GPC3 Antibody, Biotin conjugated
Description
Definition and Mechanism
The GPC3 antibody binds specifically to the glypican-3 protein, a GPI-anchored proteoglycan involved in Wnt signaling and tumor growth. Biotin conjugation enables detection via streptavidin-based assays (e.g., ELISA, immunohistochemistry) . The antibody’s specificity is critical, as GPC3 is minimally expressed in normal tissues but highly expressed in 70% of HCC cases, making it a tumor marker .
Applications
Research and Diagnostics
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Immunohistochemistry (IHC): Used to identify GPC3 in HCC tissues, distinguishing malignant cells from normal liver tissue. For example, the GPC3/8148R clone (Bio-Techne) is optimized for paraffin-embedded sections .
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Flow Cytometry: Detects GPC3 on cancer cells for phenotyping or sorting. The GPC3/1534R clone (Bio-Techne) is CyTOF-ready and suitable for multi-parameter analysis .
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ELISA: Quantifies soluble GPC3 in patient sera, aiding in biomarker validation .
b. Therapeutic Development
GPC3 antibodies are being explored for targeted therapies. For instance, HN3, a conformation-specific antibody, inhibited HCC cell proliferation by blocking Yes-associated protein (YAP) signaling and showed efficacy in xenograft models (Kd = 0.6 nM) .
Research Findings
Clinical Relevance
GPC3-targeted therapies are advancing in clinical trials. For example, GC33, a humanized anti-GPC3 antibody, showed limited monotherapy efficacy in phase II trials, highlighting the need for combination strategies (e.g., bispecific antibodies or immune checkpoint inhibitors) . Emerging data suggest that biotin-conjugated antibodies could facilitate real-time monitoring of GPC3 expression in patients undergoing treatment.
Product Specs
Constituents: 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
- The areas under the receiver operating curve (AUROC) value, sensitivity, and specificity of glypican 3 (GPC3) for hepatoblastoma (HB) pretreatment group versus all controls were all significantly lower than those of alpha-fetoprotein (AFP). PMID: 28378832
- GPC3 operates through a complex molecular signaling network. From the balance of these interactions, the inhibition of breast metastatic spread induced by GPC3 emerges. PMID: 30267212
- Its surface is modified with anti-GPC3 antibody. PMID: 29916268
- Data suggests that transcriptionally targeted delivery of transgene in HCC cells can be achieved using the GPC3 promoter, and this targeting strategy produces limited toxicity to normal liver cells PMID: 29563582
- High GPC3 expression is associated with Hepatocellular Carcinoma. PMID: 28429175
- Study demonstrated that GPC3 expression is inversely associated with glucose metabolism, suggesting that GPC3 may play a role in regulating glucose metabolism in hepatocellular carcinoma. PMID: 29398870
- The intravenous injection of SF-PL/siGPC3 into nude mice bearing subcutaneous human HepG2 xenografts effectively inhibited tumor growth and also increased the survival rates of animals. These results revealed the great potential of the PEI-modified liposomal nanomedicine carrying SF and siGPC3 to improve Hepatocellular carcinoma treatment. PMID: 29106433
- Invasive hepatocellular carcinoma (HCC) samples and HCC cell lines with high metastatic potential exhibited higher MXR7 expression. Overexpression of MXR7 promoted epithelial-mesenchymal transition (EMT) progress, and MXR7 depletion repressed the EMT phenotype. Human MXR7 protein is a mediator of EMT and metastasis in HCC. PMID: 28812296
- Overexpression of GPC3 was significantly associated with poor prognosis in patients with hepatocellular carcinoma. PMID: 29901640
- These data show that glycanation and convertase maturation are not required for soluble mutant GPC3 to inhibit hepatocellular carcinoma cell proliferation. PMID: 29345911
- Data indicate that several microRNAs target the oncogenic functions of glypican-3 (GPC3). PMID: 28476031
- Presence distinguishes aggressive from non-aggressive odontogenic tumors. PMID: 27647326
- GPC3 as a potential metastasis suppressor gene and suggest its value as a prognostic marker in gastric cancer. PMID: 27259271
- In this study, we systematically evaluated a series of CAR constructs targeting glypican-3 (GPC3), which is selectively expressed on several solid tumors. We compared GPC3-specific CARs that encoded CD3zeta (Gz) alone or with costimulatory domains derived from CD28 (G28z), 4-1BB (GBBz), or CD28 and 4-1BB (G28BBz). PMID: 27530312
- Data indicate that glypican-3 (GPC3) is an important regulator of epithelial-mesenchymal transition (EMT) in breast cancer, and a potential target for procedures against breast cancer metastasis. PMID: 27507057
- Glypican-3 overexpression in Wilms tumor correlates with poor overall survival. PMID: 28432433
- Glypican-3 has a role in HBV-related hepatocellular carcinoma. PMID: 27286460
- MOSPD1 is a possible candidate gene for DORV, probably in combination with GPC3. Further studies of the combined functions of MOSPD1 and GPC3 are needed, and identification of additional patients with MOSPD1 and GPC3 duplication should be pursued. PMID: 28636109
- Glypican-3 is correlated with the clinical malignant behavior of hepatocellular carcinoma and its phenotype changes from positive to negative during tumor cells differentiation. PMID: 28087980
- The diagnostic sensitivity for hepatocellular carcinoma increased to 72.8% (206 of the 283) when glypican 3 was combined with alpha-fetoprotein. PMID: 26370140
