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Functional proteomic screen identifies a modulating role for CD44 in death receptor-mediated apoptosis
Robert S Hauptschein1, Kevin E Sloan, Claudia Torella
1Department of Physiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA.
Cancer Research
|March 9, 2005
Summary
Researchers identified CD44 as a key regulator of apoptosis, a process cancer cells evade. Targeting CD44 using fluorophore-assisted light inactivation (FALI) offers a novel therapeutic strategy to overcome cancer
Area of Science:
- Molecular Biology
- Cancer Research
- Immunology
Background:
- Apoptotic evasion is a critical hallmark of cancer, contributing to resistance against chemotherapy.
- Identifying proteins that control apoptosis is essential for developing new cancer therapies.
- Fas ligand-mediated apoptosis is a key pathway that cancer cells often subvert.
Purpose of the Study:
- To develop and utilize a high-throughput screening method to identify proteins modulating Fas ligand-mediated apoptosis.
- To discover novel therapeutic targets for overcoming apoptosis resistance in cancer.
Main Methods:
- Development of a high-throughput screen using fluorophore-assisted light inactivation (HTS-FALIpop) coupled with a caspase activity assay.
- Screening of 96 single-chain variable fragment antibodies (scFvs) targeting surface proteins on HT-1080 fibrosarcoma cells.
- Validation of identified targets using specific monoclonal antibodies and FALI.
Main Results:
- HTS-FALIpop successfully identified proteins that modulate Fas ligand-mediated apoptosis.
- CD44 was identified as a novel regulator of Fas-mediated apoptosis.
- Targeting CD44 with FALI demonstrated antiapoptotic effects in multiple cancer cell lines and protected against other death receptor ligands.
Conclusions:
- CD44 plays a crucial role in regulating Fas receptor-mediated apoptosis at the cell surface.
- CD44-targeted FALI represents a novel mechanism for apoptosis modulation with potential therapeutic applications.
- This approach offers a promising strategy to overcome apoptosis resistance in various cancer types.
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