ABSTRACT
Our knowledge about etiology and pathogenesis of primary brain tumors in humans and animals has been greatly enhanced during the past two decades. Oncogenic viruses and chemical carcinogens have been used successfully in experimental models and have revealed important new information. Advancements in molecular biology have expanded our understanding of neurocarcinogenic processes on a mo lecular level. It has become possible to define the interactions of chemical carcino gens with DNA molecules and assess their consequences. Methods are now avail able to explore the roles of oncogenes, growth factors, and supressor genes in the neurooncogenic process.
