Early recognition of hepatocellular carcinoma based on altered profiles of alpha-fetoprotein

Utility of Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein and des-gamma-carboxy prothrombin, alone or in combination, as biomarkers for hepatocellular carcinoma

BACKGROUND & AIMS

Des-gamma-carboxy prothrombin (DCP) and Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3) are surveillance markers used to detect hepatocellular carcinoma (HCC) in Japan. This study evaluated their utility, alone or in combination, in a North American population.

METHODS

Patients with hepatitis C virus-related cirrhosis were followed up prospectively for 2 years.

RESULTS

Of 372 patients, HCC developed in 34 of 298 who were free of HCC at entry. The overall sensitivity, specificity, and positive and negative predictive values for only AFP (>20 ng/mL) were 61%, 71%, 34%, and 88%, respectively; for only AFP-L3% (>10) were 37%, 92%, 52%, and 85%, respectively; and for only DCP (>7.5 ng/mL) were 39%, 90%, 48%, and 86%, respectively. Values increased when AFP values were combined with AFP-L3% and DCP to 77%, 59%, 32%, and 91%, respectively. Among patients with increases in AFP levels to 20 to 200 ng/mL, AFP-L3% and DCP were highly specific markers (86.6% and 90.2%, respectively). Of 29 HCC patients with AFP levels less than 20 ng/mL, 13 had increased levels of AFP-L3% or DCP. Increased alanine aminotransferase levels were associated with increased total AFP but not AFP-L3% or DCP levels. Both AFP-L3%- and DCP-positive patients showed significant differences in lower cumulative HCC-free rates compared with the overall group (P < .0001 and P = .0005, respectively).

CONCLUSIONS

AFP-L3% and DCP levels have higher correlation values with an absence of HCC, as well as a higher specificity and negative predictive value, than total AFP. Although this combination of markers only marginally improves surveillance for early HCC, it could identify individuals with negative imaging results who would benefit from follow-up evaluation.

Capillary electrophoresis-electrospray ionization mass spectrometry for rapid and sensitive N-glycan analysis of glycoproteins as 9-fluorenylmethyl derivatives

It is well known that most protein therapeutics such as monoclonal antibody pharmaceuticals and other biopharmaceuticals including cancer biomarkers are glycoproteins, and thus the development of high-throughput and sensitive analytical methods for glycans is essential in terms of their determination and quality control. We previously reported a novel alternative labeling method for glycans involving 9-fluorenylmethyl chloroformate (Fmoc-Cl) instead of the conventional reductive amination procedure. The derivatives were analyzed by high-performance liquid chromatography (HPLC) (Kamoda S, Nakano M, Ishikawa R, Suzuki S, Kakehi K. 2005. Rapid and sensitive screening of N-glycans as 9-fluorenylmethyl derivatives by high-performance liquid chromatography: A method which can recover free oligosaccharides after analysis. J Proteome Res. 4:146-152). This method was rapid and simple; however, it was time-consuming in terms of analysis by HPLC and did not provide so much information such as the detailed structures and mass numbers of glycans. Here we have developed a high-throughput and highly sensitive method. It comprises three steps, i.e., release of glycans, derivatization with Fmoc, and capillary electrophoresis-electrospray ionization mass spectrometry (CE-ESI MS) analysis. We analyzed several glycoproteins such as fetuin, alpha1 acid glycoprotein, IgG, and transferrin in order to validate this method. We were able to analyze the above glycoproteins with the three-step procedure within only 5 h, which provided detailed N-glycan patterns. Moreover, the MS/MS analysis allowed identification of the N-glycan structures. As novel applications, the method was employed for the analysis of N-glycans derived from monoclonal antibody pharmaceuticals and also from alpha-fetoprotein; the latter is known as one of the tumor markers of hepatocellular carcinomas. We were able to easily and rapidly determine the detailed structures of the N-glycans. The present method is very useful for the analysis of large numbers of samples such as a routine analysis.

Des-gamma-carboxyprothrombin, alpha-fetoprotein and AFP-L3 in patients with chronic hepatitis, cirrhosis and hepatocellular carcinoma

BACKGROUND AND AIM

Hepatocellular carcinoma (HCC) is a common complication in patients with chronic viral hepatitis. Detection of HCC at an early stage is critical for a favorable clinical outcome. The study aim was to: (i) compare the levels of des-gamma-carboxyprothrombin (DCP), alpha-fetoprotein (AFP) and AFP-L3 in HCC patients and in chronic viral hepatitis patients without HCC; (ii) define the level of each tumor marker with the best sensitivity and specificity for HCC diagnosis; and (iii) to correlate the levels of these markers with respect to size and tumor burden.

METHODS

Two hundred and forty patients with either hepatitis B virus (HBV) or hepatitis C virus (HCV) infection were studied. These included 144 with HCC, 47 with chronic hepatitis (fibrosis stage I-III on liver biopsy) and 49 with cirrhosis.

RESULTS

Levels of DCP, AFP and AFP L-3 were significantly higher in patients with HCC than in those without HCC (P < or = 0.0001). Receiver-operating curves (ROC) indicated that the cut-off value with the best sensitivity and specificity for each test was > or =84 mAU/mL for DCP, > or =25 ng/mL for AFP and > or =10% for AFP-L3. The sensitivity, specificity and positive predictive value (PPV) for DCP was 87%, 85% and 86.8%, for AFP 69%, 87% and 69.8%, and for AFP-L3 56%, 90% and 56.1%, respectively. DCP levels were below the ROC cut-off in all patients without HCC. In patients with single lesions, there was a direct correlation of DCP to tumor size. High levels of AFP correlated with diffuse type of HCC. All three markers were significantly elevated in the presence of metastatic HCC. No advantage was observed by combining two or three markers for HCC diagnosis.

CONCLUSION

DCP had the highest sensitivity and PPV for HCC diagnosis, had a direct correlation with tumor size, and was not elevated in any patients without HCC. DCP should be used as the main serum test for HCC detection.

The Potentials of Glycomics in Biomarker Discovery

Introduction

Glycans have unique characteristics that are significantly different from nucleic acids and proteins in terms of biosynthesis, structures, and functions. Moreover, their isomeric nature and the complex linkages between residues have made glycan analysis a challenging task. Disease development and progression are usually associated with alternations in glycosylation on tissue proteins and/or blood proteins. Glycans released from tissue/blood proteins hence provide a valuable source of biomarkers. In this postgenome era, glycomics is an emerging research field. Glycome refers to a repertoire of glycans in a tissue/cell type, while glycomics is the study of glycome. In the past few years, attempts have been made to develop novel methodologies for quantitative glycomic profiling and to identify potential glycobiomarkers. It can be foreseen that glycomics holds the promise for biomarker discovery. This review provides an overview of the unique features of glycans and the historical applications of such features to biomarker discovery.

Future Prospective

The concept of glycomics and its recent advancement and future prospective in biomarker research are reviewed. Above all, there is no doubt that glycomics is gaining momentum in biomarker research.

