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

Enhanced activation of memory, but not naïve, B cells in chronic hepatitis C virus-infected patients with cryoglobulinemia and advanced liver fibrosis

Mixed cryoglobulinemia is the most common extrahepatic disease manifestation of chronic hepatitis C virus (HCV) infection, where immunoglobulins precipitate at low temperatures and cause symptoms such as vasculitis, glomerulonephritis and arthralgia. HCV-associated cryoglobulinemia is also strongly linked with the development of B cell non-Hodgkin lymphoma. Abnormal B cell function in HCV infections can lead to the formation of HCV cryoglobulin complexes that usually comprise monoclonal rheumatoid factor and HCV-specific immune complexes. The aim of this study was to characterize the activation phenotype of B cells from patients with chronic HCV infection in comparison to healthy controls using flow cytometry. In addition, we determined how the activation status varies depending on the presence of cryoglobulinemia and advanced liver fibrosis. We found that only memory B cells, not naïve cells, were significantly activated in chronic HCV infection when compared with healthy controls. We also identified markers of memory B cell activation that were specific for HCV patients with cryoglobulinemia (CD86, CD71, HLA-DR) and advanced liver disease (CD86). Our results demonstrate that HCV infection has differential effects on B cells depending on the severity of hepatic and extrahepatic disease.

Presence of EpCAM-positive circulating tumor cells as biomarker for systemic disease strongly correlates to survival in patients with hepatocellular carcinoma

Current imaging technologies do not sufficiently detect micrometastasis and therefore do not allow adequate stratification of patients with hepatocellular carcinoma (HCC) for curative or systemic therapy. In HCC, presence of stem cell-like, epithelial cell adhesion molecule (EpCAM)-positive cells correlates with tumor aggressiveness and formation of metastasis. Therefore, we investigated the prognostic relevance of EpCAM-positive circulating tumor cells (CTCs) in patients with HCC. Blood from 78 patients (19 patients in the control cohort and 59 patients with HCC) was tested for CTCs with the CellSearch™ system. Correlation analysis to overall survival (OS), the Barcelona Clinic Liver Cancer (BCLC) staging system, macroscopic and microscopic vascular invasion and alpha-fetoprotein (AFP) levels were performed. We detected ≥1 CTC in 18/59 HCC patients and in 1/19 patients with cirrhosis or benign hepatic tumor (p = 0.026). OS was significantly shorter (460 vs. 746 days) in the CTC-positive cohort (p = 0.017). Comparing BCLC stages, significant differences in CTC detection rates were also observed: BCLC stages A 1/9, B 6/31 and C 11/19 (p = 0.006). Ten of 18 patients with macroscopic and 10/16 patients with microscopic vascular invasion exhibited positive findings in CTC testing (p = 0.004 and p = 0.006). Furthermore, CTC results correlated to AFP (cutoff > 400 ng/mL) levels (p = 0.050). Our study demonstrates frequent presence of EpCAM-positive CTC in patients with intermediate or advanced HCC and its prognostic value for OS with possible implications for future treatment stratification.

The assessment of data mining for the prediction of therapeutic outcome in 3719 Egyptian patients with chronic hepatitis C

INTRODUCTION

Decision-tree analysis; a core component of data mining analysis can build predictive models for the therapeutic outcome to antiviral therapy in chronic hepatitis C virus (HCV) patients.

AIM

To develop a prediction model for the end virological response (ETR) to pegylated interferon PEG-IFN plus ribavirin (RBV) therapy in chronic HCV patients using routine clinical, laboratory, and histopathological data.

PATIENTS AND METHODS

Retrospective initial data (19 attributes) from 3719 Egyptian patients with chronic HCV presumably genotype-4 was assigned to model building using the J48 decision tree-inducing algorithm (Weka implementation of C4.5). All patients received PEG-IFN plus RBV at Cairo-Fatemia Hospital, Cairo, Egypt in the context of the national treatment program. Factors predictive of ETR were explored and patients were classified into seven subgroups according to the different rates of ETR. The universality of the decision-tree model was subjected to a 10-fold cross-internal validation in addition to external validation using an independent dataset collected of 200 chronic HCV patients.

RESULTS

At week 48, overall ETR was 54% according to intention to treat protocol. The decision-tree model included AFP level (<8.08 ng/ml) which was associated with high probability of ETR (73%) followed by stages of fibrosis and Hb levels according to the patients' gender followed by the age of patients.

CONCLUSION

In a decision-tree model for the prediction for antiviral therapy in chronic HCV patients, AFP level was the initial split variable at a cutoff of 8.08 ng/ml. This model could represent a potential tool to identify patients' likelihood of response among difficult-to-treat presumably genotype-4 chronic HCV patients and could support clinical decisions regarding the proper selection of patients for therapy without imposing any additional costs.

Glycoproteomic analysis of tissues from patients with colon cancer using lectin microarrays and nanoLC-MS/MS

The current study evaluated the glycoproteomic profile of tissues from colon cancer patients. The lectin microarray was first performed to compare the glycoprotein profiles between colon cancer and matched normal tissues. Level of N-acetylglucosamine (GlcNAc) that Solanum tuberosum lectin (STL) bound was found to be elevated in colon cancer, which was verified through lectin histochemistry. The subsequent glycoproteomic analysis based on STL enrichment of glycoproteins followed by label-free quantitative nano liquid chromatography-mass spectrometry/mass spectrometry (nanoLC-MS/MS) analysis identified 72 proteins in high confidence. Among these proteins, 17 were exclusively detected in cancer tissues, and 14 were significantly upregulated in tumor tissues. Annexin A1 and HSP90β were chosen for further investigation by immunoprecipitation coupled with lectin blots, western blots and tissue microarrays. Both Annexin A1 and HSP90β were GlcNAcylated, and their protein expressions were elevated in colon cancer, compared to normal tissues. Moreover, specific changes of GlcNAc abundances in Annexin A1 and HSP90β suggested that tumor-specific glycan patterns could serve as candidate biomarkers of colon cancer for distinguishing cancer patients from healthy individuals.

Des-gamma-carboxy prothrombin identified by P-11 and P-16 antibodies reflects prognosis for patients with hepatocellular carcinoma

BACKGROUND AND AIMS

Serum des-γ-carboxy prothrombin (DCP) is an established tumor marker in patients with hepatocellular carcinoma (HCC), which can be identified by using MU-3 antibody. The MU-3 antibody mainly reacts with the 9-10 glutamic acid residues of DCP (conventional DCP). Since other variants of DCP with fewer glutamic acid residues can be detected using P-11 and P-16 antibodies (code name: NX-PVKA), we examined the clinical characteristics associated with NX-PVKA, and whether NX-PVKA is a useful measure in HCC patients.

