Monitoring SCCA-IgM complexes in serum predicts liver disease progression in patients with chronic hepatitis

The protease activated receptor 2 - CCAAT/enhancer-binding protein beta - SerpinB3 axis inhibition as a novel strategy for the treatment of non-alcoholic steatohepatitis

OBJECTIVE

The serine protease inhibitor SerpinB3 has been described as critical mediator of liver fibrosis and it has been recently proposed as an additional hepatokine involved in NASH development and insulin resistance. Protease Activated Receptor 2 has been identified as a novel regulator of hepatic metabolism. A targeted therapeutic strategy for NASH has been investigated, using 1-Piperidine Propionic Acid (1-PPA), since this compound has been recently proposed as both Protease Activated Receptor 2 and SerpinB3 inhibitor.

METHODS

The effect of SerpinB3 on inflammation and fibrosis genes was assessed in human macrophage and stellate cell lines. Transgenic mice, either overexpressing SerpinB3 or carrying Serpinb3 deletion and their relative wild type strains, were used in experimental NASH models. Subgroups of SerpinB3 transgenic mice and their controls were also injected with 1-PPA to assess the efficacy of this compound in NASH inhibition.

RESULTS

1-PPA did not present significant cell and organ toxicity and was able to inhibit SerpinB3 and PAR2 in a dose-dependent manner. This effect was associated to a parallel reduction of the synthesis of the molecules induced by endogenous SerpinB3 or by its paracrine effects both in vitro and in vivo, leading to inhibition of lipid accumulation, inflammation and fibrosis in experimental NASH. At mechanistic level, the antiprotease activity of SerpinB3 was found essential for PAR2 activation, determining upregulation of the CCAAT Enhancer Binding Protein beta (C/EBP-β), another pivotal regulator of metabolism, inflammation and fibrosis, which in turn determined SerpinB3 synthesis.

CONCLUSIONS

1-PPA treatment was able to inhibit the PAR2 - C/EBP-β - SerpinB3 axis and to protect from NASH development and progression, supporting the potential use of a similar approach for a targeted therapy of NASH.

The polymorphic variant of SerpinB3 (SerpinB3-PD) is associated with faster cirrhosis decompensation

BACKGROUND

SerpinB3 is a cysteine protease inhibitor involved in liver disease progression due to its proinflammatory and profibrogenic properties. The polymorphic variant SerpinB3-PD (SB3-PD), presents a substitution in its reactive centre loop, determining the gain of function.

AIMS

To disclose the clinical characteristics of a cohort of patients with cirrhosis in relation to the presence of SB3-PD and to assess the effect of this genetic variant on fibrogenic and inflammatory cytokines in vitro.

METHODS

We assessed SB3 polymorphism in 90 patients with cirrhosis, prospectively followed up in our referral centre. We used HepG2 and HuH-7 cells transfected to overexpress either wild-type SB3 (SB3-WT) or SB3-PD to assess their endogenous effect, while LX2 and THP-1 cells were treated with exogenous SB3-WT or SB3-PD proteins.

RESULTS

Patients carrying SB3-PD had more severe portal hypertension and higher MELD scores, than patients carrying SB3-WT. In multivariate analysis, SB3-PD was an independent predictor of cirrhosis complications. Patients with SB3-PD polymorphism presented with more severe liver fibrosis and inflammatory features. Hepatoma cells overexpressing SB3-PD showed higher TGF-β1 expression than controls. The addition of recombinant SB3-PD induced an up-regulation of TGF-β1 in LX2 cells and a more prominent inflammatory profile in THP-1 cells, compared to the effect of SB3-WT protein.

CONCLUSIONS

The polymorphic variant SB3-PD is highly effective in determining activation of TGF-β1 and inflammation in vitro. Patients with cirrhosis who carry SB3-PD polymorphism may be more prone to develop severe liver disease progression. However, further validation studies are warranted to support the in vivo relevance of this polymorphism.

