Expression of oncofetal antigen glypican-3 associates significantly with poor prognosis in HBV-related hepatocellular carcinoma

Early monitoring values of oncogenic signalling molecules for hepatocellular carcinoma

The prevention and early diagnosis of liver cancer remains a global medical challenge. During the malignant transformation of hepatocytes, a variety of oncogenic cellular signalling molecules, such as novel high mobility group-Box 3, angiopoietin-2, Golgi protein 73, glypican-3, Wnt3a (a signalling molecule in the Wnt/β-catenin pathway), and secretory clusterin, can be expressed and secreted into the blood. These signalling molecules are derived from different signalling pathways and may not only participate in the malignant transformation of hepatocytes but also become early diagnostic indicators of hepatocarcinogenesis or specific targeted molecules for hepatocellular carcinoma therapy. This article reviews recent progress in the study of several signalling molecules as sensitive biomarkers for monitoring hepatocarcinogenesis.

Early monitoring values of oncogenic signalling molecules for hepatocellular carcinoma

The prevention and early diagnosis of liver cancer remains a global medical challenge. During the malignant transformation of hepatocytes, a variety of oncogenic cellular signalling molecules, such as novel high mobility group-Box 3, angiopoietin-2, Golgi protein 73, glypican-3, Wnt3a (a signalling molecule in the Wnt/β-catenin pathway), and secretory clusterin, can be expressed and secreted into the blood. These signalling molecules are derived from different signalling pathways and may not only participate in the malignant transformation of hepatocytes but also become early diagnostic indicators of hepatocarcinogenesis or specific targeted molecules for hepatocellular carcinoma therapy. This article reviews recent progress in the study of several signalling molecules as sensitive biomarkers for monitoring hepatocarcinogenesis.

Serum glypican-3 for the prediction of survival in patients with hepatocellular carcinoma

BACKGROUND

Glypican-3 (GPC-3) is a heparan sulfate proteoglycan overexpressed by hepatocellular carcinoma (HCC) cells. Several studies highlighted the diagnostic and prognostic value of GPC-3 expression in liver tissue, while data on the reliability of serum GPC-3 are limited and conflicting. We aimed to evaluate the prognostic value of serum GPC-3 in patients with HCC.

METHODS

A total of 449 patients (91 F and 358 M; median age 65 [38-86] years) with a new diagnosis of HCC and available serum samples collected at tumor diagnosis were retrospectively analyzed. All patients had cirrhosis and the main underlying etiology was viral (N.=323, 72%). Barcelona Clinic Liver Cancer (BCLC) staging system was adopted for patients' classification (BCLC 0/A, N.=293, 65% vs. B/C/D, N.=156, 35%) and treatment allocation. Response to therapy was assessed by modified Response Evaluation Criteria in Solid Tumors (mRECIST).

RESULTS

Median overall survival (OS) after HCC diagnosis was 30 months (95% confidence interval [CI]: 27-34). Patients with serum GPC-3>150 pg/mL showed lower overall survival (16; 95%CI: 13-24 months) compared to those with GPC-3≤150 pg/mL (36; 95%CI: 30-56 months) (Log-rank test, P<0.001). At multivariate Cox proportional-hazard regression analysis, presence of ascites (adjusted Hazard Ratio [aHR]=1.84; 95%CI: 1.23-2.74, P=0.003), BCLC stage (aHR=1.65; 95%CI: 1.39-1.97, P<0.001), mRECIST (aHR=0.33; 95%CI: 0.21-0.51, P<0.001) and GPC-3>150 pg/mL (aHR=2.02; 95%CI: 1.47-2.78, P<0.001) resulted significantly associated to overall survival.

CONCLUSIONS

Serum GPC-3 resulted an independent prognostic factor for patients with HCC irrespectively from tumor stage and response to therapy.

