pRb2/p130 gene overexpression induces astrocyte differentiation.

There are many data on the activity of the RB gene in neural differentiation and apoptosis, but the role of pRb2/p130 in neuronal and glial maturation has been far less investigated. To elucidate the role of pRb2/p130 in astrocyte development we overexpressed this protein in astrocytoma and normal astrocyte cultures by adenoviral-mediated gene transfer. In astrocytoma cells, p130/RB2 overexpression resulted in a significant reduction of cell growth and in an increased G(0)/G(1) cell population. We did not observe any induction of programmed cell death as determined by TUNEL reaction. Interestingly, pRb2/p130 overexpression induced astrocyte differentiation. Astrocyte cell cycle arrest and differentiation seemed to proceed through a way distinct from the p53 pathway.