Project description:Hepatocellular carcinoma (HCC) can have viral or non-viral causes1-5. Non-alcoholic steatohepatitis (NASH) is an important driver of HCC. Immunotherapy has been approved for treating HCC, but biomarker-based stratification of patients for optimal response to therapy is an unmet need6,7. Here we report the progressive accumulation of exhausted, unconventionally activated CD8+PD1+ T cells in NASH-affected livers. In preclinical models of NASH-induced HCC, therapeutic immunotherapy targeted at programmed death-1 (PD1) expanded activated CD8+PD1+ T cells within tumours but did not lead to tumour regression, which indicates that tumour immune surveillance was impaired. When given prophylactically, anti-PD1 treatment led to an increase in the incidence of NASH-HCC and in the number and size of tumour nodules, which correlated with increased hepatic CD8+PD1+CXCR6+, TOX+, and TNF+ T cells. The increase in HCC triggered by anti-PD1 treatment was prevented by depletion of CD8+ T cells or TNF neutralization, suggesting that CD8+ T cells help to induce NASH-HCC, rather than invigorating or executing immune surveillance. We found similar phenotypic and functional profiles in hepatic CD8+PD1+ T cells from humans with NAFLD or NASH. A meta-analysis of three randomized phase III clinical trials that tested inhibitors of PDL1 (programmed death-ligand 1) or PD1 in more than 1,600 patients with advanced HCC revealed that immune therapy did not improve survival in patients with non-viral HCC. In two additional cohorts, patients with NASH-driven HCC who received anti-PD1 or anti-PDL1 treatment showed reduced overall survival compared to patients with other aetiologies. Collectively, these data show that non-viral HCC, and particularly NASH-HCC, might be less responsive to immunotherapy, probably owing to NASH-related aberrant T cell activation causing tissue damage that leads to impaired immune surveillance. Our data provide a rationale for stratification of patients with HCC according to underlying aetiology in studies of immunotherapy as a primary or adjuvant treatment.
Project description:Obesity is a major driver of cancer, especially hepatocellular carcinoma (HCC). The prevailing view is that non-alcoholic steatohepatitis (NASH) and fibrosis or cirrhosis are required for HCC in obesity. Here, we report that NASH and fibrosis and HCC in obesity can be dissociated. We show that the oxidative hepatic environment in obesity inactivates the STAT-1 and STAT-3 phosphatase T cell protein tyrosine phosphatase (TCPTP) and increases STAT-1 and STAT-3 signaling. TCPTP deletion in hepatocytes promoted T cell recruitment and ensuing NASH and fibrosis as well as HCC in obese C57BL/6 mice that normally do not develop NASH and fibrosis or HCC. Attenuating the enhanced STAT-1 signaling prevented T cell recruitment and NASH and fibrosis but did not prevent HCC. By contrast, correcting STAT-3 signaling prevented HCC without affecting NASH and fibrosis. TCPTP-deletion in hepatocytes also markedly accelerated HCC in mice treated with a chemical carcinogen that promotes HCC without NASH and fibrosis. Our studies reveal how obesity-associated hepatic oxidative stress can independently contribute to the pathogenesis of NASH, fibrosis, and HCC.
Project description:Nonalcoholic fatty liver disease (NAFLD) is the leading contributor to the global burden of chronic liver diseases. The phenotypic umbrella of NAFLD spans from simple and reversible steatosis to nonalcoholic steatohepatitis (NASH), which may worsen into cirrhosis and hepatocellular carcinoma (HCC). Notwithstanding, HCC may develop also in the absence of advanced fibrosis, causing a delayed time in diagnosis as a consequence of the lack of HCC screening in these patients. The precise event cascade that may precipitate NASH into HCC is intricate and it entails diverse triggers, encompassing exaggerated immune response, endoplasmic reticulum (ER) and oxidative stress, organelle derangement and DNA aberrancies. All these events may be accelerated by both genetic and environmental factors. On one side, common and rare inherited variations that affect hepatic lipid remodeling, immune microenvironment and cell survival may boost the switching from steatohepatitis to liver cancer, on the other, diet-induced dysbiosis as well as nutritional and behavioral habits may furtherly precipitate tumor onset. Therefore, dietary and lifestyle interventions aimed to restore patients' health contribute to counteract NASH progression towards HCC. Even more, the combination of therapeutic strategies with dietary advice may maximize benefits, with the pursuit to improve liver function and prolong survival.
