Assessment of the Clinical Utility of Glypican 3 as a Serum Marker for the Diagnosis of Hepatocellular Carcinoma

Experimental Validation of Novel Glypican 3 Exosomes for the Detection of Hepatocellular Carcinoma in Liver Cirrhosis

BACKGROUND AND AIMS

Hepatocellular carcinoma (HCC) developing in the context of preexisting cirrhosis is characterized by impaired autophagy that results in increased exosome release. This study was conducted to determine whether circulating exosomes expressing glypican 3 (GPC3) could be utilized as a biomarker for HCC detection and treatment response in patients with cirrhosis.

METHODS

Immunohistochemistry was performed to assess p62 and GPC3 expression in the lesion and adjacent tissue from cirrhosis with HCC. GPC3-enriched exosomes were captured by an enzyme-linked immunosorbent assay (ELISA). The diagnostic specificity of serum exosome-derived GPC3 (eGPC3) was determined using samples obtained from malignancy-free controls, malignancy-free cirrhotics, cirrhotics with confirmed HCC, and patients with a non-HCC malignancy. The performance of eGPC3 was validated using serum samples of HCC patients received chemotherapy.

RESULTS

We found that the expression of p62 and GPC3 was significantly increased in HCC tissues compared to adjacent cirrhotic liver. Impaired autophagy and exosome shedding were confirmed in HCC cell lines. Mass spectroscopic analysis revealed that GPC3 was enriched in exosomes isolated from HCC cell lines. An affinity ELISA assay was developed that specifically captures GPC3 positive exosomes in the serum. Total exosome concentration and eGPC3 were significantly elevated in cirrhotic patients with HCC as compared to the reference control groups. Furthermore, decreases in post-treatment exosome concentration and eGPC3 levels were more closely correlated with response to locoregional chemotherapy compared to change in serum AFP in HCC patients awaiting liver transplantation.

CONCLUSION

We developed an affinity exosome capture assay to detect GPC3 enriched exosomes. Our preliminary assessment shows that GPC3 positive exosomes can be used for HCC detection and prediction of treatment outcomes.

Involvement of Kynurenine Pathway in Hepatocellular Carcinoma

Simple Summary

The kynurenine pathway (KP) is a biochemical pathway that synthesizes the vital coenzyme, nicotinamide adenine dinucleotide (NAD⁺). In cancer, the KP is significantly activated, leading to tryptophan depletion and the production of downstream metabolites, which skews the immune response towards tumour tolerance. More specifically, advanced stage cancers that readily metastasize evidence the most dysregulation in KP enzymes, providing a clear link between the KP and cancer morbidity. Consequently, this provides the rationale for an attractive new drug discovery opportunity for adjuvant therapeutics targeting KP-mediated immune tolerance, which would greatly complement current pharmacological interventions. In this review, we summarize recent developments in the roles of the KP and clinical trials examining KP inhibition in liver cancer.

Abstract

As the second and third leading cancer-related death in men and the world, respectively, primary liver cancer remains a major concern to human health. Despite advances in diagnostic technology, patients with primary liver cancer are often diagnosed at an advanced stage. Treatment options for patients with advanced hepatocarcinoma (HCC) are limited to systemic treatment with multikinase inhibitors and immunotherapy. Furthermore, the 5-year survival rate for these late-stage HCC patients is approximately 12% worldwide. There is an unmet need to identify novel treatment options and/or sensitive blood-based biomarker(s) to detect this cancer at an early stage. Given that the liver harbours the largest proportion of immune cells in the human body, understanding the tumour–immune microenvironment has gained increasing attention as a potential target to treat cancer. The kynurenine pathway (KP) has been proposed to be one of the key mechanisms used by the tumour cells to escape immune surveillance for proliferation and metastasis. In an inflammatory environment such as cancer, the KP is elevated, suppressing local immune cell populations and enhancing tumour growth. In this review, we collectively describe the roles of the KP in cancer and provide information on the latest research into the KP in primary liver cancer.

