Background We investigated a novel therapeutic approach to glioblastoma (GBM) that targets cell-free chromatin particles (cfChPs) that are released from dying GBM cells and aggravate the oncogenic phenotype of living GBM cells. cfChPs can be deactivated by oxygen radicals (OR) generated upon oral administration of the nutraceuticals Resveratrol ® and Copper (Cu).

Methods Ten patients with glioblastoma awaiting surgery were administered 5.6 mg of Resveratrol ® and 560 ng of Copper (Cu) four times a day for an average of 11.6 ± 5.37 days. Another ten patients who did not receive R-Cu acted as controls. A tissue sample was taken at operation for analysis.

Results R-Cu treatment led to marked deactivation of cfChPs that were present in the tumour microenvironment, which was accompanied by a highly significant down-regulation in Ki-67, nine hallmarks of cancer, six immune check-points and three stem cell biomarkers as revealed by immuno-fluorescence analysis. Transcriptome sequencing detected marked upregulation of pro-apoptotic and down-regulation of anti-apoptotic genes. Also detected was down-regulation of PVRIG-2P, a homologue of immune checkpoint receptor PVRIG, which is a functional analogue of PD-L1.