Emerging risk factors for nonalcoholic fatty liver disease associated hepatocellular carcinoma

Metabolic Dysfunction-Associated Steatohepatitis and Progression to Hepatocellular Carcinoma: A Literature Review

The prevalence of metabolic-associated fatty liver disease (MAFLD) is increasing globally due to factors such as urbanization, obesity, poor nutrition, sedentary lifestyles, healthcare accessibility, diagnostic advancements, and genetic influences. Research on MAFLD and HCC risk factors, pathogenesis, and biomarkers has been conducted through a narrative review of relevant studies, with a focus on PubMed and Web of Science databases and exclusion criteria based on article availability and language. Steatosis marks the early stage of MASH advancement, commonly associated with factors of metabolic syndrome such as obesity and type 2 diabetes. Various mechanisms, including heightened lipolysis, hepatic lipogenesis, and consumption of high-calorie diets, contribute to the accumulation of lipids in the liver. Insulin resistance is pivotal in the development of steatosis, as it leads to the release of free fatty acids from adipose tissue. Natural compounds hold promise in regulating lipid metabolism and inflammation to combat these conditions. Liver fibrosis serves as a significant predictor of MASH progression and HCC development, underscoring the need to target fibrosis in treatment approaches. Risk factors for MASH-associated HCC encompass advanced liver fibrosis, older age, male gender, metabolic syndrome, genetic predispositions, and dietary habits, emphasizing the requirement for efficient surveillance and diagnostic measures. Considering these factors, it is important for further studies to determine the biochemical impact of these risk factors in order to establish targeted therapies that can prevent the development of HCC or reduce progression of MASH, indirectly decreasing the risk of HCC.

Evaluation of risk factors for non-alcoholic fatty liver disease in India: A systematic review and meta-analysis

INTRODUCTION

NAFLD is emerging as an important cause of liver disease in India. It is estimated that 16-32% of general population in India (nearly 120 million) has NAFLD.

OBJECTIVE

This study aimed to identify the risk factors of NAFLD and to identify the association of lifestyle (dietary and physical activity), genetic, and environmental factors with NAFLD in India.

MATERIALS AND METHODS

A systematic literature search was conducted using an international electronic database: PubMed (MEDLINE) and Google Scholar from the date of inception 31st March 2021 to 28th September 2021. We included studies examining patients with NAFLD: Adults above 18 years of age. Studies with or without a control population were both eligible. The studies with a diagnosis of NAFLD based solely on abnormal liver tests were excluded. We tried to get unpublished data but they were not of the quality of inclusion. Meta-analysis was performed using the software STATA 14.2 (StataCorp, College Station, TX, USA). For each of the studies, the standard error was calculated using the reported number of outcomes and the sample size. A forest plot was used to graphically represent the study-specific and pooled prevalence estimates for overall and subgroup analysis.

RESULTS

In a systematic review and meta-analysis of 8 studies including data from over 1800 individuals, we found that among components of lipid profile, LDL and HDL had a negative effects on NAFLD while triglycerides had a positive effect on NAFLD.

CONCLUSION

Type 2 Diabetes Mellitus, Hypertension, and Obesity were the potential risk factors for NAFLD but the evidence generated was only from single studies.

Predictive Algorithm for Hepatic Steatosis Detection Using Elastography Data in the Veterans Affairs Electronic Health Records

BACKGROUND AND AIMS

Nonalcoholic fatty liver disease (NAFLD) has reached pandemic proportions. Early detection can identify at-risk patients who can be linked to hepatology care. The vibration-controlled transient elastography (VCTE) controlled attenuation parameter (CAP) is biopsy validated to diagnose hepatic steatosis (HS). We aimed to develop a novel clinical predictive algorithm for HS using the CAP score at a Veterans' Affairs hospital.

METHODS

We identified 403 patients in the Greater Los Angeles VA Healthcare System with valid VCTEs during 1/2018-6/2020. Patients with alcohol-associated liver disease, genotype 3 hepatitis C, any malignancies, or liver transplantation were excluded. Linear regression was used to identify predictors of NAFLD. To identify a CAP threshold for HS detection, receiver operating characteristic analysis was applied using liver biopsy, MRI, and ultrasound as the gold standards.

RESULTS

The cohort was racially/ethnically diverse (26% Black/African American; 20% Hispanic). Significant positive predictors of elevated CAP score included diabetes, cholesterol, triglycerides, BMI, and self-identifying as Hispanic. Our predictions of CAP scores using this model strongly correlated (r = 0.61, p < 0.001) with actual CAP scores. The NAFLD model was validated in an independent Veteran cohort and yielded a sensitivity of 82% and specificity 83% (p < 0.001, 95% CI 0.46-0.81%). The estimated optimal CAP for our population cut-off was 273.5 dB/m, resulting in AUC = 75.5% (95% CI 70.7-80.3%).

CONCLUSION

Our HS predictive algorithm can identify at-risk Veterans for NAFLD to further risk stratify them by non-invasive tests and link them to sub-specialty care. Given the biased referral pattern for VCTEs, future work will need to address its applicability in non-specialty clinics. Proposed clinical algorithm to identify patients at-risk for NAFLD prior to fibrosis staging in Veteran.

