Prospective therapies for high-grade glial tumours: A literature review

Abstract

After three decades of intensive research, cytoreductive surgery remains the gold standard of treatment of malignant gliomas. Survivorship at both 1-year and 5-years has not drastically changed in the UK. Concomitant chemo- and radiotherapy has enhanced the efficiency of surgery, enabling more aggressive tumour resection whilst also preserving the surrounding healthy brain parenchyma. More accurate imaging techniques have also played a role in tumour identification, key to this has been pre- and intra-operative contrast enhancement and compounds that have a high affinity in binding to glioma cells. Intra-operative imaging has heralded the ability to give the operating surgeon continuous feedback to assess the completeness of resection. Research is shifting into investigating the complex cellular and molecular glial tumour-genesis, and has led to the development of efficacious chemotherapy agents and trial novel therapies. Oncolytic virotherapy has shown promise in clinical trials and gene therapy in-vitro studies. Surgery however remains the primary therapeutic option for the management of malignant gliomas removing the mass of proliferating malignant tumour cells and decompression of the space-occupying lesion.

Keywords: Chemotherapy; Glioma; Imaging; Neurosurgery; Radiotherapy.

Fig. 1

(i) Left, T1-weighted MRI of glioma-bearing rat brain after administration of gadolinium and CLIO-Cy5.5 administration. Right, T2-weighted MRI of the same rat brain after CLIO-Cy5.5 administration but before gadolinium administration. The images show good correlation in terms of tumour demarcation between the two contrast-agent modalities . 1 (ii) Magnification showing the tumour region in (i). (Image adapted).

Fig. 2

Schematic representations of Iron-oxide-CTX-nanoparticle inhibiting tumour cell invasion. (i) Surface chemistry of nanoprobe. (ii) Nanoprobe binding to lipid rafts of glioma cells containing MMP-2 and select ion channels .