Diagnostic accuracy and prognostic significance of Glypican-3 in hepatocellular carcinoma: A systematic review and meta-analysis

Purpose

Glypican-3 (GPC-3) expression is abnormal in the occurrence and development of hepatocellular carcinoma (HCC). To explore whether GPC-3 has diagnostic accuracy and prognostic significance of HCC, we did a systematic review and meta-analysis.

Method

PubMed, Embase, Cochrane Library, and China National Knowledge Infrastructure were searched with keywords “GPC-3” and “HCC” and their MeSH terms from inception to July 2022. We applied the hierarchical summary receiver operating characteristic model and evaluated the diagnostic value of GPC-3 alone and combination, and the correlation between high and low GPC-3 expression on clinicopathological features and survival data in prognosis.

Results

Forty-one original publications with 6,305 participants were included, with 25 of them providing data for diagnostic value and 18 records were eligible for providing prognostic value of GPC-3. GPC-3 alone got good diagnostic value in patients with HCC when compared with healthy control and moderate diagnostic value when compared with patients with cirrhosis. In addition, combination of GPC-3 + AFP and GPC-3 + GP73 got great diagnostic value in HCC versus cirrhosis groups; the combination of GPC-3 can also improve the diagnostic accuracy of biomarkers. Moreover, we discovered that overexpression of GPC-3 was more likely found in HBV infection, late tumor stage, and microvascular invasion groups and causes shorter overall survival and disease free survival, which means poor prognosis.

Conclusion

GCP-3 could be used as a biomarker in HCC diagnosis and prognosis, especially in evaluated diagnostic value in combination with AFP or GP73, and in forecasting worse survival data of overexpression GPC-3

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier [CRD42022351566].

Construction and validation of a predictive model for hepatocellular carcinoma based on serum markers

Background

Early hepatocellular carcinoma (HCC) detection with non-invasive biomarkers remains an unmet clinical need. We aimed to construct a predictive model based on the pre-diagnostic levels of serum markers to predict the early-stage onset of HCC.

Methods

A total of 339 HCC patients (including 157 patients from Changzhou cohort and 182 patients from Wuxi cohort) were enrolled in our retrospective study. Levels of 25 baseline serum markers were collected. Propensity score matching (PSM) analysis was conducted to balance the distributions of patients’ gender, age, and the surveillance time between HCC group and control group. Then, Receiver operating characteristic (ROC) and Logistic regression analysis were performed to screen the independent predictive variables and construct a non-invasive predictive model. Subsequently, ROC curve and Kaplan–Meier (K–M) curve were used to evaluate the predictive values of the model. Clinical net benefit of the model was demonstrated by decision curve analysis (DCA) and clinical impact curve.

Results

Five independent predictive variables for HCC onset and two general characteristics of patients (age and gender) were incorporated into the score model. ROC and DCA curves showed that the score model had better predictive performance in discrimination and clinical net benefit compared with single variable or other score systems, with the area under the curve (AUC) of 0.890 (95% CI 0.856–0.925) in Changzhou cohort and 0.799 (95% CI 0.751–0.849) in Wuxi cohort. Meanwhile, stratification analysis indicated that the score model had good predictive values for patients with early tumor stage (AJCC stage I) or small tumors (< 2 cm). Moreover, the score of HCC patient began to increase at 30 months before clinical diagnosis and reach a peak at 6 months.

Conclusion

Based on this model, we could optimize the current risk stratification at an early stage and consider further intensive surveillance programs for high-risk patients. It could also help clinicians to evaluate the progression and predict the prognosis of HCC patients.

Combining therapeutic vaccines with chemo- and immunotherapies in the treatment of cancer

INTRODUCTION

Breakthroughs in cancer immunotherapy have spurred interest in the development of vaccines to mediate prophylactic protection and therapeutic efficacy against primary tumors or to prevent relapse. However, immunosuppressive mechanisms employed by cancer cells to generate effective resistance have hampered clinical translation of therapeutic cancer vaccines. To enhance vaccine efficacy, the immunomodulatory properties of cytoreductive therapies could amplify a cancer-specific immune response.

