Administration of adiponectin receptor agonist AdipoRon relieves cancer cachexia by mitigating inflammation in tumour-bearing mice.

BACKGROUND: Cancer cachexia is a life-threatening, inflammation-driven wasting syndrome that remains untreatable. Adiponectin, the most abundant adipokine, plays an important role in several metabolic processes as well as in inflammation modulation. Our aim was to test whether administration of AdipoRon (AR), a synthetic agonist of the adiponectin receptors, prevents the development of cancer cachexia and its related muscle atrophy. METHODS: The effect of AR on cancer cachexia was investigated in two distinct murine models of colorectal cancer. First, 7-week-old CD2F1 male mice were subcutaneously injected with colon-26 carcinoma cells (C26) or vehicle (CT). Six days after injection, mice were treated for 5 days with AdipoRon (50 mg/kg/day; C26 + AR) or the corresponding vehicle (CT and C26). Additionally, a genetic model, the ApcMin/+ mouse, that develops spontaneously numerous intestinal polyps, was used. Eight-week-old male ApcMin/+ mice were treated with AdipoRon (50 mg/kg/day; Apc + AR) or the corresponding vehicle (Apc) over a period of 12 weeks, with C57BL/6J wild-type mice used as controls. In both models, several parameters were assessed in vivo: body weight, grip strength and serum parameters, as well as ex vivo: molecular changes in muscle, fat and liver. RESULTS: The protective effect of AR on cachexia development was observed in both cachectic C26 and ApcMin/+ mice. In these mice, AR administration led to a significant alleviation of body weight loss and muscle wasting, together with rescued muscle strength (P < 0.05 for all). In both models, AR had a strong anti-inflammatory effect, reflected by lower systemic interleukin-6 levels (-55% vs. C26, P < 0.001 and -80% vs. Apc mice, P < 0.05), reduced muscular inflammation as indicated by lower levels of Socs3, phospho-STAT3 and Serpina3n, an acute phase reactant (P < 0.05 for all). In addition, AR blunted circulating levels of corticosterone (-46% vs. C26 mice, P < 0.001 and -60% vs. Apc mice, P < 0.05), the predominant murine glucocorticoid known to induce muscle atrophy. Accordingly, key glucocorticoid-responsive factors implicated in atrophy programmes were-or tended to be-significantly blunted in skeletal muscle by AR. Finally, AR protected against lipid metabolism alterations observed in ApcMin/+ mice, as it mitigated the increase in circulating triglyceride levels (-38%, P < 0.05) by attenuating hepatic triglyceride synthesis and fatty acid uptake by the liver. CONCLUSIONS: Altogether, these results show that AdipoRon rescued the cachectic phenotype by alleviating body weight loss and muscle atrophy, along with restraining inflammation and hypercorticism in preclinical murine models. Therefore, AdipoRon could represent an innovative therapeutic strategy to counteract cancer cachexia.

Tumoral acidosis promotes adipose tissue depletion by fostering adipocyte lipolysis.

OBJECTIVE: Tumour progression drives profound alterations in host metabolism, such as adipose tissue depletion, an early event of cancer cachexia. As fatty acid consumption by cancer cells increases upon acidosis of the tumour microenvironment, we reasoned that fatty acids derived from distant adipose lipolysis may sustain tumour fatty acid craving, leading to the adipose tissue loss observed in cancer cachexia. METHODS: To evaluate the pro-lipolytic capacities of acid-exposed cancer cells, primary mouse adipocytes from subcutaneous and visceral adipose tissue were exposed to pH-matched conditioned medium from human and murine acid-exposed cancer cells (pH 6.5), compared to naive cancer cells (pH 7.4). To further address the role of tumoral acidosis on adipose tissue loss, a pH-low insertion peptide was injected into tumour-bearing mice, and tumoral acidosis was neutralised with a sodium bicarbonate buffer. Prolipolytic mediators were identified by transcriptomic approaches and validated on murine and human adipocytes. RESULTS: Here, we reveal that acid-exposed cancer cells promote lipolysis from subcutaneous and visceral adipocytes and that dampening acidosis in vivo inhibits adipose tissue depletion. We further found a set of well-known prolipolytic factors enhanced upon acidosis adaptation and unravelled a role for ß-glucuronidase (GUSB) as a promising new actor in adipocyte lipolysis. CONCLUSIONS: Tumoral acidosis promotes the mobilization of fatty acids derived from adipocytes via the release of soluble factors by cancer cells. Our work paves the way for therapeutic approaches aimed at tackling cachexia by targeting the tumour acidic compartment.

