Utilisation of semiconductor sequencing for the detection of predictive biomarkers in glioblastoma

Glioblastoma is the most aggressive form of brain cancer, with debilitating symptoms including seizures, memory loss, difficulties in language processing, muscle weakness and visual changes. The standard treatment for glioblastoma involves a combination of surgery, radiation and chemotherapy but have limited impact on survival with the five year survival rate being around 7%.

The exponential increase in modern anti-cancer agents called targeted therapies and immunotherapies are directed at the genetic DNA mutations that underlie the development and progression of cancer. Targeted agents therefore offer the great advantage that they directly attack the cancer cells but leave normal cell relatively undisturbed. Targeted agents therefore show increased specificity and reduced toxicity when compared with conventional chemotherapy.

One of the hurdles to the implementation of targeted therapies into routine clinical practice has been lack of comprehensive genetic screening for these therapy linked DNA mutations at diagnosis. The processing of the tissue biopsies using formaldehyde and wax embedding for diagnosis results in fragmentation of the DNA which makes analysis for mutations a challenge.

In our recent study we show that semiconductor sequencing can be used to robustly screen the fragmented DNA and RNA from routine glioblastoma biopsy/resection samples. This enables comprehensive DNA profiling to be undertaken as part of the routine diagnostic workflow allowing linkage of detected mutations to a broad range of potential targeted therapies and immunotherapies that can be considered should standard treatment protocols fail to control the disease.