Involvement of apolipoprotein E in glioblastoma: immunohistochemistry and clinical outcome.

We hypothesised that apolipoprotein E (apoE) influences brain tumours by delivery of lipids to tumour cells and by analogy with other brain insults. APOE gene analysis was performed for 126 glioblastomas, the commonest primary brain tumour. Neither APOE epsilon2 nor epsilon4 alleles were significantly associated with differences in post-operative survival. However, there was apoE immunoreactivity of tumour cells, macrophages in areas of necrosis and astrocytes nearby. The immunohistochemistry findings support the hypothesis that apoE is involved in the delivery of lipids to tumour cells and in the recycling of lipids by macrophages in necrotic areas, raising the possibility that apoE-mediated lipid transport may represent a new therapeutic target in brain tumours.