AREAS COVERED

Herein, the authors discuss therapeutic cancer vaccines that harness whole cells and antigen-targeted vaccines. First, recent advancements in both autologous and allogeneic whole-cell vaccines and combinations with checkpoint blockade and chemotherapy are reviewed. Next, tumor antigen-targeted vaccines using peptide-based vaccines and DNA-vaccines are discussed. Finally, combination therapies using antigen-targeted vaccines are reviewed.

EXPERT OPINION

A deeper understanding of the immunostimulatory properties of cytoreductive therapies has supported their utility in combination therapies involving cancer vaccines as a potential strategy to induce a durable anti-tumor immune response for multiple types of cancers. Based on current evidence, combination therapies may have synergies that depend on the identity of the cytotoxic agent, vaccine target, dosing schedule, and cancer type. Together, these observations suggest that combining cancer vaccines with immunomodulatory cytoreductive therapy is a promising strategy for cancer therapy.

Evaluation for clinical and prognostic implications of glypican-3 and α-fetoprotein in hepatocellular carcinoma: a new subtype?

Background

In this retrospective study, we investigated clinicopathological features and prognosis of hepatocellular carcinoma (HCC) patients applying an immunosubtyping method based on the serum α-fetoprotein (AFP) levels and glypican-3 (GPC3) immunohistochemical expression.

Methods

Two hundred and twenty-nine HCC patients, who had been subjected to hepatectomy and accepted serum AFP and GPC immunohistochemical expression tests, were divided into four groups: AFP⁺GPC3⁺, AFP⁺GPC3^–, AFP^–GPC3⁺, and AFP^–GPC3^– groups. During the study, HCC patients’ sex ratios, ages, incidence of cirrhosis, clinicopathological features—such as tumor lesion, tumor size, histological grade, vascular invasion, regional lymph node involvement, distant metastasis—and their follow-up time were observed and continuously recorded.

Results

Regarding their clinicopathological features, the four groups only differed in the histological grade with statistical significance. Furthermore, the four subtypes showed statistically significant differences in sex ratios and incidence of cirrhosis. Among the four subtypes, the prognosis was just statistically different between the AFP⁺GPC3⁺ and AFP^–GPC3⁺ groups, and AFP^–GPC3⁺ was associated with a better prognosis.

Conclusions

A new HCC subtype could guide the personalized therapy of HCC patients to a certain extent. The four different subtypes resulting from the AFP- and GPC3-based subclassification of HCC, especially for AFP⁺GPC3⁺ and AFP⁻GPC3⁻ groups, were meaningful prognostic markers for HCC.

Glypican-3: A New Target for Diagnosis and Treatment of Hepatocellular Carcinoma

Liver cancer is the second leading cause of cancer-related deaths worldwide, and hepatocellular carcinoma is the most common type. The pathogenesis of hepatocellular carcinoma is concealed, its progress is rapid, its prognosis is poor, and the mortality rate is high. Therefore, novel molecular targets for hepatocellular carcinoma early diagnosis and development of targeted therapy are critically needed. Glypican-3, a cell-surface glycoproteins in which heparan sulfate glycosaminoglycan chains are covalently linked to a protein core, is overexpressed in HCC tissues but not in the healthy adult liver. Thus, Glypican-3 is becoming a promising candidate for liver cancer diagnosis and immunotherapy. Up to now, Glypican-3 has been a reliable immunohistochemical marker for hepatocellular carcinoma diagnosis, and soluble Glypican-3 in serum has becoming a promising marker for liquid biopsy. Moreover, various immunotherapies targeting Glypican-3 have been developed, including Glypican-3 vaccines, anti- Glypican-3 immunotoxin and chimeric-antigen-receptor modified cells. In this review, we summarize and analyze the structure and physicochemical properties of Glypican-3 molecules, then review their biological functions and applications in clinical diagnosis, and explore the diagnosis and treatment strategies based on Glypican-3.

