Fucosylated fraction of alpha-fetoprotein, L3, as a useful prognostic factor in patients with hepatocellular carcinoma with special reference to low concentrations of serum alpha-fetoprotein

Application of Lectin Microarrays for Biomarker Discovery

Many proteins in living organisms are glycosylated. As their glycan patterns exhibit protein-, cell-, and tissue-specific heterogeneity, changes in the glycosylation levels could serve as useful indicators of various pathological and physiological states. Thus, the identification of glycoprotein biomarkers from specific changes in the glycan profiles of glycoproteins is a trending field. Lectin microarrays provide a new glycan analysis platform, which enables rapid and sensitive analysis of complex glycans without requiring the release of glycans from the protein. Recent developments in lectin microarray technology enable high-throughput analysis of glycans in complex biological samples. In this review, we will discuss the basic concepts and recent progress in lectin microarray technology, the application of lectin microarrays in biomarker discovery, and the challenges and future development of this technology. Given the tremendous technical advancements that have been made, lectin microarrays will become an indispensable tool for the discovery of glycoprotein biomarkers.

Prediction of hepatocellular carcinoma biological behavior in patient selection for liver transplantation

Morphological criteria have always been considered the benchmark for selecting hepatocellular carcinoma (HCC) patients for liver transplantation (LT). These criteria, which are often inappropriate to express the tumor’s biological behavior and aggressiveness, offer only a static view of the disease burden and are frequently unable to correctly stratify the tumor recurrence risk after LT. Alpha-fetoprotein (AFP) and its progression as well as AFP-mRNA, AFP-L3%, des-γ-carboxyprothrombin, inflammatory markers and other serological tests appear to be correlated with post-transplant outcomes. Several other markers for patient selection including functional imaging studies such as ¹⁸F-FDG-PET imaging, histological evaluation of tumor grade, tissue-specific biomarkers, and molecular signatures have been outlined in the literature. HCC growth rate and response to pre-transplant therapies can further contribute to the transplant evaluation process of HCC patients. While AFP, its progression, and HCC response to pre-transplant therapy have already been used as a part of an integrated prognostic model for selecting patients, the utility of other markers in the transplant setting is still under investigation. This article intends to review the data in the literature concerning predictors that could be included in an integrated LT selection model and to evaluate the importance of biological aggressiveness in the evaluation process of these patients.

Glycosylation-Based Serum Biomarkers for Cancer Diagnostics and Prognostics

Cancer is the second most common cause of death in developed countries with approximately 14 million newly diagnosed individuals and over 6 million cancer-related deaths in 2012. Many cancers are discovered at a more advanced stage but better survival rates are correlated with earlier detection. Current clinically approved cancer biomarkers are most effective when applied to patients with widespread cancer. Single biomarkers with satisfactory sensitivity and specificity have not been identified for the most common cancers and some biomarkers are ineffective for the detection of early stage cancers. Thus, novel biomarkers with better diagnostic and prognostic performance are required. Aberrant protein glycosylation is well known hallmark of cancer and represents a promising source of potential biomarkers. Glycoproteins enter circulation from tissues or blood cells through active secretion or leakage and patient serum is an attractive option as a source for biomarkers from a clinical and diagnostic perspective. A plethora of technical approaches have been developed to address the challenges of glycosylation structure detection and determination. This review summarises currently utilised glycoprotein biomarkers and novel glycosylation-based biomarkers from the serum glycoproteome under investigation as cancer diagnostics and for monitoring and prognostics and includes details of recent high throughput and other emerging glycoanalytical techniques.

Development of M2BPGi: a novel fibrosis serum glyco-biomarker for chronic hepatitis/cirrhosis diagnostics

Many proteins in the living body are glycoproteins, which present glycans linked on their surface. Glycan structures reflect the degree of cell differentiation or canceration and are cell specific. These characteristics are advantageous in the development of various disease biomarkers. Glycoprotein-based biomarkers (glyco-biomarkers) are developed by utilizing the specific changes in the glycan structure on a glycoprotein secreted from the diseased cells of interest. Therefore, quantification of the altered glycan structures is the key to developing a new glyco-biomarker. Glycoscience is a relatively new area of molecular science, and recent advancement of glycotechnologies is remarkable. In the author's institute, new glycoscience technologies have been designed to be efficiently utilized for the development of new diagnostic agents. This paper introduces a strategy for glyco-biomarker development, which was successfully applied in the development of Wisteria floribunda agglutinin-positive Mac-2 binding protein M2BPGi, a liver fibrosis marker now commercially available for clinical use.

