Overexpression of GPC3 inhibits hepatocellular carcinoma cell proliferation and invasion through induction of apoptosis

Recovery of synaptic loss and depressive-like behavior induced by GATA1 through blocking of the neuroinflammatory response

GATA1, a member of the GATA transcription factor family, is a critical factor in hematopoietic system development. In a previous study, we demonstrated the increased expression of GATA1 in the dorsolateral prefrontal cortex (dlPFC) of patients suffering from depression and described its role as a transcriptional repressor of synapse-related genes. In this study, we investigated how GATA1 globally altered gene expression using multi-omics approaches. Through the combined analyses of ChIPseq, mRNAseq, and small RNAseq, we profiled genes that are potentially affected by GATA1 in cultured cortical neurons, and Gene Ontology (GO) analysis revealed that GATA1 might be associated with immune-related functions. We hypothesized that GATA1 induces immune activation, which has detrimental effects including synapse loss and depressive-like behavior. To test this hypothesis, we first performed a microglial morphometric analysis of a brain having overexpression of GATA1 because microglia are the resident immune cells of the central nervous system. Fractal analysis showed that the ramification and process length of microglia decreased in brains having GATA1 overexpression compared to the control, suggesting that GATA1 overexpression increases the activation of microglia. Through flow cytometry and immunohistochemical analysis, we found that activated microglia showed pro-inflammatory phenotypes characterized by the expression of CD86 and CD68. Finally, we demonstrated that the effects of GATA1 overexpression including synapse loss and depressive-like behavior could be blocked by inhibiting microglial activation using minocycline. These results will elucidate the regulatory mechanisms of GATA1 that affect pathophysiological conditions such as depression and provide a potential target for the treatment of depression.

Hereditary Conditions Associated with Elevated Cancer Risk in Childhood

Received January, 31, 2023 Revised March, 16, 2023 Accepted March, 18, 2023 Widespread use of the next-generation sequencing (NGS) technologies revealed that a significant percentage of tumors in children develop as a part of monogenic hereditary diseases. Predisposition to the development of pediatric neoplasms is characteristic of a wide range of conditions including hereditary tumor syndromes, primary immunodeficiencies, RASopathies, and phakomatoses. The mechanisms of tumor molecular pathogenesis are diverse and include disturbances in signaling cascades, defects in DNA repair, chromatin remodeling, and microRNA processing. Timely diagnosis of tumor-associated syndromes is important for the proper choice of cancer treatment, genetic counseling of families, and development of the surveillance programs. The review describes the spectrum of neoplasms characteristic of the most common syndromes and molecular pathogenesis of these diseases.

Inhibition of Glypican-3 Cleavage Results in Reduced Cell Proliferation in a Liver Cancer Cell Line

INTRODUCTION

Glypican-3 (GPC3) is a surface-bound proteoglycan overexpressed in pediatric liver cancer and utilized clinically as an immunohistochemical tumor marker. Furin is a proprotein convertase that is ubiquitously expressed and shown to modify GPC3 post-translationally. In experimental models of epithelial-based cancers, furin inhibition decreased tumor cell migration and proliferation representing a potential therapeutic target.

METHODS

Using a synthetic furin inhibitor, we evaluated proliferation, migration, protein, and RNA expression in two liver cancer cell lines, HepG2 (GPC3-positive) and SKHep1 cells (GPC3-negative). Total furin protein and GPC3 protein expression were assessed to evaluate functional levels of furin.

RESULTS

There was a reduction in HepG2 proliferation with addition of furin inhibitor at the 48-h timepoint, however there was an increase in HepG2 migration.

CONCLUSIONS

GPC3 cleavage in hepatoblastoma (HB) has a role in cell proliferation with therapeutic potential, however furin inhibition is not an appropriate target for GPC3-expressing HB due to increased migration which may enhance metastatic potential.