Yttrium-90-Labeled Anti-Glypican 3 Radioimmunotherapy Halts Tumor Growth in an Orthotopic Xenograft Model of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the second most lethal malignancy globally and is increasing in incidence in the United States. Unfortunately, there are few effective systemic treatment options, particularly for disseminated disease. Glypican-3 (GPC3) is a proteoglycan cell surface receptor overexpressed in most HCCs and provides a unique target for molecular therapies. We have previously demonstrated that PET imaging using a 89Zr-conjugated monoclonal anti-GPC3 antibody (αGPC3) can bind to minute tumors and allow imaging with high sensitivity and specificity in an orthotopic xenograft mouse model of HCC and that serum alpha-fetoprotein (AFP) levels are highly correlated with tumor size in this model. In the present study, we conjugated 90Y, a high-energy beta-particle-emitting radionuclide, to our αGPC3 antibody to develop a novel antibody-directed radiotherapeutic approach for HCC. Luciferase-expressing HepG2 human hepatoblastoma cells were orthotopically implanted in the livers of athymic nude mice, and tumor establishment was verified at 6 weeks after implantation by bioluminescent imaging and serum AFP concentration. Tumor burden by bioluminescence and serum AFP concentration was highly correlated in our model. Yttrium-90 was conjugated to αGPC3 using the chelating agent 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) and injected via the tail vein into the experimental mice at a dose of 200 μCi/mouse or 300 μCi/mouse. Control mice received DOTA-αGPC3 without radionuclide. At 30 days after a single dose of the radioimmunotherapy agent, mean serum AFP levels in control animals increased dramatically, while animals treated with 200 μCi only experienced a minor increase, indicating cessation of tumor growth, and animals treated with 300 μCi experienced a reduction in serum AFP concentration, indicating tumor shrinkage. Mean tumor-bearing liver weight in control animals was also significantly greater than that in animals that received either dose of 90Y-αGPC3. These results were achieved without significant toxicity as measured by body condition scoring and body weight. The results of this preclinical pilot demonstrate that GPC3 can be used as a target for radioimmunotherapy in an orthotopic mouse model of HCC and may be a target of clinical significance, particularly for disseminated HCC.

Meta-analysis and systematic review of prognostic significance of Glypican-3 in patients with hepatitis B-related hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common malignant cancer and the second cause of cancer-related death worldwide. Glypican-3 (GPC3) is established as an important prognostic factor for HCC but the results are still controversial. Moreover, its utility as an immunohistochemical marker for HCC is not conclusive. Herein we aimed to find the prognostic significance of GPC3 in HCC patients. The PubMed, Web of Science, EMBASE, SCOPUS and Cochrane library databases were searched and eligible studies based on the GPC3 expression and survival outcome of HCC (odds ratios or hazard ratios) included in the current meta-analysis. The STATA 12.0 and RevMan 5.3 software were used for statistical evaluations. 17 articles contained 2618 patients, were included in the recent meta-analysis. Our findings revealed a significant association between tumor stage, higher tumor grade, presence of vascular invasion, shorter overall survival, shorter disease-free survival and high expression of GPC3. The subgroup analyses based on sample size, cutoffs and follow-up period were also conducted to examine the association between GPC3 and OS and also to increase the homogeneity of study. Current study found a significant association between GPC3 expression and poor prognosis of HCC and specially related to the HCC invasion and progression. It was recommended to design more prospective studies based on the relationship between GPC3 and HCC to confirm our results.

