In recent years, the tetraspanin KAI1 had been identified as a metastasis suppressor in many tumor entities. Hence, in many tumor types, including human ovarian cancer, decreased KAI1 expression levels have been detected correlating with tumor progression. Tetraspanins organize the cellular surface into large multimeric protein complexes, the so-called tetraspanin web, in which they interact e.g. with cell adhesion and signal transduction receptors of the integrin superfamily. In the present study, we showed that reintroduction of KAI1 in cultivated human ovarian cancer cells led to a significantly decreased integrin αvß3/vitronectin-dependent cell migration. This effect is possibly due to KAI1-provoked enhanced integrin αvß3-mediated cell adhesion to vitronectin to such an extent that cell mobility is largely impaired. An effect on cell spreading as a function of KAI1 expression could not be demonstrated.     «

In recent years, the tetraspanin KAI1 had been identified as a metastasis suppressor in many tumor entities. Hence, in many tumor types, including human ovarian cancer, decreased KAI1 expression levels have been detected correlating with tumor progression. Tetraspanins organize the cellular surface into large multimeric protein complexes, the so-called tetraspanin web, in which they interact e.g. with cell adhesion and signal transduction receptors of the integrin superfamily. In the present stu...     »