Substitution of amino acid 70 in the hepatitis C virus core region of genotype 1b is an important predictor of elevated alpha-fetoprotein in patients without hepatocellular carcinoma

Previous studies identified amino acid (aa) substitutions of the hepatitis C virus core region of genotype 1b (HCV-1b core region) and elevated serum alpha-fetoprotein (AFP) levels as predictors of poor virologic response to pegylated interferon (PEG-IFN) plus ribavirin (RBV), and also as risk factors for hepatocarcinogenesis. The present study evaluated the impact of aa substitutions of HCV-1b core region on AFP, as a surrogate marker of hepatocarcinogenesis, on AFP levels in 569 Japanese patients with HCV-1b but without HCC, and investigated the predictive factors of elevated AFP (> or =11 microg/L). High AFP levels were detected in 27.4% of the patients. The rate of hepatocarcinogenesis in a group of 109 patients who received IFN monotherapy and followed-up for 15 years, was significantly higher in patients with abnormal than normal AFP. Multivariate analysis of 569 patients identified fibrosis stage (F3,4), aspartate aminotransferase (> or =76 IU/L), substitution of aa 70 (glutamine or histidine), and platelet count (<15.0 x 10(4)/microl) as significant determinants of elevated AFP. In 49 patients with abnormal AFP levels and substitutions at aa 70 who were treated with PEG-IFN + RBV, the rate of normalization of AFP was significantly lower in non-virological responders (28.6%) than in transient (71.4%) and sustained (100%) virological responders. The results indicated that substitution of aa 70 of HCV-1b core region is an important predictor of elevated AFP in non-HCC patients, and that eradication of the mutant virus normalizes AFP. The results highlight the importance of eradication of mutant type virus of aa 70 for reducing the risk of hepatocarcinogenesis.

Focused differential glycan analysis with the platform antibody-assisted lectin profiling for glycan-related biomarker verification

Protein glycosylation is a critical subject attracting increasing attention in the field of proteomics as it is expected to play a key role in the investigation of histological and diagnostic biomarkers. In this context, an enormous number of glycoproteins have now been nominated as disease-related biomarkers. However, there is no appropriate strategy in the current proteome platform to qualify such marker candidate molecules, which relates their specific expression to particular diseases. Here, we present a new practical system for focused differential glycan analysis in terms of antibody-assisted lectin profiling (ALP). In the developed procedure, (i) a target protein is enriched from clinic samples (e.g. tissue extracts, cell supernatants, or sera) by immunoprecipitation with a specific antibody recognizing a core protein moiety; (ii) the target glycoprotein is quantified by immunoblotting using the same antibody used in (i); and (iii) glycosylation difference is analyzed by means of antibody-overlay lectin microarray, an application technique of an emerging glycan profiling microarray. As model glycoproteins having either N-linked or O-linked glycans, prostate-specific antigen or podoplanin, respectively, were subjected to systematic ALP analysis. As a result, specific signals corresponding to the target glycoprotein glycans were obtained at a sub-picomole level with the aid of specific antibodies, whereby disease-specific or tissue-specific glycosylation changes could be observed in a rapid, reproducible, and high-throughput manner. Thus, the established system should provide a powerful pipeline in support of on-going efforts in glyco-biomarker discovery.

Functional roles of N-glycans in cell signaling and cell adhesion in cancer

Glycosylation is one of the most common post-translational modification reactions and nearly half of all known proteins in eukaryotes are glycosylated. In fact, changes in oligosaccharide structures are associated with many physiological and pathological events, including cell growth, migration, differentiation, tumor invasion, host-pathogen interactions, cell trafficking, and transmembrane signaling. Emerging roles of glycan functions have been highly attractive to scientists in various fields of life science as they open a field, "Functional Glycomics", that is a comprehensive study of the glycan structures in relation to functions. In particular, the N-glycans of signaling molecules including receptors or adhesion molecules are considered to be involved in cellular functions. This review will focus on the roles of glycosyltransferases involved in the biosynthesis of N-glycan branching and identification of cell surface receptors as their target proteins. We also suggest that the modulation of N-glycans of those receptors alters their important functions such as cell signaling and cell adhesion which are implicated in cancer invasion and metastasis.

Recent advances in tumor markers of human hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most devastating malignancies in the world and is the third most common cause of cancer-related death in Korea. Because most HCC are accompanied by chronic liver disease that results from hepatitis B or C viruses, prognosis is still poor even after surgical resection of the tumor. Moreover, diagnosis of advanced HCC still leads to an extremely bleak prognosis. Earlier detection of HCC, therefore, could improve patient survival. Accordingly, the development of tumor markers that can detect HCC at even earlier stages is essential. The functions of tumor markers include prediction of prognosis or therapeutic response as well as diagnosis or screening of cancer. Possible candidate tumor markers may be quantitative alterations in DNA-, RNA- or protein-based molecules in tumorous conditions assessed by various technologies, e.g. serological assays, microarrays, mass spectrometry and proteomics. However, validation and clinical implementation is needed after the discovery of novel genes. An ideal tumor marker for HCC would be sensitive and specific enabling to differentiate it at an early stage from premalignant lesions like dysplastic nodules. In addition, the marker should be easily measurable, reproducible and minimally invasive. Although it is important to identify new biomarkers for HCC, the validation and cost-effectiveness of those markers as diagnostic or prognostic tools need confirmation in large-scale studies in clinical practice.

Increased bisecting and core-fucosylated N-glycans on mutant human amyloid precursor proteins

Alteration of glycoprotein glycans often changes various properties of the glycoprotein. To understand the significance of N-glycosylation in the pathogenesis of early-onset familial Alzheimer's disease (AD) and in beta-amyloid (Abeta) production, we examined whether the mutations in the amyloid precursor protein (APP) gene found in familial AD affect the N-glycans on APP. We purified the secreted forms of wild-type and mutant human APPs (both the Swedish type and the London type) produced by transfected C17 cells and determined the N-glycan structures of these three recombinant APPs. Although the major N-glycan species of the three APPs were similar, both mutant APPs contained higher contents of bisecting N-acetylglucosamine and core-fucose residues as compared to wild-type APP. These results demonstrate that familial AD mutations in the polypeptide backbone of APP can affect processing of the attached N-glycans; however, whether these changes in N-glycosylation affect Abeta production remains to be established.

Diagnosing and monitoring hepatocellular carcinoma with alpha-fetoprotein: new aspects and applications

Hepatocellular carcinoma is the 5th most common cancer in the world. Prognosis for this disease is poor since hepatocellular carcinoma is mostly diagnosed at an advanced stage. Serum alpha-fetoprotein (AFP) is one of the most common diagnostic markers for hepatocellular carcinoma. However, its diagnostic value is more and more questioned. Therefore, research has focussed on AFP related parameters (AFP mRNA and AFP glycoforms). The aim of this paper is to review the present knowledge on AFP and its related parameters in diagnosing and monitoring HCC. AFP related parameters can be arranged in two types: AFP mRNA and AFP glycoforms. AFP mRNA is a potentially prognostic marker and AFP mRNA assays are based on PCR techniques. The AFP glycoforms have diagnostic potential and assays are based on isoelectric focussing and lectin affinity electrophoretic methods. Up to now the diagnostic use of the AFP related parameters is limited. Although some of them are recommended as a complementary test, they cannot (yet) replace serum AFP as the golden standard of diagnostic markers for hepatocellular carcinoma.

Current role of ultrasound for the management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has a decisive influence on the prognosis of cirrhotic patients. Although α-fetoprotein (AFP) is a known and specific tumor maker for HCC, it is not suitable for the screening and surveillance of HCC because of its poor predictive value and low sensitivity. The use of imaging modalities is essential for the screening, diagnosis and treatment of HCC. Ultrasound (US) plays a major role among them, because it provides real-time and non-invasive observation by a simple and easy technique. In addition, US-guided needle puncture methods are frequently required for the diagnosis and/or treatment process of HCC. The development of digital technology has led to the detection of blood flow by color Doppler US, and the sensitivity for detecting tumor vascularity has shown remarkable improvement with the introduction of microbubble contrast agents. Moreover, near real-time 3-dimensional US images are now available. As for the treatment of HCC, high intensity focused ultrasound (HIFU) was developed as a novel technology that provides a transcutaneous ablation effect without needle puncture. These advancements in the US field have led to rapid progress in HCC management, and continuing advances are expected. This article reviews the current application of US for HCC in clinical practice.