SerpinB3 as a Pro-Inflammatory Mediator in the Progression of Experimental Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is becoming the most common chronic liver disease worldwide. In 20-30% of patients, NAFLD can progress into non-alcoholic steatohepatitis (NASH), eventually leading to fibrosis, cirrhosis and hepatocellular carcinoma development. SerpinB3 (SB3), a hypoxia-inducible factor-2α dependent cysteine protease inhibitor, is up-regulated in hepatocytes during progressive NAFLD and proposed to contribute to disease progression. In this study we investigated the pro-inflammatory role of SB3 by employing phorbol-myristate acetate-differentiated human THP-1 macrophages exposed in vitro to human recombinant SB3 (hrSB3) along with mice overexpressing SB3 in hepatocytes (TG/SB3) or knockout for SB3 (KO/SB3) in which NASH was induced by feeding methionine/choline deficient (MCD) or a choline-deficient, L-amino acid defined (CDAA) diets. In vivo experiments showed that the induction of NASH in TG/SB3 mice was characterized by an impressive increase of liver infiltrating macrophages that formed crown-like aggregates and by an up-regulation of hepatic transcript levels of pro-inflammatory cytokines. All these parameters and the extent of liver damage were significantly blunted in KO/SB3 mice. In vitro experiments confirmed that hrSB3 stimulated macrophage production of M1-cytokines such as TNFα and IL-1β and reactive oxygen species along with that of TGFβ and VEGF through the activation of the NF-kB transcription factor. The opposite changes in liver macrophage activation observed in TG/SB3 or KO/SB3 mice with NASH were associated with a parallel modulation in the expression of triggering receptor expressed on myeloid cells-2 (TREM2), CD9 and galectin-3 markers, recently detected in NASH-associated macrophages. From these results we propose that SB3, produced by activated/injured hepatocytes, may operate as a pro-inflammatory mediator in NASH contributing to the disease progression.

Immunodiagnostic Biomarkers for Hepatocellular Carcinoma (HCC): The First Step in Detection and Treatment

Hepatocellular carcinoma (HCC) exerts huge effects on the health burden of the world because of its high mortality and poor prognosis. HCC is often clinically detected late in patients. If HCC could be detected and treated earlier, the survival rate of patients will be greatly improved. Therefore, identifying specific biomarkers is urgent and important for HCC. The liver is also recognized as an immune organ. The occurrence of HCC is related to exacerbation of immune tolerance and/or immunosurveillance escape. The host immune system plays an important role in the recognition and targeting of tumor cells in cancer immunotherapy, as can be seen from the clinical success of immune checkpoint inhibitors and chimeric antigen receptor (CAR) T cells. Thus, there is a pressing medical need to discover immunodiagnostic biomarkers specific to HCC for understanding the pathological mechanisms of HCC, especially for immunotherapy targets. We have reviewed the existing literature to summarize the immunodiagnostic markers of HCC, including autoantibodies against tumor-associated antigens (TAAs) and exosomes, to provide new insights into HCC and early detection of this deadly cancer.

Squamous cell carcinoma antigen-IgM (SCCA-IgM) is associated with interstitial lung disease in systemic sclerosis

OBJECTIVE

Interstitial lung disease (ILD) is the major determinant of prognosis in patients with systemic sclerosis (SSc). Squamous Cell Carcinoma Antigen (SCCA1) is a serin protease inhibitor which plays a pivotal role in inflammation and fibrosis. SCCA1 is overexpressed in pulmonary tissue of patients with idiopathic pulmonary fibrosis and can be detectable in serum as circulating immune complex bound to IgM (SCCA-IgM). We aimed to investigate the association between SCCA-IgM and clinical features of patients with SSc.

METHODS

Ninety-seven patients with SSc (ACR/EULAR criteria) were consecutively enrolled in the study. Clinical and serological variables and organ involvement were recorded. Pulmonary involvement was investigated by high-resolution CT (HRCT) and respiratory function tests. SCCA-IgM serum levels were measured by a validated ELISA assay (Hepa-IC, Xeptagen, Venice, Italy). We set the cut-off value for serum levels of SCCA-IgM >200 AU/ml, calculated as mean+3 standard deviations in 100 healthy subjects.

RESULTS

Forty-one (42.3%) patients were affected with ILD. SCCA-IgM values were significantly higher in patients with ILD than in those without: 218 (80-402) vs. 87.5 (59-150) AU/mL, P=0.003. Patients with positive SCCA-IgM had more frequently ILD (69.7% vs. 28.1%, P≤0.0001) and a lower total lung capacity (TLC) (P=0.024) compared with negative ones. No differences were found in any other clinical and serological features. At multivariate analysis, SCCA-IgM was found to be associated with ILD diagnosis (OR 10.6, IC 2.9-38.4, P=0.001).

CONCLUSION

SCCA-IgM is associated with interstitial lung disease in scleroderma patients and might be used in the assessment of SSc-ILD.

Squamous cell carcinoma antigen 1 is associated to poor prognosis in esophageal cancer through immune surveillance impairment and reduced chemosensitivity

Squamous cell carcinoma antigen‐1 (SCCA1) overexpression is associated with poor prognosis and chemoresistance in several tumor types, however, the underlying mechanisms remain elusive. Here, we report SCCA1 in relation to the immune and peritumoral adipose tissue microenvironment in early and advanced esophageal adenocarcinoma (EAC). In our series of patients with EAC, free SCCA1 serum levels were associated with significantly worse overall survival, and SCCA1‐IgM serum levels showed a trend to a worse overall survival. Serum SCCA1 and intratumoral SCCA1 were inversely correlated with immune activation markers. In agreement with these findings, SCCA1 induced the expression of the immune checkpoint molecule programmed death ligand‐1 on monocytes and a direct correlation of these 2 molecules was observed in sequential tumor sections. Furthermore, SCCA1 mRNA expression within the tumor was inversely correlated with stem cell marker expression both within the tumor and in the peritumoral adipose tissue. In vitro, in EAC cell lines treated with different chemotherapeutic drugs, cell viability was significantly modified by SCCA1 presence, as cells overexpressing SCCA1 were significantly more resistant to cell death. In conclusion, poor prognosis in EAC overexpressing SCCA1 is due to reduced tumor chemosensitivity as well as intratumoral immunity impairment, likely induced by this molecule.