Preparation of a monoclonal antibody against the carcinoembryonic antigen, glypican‑3

The carcinoembryonic antigen, glypican‑3 (GPC3), is a putative therapeutic target and diagnostic marker of hepatoma. In the present study, a monoclonal antibody (mAb) specifically against GPC3 was obtained via cloning the sequence of GPC3 via polymerase chain reaction and inserting it into a pET16b vector prior to transfection into Escherichia coli (E. coli) BL21. BALB/c mice were immunized with 20 µg purified antigen by intrasplenic embedding. Splenocytes and mouse myeloma cells SP2/0 were fused; then, the hybridoma cells were screened by an indirect ELISA. The properties of the mAb were examined by western blotting and immunofluorescence analysis against the purified protein. The results revealed that the prokaryotic expression vector of GPC3 had been successfully generated and GPC3 was stably expressed in E. coli BL21. A stable hybridoma cell line, 2F3, was generated in the present study, which produced mAbs against GPC3. The mAb 2F3 had a high antibody titer and the isotype was identified as IgG1/κ; 2F3 hybridomas had a median chromosome number of 98. Western blot and immunofluorescence analyses revealed that 2F3 specifically recognized recombinant and native GPC3. The 2F3 clone was proposed as a stable secretor of this mAb against GPC3. The results of present study indicated that the successful preparation of recombinant GPC3 protein and an anti‑human GPC3 mouse mAb may be provide a basis for developments in the diagnosis and treatment of liver cancer.

Both glypican-3/Wnt/β-catenin signaling pathway and autophagy contributed to the inhibitory effect of curcumin on hepatocellular carcinoma

AIM

The aim of this study is to investigate the role of glypican-3(GPC3)/wnt/β-catenin signaling pathway and autophagy in the regulation of hepatocellular carcinoma (HCC) growth mediated by curcumin.

METHODS

HepG2 cells were treated with various concentrations of curcumin and/or GPC3-targeting siRNA in the presence or absence of 3-MA. Cell proliferation and apoptosis were determined by MTT and TUNEL assay, respectively. Expression of GPC3, β-catenin, c-myc, LC3, and Beclin1 was determined by western blotting. In addition, curcumin was tested in tumor xenografts mice model, Caliper IVIS Lumina II was used to monitor the tumor growth, and GPC3/wnt/β-catenin signaling proteins were determined by western blotting.

RESULTS

Curcumin treatment led to proliferation inhibition and apoptosis induction in HepG2 cells in a concentration-dependent manner, and suppressed HCC tumor growth in vivo. Further analysis showed that curcumin treatment inactivated Wnt/β-catenin signaling and decreased GPC3 expression, silencing of GPC3 expression promoted the effects of curcumin on Wnt/β-catenin signaling. In addition, inhibiting autophagy by 3-MA relieved curcumin-dependent down-regulation of GPC3.

CONCLUSION

Curcumin suppressed HCC tumor growth through down-regulating GPC3/wnt/β-catenin signaling pathway, which was partially mediated by activation of autophagy.

Expression of hepatic Wnt5a and its clinicopathological features in patients with hepatocellular carcinoma

BACKGROUD

Wingless-type MMTV integration site family member 5a (Wnt5a) is involved in carcinogenesis. However, little data are available in Wnt5a signaling with hepatocellular carcinoma (HCC). In the present study, we investigated the expression of hepatic Wnt5a in HCC and the role of Wnt5a in HCC progression and outcome.

METHODS

Wnt5a expression and cellular distribution in HCCs and their matched paracancerous tissues from 87 patients were analyzed with tissue microarray and immunohistochemistry and compared with hepatic Wnt3a signaling. Wnt5a expression was categorized into low or high based on immunohistochemistry. Overall survival rate of HCC patients was estimated in correlation with the hepatic Wnt5a level using Kaplan-Meier method; the survival difference between patients with low and those with high Wnt5a was compared with log-rank test; and prognostic analysis was carried out with Cox regression.

RESULTS

Total incidence of Wnt5a expression in the HCC tissues was 70.1%, which was significantly lower (χ²= 13.585, P < 0.001) than that in their paracancerous tissues (88.5%). Significant difference of Wnt5a intensity was found between HCC and their paracancerous tissues (Z = 8.463, P < 0.001). Wnt5a intensity was inversely correlated with Wnt3a signaling (r = -0.402, P < 0.001) in HCC tissues. A decrease of Wnt5a expression in relation to the clinical staging from stage I to IV and low or no staining at advanced HCC were observed. Wnt5a level was related to periportal embolus (χ²= 11.069, P < 0.001), TNM staging (χ²= 8.852, P < 0.05), 5-year survival (χ²= 4.961, P < 0.05), and confirmed as an independent prognosis factor of HCC patients (hazard ratio: 1.957; 95% confidence interval: 1.109-3.456; P < 0.05).