Identification of HLA-A2 restricted epitopes of glypican-3 and induction of CTL responses in HLA-A2 transgenic mice

Hepatocellular carcinoma (HCC) is a malignant tumor with high mortality, but lacks effective treatments. Carcinoembryonic antigen glypican-3 (GPC3) is a tumor-associated antigen overexpressed in HCC but rarely expressed in healthy individuals and thus is one of the most promising therapeutic targets. T cell epitope-based vaccines may bring light to HCC patients, especially to the patients at a late stage. However, few epitopes from GPC3 were identified to date, which limited the application of GPC3-derived epitopes in immunotherapy and T cell function detection. In this study, a total of 25 HLA-A0201 restricted GPC3 epitopes were in silico predicted and selected as candidate epitopes. Then, HLA-A0201⁺/GPC3⁺ HCC patients' PBMCs were collected and co-stimulated with the candidate epitope peptides in ex vivo IFN-γ Elispot assay, by which five epitopes were identified as real-world epitopes. Their capacity to elicit specific CD8⁺ T cells activation and proliferation was further confirmed by in vitro co-cultures of patients' PBMCs with peptide, in vitro co-cultures of healthy donors' PBLs with DCs and peptide, T2 cell binding assay as well as HLA-A2 molecule stability assay. Moreover, the in vivo immunogenicity of the five validated epitopes was confirmed by peptides cocktail/poly(I:C) vaccination in HLA-A0201/DR1 transgenic mice. Robust epitope-specific CD8⁺ T cell responses and cytotoxicity targeting HepG2 cells were observed as detected by IFN-γ Elispot, intracellular IFN-γ staining and cytolysis assay. This study provided novel GPC3 CTL epitopes for the development of T cell epitope vaccines and evaluation of GPC3 specific T cell responses.

Current status and future directions of hepatocellular carcinoma-targeted nanoparticles and nanomedicine

INTRODUCTION

Hepatocellular carcinoma (HCC) is a major health problem worldwide. Conventional therapies covering either chemotherapy or combination therapy still have sub-optimal responses with significant adverse effects and toxicity. Moreover, tumor cells usually acquire resistance quickly for traditional approaches, limiting their use in HCC. Interest in nanomedicine due to minimal systemic toxicity and a high degree of target-specific drug-delivery have pulled the attention of health scientists in this area of therapeutics.

AREA COVERED

The review covers the incidence and epidemiology of HCC, proposed molecular drug targets, mechanistic approach and emergence of nanomedicines including nanoparticles, lipidic nanoparticles, vesicular-based nanocarrier, virus-like particles with momentous therapeutic aspects including biocompatibility, and toxicity of nanocarriers along with conclusions and future perspective, with an efficient approach to safely cross physiological barriers to reach the target site for treating liver cancer.

EXPERT OPINION

Remarkable outcomes have recently been observed for the therapeutic efficacy of nanocarriers with respect to a specific drug target against the treatment of HCC by existing under trial drugs.

Effects of the organochlorine p,p'-DDT on MCF-7 cells: Investigating metabolic and immune modulatory transcriptomic changes

The organochlorine pesticide dichloro-diphenyl-trichloroethane (DDT) is persistent in the environment and leads to adverse human health effects. High levels in breast milk pose a threat to both breast tissue and nursing infants. The objectives of this study were to investigate DDT-induced transcriptomic alterations in enzymes and transporters involved in xenobiotic metabolism, immune responses, oxidative stress markers, and cell growth in a human breast cancer cell line. MCF-7 cells were exposed to both environmentally-relevant and previously-tested concentrations of p,p'-DDT in a short-term experiment. Significant up-regulation of metabolizing enzymes and transporters (ACHE, GSTO1, NQO1 and ABCC2) and oxidative stress markers (CXCL8, HMOX-1, NFE2L2 and TNF) was clearly observed. Conversely, UGT1A6, AHR and cell growth genes (FGF2 and VEGFA) were severely down-regulated. Identification of these genes helps to identify mechanisms of p,p'-DDT action within cells and may be considered as useful biomarkers for exposure to DDT contamination.