METHODS

Participants comprised 197 HCC patients admitted to our hospital between 2001 and 2010. NX-PVKA, conventional DCP, alpha-fetoprotein, and L3 fraction of alpha-fetoprotein were measured prior to initiation of HCC treatment.

RESULTS

Of the tumor markers assessed, NX-PVKA was the only significant predictor of prognosis (hazard ratio, 81.32; P < 0.0001). Patients with NX-PVKA level ≥ 100 mAU/mL showed significantly lower survival rates (P < 0.0001). NX-PVKA level was also significantly associated with platelet count, prothrombin time, C-reactive protein, sex, maximum tumor size, number of nodules, and portal venous invasion by HCC. Finally, using NX-PVKA level and other clinical parameters, we established a prognostic model to estimate patient survival time.

CONCLUSIONS

NX-PVKA offers the best marker of tumor prognosis among HCC patients, and is strongly associated with tumor factors and hepatic functional reserve. NX-PVKA could be useful for clinical evaluation of tumor severity, as well as the estimated duration of survival among patients with HCC.

Kinetic-exclusion analysis-based immunosensors versus enzyme-linked immunosorbent assays for measurement of cancer markers in biological specimens

Kinetic exclusion analysis (KinExA)-based immunosensors and enzyme-linked immunosorbent assays (ELISA) have been developed and validated for measurement of five different cancer markers in biological specimens. These markers were: 2'-deoxycytidine (dCyd), 8-hydroxy-2'-deoxyguanosine (8HdG), carbohydrate antigen (CA15-3), α-fetoprotein (AFP), and β-subunit of human chorionic gonadotropin (β-HCG). The KinExA-based assays were conducted on the KinExA™ 3200 instrument. The ELISA assays employed the competitive immunoassay format for dCyd and 8HdG, however they employed the direct sandwich-type format for CA15-3, AFP, and β-HCG. Each assay was validated in terms of its limit of detection, working range, precision profile, and accuracy. The analytical performances of the KinExA-based sensors were found to be superior to the ELISA for the five markers. The data demonstrated that the format of the assay may influence its performance characteristics (sensitivity, precision, etc.), even when exactly the same reagents are employed. The superior performance of the KinExA format is most likely due to: (1) the high surface area of beads containing the immobilized capture in the flow cell of the instrument, (2) the high flow rate of the reagents passing through the beads, which minimizes the diffusion limitations at the reaction surface, and (3) the limited time that the antibody is in contact with the capture reagent. The KinExA-based assays exhibited three noteworthy properties compared with ELISA: (1) avoiding the problems of mass transport limitations, and mobility effects, (2) KinExA analysis with automated sampling increase the assay convenience; and (3) providing high sensitivity with a lower limit of detection and better precision than ELISA. The proposed KinExA-based immunosensors are anticipated to have a great value in measurement of the cancer markers where more confident results are needed.

Aberrant PSA glycosylation--a sweet predictor of prostate cancer

Prostate cancer--the most commonly diagnosed cancer in men worldwide--can have a substantial effect on quality of life, regardless of the route the cancer takes. The serum PSA assay is the current gold standard option for diagnosing prostate cancer. However, a growing body of evidence suggests that PSA screening for prostate cancer results in extensive overdiagnosis and overtreatment. It is increasingly evident that the potential harm from overdiagnosis (in terms of unnecessary biopsies) must be weighed against the benefit derived from the early detection and treatment of potentially fatal prostate cancers. Rapid screening methods have been used to analyse glycosylation patterns on glycoproteins in large cohorts of patients, enabling the identification of a new generation of disease biomarkers. Changes to the expression status of certain glycan structures are now widely thought to be common features of tumour progression. In light of this development, much research has focused on the potential role of altered PSA glycosylation patterns in discriminating between significant and insignificant prostate cancers, with the aim of developing a more reliable diagnostic tool than the current serum PSA test.

Altered of apoptotic markers of both extrinsic and intrinsic pathways induced by hepatitis C virus infection in peripheral blood mononuclear cells

Background

Chronic hepatitis C (CHC) has emerged as a leading cause of cirrhosis in the U.S. and across the world. To understand the role of apoptotic pathways in hepatitis C virus (HCV) infection, we studied the mRNA and protein expression patterns of apoptosis-related genes in peripheral blood mononuclear cells (PBMC) obtained from patients with HCV infection.

Methods

The present study included 50 subjects which plasma samples were positive for HCV, but negative for human immunodeficiency virus (HIV) or hepatitis B virus (HBV). These cases were divided into four groups according to METAVIR, a score-based analysis which helps to interpret a liver biopsy according to the degree of inflammation and fibrosis. mRNA expression of the studied genes were analyzed by reverse transcription of quantitative polymerase chain reaction (RT-qPCR) and protein levels, analyzed by ELISA, was also conducted. HCV genotyping was also determined.

Results

HCV infection increased mRNA expression and protein synthesis of caspase 8 in group 1 by 3 fold and 4 fold, respectively (p < 0.05). In group 4 HCV infection increased mRNA expression and protein synthesis of caspase 9 by 2 fold and 1,5 fold, respectively (p < 0.05). Also, caspase 3 mRNA expression and protein synthesis had level augumented by HCV infection in group 1 by 4 fold and 5 fold, respectively, and in group 4 by 6 fold and 7 fold, respectively (p < 0.05).

Conclusions

HCV induces alteration at both genomic and protein levels of apoptosis markers involved with extrinsic and intrinsic pathways.

Changes of serum alpha-fetoprotein and alpha-fetoprotein-L3 after hepatectomy for hepatocellular carcinoma: prognostic significance

BACKGROUND

Alpha-fetoprotein (AFP) is the most established tumor marker of hepatocellular carcinoma (HCC), but one of its limitations is non-specificity. Many studies have demonstrated that alpha-fetoprotein-L3 (AFP-L3) is more specific than AFP in the early diagnosis and prognosis of HCC. However, there is a lack of knowledge about the post-hepatectomy profiles of serum AFP and AFP-L3 values in HCC patients. To identify the profiles after surgical resection of HCC, we analyzed the correlation between the profiles and postoperative HCC recurrence or survival, and evaluated their utility in predicting postoperative therapeutic efficacy and prognosis.