- The lncRNA glypican 3 antisense transcript 1 (GPC3-AS1) has been reported to be a potential biomarker for hepatocellular carcinoma (HCC) screening. We observed a significant upregulation of GPC3-AS1 in HCC. Increased expression of GPC3-AS1 was associated with alpha-fetoprotein, tumor size, microvascular invasion, encapsulation, Barcelona Clinic Liver Cancer stage, and worse prognosis of HCC patients. PMID: 27573079
- Study provides the first evidence that GPC3 can modulate the PCSK9 extracellular activity as a competitive binding partner to the LDLR in HepG2 cells. PMID: 27758865
- By subsequent Sanger sequencing of genomic DNA, we could map the chromosomal break points to define a deletion size of 43,617 bp including exons 5 and 6 of the GPC3 gene. PMID: 28371070
- 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 hepatocellular carcinoma (HCC) immunotherapy. PMID: 27102087
- GPC3 and KRT19 overexpression are associated with carcinogenesis, progression, and poor prognosis in patients with PDAC and a valuable biomarker for diagnosis of PDAC. PMID: 27689616
- The clinical implication of GPC3 detection and targeting in the management of patients with hepatocellular carcinoma. Review. PMID: 26755876
- Glypican 3 expression showed a significant difference between endometrioid endometrial carcinoma and serous endometrial carcinoma, and it was significantly correlated with tumor grade, stage, and myometrial invasion. PMID: 26722522
- Data show that notum and glypican-1 and glypican-3 gene expression during colorectal cancer (CRC) development and present evidence to suggest them as potential new biomarkers of CRC pathogenesis. PMID: 26517809
- GPC3 expression was measured in hepatocellular carcinoma at different stages and correlated with prognosis. CK19+/GPC3+ HCC has the highest risk of intrahepatic metastasis, microvascular invasion, regional lymph node involvement, and distant metastasis. PMID: 26977595
- Review: Glypican-3 is a highly specific biomarker for the diagnosis of hepatocellular carcinoma and a promising therapeutic target. PMID: 26256079
- In South Korean hepatocellular carcinoma patients, GPC3 expression was more frequent in hepatocellular carcinoma with aggressive features, but it was not an independent prognostic biomarker. PMID: 26764243
- In this meta-analysis, GPC3 was found to be acceptable as a serum marker for the diagnosis of hepatocellular carcinoma. PMID: 26502856
- GPC3 may be a candidate marker for detecting lung squamous cell carcinoma. PMID: 26345955
- Study suggests that GPC3 is involved in HCC cell migration and motility through HS chain-mediated cooperation with the HGF/Met pathway, showing how HS targeting has potential therapeutic implications for liver cancer. PMID: 26332121
- Potential role of GPC3 in urothelial carcinogenesis warrants further investigation, especially the potential use of Glypican-3 for therapeutic and diagnostic purposes. PMID: 25896897
- Downregulation of glypican-3 expression increases migration, invasion, and tumorigenicity of ovarian cancer. PMID: 25967456
- GPC3 expression is an independent prognostic factor for postoperative hepatocellular carcinoma. PMID: 25432695
- Identify a GPC3-specific T-cell receptor. Expression of this receptor by T cells allows them to recognize and kill GPC3-positive hepatoma cells. PMID: 26052074
- High expression of glypican-3 is associated with hepatoblastoma. PMID: 25735325
- GPC3 and E-cadherin expressions are not independent prognostic factors in CRC. PMID: 25619476
- In HCC patients, sGPC3N levels were significantly increased (mean/median, 405.16/236.19 pg mL(-1) ) compared to healthy controls (p < 0.0001), and 60% of HCC cases (69/115) showed sGPC3N levels that were higher than the upper normal limit. PMID: 25784484
- GPC3 contributes to hepatocellular carcinoma progression and metastasis through impacting epithelial-mesenchymal transition of cancer cells, and the effects of GPC3 are associated with ERK activation. PMID: 25572615
- Most cases of hepatoblastoma and yolk sac tumor, and some cases of other tumors were found to express GPC3. On the other hand, GPC3 was physiologically expressed during the fetal and neoinfantile period under 1 year of age. PMID: 25344940
- OPN, SPINK1, GPC3, and KNPA2 were significantly over-expressed in HCC tissues. These genes may be useful in developing future biomarkers and therapeutic strategies for HCC. PMID: 25862856
- Data indicate that zinc-fingers and homeoboxes 2 (ZHX2) suppresses glypican 3 (GPC3) transcription by binding with its core promoter. PMID: 25195714
- Propose that the structural changes generated by the lack of cleavage determine a change in the sulfation of the HS chains and that these hypersulfated chains mediate the interaction of the mutant GPC3 with Ptc. PMID: 25653284
- GPC3 is associated with the HCC cell biological behavior. PMID: 25270552
- Data indicate that the triple stain of reticulin, glypican-3, and glutamine synthetae is useful in the differentiation of hepatocellular carcinoma, hepatic adenoma, and focal nodular hyperplasia. PMID: 25822763
- Data shows that GPC3 gene expression is downregulated in primary clear cell renal cell carcinoma; its overexpression arrest cells in G1 phase suggesting its role as tumor suppressor in clear cell renal cell carcinoma. PMID: 25168166
- This study demonstrated that highly expression of GPC3 could enrich hepatocellular carcinoma -related genes' mRNA expression and positive associate with dysplasia in cirrhotic livers. PMID: 25542894
Q&A
How do I validate the specificity of biotin-conjugated GPC3 antibodies in hepatocellular carcinoma (HCC) models?
