CA19-9, a tumor marker commonly used to follow PC progression. The levels of all three biomarkers were significantly higher in PC compared to HCs. The mean (± standard deviation, SD) plasma NGAL, CA19-9 and MIC-1 levels in PC patients was 111.1 ng/mL (2.2), 219.2 U/mL (7.8) and 4.5 ng/mL (4.1), respectively. In comparing resectable PC to healthy patients, all three biomarkers were found to have comparable sensitivities (between 64%-81%) but CA19-9 and NGAL had a higher specificity (92% and 88%, respectively). For distinguishing resectable PC from CP patients, CA19-9 and MIC-1 were most specific (74% and 78% respectively). CA19-9 at an optimal cut-off of 54.1 U/ml is highly specific in differentiating resectable (stage 1/2) pancreatic cancer patients from controls in comparison to its clinical cut-off (37.1 U/ml). Notably, the addition of MIC-1 to CA19-9 significantly improved the ability to distinguish resectable PC cases from CP (p = 0.029). Overall, MIC-1 in combination with CA19-9 improved the diagnostic accuracy of differentiating PC from CP and HCs.

Anorexia/cachexia of chronic diseases: a role for the TGF-β family cytokine MIC-1/GDF15

Anorexia/cachexia is a common and currently mostly untreatable complication of advanced cancer. It is also a feature of a number of chronic diseases and can also occur as part of the normal ageing process. Over recent years, two different, but sometimes overlapping, processes have been identified to mediate anorexia/cachexia: those that act primarily on muscle reducing its mass and function, and processes that decrease nutrition leading to loss of both fat and muscle. In the case of at least some cancers, the latter process is sometimes driven by marked overexpression of macrophage inhibitory cytokine-1/growth differentiation factor 15 (MIC-1/GDF15). MIC-1/GDF15 is a transforming growth factor beta (TGF-β) family cytokine that is found in the serum of all normal individuals at an average concentration of about 0.6 ng/ml. Its increased expression in both cancers and other diseases can result in 10-100-fold or more elevation of its serum levels. In experimental animals, serum MIC-1/GDF15 levels at the lower end of this range induce anorexia by direct actions of the circulating cytokine on feeding centres in the brain. Mice with tumours overexpressing MIC-1/GDF15 display decreased food intake, loss of lean and fat mass and cachexia. That this process also mediates anorexia/cachexia in humans is suggested by the fact that there is a direct correlation between the degree of serum MIC-1/GDF15 elevation and the amount of cancer-related weight loss, the first such relationship demonstrated. Further, in experimental animals, weight loss can be reversed by neutralisation of tumour-produced MIC-1/GDF15 with a specific monoclonal antibody, suggesting the possibility of effective therapy of patients with the devastating complication of anorexia/cachexia.

The systemic inflammation-based Glasgow Prognostic Score: a decade of experience in patients with cancer

Since the initial work, a decade ago that the combination of C-reactive protein and albumin, the Glasgow Prognostic Score (GPS), had independent prognostic value in patients with cancer, there have been more than 60 studies (>30,000 patients) that have examined and validated the use of the GPS or the modified GPS (mGPS) in a variety of cancer scenarios. The present review provides a concise overview of these studies and comments on the current and future clinical utility of this simple objective systemic inflammation-based score. The GPS/mGPS had independent prognostic value in (a) unselected cohorts (4 studies, >19,400 patients) (b) operable disease (28 studies, >8,000 patients) (c) chemo/radiotherapy (11 studies, >1500 patients) (d) inoperable disease (11 studies, >2,000 patients). Association studies (15 studies, >2,000 patients) pointed to an increased GPS/mGPS being associated with increased weight and muscle loss, poor performance status, increased comorbidity, increased pro-inflammatory and angiogenic cytokines and complications on treatment. These studies have originated from 13 different countries, in particular the UK and Japan. A chronic systemic inflammatory response, as evidenced by the GPS/mGPS, is clearly implicated in the prognosis of patients with cancer in a variety of clinical scenarios. The GPS/mGPS is the most extensively validated of the systemic inflammation-based prognostic scores and therefore may be used in the routine clinical assessment of patients with cancer. It not only identifies patients at risk but also provides a well defined therapeutic target for future clinical trials. It remains to be determined whether the GPS has prognostic value in other disease states.

mRNA profiling of the cancer degradome in oesophago-gastric adenocarcinoma

Background:

Degradation of the extracellular matrix is fundamental to tumour development, invasion and metastasis. Several protease families have been implicated in the development of a broad range of tumour types, including oesophago–gastric (OG) adenocarcinoma. The aim of this study was to analyse the expression levels of all core members of the cancer degradome in OG adenocarcinoma and to investigate the relationship between expression levels and tumour/patient variables associated with poor prognosis.

Methods:

Comprehensive expression profiling of the protease families (matrix metalloproteinases (MMPs), members of the ADAM metalloproteinase-disintegrin family (ADAMs)), their inhibitors (tissue inhibitors of metalloproteinase), and molecules involved in the c-Met signalling pathway, was performed using quantitative real-time reverse transcription polymerase chain reaction in a cohort of matched malignant and benign peri-tumoural OG tissue (n=25 patients). Data were analysed with respect to clinico-pathological variables (tumour stage and grade, age, sex and pre-operative plasma C-reactive protein level).

