GROWTH-FACTOR RECEPTORS AND MEDULLOBLASTOMA

Growth factors and their receptors play important roles in the regulat ion of cell division, development and differentiation. Neurotrophins a re growth factors which have not been shown, until recently, to be ass ociated with human neoplasia. Medulloblastoma is a central nervous sys tem tumor which is thought to arise from the external granule cell lay er of the cerebellum. Platelet Derived Growth Factor (PDGF) or Epiderm al Growth Factor (EGF) and/or their receptors have not been found to h ave a significant role in the development of this tumor. Neurotrophins , however, which regulate cerebellar development in a time-dependent m anner, appear to be important in medulloblastoma and the presence of h igh levels of TrkC expression, a neurotrophin receptor? is associated with a better outcome. The potential role of these growth factors and their receptors in manipulating the behavior of this tumor is discusse d.