Validation requires a multi-step approach:
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Positive/Negative Cell Line Controls: Use GPC3-expressing cell lines (e.g., HepG2, G1) and non-expressing lines (e.g., A431, SK-Hep1) for flow cytometry or immunofluorescence .
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Competitive Blocking: Pre-incubate the antibody with recombinant GPC3 protein (25–559 aa, HEK293-expressed) to confirm signal reduction .
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Western Blot Correlation: Compare antibody reactivity with commercial clones (e.g., 1G12) on HCC lysates to verify band consistency at ~63 kDa .
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Epitope Mapping: Perform ELISAs with N-terminal (25–358 aa) and C-terminal (359–550 aa) GPC3 fragments to confirm conformational binding requirements .
What experimental factors influence biotin-antibody performance in immunohistochemistry (IHC)?
Critical variables include:
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Antigen Retrieval: Use pH 9.0 Tris-EDTA buffer for formalin-fixed paraffin-embedded (FFPE) tissues to expose GPC3’s core protein .
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Endogenous Biotin Blocking: Apply avidin/biotin blocking kits to minimize background in liver tissues .
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Titration Range: Optimize antibody concentrations between 1–5 µg/mL for FFPE sections, as GPC3 expression varies by HCC subtype .
How do I select appropriate biotin conjugates for low-abundance GPC3 detection?
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High-Sensitivity Assays: Use streptavidin-HRP with chemiluminescent substrates for Western blots .
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Multiplex Imaging: Pair biotin-antibodies with fluorophore-streptavidin conjugates (e.g., Cy5) for co-detection of GPC3 with PD-L1 or CD34 .
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Avoid Blue Fluorophores: CF®405M/Cy2 conjugates exhibit higher background in hepatic tissues due to autofluorescence .
How do I resolve contradictory GPC3 expression data between IHC and serum ELISA in HCC studies?
Discrepancies often arise from:
Methodological Solutions:
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Use RNAscope® to correlate protein localization with GPC3 mRNA .
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Validate serum ELISA with mass spectrometry to confirm isoform specificity .
What strategies improve GPC3-targeted antibody-drug conjugate (ADC) efficacy in in vivo models?
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Affinity Optimization: Select clones with sub-nanomolar K<sub>D</sub> (e.g., HN3: 0.6 nM) for prolonged tumor retention .
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Linker Design: Use protease-cleavable linkers (e.g., Val-Cit) to ensure payload release in GPC3<sup>+</sup> lysosomes .
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Bystander Effect Mitigation: Employ non-membrane-permeable toxins (e.g., MMAE) to spare adjacent hepatocytes .
How does GPC3 glycosylation impact antibody binding in embryonic vs. neoplastic tissues?
GPC3 undergoes differential heparan sulfate (HS) modification:
| Tissue Type | HS Modification | Antibody Impact |
|---|---|---|
| Embryonic Liver | Full HS chains | Blocks access to core protein epitopes |
| Hepatoblastoma | Reduced HS | Enhances HN3/1G12 binding to cryptic epitopes |
Experimental Approach:
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Compare binding of HS-dependent (e.g., GC33) vs. HS-independent (e.g., HN3) clones via flow cytometry .
What controls are essential for GPC3 flow cytometry in mixed cell populations?
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Isotype Controls: Use biotin-conjugated rabbit IgG at matched concentrations .
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Competition Controls: Include 10-fold molar excess of recombinant GPC3 (25–559 aa) .
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Internal Reference: Spike GPC3<sup>−</sup> cells (e.g., A431) into samples to gate out non-specific binding .
How do I integrate GPC3 antibodies with single-cell RNA sequencing (scRNA-seq)?
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CITE-seq Workflow:
Why do some GPC3 antibodies fail to inhibit HCC proliferation despite high affinity?
Mechanistic factors include:
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Epitope Neutrality: Antibodies targeting C-terminal peptides (e.g., GC33) lack signaling inhibition vs. conformation-specific clones (e.g., HN3) .
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Downstream Pathway Redundancy: GPC3 knockdown may compensate via FGF2/β-catenin crosstalk .
Validation Experiment: -
Compare anti-proliferative effects of HN3 (cell-cycle arrest) vs. GC33 (ADCC-dependent) in in vitro clonogenic assays .
Can GPC3 biotin-antibodies enhance CRISPR-Cas9 delivery in HCC organoids?
Yes, via streptavidin-Cas9 conjugates:
