Utility of lentil lectin affinity of alpha-fetoprotein in the diagnosis of hepatocellular carcinoma

Quantitative mass spectrometric analysis of hepatocellular carcinoma biomarker alpha-fetoprotein

Serum alpha-fetoprotein (AFP) has been used as a marker for the diagnosis of hepatocellular carcinoma (HCC) and its core fucosylation is associated with the early stage of HCC. However, current methods for the detection of AFP with core fucose are not highly accurate for early diagnosis. In this study, we established an enzyme-assisted mass spectrometric method for the quantitative analysis of AFP/core fucose with high specificity and sensitivity. We employed endoglycosidase treatment of AFP to improve the biomarker analysis. The accuracy and precision are within the US FDA-suggested value, and a good linearity (r2 = 0.9930) and a detection limit of 15.6 ng mL-1 can be achieved.

Ordered Labeling-Facilitated Electrochemical Assay of Alpha-Fetoprotein-L3 Ratio for Diagnosing Hepatocellular Carcinoma

Serum alpha fetoprotein (AFP) is a "gold-standard" biomarker for the diagnosis of hepatocellular carcinoma (HCC). Available pieces of evidence suggest that the ratio of AFP-L3 isoform in the total AFP may provide more accurate prediction for the incidence of HCC. In this work, we design an electrochemical aptasensor for high-accuracy assay of AFP-L3 ratio based on differentiated labeling of AFP isoforms in an orderly fashion. Specifically, total AFP is first captured by an AFP aptamer-functionalized electrode and labeled with quantum dots-functionalized DNA probes via mild reduction. Then, AFP-L3 isoform that strongly binds to Lens culinaris agglutinin is labeled with silver nanoparticles after the exonuclease-catalyzed removal of DNA probes. By tracing the electrochemical responses of quantum dots and silver nanoparticles, respectively, the amounts of total AFP and AFP-L3 isoforms are determined and the AFP-L3 ratio is accordingly calculated to favor the accurate HCC diagnosis. Experimental results prove the high-accuracy assay of AFP-L3 ratio based on the AFP quantitation in a linear range of 0.0008-40 ng mL^-1 and AFP-L3 quantitation in a linear range of 0.004-40 ng mL^-1. The aptasensor also displays satisfactory specificity and good recoveries even in the complex serum samples. Therefore, the aptasensor may provide a valuable tool for the assay of the AFP-L3 ratio and have a great potential use in early warning of HCC for clinical application.

Comparison of Fucose-Specific Lectins to Improve Quantitative AFP-L3 Assay for Diagnosing Hepatocellular Carcinoma Using Mass Spectrometry

Glycoproteins have many important biological functions. In particular, aberrant glycosylation has been observed in various cancers, such as liver cancer. A well-known glycoprotein biomarker is α-fetoprotein (AFP), a surveillance biomarker for hepatocellular carcinoma (HCC) that contains a glycosylation site at asparagine 251. The low diagnostic sensitivity of AFP led researchers to focus on AFP-L3, which has the same sequence as conventional AFP but contains a fucosylated glycan. AFP-L3 has high affinity for Lens culinaris agglutinin (LCA) lectin, prompting many groups to use it for detecting AFP-L3. However, a few studies have identified more effective lectins for fractionating AFP-L3. In this study, we compared the amounts of enriched AFP-L3 with five fucose-specific lectins─LCA, Lotus tetragonolobus lectin (LTL), Ulex europaeus agglutinin I (UEA I), Aleuria aurantia lectin (AAL), and Aspergillus oryzae lectin (AOL)─to identify better lectins and improve HCC diagnostic assays using mass spectrometry (MS). Our results indicate that LTL was the most effective lectin for capturing AFP-L3 species, yielding approximately 3-fold more AFP-L3 than LCA from the same pool of HCC serum samples. Thus, we recommend the use of LTL for AFP-L3 assays, given its potential to improve the diagnostic sensitivity in patients having limited results by conventional LCA assay. The MS data have been deposited to the PeptideAtlas (PASS01752).

Rhizoctonia bataticola lectin induces apoptosis and inhibits metastasis in ovarian cancer cells by interacting with CA 125 antigen differentially expressed on ovarian cells

A N-glycan specific lectin from Rhizoctonia bataticola [RBL] was shown to induce growth inhibitory and apoptotic effect in human ovarian, colon and leukemic cells but mitogenic effect on normal PBMCs as reported earlier, revealing its clinical potential. RBL has unique specificity for high mannose tri and tetra antennary N-glycans, expressed in ovarian cancer and also recognizes glycans which are part of CA 125 antigen, a well known ovarian cancer marker. Hence, in the present study diagnostic and therapeutic potential of RBL was investigated using human ovarian epithelial cancer SKOV3 and OVCAR3 cells known for differentially expressing CA 125. RBL binds differentially to human ovarian normal, cyst and cancer tissues. Flow cytometry, western blot analysis of membrane proteins showed the competitive binding of RBL and CA 125 antibody for the same binding sites on SKOV3 and OVCAR3 cells. RBL has strong binding to both SKOV3 and OVCAR3 cells with MFI of 173 and 155 respectively. RBL shows dose and time dependent growth inhibitory effect with IC₅₀ of 2.5 and 8 μg/mL respectively for SKOV3 and OVCAR3 cells. RBL induces reproductive cell death, morphological changes, nuclear degradation and increased release of ROS in SKOV3 and OVCAR3 cells leading to cell death. This is also supported by increase in hypodiploid population, altered MMP leading to apoptosis possibly involving intrinsic pathway. Adhesion, wound healing, invasion and migration assays demonstrated anti-metastasis effect of RBL apart from its growth inhibitory effect. These results show the promising potential of RBL both as a diagnostic and therapeutic agent.

