New approaches to molecular therapy of brain tumors.

Little progress has been made in the treatment outcome of patients with glioblastoma in the past 10 to 15 years, despite an aggressive multimodality regimen using surgery, radiation, and chemotherapy. New approaches, particularly molecular strategies, have become the clinicians' and scientists' hope for the future in brain-tumor therapy. Several molecular approaches have been shown to have in vitro and in vivo activities against brain tumor cells. These include the use of retroviral and adenoviral vectors, herpes simplex viruses, antisense vectors, and antisense oligonucleotides. Preclinical studies with the retroviral vector have already been extended to a clinical trial, clearly demonstrating the clinical potential of these molecular approaches.