METHODS

From August 2003 to December 2004, 318 patients with positive serum AFP who had received surgical resections were enrolled in this study. Preoperative and postoperative serum AFP and AFP-L3 levels were measured simultaneously and regularly, and their postoperative profiles during a long-term follow-up were recorded and summarized.

RESULTS

A high ratio of AFP-L3 to total AFP was shown to correlate with pathologic features of aggressiveness. The overall 1-, 3-, and 5-year recurrence rates of the whole series were 28%, 57%, and 84%, and the overall survival rates were 86%, 61%, and 33%, respectively. The changes of serum AFP and AFP-L3 after hepatectomy for HCC were classified into 3 groups (group A: AFP-L3 undetectable; group B: AFP-L3 <10%; and group C: AFP-L3 >10%). Patients with positive postoperative AFP-L3 had significantly earlier recurrence than those with negative results. The overall survival was significantly shorter in the positive groups than in the groups negative for postoperative AFP-L3.

CONCLUSION

Post-hepatectomy changes in serum AFP and AFP-L3 levels occurred in three distinct patterns, which were closely correlated with HCC recurrence and patient survival with different prognostic values.

The EIIAPA chimeric promoter for tumor specific gene therapy of hepatoma

PURPOSE

For targeted imaging and therapy of hepatocellular carcinoma (HCC), we established a chimeric promoter (EIIAPA) containing alpha-fetoprotein (AFP) promoter and hepatitis B virus enhancer II (EIIA) to control downstream expression of reporter and therapeutic genes.

PROCEDURES

We combined AFP promoter and EIIA to establish a chimeric EIIAPA promoter, then developed a bi-cistronic plasmid vector containing HSV1-tk and luciferase genes controlled by EIIAPA to stably transfect HCC cells. The selective transcriptional activity of EIIAPA was assayed by bioluminescence imaging (BLI) and the function of EIIAPA was determined by in vivo microPET and BLI.

RESULTS

The luciferase expression driven by EIIAPA was higher than that driven by AFP promoter in HCC cell lines. EIIAPA-tk induced cytotoxicity was observed only in HepG2 cells. Accumulation of ¹³¹I-FIAU and bioluminescent signal were detected on HepG2 tumors but not in parental tumors. The HepG2 tumors derived from lentiviral-transduced EIIAPA-tk expressing cells accumulated ¹²⁴I-FIAU whereas the ARO tumors did not. The transfected HepG2 tumors expressed adequate EIIAPA-controlled HSV1-TK and the tumor regressed after ganciclovir treatment.

CONCLUSION

The chimeric EIIAPA is a potential candidate promoter for targeted imaging and gene therapy of HCC.

Surveillance for hepatocellular carcinoma

The only hope for a cure from hepatocellular carcinoma (HCC) rests on early diagnosis as it can be attained through semiannual surveillance with abdominal ultrasound (US) of patients at risk. While the strategy of semiannual screening rests on the growth rate of the tumor that in cirrhotic patients takes 6 months to double its volume, on average, the noninvasive radiological diagnosis of HCC is possible in cirrhotic patients with a de novo HCC and patients with chronic hepatitis B. More recently, metabolic diseases related to insulin resistance, including diabetes and obesity, have been recognized to be causally related to HCC as well, in most patients bridging HCC to the histopathological diagnosis of non-alcoholic steatohepatitis (NASH). While the endpoint of an early diagnosis is achieved quite easily in most patients with >1 cm HCC by computed tomography (CT) or magnetic resonance imaging (MRI) demonstrating the specific pattern of an intense contrast uptake during the arterial phase (wash-in) and contrast wash-out during the venous/delayed phase, nodules <1 cm in size are more difficult to diagnose, almost invariably requiring an enhanced follow up with three monthly examinations with US until they grow in size or change their echo pattern. Owing to the lack of robust controlled evidence demonstrating a clinical benefit of surveillance, the real support for screening for liver cancer comes from the striking differences in response to therapy between screened populations in whom HCC is diagnosed and treated at early stages and patients with more advanced, incidentally detected tumors. This notwithstanding, numerous barriers work against screening effectiveness, including limited or outdated knowledge, lack of financial incentives, and limited access to appropriate testing and treatment. Though strengthening prediction in individual patients is expected to improve the cost-effectiveness ratio of screening, the benefits of approaches like pretreatment patient stratification by clinical, histologic, and genetic scores remain uncertain, while the worthiness of excluding patients with severe comorbidities and aged individuals is still debated.

Hepatocellualar carcinoma serum markers

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

LecT-Hepa, a glyco-marker derived from multiple lectins, as a predictor of liver fibrosis in chronic hepatitis C patients

Assessment of liver fibrosis in patients with chronic hepatitis C (CHC) is critical for predicting disease progression and determining future antiviral therapy. LecT-Hepa, a new glyco-marker derived from fibrosis-related glyco-alteration of serum alpha 1-acid glycoprotein, was used to differentiate cirrhosis from chronic hepatitis in a single-center study. Herein, we aimed to validate this new glyco-marker for estimating liver fibrosis in a multicenter study. Overall, 183 CHC patients were recruited from 5 liver centers. The parameters Aspergillus oryzae lectin (AOL) / Dature stramonium lectin (DSA) and Maackia amurensis lectin (MAL)/DSA were measured using a bedside clinical chemistry analyzer in order to calculate LecT-Hepa levels. The data were compared with those of seven other noninvasive biochemical markers and tests (hyaluronic acid, tissue inhibitor of metalloproteases-1, platelet count, aspartate aminotransferase-to-platelet ratio index [APRI], Forns index, Fib-4 index, and Zeng's score) for assessing liver fibrosis using the receiver-operating characteristic curve. LecT-Hepa correlated well with the fibrosis stage as determined by liver biopsy. The area under the curve (AUC), sensitivity, and specificity of LecT-Hepa were 0.802, 59.6%, and 89.9%, respectively, for significant fibrosis; 0.882, 83.3%, and 80.0%, respectively, for severe fibrosis; and 0.929, 84.6%, and 88.5%, respectively, for cirrhosis. AUC scores of LecT-Hepa at each fibrosis stage were greater than those of the seven aforementioned noninvasive tests and markers.

CONCLUSION

The efficacy of LecT-Hepa, a glyco-marker developed using glycoproteomics, for estimating liver fibrosis was demonstrated in a multicenter study. LecT-Hepa given by a combination of the two glyco-parameters is a reliable method for determining the fibrosis stage and is a potential substitute for liver biopsy.

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.