Prognostic role of pre-treatment serum AFP-L3% in hepatocellular carcinoma: systematic review and meta-analysis

BACKGROUND

Serum lens culinaris agglutinin-reactive fraction of α-fetoprotein (AFP-L3%) has been widely used for HCC diagnosis and follow-up surveillance as tumor serologic marker. However, the prognostic value of high pre-treatment serum AFP-L3% in patients with hepatocellular carcinoma (HCC) remains controversial. We therefore conduct a meta-analysis to assess the relationship between high pre-treatment serum AFP-L3% and clinical outcome of HCC.

METHODS

Eligible studies were identified through systematic literature searches. A meta-analysis of fifteen studies (4,465 patients) was carried out to evaluate the association between high pre-treatment serum AFP-L3% and overall survival (OS) and disease-free survival (DFS) in HCC patients. Sensitivity and subgroup analyses were also conducted in this meta-analysis.

RESULTS

Our analysis results showed that high pre-treatment serum AFP-L3% implied poor OS (HR: 1.65, 95%CI: 1.45-1.89 p<0.00001) and DFS (HR: 1.80, 95% CI: 1.49-2.17 p<0.00001) of HCC. Subgroup analysis revealed that there was association between pre-treatment serum AFP-L3% and endpoint (OS and DFS) in low AFP concentration HCC patients (HR: 1.96, 95% CI: 1.24-3.10, p = 0.004; HR: 2.53, 95% CI: 1.09-5.89, p = 0.03, respectively).

CONCLUSION

The current evidence suggests that high pre-treatment serum AFP-L3% levels indicated a poor prognosis for patients with HCC and AFP-L3% may have significant prognostic value in HCC patients with low AFP concentration.

Identification of serum monocyte chemoattractant protein-1 and prolactin as potential tumor markers in hepatocellular carcinoma

Early diagnosis of hepatocellullar carcinoma (HCC) remains a challenge. The current practice of serum alpha-fetoprotein (AFP) measurement is inadequate. Here we utilized a proteomic approach to identify novel serum biomarkers for distinguishing HCC patients from non-cancer controls. We profiled the serum proteins in a group of 58 resectable HCC patients and 11 non-HCC chronic hepatitis B (HBV) carrier samples from the Singapore General Hospital (SGH) using the RayBio® L-Series 507 Antibody Array and found 113 serum markers that were significantly modulated between HCC and control groups. Selected potential biomarkers from this list were quantified using a multiplex sandwich enzyme-linked immunosorbent assay (ELISA) array in an expanded SGH cohort (126 resectable HCC patients and 115 non-HCC chronic HBV carriers (NC group)), confirming that serum prolactin and monocyte chemoattractant protein-1 (MCP-1) were significantly upregulated in HCC patients. This finding of serum MCP-1 elevation in HCC patients was validated in a separate cohort of serum samples from the Mochtar Riady Institute for Nanotechnology, Indonesia (98 resectable HCC, 101 chronic hepatitis B patients and 100 asymptomatic HBV/HCV carriers) by sandwich ELISA. MCP-1 and prolactin levels were found to correlate with AFP, while MCP-1 also correlated with disease stage. Subsequent receiver operating characteristic (ROC) analysis of AFP, prolactin and MCP-1 in the SGH cohort and comparing their area under the ROC curve (AUC) indicated that neither prolactin nor MCP-1 on their own performed better than AFP. However, the combination of AFP+MCP-1 (AUC, 0.974) had significantly superior discriminative ability than AFP alone (AUC, 0.942; p<0.001). In conclusion, prolactin and MCP-1 are overexpressed in HCC and are conveniently quantifiable in patients’ sera by ELISA. MCP-1 appears to be a promising complementary biomarker for HCC diagnosis and this MCP-1+AFP model should be further evaluated as potential biomarker on a larger scale in patients at-risk of HCC.

