The rationale of targeting neutrophils with dapsone during glioblastoma treatment.

Data from past research is presented showing that neutrophils are active participants in new vessel formation in normal physiology, in proliferating human endometrium, in non-cancer pathologies as in the pannus of rheumatoid arthritis, and in various cancers, among them glioblastoma. These data show that interleukin-8 (IL-8) is a major chemokine attracting neutrophil infiltrates in these states. Since the old anti-Hansen's disease drug dapsone inhibits neutrophil migration along an IL-8 gradient towards increasing concentrations, and is used therapeutically for this attribute to good effect in dermatitis herpetiformis, bullous pemphigoid and rheumatoid arthritis, we suggest dapsone may deprive glioblastoma of neutrophil-mediated growth promoting effects. We review past research showing that vascular endothelial growth factor, VEGF, is carried predominantly intracellularly within neutrophils--only 2% of circulating VEGF is found free in serum. Based on the available evidence summarized by the authors, dapsone has a strong theoretical potential to become a useful anti-VEGF, anti-angiogenic agent in glioblastoma treatment.