Diagnostic accuracy of tumor markers for hepatocellular carcinoma: a systematic review

Background and aims The role of alphafetoprotein (AFP) in the diagnosis and surveillance of hepatocellular carcinoma (HCC) is getting smaller owing to the advances in imaging modalities. The aims of this study were to assess the diagnostic accuracy of tumor markers in small HCC and to find the optimal cutoff value of each tumor marker for efficient surveillance. Methods Studies in all languages were identified by searching MEDLINE from 1982 to 2002. Studies were included when they showed sensitivity and specificity for HCCs 5 cm or smaller and recruited only patients with chronic hepatitis or liver cirrhosis as control. We assessed diagnostic odds ratios (DORs) for the evaluation of diagnostic accuracy of tumor markers and positive likelihood ratios (LRs+) to find the optimal cutoff value. DORs and LRs+ were combined according to the random effect model. The summary receiver operating characteristics (ROC) curve was also assessed. Results Seventeen articles on three tumor markers-AFP, des-gamma-carboxyprothrombin (DCP), and Lens culinaris agglutinin-reactive fraction of AFP (AFP-L3)-were enrolled after full-text evaluation. AFP was inferior to DCP and AFP-L3 in both DOR (4.50 vs. 8.16 and 10.50) and area under the ROC curve (0.647 vs. 0.688 and 0.695). Optimal cutoff values that provide the best LR+ were 200 ng/ml for AFP, 40 mAU/ml for DCP, and 15% for AFP-L3. Conclusions Diagnostic accuracy of AFP in small HCC was substantially limited. Surveillance including other tumor markers with optimal cutoff value should be conducted to confirm the efficacy of the policy.

Clinical significance of elevated alpha-fetoprotein in Alaskan Native patients with chronic hepatitis C

The clinical significance of elevated serum alpha-fetoprotein (AFP) in patients with chronic hepatitis C virus (HCV) infection is not well defined. We analysed data from a population-based cohort of patients with HCV infection to assess the prevalence of elevated serum AFP, to determine its association with clinical and virologic parameters and with clinical outcomes. We defined a slightly elevated serum AFP level as 8 to <15 and a high-AFP level as > or =15 microg/L. Among 541 HCV-RNA-positive persons, 61 (11%) had a slightly elevated or high AFP at the time of consent. AFP > or =8 microg/L was associated with the older age, aspartate aminotransferase/alanine aminotransferase ratio >1, and higher alkaline phosphatase levels, but not with heavy alcohol use, IV drug use, genotype, viral load or duration of HCV infection. Among 192 persons with an AFP at liver biopsy, 17% had an AFP > or =8 microg/L. The sensitivity/specificity of an AFP level > or =8 in detecting Ishak 3-6 fibrosis was 39%/95%. Among 372 persons with a minimum of four AFP measurements over 6 years, 5% had persistently elevated AFP >8 microg/L, 19% had both elevated and normal AFP measurements, and 76% had persistently normal AFP. Elevated AFP at consent was associated with hepatocellular carcinoma (HCC) and end-stage liver disease. Over 6 years of follow-up, persistently elevated AFP was associated with the development of HCC; no person with AFP persistently <8 microg/mL developed HCC. Serial AFP measurements appear to be useful in identifying persons with advanced fibrosis and help to determine who needs periodic screening with liver ultrasound to detect HCC.

Lens culinaris agglutinin-reactive alpha-fetoprotein and protein induced by vitamin K absence II are potential indicators of a poor prognosis: a histopathological study of surgically resected hepatocellular carcinoma

BACKGROUND

We histopathologically examined Lens culinaris agglutinin-reactive alpha-fetoprotein (AFP-L3)-positive hepatocellular carcinoma (HCC) and protein induced by vitamin K absence (PIVKA) II-positive HCC to clarify the efficacy of these markers for predicting a poor prognosis.

METHODS

Serum AFP-L3 and PIVKA II was measured in 110 HCC patients. AFP-L3 was measured by lectin-affinity electrophoresis coupled with antibody-affinity blotting, and PIVKA II by using a high-sensitivity kit. The growth type, capsule formation, capsule infiltration, portal vein invasion, intrahepatic metastasis and histological tumor grade were evaluated pathologically.

RESULTS

Thirty-eight (35%) HCC patients were AFP-L3-positive, and 63 (57%) were PIVKA II-positive. In AFP-L3-positive HCC, the frequencies of an infiltrative growth type (positive : negative = 66% : 42%, P = 0.027) and a poorly differentiated type (positive : negative = 32% : 6%, P < 0.001) were significantly higher than in AFP-L3-negative HCC. In PIVKA II-positive HCC, the frequencies of an infiltrative growth type (positive : negative = 62% : 28%, P < 0.001), vascular invasion (positive : negative = 63% : 26%, P < 0.001), and intrahepatic metastasis (positive : negative = 38% : 4%, P < 0.001) were significantly higher than in PIVKA II-negative HCC. In both AFP-L3- and PIVKA II-positive HCC, the frequency of a poorly differentiated growth type was significantly higher than in HCC positive for either AFP-L3 or PIVKA II or HCC negative for both AFP-L3 and PIVKA II (both positive : either positive : both negative = 37% : 12% : 0%; P = 0.014, P < 0.001, respectively).

CONCLUSIONS

AFP-L3 was related to progression from moderately differentiated to poorly differentiated HCC, whereas PIVKA II was more specific to vascular invasion. PIVKA II is therefore likely to be a useful indicator of vascular invasion.

Surveillance for hepatocellular carcinoma and early diagnosis

Good management of patients at risk for the development of hepatocellular carcinoma includes regular ultrasound surveillance, and aggressive management of lesions detected at ultrasound. Good radiology and good pathology are essential to the appropriate management of these small lesions. With good quality testing it is possible to cure the majority of HCCs using minimally invasive techniques such as radiofrequency ablation. Such an approach has the potential to convert HCC from a disease in which incidence more or less equaled mortality to one in which cure is frequently possible.

Angiopoietin-2 serum levels are elevated in patients with liver cirrhosis and hepatocellular carcinoma

OBJECTIVES

Liver cirrhosis is characterized by remodeling leading to nodules that are difficult to discern from hepatocellular carcinoma (HCC). Alpha-fetoprotein (AFP) serum levels are used for the screening for HCC, with limited success. We evaluated angiopoietin-2 as a serum marker in patients with cirrhosis and with HCC.

METHODS

In a retrospective study, we measured angiopoietin-2 serum levels in 131 patients with HCC, 180 patients with cirrhosis, and 40 healthy controls. We also determined AFP serum levels in patients with HCC and compared the test characteristics of both serum markers. The expression patterns of angiopoietin-2 were determined by in situ hybridization in healthy and cirrhotic livers as well as in HCC.

RESULTS

Angiopoietin-2 serum levels were elevated in patients with liver cirrhosis (P < 0.0001) compared with healthy controls. Levels were further elevated in patients with HCC compared with healthy controls (P < 0.0001) and cirrhotic patients (P < 0.0001). The combination with AFP measurements led to improved discrimination between HCC and cirrhosis. Angiopoietin-2 message was present in tumor cells of HCCs but was absent from hepatocytes of cirrhotic and healthy livers. In cirrhosis, message was detected within the strands of fibrous tissue.

CONCLUSIONS

Serum angiopoietin-2 levels are elevated in patients with cirrhosis, implicating a possible role of the angiopoietin-Tie-2 system for neoangiogenesis in cirrhosis. Serum levels are further elevated in patients with HCC, suggesting the potential use of angiopoietin-2 as a marker for the detection of cirrhosis and HCC.