In silico and in vivo characterization of cabralealactone, solasodin and salvadorin in a rat model: potential anti-inflammatory agents

Background

The present study investigates the hepato- and DNA-protective effects of standardized extracts of Cleome brachycarpa (cabralealactone), Solanum incanum (solasodin), and Salvadora oleioides (salvadorin) in rats.

Materials and methods

Hepatotoxicity was induced with intraperitoneal injection of carbon tetrachloride (CCl₄) (1 mL/kg b.wt.) once a week for 12 weeks. The hepato- and DNA protective effects of the extracts in different combinations were compared with that of a standard drug Clavazin (200 mg/kg b.wt.). Tissue alanine aminotransferase, alpha-fetoprotein, tumor necrosis factor alpha (TNF-α), isoprostanes-2α, malondialdehyde, and 8-hydroxydeoxyguanosine, the significant hallmarks of oxidative stress, were studied.

Results

Histopathological findings of the liver sections from the rat group which received CCl₄+cabralealactone, solasodin, and salvadorin demonstrated improved centrilobular hepatocyte regeneration with moderate areas of congestion and infiltration comparable with Clavazin. For in silico study, the identified compounds were subjected to molecular docking with cyclooxygenase-2 and TNF-α followed by a molecular dynamics study, which indicated their potential as anti-inflammatory agents.

Conclusion

Cabralealactone, solasodin, and salvadorin confer some hepatoprotective and DNA-damage protective effects against CCl₄-induced toxicity. They successfully restored the normal architecture of hepatocytes and have the potential to be used as inhibitor to main culprits, that is, cyclooxygenase-2 and TNF-α. They can combat oxidative stress and liver injuries both as mono and combinational therapies. However, combination therapy has more ameliorating effects.

Clinical Assay for AFP-L3 by Using Multiple Reaction Monitoring-Mass Spectrometry for Diagnosing Hepatocellular Carcinoma

BACKGROUND

Lens culinaris agglutinin-reactive fraction of α-fetoprotein (AFP-L3) is a serum biomarker for hepatocellular carcinoma (HCC). AFP-L3 is typically measured by liquid-phase binding assay (LiBA). However, LiBA does not always reflect AFP-L3 concentrations because of its low analytical sensitivity. Thus, we aimed to develop an analytically sensitive multiple reaction monitoring-mass spectrometry (MRM-MS) assay to quantify AFP-L3 in serum.

METHODS

The assay entailed the addition of a stable isotope-labeled internal standard protein analog, the enrichment of AFP using a monoclonal antibody, the fractionation of AFP-L3 using L. culinaris agglutinin lectin, deglycosylation, trypsin digestion, online desalting, and MRM-MS analysis. The performance of the MRM-MS assay was compared with that of LiBA in 400 human serum samples (100 chronic hepatitis, 100 liver cirrhosis, and 200 HCC). Integrated multinational guidelines were followed to validate the assay for clinical implementation.

RESULTS

The lower limit of quantification of the MRM-MS assay (0.051 ng/mL) for AFP-L3 was less than that of LiBA (0.300 ng/mL). Thus, AFP-L3, which was not observed by LiBA in HCC samples (n = 39), was detected by the MRM-MS assay, improving the clinical value of AFP-L3 as a biomarker by switching to a more analytical sensitive platform. The method was validated, meeting all the criteria in integrated multinational guidelines.

CONCLUSIONS

Because of the lower incidence of false-negative findings, the MRM-MS assay is more suitable than LiBA for early detection of HCC.

Clinical outcome of hepatocellular carcinoma can be predicted by the expression of hepatic progenitor cell markers and serum tumour markers

The high heterogeneity of hepatocellular carcinomas (HCCs) complicates stratification of HCC patients for treatment. Therefore, it is necessary to establish a comprehensive panel of HCC biomarkers related to tumour behaviour and cancer prognosis. Resected HCCs from 251 patients were stained for hepatic progenitor cell (HPC) markers epithelial cell adhesion molecule (EpCAM), neural cell adhesion molecule (NCAM), delta-like 1 homolog (DLK1), and cytokeratin 19 (CK19). Staining patterns were analysed for their prognostic association with relapse-free survival and overall survival. α-Fetoprotein (AFP), lectin-reactive α-fetoprotein (AFP-L3), and des-γ-carboxy prothrombin (DCP) were assessed as indicators of HPC protein expression. Expression pattern of HPC markers correlated with tumour malignancy indicated by high AFP/AFP-L3 serum levels, more frequent vascular invasion, and poorer tumour differentiation. EpCAM expression, DCP ≥300 mAU/ml, age ≥60, and Child-Pugh score grade B or C were independent prognostic factors of poor outcome and were used in a new scoring system for HCC prognosis after operation. Expression of two or more HPC markers was a significant predictor of poor HCC outcome and serum levels of AFP/AFP-L3 correlated with the expression of HPC proteins. Our study paved the way for further elucidation of the association among HPC markers, serum tumour markers, and HCC clinical outcome for precision medicine.

