KLF6 and glioblastoma: The KLF6 splice variant sv1 is aberrantly expressed in prostate, ovarian cancer and glioblastoma.16, 23 Upon splicing, KLF6-sv1 lacks a nuclear localization signal; therefore, it cannot transactivate KLF6 targets and supposedly is non-functional.24 Nevertheless, KLF6-sv1 has been shown to promote tumor progression and metastasis in various cancers.25, 26