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.

Clinical utility of serum fucosylated hemopexin in Japanese patients with hepatocellular carcinoma

AIM

  Hepatocellular carcinoma (HCC) is a common clinical problem all over the world. Fucosylated hemopexin (Fuc-Hpx) is a newly reported glycoprotein for the diagnosis of HCC, however, its clinical implications are unclear. The aim of this study was to elucidate the clinical utility of Fuc-Hpx in Japanese patients with HCC.

METHODS

  The sera from 331 HCC patients, 45 with liver cirrhosis (LC), 85 with chronic hepatitis (CH) and 22 healthy people were examined for the expression of Fuc-Hpx; the level was compared with clinical parameters as well as hemopexin (Hpx) expression. The expressions of Fuc-Hpx in 12 HCC tissues and corresponding adjacent non-cancerous liver tissues were also examined.

RESULTS

  No correlation was observed between Hpx and Fuc-Hpx level. The median Fuc-Hpx levels in healthy people and CH, LC and HCC patients were 3.8, 3.7, 6.1 and 7.6 AU/mL, respectively (CH vs LC, P = 0.002; CH vs HCC, P < 0.001; LC vs HCC, P = 0.02). Multivariate analysis revealed that low albumin, low prothrombin time and the presence of HCC were significantly correlated with high Fuc-Hpx (P = 0.013, =0.001 and <0.001, respectively). Among the HCC patients, albumin was correlated with high Fuc-Hpx; however, none of the tumor factors, such as tumor size, tumor number and tumor stage, was correlated with Fuc-Hpx level. The expression of Fuc-Hpx in cancer tissue was not different from that in non-cancerous tissue.

CONCLUSION

  Fuc-Hpx is a valuable biomarker for HCC but it might be a marker for hypercarcinogenic liver rather than a marker for tumor-bearing liver.

Chemically-blocked antibody microarray for multiplexed high-throughput profiling of specific protein glycosylation in complex samples

In this study, we describe an effective protocol for use in a multiplexed high-throughput antibody microarray with glycan binding protein detection that allows for the glycosylation profiling of specific proteins. Glycosylation of proteins is the most prevalent post-translational modification found on proteins, and leads diversified modifications of the physical, chemical, and biological properties of proteins. Because the glycosylation machinery is particularly susceptible to disease progression and malignant transformation, aberrant glycosylation has been recognized as early detection biomarkers for cancer and other diseases. However, current methods to study protein glycosylation typically are too complicated or expensive for use in most normal laboratory or clinical settings and a more practical method to study protein glycosylation is needed. The new protocol described in this study makes use of a chemically blocked antibody microarray with glycan-binding protein (GBP) detection and significantly reduces the time, cost, and lab equipment requirements needed to study protein glycosylation. In this method, multiple immobilized glycoprotein-specific antibodies are printed directly onto the microarray slides and the N-glycans on the antibodies are blocked. The blocked, immobilized glycoprotein-specific antibodies are able to capture and isolate glycoproteins from a complex sample that is applied directly onto the microarray slides. Glycan detection then can be performed by the application of biotinylated lectins and other GBPs to the microarray slide, while binding levels can be determined using Dylight 549-Streptavidin. Through the use of an antibody panel and probing with multiple biotinylated lectins, this method allows for an effective glycosylation profile of the different proteins found in a given human or animal sample to be developed.

Highly sensitive Lens culinaris agglutinin-reactive α-fetoprotein: a new tool for the management of hepatocellular carcinoma

OBJECTIVES

The highly sensitive Lens culinaris agglutinin-reactive α-fetoprotein (hs-AFP-L3), measured using a newly developed method involving microfluidics-based separation technology, was evaluated as a new tool for the management of hepatocellular carcinoma (HCC) in clinical practice.

METHODS

The sensitivity and specificity of hs-AFP-L3 for the diagnosis of HCC and its ability to predict the outcome of patients with HCC were analyzed based on reported studies.