Elevated GPC3 level promotes cell proliferation in liver cancer

The aim of the present study was to investigate the biological role of glypican 3 (GPC3), and to identify its mechanism and clinical significance in the carcinogenesis of liver cancer. A total of 114 patients with liver cancer were involved. Their clinical data, hematoxylin and eosin-stained and Antigen Ki-67 protein (Ki-67) and GPC3 immunohistochemically-stained liver cancer tissue sections were analyzed to evaluate the correlation between the liver cancer proliferation, differentiation and GPC3 expression. Fluorescence microscopy, western blotting, MTT and reverse transcription quantitative polymerase chain reaction (RT-qPCR) assays were performed in HepG2 and HLE cell lines to investigate the potential mechanisms of action. Among the 114 patients with liver cancer enrolled in the present study, 12 exhibited well-differentiated liver cancer, of which 6 (50%) were positive for GPC3. A total of 30 cases exhibited poorly differentiated liver cancer; 26 (87%) of these expressed GPC3 and 11 cases (37%) demonstrated strong positive expression levels. The other 72 liver cancer cases were moderately differentiated; 75% (54/72) of these expressed GPC3 and 12.5% (9/72) exhibited strong positive expression levels. There was a significant association between the levels of GPC3 expression and liver cancer differentiation (χ²=16.306, P=0.008). Ki-67 staining as the criteria of the liver cancer cell proliferation index also indicated a cross correlation between liver cancer proliferation and GPC3 levels. Among the 39 liver cancer samples with a cell proliferation index <5%, only 2.6% (1/39) exhibited strong positive GPC3 staining, but of the 16 cases with a high cell proliferation index >50%, 6 exhibited strong GPC3 staining (37.5%). The difference of cell proliferation indexes between cancer cells were well, moderate and poorly differentiated, and was markedly significant (χ²=26.334, P=0.002), and suggested that liver cancer cell proliferation was positively correlated with GPC3 expression (r=0.316, P=0.001). Consistently, in vitro analysis indicated that GPC3 promoted HepG2 and HLE cell growth, which was more apparent in HepG2 cells. The RT-qPCR results indicated that GPC3 promoted proliferation through the Hedgehog (Hh) pathway in HepG2 cells, but not in HLE cells. In the present study, it was demonstrated that patients with liver cancer with higher GPC3 levels exhibited poorer differentiation and higher proliferation levels. In vitro GPC3 may promote liver cancer cell lines proliferation through the Hh pathway.

Prognostic significance of glypican-3 expression in hepatocellular carcinoma: A meta-analysis

BACKGROUND

In recent years, an increasing number of studies has been published analyzing the possible prognostic utility of glypican-3 (GPC3) in hepatocellular carcinoma (HCC), but the results are still controversial. The aim of this meta-analysis was to evaluate possible association between GPC3 expression and patients' survival.

METHODS

Relevant publications which assessed GPC3 expression with survival outcome in HCC patients were searched from Pubmed, Embase, Web of Science, and the Cochrane library. Survival outcome (odds ratios or hazard ratios) was synthesized with a fixed or random effects meta-analysis. Publication bias and sensitivity analyses were also conducted. Statistical analysis was performed by STATA 12.0 and Review Manager software 5.3.

RESULTS

Fifteen studies including 2336 HCC cases were analyzed systematically in our meta-analysis. The main results showed that GPC3 high expression was significantly associated with later tumor stage, higher tumor grade, presence of vascular invasion, shortened overall survival, and disease-free survival. Subgroup analyses for GPC3 on HCC overall survival according to the studies categorized by sample size, follow-up period, and cut-offs were also conducted.

CONCLUSION

Our findings suggested that GPC3 may play a role in cancer invasion and progression and may be related to poor prognosis of HCC. Further mechanical research or multicenter cohort studies are needed to confirm these findings.

The significance of glypican-3 expression profiling in the tumor cellular origin theoretical system for hepatocellular carcinoma progression

BACKGROUND AND AIM

Glypican-3 (GPC3) expression is correlated with poor prognosis and progression in hepatocellular carcinoma (HCC). HCC progression can be associated with the differentiation status of tumor cell before malignant transformation. Our aim was to investigate the dynamic expression of GPC3 during tumor cells differentiation and to explore the role and theoretical significance of GPC3 in malignant essence of HCC.

METHODS

The expressions of tissue GPC3 and alpha fetoprotein (AFP) were detected by immunohistochemical staining. The tumor size, lymph node involvement, and metastasis were determined by pathological and imaging studies. HepG2 cells were induced to differentiate by all-trans retinoic acid (ATRA). Differentiation was evaluated by cytokeratin 19, gamma glutamyl transferase, and AFP through reverse transcription-polymerase chain reaction and real-time polymerase chain reaction. GPC3 staining was analyzed through flow cytometry.

RESULTS

Based on the immunohistochemical staining, the enrolled 316 cases were divided into two subtypes, namely, GPC3+ HCC and GPC3- HCC. Significant differences in morphology, histology variations, AFP expression, TNM staging, and overall survival curves were observed between two subtypes. During HCC differentiation induced by ATRA, the mean value of GPC3 expression treated with ATRA was much lower than the ones in placebo. There were significant differences between GPC3+ HCC and GPC3- HCC for cumulative intrahepatic and extrahepatic recurrence in early stage HCC (P = 0.009, P = 0.010).

