Glioma is a type of tumor that occurs in the brain and spinal cord. Gliomas begin in the supportive glial cells that surround nerve cells and help them function and there are three different types of glial cells which can produce tumors: astrocytes, oligodendrocytes and ependymal cells. Gliomas are classified according to the type of glial cell involved in the tumor, as well as the tumor's genetic features, which can help predict how the tumor will behave over time and the treatments most likely to work. As a group, gliomas are one of the most common types of brain tumors and comprise about 30 percent of all brain tumors and central nervous system tumors, but 80 percent of all malignant brain tumors. A glioma can affect your brain function and be life-threatening depending on its location and rate of growth. Gliomas do not usually metastasize by the bloodstream, but they can spread via the cerebrospinal fluid to the spinal cord.
Figure 1. The volcano plot shows the adjusted p-value compared to the difference in average protein expression (NPX) for all proteins in glioma compared to all other cancers. The lollipop plot shows the top 10 most important proteins resulting from the cancer prediction model with importance scores ranging between 0 to 100.
Pan-cancer protein panel
Only three proteins were selected to be included in the panel for identifcation of glioma (Table 1). The top protein GFAP is a brain specific filament, and serum GFAP is already considered as a diagnostic marker for glioblastoma multiforme (Jung CS et al. (2007)). The second protein, BCAN, is also known to be upregulated in glioma (Jaworski DM et al. (1996)), whereas the third protein, ADAMTS13, is more surprising since this blood hemostatis protein has been shown to be secreted primarily from liver cells, but recently was shown to also be expressed in astrocytes, microglial, neuroblastoma, and adult human brain endothelial cells (Lee M et al. (2013)).The three panel proteins predict patients with glioma with high specificity and sensitivity.