Glioblastoma multiforme: the terminator.

Glioblastoma multiforme is the most aggressive of the gliomas, a collection of tumors arising from glia or their precursors within the central nervous system. Clinically, gliomas are divided into four grades; unfortunately, the most aggressive of these, grade 4 or glioblastoma multiforme (GBM), is also the most common in humans. Because most patients with GBMs die of their disease in less than a year and essentially none has long-term survival, these tumors have drawn significant attention; however, they have evaded increasingly cleaver and intricate attempts at therapy over the last half-century. The paper by Gromeier et al. (1) in this issue of PNAS is the newest chapter in this saga, describing a hybrid virus that infects and kills clonal human glioma cell lines, in culture and implanted in athymic mice, without affecting nonneoplastic cells within the brain. For those viewing this battle from a distance, the continued unsuccessful attempts at novel therapies for this disease may be difficult to understand. However, for those treating these patients, and certainly for the patients themselves, the importance and urgency of each attempt is clear.