Identification and confirmation of differentially expressed fucosylated glycoproteins in the serum of ovarian cancer patients using a lectin array and LC-MS/MS

In order to discover potential glycoprotein biomarkers in ovarian cancer, we applied a lectin array and Exactag labeling based quantitative glycoproteomics approach. A lectin array strategy was used to detect overall lectin-specific glycosylation changes in serum proteins from patients with ovarian cancer and those with benign conditions. Lectins, which showed significant differential response for fucosylation, were used to extract glycoproteins that had been labeled using isobaric chemical tags. The glycoproteins were then identified and quantified by LC-MS/MS, and five glycoproteins were found to be differentially expressed in the serum of ovarian cancer patients compared to benign diseases. The differentially expressed glycoproteins were further confirmed by lectin-ELISA and ELISA assay. Corticosteroid-binding globulin (CBG), serum amyloid p component (SAP), complement factor B (CFAB), and histidine-rich glycoprotein (HRG) were identified as potential markers for differentiating ovarian cancer from benign diseases or healthy controls. A combination of CBG and HRG (AUC = 0.825) showed comparable performance to CA125 (AUC = 0.829) in differentiating early stage ovarian cancer from healthy controls. The combination of CBG, SAP, and CA125 showed improved performance for distinguishing stage III ovarian cancer from benign diseases compared to CA125 alone. The ability of CBG, SAP, HRG, and CFAB to differentiate the serum of ovarian cancer patients from that of controls was tested using an independent set of samples. Our findings suggest that glycoprotein modifications may be a means to identify novel diagnostic markers for detection of ovarian cancer.

Recent progress in quantitative glycoproteomics

Protein glycosylation is acknowledged as one of the major posttranslational modifications that elicit significant effects on protein folding, conformation, distribution, stability, and activity. The changes in glycoprotein abundance, glycosylation degree, and glycan structure are associated with a variety of diseases. Therefore, the quantitative study of glycoproteomics has become a new and popular research topic, and is quickly emerging as an important technique for biomarker discovery. Mass spectrometry-based protein quantification technologies provide a powerful tool for the systematic and quantitative assessment of the quantitative differences in the protein profiles of different samples. Combined with various glycoprotein/glycopeptide enrichment strategies and other glycoprotein analysis methods, these techniques have been further developed for application in quantitative glycoproteomics. A comprehensive quantitative analysis of the glycoproteome in a complex biological sample remains challenging because of the enormous complexity of biological samples, intrinsic characteristics of glycoproteins, and lack of universal quantitative technology. In this review, recently developed technologies in quantitative glycoproteome, especially those focused on two of the most common types of glycosylation (N-linked and O-linked glycoproteome), were summarized. The strengths and weaknesses of the various approaches were also discussed.

Clinical significance of elevated alpha-foetoprotein (AFP) in patients with chronic hepatitis C without hepatocellular carcinoma in upper EGYPT

BACKGROUND AND STUDY AIMS

Egypt has the highest prevalence of hepatitis C in the world. Alpha-foetoprotein (AFP) is important in the diagnosis of hepatocellular carcinoma (HCC), but elevated AFP levels have also been observed in chronic hepatitis C (CHC) without HCC. We evaluated the clinical correlation between elevated AFP levels and CHC. We analysed data from a population-based cohort of patients with hepatitis C virus (HCV) infection to assess the prevalence of elevated serum AFP, to determine its association with clinical and virologic parameters and with clinical outcomes.

PATIENTS AND METHODS

From December 2009 to April 2011, 121 patients with no evidence of HCC with regular abdominal ultrasound or other imaging studies (multislice computed tomography (MSCT) or magnetic resonance imaging (MRI)) were controlled by a chart review.

RESULTS

The prevalence of elevated AFP ≥10ngml(-1) was 11.6%. Univariate analysis revealed that fibrosis stage III/IV, alanine aminotransferase (ALT) more than 45IUl(-1) and platelet count less than 150×10(9) l(-1) were significantly associated with elevated AFP. Multivariate analysis revealed that the independent variable associated with elevated serum AFP was fibrosis stage III/IV, p=0.015. Multivariate analysis also revealed that AST>45IUl(-1) and AFP ≥10 ngml(-1) were associated with advanced fibrosis using a cut-off AFP value >10 ngml(-1). The sensitivity and specificity of diagnosing fibrosis score III/IV were 26.1% and 97.3%, respectively.

CONCLUSIONS

Elevated AFP levels were observed in 11.65% of patients with CHC. Elevated AFP levels correlated positively with fibrosis stage III/IV; ALT elevation, thrombocytopenia and AFP ≥10 ngml(-1) were associated with advanced fibrosis.

Microfluidic digital isoelectric fractionation for rapid multidimensional glycoprotein analysis

Here we present an integrated microfluidic device for rapid and automated isolation and quantification of glycoprotein biomarkers directly from biological samples on a multidimensional analysis platform. In the first dimension, digital isoelectric fractionation (dIEF) uses discrete pH-specific membranes to separate proteins and their isoforms into precise bins in a highly flexible spatial arrangement on-chip. dIEF provides high sample preconcentration factors followed by immediate high-fidelity transfer of fractions for downstream analysis. We successfully fractionate isoforms of two potential glycoprotein cancer markers, fetuin and prostate-specific antigen (PSA), with 10 min run time, and results are compared qualitatively and quantitatively to conventional slab gel IEF. In the second dimension, functionalized monolithic columns are used to capture and detect targeted analytes from each fraction. We demonstrate rapid two-dimensional fractionation, immunocapture, and detection of C-reactive protein (CRP) spiked in human serum. This rapid, flexible, and automated approach is well-suited for glycoprotein biomarker research and verification studies and represents a practical avenue for glycoprotein isoform-based diagnostic testing.

Glycans as cancer biomarkers

BACKGROUND

Non-invasive biomarkers, such as those from serum, are ideal for disease prognosis, staging and monitoring. In the past decade, our understanding of the importance of glycosylation changes with disease has evolved.

SCOPE OF REVIEW

We describe potential biomarkers derived from serum glycoproteins for liver, pancreatic, prostate, ovarian, breast, lung and stomach cancers. Methods for glycan analysis have progressed and newly developed high-throughput platform technologies have enabled the analysis of large cohorts of samples in an efficient manner. We also describe this evolution and trends to follow in the future.

MAJOR CONCLUSIONS

Many convincing examples of aberrant glycans associated with cancer have come about from glycosylation analyses. Most studies have been carried out to identify changes in serum glycan profiles or through the isolation and identification of glycoproteins that contain these irregular glycan structures. In a majority of cancers the fucosylation and sialylation expression are found to be significantly modified. Therefore, these aberrations in glycan structures can be utilized as targets to improve existing cancer biomarkers.