Project description:Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver and the third-leading cause of cancer-related mortality. Currently, the global burden of nonalcoholic fatty liver disease (NAFLD) has dramatically overcome both viral and alcohol hepatitis, thus becoming the main cause of HCC incidence. NAFLD pathogenesis is severely influenced by lifestyle and genetic predisposition. Mitochondria are highly dynamic organelles that may adapt in response to environment, genetics and epigenetics in the liver ("mitochondrial plasticity"). Mounting evidence highlights that mitochondrial dysfunction due to loss of mitochondrial flexibility may arise before overt NAFLD, and from the early stages of liver injury. Mitochondrial failure promotes not only hepatocellular damage, but also release signals (mito-DAMPs), which trigger inflammation and fibrosis, generating an adverse microenvironment in which several hepatocytes select anti-apoptotic programs and mutations that may allow survival and proliferation. Furthermore, one of the key events in malignant hepatocytes is represented by the remodeling of glucidic-lipidic metabolism combined with the reprogramming of mitochondrial functions, optimized to deal with energy demand. In sum, this review will discuss how mitochondrial defects may be translated into causative explanations of NAFLD-driven HCC, emphasizing future directions for research and for the development of potential preventive or curative strategies.
Project description:ObjectivesThe precipitous increase in nonalcoholic steatohepatitis (NASH) is accompanied by a dramatic increase in the incidence of NASH-related hepatocellular carcinoma (HCC). HCC in NASH has a higher propensity to arise without pre-existing cirrhosis compared with other chronic liver diseases.MethodsTo identify the potential links between liver and gut in NASH-related hepatocarcinogenesis, we compared the gut microbiota and mediators of bile acid (BA) signaling in the absence or presence of cirrhosis through the analysis of stool and serum samples from patients with NASH non-HCC and NASH-HCC and healthy volunteers.ResultsSerum levels of total and individual BA were higher in NASH compared with healthy controls. Furthermore, serum levels of the primary conjugated BAs glycine-conjugated cholic acid, taurine-conjugated cholic acid, glycine-conjugated chenodeoxycholic acid, and taurine-conjugated chenodeoxycholic acid were significantly increased in cirrhotic vs noncirrhotic patients, independent of the occurrence of HCC. By contrast, serum FGF19 levels were higher in patients with NASH-HCC and associated with tumor markers as well as an attenuation of BA synthesis. Specific alterations in the gut microbiome were found for several bacteria involved in the BA metabolism including Bacteroides and Lactobacilli. Specifically, the abundance of Lactobacilli was associated with progressive disease, serum BA levels, and liver injury in NASH and NASH-HCC.DiscussionHere, we demonstrate a clear association of the altered gut microbiota and primary conjugated BA composition in cirrhotic and noncirrhotic patients with NASH-HCC. Microbiota-associated alterations in BA homeostasis and farnesoid X receptor signaling, via FGF19, might thus contribute to fibrogenesis, liver injury, and tumorigenesis in NASH-HCC.