CONCLUSIONS

Glypican-3 is correlated with the clinical malignant behavior of HCC. Moreover, GPC3 phenotype changes from positive to negative during tumor cells differentiation. Meanwhile, GPC3 plays a significant role in tumor cellular origin theoretical system, which can better reflect the malignant essence of tumors.

Can glypican-3 be a disease-specific biomarker?

Background

Glypican-3 (GPC3) is a cell surface-bound proteoglycan which has been identified as a potential biomarker candidate in hepatocellular carcinoma, lung carcinoma, severe pneumonia, and acute respiratory distress syndrome (ARDS). The aim of our review is to evaluate whether GPC3 has utility as a disease-specific biomarker, to discuss the potential involvement of GPC3 in cell biology, and to consider the changes of GPC3 gene and protein expression and regulation in hepatocellular carcinoma, lung cancer, severe pneumonia, and ARDS.

Results

Immunohistochemical studies have suggested that over-expression of GPC3 is associated with a poorer prognosis for hepatocellular carcinoma patients. Expression of GPC3 leads to an increased apoptosis response in human lung carcinoma tumor cells, and is considered to be a candidate lung tumor suppressor gene. Increased serum levels of GPC3 have been demonstrated in ARDS patients with severe pneumonia.

Conclusions

Glypican-3 could be considered as a clinically useful biomarker in hepatocellular carcinoma, lung carcinoma, and ARDS, but further research is needed to confirm and expand on these findings.

Recent advances in hepatocellular carcinoma therapy

Hepatocellular carcinoma (HCC), also called malignant hepatoma, is one of the deadliest cancers due to its complexities, reoccurrence after surgical resection, metastasis and heterogeneity. Incidence and mortality of HCC are increasing in Western countries and are expected to rise as a consequence of the obesity epidemic. Multiple factors trigger the initiation and progression of HCC including chronic alcohol consumption, viral hepatitis B and C infection, metabolic disorders and age. Although Sorafenib is the only FDA approved drug for the treatment of HCC, numerous treatment modalities such as transcatheter arterial chemoembolization/transarterial chemoembolization (TACE), radiotherapy, locoregional therapy and chemotherapy have been tested in the clinics. Polymeric nanoparticles, liposomes, and micelles carrying small molecules, proteins, peptides and nucleic acids have attracted great attention for the treatment of various cancers including HCC. Herein, we discuss the pathogenesis of HCC in relation to its various recent treatment methodologies using nanodelivery of monoclonal antibodies (mAbs), small molecules, miRNAs and peptides. Synopsis of recent clinical trials of mAbs and peptide drugs has been presented with a broad overview of the pathogenesis of the disease and treatment efficacy.

Microarray-based identification of genes associated with cancer progression and prognosis in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths. The average survival and 5-year survival rates of HCC patients still remains poor. Thus, there is an urgent need to better understand the mechanisms of cancer progression in HCC and to identify useful biomarkers to predict prognosis.

METHODS

Public data portals including Oncomine, The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) profiles were used to retrieve the HCC-related microarrays and to identify potential genes contributed to cancer progression. Bioinformatics analyses including pathway enrichment, protein/gene interaction and text mining were used to explain the potential roles of the identified genes in HCC. Quantitative real-time polymerase chain reaction analysis and Western blotting were used to measure the expression of the targets. The data were analysed by SPSS 20.0 software.

RESULTS

We identified 80 genes that were significantly dysregulated in HCC according to four independent microarrays covering 386 cases of HCC and 327 normal liver tissues. Twenty genes were consistently and stably dysregulated in the four microarrays by at least 2-fold and detection of gene expression by RT-qPCR and western blotting showed consistent expression profiles in 11 HCC tissues compared with corresponding paracancerous tissues. Eleven of these 20 genes were associated with disease-free survival (DFS) or overall survival (OS) in a cohort of 157 HCC patients, and eight genes were associated with tumour pathologic PT, tumour stage or vital status. Potential roles of those 20 genes in regulation of HCC progression were predicted, primarily in association with metastasis. INTS8 was specifically correlated with most clinical characteristics including DFS, OS, stage, metastasis, invasiveness, diagnosis, and age.