RESULTS

Compared to AFP-L3 measured using conventional methods, the sensitivity of hs-AFP-L3 was markedly higher and the specificity was comparable. In all studies, multivariate analysis found that elevation of hs-AFP-L3 was an independent factor that affected patient survival.

CONCLUSIONS

The use of hs-AFP-L3 improves the true positive rate of patients with HCC at diagnosis, maintaining the high specificity of AFP-L3 and its indicative value for poor prognosis. The utility of this tumor marker for prediction of the development of HCC in high-risk patients under surveillance needs to be investigated.

Clinical significance of the highly sensitive fucosylated fraction of α-fetoprotein in patients with chronic liver disease

BACKGROUND AND AIM

The purpose of the present study was to investigate the clinical significance of the highly sensitive fucosylated fraction of α-fetoprotein (hs-AFP-L3) in patients with chronic liver disease (CLD) and low serum α-fetoprotein (AFP) concentration.

METHODS

A total of 241 patients being treated at our institute with CLD and low serum AFP concentration (3-10 ng/mL) were investigated retrospectively. We measured total AFP and the percentage of AFP-L3 using a µTAS Wako i30 device. The possible presence of hepatocellular carcinoma (HCC) was thoroughly investigated by various examinations carried out from 1 month before to 1 month after measurements. In addition, hs-AFP-L3 elevated and non-elevated groups, divided by the cut-off value based on a receiver-operator characteristic (ROC) curve, were followed for possible future development of HCC.

RESULTS

hs-AFP-L3 was above the detectable range in 60 patients (24.9%). Among those AFP-L3 positive cases, 20 (33.3%) were found to be HCC prevalent, whereas HCC was found in just 16 patients (8.8%) with undetectable hs-AFP-L3 levels. We determined the cut-off value of hs-AFP-L3%, which shows the proportion of AFP L3 in total AFP, to be 5.75%. During the follow-up period, HCC was newly detected in six patients (22.2%) in the hs-AFP-L3% elevated group and in 10 (5.6%) in the non-elevated group. Analysis using the Kaplan-Meier method showed the HCC-free rate of the hs-AFP-L3% elevated group was significantly lower than that of the non-elevated group (P=0.0038). Independent predicting variants were female sex (P=0.0024) and hs-AFP-L3% elevation (P=0.0036).

CONCLUSION

Our results suggest hs-AFP-L3 level is a useful tumor marker for HCC in patients with CLD and low serum AFP concentration.

Clinical utility of highly sensitive Lens culinaris agglutinin-reactive alpha-fetoprotein in hepatocellular carcinoma patients with alpha-fetoprotein <20 ng/mL

The Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3) has been used as a diagnostic and prognostic marker of hepatocellular carcinoma (HCC). The analytical sensitivity of a conventional method for AFP-L3% is not sufficient in patients with a low AFP level. This study was performed to determine the clinical utility of a newly developed highly sensitive AFP-L3% (hs-AFP-L3%) assay in patients with an AFP level <20 ng/mL. In the cohort study, serum samples obtained from 270 patients with newly diagnosed HCC before treatment and 396 patients with chronic liver disease at Ogaki Municipal Hospital, in both of which the AFP level was <20 ng/mL, were measured for conventional AFP-L3% (c-AFP-L3%), hs-AFP-L3% and des-gamma-carboxy prothrombin (DCP). Diagnostic sensitivity and specificity of hs-AFP-L3% at a cut-off level of 5% were 41.5% and 85.1%, respectively, significantly increasing the sensitivity from 7.0% for c-AFP-L3%. Multivariate analysis identified hs-AFP-L3% as an independent factor associated with reduced long-term survival. The survival rate of patients with high hs-AFP-L3% (≥ 5%) before treatment was significantly poorer than that of patients with low hs-AFP-L3% (<5%) (P < 0.001). In patients with AFP <20 ng/mL, measurements of AFP-L3% by the highly sensitive method before treatment were more useful for diagnosis and prognosis of HCC than by the conventional method.

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.