Identification of myokines susceptible to improve glucose homeostasis after bariatric surgery.

IMPORTANCE AND OBJECTIVE: The identification of myokines susceptible to improve glucose homeostasis following bariatric surgery could lead to new therapeutic approaches for type 2 diabetes. METHODS: Changes in the homeostasis model assessment (HOMA) test were assessed in patients before and 3 months after bariatric surgery. Changes in myokines expression and circulating levels were assessed using real-time quantitative polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA). Myokines known to regulate glucose homeostasis were identified using literature (targeted study) and putative myokines using RNA-sequencing (untargeted study). A linear regression analysis adjusted for age and sex was used to search for associations between changes in the HOMA test and changes in myokines. RESULTS: In the targeted study, brain-derived neurotrophic factor (BDNF) expression was upregulated (+30%, P = .006) while BDNF circulating levels were decreased (-12%, P = .001). Upregulated BDNF expression was associated with decreased HOMA of insulin resistance (HOMA-IR) (adjusted estimate [95% confidence interval {CI}]: -0.51 [-0.88 to -0.13], P = .010). Decreased BDNF serum levels were associated with decreased HOMA of beta-cell function (HOMA-B) (adjusted estimate [95% CI] = 0.002 [0.00002-0.0031], P = .046). In the untargeted study, upregulated putative myokines included XYLT1 (+64%, P < .001), LGR5 (+57, P< .001), and SPINK5 (+46%, P < .001). Upregulated LGR5 was associated with decreased HOMA-IR (adjusted estimate [95% CI] = -0.50 [-0.86 to -0.13], P = .009). Upregulated XYLT1 and SPINK5 were associated with increased HOMA of insulin sensitivity (HOMA-S) (respectively, adjusted estimate [95% CI] = 109.1 [28.5-189.8], P = .009 and 16.5 [0.87-32.19], P = .039). CONCLUSIONS: Improved glucose homeostasis following bariatric surgery is associated with changes in myokines expression and circulating levels. In particular, upregulation of BDNF, XYLT1, SPINK5, and LGR5 is associated with improved insulin sensitivity. These results suggest that these myokines could contribute to improved glucose homeostasis following bariatric surgery. STUDY REGISTRATION: NCT03341793 on ClinicalTrials.gov (https://clinicaltrials.gov/).

EDA2R-NIK signalling promotes muscle atrophy linked to cancer cachexia.

Skeletal muscle atrophy is a hallmark of the cachexia syndrome that is associated with poor survival and reduced quality of life in patients with cancer1. Muscle atrophy involves excessive protein catabolism and loss of muscle mass and strength2. An effective therapy against muscle wasting is currently lacking because mechanisms driving the atrophy process remain incompletely understood. Our gene expression analysis in muscle tissues indicated upregulation of ectodysplasin A2 receptor (EDA2R) in tumour-bearing mice and patients with cachectic cancer. Here we show that activation of EDA2R signalling promotes skeletal muscle atrophy. Stimulation of primary myotubes with the EDA2R ligand EDA-A2 triggered pronounced cellular atrophy by induction of the expression of muscle atrophy-related genes Atrogin1 and MuRF1. EDA-A2-driven myotube atrophy involved activation of the non-canonical NFĸB pathway and was dependent on NFκB-inducing kinase (NIK) activity. Whereas EDA-A2 overexpression promoted muscle wasting in mice, deletion of either EDA2R or muscle NIK protected tumour-bearing mice from loss of muscle mass and function. Tumour-induced oncostatin M (OSM) upregulated muscle EDA2R expression, and muscle-specific oncostatin M receptor (OSMR)-knockout mice were resistant to tumour-induced muscle wasting. Our results demonstrate that EDA2R-NIK signalling mediates cancer-associated muscle atrophy in an OSM-OSMR-dependent manner. Thus, therapeutic targeting of these pathways may be beneficial in prevention of muscle loss.

Distalization of Standard Roux-en-Y Gastric Bypass: Indications, Technique, and Long-Term Results.