Results:

Gene expression of MMP1, 3, 7, 9, 10, 11, 12, 16 and 24 was upregulated by factors >4-fold in OG adenocarcinoma samples compared with matched benign tissue (P<0.01). Expression of ADAM8 and ADAM15 correlated significantly with tumour stage (P=0.048 and P=0.044), and ADAM12 expression correlated with tumour grade (P=0.011).

Conclusion:

This study represents the first comprehensive quantitative analysis of the expression of proteases and their inhibitors in human OG adenocarcinoma. These findings implicate elevated ADAM8, 12 and 15 mRNA expression as potential prognostic molecular markers.

Growth/differentiation factor-15: prostate cancer suppressor or promoter?

Deregulation of expression and function of cytokines belonging to the transforming growth factor-β (TGF-β) family is often associated with various pathologies. For example, this cytokine family has been considered a promising target for cancer therapy. However, the detailed functions of several cytokines from the TGF-β family that could have a role in cancer progression and therapy remain unclear. One of these molecules is growth/differentiation factor-15 (GDF-15), a divergent member of the TGF-β family. This stress-induced cytokine has been proposed to possess immunomodulatory functions and its high expression is often associated with cancer progression, including prostate cancer (PCa). However, studies clearly demonstrating the mechanisms for signal transduction and functions in cell interaction, cancer progression and therapy are still lacking. New GDF-15 roles have recently been identified for modulating osteoclast differentiation and for therapy for PCa bone metastases. Moreover, GDF-15 is as an abundant cytokine in seminal plasma with immunosuppressive properties. We discuss studies that focus on the regulation of GDF-15 expression and its role in tissue homeostasis, repair and the immune response with an emphasis on the role in PCa development.

Molecular mechanisms of cachexia in chronic disease

Cachexia is a metabolic syndrome that manifests with excessive weight loss and disproportionate muscle wasting. It is related to many different chronic diseases, such as cancer, infections, liver disease, inflammatory bowel disease, cardiac disease, chronic obstructive pulmonary disease, chronic renal failure and rheumatoid arthritis. Cachexia is linked with poor outcome for the patients. In this article, we explore the role of the hypothalamus, liver, muscle tissue and adipose tissue in the pathogenesis of this syndrome, particularly concentrating on the role of cytokines, hormones and cell energy-controlling pathways (such as AMPK, PI3K/Akt and mTOR). We also look at possible future directions for therapeutic strategies.

The TGF-β superfamily cytokine, MIC-1/GDF15: a pleotrophic cytokine with roles in inflammation, cancer and metabolism

Macrophage inhibitory cytokine-1 (MIC-1/GDF15) is associated with cardiovascular disease, inflammation, body weight regulation and cancer. Its serum levels facilitate the diagnosis and prognosis of cancer and vascular disease. Furthermore, its serum levels are a powerful predictor of all-cause mortality, suggesting a fundamental role in biological processes associated with ageing. In cancer, the data available suggest that MIC-1/GDF15 is antitumorigenic, but this may not always be the case as disease progresses. Cancer promoting effects of MIC-1/GDF15 may be due, in part, to effects on antitumour immunity. This is suggested by the anti-inflammatory and immunosuppressive properties of MIC-1/GDF15 in animal models of atherosclerosis and rheumatoid arthritis. Furthermore, in late-stage cancer, large amounts of MIC-1/GDF15 in the circulation suppress appetite and mediate cancer anorexia/cachexia, which can be reversed by monoclonal antibodies in animals. Available data suggest MIC-1/GDF15 may be an important molecule mediating the interplay between cancer, obesity and chronic inflammation.

Clinical pathological significance of MIC-1 and uPA expression in esophageal squamous cell carcinoma

AIM: To explore the relationship of the protein expression of macrophage inhibitory cytokine-1 (MIC-1) and urokinase plasminogen activator (uPA) with the development, progression, invasion and metastasis of esophageal squamous cell carcinoma (ESCC).

METHODS: The protein expression of MIC-1 and uPA was detected by immunohistochemistry using the streptavidin-peroxidase method in 45 ESCC specimens, 22 tumor-adjacent atypical hyperplastic epithelial specimens and 45 normal esophageal epithelial specimens.

RESULTS: The expression of MIC-1 protein was closely correlated with tumor grade, infiltration, TNM grade and lymphatic metastasis in ESCC (all P < 0.05). The expression of uPA protein was closely correlated with tumor TNM grade and lymphatic metastasis in ESCC (both P < 0.05). The positive rates of MIC-1 expression in ESCC, tumor-adjacent atypical hyperplastic epithelium and normal esophageal epithelium were 64.4% (29/45), 40.9% (9/22) and 13.3% (6/45), respectively, with a significant difference among the three groups (χ² = 24.673, P < 0.01). The positive rates of UPA protein expression in ESCC, tumor-adjacent atypical hyperplastic epithelium and normal esophageal epithelium were 68.9% (31/45), 27.3% (6/22) and 24.4% (11/45), respectively, with a significant difference among the three groups (P < 0.01). There is a positive correlation between the protein expression of MIC-1 and uPA (γ_p = 0.403, P < 0.01).

CONCLUSION: MIC-1 and uPA play important roles in the carcinogenesis, infiltration and metastasis of ESCC. Combined detection of MIC-1 and uPA expression may be a promising molecular parameter for early diagnosis and prognostic evaluation of ESCC.