Proteome Analysis of Urinary Biomarkers in Acute Hypercoagulable State Rat Model

Thrombotic diseases are usually preceded by a hypercoagulable state in the body. This study aimed to screen potential urinary biomarkers for hypercoagulable state based on proteome analysis. Wistar rats were administered with the hemostatic agent etamsylate to establish hypercoagulable state. Urine samples were collected for proteome analysis. We found 20 proteins with levels more than 1.5-fold in difference between control rats and model rats. We searched human homologs of 20 rat proteins and identified 13 human proteins. Of the 13 human homologous proteins, nine were members of human core urinary proteome. Human homologous proteins of differential proteins were highly expressed in 31 human tissues, especially in the kidneys followed by digestive system and reproductive system. Surprisingly, we did not identify known coagulation factors as differential proteins in the urine of model rats. Hypercoagulable state of the body may not involve direct changes in coagulation factors but causes the changes upstream of the coagulation cascade system. Common differential urinary proteins between different hypercoagulable states suggest some common pathways in the formation of hypercoagulable states and may serve as potential biomarkers for the prevention and treatment of thrombotic diseases.

Proteomic Profiling and Artificial Intelligence for Hepatocellular Carcinoma Translational Medicine

Hepatocellular carcinoma (HCC) is the most common primary cancer of the liver with high morbidity and mortality rates worldwide. Since 1963, when alpha-fetoprotein (AFP) was discovered as a first HCC serum biomarker, several other protein biomarkers have been identified and introduced into clinical practice. However, insufficient specificity and sensitivity of these biomarkers dictate the necessity of novel biomarker discovery. Remarkable advancements in integrated multiomics technologies for the identification of gene expression and protein or metabolite distribution patterns can facilitate rising to this challenge. Current multiomics technologies lead to the accumulation of a huge amount of data, which requires clustering and finding correlations between various datasets and developing predictive models for data filtering, pre-processing, and reducing dimensionality. Artificial intelligence (AI) technologies have an enormous potential to overcome accelerated data growth, complexity, and heterogeneity within and across data sources. Our review focuses on the recent progress in integrative proteomic profiling strategies and their usage in combination with machine learning and deep learning technologies for the discovery of novel biomarker candidates for HCC early diagnosis and prognosis. We discuss conventional and promising proteomic biomarkers of HCC such as AFP, lens culinaris agglutinin (LCA)-reactive L3 glycoform of AFP (AFP-L3), des-gamma-carboxyprothrombin (DCP), osteopontin (OPN), glypican-3 (GPC3), dickkopf-1 (DKK1), midkine (MDK), and squamous cell carcinoma antigen (SCCA) and highlight their functional significance including the involvement in cell signaling such as Wnt/β-catenin, PI3K/Akt, integrin αvβ3/NF-κB/HIF-1α, JAK/STAT3 and MAPK/ERK-mediated pathways dysregulated in HCC. We show that currently available computational platforms for big data analysis and AI technologies can both enhance proteomic profiling and improve imaging techniques to enhance the translational application of proteomics data into precision medicine.

Alpha-Fetoprotein, Protein Induced by Vitamin K Absence or Antagonist II and Glypican-3 for the Detection and Prediction of Hepatocellular Carcinoma in Patients with Cirrhosis of Viral Etiology