SCCA-IgM as a Potential Biomarker of Non-Alcoholic Fatty Liver Disease in Patients with Obesity, Prediabetes and Diabetes Undergoing Sleeve Gastrectomy

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) has a high prevalence in obesity and its presence should be screened. Laparoscopic sleeve gastrectomy (LSG) is an effective treatment for obesity, but its effects on NAFLD are still to be firmly established. The diagnosis of non-alcoholic steatohepatitis (NASH) is currently performed by liver biopsy, a costly and invasive procedure. Squamous cell carcinoma antigen-IgM (SCCA-IgM) is a biomarker of viral hepatitis to hepatocellular carcinoma development and its role in NAFLD to NASH progression has not yet been investigated.

OBJECTIVE

The aim of this study was to evaluate SCCA-IgM as a non-invasive biomarker of NAFLD/NASH in patients with different degrees of metabolic-complicated obesity before and after LSG.

METHOD

Fifty-six patients with obesity were studied before and 12 months after LSG; anthropometric, biochemical, clinical, and imaging data were collected.

RESULTS

At baseline steatosis was strongly associated with the glycaemic profile (p = 0.016) and was already present in prediabetic patients with obesity (82%). Only 3 patients had an SCCA-IgM level above the normal cut-off. SCCA-IgM titre did not change according to glycaemic profile or steatosis. Metabolic and inflammatory factors and transaminases significantly reduced after LSG-induced weight loss, except for SCCA-IgM. The ALT/AST ratio decreased post-LSG correlated with BMI (r = 0.297, p = 0.031), insulin (r = 0.354, p = 0.014), and triglycerides (r = 0.355, p = 0.009) reduction.

CONCLUSIONS

Our results confirm the tight link between NAFLD and metabolic complications, suggesting prediabetes as a new risk factor of steatosis. SCCA-IgM does not seem to have a role in the identification and prognosis of NAFLD.

Diagnostic accuracy of SCCA and SCCA-IgM for hepatocellular carcinoma: A meta-analysis

BACKGROUND & AIMS

Squamous cell carcinoma antigen (SCCA) and its immune complex (SCCA-IgM) have been proposed for use in the screening of hepatocellular carcinoma (HCC). We conducted a meta-analysis to evaluate the diagnostic performance of SCCA and SCCA-IgM and of both combined with alpha-foetoprotein.

METHODS

After a systematic review of the relevant studies, the sensitivity, specificity, positive and negative likelihood ratios, diagnostic odds ratio (DOR) and area under curve (AUC) for the diagnosis of HCC were pooled using bivariate meta-analysis. Hierarchic summary receiver operating characteristic curves were used to summarize the overall test performance. Bivariate boxplots were used to confirm whether the threshold effect existed. A Fagan nomogram was used to assess the clinical utility. Heterogeneity was explored by sensitivity analysis, univariable meta-regression and subgroup analysis.

RESULTS

Eleven studies that had HCC diagnosis as their purpose were ultimately included in the quantitative analysis. The summary estimates were as follows: SCCA (AUC: 0.80 [95% CI: 0.76-0.83]) and SCCA-IgM (AUC: 0.77 [95% CI: 0.74-0.83]) demonstrated similar diagnostic performance, while a combination of AFP and SCCA-IgM had an AUC of 0.90 (95% CI: 0.87-0.92) and a DOR of 22.87 (95% CI: 8.38-62.40). Meta-regression showed that patient selection, cut-off values, reference standards and tumour biopsy as the diagnostic method significantly influenced the heterogeneity of the included studies.

CONCLUSIONS

Both SCCA and SCCA-IgM showed a moderate diagnostic accuracy for HCC screening; the combination of SCCA-IgM and AFP is the best diagnostic option.

