The cellular and molecular biology of medulloblastoma.

Medulloblastomas are prototypical of primitive neuroectodermal tumors which are some of the most frequent malignant brain tumors of childhood. The cell biology of medulloblastomas is still poorly understood, but recent studies of the expression of trophic factors and their receptors in medulloblastomas and the development of animal models of primitive neuroectodermal tumors may provide clues as to the induction or progression of these tumors. For example, they could clarify mechanisms that regulate cell death, proliferation and differentiation in these tumors.