Phenotype changes of Fut8 knockout mouse: core fucosylation is crucial for the function of growth factor receptor(s)

Alpha1,6-fucosyltransferase (Fut8) catalyzes the transfer of a fucose residue to N-linked oligosaccharides on glycoproteins by means of an alpha1,6-linkage to form core fucosylation in mammals. In mice, disruption of Fut8 induces severe growth retardation, early death during postnatal development, and emphysema-like changes in the lung. A marked dysregulation of TGF-beta1 receptor activation and signaling in Fut8-null mice lung results in overexpression of matrix metalloproteinases (MMPs), such as MMP12 and MMP13, and a down-regulation of extracellular matrix (ECM) proteins such as elastin, which contributes to the destructive emphysema-like phenotype observed in Fut8-null mice. Furthermore, therapeutic administration of exogenous TGF-beta1 rescued the null mice from the emphysema-like phenotype. On the other hand, absence of Fut8 on EGF or PDGF receptor results in down-regulation of the receptor-mediated signaling, which is a plausible factor that may be responsible for the growth retardation. Reintroduction of the Fut8 gene to Fut8-null cells potentially rescued these receptor-mediated signaling impaired in null cells. Collectively, these results suggest that core fucosylation is crucial for growth factor receptors such as TGF-beta1 and EGF receptor-mediated biological functions.

Clinical utility of AFP-L3% measurement in North American patients with HCV-related cirrhosis

BACKGROUND AND AIMS

Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3%) has been reported to be useful in the early detection of hepatocellular carcinoma (HCC) in Japan. The aim of this prospective study was to compare the clinical utility of AFP-L3% with that of total AFP in North American patients.

METHODS

Patients with chronic hepatitis (CH) C virus-related cirrhosis from 7 clinical sites were prospectively followed every 3-6 months for 2 yr.

RESULTS

Of the 372 patients evaluated, 40 had hepatitis C virus-related HCC at entry and 332 entered the prospective trial. Of the latter, 34 developed HCC and 298 remained free of HCC. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for AFP were 60.8%, 71.1%, 34.4%, and 88.0% with a cutoff of 20 ng/mL and 21.6%, 98.7%, 80.0%, and 83.5% with a cutoff of 200 ng/mL, compared to 36.5%, 91.6%, 51.9%, and 85.3% for AFP-L3% with a cutoff of 10%. In those with an elevated AFP (20-200 ng/mL), AFP-L3% had a specificity of 86.6% and an NPV of 80.7%. Multivariate analysis identified AFP, AFP-L3%, and age as independent predictors of HCC. Elevated AFP-L3% was associated with a lower cumulative HCC-free rate at 2 yr (58.9%) than was AFP (82.0%, P= 0.01).

CONCLUSIONS

The incidence of HCC was significantly higher in patients with elevated AFP-L3% than in those with elevated AFP. The high specificity of AFP-L3% persisted among patients with elevated AFP (20-200 ng/mL) and suggests that AFP-L3% has clinical utility in HCV patients with AFP of 20-200 ng/mL.

Screening for hepatocellular carcinoma

This article reviews methodological issues around screening for hepatocellular carcinoma, and discusses selection of the at-risk group, which screening test to use, and how frequently it should be applied. Screening of patients at risk for hepatocellular carcinoma should be undertaken using ultrasonography applied at six-month intervals. Patients at risk include all those with cirrhosis, and certain non-cirrhotic patients withchronic hepatitis B. In this population, screening has been shown to reduce disease-specific mortality. Although data do not exist for other populations, screening is nonetheless advised because small cancers can be cured with appreciable frequency.

Determination of trace α-fetoprotein variant by affinity adsorption solid substrate-room temperature phosphorimetry and its application to the forecast of human diseases

In the presence of ion perturber LiAc, 4-generation polyamidoamine dendrimers (4G-D) could emit strong and stable room temperature phosphorescence (RTP) signal at lambda(max)(ex)/lambda(max)(em) = 511.8/675.3 nm on nitrocellulose membrane (NCM), and Triton X-100 could sharply enhance the RTP signal of 4G-D. Triton X-100-4G-D was used to label concanavalin agglutinin (Con A) to get the labeling product Triton X-100-4G-D-Con A. Quantitative specific affinity adsorption (AA) reaction between Triton X-100-4G-D-Con A and alpha-fetoprotein variant (AFP-V) could be carried out on the surface of NCM, whose product Triton X-100-4G-D-Con A-AFP-V could emit strong and stable RTP and its deltaI(p) was proportional to the content of AFP-V. According to the facts above, a new affinity adsorption solid substrate-room temperature phosphorimetry (AA-SS-RTP) for the determination of trace AFP-V by Con A labeled with Triton X-100-4G-D was established. Detection limits of this method were 0.23 fg spot(-1) (direct method, corresponding concentration: 5.8x10(-13) g mL(-1)) and 0.13 fg spot(-1) (sandwich method, corresponding concentration: 3.2x10(-13) g mL(-1)). It has been successfully applied to determine the content of AFP-V in human serum and forecast human diseases, for its high sensitivity, long RTP lifetime, good repeatability, high accuracy and little background perturbation with lambda(max)(em) at the long wavelength area. Meanwhile, the mechanism for the determination of trace AFP-V using AA-SS-RTP was also discussed.

Serum α-Foetoprotein Level Predicts Treatment Outcome in Chronic Hepatitis C

Objectives

To analyse the association between serum α-foetoprotein (AFP) levels and sustained virological response (SVR) in treated patients.

Methods

One-hundred patients with chronic hepatitis C were treated with pegylated interferon α-2a plus ribavirin for 48 weeks. The primary endpoint was SVR. Linear regression analysis was performed to identify clinical, biological, and histological factors affecting baseline AFP levels. The association between pretreatment serum AFP and SVR was assessed by multivariate logistic regression analysis.

Results

Of 100 patients, 95 were infected with genotype 4, one with genotype 1, and four with undetermined genotype. The median serum AFP level was 4.5 ng/ml and AFP values ranged from 1.2 to 49.8 ng/ml. In multivariate analysis, higher fibrosis stage and higher steatosis score were independently associated with higher serum AFP levels. SVR rate was 61.0% (61/100), and was lower for patients with AFP levels above rather than below the median value (40.8% versus 80.4%, respectively, P<0.001). In multivariate analysis, including adjustment for age, gender, body mass index, steatosis score, fibrosis stage, ALT level, haemoglobin level, clotting time, HCV RNA viral load, and treatment dose received, a baseline serum AFP level above the median value was associated with a lower SVR rate (OR [95% CI]=0.10 [0.03–0.42], P<0.001). None of the seven patients with increased (above 15 ng/ml) pretreatment AFP achieved SVR.

Conclusions

In this study, higher baseline serum AFP levels independently predicted a lower SVR rate among patients with chronic hepatitis C. If confirmed with genotypes other than 4, these findings would suggest adding serum AFP to the list of factors predictive of treatment response.

Direct On-Membrane Glycoproteomic Approach Using MALDI-TOF Mass Spectrometry Coupled with Microdispensing of Multiple Enzymes

We report a novel approach for direct on-membrane glycoproteomics by digestion of membrane-blotted glycoproteins with multiple enzymes using piezoelectric chemical inkjet printing technology and on-membrane direct MALDI-TOF mass spectrometry. With this approach, both N-linked glycan analyses and peptide mass fingerprinting of several standard glycoproteins were successfully performed using PNGase F and trypsin microscale digestions of the blotted spots on membrane from an SDS-PAGE gel. In addition, we performed a similar analysis for 2-DE separated serum glycoproteins as a demonstration of how the system could be used in human plasma glycoproteomics.

Predictors of alpha-fetoprotein elevation in patients with chronic hepatitis C, but not hepatocellular carcinoma, and its normalization after pegylated interferon alfa 2a-ribavirin combination therapy

BACKGROUND AND AIM

Elevated serum alpha-fetoprotein (AFP) levels are noted in patients with chronic hepatitis C (CHC) without hepatocellular carcinoma (HCC). The change in AFP levels after treatment with pegylated interferon and ribavirin (Peg-IFN/RBV) combination therapy is still unknown. The aim of this study was to investigate the predictors of elevated serum AFP in patients with CHC, and its change after Peg-IFN/RBV therapy.