Hypoxia-inducible factor 2α drives nonalcoholic fatty liver progression by triggering hepatocyte release of histidine-rich glycoprotein

Mechanisms underlying progression of nonalcoholic fatty liver disease (NAFLD) are still incompletely characterized. Hypoxia and hypoxia-inducible factors (HIFs) have been implicated in the pathogenesis of chronic liver diseases, but the actual role of HIF-2α in the evolution of NAFLD has never been investigated in detail. In this study, we show that HIF-2α is selectively overexpressed in the cytosol and the nuclei of hepatocytes in a very high percentage (>90%) of liver biopsies from a cohort of NAFLD patients at different stages of the disease evolution. Similar features were also observed in mice with steatohepatitis induced by feeding a methionine/choline-deficient diet. Experiments performed in mice carrying hepatocyte-specific deletion of HIF-2α and related control littermates fed either a choline-deficient L-amino acid-defined or a methionine/choline-deficient diet showed that HIF-2α deletion ameliorated the evolution of NAFLD by decreasing parenchymal injury, fatty liver, lobular inflammation, and the development of liver fibrosis. The improvement in NAFLD progression in HIF-2α-deficient mice was related to a selective down-regulation in the hepatocyte production of histidine-rich glycoprotein (HRGP), recently proposed to sustain macrophage M1 polarization. In vitro experiments confirmed that the up-regulation of hepatocyte HRGP expression was hypoxia-dependent and HIF-2α-dependent. Finally, analyses performed on specimens from NAFLD patients indicated that HRGP was overexpressed in all patients showing hepatocyte nuclear staining for HIF-2α and revealed a significant positive correlation between HIF-2α and HRGP liver transcript levels in these patients.

CONCLUSIONS

These results indicate that hepatocyte HIF-2α activation is a key feature in both human and experimental NAFLD and significantly contributes to the disease progression through the up-regulation of HRGP production. (Hepatology 2018;67:2196-2214).

Biomarkers development for early detection of cancer: Reducing the burden of cancer in the ageing society

The ageing process in the European society will become one of the key driving forces of change over the next decades. The specific demands of older generations constitute a key market of the future, and the pressure to improve and expand health services increases, especially as far as chronic diseases, such as cancer. Availability of cost effective cancer early detection protocols, based on predictive biomarkers, will improve patients management reducing consequently the high costs associated to treating patients when the disease is at an advanced stage.

Characterization of SCCA-IgM as a biomarker of liver disease in an Asian cohort of patients

Viral hepatitis infection is a major global issue and a leading cause of liver disease and associated deaths. Over time, patients infected with hepatitis B (HBV) or C virus (HCV) develop cirrhosis and, eventually, hepatocellular carcinoma (HCC). For this reason, they need to be constantly monitored. Current Asian guidelines recommend the determination of serum alpha-fetoprotein (AFP) together with liver ultrasounds every six months to detect HCC nodules. However, both methods have several limitations, and other biomarkers have been studied for monitoring cirrhosis, including SCCA-IgM, an immune-complex formed by Squamous Cell Carcinoma Antigen and IgM. To date, SCCA-IgM has been validated as a novel biomarker for liver diseases only in European populations. The aim of our study was to analyze SCCA-IgM as a biomarker to monitor cirrhosis evolution in an Asian cohort of patients and to compare its performance to that of AFP. We analyzed the concentration of AFP and SCCA-IgM in serum samples obtained from a group of Asian adult patients with cirrhosis or HCC and a control group of patients admitted for gastrointestinal disorders. In untreated patients and similarly to AFP, SCCA-IgM levels were significantly higher in patients with cirrhosis compared to those with HCC. In addition, SCCA-IgM, but not AFP serological levels, were significantly lower in HCC patients who were treated with surgical resection compared to those who received a different therapy.

Circulating SCCA-IgM complex is a useful biomarker to predict the outcome of therapy in hepatocellular carcinoma patients

INTRODUCTION

Hepatocellular carcinoma (HCC) develops in about 3-4% of cirrhotic patients every year. The squamous cell carcinoma antigen (SCCA) has been found elevated in liver cancer specimens by immunohistochemistry, and detected in complex with IgM (SCCA-IgM) in the serum of patients with HCC. The aim of this study was to evaluate the ability of serological SCCA-IgM levels to predict the efficacy of HCC therapy.

MATERIALS AND METHODS

From April 2012 to April 2014, 131 patients with a new diagnosis of HCC were enrolled. The HCC diagnosis was made according to the EASL guidelines. The patients were staged and treated according to the BCLC Staging System: BCLC stages A and B were treated with locoregional therapy, and BCLC stage C was treated with Sorafenib. Response to therapy was evaluated according to the mRECIST criteria. Serum SCCA-IgM levels were determined by a commercially available ELISA kit at basal time (T₀) and after one month of treatment (T₁).

RESULTS

At baseline and one month into therapy, SCCA-IgM levels were significantly lower (p value <.05) in patients who responded to therapy compared to those who did not respond (median SCCA-IgM level [25th + 75th percentile] at T₀:115.1 AU/mL [50.0 + 174.4] vs. 149.1 AU/mL [111.3 + 198.8]; median SCCA-IgM level [25th + 75th percentile] at T₁: 113.4 AU/mL [50.0 + 194.2] vs. 170.6 AU/mL [111.7 + 344.2]).