Lipophilic statins inhibit YAP coactivator transcriptional activity in HCC cells through Rho-mediated modulation of actin cytoskeleton

Hepatocellular carcinoma (HCC) is the third leading cause of liver-related death. Lipophilic statins have been associated with a decrease in HCC incidence, raising the possibility of their use as chemoprevention agents. The Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) have emerged as an important pro-oncogenic mechanism in HCC. Statins modulate YAP/TAZ in other solid tumors, but few studies have assessed their mechanisms in HCC. We aimed to delineate how lipophilic statins regulate YAP protein localization by interrogating the mevalonate pathway in a stepwise manner using pharmacological and genetical approaches in HCC cells. Huh7 and Hep3B HCC cells were treated with the lipophilic statins cerivastatin and atorvastatin. YAP protein localization was determined using quantitative immunofluorescence (IF) imaging. The gene expression of CTGF and CYR61, known YAP/TEA-domain DNA-binding factor (TEAD)-regulated genes, was measured using quantitative real-time PCR. Rescue experiments were conducted using metabolites of the mevalonate pathway including mevalonic acid and geranylgeranyl pyrophosphate (GG-PP). The cellular cytoskeleton was assessed using F-actin IF staining. YAP protein was extruded from the nucleus to the cytoplasm with statin treatment. Consistently, CTGF and CYR61 mRNA expression significantly decreased with statins. Cytoskeletal structure was also compromised with statins. Gene expression, YAP protein localization, and cytoskeletal structure were all restored to baseline with exogenous GG-PP but not with other metabolites of the mevalonate pathway. Direct Rho GTPase inhibitor treatment mirrored the statin effects on YAP. YAP protein localization is regulated by lipophilic statins via Rho GTPases, causing cytoskeletal structural changes and is independent of cholesterol metabolites.NEW & NOTEWORTHY Statins are widely used for the treatment of cardiovascular diseases. Recently, their use has been associated with a decrease in the incidence of hepatocellular carcinoma (HCC); however, their mechanism(s) has remained elusive. In this study, we delineate the mechanism by which statins affect the Yes-associated protein (YAP), which has emerged as a key oncogenic pathway in HCC. We investigate each step of the mevalonate pathway and demonstrate that statins regulate YAP via Rho GTPases.

Risk factors and diagnostic biomarkers for nonalcoholic fatty liver disease-associated hepatocellular carcinoma: Current evidence and future perspectives

High rates of excessive calorie intake diets and sedentary lifestyles have led to a global increase in nonalcoholic fatty liver disease (NAFLD). As a result, this condition has recently become one of the leading causes of hepatocellular carcinoma (HCC). Furthermore, the incidence of NAFLD-associated HCC (NAFLD-HCC) is expected to increase in the near future. Advanced liver fibrosis is the most common risk factor for NAFLD-HCC. However, up to 50% of NAFLD-HCC cases develop without underlying liver cirrhosis. Epidemiological studies have revealed many other risk factors for this condition; including diabetes, other metabolic traits, obesity, old age, male sex, Hispanic ethnicity, mild alcohol intake, and elevated liver enzymes. Specific gene variants, such as single-nucleotide polymorphisms of patatin-like phospholipase domain 3, transmembrane 6 superfamily member 2, and membrane-bound O-acyl-transferase domain-containing 7, are also associated with an increased risk of HCC in patients with NAFLD. This clinical and genetic information should be interpreted together for accurate risk prediction. Alpha-fetoprotein (AFP) is the only biomarker currently recommended for HCC screening. However, it is not sufficiently sensitive in addressing this diagnostic challenge. The GALAD score can be calculated based on sex, age, lectin-bound AFP, AFP, and des-carboxyprothrombin and is reported to show better diagnostic performance for HCC. In addition, emerging studies on genetic and epigenetic biomarkers have also yielded promising diagnostic potential. However, further research is needed to establish an effective surveillance program for the early diagnosis of NAFLD-HCC.

Glucose Intolerance and Cancer Risk: A Community-Based Prospective Cohort Study in Shanghai, China

Background

Cancer becomes the leading cause of premature death in China. Primary objective of this study was to determine the major risk factors especially glucose intolerance for cancer prophylaxis.

Methods

A cluster sampling method was applied to enroll 10,657 community-based adults aged 15-92 years in Shanghai, China in 2013. A structured questionnaire and physical examination were applied in baseline survey. Prediabetes was diagnosed using 75-g oral glucose tolerance test. After excluding 1433 subjects including 224 diagnosed with cancer before and 1 year after baseline survey, the remaining 9,224 subjects were followed-up to December 31, 2020.