International guidelines recommend the use of ultrasound as a surveillance tool for hepatocellular carcinoma (HCC) in patients with cirrhosis, while the role of serum biomarkers is still debated. We investigated serum alpha-fetoprotein (AFP), protein induced by vitamin K absence or antagonist II (PIVKA-II) and glypican-3 (GPC-3) diagnostic accuracy for HCC detection and prediction in patients with liver cirrhosis of viral etiology under surveillance. A total of 349 patients (200 cirrhosis and 149 HCC) were enrolled. The 200 patients with cirrhosis consisted of 114 patients still HCC-free after 36 months of follow-up and 86 patients that developed HCC after 13.8 (11.0-19.8) months. AFP, PIVKA-II and GPC-3 were measured in serum samples collected at tumor diagnosis in the 149 patients with HCC, and at the beginning of follow-up in the 200 patients with cirrhosis. The higher performance for HCC detection was observed for PIVKA-II (area under the curve (AUC) = 0.790), followed by AFP (AUC = 0.737) and GPC-3 (AUC = 0.637); the combination of AFP + PIVKA-II improved the diagnostic accuracy to AUC = 0.822. Serum PIVKA-II values, but not AFP and GPC-3, were significantly higher in the 86 cirrhotics that developed HCC compared with the 114 cirrhotics still HCC-free after 36 months of follow-up (p = 0.020). PIVKA-II ≥ 55 mAU/mL allowed to identify patients with cirrhosis at higher risk of HCC development (Log-rank test, p < 0.001; adjusted Hazard Ratio = 1.99, p = 0.001). In conclusion, the measurement of PIVKA-II in patients with cirrhosis may be useful to tailor personalized surveillance strategies.

Diagnostic value of serum glypican-3 alone and in combination with AFP as an aid in the diagnosis of liver cancer

BACKGROUND

Recently, a series of studies have been published to examine the possible diagnostic and prognostic values of glypican-3 (GPC3) in liver cancer with conflicting results observed. Thus, the present study aimed to assess the values of preoperative serum GPC3 alone and in combination with AFP for the diagnosis of liver cancer.

METHODS

An enzyme-linked immunoassay was used to quantify serum GPC3 in hepatocellular carcinoma group (HCC, n = 210), intrahepatic cholangiocarcinoma group (ICC, n = 36), combined hepatocellular cholangiocarcinoma group (cHCC-CC, n = 8), metastatic liver cancer group (MLC, n = 10) and normal controls (NC, n = 134).

RESULTS

The area under the curve (AUC) of GPC3 for HCC versus NC was 0.879, with a sensitivity of 79.52% at an optimal cutoff value of 0.0414 ng/mL; when GPC3 was combined with AFP, the AUC and sensitivity were increased to 0.925 and 88.10%, respectively. In addition, 43 of 68 AFP-negative patients had elevated GPC3 levels. Furthermore, the positive rate of GPC3 was significantly higher than the that of AFP for HCC in early stage.

CONCLUSIONS

Serum GPC3 was superior to AFP for the diagnosis of early-stage HCC, and may be complementary to AFP for distinguishing HCC from NC.

Plasma and tumoral glypican-3 levels are correlated in patients with hepatitis C virus-related hepatocellular carcinoma

Glypican-3 (GPC3) is a cancer antigen expressed in approximately 80% of hepatocellular carcinomas (HCC) and is secreted into the blood. To confirm the effectiveness of GPC3 as a biomarker in HCC, we analyzed the relationship between GPC3 expression levels in cancer cells and in blood in 56 patients with HCC. Preoperative plasma GPC3 levels were determined with an immunoassay, and expression of GPC3 in resected tumors was analyzed by immunohistochemical staining. Median plasma GPC3 level in all HCC cases was 4.6 pg/mL, and tended to be higher in patients with hepatitis C virus (HCV)-related HCC (HCV group) (9.9 pg/mL) than in patients with hepatitis B virus (HBV)-related HCC (HBV group) (2.6 pg/mL) or in those without virus infection (None group) (3.0 pg/mL), suggesting that the virus type most likely influences GPC3 secretion. Median percentage of GPC3+ cells in tumors was also higher in the HCV (26.2%) and HBV (11.1%) groups than in the None group (4.2%). In the HCV group, there was a positive correlation between the two parameters (r = 0.66, P < .01). Moreover, receiver operating characteristic analysis predicted >10% GPC3+ cells in a tumor if the cut-off value was 6.8 pg/mL (sensitivity 80%, specificity 100%; area under the curve 0.875, 95% confidence interval 0.726-1) in the HCV group. Plasma concentration of GPC3 could be a predictive marker of tumoral GPC3 expression in patients with HCV-related HCC, suggesting a useful biomarker for immunotherapies targeting GPC3, although larger-scale validations are needed.

