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Published on: April 3, 2014
Heparan Sulfate Controls Nanoscale Assembly of GPC3-Wnt Receptor Complexes
Shaoli Lin1, David A Ball2, Mohamadreza Fazel2
1Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Biorxiv : the Preprint Server for Biology
|August 1, 2026
Summary
Heparan sulfate (HS) controls the nanoscale organization of Glypican-3 (GPC3) on cancer cells. This organization is crucial for Wnt3a/β-catenin signaling, impacting hepatocellular carcinoma progression.
Area of Science:
- Cell Biology
- Biophysics
- Cancer Research
Background:
- Glypican-3 (GPC3) is overexpressed in hepatocellular carcinoma, promoting tumor growth via Wnt3a/β-catenin signaling.
- The role of GPC3's nanoscale organization and dynamics at the cell surface in regulating this signaling pathway is not well understood.
Purpose of the Study:
- To investigate the spatial architecture and dynamics of GPC3 on hepatoma cells.
- To elucidate how heparan sulfate (HS) chains influence GPC3 organization and Wnt3a/β-catenin signaling.
Main Methods:
- Utilized nano-resolution MINFLUX imaging and single-molecule tracking.
- Performed functional assays and MINFLUX DNA-PAINT to analyze GPC3 behavior and Wnt3a interactions.
Main Results:
- GPC3 exists as single molecules and nanoscale clusters, exhibiting confined and free diffusion.
- HS chains form nanoscale corrals that restrict GPC3 movement; HS removal increases diffusion and disrupts confinement.
- Wnt3a stimulation promotes GPC3 assembly and enhances β-catenin signaling, a response diminished by HS loss.
- HS chains organize Wnt3a distribution, facilitating its binding to the Frizzled-1 receptor.
Conclusions:
- Heparan sulfate (HS) is critical for controlling the nanoscale organization and dynamics of Glypican-3 (GPC3).
- HS orchestrates GPC3 clustering and Wnt3a receptor engagement, thereby promoting efficient β-catenin signaling in hepatocellular carcinoma cells.
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