Laminin Interactions with Head and Neck Cancer Cells under Low Fluid Shear Conditions Lead to Integrin Activation and Binding

Lymphatic metastasis of cancer cells involves movement from the primary tumor site to the lymph node, where the cells must be able to productively lodge and grow. Head and neck squamous cell carcinoma (HNSCC) cell lines cultured on placental laminin (laminin-511 is the major laminin), laminin-332 purified from human foreskin keratinocytes and human recombinant laminin-511, -211, -111, and -411. HNSCC cell lines bound to laminin-511 and -211 but also to -411 to a lower extent, under lymphodynamic low shear stress (0.07 dynes/cm2), consistent with lymph flow. Binding only occurred in the presence of shear stress and not in the absence of flow. The authors conclude that B1 integrins mediate tumor cell/lymph node interactions active under lymphodynamic flow. These interactions may drive growth and immunomodulation in this niche.