CONCLUSION

Our study suggests that the SCCA-IgM determination could be helpful in predicting the response to therapy in patients with HCC.

SerpinB3 Promotes Pro-fibrogenic Responses in Activated Hepatic Stellate Cells

SerpinB3 is a hypoxia- and hypoxia-inducible factor-2α-dependent cystein protease inhibitor that is up-regulated in hepatocellular carcinoma and in parenchymal cells during chronic liver diseases (CLD). SerpinB3 up-regulation in CLD patients has been reported to correlate with the extent of liver fibrosis and the production of transforming growth factor-β1, but the actual role of SerpinB3 in hepatic fibrogenesis is still poorly characterized. In the present study we analyzed the pro-fibrogenic action of SerpinB3 in cell cultures and in two different murine models of liver fibrosis. "In vitro" experiments revealed that SerpinB3 addition to either primary cultures of human activated myofibroblast-like hepatic stellate cells (HSC/MFs) or human stellate cell line (LX2 cells) strongly up-regulated the expression of genes involved in fibrogenesis and promoted oriented migration, but not cell proliferation. Chronic liver injury by CCl4 administration or by feeding a methionine/choline deficient diet to transgenic mice over-expressing human SerpinB3 in hepatocytes confirmed that SerpinB3 over-expression significantly increased the mRNA levels of pro-fibrogenic genes, collagen deposition and αSMA-positive HSC/MFs as compared to wild-type mice, without affecting parenchymal damage. The present study provides for the first time evidence that hepatocyte release of SerpinB3 during CLD can contribute to liver fibrogenesis by acting on HSC/MFs.

Squamous cell carcinoma antigen-IgM is associated with hepatocellular carcinoma in patients with cirrhosis: A prospective study

BACKGROUND

Squamous cell carcinoma antigen (SCCA)-IgM complex has been described as a promising tool to identify patients with progressive liver disease at higher risk of hepatocellular carcinoma (HCC) development in retrospective studies.

AIM

To assess the clinical value of this biomarker in patients with cirrhosis in a prospective study.

METHODS

Patients with overt cirrhosis were prospectively evaluated at 6-month intervals for HCC development and decompensation with clinical examination, liver ultrasound, α-fetoprotein measurement. SCCA-IgM was measured in serum by immunoenzymatic assay. Median follow-up duration was 52 months (range 12-68 months).

RESULTS

70 patients (26% male; mean age 56±10 years) were enrolled. The main aetiological factors were alcohol (44%) and hepatitis C (34%). Baseline values of SCCA-IgM were significantly higher in patients who developed HCC. Positivity of the biomarker at baseline was associated with a significantly shorter HCC-free survival, while α-fetoprotein (cut off >20 ng/ml) was not significant. SCCA-IgM positivity and hepatitis C were significant prognostic factors for HCC development. The biomarker was not associated with the development of clinical complications of cirrhosis.

CONCLUSION

This prospective study demonstrates that in patients with cirrhosis SCCA-IgM is associated with HCC development and may be useful for clinical management of cirrhotic patients at higher risk of HCC development.

Clinical applications of squamous cell carcinoma antigen-immunoglobulins M to monitor chronic hepatitis C

Hepatitis C virus (HCV) is the main cause of chronic liver disease and cirrhosis in Western countries. Over time, the majority of cirrhotic patients develop hepatocellular carcinoma (HCC), one of the most common fatal cancers worldwide - fourth for incidence rate. A high public health priority need is the development of biomarkers to screen for liver disease progression and for early diagnosis of HCC development, particularly in the high risk population represented by HCV-positive patients with cirrhosis. Several studies have shown that serological determination of a novel biomarker, squamous cell carcinoma antigen-immunoglobulins M (SCCA-IgM), might be useful to identify patients with progressive liver disease. In the initial part of this review we summarize the main clinical studies that have investigated this new circulating biomarker on HCV-infected patients, providing evidence that in chronic hepatitis C SCCA-IgM may be used to monitor progression of liver disease, and also to assess the virological response to antiviral treatment. In the last part of this review we address other, not less important, clinical applications of this biomarker in hepatology.

New biomarkers for clinical management of hepatitis C virus infected patients

Hepatocellular carcinoma (HCC) is the third most frequent oncological cause of death worldwide, principally a consequence of hepatitis C virus (HCV) infection and its prognosis is mostly poor. For early identification and surveillance of HCV patients with liver disease progression, the availability of suitable diagnostic and prognostic biomarkers is still an unmet clinical need. Alfa-fetoprotein together with imaging techniques is commonly used, however its specificity and sensitivity are not satisfactory. Several clinical and serological data have been proposed to define the risk of disease progression in HCV infected patients and new biomarkers have been proposed, including post-transcriptionally modified molecules and genetic biomarkers. The present editorial article attempts to summarize the current knowledge on the new promising tools for effective early diagnosis of HCV-related liver disease progression and for the surveillance of HCC.

