Serum cell death biomarker mirrors liver cancer regression after transarterial chemoembolisation

Cytokeratin 18 in nonalcoholic fatty liver disease: value and application

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is a common metabolism-related disease worldwide. Although studies have shown that some medications may be effective for treating NAFLD, they do not satisfy the medical requirements, and lifestyle changes are the most basic strategy. Thus, early detection of NAFLD and timely lifestyle interventions are highly important.

AREAS COVERED

The traditional diagnostic methods for NAFLD are limited by accuracy, cost, and security issues. Cytokeratin 18 (CK18), which is a marker of apoptosis and overall cell death, is an excellent biomarker for NAFLD. Liver fat accumulation in NAFLD triggers the activation of caspases, which increases the CK18 cleavage and its release into the blood. CK18 can help diagnose different stages of NAFLD, especially the nonalcoholic steatohepatitis (NASH) stage. In evaluating the efficacy of the NAFLD treatment and predicting the risk of NAFLD-related diseases, CK18 plays a significant role.

EXPERT OPINION

CK18 can non-invasively monitor the pathological conditions of NAFLD patients and provide new hope for the early diagnosis of NAFLD. Adding CK18 to the NAFLD diagnostic criteria that are widely used in clinical settings may be efficient for the detection of NAFLD and early effective intervention.

The prognostic potential of fragmented CK18 serum levels in HCC patients reflecting disease progression and overall hepatocyte damage

Background

Fragmented cytokeratin 18 (fCK18) is released from damaged hepatocytes undergoing apoptosis and is recognized as a liver condition biomarker. We have developed a highly sensitive serum fCK18 CLEIA and reported that serum levels of this caspase-derived protein were significantly associated with hepatocyte ballooning, thus assisting in the accurate diagnosis of nonalcoholic steatohepatitis (NASH). We aim to investigate serum fCK18 levels in a variety of chronic liver diseases and to explore its potential as a prognostic marker of survival in hepatocellular carcinoma (HCC) patients.

Methods

Serum fCK18 levels were measured using a highly sensitive CLEIA in 497 chronic liver disease patients (297 outpatients and 200 hospitalized with HCC).

Results

In 497 chronic liver disease patients, serum fCK18 levels were significantly correlated with overall liver condition, including ALT, FIB-4 index and albumin-bilirubin (ALBI) score and were significantly increased in patients with HCC. In 200 HCC patients, serum fCK18 levels were significantly correlated with alpha-fetoprotein (AFP) and des-gamma-carboxy prothrombin (DCP), and were significantly associated with HCC stage, whereas FIB-4 index and ALBI score were not changed based on HCC stage. The Survival group had significantly lower levels of serum fCK18, AFP, DCP, FIB-4 index and ALBI score. A ROC analysis yield area under the curve (AUC) value of 0.728 for serum fCK18 is a significantly high value when compared to AUC measurements for other factors. Notably, AUROC values for serum fCK18 levels were constant in the short- and long-term by time-dependent ROC analysis for the prediction of HCC patient survival. HCC patients with serum fCK18 measured at < 1.15 ng/mL, AFP < 7.7 ng/mL, DCP < 133 mAU/mL, ALBI score < -2.97 or FIB-4 index < 6.4 had significantly longer rates of survival when compared to patients with values exceeding these thresholds. Serum fCK18 (HR, 3.5; P < 0.0001), DCP (HR, 3.2; P < 0.0001) and Barcelona Clinic Liver Cancer (BCLC) (HR, 2.4; P = 0.001) values were independent predictors of patient survival. [Conclusion] Serum fCK18 levels reflect overall liver function, the level of liver fibrosis and the progression of HCC, and are a potential predictor of survival in HCC patients.

Non-invasive diagnosis of nonalcoholic fatty liver disease in patients with type 2 diabetes

Liver disease has emerged as a significant cause of death in people with type 2 diabetes (T2D). Due to a common underlying pathogenic mechanism, namely insulin resistance, T2D represents the main risk factor for nonalcoholic fatty liver disease (NAFLD), characterized by a buildup of fat in the liver. Globally, NAFLD is the most common liver disease, affecting a quarter of the general adult population. The development of nonalcoholic steatohepatitis (NASH) signifies an increased risk of liver fibrosis progression that can result in cirrhosis, hepatocellular carcinoma (HCC), and death. Liver fibrosis progression and development of cirrhosis is mostly asymptomatic until complications from decompensated end-stage liver disease arise. Traditionally, liver biopsy is used to diagnose NASH and stage fibrosis, however, it is invasive and costly. Non-invasive diagnostic alternatives include serum biomarkers and imaging techniques. Early identification of advanced liver fibrosis is pivotal to prompt initiation of targeted surveillance, including screening for HCC, as well as providing options for current and investigational therapeutic interventions to reduce fibrosis progression. This review gives an update on non-invasive diagnostic tools for NAFLD and liver fibrosis in the specific context of T2D, providing clinicians a pragmatic diagnostic approach to this frequent comorbidity in diabetes medicine.