METHODS

A total of 123 patients, intended to receive pegylated interferon alfa-2a plus ribavirin therapy, were enrolled. Eighty-three patients had complete treatment and received follow up for and additional 24 weeks. The factors that may affect the elevation of pretreatment AFP and the normalization of post-treatment AFP were determined.

RESULTS

The mean AFP level was 18.5 +/- 63.0 ng/mL (range, 1.3-676.0 ng/mL); 41 (33.3%) of the 123 patients had elevated serum AFP (more than 10 ng/mL) at baseline. A multivariate logistic regression analysis disclosed that older age (odds ratio [OR], 1.093; 95% confidence interval [CI], 1.015-1.177; P = 0.018), more advanced METAVIR fibrosis stage (OR, 5.237; 95% CI, 1.244-22.037; P = 0.024), a higher aspartate aminotransferase (AST) level (IU/L) (OR, 1.020; 95% CI, 1.008-1.033; P = 0.001), and lower platelet count (x10(9)/L, OR, 0.985; 95% CI, 0.968-0.994; P = 0.003) were independent determinants of pretreatment AFP elevation. After treatment, 72 of 83 (86.7%) cases were found to have normal post-treatment AFP levels (<10 ng/mL) at the end of follow up (EOF). Post-treatment negativity of the chronic hepatitis C virus (HCV)-RNA (OR, 10.014; 95% CI, 1.000-100.329; P = 0.050) and the post-treatment platelet count (x10(9)/L) (OR, 1.025; 95% CI, 1.001-1.050; P = 0.040) were associated with normal AFP at EOF. AFP progressively decreased with significant differences starting from the 12th week after treatment to the end of treatment, and was lowest at the EOF date for the sustained viral response (SVR) group. On the contrary, the non-SVR group did not have an AFP change during and after treatment.

CONCLUSION

Older age, low platelet count, higher AST levels, and advanced fibrosis predisposed chronic hepatitis C patients without HCC to have elevated serum AFP levels. After Peg-IFN/RBV combination therapy, a higher platelet count and HCV viral eradication were determinants of normal AFP at EOF. Serial AFP levels decreased after treatment, presenting in a time-dependent manner, specifically for the SVR group.

Clinical evaluation of lens culinaris agglutinin-reactive alpha-fetoprotein and des-gamma-carboxy prothrombin in histologically proven hepatocellular carcinoma in the United States

There is no established clinical role for the lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3%) and des-gamma-carboxy prothrombin (DCP) in the management of the U.S. hepatocellular carcinoma (HCC) patient population. In order to clarify the clinical usefulness and characteristics of AFP-L3% and DCP, a prospective study was performed on United States patients having histologically proven hepatocellular carcinoma. Ninety-nine histologically proven HCC patients, who were diagnosed with unresectable cancer between July 1999 and March 2001 at the Liver Cancer Center of the University of Pittsburgh Medical Center, were included for analysis. The sensitivity of AFP-L3%, DCP, and AFP was 61.6%, 72.7%, and 67.7%, respectively. The highest sensitivity, 85.9%, was obtained in the combination of three markers. Statistically significant differences were observed for portal vein invasion in AFP-L3% and AFP levels (P = 0.0059 and P = 0.0360, respectively). DCP was significantly associated with metastasis (P = 0.0368). There were significant associations between AFP-L3% and AFP results and patient survival (P = 0.0150 and P = 0.0020, respectively). AFP-L3%, platelet count,and albumin showed a significant difference with respect to outcomes on Cox's proportional hazard model (P = 0.0059, P = 0.0073, and P = 0.0265, respectively). The combination of AFP-L3%, DCP, and AFP was determined to be superior for detection of HCC compared with each marker alone or to other combinations. AFP-L3% was significantly related to portal vein invasion and patient outcomes and appears to be a useful prognostic marker for HCC.

The utility of Lens culinaris agglutinin-reactive alpha-fetoprotein in the diagnosis of hepatocellular carcinoma: evaluation in a United States referral population

BACKGROUND & AIMS

The percentage of Lens culinaris agglutinin-reactive (alpha)-fetoprotein (AFP-L3%) is proposed as a diagnostic and prognostic marker for hepatocellular carcinoma (HCC). We evaluated the utility of AFP-L3% for diagnosis of HCC in a US referral population.

METHODS

This retrospective study included 272 patients: 166 with HCC and 106 with benign liver disease (chronic liver disease, 77; benign liver mass, 29). The AFP-L3% was measured using a clinical auto-analyzer.

RESULTS

The AFP-L3% is not reported for a total alpha-fetoprotein (AFP) less than 10 ng/mL, and all patients with an AFP greater than 200 ng/mL had HCC; thus the AFP-L3% was noninformative for these patients. In patients with a total AFP of 10-200 ng/mL, an AFP-L3% greater than 10% had a sensitivity of 71% and a specificity of 63% for diagnosis of HCC. An AFP-L3% greater than 35% had a reduced sensitivity of 33%, but an increased specificity of 100%. The high specificity of the AFP-L3% cut-off of 35% allowed the confident diagnosis of an additional 10% of HCCs not diagnosed using an AFP cut-off of 200 ng/mL. After adjustment for AFP level, no association was observed between AFP-L3% and tumor size, stage, vascular invasion, grade, or survival.

CONCLUSIONS

Patients with indeterminate total AFP values of 10-200 ng/mL present a diagnostic dilemma. We found that an AFP-L3% greater than 35% has 100% specificity for HCC in these patients. AFP-L3%, used in combination with AFP, may be a clinically useful adjunct marker for the diagnosis of HCC.

A concise review of serum markers for hepatocellular cancer

BACKGROUND

The rising incidence of hepatocellular cancer in the US and worldwide has sparked a renewed interest in HCC serum markers. HCC typically develops in patients with chronic liver disease and cirrhosis. It is in these target populations that serum markers are most urgently needed. Unfortunately, the currently available markers lack sensitivity and specificity. A number of novel candidate markers have recently been introduced.

METHODS

We performed a review of the literature (2001-2006) of traditional and novel serum markers for hepatocellular cancer.

RESULTS

Several promising new HCC markers have been identified over the past 5 years. They include single proteins, complex proteomics features, and tumor-specific autoantibodies. The excitement about the new markers is tempered by the realization that none of them have yet met the most stringent criteria defined by the Early Detection Research Network (EDRN).

CONCLUSION

A new generation of HCC serum markers awaits validation in properly controlled clinical studies.

The progressive elevation of alpha fetoprotein for the diagnosis of hepatocellular carcinoma in patients with liver cirrhosis

Background

Hepatocellular carcinoma is the most common cause of primary liver neoplasms and is one of the main causes of death in patients with liver cirrhosis. High Alpha fetoprotein serum levels have been found in 60–70% of patients with Hepatocellular carcinoma; nevertheless, there are other causes that increase this protein. Alpha fetoprotein levels ≥200 and 400 ng/mL in patients with an identifiable liver mass by imaging techniques are diagnostic of hepatocellular carcinoma with high specificity.

Methods

We analysed the sensitivity and specificity of the progressive increase of the levels of alpha fetoprotein for the detection of hepatocellular carcinoma in patients with liver cirrhosis. Seventy-four patients with cirrhosis without hepatocellular carcinoma and 193 with hepatic lesions diagnosed by biopsy and shown by image scans were included. Sensitivity and specificity of transversal determination of alpha fetoprotein ≥ 200 and 400 ng/mL and monthly progressive elevation of alpha fetoprotein were analysed. Areas under the ROC curves were compared. Positive and negative predictive values adjusted to a 5 and 10% prevalence were calculated.