CONCLUSION

The significantly dysregulated genes identified in this study were associated with cancer progression and prognosis in HCC, and might be potential therapeutic targets for HCC treatment or potential biomarkers for diagnosis and prognosis.

Effect of co-transfection of miR-520c-3p and miR-132 on proliferation and apoptosis of hepatocellular carcinoma Huh7

OBJECTIVE

To investigate the effects of co-transfection of miR-520c-3p and miR-132 on proliferation and apoptosis of hepatocellular carcinoma Huh7.

METHODS

Hepatocellular carcinoma Huh7 was cultured in vitro and lipidosome was used to transfect miR-520c-3p and miR-132, respectively or together. The effects of transfection of miR-520c-3p and miR-132 on proliferation and apoptosis of Huh7 were detected by CCK8 and Annexin V staining and flow cytometry, and the expression level of the targeted gene of over-expressed miR-520c-3p and miR-132 was determined by Western blot and realtime PCR.

RESULTS

Compared with the control group, the proliferation ability of Huh7 of the single transfected and co-transfected miR-520c-3p and miR-132 decreased significantly, and the apoptosis ratio increased distinctly (P < 0.05). Besides, the effect of the co-transfection group was better than that of the single transfection group. The protein levels of GPC3 (Glypican-3) and YAP (Yes-associated protein), the target genes transfected only by miR-520c-3p and miR-132, respectively, reduced obviously (P < 0.05), which was similar with the co-infected cells, but cells transfected by miR-132 only showed a decrease of YAP.

CONCLUSIONS

The co-transfection of miR-520c-3p and miR-132 can target-regulate the expression of GPC3 and YAP, enhance the exhibition effect on proliferation of hepatocellular carcinoma Huh7 and induce cell apoptosis synergistically.

Prediction and preliminary screening of HLA-A*0201-restricted epitope peptides of human GPC3

In response to the limited therapeutic option for hepatocellular carcinoma (HCC), immunotherapy as a promising approach points out a new direction to the cure of tumours through specific recognition and elimination of tumour cells by the immunity-enhanced autologous immunocytes of patients. Few effective tumour antigens, however, are alternative in addition to alpha fetoprotein or tumour cell lysates. Recent studies have demonstrated that glypican-3 (GPC3) is not only a promising diagnostic marker, but also ideal therapeutic target to HCC. In this study, potential HLA-A*0201 GPC3 peptides were screened with three epitope prediction software, the binding affinity of 13 predicted epitopes with high scores was determined by T2 cells binding assay and four optimal epitopes were identified. This is the first study in which the optimal HLA-A*0201 GPC3 epitopes were screened from a large number of candidates predicted by three software. The optimized HLA-A*0201 GPC3 peptides will provide new epitope candidates for HCC immunotherapy.

Roles of Combined Glypican-3 and Glutamine Synthetase in Differential Diagnosis of Hepatocellular Lesions

BACKGROUND

Hepatocellular carcinoma (HCC) is the fifth most prevalent cancer and thirdly leading cause of cancer-related death worldwide. The estimated risk of hepatocellular carcinoma is 15 to 20 times as high among persons infected with HCV as it is among those who are not infected, with most of the excess risk limited to those with advanced hepatic fibrosis or cirrhosis. Glypican3 (GPC3) plays a key role in relation to signaling with growth factors, regulating the proliferative activity of cancer cells. Glutamine synthetase (GS) catalyzes the synthesis of glutamine from glutamate and ammonia in the mammalian liver. GS was suggested as a specific marker for tracing cell lineage relationships during hepatocarcinogenesis. In normal liver, GS expression is seen in pericentral hepatocytes, but not by midzonal or periportal hepatocytes. In HCC, strong and diffuse GS expression in seen in tumor cells.

RESULTS

Glypican3 immunopositvity was highly specific and sensitive indicator for hepatocellular carcinoma as well as glutamine synthetase which was found to be a sensitive and specific indicator for development of hepatocellular carcinoma when compared to cirrhosis, liver cell dyspalsia and metastatic carcinomas. Statistical analysis revealed a significant association between GPC3 and GS with tumor size (P=0.003, p=0.006, respectively). Diffuse staining significantly associated with large tumor size while, focal and mixed staining was detected more with small tumor size. Studying the relation with tumor grade also revealed significant association between diffuse GPC3 and GS staining with high tumor grade. Diffuse staining was detected in 91.7% and 100% respectively of poorly differentiated specimens and only in 33.3% and 22.2% of well differentiated specimens.