HCV genotype 3 and squamous cell carcinoma antigen (SCCA)-IgM are independently associated with histological features of NASH in HCV-infected patients

Nonalcoholic steatohepatitis (NASH) enhances the risk of progressive liver disease. In chronic hepatitis C (CHC), liver steatosis is frequent, especially in genotype 3, but its clinical significance is debated. As squamous cell carcinoma antigen (SCCA)-IgM has been associated with advanced liver disease and risk of tumour development, we evaluated its occurrence in CHC and the possible relation with NASH at liver biopsy. Using a validated ELISA, serum SCCA-IgM was measured in 91 patients with CHC at the time of liver biopsy performed before antiviral treatment, at the end of treatment and 6 months thereafter, and in 93 HCV-negative patients with histological diagnosis of nonalcoholic fatty liver disease, as controls. SCCA-IgM was detected in 33% of CHC patients and in 4% of controls. This biomarker was found more elevated in CHC patients with histological NASH, and at multivariate analysis, SCCA-IgM and HCV genotype 3 were independently associated with NASH [OR (95% CI): 6.94 (1.21-40) and 27.02 (4.44-166.6)]. As predictors of NASH, HCV genotype 3 and SCCA-IgM had a specificity and a sensitivity of 97% and 44%, and of 95% and 27%, respectively. PPV and NPV were 80% and 86% for HCV genotype 3 vs 73% and 72% for SCCA-IgM. In patients with sustained virologic response to therapy, SCCA-IgM levels decreased significantly, while these remained unchanged in nonresponders. In conclusion, SCCA-IgM is detectable in one-third of patients with CHC and significantly correlates with histological NASH.

Detection of high levels of Survivin-immunoglobulin M immune complex in sera from hepatitis C virus infected patients with cirrhosis

AIM

The identification and surveillance of patients with liver dysfunctions and the discovering of new disease biomarkers are needed in the clinical practice. The aim of this study was to investigate on Survivin-immunoglobulin (Ig)M immune complex (IC) as a potential biomarker of chronic liver diseases.

METHODS

Serum levels of Survivin-IgM were measured using an enzyme-linked immunoassay that had been standardized and validated in our laboratory in 262 individuals, including healthy subjects and patients with chronic viral hepatitis, cirrhosis and hepatocellular carcinoma (HCC).

RESULTS

Survivin-IgM IC was lower in healthy subjects (median, 99.39 AU/mL) than in patients with chronic viral hepatitis (median, 148.03 AU/mL; P = 0.002) or with cirrhosis (median, 371.00 AU/mL; P < 0.001). Among patients with cirrhosis, those with hepatitis C virus (HCV) infection showed the highest level of Survivin-IgM IC (median, 633.71 AU/mL; P < 0.001). The receiver-operator curve analysis revealed that Survivin-IgM accurately distinguishes HCV correlated cirrhosis from chronic viral hepatitis (area under the curve [AUC], 0.738; sensitivity, 74.5%; specificity, 70.7%). A multivariate logistic regression model, including Survivin-IgM IC, aspartate aminotransferase (AST) and AST/alanine aminotransferase (ALT) ratio increased the prediction accuracy for the identification of the cirrhotic HCV patients (AUC, 0.818; sensitivity, 87.2%; specificity, 65.9%). Conversely, Survivin-IgM IC significantly decreased in HCC patients (median, 165.72 AU/mL; P = 0.022).

CONCLUSION

Our results suggest that Survivin-IgM immune complex may be used as a potential biomarker for liver damage, particularly for the identification of the HCV-related cirrhotic population.

Diagnostic and prognostic role of SCCA-IgM serum levels in hepatocellular carcinoma (HCC)

BACKGROUND AND AIM

The serpin squamous cell carcinoma antigen complexed with IgM (SCCA-IgM) has been reported as a promising serological marker for hepatocellular carcinoma (HCC). We aimed to further evaluate SCCA-IgM diagnostic accuracy and to determine its prognostic role.

METHODS

SCCA-IgM levels were determined in 327 sera obtained from 81 HCC patients, 206 cirrhotics and 40 healthy blood donors (controls). Sensitivity, specificity, correlation with clinical and tumor parameters and with survival were evaluated.

RESULTS

HCC patients had SCCA-IgM levels significantly higher than controls and cirrhotics (P < 0.0001). Sensitivity, specificity, positive and negative predictive values for HCC were 89%, 50%, 41% and 92%, respectively. In comparison, sensitivity and specificity for alphafetoprotein were 48% and 85%. SCCA-IgM levels were not significantly correlated with clinical or biological variables. With a cut-off of 130 AU/mL (receiver operating characteristic curves), SCCA-IgM proved efficient in the prediction of prognosis, identifying the patients with long overall survival (efficiency validated in the homogenous subgroup of patients with intermediate-stage HCC undergoing transarterial chemoembolization) and predicting progression-free survival. A Cox multivariate analysis confirmed SCCA-IgM predictive value, identifying tumor size and SCCA-IgM levels as independent predictors of survival. A reduction in SCCA-IgM levels correlated with response to treatment.