INTRODUCTION: Weight loss failure or weight regain after primary Roux-en-Y gastric bypass (RYGB) is a challenge for bariatric surgeons. Failure to achieve a body mass index (BMI) <35 kg/m2 after RYGB occurs in up to 40.0%. The aim of this study was to evaluate long-term results of a novel technique for distalization of Roux-en-Y gastric bypass (DRYGB) as a revisional procedure. METHODS: Retrospective data were reviewed for 22 patients who had undergone RYGB and failed to achieve an excess weight loss (EWL) >50% or BMI <35 kg/m2 and underwent limb distalization between 2013 and 2022. For this DRYGB procedure, the length of the common channel was 100 cm, and the lengths of the biliopancreatic limb and the alimentary limb were 1/3 and 2/3 of the remaining bowel, respectively. RESULTS: The mean BMI values before and after DRYGB were 43.7 kg/m2 and 33.5 kg/m2, respectively. Five years after DRYGB, mean % EWL was 74.3% and mean % total weight loss (TWL) was 28.8%. Mean % EWL and mean % TWL of the two procedures (RYGB and DRYGB) after 5 years were 80.9% and 44.7%, respectively. Three patients experienced protein calorie malnutrition. One was reproximalized and the others were treated with parenteral nutrition with no recurrence. There was a significant decrease in the incidence of diabetes type 2 and dyslipidemia after DRYGB. CONCLUSION: The DRYGB procedure results in substantial and sustained long-term weight loss. Due to the risk of malnutrition, patients must be strictly followed for life after the procedure.

Activin A Causes Muscle Atrophy through MEF2C-Dependent Impaired Myogenesis.

Activin A (ActA) is considered to play a major role in cancer-induced cachexia (CC). Indeed, circulating ActA levels are elevated and predict survival in patients with CC. However, the mechanisms by which ActA mediates CC development and in particular skeletal muscle (SM) atrophy in humans are not yet fully understood. In this work, we aimed to investigate the effects of ActA on human SM and in mouse models of CC. We used a model of human muscle cells in culture to explore how ActA acts towards human SM. In this model, recombinant ActA induced myotube atrophy associated with the decline of MyHC-ß/slow, the main myosin isoform in human muscle cells studied. Moreover, ActA inhibited the expression and activity of MEF2C, the transcription factor regulating MYH7, the gene which codes for MyHC-ß/slow. This decrease in MEF2C was involved in the decline of MyHC-ß/slow expression, since inhibition of MEF2C by a siRNA leads to the decrease in MyHC-ß/slow expression. The relevance of this ActA/MEF2C pathway in vivo was supported by the parallel decline of MEF2C expression and SM mass, which are both blunted by ActA inhibition, in animal models of CC. In this work, we showed that ActA is a potent negative regulator of SM mass by inhibiting MyHC-ß/slow synthesis through downregulation of MEF2C. This observation highlights a novel interaction between ActA signaling and MEF2C transcriptional activity which contributes to SM atrophy in CC models.

Liver Decompensation after Bariatric Surgery in the Absence of Cirrhosis.

PURPOSE: Metabolic dysfunction-associated fatty liver disease-related cirrhosis is possible at the time of bariatric surgery, complicated by further liver decompensation. Hepatic decompensation can also occur in the absence of cirrhosis but the presentation is less clear. METHODS: We analyze the clinical characteristics, histological findings, and management of patients without cirrhosis who developed hepatic decompensation after bariatric surgery in our single tertiary-care hospital. RESULTS: From 2014 to 2019, 6 patients underwent a transvenous liver biopsy for liver decompensation after bariatric surgery. Mean age at diagnosis was 44 years. The time between bariatric surgery and the onset of symptoms varied widely (min. 8 months, max. 17 years). Mean % of weight loss was high at 43%. The clinical presentation was as follows: fatigue and jaundice (5/6), leg edema (3/6), and ascites (1/6). Blood test showed increased transaminases (mean ALT 53 UI/L, mean AST 130 UI/L), bilirubin (mean 6 mg/dL), and INR (mean 1.5) with a low albumin level (mean 27 mg/dL). The hepatic venous pressure gradient was high (mean 10 mmHg). Histology revealed steatosis, hepatocyte ballooning but also portal inflammation with polymorphonuclear cells, and bile duct alterations. Mean fibrosis score was 2. The clinical course was favorable with nutritional support with a mean follow-up of 36 months. CONCLUSION: Liver decompensation in the absence of cirrhosis can occur after bariatric surgery with a highly variable delay. A special histological signature is present with the coexistence of steatosis, bile duct alterations, and portal inflammation. Substantial clinical improvement with appropriate nutritional support seems to be effective.