Study on Diagnostic Values of Astrocyte Elevated Gene 1 (AEG-1) and Glypican 3 (GPC-3) in Hepatocellular Carcinoma

OBJECTIVES

To investigate the diagnostic potential of AEG-1 and GPC-3 in hepatocellular carcinoma (HCC).

METHODS

AEG-1 and GPC-3 immunohistochemistry were performed on HCC, adjacent nontumor tissue (ANT), and dysplastic nodules (DN).

RESULTS

H score of AEG-1 or GPC-3 in HCC was significantly higher than in ANT or DN. In HCC, 92% and 54% showed AEG-1 and GPC-3 positivity, respectively. In ANT, 16.2% were AEG-1 and 7.6% GPC-3 positive. AEG-1 staining was mostly diffuse, whereas GPC-3 frequently showed focal staining. AEG-1 alone showed high sensitivity but low specificity and accuracy. GPC-3, on the other hand, showed high specificity but low sensitivity and accuracy. Combination of both stains boosted the sensitivity, specificity, and accuracy to 94.6%, 89.5%, and 90.5%, respectively, when only diffuse staining was considered as positive.

CONCLUSIONS

AEG-1 or GPC-3 alone seemed not an ideal marker for HCC. The combination of AEG-1 and GPC-3 might improve early diagnosis of HCC.

rs2267531, a promoter SNP within glypican-3 gene in the X chromosome, is associated with hepatocellular carcinoma in Egyptians

Hepatocellular carcinoma (HCC) is a major health concern in Egypt owing to the high prevalence of hepatitis C virus (HCV) infection. HCC incidence is characterized by obvious male predominance, yet the molecular mechanisms behind this gender bias are still unidentified. Functional variations in X-linked genes have more impact on males than females. Glypican-3 (GPC3) gene, located in the Xq26 region, has lately emerged as being potentially implicated in hepatocellular carcinogenesis. The current study was designed to examine the association of -784 G/C single nucleotide polymorphism (SNP) in GPC3 promoter region (rs2267531) with HCC susceptibility in male and female Egyptian HCV patients. Our results revealed a significant association between GPC3 and HCC risk in both males and females, evidenced by higher C allele and CC/C genotype frequencies in HCC patients when compared to controls. However, no such association was found when comparing HCV patients to controls. Moreover, GPC3 gene and protein expression levels were significantly higher in CC/C than in GG/G genotype carriers in males and females. The CC/C genotype exhibited a significant shorter overall survival than GG/G genotype in HCC patients. In conclusion, GPC3 rs2267531 on the X chromosome is significantly associated with HCC, but not with HCV infection, in the Egyptian population.

Performance of Serum Glypican 3 in Diagnosis of Hepatocellular Carcinoma: A meta-analysis

INTRODUCTION AND AIM

Serum glypican-3 (GPC3) has been explored as a non-invasive biomarker of hepatocellular carcinoma (HCC). However, controversy remains on its diagnostic accuracy. Therefore, we aimed to conduct a systematic review and metaanalysis to evaluate the differential diagnostic accuracy of serum GPC3 between HCC and liver cirrhosis (LC) cases.

MATERIAL AND METHODS

After the strict filtering and screening of studies from NCBI, PUBMED, Clinical Trials, Cochrane library, Embase, Prospero and Web of Science databases, 11 studies were selected. All studies provided the sensitivity and specificity of GPC3 and the alpha-fetoprotein (AFP) in the HCC and LC diagnosis. The sensitivity and specificity, and the area under the receiver operating characteristic curve (AUC) were determined and compared between GPC3 and AFP, which was set as a positive control.