Clinical advantage of highly sensitive on-chip immunoassay for fucosylated fraction of alpha-fetoprotein in patients with hepatocellular carcinoma

BACKGROUND

Alpha-fetoprotein (AFP) has been widely used as a diagnostic master for hepatocellular carcinoma (HCC), and the fucosylated fraction of AFP (AFP-L3) has been reported to be a specific marker for HCC. However, AFP-L3 has not always been reliable in cases with low serum AFP concentrations. Recently, a novel automated immunoassay for AFP-L3, the micro-total analysis system (μ-TAS), has been developed.

AIM

The aim of this study is to evaluate the clinical usefulness of μ-TAS AFP-L3.

METHODS

Serum AFP-L3 was measured in 295 patients with HCC and in 350 with benign liver diseases. The diagnostic accuracy of μ-TAS AFP-L3 was compared with that of the conventional assay (liquid-phase binding assay; LiBASys). The relationship between μ-TAS AFP-L3 and clinical features was investigated.

RESULTS

When the cutoff value was set at 7%, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of μ-TAS AFP-L3 were 60.0%, 90.3%, 76.4%, 83.9%, and 72.8%, respectively. Its sensitivity was particularly good (41.1%) in HCC subgroups with lower AFP concentrations (<20 ng/ml). The positivity rates for μ-TAS AFP-L3 were higher at each tumor stage than those of LiBASys AFP-L3 (μ-TAS/LiBASys: stage I, 44.2%/16.3%; stage II, 52.9%/37.5%; stage III, 66.4%/44.5%; stage IV, 82.8%/65.5%).

CONCLUSIONS

μ-TAS AFP-L3 is more sensitive for discriminating HCC than the conventional LiBASys AFP-L3, particularly in subgroups with lower AFP concentrations and early-stage HCC.

Fucosylated fraction of alpha-fetoprotein as a predictor of prognosis in patients with hepatocellular carcinoma after curative treatment

AIM

The aim of this study was to evaluate the clinical usefulness of measuring the Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3) for prognostic predictor in patients with hepatocellular carcinoma (HCC).

METHODS

A total of 477 HCC patients who underwent percutaneous ablative therapy or hepatectomy were enrolled. Overall survival and recurrence-free survival were respectively evaluated retrospectively and prospectively. Multivariate analyses of clinical prognostic factors were performed by Cox's stepwise proportional hazard model.

RESULTS

AFP-L3 status was a statistically significant independent prognostic factor of long-term survival (P = 0.013) and recurrence-free survival (P = 0.006) in patients who underwent percutaneous ablative therapy. In contrast, AFP-L3 did not affect prognosis in patients who underwent hepatectomy.

CONCLUSIONS

AFP-L3 had different impacts on prognosis in patients with HCC who underwent percutaneous ablative therapy and hepatectomy. Our results suggest that AFP-L3 positivity (>or=15%) might be a promising indicator for choosing therapeutic modalities in HCC patients.

A new prognostic staging system for hepatocellular carcinoma: value of the biomarker combined Japan integrated staging score

OBJECTIVES

The Japan Integrated Staging (JIS) score has been reported to have good stratification ability in patients with hepatocellular carcinoma (HCC). However, the JIS score could not estimate malignant grade of HCC. The aim of this study was to evaluate the performance of a new staging system: the biomarker combined JIS (bm-JIS) which includes three tumor markers: alpha-fetoprotein (AFP), Lens culinaris agglutinin-reactive AFP and des-gamma-carboxy prothrombin with the conventional JIS score.

METHODS

A total of 1,924 HCC patients were included in this study. We compared their overall survival, the stratification ability and suitability as a prognostic model according to the bm-JIS score and the conventional JIS score.

RESULTS

There were significant differences between the survival curves for all bm-JIS scores. For the conventional JIS scores of 0, 1, 2 and 3, the survival curves differed greatly according to the bm-JIS score (p < 0.0001). The independent homogenizing ability and the stratification value of the JIS score and the bm-JIS score determined by the likelihood ratio test using the Cox proportional hazard regression model showed the bm-JIS score to have a higher value(chi2 = 717.348) than the JIS score (chi2 = 668.91).

CONCLUSIONS

The bm-JIS score showed superior stratification ability and thus was found to be a better predictor of the prognosis than the conventional JIS score, especially for the patients with good prognosis.