GLI1 and central nervous system cancer: GLI1, along with its truncated homolog (TGLI1), which behaves as gain-of-function GLI1, were reportedly shown to mediate angiogenesis in gliomas by targeting the VEGF, MMP2, MMP9, VEGF-C, TEM7, and proangiogenic heparanase (HPSE) genes, respectively [23,24,25,26].