Short O-GalNAc glycans: regulation and role in tumor development and clinical perspectives

BACKGROUND

While the underlying causes of cancer are genetic modifications, changes in cellular states mediate cancer development. Tumor cells display markedly changed glycosylation states, of which the O-GalNAc glycans called the Tn and TF antigens are particularly common. How these antigens get over-expressed is not clear. The expression levels of glycosylation enzymes fail to explain it.

SCOPE OF REVIEW

We describe the regulation of O-GalNAc glycosylation initiation and extension with emphasis on the initiating enzymes ppGalNAcTs (GALNTs), and introduce the GALA pathway--a change in GALNTs compartmentation within the secretory pathway that regulates Tn levels. We discuss the roles of O-GalNAc glycans and GALNTs in tumorigenic processes and finally consider diagnostic and therapeutic perspectives.

MAJOR CONCLUSIONS

Contrary to a common hypothesis, short O-glycans in tumors are not the result of an incomplete glycosylation process but rather reveal the activation of regulatory pathways. Surprisingly, high Tn levels reveal a major shift in the O-glycoproteome rather than a shortening of O-glycans. These changes are driven by membrane trafficking events.

GENERAL SIGNIFICANCE

Many attempts to use O-glycans for biomarker, antibody and therapeutic vaccine development have been made, but suffer limitations including poor sensitivity and/or specificity that may in part derive from lack of a mechanistic understanding. Deciphering how short O-GalNAc glycans are regulated would open new perspectives to exploit this biology for therapeutic usage. This article is part of a Special Issue entitled "Glycans in personalised medicine" Guest Editor: Professor Gordan Lauc.

Screening and detection of hepatocellular carcinoma

The increasing incidence of hepatocellular carcinoma (HCC) has led to the need to identify patients at risk for HCC so that a program of screening can be undertaken. Screening for HCC has led to earlier diagnosis of tumors and thus has aided in initiating optimal medical treatment earlier in the disease course. Advances in radiological techniques and the identification of more accurate serum tests to diagnose HCC continue to be important areas of study and exploration. In particular, there have been efforts to develop new tumor markers to aid in the diagnosis of HCC and guide therapy of tumors.

Elevated alpha-fetoprotein: differential diagnosis - hepatocellular carcinoma and other disorders

The incidence of cirrhosis-related hepatocellular carcinoma (HCC) is rising. Curative surgical options are available; outcomes are acceptable with early diagnosis. Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3) and des-gamma-carboxy prothrombin (DCP) are HCC risk markers. A high or increasing serum biomarker level can be predictive of the eventual development of HCC, large tumor size, advanced stage, extrahepatic metastases, portal vein thrombosis, and postoperative HCC recurrence. Based on FDA guidelines for HCC risk assessment, clinicians can consider using either the combination of AFP-L3 with DCP, or the combination of AFP-L3 with AFP and DCP.

Significant biomarkers for the management of hepatocellular carcinoma

Surveillance of hepatocellular carcinoma (HCC) is important for early detection. Imaging tests including computed tomography, magnetic resonance imaging and ultrasonography with or without various kinds of contrast medium are important options for detecting HCC. In addition to the imaging tests, various kinds of biomarkers including alpha-fetoprotein (AFP), lectin-bound AFP (AFP-L3) and protein induced by vitamin K absence or antagonist II (PIVKA-II) have been widely used to detect HCC and analyze treatment response. Recently, various kinds of novel biomarkers (proteins and miRNA) have been found to predict the malignancy potential of HCC and treatment response to specific therapies. Moreover, various combinations of well-established biomarkers and novel biomarkers have been tested to improve sensitivity and specificity. In practical terms, biomarkers that can be analyzed using peripheral blood samples might be more useful than immunohistochemical techniques. It has been reported that quantification of cytokines in peripheral blood and the analysis of peripheral immune subsets could be good biomarkers for managing HCC. Here, we describe the usefulness of and update well-established and novel biomarkers for the management of HCC.

Hepatocellular carcinoma tumour markers: current role and expectations

Tumour markers could be helpful along the continuum of care for patients with hepatocellular carcinoma; however, there is insufficient data for routine use of most current biomarkers in clinical practice. Therefore, the backbone of early detection, diagnosis and treatment response for hepatocellular carcinoma remains imaging-based. Alpha fetoprotein is the best studied of all biomarkers and may be of benefit for early detection when used in combination with ultrasound. Several other biomarkers, including AFP-L3, DCP, osteopontin, and GP73, are also being evaluated for early detection of hepatocellular carcinoma in phase III biomarker studies. Serum and tissue-based biomarkers and genomics may aid in HCC diagnosis, prognosis, and treatment selection; however, further studies are needed to better characterize their accuracy and potential role in clinical practice.