Muscle fat content is strongly associated with NASH: A longitudinal study in patients with morbid obesity.

BACKGROUND & AIMS: Studies exploring the relationship between muscle fat content and non-alcoholic fatty liver disease (NAFLD) are scarce. Herein, we aimed to evaluate the association of muscle mass and fatty infiltration with biopsy-assessed NAFLD in patients with obesity. METHODS: At inclusion (n = 184) and 12 months after a dietary intervention (n = 15) or bariatric surgery (n = 24), we evaluated NAFLD by liver biopsy, and skeletal muscle mass index (SMI) by CT (CT-SMI) or bioelectrical impedance analysis (BIA-SMI). We developed an index to evaluate absolute fat content in muscle (skeletal muscle fat index [SMFI]) from CT-based psoas muscle density (SMFIPsoas). RESULTS: Muscle mass was higher in patients with NAFLD than in those without (CT-SMI 56.8 ± 9.9 vs. 47.4 ± 6.5 cm2/m2, p <0.0001). There was no association between sarcopenia and non-alcoholic steatohepatitis (NASH). SMFIPsoas was higher in NASH ≥F2 and early NASH F0-1 than in NAFL (78.5 ± 23.6 and 73.1 ± 15.6 vs. 61.2 ± 12.6, p <0.001). A 1-point change in the score for any of the individual cardinal NASH features (i.e. steatosis, inflammation or ballooning) was associated with an increase in SMFIPsoas (all p <0.05). The association between SMFIPsoas and NASH was highly significant even after adjustment for multiple confounders (all p <0.025). After intervention (n = 39), NASH improvement, defined by NAFLD activity score <3 or a 2-point score reduction, was achieved in more than 75% of patients (n = 25 or n = 27, respectively) that had pre-established NASH at inclusion (n = 32) and was associated with a significant decrease in SMFIPsoas (p <0.001). Strikingly, all patients who had ≥11% reduction in SMFIPsoas achieved NASH improvement (14/14, p <0.05). CONCLUSIONS: Muscle fat content, but not muscle mass, is strongly and independently associated with NASH. All individuals who achieved a ≥11% decrease in SMFIPsoas after intervention improved their NASH. These data indicate that muscle fatty infiltration could be a potential marker for (and perhaps a pathophysiological contributor to) NASH. LAY SUMMARY: The fat content in skeletal muscles is highly reflective of the severity of non-alcoholic fatty liver disease (NAFLD) in patients with morbid obesity. In particular, muscle fat content is strongly associated with non-alcoholic steatohepatitis (NASH) and decreases upon NASH improvement. These data indicate that muscle fatty infiltration could be a marker and possible pathophysiological contributor to NASH.

Myosteatosis rather than sarcopenia associates with non-alcoholic steatohepatitis in non-alcoholic fatty liver disease preclinical models.

BACKGROUND: Non-alcoholic fatty liver (NAFL) disease (NAFLD) is the most common chronic liver disease in the world. While most subjects have 'inert' NAFL, a subset will progress to non-alcoholic steatohepatitis (NASH) and its life-threatening complications. A substantial body of literature supports that a low muscle mass, low strength, and/or muscle fatty infiltration (myosteatosis) are associated with NAFLD severity. Here, we evaluated the muscle compartment in NASH preclinical models to decipher the kinetics of muscle alterations in relation with liver disease progression. METHODS: We developed and validated a micro-computed tomography-based methodology to prospectively study skeletal muscle mass and density in muscle and liver (i.e. reflecting fatty infiltration) in a high-throughput and non-invasive manner in three preclinical NAFLD/NASH rodent models: fat aussie (FOZ) mice fed a high-fat diet (FOZ HF), wild-type (WT) mice fed a high-fat high-fructose diet (WT HFF), and WT mice fed a high-fat diet (WT HF). We compared them with WT mice fed a normal diet (WT ND) used as controls. RESULTS: -FOZ HF with fibrosing NASH had sarcopenia characterized by a reduced muscle strength when compared with WT HF and WT HFF with early NASH and WT ND controls (165.2 ± 5.2 g vs. 237.4 ± 11.7 g, 256 ± 5.7 g, and 242.9 ± 9.3 g, respectively, P 60; 0.001). Muscle mass or strength was not lower in FOZ HF, WT HF, and WT HFF with early NASH than in controls. Myosteatosis was present in FOZ HF with fibrosing NASH, but also in FOZ HF, WT HF, and WT HFF with early NASH (muscle density = 0.50 ± 0.02, 0.62 ± 0.02, 0.70 ± 0.05, and 0.75 ± 0.03, respectively, with P 60; 0.001 when compared with respective controls). Myosteatosis degree was strongly correlated with NAFLD activity score (r = -0.87, n = 67, P 60; 0.001). In multivariate analysis, the association between myosteatosis and NASH was independent from homeostatic model assessment of insulin resistance and visceral fat area (P 60; 0.05). Myosteatosis degree powerfully discriminated NASH from benign NAFL and normal liver (area under the receiver operating characteristic = 0.96, n = 67, P 60; 0.001). CONCLUSIONS: Taken together, our data support that there is no sarcopenia in obese mice with early NASH. In contrast, the severity of myosteatosis reflects on hepatocellular damage and inflammation during early NASH development. This observation prompts us to exploit myosteatosis as a novel non-invasive marker of NASH.