CONCLUSIONS

SCCA-IgM is a sensitive marker of HCC in patients with cirrhosis even though lacking in specificity. The determination of the levels of the marker in HCC patients is highly efficient in predicting the patients' prognosis, identifying those with long overall and progression-free survival and the responders and should be introduced in the clinical practice.

Hepatocellualar carcinoma serum markers

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in some areas of the world. In most cases, HCC is diagnosed at a late stage. Therefore, the prognosis of patients with HCC is generally poor. The recommended screening strategy for patients with cirrhosis includes the determination of serum α-fetoprotein (AFP) levels and an abdominal ultrasound every 6 months to detect HCC at an earlier stage. AFP, however, is a marker characterized by poor sensitivity and specificity, and abdominal ultrasound is highly dependent on the operator's experience. In addition to AFP, Lens culinaris agglutinin-reactive AFP (AFP-L3), des-γ-carboxy prothrombin (DCP), glypican-3 (GPC-3), osteopontin (OPN), and several other biomarkers (such as squamous cell carcinoma antigen-immunoglobulin M complexes [SCCA-IgM], alpha-1-fucosidase [AFU], chromogranin A [CgA], human hepatocyte growth factor, insulin-like growth factor) have been proposed as markers for the early detection of HCC. For these markers, we describe the mechanisms of production, and their diagnostic and prognosis roles. None of them is optimal; however, when used together, their sensitivity in detecting HCC is increased. Recent research has shown that some biomarkers have mitogenic and migratory activities in the angiogenesis of HCC and are a factor of tumor growth.

IgM-linked SerpinB3 and SerpinB4 in sera of patients with chronic liver disease

Background

Epidemiological studies indicate that a growing number of cirrhotic patients will develop hepatocellular carcinoma (HCC) in the next decade. Recent findings have demonstrated that Squamous cell carcinoma antigen 1 (SCCA1) and 2 (SCCA2) isoforms, now classified as serpinB3 and serpinB4, are over-expressed in HCC, but not in normal liver. As reported, high levels of circulating SCCA-IgM immunocomplexes in patients with cirrhosis are significantly associated with HCC development.

Aim

To ascertain whether IgM-linked SCCA isoforms circulate in patients with chronic liver disease, compared to total SCCA-IgM levels.

Methodology and Findings

79 patients with chronic liver disease were studied, including 17 patients with chronic hepatitis, 36 patients with cirrhosis and 26 with HCC. 28 blood donors were used as control. Monoclonal antibodies against serpinB3 and serpinB4 were used as catcher antibodies to set up specific ELISA assays, while total SCCA-IgM immunocomplexes were detected by commercially available ELISA assay. Overall, the results revealed a better diagnostic sensitivity of total SCCA-IgM assay, compared to both serpinB3 and serpinB4 IgM-linked assays. SerpinB4-IgM median values obtained with SCC103 antibody were moderately higher in patients with cirrhosis than in those with HCC, median values: 0.168 (IQR 0.140–0.427) vs. 0.140 (IQR 0.140–0.278), (p = 0.177). A trend toward decreasing serpinB4-IgM/serpinB3-IgM median ratio was observed in patients with advanced liver disease, being 1.08 in patients with HCC, 1.10 in patients with cirrhosis and 1.40 in patients with chronic hepatitis (p = 0.079).

Conclusions

IgM-linked SCCA isoforms in serum of patients with chronic liver diseases were quantified for the first time. Although the number of patients was limited, this preliminary study reveals that the relative balance of the two serpin isoforms is altered in HCC and it is characterized by a lower serpinB4-IgM/serpinB3-IgM ratio, determined by lower serpinB4 levels.

Increased plasma concentrations of tumour markers in the absence of neoplasia

Tumour markers are a very heterogeneous group of molecules that are generally found in very small concentrations in the plasma and serum of healthy individuals. In the process of neoplastic differentiation the cell can synthesize, release, or induce synthesis of other cells, thus increasing their concentration in plasma and serum. These substances may also increase their plasma concentration in patients without cancer due to processes that increase the release or reduce catabolism, and so give rise to false positives. An understanding of the main physiopathological processes that increase the concentrations of these substances could improve our interpretation of tumour markers and their clinical application. In this study we review the physiopathological processes that may increase the plasma concentrations of tumour markers. We performed a bibliography review in PubMed, searching for causes of false positives for the following tumour markers: α-Fetoprotein, CA 125, CA 15-3, CA 19-9, CA 72-4, carcinoembryonic antigen, CYFRA 21-1, squamous cell carcinoma, prostatic specific antigen, β(2)-microglobulin, choriogonadotropin (β chain), chromogranin A, neuron specific enolase, HER2-neu, progastrin releasing peptide, S-100, and thyroglobulin. The results favour the use of tests which can identify pathological processes that may increase tumour marker concentrations.

