GLI1 and neoplasm: Moreover, this model system offers well characterized tumor-inducing molecular reagents (the human oncogenes Gli1, Xrel3, p53Trp248 and KRASG12D), whose expression results in induced tumor-like structures (ITLSs) with many of the hallmarks of mammalian tumors: increased mitotic activity, induced vasculogenesis, increased hypoxia, acidic microenvironment, disorganization of normal cell architecture, and ability to trigger an innate immune response [3, 4, 50, 67, 68].