alpha 6 beta 4 and alpha 6 beta 1 Integrins in astrocytomas and other CNS tumors

Laminin may alter the biological behavior of gliomas. Therefore, we investigated the expression of two laminin receptors, alpha 6 beta 1 and alpha 6 beta 4 integrins in normal brain, astrogliotic brain, and astrocytomas as compared to other central nervous system (CNS) tumors. In most CNS tumors, the expression of these integrins was unchanged in neoplastic as compared to normal counterpart cells. In contrast, increased numbers of reactive and neoplastic astrocytes expressed beta 4 integrin as compared to normal astrocytes, whereas alpha 6 and beta 1 integrin expression did not change. Conversely, lower numbers of astrocytoma blood vessels expressed beta 4, whereas all blood vessels in normal brain expressed beta 4. These data suggest that the profile of laminin receptors changes in neoplastic astrocytes and in astrocytoma blood vessels; this change may play an important role in astrocytoma pathogenesis.