Glioblastoma is an extremely aggressive brain tumour with limited treatment options.
Recent progress in using immunotherapy-based treatment options in other tumour types has spurred interest in developing approaches that might be effective in this devastating malignancy.
Myeloid-derived innate immune cells, such as macrophages, microglia, and myeloid-derived suppressor cells, are known to be present within glioblastomas.
Previous work suggested that the tumour microenvironment triggers microglia and macrophages to polarise to a cell state that dampens immune responses to tumours; however, there has been only a limited assessment of the immune cell populations in patient tumours.
In this month's issue of JCI Insight, Amy Heimberger and colleagues at the University of Texas MD Anderson Cancer Center provide a comprehensive analysis of myeloid lineage immune cells in the circulation and in tumours of glioblastoma patients.
Their extensive survey relied on immune phenotyping, whole genome microarray analysis, and microRNA expression profiling to characterise myeloid cells in surgical samples from 43 patients.
Their results surprisingly indicated that glioblastoma-associated myeloid cells were most similar to non-polarised cells.
Importantly, these findings suggest that strategies to stimulate myeloid cells to assume an anti-tumour identity may be possible and merit future exploration.
(29 Mar 2017)