GPC3 is a heparan sulfate proteoglycan located on the cell membrane surface and serves as a liver cancer-specific associated antigen. This protein consists of a complex glycoconjugate formed by the covalent linkage of proteins, lipids, and sugars, anchored to the cell membrane via a glycosylphosphatidylinositol (GPI) moiety. The GPC3 gene is located on human chromosome Xq26, with a genomic structure spanning approximately 900 kb, featuring structural characteristics such as a central globular domain and glycosaminoglycan side chain attachment sites at the C-terminus. Its heparan sulfate groups interact with growth factors, their receptors, extracellular matrix proteins, and adhesion molecules, participating in the regulation of cell proliferation, differentiation, adhesion, and migration. GPC3 primarily functions through the Wnt signaling pathway, activating the canonical Wnt pathway via autocrine and paracrine mechanisms, leading to the overexpression of Wnt genes and promoting the growth of various tumor tissues. GPC3 is overexpressed in liver cancer tissues but absent or minimally expressed in normal liver tissues, making it an ideal target for liver cancer diagnosis and treatment. FITC-labeled GPC3 His-tagged protein can be used for quantitative detection of GPC3 protein expression levels and binding activity, providing a technical tool for liver cancer research.
Gene therapy mediated by GPC3 miRNA, shRNA, and siRNA has demonstrated significant efficacy in treating liver cancer. Knockout of the GPC3 gene in liver cancer cells alters the Wnt signaling pathway, elevating the expression levels of β-catenin and cyclin D1 in the cytoplasm, disrupting the Bax/Bcl-2/cytochrome c/caspase-3 pathway, inhibiting liver cancer cell proliferation, inducing apoptosis, and reversing tumor cell resistance to chemotherapy. Studies constructing GPC3-shRNA plasmids for transfection into HepG2 liver cancer cells showed transfection efficiencies exceeding 85%, with silencing efficiency at the mRNA level reaching 89.3% and significant suppression of GPC3 protein expression. Specific shRNA targeting GPC3 transcription inhibits liver cancer cell proliferation, migration, and invasion while inducing apoptosis. Co-culturing GPC3 gene-transfected dendritic cells with cytokine-induced killer cells elicits specific immune responses, markedly suppressing tumor growth. FITC-labeled GPC3 His-tagged protein can be used to assess changes in GPC3 protein expression post-gene transfection and validate gene silencing efficiency.
GPC3 peptide vaccines activate the patient's immune response to inhibit tumor growth, metastasis, and recurrence. Clinical studies on peptide vaccine therapy for advanced liver cancer indicate that GPC3 peptide vaccines exhibit excellent safety and tolerability, with a median survival time of 9.0 months. According to the Response Evaluation Criteria in Solid Tumors (RECIST), some patients achieved complete or partial remission. All treated patients developed GPC3-specific CTL responses, with higher CTL frequencies correlating with longer median survival times and overall survival. CTL frequency can serve as a predictive indicator for overall survival in liver cancer patients treated with GPC3 peptide vaccines. In vitro cell experiments revealed that cloned CTLs exhibit strong affinity for tumor cells expressing endogenous GPC3 and HLA-A*02:07 positivity, secreting IFNγ to exert cytotoxic effects. These studies provide preliminary evidence supporting the ability of subcutaneous GPC3 peptide vaccines to induce GPC3-specific CTLs for liver cancer treatment. FITC-labeled GPC3 His-tagged protein can be used to evaluate CTL recognition and binding to GPC3-positive tumor cells.
GPC3 antibodies represent a critical research direction in liver cancer immunotherapy, including GC33, HN3, YP7, and HS20. GC33 is a novel recombinant human monoclonal antibody targeting GPC3 with high affinity, exerting antitumor activity through antibody-dependent cell-mediated cytotoxicity (ADCC). Clinical studies suggest that liver cancer patients with high GPC3 expression may achieve better outcomes with GC33 antibody therapy, as the median time to tumor progression in the high-expression group was significantly longer than in the low-expression group. GC33 antibodies demonstrate excellent safety profiles with no severe adverse events reported. HN3 antibodies primarily recognize functional epitopes and inhibit the Wnt signaling pathway, directly suppressing liver cancer cell proliferation. HS20 antibodies target the heparan sulfate chains of GPC3, inhibiting Wnt3a/β-catenin activation and disrupting Wnt3a-GPC3 interactions. FITC-labeled GPC3 His-tagged protein can be used to assess the binding affinity of various GPC3 antibodies to antigens, providing quantitative data for antibody screening.