Results

For an elevation of alpha fetoprotein ≥ 200 and 400 ng/mL the specificity is of 100% in both cases, with a sensitivity of 36.3 and 20.2%, respectively. For an alpha fetoprotein elevation rate ≥7 ng/mL/month, sensitivity was of 71.4% and specificity of 100%. The area under the ROC curve of the progressive elevation was significantly greater than that of the transversal determination of alpha fetoprotein. The positive and negative predictive values modified to a 10% prevalence are of: 98.8% and 96.92%, respectively; while for a prevalence of 5% they were of 97.4% and 98.52%, respectively.

Conclusion

The progressive elevation of alpha fetoprotein ≥7 ng/mL/month in patients with liver cirrhosis is useful for the diagnosis of hepatocellular carcinoma in patients that do not reach αFP levels ≥200 ng/mL. Prospective studies are required to confirm this observation.

The clinical utility of Lens culinaris agglutinin-reactive thyroglobulin ratio in serum for distinguishing benign from malignant conditions of the thyroid

BACKGROUND

Traditionally, the follow-up of differentiated thyroid carcinoma consists of periodic withdrawal from L-T4-suppressive therapy to allow performance of a highly sensitive serum Tg measurement to detect recurrences. We investigated Lens culinaris agglutinin-reactive thyroglobulin ratios in serum to evaluate in usefulness for detection of thyroid carcinoma.

METHODS

The study was conducted on 93 serum sample from 23 healthy volunteers, 32 patients with benign thyroid tumor, 28 patients with thyroid carcinoma without metastasis, and 10 patients with thyroid carcinoma with lymph node metastasis.

RESULTS

The Lens culinaris Agglutinin reactive thyroglobulin ratio in patients with thyroid carcinoma was significantly lower than in patients with benign thyroid tumor with serum thyroglobulin concentration >200 ng/ml. Among cases of thyroid carcinoma with lymph node metastasis, Lens culinaris Agglutinin reactive thyroglobulin ratios were significantly lower than in patient with thyroid carcinoma without metastasis and those with benign tumor regardless of serum thyroglobulin concentration.

CONCLUSION

Measurement of Lens culinaris Agglutinin reactive thyroglobulin ratio in serum may be useful for distinguishing between thyroid carcinoma and benign thyroid tumor.

Prediction of recurrence of hepatocellular carcinoma after curative ablation using three tumor markers

Three tumor markers for hepatocellular carcinoma (HCC) are available in daily practice in Japan: alpha-fetoprotein (AFP), des-gamma-carboxy prothrombin (DCP), and lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3). To elucidate the predictability of these tumor markers on HCC recurrence after curative ablation, we enrolled 416 consecutive patients with naïve HCC who had been treated by percutaneous ablation at our department from July 1997 to December 2002. Tumor marker levels were determined immediately before and 2 months after the treatment. Complete ablation was defined on CT findings as nonenhancement in the entire lesion with a safety margin. Tumor recurrence was also defined as newly developed lesions on CT that showed hyperattenuation in the arterial phase with washout in the late phase. We assessed the predictability of recurrence via tumor markers in multivariate analysis, using proportional hazard regression after adjusting for other significant factors in univariate analysis. Until the end of follow-up, tumor recurrence was identified in 277 patients. Univariate analysis revealed the following factors to be significant for recurrence: platelet count; size and number of tumors; AFP, AFP-L3, and DCP preablation; and AFP and AFP-L3 postablation. Multivariate analysis indicated that AFP >100 ng/mL and AFP-L3 >15%, both pre- and postablation, were significant predictors. The positivity of AFP and AFP-L3 preablation that turned negative postablation was not significant. In conclusion, tumor markers pre- and post-ablation were significant predictors for HCC recurrence and can complement imaging modalities in the evaluation of treatment efficacy.

From glycomics to functional glycomics of sugar chains: Identification of target proteins with functional changes using gene targeting mice and knock down cells of FUT8 as examples

Comprehensive analyses of proteins from cells and tissues are the most effective means of elucidating the expression patterns of individual disease-related proteins. On the other hand, the simultaneous separation and characterization of proteins by 1-DE or 2-DE followed by MS analysis are one of the fundamental approaches to proteomic analysis. However, these analyses do not permit the complete structural identification of glycans in glycoproteins or their structural characterization. Over half of all known proteins are glycosylated and glycan analyses of glycoproteins are requisite for fundamental proteomics studies. The analysis of glycan structural alterations in glycoproteins is becoming increasingly important in terms of biomarkers, quality control of glycoprotein drugs, and the development of new drugs. However, usual approach such as proteoglycomics, glycoproteomics and glycomics which characterizes and/or identifies sugar chains, provides some structural information, but it does not provide any information of functionality of sugar chains. Therefore, in order to elucidate the function of glycans, functional glycomics which identifies the target glycoproteins and characterizes functional roles of sugar chains represents a promising approach. In this review, we show examples of functional glycomics technique using alpha 1,6 fucosyltransferase gene (Fut8) in order to identify the target glycoprotein(s). This approach is based on glycan profiling by CE/MS and LC/MS followed by proteomic approaches, including 2-DE/1-DE and lectin blot techniques and identification of functional changes of sugar chains.

Chronic hepatitis C and screening for hepatocellular carcinoma

It is now at least theoretically possible to prevent patients with hepatocellular carcinoma (HCC) from dying of HCC. Screening identifies small potentially curable lesions, and the diagnostic algorithm allows for efficient investigation and diagnosis. Radiofrequency ablation completely ablates more than 05% of lesions smaller than 2 cm. Second primary cancers can be dealt with in the same manner as the initial primary. If the management of HCC is so efficient and effective, liver transplantation may come to be used as a last resort, rather than the treatment of choice. This benefits patients with hepatitis C and other liver diseases because more organs become available for treatment of other liver diseases.

Evaluation of clinical and biochemical parameters in hepatocellular carcinoma: Experience from an Indian center

BACKGROUND

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver. Several etiologic factors including hepatitis viruses, alcohol and aflatoxin have been implicated in the pathogenesis of HCC. However, there is limited information regarding clinicopathological profile of HCC from the Indian subcontinent.

METHODS

Forty seven patients of HCC (M=43, F=4) diagnosed on the basis of history, clinical examination, imaging (USG, CT/MRI), alpha-fetoprotein (AFP) and by USG/CT guided FNAC, were included. Patients were screened for HBV, HCV and history of alcohol. Tumor size was assessed on imaging and UGI endoscopy for the presence of varices.

RESULTS

The mean age was 53.4+/-14.6 y. Clinical presentation included anorexia in 32 (68%), abdominal pain in 28 (60%), loss of weight in 23 (49%), fever in 12 (26%), and jaundice in 6 (13%) patients. Twenty nine (62%) had underlying cirrhosis, diagnosed by ultrasound or CT. Seventeen percent had normal AFP (<10 ng/ml) and the remaining 83% had raised AFP [<10 ng/ml=7, 10-400 ng/ml=27, >400 ng/ml=8]. Thirteen patients (28%) were consuming alcohol in cirrhogenic doses and 10 (21%) were smokers. Fifty four percent were positive for HBsAg, 47% of these were also positive for HBeAg. Twenty seven percent were positive for anti-HCV. Tumor size on imaging was analyzed in 33 patients. Tumor size varied from <3 cm in 8 (18%), 3-5 cm in 12 (27%) and >5 cm in 25 (56%) patients. Twenty-three patients were lost to follow-up, 4 died and 6 did not agree for any treatment. Only 5 patients could be subjected to hepatic resection. Remaining 9 patients had a large tumor size and were put on tamoxifen.