Inflammation-induced cholestasis in cancer cachexia.

BACKGROUND: Cancer cachexia is a debilitating metabolic syndrome contributing to cancer death. Organs other than the muscle may contribute to the pathogenesis of cancer cachexia. This work explores new mechanisms underlying hepatic alterations in cancer cachexia. METHODS: We used transcriptomics to reveal the hepatic gene expression profile in the colon carcinoma 26 cachectic mouse model. We performed bile acid, tissue mRNA, histological, biochemical, and western blot analyses. Two interventional studies were performed using a neutralizing interleukin 6 antibody and a bile acid sequestrant, cholestyramine. Our findings were evaluated in a cohort of 94 colorectal cancer patients with or without cachexia (43/51). RESULTS: In colon carcinoma 26 cachectic mice, we discovered alterations in five inflammatory pathways as well as in other pathways, including bile acid metabolism, fatty acid metabolism, and xenobiotic metabolism (normalized enrichment scores of -1.97, -2.16, and -1.34, respectively; all Padj < 0.05). The hepatobiliary transport system was deeply impaired in cachectic mice, leading to increased systemic and hepatic bile acid levels (+1512 ± 511.6 pmol/mg, P = 0.01) and increased hepatic inflammatory cytokines and neutrophil recruitment to the liver of cachectic mice (+43.36 ± 16.01 neutrophils per square millimetre, P = 0.001). Adaptive mechanisms were set up to counteract this bile acid accumulation by repressing bile acid synthesis and by enhancing alternative routes of basolateral bile acid efflux. Targeting bile acids using cholestyramine reduced hepatic inflammation, without affecting the hepatobiliary transporters (e.g. tumour necrosis factor α signalling via NFκB and inflammatory response pathways, normalized enrichment scores of -1.44 and -1.36, all Padj < 0.05). Reducing interleukin 6 levels counteracted the change in expression of genes involved in the hepatobiliary transport, bile acid synthesis, and inflammation. Serum bile acid levels were increased in cachectic vs. non-cachectic cancer patients (e.g. total bile acids, +5.409 ± 1.834 µM, P = 0.026) and were strongly correlated to systemic inflammation (taurochenodeoxycholic acid and C-reactive protein: ρ = 0.36, Padj = 0.017). CONCLUSIONS: We show alterations in bile acid metabolism and hepatobiliary secretion in cancer cachexia. In this context, we demonstrate the contribution of systemic inflammation to the impairment of the hepatobiliary transport system and the role played by bile acids in the hepatic inflammation. This work paves the way to a better understanding of the role of the liver in cancer cachexia.

Marked Increased Production of Acute Phase Reactants by Skeletal Muscle during Cancer Cachexia.

Loss of skeletal muscle mass in cancer cachexia is recognized as a predictor of mortality. This study aimed to characterize the changes in the muscle secretome associated with cancer cachexia to gain a better understanding of the mechanisms involved and to identify secreted proteins which may reflect this wasting process. The changes in the muscle proteome of the C26 model were investigated by label-free proteomic analysis followed by a bioinformatic analysis in order to identify potentially secreted proteins. Multiple reaction monitoring and Western blotting were used to verify the presence of candidate proteins in the circulation. Our results revealed a marked increased muscular production of several acute phase reactants (APR: Haptoglobin, Serine protease inhibitor A3N, Complement C3, Serum amyloid A-1 protein) which are released in the circulation during C26 cancer cachexia. This was confirmed in other models of cancer cachexia as well as in cancer patients. Glucocorticoids and proinflammatory cytokines are responsible for an increased production of APR by muscle cells. Finally, their muscular expressions are strongly positively correlated with body weight loss as well as the muscular induction of atrogens. Our study demonstrates therefore a marked increased production of APR by the muscle in cancer cachexia.

