For instance, HH/GLI represents a key molecular driver signal in basal cell carcinoma (BCC), medulloblastoma (MB) and rhabdomyosarcoma and has been implicated in the malignant progression of for instance gastrointestinal, pancreatic, ovarian, breast, prostate and lung cancers, melanoma, glioma, and several leukemia including chronic lymphocytic leukemia (CLL), chronic myeloid leukemia (CML), diffuse large B-cell lymphoma (DLBCL) and acute myeloid leukemia (AML) (for reviews see [2, 4, 12–22] and references therein). Here, GLI1 is linked to B-cell chronic lymphocytic leukemia.