Related Experiment Video
Updated: Apr 19, 2026
Three-Dimensional 3D Tumor Spheroid Invasion Assay
Published on: May 1, 2015
α integrin targeting for radiosensitization of three-dimensionally grown human head and neck squamous cell carcinoma
Anne Steglich1, Anne Vehlow1, Iris Eke1
1OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany; Department of Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany.
Abstract:
Integrin cell adhesion molecules play a crucial role in tumor cell resistance to radio- and chemotherapy and are therefore considered attractive targets for cancer therapy. Here, we assessed the role of β1 integrin-interacting α integrin subunits in more physiological three-dimensional extracellular matrix grown head and neck squamous cell carcinoma (HNSCC) cell cultures for evaluating cytotoxic and radiosensitizing potential. α2, α3, α5 and α6 integrins, which are overexpressed in HNSCC according to Oncomine database analysis, were coprecipitated with β1 integrin. More potently than α2, α5 or α6 integrin inhibition, siRNA-based α3 integrin targeting resulted in reduced clonogenic cell survival, induced apoptosis and enhanced radiosensitivity. These events were associated with diminished phosphorylation of Akt, Cortactin and Paxillin. Cell line-dependently, simultaneous α3 and β1 integrin inhibition led to higher cytotoxicity and radiosensitization than α3 integrin blocking alone. Stable overexpression of wild-type and constitutively active forms of the integrin signaling mediator focal adhesion kinase (FAK) revealed FAK as a key determinant of α3 integrin depletion-mediated radiosensitization. Our findings show that α3 integrin is essentially involved in HNSCC cell radioresistance and critical for a modified cellular radiosensitivity along with β1 integrins.
Insights
Targeting alpha3 (α3) integrin in head and neck squamous cell carcinoma (HNSCC) reduces tumor cell survival and enhances radiosensitivity. Combined inhibition of alpha3 and beta1 (β1) integrins further increases these effects, offering potential cancer therapy strategies.
Area of Science:
- Integrin biology
- Cancer cell biology
- Radiobiology
Background:
- Integrins are crucial for tumor cell resistance to cancer therapies.
- Head and neck squamous cell carcinoma (HNSCC) exhibits integrin overexpression.
- Targeting integrins offers a promising strategy for cancer treatment.
Purpose of the Study:
- To investigate the role of β1 integrin-interacting α integrins in HNSCC radioresistance.
- To evaluate the cytotoxic and radiosensitizing potential of targeting specific α integrins.
- To explore the involvement of focal adhesion kinase (FAK) in α3 integrin-mediated radiosensitization.
Main Methods:
- Utilized 3D extracellular matrix grown HNSCC cell cultures.
- Analyzed α and β1 integrin interactions via coprecipitation.
- Employed siRNA to target α3 integrin and assessed its effects on cell survival, apoptosis, and radiosensitivity.
- Investigated signaling pathways including Akt, Cortactin, and Paxillin phosphorylation.
- Overexpressed focal adhesion kinase (FAK) to determine its role in radiosensitization.
Main Results:
- α2, α3, α5, and α6 integrins were found to coprecipitate with β1 integrin in HNSCC.
- siRNA-mediated α3 integrin inhibition significantly reduced clonogenic survival, induced apoptosis, and enhanced radiosensitivity.
- α3 integrin targeting diminished phosphorylation of Akt, Cortactin, and Paxillin.
- Combined α3 and β1 integrin inhibition showed greater cytotoxicity and radiosensitization than α3 inhibition alone.
- FAK was identified as a key mediator of α3 integrin depletion-induced radiosensitization.
Conclusions:
- α3 integrin plays a critical role in HNSCC radioresistance.
- Targeting α3 integrin, particularly in combination with β1 integrins, can modify cellular radiosensitivity and enhance treatment efficacy.
- FAK is essential for the radiosensitizing effects of α3 integrin targeting in HNSCC.
More Related Videos
06:11Therapy Testing in a Spheroid-based 3D Cell Culture Model for Head and Neck Squamous Cell Carcinoma
Published on: April 20, 2018
07:29Intramucosal Inoculation of Squamous Cell Carcinoma Cells in Mice for Tumor Immune Profiling and Treatment Response Assessment
Published on: April 22, 2019