CONCLUSION

More than half of the HCC cases have underlying cirrhosis. Hepatitis B virus infection is commonly associated. Most of patients have a large tumor (>5 cm) at presentation.

Expression of AFP and Rev-Erb A/Rev-Erb B and N-CoR in fetal rat liver, liver injury and liver regeneration

Background

Alpha-fetoprotein (AFP) expression can resume in the adult liver under pathophysiological conditions. Orphan nuclear receptors were supposed to regulate AFP gene expression, in vitro. We were interested to study the expression of AFP and orphan nuclear receptors, in vivo.

Results

The expression of AFP gene and orphan nuclear receptors in the liver was examined in different rat models: (a) fetal liver (b) liver regeneration [partial hepatectomy (PH) with and without 2-acetyl-aminofluren treatment (2-AAF)], (c) acute liver damage [treatment with CCl₄] and (d) acute phase reaction [treatment with turpentine oil]. After PH of 2-AAF treated rats, clusters of AFP positive cells occurred in the periportal region. In the Northern blot analysis, a positive hybridization signal for the full-length AFP-RNA was observed only in liver samples from 2-AAF treated rats after PH. In real-time PCR analysis, the full-length AFP-RNA was highly up regulated in the fetal liver (maximum at day 14: 21,500 fold); after PH of 2-AAF treated rats, the full-length AFP-RNA was also up regulated up to 400 fold (day 7 after PH). The orphan nuclear receptors were down regulated at nearly each time points in all models, also at time point of up regulation of the AFP gene.

Conclusion

Expression of "fetal" AFP could be demonstrated during liver development and during proliferation of the so-called oval cells. Changes of expression of orphan nuclear receptors, however, did not correlate with AFP expression. Other regulatory pathways were possibly involved in controlling AFP expression, in vivo.

Lectin-reactive alpha-fetoprotein in patients with tyrosinemia type I and hepatocellular carcinoma

Despite the introduction of 2-(2-nitro-4-trifluormethyl-benzoyl)-1,3-cyclohexandion into the treatment of hereditary tyrosinemia type I (HT1), patients remain at risk of developing hepatocellular carcinoma (HCC). Serial total alpha-fetoprotein (AFP) levels are used to monitor the individual patient. Lectin-reactive alpha-fetoprotein (L3-AFP) is an AFP isoform that is expressed by malignant liver tumors. We investigated whether the analysis of L3-AFP could lead to earlier detection of HCC in HT1 compared with judgement based on total AFP alone. AFP electrophoresis using lectin-containing agarose gel identifies L3-AFP by the affinity of its specific carbohydrate chain to lectin. We report the retrospective analysis of sequential serum samples of 12 patients with HT1 and histologically proven HCC. AFP isoforms could be identified in all 12 patients. In 6 patients, the L3-AFP increased before the total AFP. In 3 patients, the rise in L3-AFP was parallel to the rise of total AFP; and in 3 patients, the L3-AFP was raised after the total AFP or did not increase at all. We were able to identify 6 of 12 patients with an early increase in the new tumor marker. Lectin-affinity electrophoresis may have a role in discriminating benign liver disease from HCC in HT1. We suggest the further evaluation of L3-AFP in HT1.

Fucosylated haptoglobin is a novel marker for pancreatic cancer: a detailed analysis of the oligosaccharide structure and a possible mechanism for fucosylation

Changes in oligosaccharide structures have been reported in certain types of malignant transformations and, thus, could be used for tumor markers in certain types of cancer. In the case of pancreatic cancer cell lines, a variety of fucosylated proteins are secreted into their conditioned media. To identify fucosylated proteins in the serum of patients with pancreatic cancer, we performed western blot analyses using Aleuria Aurantica Lectin (AAL), which is specific for fucosylated structures. An approximately 40 kD protein was found to be highly fucosylated in pancreatic cancer and an N-terminal analysis revealed that it was the beta chain of haptoglobin. While the appearance of fucosylated haptoglobin has been reported in other diseases such as hepatocellular carcinoma, liver cirrhosis, gastric cancer and colon cancer, the incidence was significantly higher in the case of pancreatic cancer. Fucosylated haptoglobin was observed more frequently at the advanced stage of pancreatic cancer and disappeared after an operation. A mass spectrometry analysis of haptoglobin purified from the serum of patients with pancreatic cancer and the medium from a pancreatic cancer cell line, PSN-1, showed that the alpha 1-3/alpha 1-4/alpha 1-6 fucosylation of haptoglobin was increased in pancreatic cancer. When a hepatoma cell line, Hep3B, was cultured with the conditioned media from pancreatic cancer cells, haptoglobin secretion was dramatically increased. These findings suggest that fucosylated haptoglobin could serve as a novel marker for pancreatic cancer. Two possibilities were considered in terms of the fucosylation of haptoglobin. One is that pancreatic cancer cells, themselves, produce fucosylated haptoglobin; the other is that pancreatic cancer produces a factor, which induces the production of fucosylated haptoglobin in the liver.

Increased efficacy and safety in the treatment of experimental liver cancer with a novel adenovirus-alphavirus hybrid vector

An improved viral vector for cancer gene therapy should be capable of infecting tumors with high efficiency, inducing specific and high-level expression of transgene in the tumor and selectively destroying tumor cells. In the design of such a vector to treat hepatocellular carcinoma, we took advantage of (a) the high infectivity of adenoviruses for hepatic cells, (b) the high level of protein expression and proapoptotic properties that characterize Semliki Forest virus (SFV) replicon, and (c) tumor selectivity provided by alpha-fetoprotein (AFP) promoter. We constructed a hybrid viral vector composed of a helper-dependent adenovirus containing an SFV replicon under the transcriptional control of AFP promoter and a transgene driven by SFV subgenomic promoter. Hybrid vectors containing murine interleukin-12 (mIL-12) genes or reporter gene LacZ showed very specific and high-level expression of transgenes in AFP-expressing hepatocellular carcinoma cells, both in vitro and in an in vivo hepatocellular carcinoma animal model. Infected hepatocellular carcinoma cells were selectively eliminated due to the induction of apoptosis by SFV replication. In a rat orthotopic liver tumor model, treatment of established tumors with a hybrid vector carrying mIL-12 gene resulted in strong antitumoral activity without accompanying toxicity. This new type of hybrid vectors may provide a potent and safe tool for cancer gene therapy.

Core fucosylation regulates epidermal growth factor receptor-mediated intracellular signaling

alpha1,6-Fucosyltransferase (Fut8) catalyzes the transfer of a fucose residue to N-linked oligosaccharides on glycoproteins via an alpha1,6-linkage to form core fucosylation in mammals. We recently found that disruption of the Fut8 gene induces severe growth retardation and early postnatal death. To investigate the molecular mechanism involved, we have established embryonic fibroblasts of Fut8+/+ and Fut8-/-, derived from wild-type and Fut8-null mice, respectively. Interestingly, the epidermal growth factor (EGF)-induced phosphorylation levels of the EGF receptor (EGFR) were substantially blocked in Fut8-/- cells, compared with Fut8+/+ cells, while there are no significant changes in the total activities of tyrosine phosphatase for phosphorylated EGFR between two cells. The inhibition of EGFR phosphorylation was completely restored by re-introduction of the Fut8 gene to Fut8-/- cells. Consistent with this, EGFR-mediated JNK or ERK activation was significantly suppressed in Fut8-/- cells. Finally, we found that the core fucosylation of N-glycans is required for the binding of the EGF to its receptor, whereas no effect was observed for the expression levels of EGFR on the cell surface. Collectively, these results strongly suggest that core fucosylation is essential for EGF receptor-mediated biological functions.