Evaluation of individual and combined applications of serum biomarkers for diagnosis of hepatocellular carcinoma: a meta-analysis

The clinical value of Serum alpha-fetoprotein (AFP) to detect early hepatocellular carcinoma (HCC) has been questioned due to its low sensitivity and specificity found in recent years. Other than AFP, several new serum biomarkers including the circulating AFP isoform AFP-L3, des-gamma-carboxy prothrombin (DCP) and Golgi protein-73 (GP73) have been identified as useful HCC markers. In this investigation, we review the current knowledge about these HCC-related biomarkers, and sum up the results of our meta-analysis on studies that have addressed the utility of these biomarkers in early detection and prognostic prediction of HCC. A systematic search in PubMed, Web of Science, and the Cochrane Library was performed for articles published in English from 1999 to 2012, focusing on serum biomarkers for HCC detection. Data on sensitivity and specificity of tests were extracted from 40 articles that met the inclusion criteria, and the summary receiver operating characteristic curve (sROC) was obtained. A meta-analysis was carried out in which the area under the curve (AUC) for each biomarker or biomarker combinations (AFP, DCP, GP73, AFP-L3, AFP + DCP, AFP + AFP-L3, and AFP + GP73) was used to compare the diagnostic accuracy of different biomarker tests. The AUC of AFP, DCP, GP73, AFP-L3, AFP + DCP, AFP + AFP-L3, and AFP + GP73 are 0.835, 0.797, 0.914, 0.710, 0.874, 0.748, and 0.932 respectively. A combination of AFP + GP73 is superior to AFP in detecting HCC and differentiating HCC patients from non-HCC patients, and may prove to be a useful marker in the diagnosis and screening of HCC. In addition, the AUC of GP73, AFP + DCP and AFP + GP73 are better than that of AFP. The clinical value of GP73, AFP + DCP, or AFP + GP73 as serological markers for HCC diagnosis needs to be addressed further in future studies.

Cell surface glycan alterations in epithelial mesenchymal transition process of Huh7 hepatocellular carcinoma cell

Background and Objective

Due to recurrence and metastasis, the mortality of Hepatocellular carcinoma (HCC) is high. It is well known that the epithelial mesenchymal transition (EMT) and glycan of cell surface glycoproteins play pivotal roles in tumor metastasis. The goal of this study was to identify HCC metastasis related differential glycan pattern and their enzymatic basis using a HGF induced EMT model.

Methodology

HGF was used to induce HCC EMT model. Lectin microarray was used to detect the expression of cell surface glycan and the difference was validated by lectin blot and fluorescence cell lectin-immunochemistry. The mRNA expression levels of glycotransferases were determined by qRT-PCR.

Results

After HGF treatment, the Huh7 cell lost epithelial characteristics and obtained mesenchymal markers. These changes demonstrated that HGF could induce a typical cell model of EMT. Lectin microarray analysis identified a decreased affinity in seven lectins ACL, BPL, JAC, MPL, PHA-E, SNA, and SBA to the glycan of cell surface glycoproteins. This implied that glycan containing T/Tn-antigen, NA2 and bisecting GlcNAc, Siaα2-6Gal/GalNAc, terminal α or βGalNAc structures were reduced. The binding ability of thirteen lectins, AAL, LCA, LTL, ConA, NML, NPL, DBA, HAL, PTL II, WFL, ECL, GSL II and PHA-L to glycan were elevated, and a definite indication that glycan containing terminal αFuc and ± Sia-Le, core fucose, α-man, gal-β(α) GalNAc, β1,6 GlcNAc branching and tetraantennary complex oligosaccharides structures were increased. These results were further validated by lectin blot and fluorescence cell lectin-immunochemistry. Furthermore, the mRNA expression level of Mgat3 decreased while that of Mgat5, FucT8 and β3GalT5 increased. Therefore, cell surface glycan alterations in the EMT process may coincide with the expression of glycosyltransferase.

Conclusions

The findings of this study systematically clarify the alterations of cell surface glycan in cancer EMT, and may provide novel insight for HCC metastasis.

Serum paraoxonase 1 heteroplasmon, a fucosylated, and sialylated glycoprotein in distinguishing early hepatocellular carcinoma from liver cirrhosis patients

Aberrant glycan structure of serum glycoproteins creates unique patterns in different stages of hepatocellular carcinoma (HCC), which provides potential glycan biomarkers for early diagnosis of HCC. In this study, tandem lectin affinity chromatography using aleuria aurantia lectin (AAL) and wheat germ agglutinin (WGA) was processed to purify both fucosylated and sialylated serum glycoproteins from 27 liver cirrhosis (LC) and 27 early HCC patients, in which 122 glycoproteins were finally screened out by liquid chromatography-tandem mass spectrometry (LC-MSMS). Among the 122 proteins identified by LC-MSMS, 8 of them were only identified in HCC serum and another 6 existed only in LC serum. Serum paraoxonase 1 (PON1) was immunoprecipitated from 47 individual patients and blotted by lectins, showing enhanced fucosylation and sialylation in HCC serum than those in LC serum. The area under the ROC curve (AUROC) for AAL-reactive PON1 was 0.892 with a sensitivity of 71.4% and a specificity of 94.7% in differentiating early HCC from LC. Similarly, WGA-reactive PON1 had an AUROC of 0.902 with a sensitivity of 95.2% and a specificity of 78.9%. The data indicated that the glycan differences of serum PON1 might serve as potential glycan biomarkers for distinguishing early HCC from LC patients.