TNF-Receptor-1 inhibition reduces liver steatosis, hepatocellular injury and fibrosis in NAFLD mice

Non-alcoholic fatty liver disease (NAFLD) shows an increasing prevalence and is associated with the development of liver fibrosis and cirrhosis as the major risk factors of liver-related mortality in this disease. The therapeutic possibilities are limited and restricted to life style intervention, since specific drugs for NAFLD are unavailable so far. TNFα has been implicated as a major pathogenic driver of NAFLD. TNFα-mediated liver injury occurs mainly via TNF-receptor-1 (TNFR1) signaling, whereas TNFR2 mediates protective pathways. In this study, we analyzed the therapeutic effects of a novel antibody, which selectively inhibits TNFR1 while retaining protective TNFR2 signaling in a high-fat diet (HFD) mouse model of NAFLD. Mice were fed with HFD for 32 weeks and treated with anti-TNFR1-antibody or control-antibody for the last 8 weeks. We then investigated the mechanisms of TNFR1 inhibition on liver steatosis, inflammatory liver injury, insulin resistance and fibrosis. Compared to control-antibody treatment, TNFR1 inhibition significantly reduced liver steatosis and triglyceride content, which was accompanied by reduced expression and activation of the transcription factor SREBP1 and downstream target genes of lipogenesis. Furthermore, inhibition of TNFR1 resulted in reduced activation of the MAP kinase MKK7 and its downstream target JNK, which was associated with significant improvement of insulin resistance. Apoptotic liver injury, NAFLD activity and alanine aminotransferase (ALT) levels, as well as liver fibrosis significantly decreased by anti-TNFR1 compared to control-antibody treatment. Thus, our results suggest selective TNFR1 inhibition as a promising approach for NAFLD treatment.

Predisposition to Apoptosis in Hepatocellular Carcinoma: From Mechanistic Insights to Therapeutic Strategies

Hepatocellular carcinoma (HCC) ranks among the most rapidly evolving cancers in the Western world. The majority of HCCs develop on the basis of a chronic inflammatory liver damage that predisposes liver cancer development and leads to deregulation of multiple cellular signaling pathways. The resulting dysbalance between uncontrolled proliferation and impaired predisposition to cell death with consecutive failure to clear inflammatory damage is a key driver of malignant transformation. Therefore, resistance to death signaling accompanied by metabolic changes as well as failed immunological clearance of damaged pre-neoplastic hepatocytes are considered hallmarks of hepatocarcinogenesis. Hereby, the underlying liver disease, the type of liver damage and individual predisposition to apoptosis determines the natural course of the disease as well as the therapeutic response. Here, we will review common and individual aspects of cell death pathways in hepatocarcinogenesis with a particular emphasis on regulatory networks and key molecular alterations. We will further delineate the potential of targeting cell death-related signaling as a viable therapeutic strategy to improve the outcome of HCC patients.

The efficacy of serum cell death biomarkers for diagnosing biliary tract cancer

In this study, we determined the efficacy of the cell death biomarker cytokeratin 18 for diagnosing biliary tract cancer (BTC). We recruited 36 patients with BTC (Malignant group) and 45 patients with benign biliary tract disease (Benign group) for this study. We used M30 and M65 as cell death biomarkers. M30 levels indicate apoptosis, and M65 levels indicate both apoptosis and necrosis. M30 and M65 levels were significantly higher in the Malignant group than in the Benign group (142.4 ± 117.0 vs 48.9 ± 71.2 U/l, P < 0.001; 1513.3 ± 837.4 vs 882.2 ± 831.2 U/l, P = 0.001). The diagnosability of M30 was the highest of the four markers (CEA, CA19-9, M30, M65) (cut-off value: 74.429 U/l, sensitivity: 72.2%, specificity: 77.1%, AUC: 0.771). The sensitivity of M30 (cut-off value: 74.429 U/l) was significantly higher than that of biliary cytology (76% (19/25) vs 12% (3/25), P < 0.001), and the accuracy of M30 was significantly higher than that of biliary cytology (78.3% (36/46) vs 52.2% (24/46), P = 0.015). The sensitivity of M30 (cut-off value: 74.429 U/l) was significantly higher than that of biliary cytology and brush cytology (72.4% (21/29) vs 24.1% (7/29), P < 0.001). In conclusion, cell death biomarkers were increased in patients with BTC, and M30 could efficiently diagnose BTC.