RESULTS

Pooled sensitivity (95% CI) and specificity (95% CI) were 0.55 (0.52-0.58) and 0.58 (0.54-0.61) for GPC3, 0.54 (0.51-0.57) and 0.83 (0.80-0.85) for AFP, and 0.85 (0.81-0.89) and 0.79 (0.73-0.84) for GPC3 + AFP, respectively. The AUCs of GPC3, AFP and GPC3 + AfP were 0.7793, 0.7867 and 0.9366, respectively. GPC3 had a nearly similar sensitivity as AFP, while the specificity and AUC of GPC3 was lower than that of AFP. The combination of GPC3 and AFP yielded a better sensitivity and AUC than GPC3 or AFP.

CONCLUSION

Serum GPC3 is inferior to AFP in the differential diagnosis between HCC and LC. However, the combination of GPC3 and AFP exhibited a much better performance.

Diagnosis accuracy of serum glypican-3 level in patients with hepatocellular carcinoma: a systematic review with meta-analysis

BACKGROUND

Previous studies have evaluated the diagnostic value of serum glypican-3 in patients with hepatocellular carcinoma. However, the results remain inconsistent and even controversial. Thus, the aim of the present meta-analysis was to clarify the diagnostic accuracy of serum glypican-3 for hepatocellular carcinoma.

METHODS

A meta-analysis including 22 studies was performed with 2325 cases and 2280 controls. Relevant studies were searched in the EMBASE, PubMed, and Web of Science databases, covering relevant papers published until November 1, 2017. The quality of the studies was assessed by revised QUADAS tools. Sensitivity, specificity, and other measures were pooled and determined to evaluate the accuracy of serum glypican-3 in the diagnosis of hepatocellular carcinoma by random-effects models. Summary receiver operating characteristic curve (sROC) analysis was performed to summarize the overall test performance.

RESULTS

The results showed that the pooled overall diagnostic sensitivity, specificity, and 95% confidence interval (CI) for serum glypican-3 in the diagnosis of hepatocellular carcinoma were 68% (56-79%) and 92% (82-96.0%), respectively. Besides, the summary diagnostic odds ratio and 95% CI for glypican-3 were 23.53 (8.57-64.63). In addition, the area under sROC and 95% CI was 0.87 (0.84-0.90). The major design deficiencies of included studies were differential verification bias, and a lack of clear exclusion and inclusion criteria.

CONCLUSIONS

The results of this meta-analysis suggested that serum glypican-3 was acceptable as a moderate diagnostic marker in the diagnosis of hepatocellular carcinoma compared with healthy individuals, which could elevate the sensitivity and specificity of diagnosis. Furthermore, more well-designed studies with large sample sizes are needed to show the effectiveness of glypican-3 in the differential diagnosis of hepatocellular carcinoma.

Glypican-3 induces oncogenicity by preventing IGF-1R degradation, a process that can be blocked by Grb10

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and is a major cause of cancer-related death worldwide. Previously, we demonstrated that glypican-3 (GPC3) is highly expressed in HCC, and that GPC3 induces oncogenicity and promotes the growth of cancer cells through IGF-1 receptor (IGF-1R). In the present study, we investigated the mechanisms of GPC3-mediated enhancement of IGF-1R signaling. We demonstrated that GPC3 decreased IGF-1-induced IGF-1R ubiquitination and degradation and increased c-Myc protein levels. GPC3 bound to Grb10, a mediator of ligand-induced receptor ubiquitination, and the overexpression of Grb10 blocked GPC3-enhanced IGF-1-induced ERK phosphorylation. GPC3 promoted the growth of NIH3T3 and PLC-PRF-5 cells in serum-free medium but did not promote the growth of IGF-1R negative R- cells. Grb10 overexpression decreased GPC3-promoted cell growth. Therefore, the present study elucidates the mechanisms of GPC3-induced oncogenicity, which may highlight new strategies for the treatment of HCC.