Diagnosis of hepatocellular carcinoma: role of tumor markers and liver biopsy

Early diagnosis of hepatocellular carcinoma (HCC) has a significant impact on survival by implementation of effective treatment strategies, including hepatic resection, locoregional ablative therapy, and liver transplantation. The use of serum tumor markers and biopsy are particularly important for diagnosis of small hepatic lesions with atypical features on imaging studies. α-Fetoprotein remains the most frequently used tumor marker for the diagnosis of HCC. The development of novel serum biomarkers for HCC, identification of molecular markers for tissue immunohistochemistry, and emergence of new diagnostic techniques such as proteomic profiling may improve the early detection rate of HCC in the future.

Cancer biomarkers: are we ready for the prime time?

A biomarker is a characteristic that is objectively measured and evaluated as an indicator of normal biologic processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention. In cancer, a biomarker refers to a substance or process that is indicative of the presence of cancer in the body. A biomarker might be either a molecule secreted by a tumor or it can be a specific response of the body to the presence of cancer. Genetic, epigenetic, proteomic, glycomic, and imaging biomarkers can be used for cancer diagnosis, prognosis and epidemiology. These markers can be assayed in non-invasively collected biofluids. However, few cancer biomarkers are highly sensitive and specific for cancer detection at the present time. Consequently, biomarkers are not yet ready for routine use due to challenges in their clinical validation for early disease detection, diagnosis and monitoring to improve long-term survival of patients.

National Academy of Clinical Biochemistry Laboratory Medicine Practice Guidelines for use of tumor markers in liver, bladder, cervical, and gastric cancers

BACKGROUND

Updated National Academy of Clinical Biochemistry Laboratory Medicine Practice Guidelines for the use of tumor markers in the clinic have been developed.

METHODS

Published reports relevant to use of tumor markers for 4 cancer sites--liver, bladder, cervical, and gastric--were critically reviewed.

RESULTS

Alpha-fetoprotein (AFP) may be used in conjunction with abdominal ultrasound for early detection of hepatocellular carcinoma (HCC) in patients with chronic hepatitis or cirrhosis associated with hepatitis B or C virus infection. AFP concentrations >200 microg/L in cirrhotic patients with typical hypervascular lesions >2 cm in size are consistent with HCC. After a diagnosis of HCC, posttreatment monitoring with AFP is recommended as an adjunct to imaging, especially in the absence of measurable disease. Although several urine markers have been proposed for bladder cancer, none at present can replace routine cystoscopy and cytology in the management of patients with this malignancy. Some may, however, be used as complementary adjuncts to direct more effective use of clinical procedures. Although carcinoembryonic antigen and CA 19-9 have been proposed for use gastric cancer and squamous cell carcinoma antigen for use in cervical cancer, none of these markers can currently be recommended for routine clinical use.

CONCLUSIONS

Implementation of these recommendations should encourage optimal use of tumor markers for patients with liver, bladder, cervical, or gastric cancers.

Role of alpha-fetoprotein in hepatocellular carcinoma: prognostication, treatment monitoring or both?

Despite recent breakthroughs in the treatment for both early and advanced hepatocellular carcinoma, the development of markers for prognostication and treatment monitoring remains to be explored. Serum alpha-fetoprotein has been frequently measured at diagnosis and serially during treatment by clinicians for decades, with an aim for prognostication of disease and monitoring of treatment response. In this review, the evidence regarding the prognostic value of serum alpha-fetoprotein and the value of serial alpha-fetoprotein in the monitoring of treatment efficacy will be discussed, with emphasis on recent data.

Alpha-fetoprotein, des-gamma carboxyprothrombin, and lectin-bound alpha-fetoprotein in early hepatocellular carcinoma

BACKGROUND & AIMS

Alpha-fetoprotein (AFP) is widely used as a surveillance test for hepatocellular carcinoma (HCC) among patients with cirrhosis. Des-gamma carboxy-prothrombin (DCP) and lectin-bound AFP (AFP-L3%) are potential surveillance tests for HCC. The aims of this study were to determine performance of DCP and AFP-L3% for the diagnosis of early HCC; whether they complement AFP; and what factors affect DCP, AFP-L3%, or AFP levels.

METHODS

We conducted a large phase 2 biomarker case-control study in 7 academic medical centers in the United States. Controls were patients with compensated cirrhosis and cases were patients with HCC. AFP, DCP, and AFP-L3% levels were measured blinded to clinical data in a central reference laboratory.

RESULTS

A total of 836 patients were enrolled: 417 (50%) were cirrhosis controls and 419 (50%) were HCC cases, of which 208 (49.6%) had early stage HCC (n = 77 very early, n = 131 early). AFP had the best area under the receiver operating characteristic curve (0.80, 95% confidence interval [CI]: 0.77-0.84), followed by DCP (0.72, 95% CI: 0.68-0.77) and AFP-L3% (0.66, 95% CI: 0.62-0.70) for early stage HCC. The optimal AFP cutoff value was 10.9 ng/mL leading to a sensitivity of 66%. When only those with very early HCC were evaluated, the area under the receiver operating characteristic curve for AFP was 0.78 (95% CI: 0.72-0.85) leading to a sensitivity of 65% at the same cutoff.

CONCLUSIONS

AFP was more sensitive than DCP and AFP-L3% for the diagnosis of early and very early stage HCC at a new cutoff of 10.9 ng/mL.

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.

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.

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.