Project description:BackgroundThe block phase in the swimming start requires a quick reaction to the starting signal and a large take-off velocity that is primarily horizontal in direction. Due to the principle of specificity of training, there is a potential benefit of performing a greater proportion of horizontal force production exercises in a swimmers' dry-land resistance training sessions. Therefore, the purpose of this pilot study was to provide an insight into the effects of a horizontal- (HF) vs vertical-force (VF) training intervention on swim start performance.MethodsEleven competitive swimmers (six males (age 20.9 ± 1.8 years, body mass 77.3 ± 9.7 kg, height 1.78 ± 0.05 m) and five females (age 21.4 ± 2.0 years, body mass 67.5 ± 7.4 kg, height 1.69 ± 0.05 m)) completed 2 weekly sessions of either a horizontal- or vertical-force focused resistance training programme for 8 weeks. Squat jump force-time characteristics and swim start kinetic and kinematic parameters were collected pre- and post-intervention.ResultsAcross the study duration, the swimmers completed an average of nine swimming sessions per week with an average weekly swim volume of 45.5 ± 17.7 km (HF group) and 53 ± 20.0 km (VF group), but little practice of the swim start per week (n = 9). Within-group analyses indicated a significant increase in predicted one repetition maximum (1RM) hip thrust strength in the HF group, as well as significant increases in grab resultant peak force but reductions in resultant peak force of the block phase for the VF group. No significant between-group differences in predicted 1RM hip thrust and back squat strength, squat jump force-time and swim start performance measures were observed after 8 weeks of training. Significant correlations in the change scores of five block kinetic variables to time to 5 m were observed, whereby increased block kinetic outputs were associated with a reduced time to 5 m. This may be indicative of individual responses to the different training programmes.DiscussionThe results of this current study have been unable to determine whether a horizontal- or vertical-force training programme enhances swim start performance after an 8-week training intervention. Some reasons for the lack of within and between group effects may reflect the large volume of concurrent training and the relative lack of any deliberate practice of the swim start. Larger samples and longer training duration may be required to determine whether significant differences occur between these training approaches. Such research should also look to investigate how a reduction in the concurrent training loads and/or an increase in the deliberate practice of the swim start may influence the potential changes in swim start performance.
Project description:A comprehensive screening of site-specific N-glycopeptides in serum haptoglobin (Hp), a reporter molecule for aberrant glycosylation in HCC, has been performed to characterize glycopeptide markers for NASH-related HCCs.
Project description:Obesity increases the risk for nonalcoholic steatohepatitis (NASH) and hepatocarcinogenesis. However, the underlying mechanisms involved in the disease process remain unclear. Recently, we have developed a transgenic obese mouse model (Mito-Ob) by prohibitin mediated mitochondrial remodeling in adipocytes. The Mito-Ob mice develop obesity in a sex-neutral manner, but obesity-associated adipose inflammation and metabolic dysregulation in a male sex-specific manner. Here we report that with aging, the male Mito-Ob mice spontaneously develop obesity-linked NASH and hepatocellular carcinoma (HCC). In contrast, the female Mito-Ob mice maintained normal glucose and insulin levels and did not develop NASH and HCC. The anti-inflammatory peptide ghrelin was significantly upregulated in the female mice and down regulated in the male mice compared with respective control mice. In addition, a reduction in the markers of mitochondrial content and function was found in the liver of male Mito-Ob mice with NASH/HCC development. We found that ERK1/2 signaling was significantly upregulated whereas STAT3 signaling was significantly down regulated in the tumors from Mito-Ob mice. These data provide a proof-of-concept that the metabolic and inflammatory status of the adipose tissue and their interplay at the systemic and hepatic level play a central role in the pathogenesis of obesity-linked NASH and HCC.
Project description:A peculiar role for oxidative stress in non-alcoholic fatty liver disease (NAFLD) and its transition to the inflammatory complication non-alcoholic steatohepatitis (NASH), as well as in its threatening evolution to hepatocellular carcinoma (HCC), is supported by numerous experimental and clinical studies. NADPH oxidases (NOXs) are enzymes producing reactive oxygen species (ROS), whose abundance in liver cells is closely related to inflammation and immune responses. Here, we reviewed recent findings regarding this topic, focusing on the role of NOXs in the different stages of fatty liver disease and describing the current knowledge about their mechanisms of action. We conclude that, although there is a consensus that NOX-produced ROS are toxic in non-neoplastic conditions due to their role in the inflammatory vicious cycle sustaining the transition of NAFLD to NASH, their effect is controversial in the neoplastic transition towards HCC. In this regard, there are indications of a differential effect of NOX isoforms, since NOX1 and NOX2 play a detrimental role, whereas increased NOX4 expression appears to be correlated with better HCC prognosis in some studies. Further studies are needed to fully unravel the mechanisms of action of NOXs and their relationships with the signaling pathways modulating steatosis and liver cancer development.