Identifying Molecular Subtypes of GBM

The article, "Integrated Genomic Analysis Identifies Clinically Relevant Subtypes of Glioblastoma Characterized by Abnormalities in PDGFRA, IDH1, EGFR, and NF1," was published yesterday in the journal Cancer Cell and it will revolutionize the way we diagnose and treat GBM. Using state of the art molecular and genetic research techniques, the investigators confirmed what we have believed clinically for some time: GBM is not one disease. Even though GBMs look the same under the microscope, there are significant differences in tumor behavior and response to treatment amongst people diagnosed with "GBM." 


The data was obtained through The Cancer Genome Atlas (TCGA). TCGA was developed in order to understand the molecular and genetic events that lead to cancer formation so that rational and novel therapies could be created. GBM was one of the first four cancers to be included in the TCGA project.


The article described four new subtypes of GBM as well as their molecular and genetic characteristics:

• Classical: amplification of EGFR gene, deletion of CDKN2A gene (codes for p16INK4A and p14ARF), lack of p53 mutation
• Mesenchymal:  deletion of NF1 gene and high expression of tumor necrosis factor family of genes
• Proneural:  high levels of PDGFRA expression, mutations in IDH1 and p53 genes
• Neural:  expression of neuron markers

The hope is that this information will lead to new treatments that target an individual tumor's particular set of genetic and molecular abnormalities, and new biomarkers that might lead to diagnostic tests.

The UMBTC is working with Moffitt Cancer Center in Tampa to study the molecular and genetic profile of brain tumor tissue.  Call is at 906-225-7739 to learn more about this program and ways you might be able to participate.