GENERAL SIGNIFICANCE

The ability to distinguish differences in the glycosylation of proteins between cancer and control patients emphasizes glycobiology as a promising field for potential biomarker identification. Furthermore, the high-throughput and reproducible nature of the chromatography platform have highlighted extensive applications in biomarker discovery and allowed integration of glycomics with other -omics fields, such as proteomics and genomics, making systems glycobiology a reality. This article is part of a Special Issue entitled Glycoproteomics.

Diagnostic accuracy of α-fetoprotein and des-γ-carboxy prothrombin in screening for hepatocellular carcinoma in liver transplant candidates

AIM

  Although hepatocellular carcinoma (HCC)-specific serum tumor markers, α-fetoprotein (AFP) and des-γ-carboxy prothrombin (DCP), are used in the screening for HCC, their utility in pre-transplantation evaluation is not well established. This study aimed to evaluate the accuracy of AFP and DCP measurement for the diagnosis of HCC in liver transplant candidates.

METHODS

  A total of 315 consecutive adult patients (174 men and 141 women, mean age 52 years), who were to receive liver transplantation for end-stage liver diseases, were enrolled. The pre-transplant levels of AFP and DCP were compared with the histopathology of explanted liver.

RESULTS

  Hepatocellular carcinoma was present in the explanted liver of 106 recipients (median number of nodules 2, mean diameter 2.5 cm). The area under receiver operating characteristic curve for the diagnosis of HCC was 0.83 (95% confidence interval, 0.78-0.88) for AFP and 0.47 (0.41-0.54) for DCP. With the cut-off value of 100 mAU/mL, 20/106 (18.9%) patients with HCC and 54/194 (27.8%) patients without HCC were positive for DCP. DCP positivity was associated with vascular invasion, tumor differentiation and size among patients with HCC, which was associated with albumin level among patients without HCC. Vitamin K was administered prior to transplantation to 20 patients who were positive for DCP (two with and 18 without HCC), resulting in a decrease in DCP levels in 19 of them.

CONCLUSIONS

  Serum DCP levels may be raised in end-stage liver disease patients without HCC, and cannot be used as a reliable marker for HCC among liver transplant candidates.

α1-3/4 fucosylation at Asn 241 of β-haptoglobin is a novel marker for colon cancer: a combinatorial approach for development of glycan biomarkers

Aberrant glycosylation has been observed in many types of cancer, but the mechanism of glycosylation change is still poorly understood. To elucidate relationships between glycosylation and colon cancer progression, we analyzed glycosylation status of β-haptoglobin (β-Hp) obtained from 46 cancer patients, 14 inflammatory bowel disease patients and 38 normal subjects. Aleuria aurantia lectin reactivity with cancer β-Hp was much higher than in the other two study groups. These results were confirmed by lectin blotting and microarray assay using other lectins directed to fucosyl residues. Levels of such glycans were correlated with stage of colon cancer progression. Reactivity with fucosylated glycans was eliminated by treatment with α1-3/4 fucosidase but not α1-6 fucosidase, indicating that enhanced lectin reactivity with the fucose moiety of colon cancer β-Hp is due to Fucα1-3/4GlcNAc. Moreover, site-specific glycan occupancy was determined by sequential LC/MS analysis. Mass spectrometric analysis showed that fucosylation of β-Hp was higher in colon cancer patients than in other subjects. In particular, fucosylation at Asn 241 of β-Hp in sera of colon cancer patients was clearly higher than in the other groups, and the ratio of fucosylated glycopeptides containing Asn 241 decreased greatly after treatment with α1-3/4 fucosidase. In conclusion, the level of α1-3/4 fucosyl epitope at Asn 241 of β-Hp is potentially useful as a novel marker for colon cancer.

LecT-Hepa: A triplex lectin-antibody sandwich immunoassay for estimating the progression dynamics of liver fibrosis assisted by a bedside clinical chemistry analyzer and an automated pretreatment machine

BACKGROUND

A quantitative analysis of glyco-alteration in serum glycoproteins provides glyco-parameters for estimating the progression of liver fibrosis. In the analysis of glycans, a manual pretreatment process for clinical specimens leads to a complicated manipulation and loss-of-clinical implementation of the assay.

METHOD

We evaluated an automated triplex lectin-antibody sandwich immunoassay assisted by an automated protein purification system (ED-01) and a bedside clinical chemistry analyzer (HISCL) for the acquisition of two glyco-parameters (AOL/DSA and MAL/DSA) derived from a fibrosis-related glyco-alteration of serum alpha1-acid glycoprotein (AGP).

RESULTS

We adjusted the auto-machines with their accuracy set to CV <5.0% (ED-01) and <1.0% (HISCL). AGP samples were enriched from 275 serum specimens. Two glyco-parameters obtained by HISCL showed a linear correlation with that from a reported assay (R>0.90). The formula for monitoring fibrosis (LecT-Hepa) was given by a combination of the glyco-parameters. This correlated with the fibrosis stage from biopsy (R=0.68) and diagnosed severe fibrosis and cirrhosis. It was superior to that of FIB-4 index.

CONCLUSIONS

We automated a multilectin-assisted immunoassay with an order of magnitude reduction of operation time without any loss-of-accuracy. LecT-Hepa is a reliable method to assess fibrosis-dynamics from moderate fibrosis to cirrhosis.

Development of fluorescent probes for the detection of fucosylated N-glycans using an Aspergillus oryzae lectin

The α(1,6)-fucose attached to the core N-glycan (core fucose) of glycoproteins has been known to play essential roles in various pathophysiological events, including oncogenesis and metastasis. Aspergillus oryzae lectin (AOL) encoded by the fleA gene has been reported to bind to N-glycans containing core fucose. The fleA gene encoding AOL was cloned into an Escherichia coli expression vector and then fused with genes of fluorescent proteins for production of fusion proteins. The resulting FleA-fluorescent fusion proteins were expressed well in E. coli and shown to detect glycoproteins containing N-glycans with core fucose by lectin blot assay. It was also shown to bind to the surface of cancer cells highly expressing the fucosyltransferase VIII for attachment of core fucose. Surprisingly, we found that FleA-fluorescent fusion proteins could be internalized into the intracellular compartment, early endosome, when applied to live cells. This internalization was shown to occur through a clathrin-mediated pathway by endocytosis inhibitor assay. Taken together, these results suggest that FleA-fluorescent fusion proteins can be employed as a valuable fluorescent probe for the detection of fucosylated glycans and/or a useful vehicle for delivery of substances to the inside of cells.