CONCLUSIONS

The decrease of hepatic Wnt5a signaling is associated with HCC progression and poor prognosis.

Low expression of trafficking protein particle complex 4 predicts poor prognosis in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. Tumor recurrence and metastasis are major factors that contribute to the poor outcome of patients with HCC. However, it is difficult to predict the prognosis of hepatocellular carcinoma. Trafficking Protein Particle Complex 4 (Trappc4), is associated with tumorigenesis. The present study aimed to detect Trappc4 expression in HCC and its association with clinicopathological patient data. More importantly, this study reveals the relationship between Trappc4 and the prognosis of hepatocellular carcinoma. A total of 148 HCC tissues were assessed for expression of Trappc4 mRNA and protein with (reverse transcription polymerase chain reaction) RT-PCR (n=36), Western blotting (n=4) and immunohistochemistry (n=148), respectively. The data show that Trappc4 mRNA and protein are expressed at low levels in HCC tissues compared to adjacent tissues. Immunohistochemical analysis revealed that 148 cases of HCC showed different degrees of positive expression. Statistical analysis showed that expression of Trappc4 was associated with histological differentiation, TNM stage, and vascular invasion (P < 0.05), but did not correlate with the patient's age, gender, tumor size (P > 0.05). Most importantly, HCC patients with low expression of Trappc4 had shorter survival time compared to patients with high expression. Trappc4 might be involved in the pathogenesis of HCC and could be an important prognostic marker in HCC patients.

Autophagy suppresses proliferation of HepG2 cells via inhibiting glypican-3/wnt/β-catenin signaling

Introduction

Autophagy plays an important role in the growth and survival of hepatocellular carcinoma (HCC) cells through several target proteins or signaling pathways. Glypican-3 (GPC3) is a new reliable HCC marker, which is involved in tumor growth in HCC, primarily mediated by wnt/β-catenin signaling.

Objective

The present study aimed to identify the role of autophagy in the proliferation of HepG2 cells through GPC3/wnt/β-catenin signaling.

Results and discussion

Results demonstrated that induction of autophagy by nutrition starvation and rapamycin treatment led to the downregulation of GPC3 expression in HepG2 cells, accompanied by the decreased expression of wnt downstream target genes (β-catenin, c-myc and cyclin D1). On the other hand, inhibition of autophagy by 3-methyl adenine (3-MA) could rescue rapamycin-directed downregulation of GPC3 and wnt/β-catenin target genes and augment the proliferation of HepG2 cells. Furthermore, interference of GPC3 by siRNA suppressed wnt/β-catenin signaling and attenuated 3-MA stimulation of HepG2 cell proliferation. More interestingly, the mRNA of GPC3 remained unchanged when the protein levels of GPC3 were decreased by autophagy activation, suggesting that induction of autophagy may accelerate the degradation of GPC3.

Conclusion

These results suggest that autophagy suppresses proliferation of HepG2 cells partially by inhibition of GPC3/wnt/β-catenin signaling.