CONCLUSIONS

While using GPC3 and GS to screen for premalignant hepatic lesions remains controversial, our data suggest that GPC3 and GS may be a reliable diagnostic immunomarkers to distinguish HCC from benign hepatocellular lesions. However, negative immunostaining should not exclude the diagnosis of HCC.

Clinical correlation of calpain-1 and glypican-3 expression with gallbladder carcinoma

Gallbladder carcinoma (GBC) possesses a poor prognosis, which is primarily attributed to the lack of early and timely surgical intervention. Calpain-1 and glypican-3 have been implicated in the progression of various types of cancer. The present study aimed to detect the expression of calpain-1 and glypican-3 in GBC, and analyzed whether the expression levels of these proteins correlated with any clinicopathological variables. A total of 100 patients with GBC and 30 patients with cholecystitis who accepted surgical treatment were enrolled in the present study. Pathological and clinical data were obtained from all patients. The expression of calpain-1 and glypican-3 was detected in paraffin-embedded tissues by immunohistochemistry. Calpain-1 expression was manually assessed with an immunohistochemical H-score with a slight modification. Glypican-3 expression was assessed as negative and positive. The correlations between protein expression and clinicopathological characteristics, and the associations between the proteins were analyzed. All patients exhibited positive expression of calpain-1. Notably, the high expression rate of calpain-1 was significantly increased in patients with GBC, compared with patients with cholecystitis (32.0 vs. 6.7%; χ²=7.668; P=0.006), suggesting that calpain-1 expression may be associated with progression from cholecystitis to GBC. In addition, the positive rate of glypican-3 expression was 53.0% in patients with GBC and 63.3% in patients with cholecystitis, with no significant difference (χ²=0.997; P=0.318). Furthermore, the expression of calpain-1 and glypican-3 had no significant correlation with gender, age, degree of tumor differentiation and tumor-node-metastasis classification in patients with GBC. Notably, the expression of calpain-1 and glypican-3 displayed a significant positive correlation in patients with GBC (r=0.517; P<0.01), but a significantly negative correlation (r=-0.856; P<0.01) in patients with cholecystitis. In conclusion, calpain-1 expression may be associated with progression from cholecystitis to GBC. Combined detection of calpain-1 and glypican-3 may be beneficial for prognosis assessment of GBC.

Lentivirus vectors construction of SiRNA targeting interference GPC3 gene and its biological effects on liver cancer cell lines Huh-7

OBJECTIVES

To build GPC3 gene short hairpin interference RNA (shRNA) slow virus vector, observe expression of Huh-7 GPC3 gene in human liver cell line proliferation apoptosis and the effect of GPC3 gene influencing on liver cancer cell growth, and provide theoretical basis for gene therapy of liver cancer.

METHODS

Hepatocellular carcinoma cell line Huh-7 was transfected by a RNA interference technique. GPC3 gene expression in a variety of liver cancer cell lines was detected by fluorescence quantitative PCR. Targeted GPC3 gene sequences of small interfering RNA (siRNA) PGC-shRNA-GPC3 were restructured. Stable expression cell lines of siRNA were screened and established with the help of liposomes (lipofectamine(TM2000)) as carrier transfection of human liver cell lines. In order to validate siRNA interference efficiency, GPC3 siRNA mRNA expression was detected after transfection by using RT-PCR and Western blot. The absorbance value of the cells of blank group, untransfection group and transfection group, the cell cycle and cell apoptosis were calculated, and effects of GPC3 gene on Huh-7 cell proliferation and apoptosis were observed.

RESULTS

In the liver cancer cell lines Huh-7, GPC3 gene showed high expression. PGC-shRNA-GPC3 recombinant plasmid was constructed successfully via sequencing validation. Stable recombinant plasmid transfected into liver cancer cell lines Huh-7 can obviously inhibit GPC3 mRNA expression level.

CONCLUSIONS

The targeted GPC3 siRNA can effectively inhibit the expression of GPC3.

