GLI1 and medulloblastoma: Using real-time, RT-PCR we confirmed down-regulated expression of mRNA for downstream targets of Smoothened. Relative expression of Gli1, Gli2, N-myc, and cyclin-D1 was decreased 5.6, 7.6, 4.3, and 2.8-fold (p<0.05 for all transcripts), respectively in SmoA1 +; Pten +/− medulloblastomas (Figure 3B).