PTEN and glioblastoma: Immunohistochemistry staining showed glioblastoma multiforme (GBM) with E3 ubiquitin-protein ligase MIB (MIB)-1 (Ki-67) proliferation index of 23 to 25%, trioctyl phosphine oxide (TOPO) (++), and phosphatase and tensin homolog deleted on chromosome ten (PTEN) (++).