Combinatorial Semisynthesis of Biomarker-IgM Complexes

Circulating immune complexes formed by tumor antigens and immunoglobulin M (IgM) represent a novel class of biomarkers with diagnostic value for early cancer detection. The quantitative analysis of these immune complexes is achieved by enzyme-linked immunosorbent assay (ELISA) methods using a purified calibrator from samples of patients with cancer. These complexes obtained from samples of human origin are not suitable for cost-effective production processes with high safety standards. Given the ill-defined biomarker/IgM ratio in these complexes, semisynthesis with retention of functional properties is difficult to achieve and may vary widely according to the batch-to-batch heterogeneity of starting biological preparations. Here the authors describe the development of a combinatorial method for defining the optimal reaction conditions for the reproducible semisynthesis of biomarker-IgM complexes by exploiting the biotin-avidin technology. The method relies on screening by ELISA the 3D composition space defined by the combinatorial variation of biotinylated-biomarker, biotinylated-IgM, and avidin concentrations aiming to select those conditions leading to biomarker-IgM complexes with the highest immunoreactivity. The method allows the reproducible synthesis of species with immunoreactivity comparable to that of natural immune complexes and endowed with sufficient stability to be used as calibrators in ELISA.

Successful antiviral therapy determines a significant decrease in squamous cell carcinoma antigen-associated (SCCA) variants' serum levels in anti-HCV positive cirrhotic patients

Aberrant squamous cell carcinoma antigen (SCCA) expression is an early event in hepatocarcinogenesis, and increasing serum levels of SCCA variants IgM immune complexes (SCCA-IgM IC) have been found in cirrhotic patients developing hepatocellular carcinoma (HCC). We longitudinally evaluated a cohort of cirrhotic patients with hepatitis C virus infection (HCV) who underwent pegylated interferon (PEG-IFN) and ribavirin treatment. SCCA-IgM IC levels were assessed in the sera of 33 cirrhotic patients with HCV (21 males, median age 57 years) before, at the end and at 6-month and 1-year follow-up after treatment with PEG-IFN and ribavirin. SCCA-IgM IC serum levels (arbitrary units/mL, AU/mL) were evaluated according to treatment outcome: sustained virological response (SVR) vs nonresponse (NR). Overall, 15 patients obtained a SVR to antiviral therapy (45%). There was no significant difference in baseline SCCA-IgM IC serum levels between SVR and NR patients. When compared to baseline (451.2 AU/mL), SVR patients showed a significant decrease in median SCCA-IgM IC serum levels at the end of treatment (186.8 AU/mL, P = 0.013) and at both 6-month (96.8 AU/mL, P < 0.001) and 1-year follow-up (52.4 AU/mL, P < 0.001), while no significant modification was observed in NR patients. In patients with HCV-related liver cirrhosis, successful antiviral therapy is associated with a dramatic and significant decrease in SCCA-IC serum levels. Because of the pathophysiological correlation between SCCA and liver carcinogenesis, it is hypothesized that in patients with liver cirrhosis, SVR may be accompanied by a decreased proliferative stimulation.

SERPINB3 modulates TGF-beta expression in chronic liver disease

Transforming growth factor-beta1 (TGF-beta1) is the master cytokine in the pathogenesis of liver fibrosis. TGF-beta1 and extent of fibrosis were correlated recently to the serpin SERPINB3 in idiopathic pulmonary fibrosis, a chronic disease recalling liver cirrhosis. The aim of this study was to assess the relation between SERPINB3, TGF-beta1 and fibrosis in chronic liver diseases and to determine the effect of this serpin on TGF-beta1 expression using in vitro models. SERPINB3 and TGF-beta1 were evaluated in liver biopsies of 94 patients with chronic liver disease. The effect of SERPINB3 on TGF-beta1 expression was determined in primary human hepatocytes, HepG2 and Huh7 cells transfected with intact SERPINB3 human gene or with reactive site loop deleted mutants. A significant correlation between TGF-beta1 and SERPINB3 at the protein level was observed in liver biopsies, confirmed by a positive correlation at mRNA level. Both proteins were correlated to the extent of liver fibrosis. All transfected cells showed increased TGF-beta1 mRNA and protein production and the integrity of the reactive site loop of the serpin was crucial to achieve this effect. In conclusion, chronically damaged hepatocytes produce SERPINB3 and TGF-beta, and the anti-protease activity of this serpin might be implicated in TGF-beta1 induction.