AFP-L3 in chronic liver diseases with persistent elevation of alpha-fetoprotein

BACKGROUND

Alpha-fetoprotein (AFP) is an important marker for hepatocellular carcinoma (HCC). However, persistent elevation of AFP is found in patients with chronic liver diseases. The value of AFP-L3, which is more specific than AFP, was examined in such patients.

METHODS

We enrolled patients without image-detectable tumor, but with transient AFP value > 900 ng/mL (group A) or with persistent AFP value > 50 ng/mL for longer than 6 months (group B). Forty-one patients with HCC and AFP value > 50 ng/mL were included as the HCC control group (group C). AFP-L3 measurement was done by lectin-affinity electrophoresis coupled with antibody-affinity blotting. The study patients were followed with AFP, liver biochemistry and abdominal ultrasound at 3- to 6-month intervals. Additional studies were done when a tumor was suspected.

RESULTS

One of 17 patients in group A and 13 of 39 patients in group B developed HCC within 2 years. When the cutoff value of AFP-L3 ratio was 15%, both the sensitivity and specificity were 71% for prediction of HCC during the next 2 years in all patients. Ninety percent of tumors larger than 5 cm had AFP-L3 > 15%, compared with only 60% for tumors smaller than 2 cm. Three patients in group A had AFP-L3 ratio > 17.5%. One patient developed HCC 10 months later; the other 2 patients were associated with hepatic failure.

CONCLUSION

AFP-L3 provides a clue in HCC detection in patients with persistent elevation of AFP. However, AFP-L3 could be highly elevated in severe hepatitis.

The predictive ability of serum α-fetoprotein for hepatocellular carcinoma is linked with the characteristics of the target population at surveillance

BACKGROUND

Serum alpha-fetoprotein (AFP) is the most important tumor marker for hepatocellular carcinoma (HCC). The reported predictive accuracy of AFP for HCC widely varied. This study investigated the factors contributory to the heterogeneity of the ability of AFP to detect HCC.

METHODS

A total of 1,135 patients were categorized into four groups: HCC undergoing surgical resection (n = 248), chronic hepatitis B (CHB, n = 413), chronic hepatitis C (CHC, n = 207), and liver cirrhosis (LC, n = 267). The area under the receiver operating characteristic curve (AUC) was estimated in different combinations.

RESULTS

The AUC was the highest when HCC patients were co-analyzed with patients with LC (0.805), followed by co-analyzing patients with CHB (0.797) and CHC (0.740). The optimal cutoffs for AFP were between 26 and 32 ng/ml. Patients with tumor size </=3 cm had a lower positive predictive value (PPV, 30%) compared to patients with tumor size >3 cm (46%), and HBsAg-negative and anti-HCV-positive patients had the lowest PPV (38%) compared to other groups (60%, 100%, and 82%) at a cutoff at 20 ng/ml. The AUC was lower for hepatitis B-negative subjects (0.684 and 0.509), compared to hepatitis B-positive subjects (0.826 and 0.806) stratified by the status of HCV. Elevated ALT >80 U/L and HCC independently predicted increased (>20 ng/ml) AFP levels.

CONCLUSIONS

Serum AFP had a fairly stable predictive accuracy for HCC, with an optimal cutoff around 30 ng/ml. ALT level, viral status, and tumor size may significantly confound its ability to detect HCC.

Evaluation of interleukin-6, interleukin-10 and human hepatocyte growth factor as tumor markers for hepatocellular carcinoma

AIM

Serum alpha-fetoprotein (AFP) is the most important tumor marker for hepatocellular carcinoma (HCC). Previous reports indicated that HCC was also associated with increased levels of interleukin (IL)-6, IL-10 and hepatocyte growth factor (HGF). This study investigated the role of these cytokines as tumor markers for HCC.

METHOD

A total of 128 adults were prospectively enrolled and categorized into four groups: normal subjects (n=29), chronic hepatitis B or C (n=50), non-HCC tumors (n=23) and HCC (n=26). Serum AFP, IL-6, IL-10 and HGF levels were determined in all subjects.

RESULTS

The expression of IL-6 or IL-10 (> or =3 pg/ml), or high level of HGF (>1000 pg/ml) or AFP (>20 ng/ml) was observed in only 0-3% of normal subjects. Patients with HCC more frequently had higher IL-6 and IL-10 levels (p<0.05), whereas HGF levels in HCC patients were not significantly elevated compared to patients with chronic hepatitis or non-HCC tumors. Among patients with low (<20 ng/ml) AFP level, IL-6 or IL-10 expression was significantly associated with the existence of HCC (p<0.05). Patients with large (>5 cm) HCC more often had increased IL-6, IL-10 or AFP levels (p values all <0.05).

CONCLUSIONS

Serum levels of IL-6 and IL-10 are frequently elevated in patients with HCC but not in benign liver disease or non-HCC tumors. IL-6 and IL-10 may help identify a subset of HCC patients with low AFP level, and may serve as complementary tumor markers in these patients.

New frontiers in biomarkers for hepatocellular carcinoma

Hepatocellular carcinoma represents the fifth most frequent cancer in the world; it commonly occurs on cirrhotic liver. Prognosis and survival are still poor, mainly because of diagnosis at a late stage and/or recurrence of the disease. For this reason, surveillance strategies are widely used to screen for early occurrence of cancer in populations at risk. Alpha-foetoprotein is so far the only serological marker available, but its diagnostic accuracy is unsatisfactory because of low sensitivity despite reliable specificity. For this reason, new biomarkers for the diagnosis of hepatocellular carcinoma are in strong demand by clinicians. In this review, we will focus on new biomarkers currently under investigation, but also on still newer, very promising biomarkers that seem to significantly improve diagnosis.