A Novel KRAS Antibody Highlights a Regulation Mechanism of Post-Translational Modifications of KRAS during Tumorigenesis.

KRAS is a powerful oncogene responsible for the development of many cancers. Despite the great progress in understanding its function during the last decade, the study of KRAS expression, subcellular localization, and post-translational modifications remains technically challenging. Accordingly, many facets of KRAS biology are still unknown. Antibodies could be an effective and easy-to-use tool for in vitro and in vivo research on KRAS. Here, we generated a novel rabbit polyclonal antibody that allows immunolabeling of cells and tissues overexpressing KRAS. Cell transfection experiments with expression vectors for the members of the RAS family revealed a preferential specificity of this antibody for KRAS. In addition, KRAS was sensitively detected in a mouse tissue electroporated with an expression vector. Interestingly, our antibody was able to detect endogenous forms of unprenylated (immature) and prenylated (mature) KRAS in mouse organs. We found that KRAS prenylation was increased ex vivo and in vivo in a model of KRASG12D-driven tumorigenesis, which was concomitant with an induction of expression of essential KRAS prenylation enzymes. Therefore, our tool helped us to put the light on new regulations of KRAS activation during cancer initiation. The use of this tool by the RAS community could contribute to discovering novel aspects of KRAS biology.

COVID-19 in diabetic patients: Related risks and specifics of management.

Diabetes is among the most frequently reported comorbidities in patients infected with COVID-19. According to current data, diabetic patients do not appear to be at increased risk of contracting SARS-CoV-2 compared to the general population. On the other hand, diabetes is a risk factor for developing severe and critical forms of COVID-19, the latter requiring admission to an intensive care unit and/or use of invasive mechanical ventilation, with high mortality rates. The characteristics of diabetic patients at risk for developing severe and critical forms of COVID-19, as well as the prognostic impact of diabetes on the course of COVID-19, are under current investigation. Obesity, the main risk factor for incident type 2 diabetes, is more common in patients with critical forms of COVID-19 requiring invasive mechanical ventilation. On the other hand, COVID-19 is usually associated with poor glycemic control and a higher risk of ketoacidosis in diabetic patients. There are currently no recommendations in favour of discontinuing antihypertensive medications that interact with the renin-angiotensin-aldosterone system. Metformin and SGLT2 inhibitors should be discontinued in patients with severe forms of COVID-19 owing to the risks of lactic acidosis and ketoacidosis. Finally, we advise for systematic screening for (pre)diabetes in patients with proven COVID-19 infection.

A sarcoidosis-lymphoma syndrome revealed by hypopituitarism.

SUMMARY: A 26-year-old woman presented with persistent headache and tiredness. Biological investigations disclosed a moderate inflammatory syndrome, low PTH-hypercalcemia and complete anterior hypopituitarism. A magnetic resonance imaging (MRI) of the pituitary gland was performed and revealed a symmetric enlargement with a heterogeneous signal. Ophthalmological examination showed an asymptomatic bilateral anterior and posterior uveitis, and a diagnosis of pituitary sarcoidosis was suspected. As the localization of lymphadenopathies on the fused whole-body FDG-PET/computerized tomography (CT) was not evoking a sarcoidosis in first instance, an excisional biopsy of a left supraclavicular adenopathy was performed showing classic nodular sclerosis Hodgkin's lymphoma (HL). A diagnostic transsphenoidal biopsy of the pituitary gland was proposed for accurate staging of the HL and surprisingly revealed typical granulomatous inflammation secondary to sarcoidosis, leading to the diagnosis of a sarcoidosis-lymphoma syndrome. The co-existence of these diseases constitutes a diagnostic challenge and we emphasize the necessity of exact staging of disease in order to prescribe adequate treatment. LEARNING POINTS: The possibility of a sarcoidosis-lymphoma syndrome, although rare, should be kept in mind during evaluation for lymphadenopathies. In the case of such association, lymphoma usually occurs after sarcoidosis. However, sarcoidosis and lymphoma can be detected simultaneously and development of sarcoidosis in a patient with previous lymphoma has also been reported. An accurate diagnosis of the disease and the respective organ involvements, including biopsy, is necessary in order to prescribe adequate treatment.