Novel Lens culinaris agglutinin-reactive fraction of α-fetoprotein: a biomarker of hepatocellular carcinoma recurrence in patients with low α-fetoprotein concentrations

BACKGROUND

Lens culinaris agglutinin-reactive fraction of α-fetoprotein (AFP-L3) is a specific marker used to detect hepatocellular carcinoma (HCC). However, its clinical utility is not sufficient in patients with low total AFP concentrations because of limitations in instrument sensitivity. Recent advances have led to the introduction of a highly sensitive AFP-L3% assay (sensitive AFP-L3%), provided by a novel on-chip, liquid-phase binding assay. This cross-sectional study was conducted to evaluate the clinical significance of the sensitive AFP-L3% in determining HCC recurrence in patients with low total AFP concentrations.

METHODS

A total of 370 consecutive patients with HCC were screened within 1-3 months of locoregional treatment, and 215 of the 370 patients showed serum AFP <20 ng/ml. Total AFP, sensitive AFP-L3%, and des-gamma-carboxy prothrombin (DCP) were measured in those 215 patients and HCC recurrence was evaluated by radiological findings. Optimal cutoff values of the markers for detecting HCC recurrence were obtained on the basis of receiver operating characteristic (ROC) curve.

RESULTS

The area under the ROC curve of the total AFP, sensitive AFP-L3%, and DCP in HCC patients with serum AFP <20 ng/ml were 0.638, 0.724, and 0.779, respectively. The diagnostic accuracies of the total AFP, sensitive AFP-L3%, and DCP were 60.9% (cutoff value 5 ng/ml), 67.7% (cutoff value 7%), and 64.6% (cutoff value 40 ng/ml), respectively.

CONCLUSIONS

The new sensitive AFP-L3% assay provides great utility in determining HCC recurrence in patients with low AFP concentrations. Further studies focusing on the combinatorial use of the markers (total AFP, sensitive AFP-L3%, and DCP) are required.

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.

History and recent progress in evaluation of the fucosylated alpha-fetoprotein fraction

See article in J. Gastroenterol. Hepatol. 2011; 26: 739–744.

Lens culinaris agglutinin-reactive fraction of AFP is a useful prognostic biomarker for survival after repeat hepatic resection for HCC

BACKGROUND AND AIM

Repeat hepatic resection for recurrent hepatocellular carcinoma (HCC) is effective in improving long-term outcome in selected patients. In the present study, we attempted to identify the prognostic factors influencing overall and recurrence-free survival after the second hepatic resection.

METHODS

From 1 September 1997 to 30 September 2009, 329 consecutive patients with HCC underwent surgical exploration at Yamanashi University Hospital, Japan. Of these, 35 patients underwent curative, second hepatic resection. The survival results in the 35 patients were analyzed retrospectively, and prognostic factors were determined.

RESULTS

The univariate analysis revealed that Child-Pugh B, a Lens culinaris agglutinin-reactive fraction of α-fetoprotein (AFP-L3) value more than 15%, and multiple tumors, were associated with significantly worse overall survival (P=0.010, P=0.0003, and P=0.037, respectively) and only AFP-L3 >15% was associated with significantly worse recurrence-free survival after the second hepatic resection (P=0.008). By multivariate analysis, only AFP-L3 >15% was an independent predictor of adverse overall survival. The 1-, 3-, and 5-year survival rates after the second hepatic resection of 27 HCC patients with low AFP-L3 (≤15%) were 100%, 100%, and 91.7%, respectively, whereas the corresponding survival rates of eight HCC patients with high AFP-L3 (>15%) were 100%, 47.6%, and 23.8%, respectively.

CONCLUSIONS

The preoperative AFP-L3 level was a useful prognostic biomarker for survival after repeat hepatic resection.

Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein as a marker of prognosis and a monitor of recurrence of hepatocellular carcinoma after curative liver resection

BACKGROUND

The aim of this study was to determine the role of Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3) as a prognostic marker and a monitor marker of recurrence after curative resection of hepatocellular carcinoma (HCC).

METHODS

From December 2002 to May 2004, 395 consecutive patients with HCC who underwent curative partial hepatectomy were included in the study. The tumor characteristics and clinical outcomes of patients with positive preoperative and postoperative AFP-L3 were compared with those with negative results.

RESULTS

A high ratio of AFP-L3 to total AFP was an indicator of pathologic aggressiveness. Patients with positive preoperative AFP-L3 had significantly earlier recurrence (median time to recurrence 22.0 ± 2.4 months vs 45.0 ± 6.9 months, P < .001) when compared with those with negative preoperative results. Significantly more patients with continuously positive or negative-turn-positive AFP-L3 results after surgery developed recurrence, particularly distant metastases, when compared with patients with continuously negative AFP-L3 results. The overall and disease-free survivals were significantly shorter in the positive than the negative preoperative AFP-L3 group. The overall and disease-free survivals were significantly shorter in the continuously positive and the negative-turn-positive than the continuously negative postoperative AFP-L3 group.

CONCLUSION

Positive preoperative AFP-L3 and continuously positive or negative-turn-positive AFP-L3 results after surgery predicted a more aggressive tumor behavior, higher tumor recurrence, and poorer clinical outcomes. HCC patients with an increased proportion of AFP-L3 to total AFP should be more aggressively treated and closely followed-up.

Alterations of glycan branching and differential expression of sialic acid on alpha fetoprotein among hepatitis patients

The level of serum glycoproteins and their glycosylation pattern change in liver diseases including hepatocellular carcinoma (HCC). Some of them, especially alpha fetoprotein (AFP), serve as useful biomarkers for HCC. The present investigation showed high level of AFP in hepatitis B cirrhosis (HBV-LC) and hepatitis C cirrhosis (HCV-LC) patients. However, increase of AFP level was not significantly high in chronic hepatitis B (HBV-CH) as determined by ELISA using monoclonal anti-human AFP (mAb-AFP). The differential expression of sialic acid linkage was observed in HBV-CH and HCV-LC by ELISA; the former bound strongly with Sambucus nigra agglutinin (SNA), which has exclusive binding specificity for NeuAcα2-6-, whereas HCV-LC reacted preferably with Maackia amurensis agglutinin (MAA) which recognizes NeuAcα2-3-. There was significantly high glycan branching in HBV-LC and HCV-LC in comparison to controls as illustrated by concanavalin A. This was further confirmed by Phaseolus vulgaris erythroagglutinin (E-PHA) and Datura stramonium agglutinin (DSA). Enhanced fucosylation of AFP was observed in HBV-LC, HCV-LC and HCC patients by ELISA using fucose binding Aleuria aurantia lectin; however, maximum binding was found in HCC. Fucosylation with α1-6 linkage was further confirmed by Lens culinaris agglutinin (LCA). From the above results it is concluded that the changes in concentration of AFP, differential expression of sialic acid, increase of glycan branching and fucosylation have a prognostic value of hepatitis and it could be possible that lectin-based assay with AFP can aid in diagnosis of hepatitis diseases besides clinical examination and routine laboratory investigation.

