HRH1 and glioblastoma: For the remaining 8 genes (HRH1, TYK2, RRM2, MAPK9, PDK3, XIAP, NR3C1, and NCOA1), an additional literature search in Pubmed and http://www.genecards.org/ was performed, which identified RRM2, MAPK9, and XIAP as members of biological pathways that play an important role in the development of GBM (Figure 1).