Increased Serpina3n release into circulation during glucocorticoid-mediated muscle atrophy.

BACKGROUND: Glucocorticoids (GC) play a major role in muscle atrophy. As skeletal muscle is a secretory organ, characterization of the muscle secretome elicited by muscle atrophy should allow to better understand the cellular mechanisms and to identify circulating biomarkers of this condition. Our project aimed to identify the changes in the muscle secretome associated with GC-induced muscle atrophy and susceptible to translate into circulation. METHODS: We have identified the GC-induced changes in the secretome of C2 C12 muscle cells by proteomic analysis, and then, we have determined how these changes translate into the circulation of mice or human subjects exposed to high concentrations of GC. RESULTS: This approach led us to identify Serpina3n as one of the most markedly secreted protein in response to GC. Our original in vitro results were confirmed in vivo by an increased expression of Serpina3n in skeletal muscle (3.9-fold; P < 0.01) and in the serum (two-fold; P < 0.01) of mice treated with GC. We also observed increased levels of the human orthologue Serpina3 in the serum of Cushing's syndrome patients compared with healthy controls matched for age and sex (n = 9/group, 2.5-fold; P < 0.01). An increase of Serpina3n was also demonstrated in muscle atrophy models mediated by GC such as cancer cachexia (four-fold; P < 0.01), sepsis (12.5-fold; P < 0.001), or diabetes (two-fold; P < 0.01). In contrast, levels of Serpina3n both in skeletal muscle and in the circulation were reduced in several models of muscle hypertrophy induced by myostatin inhibition (P < 0.01). Furthermore, a cluster of data suggests that the regulation of muscle Serpina3n involves mTOR, an essential determinant of the muscle cell size. CONCLUSIONS: Taken together, these data suggest that Serpina3n may represent a circulating biomarker of muscle atrophy associated to GC and, broadly, a reflection of dynamic changes in muscle mass.

Twist1 Activation in Muscle Progenitor Cells Causes Muscle Loss Akin to Cancer Cachexia.

Cancer cachexia is characterized by extreme skeletal muscle loss that results in high morbidity and mortality. The incidence of cachexia varies among tumor types, being lowest in sarcomas, whereas 90% of pancreatic ductal adenocarcinoma (PDAC) patients experience severe weight loss. How these tumors trigger muscle depletion is still unfolding. Serendipitously, we found that overexpression of Twist1 in mouse muscle progenitor cells, either constitutively during development or inducibly in adult animals, caused severe muscle atrophy with features reminiscent of cachexia. Using several genetic mouse models of PDAC, we detected a marked increase in Twist1 expression in muscle undergoing cachexia. In cancer patients, elevated levels of Twist1 are associated with greater degrees of muscle wasting. Finally, both genetic and pharmacological inactivation of Twist1 in muscle progenitor cells afforded substantial protection against cancer-mediated cachexia, which translated into meaningful survival benefits, implicating Twist1 as a possible target for attenuating muscle cachexia in cancer patients.

Increased gut permeability in cancer cachexia: mechanisms and clinical relevance.

Intestinal disorders often occur in cancer patients, in association with body weight loss, and this alteration is commonly attributed to the chemotherapy. Here, using a mouse model of cancer cachexia induced by ectopic transplantation of C26 cancer cells, we discovered a profound alteration in the gut functions (gut permeability, epithelial turnover, gut immunity, microbial dysbiosis) independently of any chemotherapy. These alterations occurred independently of anorexia and were driven by interleukin 6. Gut dysfunction was found to be resistant to treatments with an anti-inflammatory bacterium (Faecalibacterium prausnitzii) or with gut peptides involved in intestinal cell renewal (teduglutide, a glucagon-like peptide 2 analogue). The translational value of our findings was evaluated in 152 colorectal and lung cancer patients with or without cachexia. The serum level of the lipopolysaccharide-binding protein, often presented as a reflection of the bacterial antigen load, was not only increased in cachectic mice and cancer patients, but also strongly correlated with the serum IL-6 level and predictive of death and cachexia occurrence in these patients. Altogether, our data highlight profound alterations of the intestinal homeostasis in cancer cachexia occurring independently of any chemotherapy and food intake reduction, with potential relevance in humans. In addition, we point out the lipopolysaccharide-binding protein as a new biomarker of cancer cachexia related to gut dysbiosis.

Circulating Activin A predicts survival in cancer patients.