Results

A total of 502 new cancer cases were diagnosed. The cancer incidence was 10.29, 9.20, and 5.95/1,000 person-years in diabetes patients, those with prediabetes, and healthy participants, respectively (p<0.001). The multivariate Cox regression analysis indicated that age, prediabetes and diabetes, were associated with an increased risk of cancer in those <65 years, the hazard ratios (95% confidence interval) for prediabetes and diabetes were, 1.49(1.09-2.02) and 1.51(1.12-2.02), respectively. Glucose intolerance (prediabetes and diabetes) were associated with increased risks of stomach cancer, colorectal cancer, and kidney cancer in those <65 years. Anti-diabetic medications reduced the risk of cancer caused by diabetes. The multivariate Cox analysis showed that age, male, <9 years of education, and current smoking were associated with increased risks of cancer in those ≥65 years independently.

Conclusions

Glucose intolerance is the prominent cancer risk factor in adults <65 years. Lifestyle intervention and medications to treat glucose intolerance help prevent cancer in this population.

Chronic cadmium exposure at environmental-relevant level accelerates the development of hepatotoxicity to hepatocarcinogenesis

Cadmium (Cd) is an environmental heavy metal with long biological half-time and adverse health effects. The long-term toxicity of Cd at low levels remains to be elucidated. Here, we investigated the impact of dietary Cd intake at environmental doses in the full disease cycle from liver injury, fibrosis, inflammation to cancer progression in mouse models and in vitro. We found that chronic low-dose Cd exposure promoted the hepatotoxicity and hepato-pathogenesis in normal and CCl₄ mouse models. Cd enhanced liver injury and accelerated liver fibrosis, a key risk factor for cirrhosis and liver cancer, featured as up-regulation of fibrosis-related markers (TGF-β1, collagen-1, and TIMP1) and activation of hepatic stellate cells. Consistently, Cd increased the inflammation and the infiltration of macrophages and dendritic cells in liver. At late stage, the angiogenetic factors, VEGF and CD34, were elevated, indicating abnormal angiogenesis. At the end of treatment, Cd promoted CCl₄-induced liver cancer formation, including incidence, tumor number and size. These effects were more pronounced in male mice than that in females. The promoting-effects of Cd on fibrosis and angiogenesis were further validated in hepatic stellate cells and liver sinusoidal endothelial cells. PPAR and ERBB signaling pathways were identified as the potential pathways to promote the toxicity of chronic Cd exposure. These findings provide a better understanding about the long-term influence of environmental Cd spanning the entire precancerous lesions-to-cancer formation cycle.

Metabolic Spectrum of Liver Failure in Type 2 Diabetes and Obesity: From NAFLD to NASH to HCC

Liver disease is the spectrum of liver damage ranging from simple steatosis called as nonalcoholic fatty liver disease (NAFLD) to hepatocellular carcinoma (HCC). Clinically, NAFLD and type 2 diabetes coexist. Type 2 diabetes contributes to biological processes driving the severity of NAFLD, the primary cause for development of chronic liver diseases. In the last 20 years, the rate of non-viral NAFLD/NASH-derived HCC has been increasing rapidly. As there are currently no suitable drugs for treatment of NAFLD and NASH, a class of thiazolidinediones (TZDs) drugs for the treatment of type 2 diabetes is sometimes used to improve liver failure despite the risk of side effects. Therefore, diagnosis, prevention, and treatment of the development and progression of NAFLD and NASH are important issues. In this review, we will discuss the pathogenesis of NAFLD/NASH and NAFLD/NASH-derived HCC and the current promising pharmacological therapies of NAFLD/NASH. Further, we will provide insights into "adipose-derived adipokines" and "liver-derived hepatokines" as diagnostic and therapeutic targets from NAFLD to HCC.

The Role of Gut Microbiota in Duodenal-Jejunal Bypass Surgery-Induced Improvement of Hepatic Steatosis in HFD-Fed Rats

Bariatric surgery including duodenal-jejunal bypass surgery (DJB) improves insulin sensitivity and reduces obesity-associated inflammation. However, the underlying mechanism for such an improvement is still incompletely understood. Our objective was to investigate the role of the gut microbiota in DJB-associated improvement of hepatic steatosis in high fat diet (HFD)-fed rats. To study this, hepatic steatosis was induced in male adult Sprague-Dawley rats by feeding them with a 60% HFD. At 8 weeks after HFD feeding, the rats were subjected to either DJB or sham operation. HFD was resumed 1 week after the surgery for 3 more weeks. In additional groups of animals, feces were collected from HFD-DJB rats at 2 weeks after DJB. These feces were then transplanted to HFD-fed rats without DJB at 8 weeks after HFD feeding. Hepatic steatosis and fecal microbiota were analyzed at 4 weeks after surgery or fecal transplantation. Our results showed that DJB alleviated hepatic steatosis in HFD-fed rats. Fecal microbiota analysis showed that HFD-fed and standard diet-fed rats clustered differently. DJB induced substantial compositional changes in the gut microbiota. The fecal microbiota of HFD-fed rats received fecal transplant from DJB rats overlapped with that of HFD-DJB rats. Treatment of rats with HFD-induced liver lesions by fecal transplant from DJB-operated HFD-fed rats also attenuated hepatic steatosis. Thus, alterations in the gut microbiota after DJB surgery are sufficient to attenuate hepatic steatosis in HFD-fed rats. Targeting the gut microbiota could be a promising approach for preventing or treating human NAFLD.