Serum markers of hepatocellular carcinoma

BACKGROUND

The hepatocellular carcinoma is one of the most common malignant tumors and carries a poor survival rate. The management of patients at risk for developing HCC remains intricate.

METHODS

A literature search identified potential markers for hepatocellular carcinoma. These markers were analysed and justification was provided for these factors' inclusion to (or exclusion from) the markers of hepatocellular carcinoma (HCC). A search of the literature was made using cancer literature and the PubMed database for the following keywords: "markers and HCC," "Lens culinaris agglutinin reactive AFP (AFP-L3) and HCC," "Des-γ-carboxy prothrombin (DCP) and HCC," "Glypican-3 and HCC," "Chromogranin A and HCC," "Transforming growth factor β1(TGF) and HCC," "α-l-fucosidase (AFU) and HCC," "Golgi protein-73 (GP73) and HCC," "Hepatocyte growth factor (HGF) and HCC," "Nervous growth factor (NGF) and HCC."

CONCLUSIONS

Despite the large number of studies devoted to the immunohistochemistry of HCC, at the present time, the absolute positive and negative markers for HCC are still lacking, and even those characterized by very high sensitivity and specificity do not have an universal diagnostic usefulness. Given the poor response to current therapies, a better understanding of the molecular pathways active in this disease could potentially provide new targets for therapy. However, AFP shows a low sensitivity, therefore other biomarkers have been developed to make an early diagnosis and improve patients' prognosis.

N-glycan based models improve diagnostic efficacies in hepatitis B virus-related hepatocellular carcinoma

The early diagnosis of hepatocellular carcinoma (HCC) is of great clinical desirable due to lack of specific and sensitive markers. Alterations in the sugar chains of glycoprotein synthesized by the liver contribute to the molecular basis of abnormalities in carcinogenesis. This study aims to construct and assess the diagnostic value of N-glycan based diagnostic model in HCC identification and follow-up. A total of 393 subjects including HBV-related HCC, liver fibrosis and healthy controls were recruited. Follow-up was carried out before and after surgical treatment in HCC. N-glycome of serum glycoprotein was profiled by DNA sequencer-assisted fluorophore-assisted carbohydrate electrophoresis (DSA-FACE). Multiparameters diagnostic models were constructed based on N-glycan markers. The result found that 2 N-glycan structure abundances (NG1A2F, Peak 4; NA3Fb, Peak 9) were useful as N-glycan markers. The diagnostic efficacy of the log ratio [log(p9/4)] was similar to that of AFP in differentiating HCC from fibrosis. The accuracy and sensitivity of the diagnostic model combining AFP and N-glycan markers (Cscore B) were increased 7-10% compared with that of AFP. Log(p9/4) was more efficient in monitoring the progression of HCC with regarding to vascular invasion at improved specificity (16%) and accuracy (8%) compared with that of AFP. The N-glycan markers were found to be changed significantly after surgical resection in HCC follow-up. We conclude that the branching alpha (1,3)-fucosylated triantennary glycan and a biantennary glycan are promising as N-glycan markers. The diagnostic models based on the N-glycan markers and AFP improve the efficacy in HCC diagnosis and progression monitoring.

Asian Pacific Association for the Study of the Liver consensus recommendations on hepatocellular carcinoma

INTRODUCTION

The Asian Pacific Association for the Study of the Liver (APASL) convened an international working party on the management of hepatocellular carcinoma (HCC) in December 2008 to develop consensus recommendations.

METHODS

The working party consisted of expert hepatologist, hepatobiliary surgeon, radiologist, and oncologist from Asian-Pacific region, who were requested to make drafts prior to the consensus meeting held at Bali, Indonesia on 4 December 2008. The quality of existing evidence and strength of recommendations were ranked from 1 (highest) to 5 (lowest) and from A (strongest) to D (weakest), respectively, according to the Oxford system of evidence-based approach for developing the consensus statements.

RESULTS

Participants of the consensus meeting assessed the quality of cited studies and assigned grades to the recommendation statements. Finalized recommendations were presented at the fourth APASL single topic conference on viral-related HCC at Bali, Indonesia and approved by the participants of the conference.

Asian Pacific Association for the Study of the Liver consensus recommendations on hepatocellular carcinoma

INTRODUCTION

The Asian Pacific Association for the Study of the Liver (APASL) convened an international working party on the management of hepatocellular carcinoma (HCC) in December 2008 to develop consensus recommendations.

METHODS

The working party consisted of expert hepatologist, hepatobiliary surgeon, radiologist, and oncologist from Asian-Pacific region, who were requested to make drafts prior to the consensus meeting held at Bali, Indonesia on 4 December 2008. The quality of existing evidence and strength of recommendations were ranked from 1 (highest) to 5 (lowest) and from A (strongest) to D (weakest), respectively, according to the Oxford system of evidence-based approach for developing the consensus statements.

RESULTS

Participants of the consensus meeting assessed the quality of cited studies and assigned grades to the recommendation statements. Finalized recommendations were presented at the fourth APASL single topic conference on viral-related HCC at Bali, Indonesia and approved by the participants of the conference.

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.

Serum alpha-fetoprotein levels during and after interferon therapy and the development of hepatocellular carcinoma in patients with chronic hepatitis C

The association between serum alpha-fetoprotein (AFP) levels during and after interferon (IFN) therapy and the development of hepatocellular carcinoma (HCC) was evaluated in patients with chronic hepatitis C (CHC). A total of 263 patients treated by IFN with or without ribavirin were enrolled in the study. Serum AFP levels during and after IFN therapy were investigated retrospectively, and statistical analysis was performed to identify the factors associated with HCC development. During IFN therapy, serum AFP levels significantly decreased, regardless of virologic response to treatment. Increased serum AFP levels (>or=10 ng/ml) at the end of IFN therapy (EOT) was a close-to-significant variable affecting the development of HCC (P = 0.057), and a significantly higher cumulative incidence of HCC was seen in patients with increased serum AFP levels at EOT (P = 0.021). Serum AFP level at EOT is a possible predictor of HCC in CHC patients after IFN therapy.

