Upregulation of ecto-5′-nucleotidase in human neuroblastoma SH-SY5Y cells on differentiation by retinoic acid or phorbolester

Abstract

Ecto-5′-nucleotidase has been suggested to play an important role in neural development and differentiation in situ and in vitro. In order to investigate whether neural differentiation is associated with an upregulation of ecto-5′-nucleotidase, we used all trans-retinoic acid or phorbol-12-myristate-13-acetate to induce a neural phenotype in the human neuroblastoma cell line SH-SY5Y. Both agents initiated a reduction in proliferation and an increase in polarity of SH-SY5Y cells as well as a time dependent increase in ecto-5′-nucleotidase activity. Non-specific ecto-phosphatase activity remained unaltered. Northern hybridization experiments suggest that the increase in ecto-5′-nucleotidase activity is due to increased enzyme synthesis rather than due to enzyme activation. The upregulation of ecto-5′-nucleotidase in differentiating neuroblastoma cells would be consisted with a functional role of ecto-5′-nucleotidase in neural development.