GLI1 and neoplasm: Shh activation, through mutations and/or abnormal transcriptional regulation and over-expression of downstream effector molecules such as the GLI family (GLI1, GLI2, GLI3) has been linked to the development of varied tumor types, from those affecting brain, skin, and muscle to cancers in other organs including the pancreas, prostate, lungs, and gastrointestinal tract [24].