Molecular biology of gliomas.

Gliomas are the most common primary neoplasm of the brain. Unfortunately, they are often refractory to treatment and portend a poor prognosis. However, recent discoveries have shed light on the molecular events driving glioma growth, including abnormalities of three major molecular pathways: extracellular growth factors and their receptors (eg, EGF/EGFR and PDGF/PDGFR), signal transduction cascades (eg, RAS and AKT), and cell proliferation controls (eg, INK4A-ARF). Each of these abnormalities is described in detail. Efforts to inhibit abnormally activated pathways are underway through multi-institutional clinical trials.