Screening tests for hepatocellular carcinoma

The incidence of hepatocellular carcinoma (HCC) is rising throughout the world. HCC meets the criteria for which a disease benefits from screening or surveillance: it is an important health problem; those with cirrhosis are the targets for surveillance; there is acceptable treatment if diagnosed early; surveillance using alpha-fetoprotein and ultrasound has been shown to be cost effective; surveillance is widely implemented by health care professionals and accepted by patients; standardized recall procedures exists; and the screening tests must achieve an acceptable level of accuracy in the population undergoing screening. The latter point is the main limitation of surveillance for HCC. In this review we will discuss the currently available tests for the surveillance of HCC.

Newer markers for hepatocellular carcinoma

The incidence of hepatocellular carcinoma (HCC) is increasing worldwide; the overall survival of patients with HCC is grim because most patients are diagnosed late, when curative treatment is not possible. Cirrhosis is the strongest risk factor for the development of HCC. HCC surveillance with alpha-fetoprotein (AFP) and ultrasonography has been recommended for persons with cirrhosis. However, AFP level is insensitive for the early detection of HCC, and ultrasonography is expensive and operator dependent. Clearly, there is a need for novel strategies for the early detection of HCC. The ideal biomarker assay for HCC would be sensitive, specific, noninvasive, reproducible, inexpensive, and acceptable to patients. The Early Detection Research Network of the National Cancer Institute has proposed 5 phases for biomarker validation: preclinical exploratory studies, clinical assay development for disease, retrospective longitudinal study to detect preclinical disease, prospective screening study, and cancer control studies. Several biomarkers, such as des-gamma carboxyprothrombin, lens culinaris agglutinin-reactive AFP, human hepatocyte growth factor, and insulin-like growth factor-1, are promising, but none of these markers has been validated for clinical use. Limitations of the current literature include inadequate sample size, heterogeneity in biomarker assay methods and result reporting, limited analysis of demographics and cause of liver disease as covariates in the expression of these markers, and a scarcity of longitudinal studies evaluating the ability of biomarkers to detect preclinical disease. There is an urgent need for novel biomarkers for the detection of early HCC; the National Cancer Institute proposal provides a framework for future validation studies.

Screening and treatment for hepatocellular carcinoma

Surveillance for hepatocellular carcinoma (HCC) has become routine despite a lack of evidence of efficacy. Suitable candidates for surveillance include patients with cirrhosis and some subsets of noncirrhotic chronic hepatitis B carriers. The best surveillance testis ultrasonography at 6- to 12-month intervals. Serological tests are less effective. Defining an abnormal result is difficult in the cirrhotic liver. Diagnosis requires radiological investigations and may require a biopsy if the lesion is between 1 and 2 cm in diameter. In the face of an abnormal surveillance test and failure to confirm the diagnosis initially, enhanced follow-up is required. HCC can be treated for cure by liver transplantation, resection, or local ablation. For patients with suitable lesions, liver transplantation offers the best form of therapy. Chemoembolization offers increased survival over no therapy. Several experimental therapies are being investigated.

Pathogenesis and screening for hepatocellular carcinoma

Hepatocellular carcinoma is an increasingly common clinical problem. Investigators have begun to understand aspects of the pathogenesis of the tumor, mainly from a morphologic point of view. Preneoplastic lesions and early cancer may be difficult to distinguish radiologically. Nonetheless, programs for surveillance of liver cancer have been developed. Little uniformity exists in methods of surveillance, and even less in methods of investigation and follow-up after an abnormal result is obtained. This article attempts to bring some rigor to the understanding of hepatocellular carcinoma.

Lens culinaris agglutinin-reactive alpha-fetoprotein as a prognostic marker in patients with hepatocellular carcinoma undergoing transcatheter arterial chemoembolization

Lens culinaris agglutinin-reactive alpha-fetoprotein (AFP-L3) is known to be a useful marker for the diagnosis of hepatocellular carcinoma (HCC). Recent studies have shown that positive AFP-L3 results after treatment predicts tumor recurrence and poor clinical outcome. This study was to evaluate the role of pretreatment AFP-L3 as a prognostic marker for response to transcatheter arterial chemoembolization (TACE) and survival in patients with HCC. Forty-six patients with HCC who underwent TACE were analyzed. Agglutinin-reactive AFP was measured by lectin-affinity electrophoresis coupled with antibody-affinity blotting. Agglutinin-reactive AFP results larger than 24.4% were considered to be positive. Agglutinin-reactive AFP fractions were positive in 32 patients. Agglutinin-reactive AFP-positive patients had poorer performance status, larger tumors, frequent portal vein thrombosis, and higher levels of serum AFP. The partial response rate to TACE was lower in AFP-L3-positive patients than in AFP-L3-negative ones (37.5% vs. 78.6%, p = 0.01). Tumor size and AFP-L3 were two independent predictive factors for response to TACE. The 2-year survival rate was lower in AFP-L3-positive patients than in AFP-L3-negative ones (21.2% vs. 78.6%, p = 0.01). Child-Pugh class, AFP-L3, the presence of portal vein thrombosis, and response to TACE were independent prognostic factors for survival. In conclusion, pretreatment status of AFP-L3 could be considered a useful marker for predicting clinical outcome in patients with HCC who underwent TACE.

