Hull’s Magic Box: Keeping Brain Tumour Biopsies “Alive” in the Lab Brings Research Opportunities for New Therapies and Earlier Diagnosis of Brain Tumour

Abstract AIMS Assess/evaluate apoptosis in GBM samples maintained on a microfluidics system in response to GSK3368715 and other PRMT inhibitors, currently in clinical trials, with the ultimate goal of synergising with personalised patient care and precision medicine. Investigate the effect of treating GBM biopsies on-chip with PRMT inhibitors at the molecular level, including RNA and protein modifications. METHOD GBM biopsies are received from Hull Royal Infirmary and maintained on-chip for 8-days. They are perfused with media, at a rate of 3 μl/min, mimicking the in vivo environment and allowing real-time analysis of tumour behaviour. PRMT inhibitors, such as GSK3368715, are added to the media, in conjunction with TMZ, to determine their efficacy ex vivo using a range of techniques, such as: immunohistochemistry, cell viability assays, protein analysis and RNA-sequencing. RESULTS We show that PRMT inhibition increases apoptosis five-fold above the control, untreated GBM-on-chip samples. This is compounded by cell viability assays, which have indicated that cell viability in these post-chip tissues is reduced by 30% upon treatment with 1μM GSK3368715. Additionally, western blot analysis has indicated that PRMT inhibition with GSK3368715 appears to switch the methylation status of fused-in-sarcoma (FUS) protein in GBM biopsies. CONCLUSION These results indicate that PRMT inhibition may not only be a viable target for GBM therapy, but could also highlight a mechanism for re-sensitising MGMT-negative GBM to TMZ. This data produces an exciting argument for further research into the use of this novel inhibitor for improving prognosis for patients diagnosed with this devastating disease.