Hepatocellular carcinoma in children and effect of living-donor liver transplantation on outcome

Hepatocellular carcinoma (HCC) is primarily observed in the older children and in most cases it develops in association with liver cirrhosis. Liver transplantation offers a good chance for long-term cure. To evaluate the outcome of children with HCC and the impact of living-donor orthotopic liver transplantation (OLT) on survival a retrospective review of radiographic, laboratory, pathologic, and therapeutic data in 13 children (six female and seven male) with chronic liver disease accompanied with HCC were studied. The patients were divided into two groups according to therapeutic modality: transplanted and non-transplanted patients. Kaplan-Meier survival curves in various therapeutic groups were plotted. The mean age of patients was 6.4 +/- 4.8 yr. Pediatric end-stage liver disease score was adapted to model for end-stage liver disease score for HCC and ranged between 1-44 and 18-44, respectively. The underlying liver diseases were tyrosinemia type 1 (n = 6), chronic hepatitis B infection (n = 6), glycogen storage disease type 1 (n = 1). Alfa-feto protein levels were elevated in all patients except one. Median number of tumor nodules was three (1-10), median maximal diameter of tumor nodules was 3.4 cm (0.5-8). Eleven patients were eligible for OLT whereas two patients were not eligible. Seven of the 11 patients considered for transplantation underwent living-donor OLT. Remaining four patients died while waiting on cadaveric transplant list. Overall 1 and 4-yr survival rates for all patients were 53.3 and 26.6%, respectively, and were found significantly higher in transplanted children than non-transplanted children (72%, 72% vs. 33% and 16.6%). No patient had tumor recurrence at median of 36-month follow-up after OLT. OLT is a life-saving procedure for children with chronic liver disease accompanying with HCC. Living-donor OLT avoids the risk of tumor progression and transplant ineligibility in these children.

[Early diagnosis of liver cancer]

Hepatocellular carcinoma is a frequent neoplasm that usually develops in patients with liver cirrhosis. Because it is the main cause of death in these patients, they should be included in a surveillance program in order to identify these tumors at an early stage and be able to indicate curative treatment (liver transplantation, surgical resection or percutaneous ablation therapy) and to reduce mortality. Surveillance should include determination of alpha-fetoprotein and abdominal ultrasound every 6 months. This strategy should only be applied to patients suitable to receive curative treatment if diagnosed of hepatocellular carcinoma. Using this approach, 40-80% of tumors identified are solitary at diagnosis, although only half of these patients can benefit from curative treatment.

Serum alpha-fetoprotein levels in patients with advanced hepatitis C: results from the HALT-C Trial

BACKGROUND/AIMS

Alpha-fetoprotein (AFP) has been useful in the diagnosis of hepatocellular carcinoma (HCC) but lacks specificity. We assessed serum AFP among patients with chronic hepatitis C and advanced fibrosis to establish predictors of AFP elevations and changes with antiviral therapy.

METHODS

Serum AFP was measured at baseline and on therapy in patients in the Hepatitis C Antiviral Long-Term Treatment against Cirrhosis (HALT-C). AFP levels were correlated with patient demographic and clinical features.

RESULTS

Baseline AFP was > or = 20 ng/mL in 191 of 1145 patients (16.6%). Mean AFP values were significantly higher in patients with cirrhosis than in those with bridging fibrosis (22.5 vs. 11.4 ng/mL, P < 0.0001). Factors independently associated with raised serum AFP in patients with cirrhosis were female gender, black race, decreased platelet count, increased serum AST/ALT ratio, serum ferritin, and Mallory bodies in liver biopsies. Serum AFP levels decreased significantly during therapy with pegylated interferon alpha-2a and ribavirin. HCC was identified in six subjects, only three of whom had AFP > 20 ng/mL.

CONCLUSIONS

Among patients with advanced chronic hepatitis C, serum AFP values are frequently elevated, even in the absence of HCC. Factors associated with raised AFP include severity of liver disease, female gender and black race. Serum AFP levels decline during antiviral therapy.

Prevention of second primary tumors by an acyclic retinoid in patients with hepatocellular carcinoma. Updated analysis of the long-term follow-up data

Oral administration with acyclic retinoid, a synthetic vitamin A analog, for a limited period of 12 months (48 weeks) prevented the development of second primary hepatocellular carcinoma (HCC) and also improved the survival of patients who underwent curative treatments of the initial tumor. Following that randomized controlled study reported in 1996 and 1999, we have continued to follow up the patients by medical imaging and blood chemical analyses, and found that the preventive effect of acyclic retinoid lasted up to 199 weeks after randomization (or 151 weeks after completion of retinoid administration). The retinoid's effect was not mediated by reduction in hepatic necro-inflammation since no significant decrease in serum aminotransferase activity was seen in the retinoid group. Such observation seems quite distinct from the cancer-preventive mechanism of interferon, a potent immunopreventive agent for HCC. We have also shown here the reduction by the retinoid in serum levels of lectin-reactive alpha-fetoprotein (AFP-L3) and protein induced by vitamin K absence or antagonist-II (PIVKA-II), both of which indicate the presence of latent HCC cells. These results suggest that acyclic retinoid may delete such malignant clones before they expand to clinically detectable tumors and thereby inhibited second primary HCC. Once such latent clones are eradicated, it may well take at least several years for the next cancer clone to arise clinically. This may possibly explain a reason for the long-term effect of the retinoid even after the limited period of administration.

Clinical role of tissue and serum levels of SCCA antigen in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most frequent cancer in the world and a common occurrence in patients with liver cirrhosis in western and North American countries. Ultrasound screening is a powerful technique for HCC diagnosis, whereas the only available serologic test, alpha-fetoprotein, has poor reliability. It has been reported that the squamous cell carcinoma antigen (SCCA) is overexpressed in HCC tissue. In our study, the expression of SCCA was investigated in tumoral and peritumoral tissues and in the serum of 52 HCC patients, as well as in the serum of 48 cirrhotic patients. The results show that SCCA expression is much stronger in the tumoral than in the peritumoral tissue of HCC. Moreover, it is also evident in metastatic nodules present in the peritumoral tissue. SCCA serum levels were significantly higher in HCC samples than in cirrhotic samples. However, no correlation was found between SCCA expression and the HCC histologic degree, nor did SCCA expression correlate with tumor size, presence of metastasis or clinical outcome. In conclusion, in HCC patients, the SCCA antigen could represent a useful marker for the detection of micro-metastasis in the tissues and for large-scale screening of serum in patients at risk.

Liver transplantation for malignancy

Liver transplantation for hepatic malignancies has emerged from an exotic and desperate approach to a well-documented and proven treatment modality for these unfortunate patients. However, early unsatisfactory results emphasized that only a highly selected patient population would benefit from transplantation. Currently, <10% of all liver transplants performed are for hepatocellular cancer (HCC). There is no controversy that hepatoblastoma is an excellent indication in pediatric patients with unresectable tumors. Similarly, liver transplantation for HCC in the adult population yields good results for patients whose tumor masses do not exceed the Milan criteria. It remains to be determined whether patients with more extensive tumors can be reliably selected to benefit from the procedure. Adjunctive procedures like radiofrequency ablation, chemoembolization, or cryotherapy might be indicated to limit tumor progression for patients on waiting lists. Epitheloid hemangioendothelioma is also an appropriate indication for liver transplantation, unlike angiosarcoma. Metastatic liver disease is not an indication for liver transplantation, with the exception of cases in which the primary is a neuroendocrine tumor, for which liver transplantation can result in long-term survival and even cure in a number of patients. And finally, while gallbladder cancers are never an indication for liver transplantation, rare cases of cholangiocellular cancer might qualify if aggressive combination therapies, including chemotherapy and radiotherapy followed by OLT, are carried through. Survival in these selected patients can approach that for patients with cholestatic liver disease.