BACKGROUND: Several experimental evidences pinpoint the possible role of Activin A (ActA) as a driver of cancer cachexia. Supporting this hypothesis, we showed recently that human cancer cachexia is associated with high ActA levels. Moreover, ActA levels were correlated with body weight loss and skeletal muscle density, two prognostic factors in cancer patients. Our goal was therefore to investigate the value of ActA to predict survival in cancer patients. METHODS: Patients with colorectal or lung cancer were prospectively enrolled at the time of diagnosis or relapse between January 2012 and March 2014. At baseline, patients had clinical, nutritional, and functional assessment. Body composition and skeletal muscle density were measured by CT scan, and plasma ActA concentrations were determined. Overall survival (OS) was analysed since inclusion to 24 months later. RESULTS: Survival data were available for 149 patients out of 152. Patients with high ActA (≥408 pg/mL) had lower OS than those with low levels, regardless the type of cancer (OS in colorectal cancer, 50% vs. 79%, P < 0.05; and in lung cancer, 27% vs. 67%, P = 0.001). The multivariable analysis confirmed the prognostic value of ActA independently of tumour stage or inflammatory markers, particularly in lung cancer. Low muscularity was also an independent prognostic factor. CONCLUSIONS: Our study demonstrates that high ActA level is an independent prognosis factor of survival in cancer patients. More than a basic marker of the severity of the neoplastic disease or of the inflammatory process, ActA seems to influence survival by contributing to the development of cachexia and loss of skeletal muscle mass.

Biomarkers of cancer cachexia.

Cachexia is a complex multifactorial syndrome, characterized by loss of skeletal muscle and fat mass, which affects the majority of advanced cancer patients and is associated with poor prognosis. Interestingly, reversing muscle loss in animal models of cancer cachexia leads to prolong survival. Therefore, detecting cachexia and maintaining muscle mass represent a major goal in the care of cancer patients. However, early diagnosis of cancer cachexia is currently limited for several reasons. Indeed, cachexia development is variable according to tumor and host characteristics. In addition, safe, accessible and non-invasive tools to detect skeletal muscle atrophy are desperately lacking in clinical practice. Finally, the precise molecular mechanisms and the key players involved in cancer cachexia remain poorly characterized. The need for an early diagnosis of cancer cachexia supports therefore the quest for a biomarker that might reflect skeletal muscle atrophy process. Current research offers different promising ways to identify such a biomarker. Initially, the quest for a biomarker of cancer cachexia has mostly focused on mediators of muscle atrophy, produced by both tumor and host, in an attempt to define new therapeutic approaches. In another hand, molecules released by the muscle into the circulation during the atrophy process have been also considered as potential biomarkers. More recently, several "omics" studies are emerging to identify new muscular or circulating markers of cancer cachexia. Some genetic markers could also contribute to identify patients more susceptible to develop cachexia. This article reviews our current knowledge regarding potential biomarkers of cancer cachexia.

Role of IGF-I in follistatin-induced skeletal muscle hypertrophy.

Follistatin, a physiological inhibitor of myostatin, induces a dramatic increase in skeletal muscle mass, requiring the type 1 IGF-I receptor/Akt/mTOR pathway. The aim of the present study was to investigate the role of IGF-I and insulin, two ligands of the IGF-I receptor, in the follistatin hypertrophic action on skeletal muscle. In a first step, we showed that follistatin increases muscle mass while being associated with a downregulation of muscle IGF-I expression. In addition, follistatin retained its full hypertrophic effect toward muscle in hypophysectomized animals despite very low concentrations of circulating and muscle IGF-I. Furthermore, follistatin did not increase muscle sensitivity to IGF-I in stimulating phosphorylation of Akt but, surprisingly, decreased it once hypertrophy was present. Taken together, these observations indicate that increased muscle IGF-I production or sensitivity does not contribute to the muscle hypertrophy caused by follistatin. Unlike low IGF-I, low insulin, as obtained by streptozotocin injection, attenuated the hypertrophic action of follistatin on skeletal muscle. Moreover, the full anabolic response to follistatin was restored in this condition by insulin but also by IGF-I infusion. Therefore, follistatin-induced muscle hypertrophy requires the activation of the insulin/IGF-I pathway by either insulin or IGF-I. When insulin or IGF-I alone is missing, follistatin retains its full anabolic effect, but when both are deficient, as in streptozotocin-treated animals, follistatin fails to stimulate muscle growth.