Downregulation of glypican-3 expression increases migration, invasion, and tumorigenicity of human ovarian cancer cells

Glypican-3 (GPC3) is a membrane of heparan sulfate proteoglycan family involved in cell proliferation, adhesion, migration, invasion, and differentiation during the development of the majority of mesodermal tissues and organs. GPC3 is explored as a potential biomarker for hepatocellular carcinoma screening. However, as a tumor-associated antigen, its role in ovarian cancer remains elusive. In this report, the expression levels of GPC3 in the various ovarian cancer cells were determined with quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and GPC3 expression in ovarian cancer UCI 101 and A2780 cells was knocked down by siRNA transfection, and the effects of GPC3 knockdown on in vitro cell proliferation, migration, and invasion were respectively analyzed by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay and Transwell migration assay. Additionally, the effect of GPC3 knockdown on in vivo tumorigenesis were investigated in athymic nude mice. The results indicated that GPC3 knockdown significantly promoted cell proliferation and increased cell migration and invasion by upregulation of matrix metalloproteinase (MMP)-2 and MMP-9 expression and downregulation of tissue inhibitor of metalloproteinase-1 expression. Additionally, GPC3 knockdown also increased in vivo tumorigenicity of UCI 101 and A2780 cells and final tumor weights and volumes after subcutaneous cell injection in the nude mice. The results of immunohistochemical staining and Western blotting both demonstrated a lower expression of GPC3 antigen in the tumors of GPC3 knockdown groups than that of negative control groups. Moreover, transforming growth factor-β2 protein expression in the tumors of GPC3 knockdown groups was significantly increased, which at least contributed to tumor growth in the nude mice. Taken together, these findings suggest that GPC3 knockdown promotes the progression of human ovarian cancer cells by increasing their migration, invasion, and tumorigenicity, and suggest that GPC3 is a potential therapeutic target for ovarian cancer patients.

Oncofetal glypican-3: Specific diagnosis and targeted-therapy for primary liver cancer

The development and progression of primary hepatocellular cancer (PHC) are a multi- factorial, multi-step, and multi-center complex process. Its early diagnosis and effective treatments are of the most importance. Glypican-3 (GPC-3) plays a crucial role in PHC progression. Increased GPC-3 expression has been found during hepatocyte malignant transformation. GPC-3 levels in PHC patients are related to HBV infection, TNM stage, periportal cancerous embolus, and extra-hepatic metastasis. Circulating GPC-3 or GPC-3 mRNA with AFP enhances the positive rate up to 94.3% for PHC diagnosis. Down-regulating GPC-3 by specific siRNA could alter liver cancer cell biological behaviors such as migration, metastasis, and invasion; and inhibit nude mouse xenograft growth with decreased β-catenin, p-GSK3β, and cyclin D1 expression, suggesting that oncofetal GPC-3 is not only a specific diagnostic biomarker for PHC, but also a promising target for PHC therapy.

Glypican-3 promotes epithelial-mesenchymal transition of hepatocellular carcinoma cells through ERK signaling pathway

Glypican-3 (GPC3), a membrane-associated heparan sulfate proteoglycan, is frequently upregulated in hepatocellular carcinoma (HCC). However, how GPC3 contributes to the progress of HCC is largely unclear. The present study investigated the association between GPC3 expression and HCC clinicopathological characteristics, and particularly focused on the role and underlying mechanisms of GPC3 in HCC epithelial-mesenchymal transition (EMT). Remarkably elevated expression of GPC3 was demonstrated in HCC tumor tissues compared with paired non-tumor tissues in 45 patients with HCC by quantitative real-time PCR, immunohistochemistry, and western blotting, respectively. Furthermore, the tissue expression of GPC3 was increased during HCC progression from Barcelona Clinic Liver Cancer stage A or B to stage C. The enhanced levels of GPC3 in HCC tumor tissues were tightly correlated to the expression of the EMT-associated proteins and tumor vascular invasion. Patients with GPC3-high expression in tumor tissues displayed significantly shorter survival time than those with GPC3-low expression (P=0.001). Consistent with the findings in patients, HepG2 cells, which expressed high levels of GPC3, showed stronger capacity of migration and significant EMT-like changes when compared to those HCC cells with low levels of GPC3, e.g., Hep3B and Huh7 in scratch, Transwell assays and western blotting. Furthermore, administration with exogenous GPC3 in HCC cells activated extracellular signal-regulated kinase (ERK) and significantly enhanced cell migration and invasion. The behavior was significantly inhibited by the ERK inhibitor PD98059. Together, our studies show that GPC3 contributes to HCC progression and metastasis through impacting EMT of cancer cells, and the effects of GPC3 are associated with ERK activation.