Clinical utility of Lens culinaris agglutinin-reactive alpha-fetoprotein in small hepatocellular carcinoma: special reference to imaging diagnosis

BACKGROUND/AIMS

Blood concentration levels of alpha-fetoprotein like the Lens culinaris agglutinin-reactive fraction (AFP-L3) are a useful marker for predicting the long-term prognosis of hepatocellular carcinoma. This study investigated the relationship between serum AFP-L3 and various imaging modalities.

METHODS

Sixty-three patients with small hepatocellular carcinomas < or = 2 cm in diameter were studied. Serum AFP-L3 concentrations were measured by lectin-affinity electrophoresis coupled with antibody-affinity blotting and expressed as % AFP-L3 (the percent of AFP-L3 as total AFP). A clinical "cutoff level" of 10% was used in this study to indicate the presence of hepatocellular carcinoma. Selective hepatic intraarterial digital subtraction angiography (DSA), ultrasonographic angiography with carbon dioxide microbubbles (USAG), and computed tomography during arterial portography (CTAP) were performed to evaluate the hemodynamics of hepatic nodules.

RESULTS

Fourteen (22.2%) of the 63 patients were positive for % AFP-L3. The % AFP-L3 levels (n=45, 4.4%) of patients with hypervascular tumors were significantly higher than those (n=15, 0.0%) of patients with isovascular or hypovascular tumors as determined by USAG (p=0.0061). The % AFP-L3 levels (n=53, 4.4%) of patients with a negative portal blood supply were significantly higher than the % AFP-L3 levels (n=7, 0.0%) of patients with a positive portal blood supply as determined by CTAP (p=0.0140). The % AFP-L3 levels of patients with tumors with a long doubling time (DT) were significantly lower than for patients with tumors with a short DT (p=0.0176).

CONCLUSION

AFP-L3 is a positive indicator which may be more specific for small advanced hepatocellular carcinoma.

The fucosylation index of alpha-fetoprotein as a possible prognostic indicator for patients with hepatocellular carcinoma

BACKGROUND

The aim of this study was to elucidate the usefulness of measuring the fucosylation index (FI) of alpha-fetoprotein (AFP) before the initiation of therapy as a new prognostic indicator for patients with hepatocellular carcinoma (HCC).

METHODS

One hundred twelve patients with HCC who underwent transcatheter arterial embolization, chemoembolization, and/or percutaneous ethanol injection were examined in the current study. FI was determined by crossed immunoaffino-electrophoresis in the presence of Lens culinaris agglutinin.

RESULTS

When the tentative discriminating value of FI was set at 18%, the mean survival rate for the group whose FI was higher than 18% was significantly lower than that for the group whose FI was equal to or less than 18%, according to the generalized Wilcoxon test (P = 0.0117) and the log rank test (P = 0.0183). The survival rate for HCC patients with AFP concentrations of more than 200 ng/mL was also significantly lower than that for patients with AFP in the range of 21-200 ng/mL, according to the generalized Wilcoxon test (P = 0.0017) and the log rank test (P = 0.0018). When FI was combined with AFP concentration, a highly significant difference was observed between the group with FI >18% and AFP >200 ng/mL and another group with FI < or =18% and AFP < or =200 ng/mL, as determined by the generalized Wilcoxon test (P < 0.0001) and the log rank test (P = 0.0003). An analysis of multiple covariates in the prognostic factors with the Cox proportional hazards model showed that FI was one of the independent prognostic factors.

CONCLUSIONS

The current study indicates that measuring FI from sera before the initiation of treatment serves as a new prognostic factor and may improve prognostic estimates and appraisal of therapeutic outcomes for patients with HCC.

Clinical evaluation of pancreatitis-associated protein as a serum marker of hepatocellular carcinoma: comparison with alpha-fetoprotein

This study evaluated the significance of serum pancreatitis-associated protein (PAP) assay, as a marker of hepatocellular carcinoma (HCC), in comparison and combined with alpha-fetoprotein (AFP) assay. Sixty-five patients with HCC, 59 with liver cirrhosis (LC) and 68 asymptomatic controls (C) were studied. PAP and AFP values significantly increased from C to LC and HCC group (p < 0.0001). The area under receiver-operating characteristic (ROC) curve for the two markers was not statistically different. At 100% specificity, ROC analysis gave a cut-off level for AFP of 166 IU/l with 40% sensitivity, and a cut-off level of 240 microg/l for PAP with 23% sensitivity. Diagnostic accuracy of combined AFP and PAP assay was significantly higher than AFP alone. Sensitivity according to tumor size also improved using the combined assay, especially for tumors <5 cm. Stepwise logistic regression indicated that AFP, but not PAP, was associated with an increased risk of developing HCC. These data confirm that PAP production is increased only in some cases of HCC and that the combined PAP and AFP assays do not significantly improve specificity over AFP assay alone. Consequently, PAP assay can only be recommended in cases of justified suspicion of HCC with negative AFP.