GPC3-targeted photoimmunotherapy is an effective method for treating liver cancer. Intravenous injection of IR700-YP7-labeled GPC3 antibodies combined with nanoparticle albumin-bound paclitaxel into liver cancer-bearing mice enables the GPC3 antibody to function as a tumor-targeting vector, guiding the labeled antibodies to deposit within the tumor. Subsequent infrared light irradiation induces tumor cell death and suppresses tumor growth. In liver cancer cells, miRNA-520c-3p expression is negatively correlated with GPC3 protein levels, with increased miRNA-520c-3p expression reducing GPC3 protein levels and inhibiting liver cancer cell proliferation and invasion. YAP protein is overexpressed in liver cancer and synergizes with GPC3 during liver cancer progression. Recombinant human YAP-1 effectively blocks GPC3-induced Huh7 cell proliferation and suppresses liver cancer development. GPC3 regulates hepatic stellate cells via the Hedgehog signaling pathway, inhibiting their capacity to promote liver cancer cell activity. FITC-labeled GPC3 His-tagged protein can be used to evaluate the impact of various therapeutic strategies on GPC3 expression and function.
Nanjing UA-BioTech Co., Ltd. (UA-Bio) has independently developed "FITC-Labeled GPC3 His Tag Protein, Human" (Product Code: UA011278), a high-performance fluorescent-labeled probe specifically designed for GPC3-targeted research and liver cancer diagnostic tool development. This protein is human-derived GPC3 with a His tag and FITC fluorescence labeling, capable of efficiently binding to anti-GPC3 antibodies or affinity ligands, providing a stable and reliable standardized tool for CAR-T cell therapy evaluation, antibody drug screening, and liver cancer biomarker research.
| Core Advantages | Detailed Parameters / Functional Description |
|---|---|
| High Purity and Intact Bioactivity | The product utilizes an internationally leading eukaryotic expression system and highly standardized purification processes, validated through multi-dimensional quality control to ensure >95% purity and correct native conformation (retaining intact glycosylation modifications). The FITC labeling process is optimized to maintain high labeling efficiency while preserving GPC3's high-affinity binding to antibodies, accurately simulating the antigenic properties of GPC3 on liver cancer cell surfaces.-- |
| High-Brightness FITC Labeling | Employing an optimized FITC labeling ratio, each GPC3 protein molecule is stably labeled with fluorescent dyes, emitting bright green fluorescence signals under 488 nm excitation, suitable for flow cytometry (FACS) and fluorescence microscopy, ensuring reliable evaluation and precise quantification of GPC3-targeted molecules.-- |
| Excellent Batch Consistency and Stability | Rigorous quality control is implemented throughout protein expression, labeling, and purification, combined with a comprehensive release testing system, ensuring consistent binding activity, uniform fluorescence intensity, and superior long-term stability for each batch. This provides a solid foundation for long-term, continuous GPC3-targeted research.-- |
| Ideal Tool for Multi-Scenario Applications | This protein excels in various applications, including CAR-T cell positivity rate detection by flow cytometry, anti-GPC3 antibody/antagonist screening, competitive binding assays, liver cancer biomarker analysis, and flow cytometry, making it widely applicable to GPC3-targeted CAR-T cell therapy development, liver cancer diagnostic research, and drug activity evaluation.-- |
| Complete Solutions and Professional Support | We provide thoroughly validated standard protocols, exemplary flow cytometry data, and detailed interpretation guides to help establish stable, reproducible GPC3-targeted molecule detection workflows. Nanjing UA-Bio's technical team offers comprehensive support for research design, experimental optimization, and data analysis.-- |
Nanjing UA-BioTech Co., Ltd. is dedicated to providing cutting-edge, high-quality core reagents and tools for immunology, cell therapy, and innovative drug development. For detailed technical parameters, validation data, or application inquiries regarding "FITC-Labeled GPC3 His Tag Protein, Human" (Product Code: UA011278), please feel free to contact us.