Glypican-3: A promising biomarker for hepatocellular carcinoma diagnosis and treatment

Liver cancer is the second leading cause of cancer-related deaths, and hepatocellular carcinoma (HCC) is the most common type. Therefore, molecular targets are urgently required for the early detection of HCC and the development of novel therapeutic approaches. Glypican-3 (GPC3), an oncofetal proteoglycan anchored to the cell membrane, is normally detected in the fetal liver but not in the healthy adult liver. However, in HCC patients, GPC3 is overexpressed at both the gene and protein levels, and its expression predicts a poor prognosis. Mechanistic studies have revealed that GPC3 functions in HCC progression by binding to molecules such as Wnt signaling proteins and growth factors. Moreover, GPC3 has been used as a target for molecular imaging and therapeutic intervention in HCC. To date, GPC3-targeted magnetic resonance imaging, positron emission tomography, and near-infrared imaging have been investigated for early HCC detection, and various immunotherapeutic protocols targeting GPC3 have been developed, including the use of humanized anti-GPC3 cytotoxic antibodies, treatment with peptide/DNA vaccines, immunotoxin therapies, and genetic therapies. In this review, we summarize the current knowledge regarding the structure, function, and biology of GPC3 with a focus on its clinical potential as a diagnostic molecule and a therapeutic target in HCC immunotherapy.

Glypican 3 as a Serum Marker for Hepatoblastoma

Hepatoblastoma (HB) is the most common primary liver cancer in children. The conventional serum marker for HB, alpha-fetoprotein (AFP), has its limitations. Novel serum markers need to be explored. Glypican 3 (GPC3) has been reported to be an excellent histological immunomarker for HB. However, the clinical value of serum GPC3 in patients with HB is unknown. A total of 184 serum samples were tested for both GPC3 by ELISA, and AFP by immunometric assay. Of these, 134 were from 32 patients with HB at three treatment stages, 30 from age-matched patients with benign hepatobiliary disorders (BHD) and 20 from age-matched "normal controls"(NC). We found that the GPC3 levels in HB pretreatment group were significantly higher than those in NC group and HB remission group but not statistically different from those in BHD group and HB during treatment group. In contrast, AFP showed significant differences among different groups. The areas under the receiver operating curve (AUROC) value, sensitivity and specificity of GPC3 for HB pretreatment group versus all controls were all significantly lower than those of AFP. Serum GPC3 levels were not associated with prognostic parameters. We concluded that GPC3 is inferior to AFP as a serum marker for HB.

GPC-HCC model: a combination of glybican-3 with other routine parameters improves the diagnostic efficacy in hepatocellular carcinoma

Conflicting results for circulating glypican-3 (GPC3) were reported in hepatocellular carcinoma (HCC) diagnosis. We aimed to improve the diagnostic power of GPC3 by developing a GPC-HCC model for diagnosing HCC. GPC3 was tested for HCC (138), liver cirrhosis (56), and fibrosis (62) patients by ELISA. Data from patient groups were retrospectively analyzed. A novel score, GPC-HCC, based on combination of GPC3 and routine laboratory tests, was developed for HCC diagnosis. The GPC-HCC model values produced a significant 1.7-fold increase in liver cirrhosis and 3.2-fold increase in HCC, in comparison with liver fibrosis. In contrast to GPC3 and alpha fetoprotein (AFP), the GPC-HCC model showed high HCC diagnostic power with area under the curve (AUC) of 0.939, sensitivity 93 %, specificity 93 %, positive predictive value 89 %, negative predictive value 95 %, and efficiency 93 %. GPC-HCC AUC in HCC with single tumor, absent vascular invasion, and tumor size ≤3 cm were 0.93, 0.92, and 0.92, respectively, compared with 0.63, 0.63, and 0.64, respectively, for GPC3 and 0.69, 0.70, 0.55, respectively, for AFP. In conclusion, owing to these promising findings, the combination of GPC3 with other laboratory simple routine tests (GPC-HCC model) could improve the diagnostic power of GPC3 in HCC screening and follow up of cirrhotic patients.