Secreted reporter proteins, a valuable complementary tool for non-invasive preclinical monitoring of brain tumour growth

Malignant glioma and glioblastoma multiforme (GBM) are the most common and aggressive primary brain cancers with a very low dismal mean survival after initial diagnosis (1), emphasizing the need for novel treatment options. Several novel therapeutics have been identified for the treatment of malignant brain tumours, but despite strong preclinical data, very few successes have been achieved in clinical trials (2). The dichotomy between potential successful preclinical therapeutic agents and the ineffectiveness of the drug in patients underscores the need for better predictive preclinical models. The ideal model is a highly reproducible tumour model that mimics the key histopathological, genetic and imaging characteristics encountered in human GBMs. The most relevant models are isogenic orthotopic models, in which the complex micro-environmental interaction between glioma cells, the central nervous system and the immune system are present during tumour growth and treatment (3).