Clinical evaluation of serum alpha-fetoprotein-IgM immune complexes on the diagnosis of primary hepatocellular carcinoma

We evaluated clinical significance of serum alpha-fetoprotein (AFP)-IgM immune complexes, in comparison with free AFP, on the diagnosis of primary hepatocellular carcinoma (HCC). Serum levels of AFP-IgM immune complexes and free AFP were determined by the ELISA method and electrochemiluminescence, respectively, in 103 healthy controls, 74 patients suffering from primary HCC, 27 patients suffering from liver cirrhosis, and 63 patients suffering from chronic hepatitis. The best cut-off value of AFP-IgM and free AFP for diagnosis of primary HCC were 300 AU/mL and 10 microg/L respectively, according to the area under the curve (AUC) in this study. The sensitivity of AFP-IgM and free AFP were 64.9 and 79.7%, and the specificity were 75.6 and 80.3%, respectively, when all cases of primary HCC were analyzed, and the AUC of free AFP was larger than that of AFP-IgM (0.85 vs. 0.72, Z=3.21). However, in case of primary HCC at early stages (stages I and II) were analyzed, the AUC of AFP-IgM was larger than that of free AFP (0.91 vs. 0.82, Z=1.73), which demonstrated that the sensitivity of AFP-IgM and free AFP were 94.4 and 72.2%, and the specificity were 81.9 and 79.9%, respectively. When both AFP-IgM and free AFP were positive, the specificity of diagnosis of primary HCC was 89.1%, and the efficacy was 79.0%. It is concluded that either sensitivity or specificity of serum level of AFP-IgM immune complexes was higher than that of free AFP in the diagnosis of primary HCC at early stages. As there was false positive AFP-IgM existed in the patients suffering from cirrhosis and chronic hepatitis, the combination of free AFP and AFP-IgM could significantly increase specificity and decrease false negative and/or false positive in the primary HCC at early stages.

Early Detection of Cancer: Immunoassays for Plasma Tumor Markers

BACKGROUND: Plasma tumor biomarkers are widely used clinically for monitoring response to therapy and detecting cancer recurrence. However, only a limited number of them have been effectively used for the early detection of cancer. OBJECTIVE: To review plasma tumor markers used clinically for the early detection of cancer and to provide expert opinion about future directions. METHODS: Literature review, as well as our expert opinion, of plasma tumor markers that have been widely accepted for the early detection of cancer. RESULTS: In the United States, only prostate specific antigen (PSA), cancer antigen 125 (CA125), and alpha-fetoprotein (AFP) have been clinically used for the early detection of prostate, ovarian, and liver cancers, respectively. Both analytical and clinical issues related to the use of these three markers were discussed. CONCLUSION: Few plasma tumor markers have been used effectively for the early detection of cancer, mainly due to their limited sensitivity and/or specificity. Multiple approaches have been developed to improve the clinical performance of tumor markers for the early detection of cancer. Metrological traceability and antibody specificity are important issues to ensure comparability of immunoassays for the measurement of plasma tumor markers.

Clinical implications of alpha-fetoprotein in chronic hepatitis C

BACKGROUND/PURPOSE

Chronic hepatitis C (CHC) shows a significant association with cirrhosis and hepatocellular carcinoma (HCC). Alpha-fetoprotein (AFP) is important in the diagnosis of HCC, but elevated AFP levels have also been observed in CHC without HCC. We evaluated the clinical correlation between elevated AFP levels and CHC.

METHODS

From April 1999 to November 2004, 654 CHC patients with no evidence of HCC from imaging studies were collected by chart review.

RESULTS

The prevalence of elevated AFP levels (>or= 15 ng/mL) was 23.9%. Univariate analysis revealed that age, histological activity index (HAI) fibrosis score of 3/4, HAI inflammation score >or= 7, aspartate aminotransferase (AST) and alanine transaminase (ALT) levels, AST/ALT ratio, and total bilirubin level were associated with elevated AFP levels. Multivariate analysis revealed that age (>or= 55 vs. < 55 years), HAI inflammation score (>or= 7 vs. < 7), ALT (> 150 vs. <or= 150 U/L), and platelet count (<or= 150 x 109 vs. > 150 x 109 cells/L) were associated with elevated AFP levels. Multivariate analysis also revealed that hepatitis C virus (HCV) genotype 1b, platelet count <or= 150 x 109 cells/L, AST > 80 U/L and AFP >or= 6 ng/mL were associated with advanced fibrosis. Using a cut-off AFP level of >or= 6.0 ng/mL, the sensitivity and specificity of diagnosing fibrosis score 3/4 was 74.3% and 68.4%, respectively. Using a cut-off AFP level of >or= 15.0 ng/mL, the sensitivity and specificity of diagnosing fibrosis score 3/4 was 35.7% and 91.1%, respectively.

CONCLUSION

Elevated AFP levels were observed in 23.9% of patients with CHC. Elevated AFP levels correlated positively with age, HAI inflammation score, ALT elevation, and thrombocytopenia. In addition, HCV genotype 1b, thrombocytopenia, AST elevation, and AFP level >or= 6 ng/mL were associated with advanced fibrosis.

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.

Automated immunoassay system for AFP-L3% using on-chip electrokinetic reaction and separation by affinity electrophoresis

Implementation of the on-chip immunoassay for alpha-fetoprotein (AFP)-L3% was achieved using a fully automated microfluidic instrument platform that will prepare the chip and run the assay with a total assay time of less than 10min. Reagent/sample mixing, concentration, and reaction in microfluidic channels occur by the electrokinetic analyte transport assay (EATA) technique, enabling the integration of all assay steps on-chip. The determination of AFP-L3%, a biomarker for hepatocellular carcinoma, was achieved by the presence of Lens culinaris agglutinin in the separation channel, causing separation of the fucosylated isoform, AFP-L3, from the nonfucosylated AFP-L1 by lectin affinity electrophoresis. Laser-induced-fluorescence (LIF) detection was used to quantitate the labeled immunocomplexes. The limit of detection (LOD) was 0.1ng/ml AFP, and assay precision of less than 2% coefficient of variation (CV) was obtained for quantitation from 24 to 922ng/ml total AFP in spiked serum samples. Assay precision of less than 3% CV was obtained for AFP-L3% measurements from 8.5 to 81%. Furthermore, good correlation of test results for 68 patient serum samples with a commercially available reference method (LiBASys assay for AFP-L3%) was obtained, with r(2)=0.981 and slope=1.03.