Proteoglycans remodeling in cancer: Underlying molecular mechanisms

Extracellular matrix is a highly dynamic macromolecular network. Proteoglycans are major components of extracellular matrix playing key roles in its structural organization and cell signaling contributing to the control of numerous normal and pathological processes. As multifunctional molecules, proteoglycans participate in various cell functions during morphogenesis, wound healing, inflammation and tumorigenesis. Their interactions with matrix effectors, cell surface receptors and enzymes enable them with unique properties. In malignancy, extensive remodeling of tumor stroma is associated with marked alterations in proteoglycans' expression and structural variability. Proteoglycans exert diverse functions in tumor stroma in a cell-specific and context-specific manner and they mainly contribute to the formation of a permissive provisional matrix for tumor growth affecting tissue organization, cell-cell and cell-matrix interactions and tumor cell signaling. Proteoglycans also modulate cancer cell phenotype and properties, the development of drug resistance and tumor stroma angiogenesis. This review summarizes the proteoglycans remodeling and their novel biological roles in malignancies with particular emphasis to the underlying molecular mechanisms.

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.

Novel specific markers for hepatocellular carcinoma: Perspective on clinical applications

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Despite continuous global efforts aimed at HCC eradication and improvements in various treatment techniques, the prognosis of HCC remains very poor. How to monitor malignant transformation of hepatocytes or diagnose HCC at early stage is still a medical challenge. A growing understanding of the multiple pathogenic factors including hepatitis B virus or hepatitis C virus infection, lipid accumulation, aflatoxin B1 intake and so on suggests that hepatocarcinogenesis is a multistep process. A large number of oncogenes or tumor suppressor genes have been identified. Early screening of HCC patients has been reported to confer a survival benefit. Although serum alpha-fetoprotein (AFP) and hepatoma-specific AFP have been used as conventional tumor markers, they often show false-positive results and lack sufficient sensitivity and specificity. In order to provide optimal treatment for each patient with HCC, more precise and effective biomarkers are urgently needed in all phases of management from early detection to staging, treatment monitoring, and prognosis evaluation. Recently, numerous studies have shown the clinical utility of novel blood-based biomarkers, such as circulating tumor cells, key signal molecules or specific proteins, long non-coding RNAs, and microRNAs. In this article, we will review some novel HCC-related biomarkers and discuss their future perspective on clinical applications.

Oncogenic secretory clusterin in hepatocellular carcinoma: Expression at early staging and emerging molecular target

Secretory clusterin (sCLU) is associated with hepatocellular carcinoma (HCC) progression by contributing to angiogenesis, chemoresistance, cell survival, and metastasis. However, the sCLU expression at early stage of HCC progression remains to be clarified. In this study, the alteration of sCLU oncogenicity was firstly evaluated in HCC- and their para-cancerous- tissues. The incidence of sCLU expression in HCC was significantly higher than that in their non-tumorous tissues at message RNA (mRNA) or protein level, gradually increasing with tumor-node-metastasis (TNM) staging. Abnormal sCLU expression was associated with the poor differentiation, TNM stage, and considered as an independent prognostic factor for HCC patients. Furthermore, silencing sCLU gene transcription inhibited the colony formation and proliferation of HCC cells, with decreasing phosphorylation level of AKT and GSK-3β in HCCLM3 cells in vitro and significantly suppressed the HCC xenograft growth in vivo, suggesting that sCLU with oncogenicity should be not only an early indicator but also novel potential molecular-targeted therapy for HCC.

Advances in the study of oncofetal antigen glypican-3 expression in HBV-related hepatocellular carcinoma

Early specific diagnosis and effective treatment of hepatocellular carcinoma (HCC) are crucial. Expression of membrane-associated heparan sulfate proteoglycan glypican-3 (GPC-3) was recently found to increase as part of the malignant transformation of hepatocytes, and this increase is especially marked in patients with hepatitis B virus (HBV) infection, periportal cancerous embolus, or extra-hepatic metastasis. According to data from basic and clinical studies, the oncofetal antigen GPC-3 is a highly specific diagnostic biomarker of HCC and an indicator of its prognosis, and GPC-3 is also a promising target molecule for HCC gene therapy since it may play a crucial role in cell proliferation, metastasis, and invasion and it may mediate oncogenesis and oncogenic signaling pathways. This review summarizes recent advances in the use of oncofetal antigen GPC-3 to diagnose HBV-related HCC, estimate its prognosis, and its targeted therapy.